ГОДИШЕН ОТЧЕТ № 162010

ИНСТИТУТ ПО МИНЕРАЛОГИЯ И КРИСТАЛОГРАФИЯ „АКАД. ИВАН КОСТОВ“

БЪЛГАРСКА АКАДЕМИЯ НА НАУКИТЕ

Годишен отчет № 16, 2010Институт по минералогия и кристалография „Акад. Иван Костов“Българска академия на науките

Редакционна колегия:Д-р Желязко Дамянов – Главен редакторД-р Владислав Костов-КитинД-р Евгения ТарасоваД-р Людмил КонстантиновД-р Михаил ТарасовД-р Огнян ПетровЯна Цветанова

Адрес:София 1113, ул. „Акад. Г. Бончев“ бл. № 107Факс: (+359 2) 9797056Тел: (+359 2) 9797055E-mail: mincryst@interbgc.com

Web site: http://www.clmc.bas.bg

© Институт по минералогия и кристалография „Акад. Иван Костов“, 2010

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Съдържание

Въведение ........................................................................................................ 71. Предмет на дейност .................................................................................. 102. Структура и персонал ............................................................................... 143. Основно оборудване ................................................................................ 204. Научноизследователски теми ................................................................. 21

4.1. Минерални системи и минералогенезис ....................................... 211. Перцевит-(OH) – нов минерал в групата на перцевита,

Mg2(BO3)1–x(SiO4)x(F,OH)1–x(x<0.5), от находище Снежное, Република Саха-Якутия, Русия (И. О. Галускина, Л. Оттолини, М. Кадийски, Т. Армбрустер, Е. В. Галускин, П. Джержановски, А. Виниарски) .................................................... 21

2. Акцесорни шпинели в ултрамафични и мафични скали от Гегенския офиолитов меланж в Огражден планина, Югозападна България (П. Иванова, Н. Зидаров) .......................... 22

3. Първа находка на нефрит в тремолититово тяло от Огражден планина, Югозападна България (Н. Зидаров, Р. И. Костов, П. Зидаров) ...................................................................................... 24

4. Хидротермални флуоритообразуващи процеси в находище Михалково (Централни Родопи, България): природно наблюдение и експериментално потвърждение (Б. Зидарова) ................................................................................... 28

5. Превръщане на гранитоиди в ортошисти при метаморфизъм, благоприятстван от флуиди, Източни Родопи (Л. Мачева, В. Ганев) ....................................................................... 29

6. Петрология и геохронология на Витошката вулкано-плутонична постройка, Източно Средногорие, България (С. Атанасова-Владимирова, А. фон Куадт, П. Марчев, И. Пейчева, И. Пироева, Б. Маврудчиев) ................... 32

7. Съвременна електронна библиографска база данни за минералите от България (В. Костов-Китин, Р. И. Костов, П. Иванова) ...................................................................................... 33

8. Шлиховоминераложка карта на България – 2010 (О. Витов) ......................................................................................... 33

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4.2. Екологична и техногенна минералогия ......................................... 359. Минералогия, геохимия и екологосъобразно приложение

на твърди горива и продукти от тяхното изгаряне и пиролиза (С. Василев, Х. Василева, Д. Бакстер, Л. Андерсен, И. Костова, Дж. Хауер, М. Масталерц, Н. Николова, Д. Дахер) .................................................................... 35

10. Оползотворяване на рудите от находище Кремиковци – една минераложка гледна точка на базата на досегашните изследвания (Ж. Дамянов) ............................................................. 37

4.3. Биоминералогия ................................................................................4111. СЕМ изследване на морфологията и химичния състав

на нови фази, образувани при въздействие на Er:YAG лазер върху човешки зъби (Е. Тарасова, Г. Жегова, М. Тарасов, М. Рашкова) .................................................................................... 41

12. Биомиметични трансформации на аморфен калциев фосфат – изследване на кинетиката и термодинамиката (Д. Рабаджиева, Р. Гергулова, Р. Титоренкова, С. Тепавичарова, Е. Дюлгерова, Хр. Баларев, О. Петров) .......... 43

4.4. Археоминералогия ............................................................................4413. Археометрични изследвания на златни артефакти

от ранната бронзова епоха (РБЕ) от археологически обект „Дъбене” (З. Цинцов, М. Христов, С. Цанева, Б. Карацанова) ................................................................................. 44

4.5. Моделиране и модифициране на минерални системи ............... 4714. Получаване и структурно уточнение по метода на Ритвелд

на обменен на Ag+ клиноптилолит (Л. Димова, О. Петров, М. Кадийски, Н. Лихарева, А. Стоянова-Иванова, В. Микли) ....... 47

15. Кинетика и равновесие на Ag+-йонен обмен в Na-клиноптилолит (Н. Лихарева, Л. Димова, О. Петров, Я. Цветанова) ................................................................ 49

16. Бинарен катионен обмен в клиноптилолит с участие на K+, Na+, Ba2+ и Ca2+ при 30 и 95°C: калориметрично изследване (Н. Петрова, Л. Филизова, Г. Киров) ........................... 50

17. Трибохимична активация на природен и NH4+-обменен

клиноптилолит, смесен с природен апатит, с цел приложението му за опазване на околната среда (В. Петкова, Н. Петрова) ....... 52

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18. Енергийни аспекти на взаимодействието вулканична пепел–вода и зеолитизация на вулканично-пепелни скали (Г. Киров, Н. Петрова) ...................................................................... 54

4.6. Синтез, състав, структура и свойства на минерали и нови материали .............................................................................. 56

19. Растеж на смесени алкалоземни флуориди за приложение в лазерни матрици (Й. Т. Муховски) ............................................... 56

20. Количествен анализ на твърди разтвори в гранати от скарнови зони чрез използване на рентгенодифракционен метод на Ритвелд (Я. Цветанова, О. Петров) ............................... 57

21. Нови данни за кристалохимията на наноразмерни микропорести титаносиликати с фармакосидеритова структура (В. Костов-Китин, Р. Николова, Н. Накаяма, С. Симова, П. Цветкова, Р. Титоренкова, Н. Петрова, В. Ганев) ..................... 59

22. ATR IR-микроспектроскопия на частично неподреден циркон (Р. Титоренкова, Б. Гашарова, Б. Михайлова, Л. Константинов) .............................................................................. 61

23. TEM изследване на наноразмерен Al2(WO4)3 (Д. Нихтянова, Н. Величкова, Р. Петрова, И. Косева, А. Йорданова, В. Николов) .............................................................. 61

24. Изследване на пуцолановата активност и хидратационните продукти на циментови пасти с добавка на природни зеолити (В. Лилков, О. Петров, В. Петкова, Н. Петрова, Я. Цветанова) .................................................................................. 62

25. Реоложки, порозиметрични и СЕМ изследвания на цименти с добавки на природни зеолити (В. Лилков, О. Петров, Я. Цветанова)................................................................................... 63

26. Обновяване на Лабораторията по монокристален рентгеноструктурен анализ в ИМК-БАН (Р. Николова, О.Е. Петров, Б. Михайлова, Ю. Кълвачев, В. Костов, Б. Шивачев, М. Кадийски, М. Господинов, Т. Миленов, П. Рафаилов, Г. Авдеев, Т. Спасов, Г. Генчева, О.Л. Петров, В. Илиева, П. Гороломова, В. Куртева, К. Костова) .......................64

5. Монографии ................................................................................................ 676. Международно сътрудничество ............................................................. 707. Поканени учени .......................................................................................... 71

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Проекти и задачи № 12, 13, 21 и 26 са частично финансирани от Фонд „Научни изследвания“ към Министерството на образованието, младежта и науката.

8. Предлагани научноизследователски теми за международносътрудничество ......................................................................................... 71

9. Публикации и доклади .............................................................................. 729.1. Публикувани статии и доклади ....................................................... 729.2. Публикации, приети за печат ........................................................... 779.3. Доклади на научни форуми ............................................................. 789.4. Научно-популярни статии ................................................................ 81

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Въведение

Изминалата 2010 бе година на сериозна промяна в статута на инсти-тута, нови впечатляващи научни постижения, продължаващо обновление на изследователската инфраструктура и организация на важни международни и национални форуми в областта на нашата научна компетентност. Същевре-менно това бе година на безпрецедентна финансова рестрикция на бюджет-ната субсидия, която постави на силно изпитание способността ни за оцеля-ване, запазване на приемливо ниво на създадения изследователски ритъм и осигуряване на нормални условия за работа.

С решение на V-тото Общо събрание на БАН (Протокол № 26/22.03. 2010 г.) Централната лаборатория по минералогия и кристалография „Акад. Иван Костов“ (ЦЛМК) запази своя досегашен статут на самостоятелно по-стоянно научно звено на Академията и от 01.07.2010 г. бе преименувана в Институт по минералогия и кристалография „Акад. Иван Костов“ (ИМК) без изменения в структурата, състава и функциите си. Това бе резултат от високата оценка (А/А/А) за цялостната дейност на бившата ЦЛМК през пе-риода 2004–2008 г., определена като „международно конкурентоспособна научна организация с важни приноси в своята област“ от независимата Международна комисия за оценяване на постоянните научни звена на БАН от Европейската научна фондация и Европейската федерация на академи-ите на науките.

27 години след създаването на самостоятелно научно звено на БАН по проблемите на минералогията, кристалографията и минералните суровини, днес ИМК е сред водещите академични организации в страната. Институ-тът притежава доказан мултидисциплинарен научен капацитет, модерна из-следователска инфраструктура, способна да обезпечи конкурентоспособни изследвания в много широк спектър на природните науки, и добре разви-то проектно, институционално и кадрово сътрудничество с много наши и чуждестранни научни организации от най-различни области. Поради това в новата изследователска структура на Академията ИМК намери място като самостоятелно постоянно научно звено в направлението „Нанонауки, нови материали и технологии“.

Настоящият отчет обхваща дейността на института през 16-та година от създаването на ЦЛМК (1995 г.) и въвеждането на традицията за ежегодно пуб-ликуване в синтезиран вид на резултатите от изследователската ни работа.

Предмет на дейност, мисия и приоритети

Мисията на ИМК е да допринася за устойчивото развитие на общество-то и обогатяването на човешките познания в областта на минералогията и кристалографията чрез задълбочени мултидисциплинарни изследвания на природни, техногенни и експериментално моделирани минерални системи и синтезирани нови материали.

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Научноизследователската работа в института е подчинена изцяло на неговия предмет на дейност: „Фундаментални и приложни изследвания, консултантска, експертна, обслужваща и аналитична дейност, приложение на научните резултати и подготовка на висококвалифицирани специалисти в областта на минералогията и кристалографията, изследване и моделира-не на природни и техногенни минерални системи“.

На базата на предмета на дейност в ИМК са формирани 5 приоритет-ни научни направления, които определят неговия облик и сфери на научна компетентност, както следва:

ИЗУЧАВАНЕ НА ЗЕМЯТА– Изследване на минерали и минерални системи с цел определяне на

техния състав, структура, свойства, взаимоотношения, процеси на форми-ране и изменение и закономерности в разпределението.

– Разработване на генетични модели и критерии за прогнозиране, тър- Разработване на генетични модели и критерии за прогнозиране, тър-сене и проучване на находища на минерални суровини.

НОВИ МАТЕРИАЛИ И ТЕХНОЛОГИИ– Израстване, синтез и характеризиране на моно- и поликристални ма- Израстване, синтез и характеризиране на моно- и поликристални ма-

териали (оптични кристали, микро- и мезопорести фази, стъкла и др.).– Модифициране на минерали и материали с цел подобряване на тех- Модифициране на минерали и материали с цел подобряване на тех-

ните сорбционни, каталитични и йонообменни свойства и търсене на въз-можности за оптимално приложение.

ОПАЗВАНЕ НА ОКОЛНАТА СРЕДА– Изучаване на важни за опазването и екологосъобразното ползване

на околната среда природни и техногенни минерални системи с акцент вър-ху въглища, руди и отпадъчни продукти от преработката им.

ПРИРОДА И СУРОВИННИ РЕСУРСИ НА БЪЛГАРИЯ– Изследване, научен анализ и прогнозиране на минералносуровинни- Изследване, научен анализ и прогнозиране на минералносуровинни-

те ресурси на България с цел ефективното и екологосъобразното им опол-зотворяване.

– Изучаване, опазване и съхраняване на минералното разнообразие на страната.

ПОДГОТОВКА НА ВИСОКОКВАЛИФИЦИРАНИ СПЕЦИАЛИСТИ– Програмна акредитация за обучение по образователната и научна

степен „доктор“ за научната специалност „Минералогия и кристалография“.– Учебни програми и специализирани курсове за студенти и специали- Учебни програми и специализирани курсове за студенти и специали-

сти от наши и чуждестранни университети и научни институти.

Връзка с политиките и програмите на БАН за периода 2009–2013 г.Характерът на изучаваните обекти и мултидисциплинарният подход в

научното търсене в ИМК изцяло се вписват в главната стратегическа цел на БАН – „Българската академия на науките – двигател в изграждането на общество, базирано на знание и активен партньор в европейското изследо-вателско пространство“.

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ИМК участва в реализацията на следните политики и програми на БАН:Политика 1: Науката – основна двигателна сила за развитие на на-ционалната икономика и общество, базирани на знания.Програма 1.2: „Устойчиво развитие, рационално и ефективно из-

ползване на природните ресурси“ посредством: изследване, научен ана-лиз и прогнозиране на минералносуровинните ресурси на България с цел ефективно оползотворяване и природосъобразно и устойчиво развитие на националната инфраструктура и икономика; изучаване, поддържане и опаз-ване на минералното разнообразие, геоложкото и ландшафтното природно наследство на страната.

Програма 1.3: „Конкурентоспособност на българската икономика и на научния иновационен капацитет“ – чрез научна подкрепа на най-съвре-– чрез научна подкрепа на най-съвре- чрез научна подкрепа на най-съвре-менно равнище на българския бизнес за реализирането на успешни инова-тивни проекти и създаване на нови конкурентни научни продукти и техноло-гии за нуждите на индустрията.

Програма 1.5: „Информационно, експертно и оперативно обслужване на българската държава и общество“ – чрез извършване на оперативни екс-– чрез извършване на оперативни екс- чрез извършване на оперативни екс-пертни оценки, анализи и препоръки по най-актуални проблеми, свързани със състава, структурата и свойствата на материята (природна или техногенна).

Програма 1.6: „Качествено и конкурентоспособно обучение“ посред-ством създаването на оптимални условия за научно израстване и пълно-ценна реализация на учените от ИМК и обучаваните от наши сътрудници студенти, докторанти и специалисти в условията на силно конкурентното европейско научноизследователско пространство.

Политика 2: Научен потенциал и изследователска инфраструктура – част от Европейското изследователско пространство.Международната дейност на ИМК понастоящем се осъществява чрез

двустранни институционални договори по линия на академичния обмен, по конкурсните програми на Фонд „Научни изследвания“ (ФНИ) и на европей-„Научни изследвания“ (ФНИ) и на европей-Научни изследвания“ (ФНИ) и на европей-“ (ФНИ) и на европей- (ФНИ) и на европей-ски институции, както и чрез гостуване на наши учени в чужди университети и изследователски центрове въз основа на спечелени конкурси, специали-зации, по съвместни проекти или по покана. През последните 3 години в института тече активна подмяна на остарялото научно оборудване с нова модерна техника, като база за провеждане на международно конкуренто-способни научни изследвания в областта на изучаването на минерали, ми-нерални системи и нови материали, разработването на генетични модели за търсене и проучване на находища на минерални суровини, създаването и модифицирането на материали и минерали с цел подобряването на техните полезни свойства

Политика 3: Националната идентичност и културното разнообра-зие в Европа и света.Програма 3.2: „Историята на българските земи, България и бълга-

рите“ – посредством участието в издирването и изучаването на археологи-

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чески и архитектурни паметници и артефакти от древността до наши дни и развитието на нови научни направления като археоминералогията и геоар-хеологията.

Научен капацитет и тематичен обхватИМК е мултидисциплинарно научно звено на БАН с екип от висококва-

лифицирани специалисти в областта на минералогията, кристалографията, минералните суровини, физиката и химията, работещи в естествено създа-дени, водещи в страната и добре познати в чужбина научноизследователски групи по:

– Минералогия, геохимия и оползотворяване на въглища и въглищни продукти

– Моделиране, картиране и прогнозиране на минерални находища– Структурни и химични трансформации на минерали и материали– Технологична минералогия– Археоминералогия– Минералогия и картиране на шлихи– Кристална структура, състав и свойства на минерали и материали– Природни зеолити и микропорести аналози– Синтез на нови функционални и наноразмерни материали– Кристален растеж на оптически кристалиРазработваните в ИМК основни научни и научно-приложни тематики

са с международно доказана продуктивност и конкурентоспособност. През последните години се извършва балансирано тематично адаптиране към националните и европейските научни приоритети с акцент върху ефектив-ното използване на минерални суровини и отпадъци, материалознание и нанотехнологии, екология и културно-историческо наследство.

72% от научния състав на ИМК е хабилитиран, 92% е с докторски сте-пени, а по-голямата част от учените са специализирали във водещи светов-ни научни центрове.

Изследователска инфраструктураСъс своите 8 собствени лаборатории и дялово участие в други 3 външ-

ни, в момента ИМК е най-добре оборудваната и с най-висококвалифициран научен състав и обслужващ персонал организация в България в областта на детайлното изследване на структурата, състава, свойствата, поведени-ето и взаимодействията на твърдата материя (независимо от произхода и размерите ѝ) и системите, които тя формира.

През последните години по наша инициатива бяха организирани кон-сорциуми от водещи научни институти на БАН, СУ, ХТМУ и ИМК (като ба-зова организация) за закупуване чрез конкурсно и бюджетно финансира-не на изследователска апаратура от най-ново поколение: нов сканиращ електронен микроскоп SEM EVO 25LS – CARL Zeiss SMT, нова комплексна

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термохимична апаратура SETSYS Evolution 24 TGA-DTA/DSC с масспектро-метър Omnistar за анализ на газовата фаза на Setaram Instrumentation, ин-фрачервен микроскоп Hyperion 2000 на Bruker, нов прахов дифрактометър Bruker AXS – D2 Phaser, нов монокристален дифрактометър Oxford Diffraction Supernova A с температурна приставка Oxford Cryosystems Cobra и др.

Понастоящем ИМК разполага с изключително мощна апаратурна база, способна на практика да покрие почти целия научноизследователски диапа-зон в сферата на материалознанието.

Общонационални и оперативни дейности, обслужващи държаватаИМК участва в организацията и управлението на редица дейности с

национален характер:– ИМК е научно средище на българската минераложка общност, обеди- ИМК е научно средище на българската минераложка общност, обеди-

нена в Българското минералогическо дружество. В института се провеждат регулярните сбирки на дружеството, където наши и чужди учени докладват и дискутират актуални резултати от научни изследвания в областта на ми-нералогията и минералните ресурси.

– ИМК е седалище на Българското кристалографско дружество с Председател доц. д-р О. Петров – ръководител на секция „Експеримен-тална минералогия и кристалография“ и Лабораторията по рентгенострук-турен анализ в института. Под егидата на Управителния съвет на друже-ството на 21–23.10.2010 г. беше проведен II Национален кристалографски симпозиум.

– ИМК чрез свои учени е активен участник в организационната и изда- ИМК чрез свои учени е активен участник в организационната и изда-телската дейности на Българското геологическо дружество.

– ИМК е: хранител на базовата академична колекция „Минералното разнообразие на България“, в която се съхраняват уникални образци от ми-“, в която се съхраняват уникални образци от ми-, в която се съхраняват уникални образци от ми-нералното богатство на страната и специализирани работни материали от изследователските проекти и задачи на учените-минералози от института; активен участник в националните и международните форуми на издигнатата от Националния музей „Земята и хората“ Софийска инициатива „Съхраня-“ Софийска инициатива „Съхраня- Софийска инициатива „Съхраня-ване на минералното разнообразие“, чиято основна цел е да опази за бъде-“, чиято основна цел е да опази за бъде-, чиято основна цел е да опази за бъде-щите поколения минералното богатство на Земята.

Потребители на научни продукти и аналитични изследвания на ИМК през 2010 г. са редица водещи у нас индустриални предприятия (БАЛКАН-ФАРМА–Дупница АД, КЦМ АД – Пловдив, Каолин АД, Геомак ЕООД, Пор-ше Интер Ауто БГ ЕООД, Пътконсулт ООД, Агрия АД, Девня Цимент АД, Сензор-Найт Индастриъл ЕООД, Целзиан ООД), научни институти от БАН (Национален археологически институт с музей, Институт по металознание, Институт по микробиология, Институт по органична химия с център по фито-химия), университети (Софийски Университет „Св. Климент Охридски“, Мин-но-геоложки университет „Св. Иван Рилски“, Химикотехнологичен и металур-гичен университет, Медицински университет – София, Бургаски университет

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„А. Златаров“, Университета на Лиеж, Белгия), музеи (Национален истори-чески музей, Общински исторически музей, гр. Средец) и др.

Резултати от научната дейност през 2010 г.В съответствие със своята мисия, предмет на дейност и приоритети на-

учноизследователската дейност на ИМК през 2010 г. е отразена в разработ-ваните научни и научно-приложни проекти и задачи (Раздел 4), получените през отчетната година научни резултати, публикувани или приети за печат в престижни международни и наши периодични издания или представени на международни и наши научни форуми (Раздел 9), както и от участието в различни форми на международно сътрудничество (Раздел 6).

През годината е работено по 7 проекта, финансирани от бюджета на БАН, 12 - финансирани по договори с ФНИ, 1 – от европейската Изпълнителна агенция за здравеопазване и защита на потребителите (EAHC), 1 – от Фонда-(EAHC), 1 – от Фонда-EAHC), 1 – от Фонда-), 1 – от Фонда- 1 – от Фонда-– от Фонда- от Фонда-ция „Александър фон Хумболт“, и 3 – по линия на двустранното международ-“, и 3 – по линия на двустранното международ-, и 3 – по линия на двустранното международ-но сътрудничество (с Чешката, Естонската и Руската академии на науките). Научните резултати на учените от ИМК за 2010 г. са отразени в общо 101 пуб-ликации – количество сравнимо с данните за последните 3 години. 70 от тези публикации са в международни списания и сборници, а 31 – у нас. Излез-лите от печат са общо 80, а приетите – 21. Публика циите в международни списания са 29 – брой, сравним със средногодишния за одитирания 5-го-9 – брой, сравним със средногодишния за одитирания 5-го- – брой, сравним със средногодишния за одитирания 5-го-– брой, сравним със средногодишния за одитирания 5-го- брой, сравним със средногодишния за одитирания 5-го-дишен период 2005–2008 (около 30 бр./год.). В същото време бележат известен спад тези в български списания – 14 (20 – 2009 г., 16 – 2008 г. и 15 – 2007 г.). През 2010 г. у нас излезе от печат монографията „Ахатите в България“ (София, Изд. „Ваньо Недков“, 210 с.) с автори З. Цинцов (ИМК) и Б. Банушев (МГУ) – един обобщителен труд, плод на дългогодишно сис-темно и задълбочено изучаване на над 70 ахатови проявления в страната. Нашият учен Й. Муховски е автор на “Chapter 1. Growth of Single and Mixed Alkali Earth Fluoride Crystals with Wide Application. Control of Crystallization Zone Contamination and Stability of Melt-Crystal Interface” от монографията “Fluoride: Properties, Applications and Environmental Management” (Ed. B. Mullin) на издателството Nova Science Publishers, Inc.

Най-важните научни и научно-приложни резултати от дейността през 2010 г. включват постижения в следните приоритетни за ИМК направления:

Природни и техногенни минерални системиНа базата на детайлен анализ на данните за химичния състав на 86

вида биомаса (дървесина, треви, слама, водорасли, аграрни отпадъци с растителен и животински произход, замърсена отпадъчна биомаса и др.) е разработена система за класифициране на природните и техногенните групи биомаса според химичния им състав*. Предложената класификация е удобно, надеждно и ефективно средство за базова оценка на биомасата като алтернативно гориво за производството на енергия при съвместно изгаряне

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с въглища, на биогорива и на химични продукти в биорафинериите. Изслед-ването представлява важен принос за устойчивото и ефективно използване на биомасата като суровина, както и за екологично безопасната употреба на отпадните продукти от нейната преработка (Съвместно изследване на ко-лектив с ръководител проф. дгн Ст. Василев от ИМК – БАН и учени от Ин-ститута по енергетика на Съвместния изследователски център на Евро-пейската комисия (JRC-IE) [* Vassilev, S., D. Baxter, L. Andersen, C. Vassileva. 2010. An overview of the chemical composition of biomass. Fuel, 89 (5): 913-933. Статията е спечелила наградата „Best peer reviewed article“ на JRC-IE за 2010 г. След публикуването си, тя заема трето място в класацията за най-че-тени статии на сп. FUEL за периода януари-юни 2010 г., 4 място за периода октомври 2009 – септември 2010 г., а за периода юли-септември 2010 г. е на 15-то място в класацията за най-четени статии на всички (52) списания в областта на енергетиката, включени в ScienceDirect (ScienceDirect Top 25)].

Синтез, модифициране и структурно охарактеризиранеНа базата на проведените експерименти със самоуплътняващи се

циментови състави с активна минерална добавка от природни зеолити и извършените върху тях хидратационни, реоложки, порометрични, термогра-виметрични и калориметрични изследвания е доказана перспективността за използване на зеолити от български и световни находища в циментовата промишленост*. (Колектив с ръководител доц. д-р О. Петров съвмест-но с учени от катедра „Физика“ на Минно-геоложкия университет „Св. Иван Рилски“) [* Материали от “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010].

АрхеоминералогияПрез 2010 г. за първи път в световната практика е проведено системно

изследване на представителна извадка от 495 бр. златни артефакти от един обект от ранната бронзова епоха (трето хилядолетие пр. Хр., археологиче-ски обект „Дъбене“)*; изяснен е химичният състав на артефактите, пред-ставляващи сплави от бинарната система Au-Ag със силно доминираща роля на Au; за първи път е доказано използването на памук по нашите земи през ранната бронзова епоха чрез откриването на снопчета влакна в един от златните разпределители. (Колектив с ръководител доц. д-р З. Цинцов съвместно с учени от Националния исторически музей) [* Проект „Архео-метрични изследвания на златни артефакти от ранна бронзова епоха (РБЕ) – археологически обект „Дъбене“].

София, януари 2010 г. Ж. Дамянов

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ANNUAL REPORT # 162010

INSTITUTE OF MINERALOGY AND CRYSTALLOGRAPHY “ACAD. IVAN KOSTOV”

BULGARIAN ACADEMY OF SCIENCES

Annual Report # 16, 2010Institute of Mineralogy and Crystallography “Acad. Ivan Kostov”, Bulgarian Academy of Sciences

Editorial Board:Dr. Zhelyazko Damyanov – EditorDr. Eugenia TarassovaDr. Ludmil KonstantinovDr. Mihail TarassovDr. Ognyan PetrovDr. Vladislav Kostov-KytinM.Sc. Yana Tzvetanova

Address:Acad. G. Bonchev Str., bl. 107, 1113 Sofia, BulgariaFax: (+359 2) 9797056 Phone: (+359 2) 9797055E-mail: mincryst@interbgc.com

Web site: http://www.clmc.bas.bg

© Institute of Mineralogy and Crystallography “Acad. Ivan Kostov”, 2010

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Contents

Introduction ........................................................................................................ 71. Trends of activity ......................................................................................... 102. Structure and Staff ...................................................................................... 143. Main Equipment ........................................................................................... 204. Research Topics .......................................................................................... 21

4.1. Mineral systems and mineral genesis ............................................... 211. Pertsevite-(OH), a new mineral in the pertsevite series,

Mg2(BO3)1–x(SiO4)x F,OH)1–x(x < 0.5), from the Snezhnoye deposit in Sakha-Yakutia Republic, Russia (I.O. Galuskina, L. Ottolini, M. Kadiyski, Th. Armbruster, E. V. Galuskin, P. Dzierżanowski, A. Winiarski) ...................................................................................... 21

2. Spinel accessories in ultramafic and mafic rocks from Gega ophiolite melange in Ograzhden Mountain, SW Bulgaria (P. Ivanova, N. Zidarov) ..................................................................... 22

3. First find of nephrite in tremolitite body from Ograzhden Mountain, SW Bulgaria (N. Zidarov, R. I. Kostov, P. Zidarov) ......................................................................................... 24

4. Hydrothermal fluorite-forming processes in the Mikhalkovo deposit (Central Rhodopes, Bulgaria) – Field observation and experimental confirmation (B. Zidarova) .................................... 28

5. Fluid enhanced metamorphic transformations of granitоid rocks into orthoschists, East Rhodopes (L. Macheva, V. Ganev)..................................................................... 29

6. Petrology and geochronology of the Vitosha volcano-plutonic edifice, Western Srednogorie, Bulgaria (S. Atanasova-Vladimirova, A. von Quadt, P. Marchev, I. Peytcheva, I. Piroeva, B. Mavroudchiev) ....................................... 32

7. State-of-the-art electronic bibliographic data base on minerals from Bulgaria (V. Kostov-Kytin, R. I. Kostov, P. Ivanova) .................................................................... 33

8. Map of stream-sediment minerals of Bulgaria – 2010 (O. Vitov) ........................................................................................... 33

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4.2. Environmental and technogenic mineralogy .................................... 359. Mineralogy, geochemistry and environmentally safety application

of solid fuels and their combustion and pyrolysis products (S. Vassilev, C. Vassileva, D. Baxter, L. Andersen, I. Kostova, J. Hower, M. Mastalerz, N. Nikolova, D. Daher) ................................ 35

10. Utilization of the Kremikovtsi ores: A mineralogical viewpoint based on the available data (Z. Damyanov) ..................................... 37

4.3. Biomineralogy .....................................................................................4111. SEM investigation of morphology and chemical composition

of neo-phases formed during Er:YAG laser irradiation of human teeth (E. Tarassova, G. Zhegova, M. Tarassov, M. Rashkova) ......... 41

12. Biomimetic transformations of amorphous calcium phosphate – kinetic and thermodynamic studies (D. Rabadjieva, R. Gergulova, R. Titoren kova, S. Tepavitcharova, E. Dyulgerova, Chr. Balarew, O. Petrov) ............ 43

4.4. Archaeomineralogy .............................................................................4413. Archeometrical studies of gold artifacts from the

Early Bronze Age (EBA) from Dubene Archaeological Site (Z. Tsintsov, M. Hristov, S. Tsaneva, V. Karatsanova) ...................... 44

4.5. Modelling and modification of mineral systems .............................. 4714. Preparation and Rietveld refinement of Ag-exchanged

clinoptilolite (L. Dimova, O. Petrov, M. Kadiyski, N. Lihareva, A. Stoyanova-Ivanova, V. Mikli)......................................................... 47

15. Kinetics and equilibrium of ion exchange of Ag+ on Na-clinoptilolite (N. Lihareva, L. Dimova, O. Petrov, Y. Tzvetanova)................................................................................... 49

16. Binary cation exchange in clinoptilolite, involving K+, Na+, Ba2+ and Ca2+: A calorimetric study at 30 and 95°C (N. Petrova, L. Filizova, G. Kirov) ...................................................... 50

17. Tribochemical activation of natural or NH4+-exchanged

clinoptilolite mixed with natural apatite for environmental applications (V. Petkova, N. Petrova) ................................................ 52

18. Energetic aspects of volcanic ash-water interaction and zeolitization of volcanic ash rocks (G. Kirov, N. Petrova) ........................................................................ 54

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4.6. Synthesis, composition, structure, and properties of mineralsand new materials ............................................................................... 56

19. Growth of mixed alkaline-earth fluorides for laser host applications (J. Mouchovski) ..................................................... 56

20. Quantitative analysis of garnet solid solutions from skarn zones using Rietveld-based XRD method (Y. Tzvetanova, O. Petrov) ................................................................ 57

21. New data on the crystal chemistry of nano-sized microporous titanosilicates with pharmacosiderite structure (V. Kostov-Kytin, R. Nikolova, N. Nakayama, S. Simova, P. Tzvetkova, R. Titorenkova, N. Petrova, V. Ganev) ........................ 59

22. Attenuated total-reflection infrared microspectroscopy of partially disordered zircon (R. Titorenkova, B. Gasharova, B. Mihailova, L. Konstantinov) ........................................................... 61

23. TEM study of nanosized Al2(WO4)3 (D. Nihtianova, N. Velichkova, R. Petrova, I. Koseva, A. Yordanova, V. Nikolov) ......................................................................................... 61

24. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites (V. Lilkov, O. Petrov, V. Petkova, N. Petrova, Y. Tzvetanova) .......... 62

25. Rheological, porosimetric, and SEM studies of cements with additions of natural zeolites (V. Lilkov, O. Petrov, Y. Tzvetanova)................................................................................... 63

26. New equipment in the laboratory “X-ray diffraction structural analysis” – IMC-BAS (R. Nikolova, O. Petrov, B. Mihailova, Y. Kalvachev, V. Kostov, B. Shivachev, M. Kadiyski, M. Gospodinov, T. Milenov, P. Rafailov, G. Avdeev, T. Spassov, G. Gencheva, O. Petrov, V. Ilieva, P. Gorolomova, V. Kurteva, K. Kostova) .........................................................................64

5. Monographs ................................................................................................. 676. International Cooperation ........................................................................... 707. Visiting Scientists ........................................................................................ 718. Research Topics, Announced for International Partnership

Collaboration ............................................................................................... 719. Publications and Reports at Scientific Forums ........................................ 72

9.1. Published Articles and Reports ......................................................... 72

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9.2. Publications in press .......................................................................... 779.3. Reports at Scientific Forums ............................................................. 789.4. Popular scientific papers .................................................................... 81

Projects and topics # 12, 13, 21 and 26 are financially supported in part by the Bulgarian National Science Fund of the Ministry of Education, Youth and Science.

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Introduction

Past 2010 was a year of major change in the status of the Institute, impres-sive new scientific achievements, continuing equipment renovation and organi-zation of important international and national forums in the field of our scientific competence. At the same time, it was a year of unprecedented financial squeeze on the budget subsidy that put to a strong test our ability to survive, maintain an acceptable level of the created research rhythm and ensuring decent working conditions.

Based on the Decision of the 26th Meeting (#26/22.03.2010) of the 5th Gen-eral Assembly of the Bulgarian Academy of Sciences (BAS), from July 1, 2010, the Central Laboratory of Mineralogy and Crystallography (CLMC) was renamed to Institute of Mineralogy and Crystallography “Acad. Ivan Kostov” (IMC) without changes in the structure, staff and functions. This was the result of the high overall score (A/A/A) for the five-year (2004-2008) achievements and ac-tivities of CLMC which was evaluated as “an internationally competitive research unit with demonstrated important contributions to the field” from the independent International Science Review Committee from the European Science Foundation (ESF) and the European Federation of National Academies of Sciences and Hu-manities (ALLEA: All European Academies).

27 years after the founding of an independent research unit of the BAS on the problems of mineralogy, crystallography and mineral resources, today IMC is among the leading academic organizations in the country. The Institute has dem-onstrated a multidisciplinary scientific capacity, modern research infrastructure able to provide competitive research in a very wide range of natural sciences, and well-developed project, institutional and personnel cooperation with many domestic and foreign scientific organizations from various fields. For that reason, the Institute was included in the Research Field “Nanosciences, New Materials and Technologies” in the new organizational structure of the BAS.

This annual report presents the activities of the Institute during the sixteenth year of founding of the former CLMC and starting the tradition of annual publish-ing of our summarized research results.

Scientific activities during 2010In accordance with its mission, areas of activities and priorities, the research

activity of IMC in 2010 is reflected in the developed research topics (Section 4), the results of which have been published or accepted for publication in high-quali-ty peer-reviewed international and national journals or in proceedings of scientific

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forums (Section 9) as well as by the participation in different forms of international cooperation (Section 6).

During 2010 the activity of IMC was concentrated in 7 projects financed by the BAS budget, 12 co-financed by contracts with the Bulgarian National Science Fund (NSF), 1 co-financed by the European Executive Agency for Health and Consumers (EAHC), 1 by the Alexander von Humboldt Foundation, and 3 by the bi-lateral cooperation with the Academies of Sciences of Czech Republic, Estonia and Russia.

The scientific results of IMC during the year are presented in 101 publica-tions, a number comparable with that for the last years. 70 of these publications are in international and foreign journals and issues and 31 in Bulgaria. 80 of these are already available, while 21 are in press. The publications in international jour-nals are 29, a number comparable with that per year averaged over the evaluated five-year period (near 30 per year). The number of publications in Bulgarian jour-nals (14) marks some decrease while those in international or foreign proceed-ings (41) has increased substantially.

In 2010 was published the monograph “Agates in Bulgaria” (in Bulgarian, 210 pp.) by Zdravko Tsintsov (from IMC) and Banush Banushev (UMG), a sum-mary work that is the result of long-term systematic and extensive research of more than 70 agate deposits and occurrences in Bulgaria. J. Mouhovski from IMC published “Chapter 1. Growth of Single and Mixed Alkali Earth Fluoride Crystals with Wide Application. Control of Crystallization Zone Contamination and Stability of Melt-Crystal Interface” from the monograph “Fluoride: Properties, Applications and Environmental Management” (Ed. B. Mullin), Nova Science Publishers, Inc.

The most important scientific and applied results obtained during 2010 in-clude achievements in the following priority scopes of IMC:

NATURAL AND TECHNOGENIC MINERAL SYSTEMS

A classification system of the natural and technogenic groups of biomass ac-cording to their chemical composition has been developed based on the extend-ed review of data for the chemical composition of 86 biomass varieties (woody, grass, straw, shells, pits, agricultural and animal biomass, algae, refuse and con-taminated biomass, etc.)*. The proposed classification is convenient, reliable and effective tool for basic assessment of biomass as alternative fuel for energy pro-duction in co-firing with coal, for biofuels and chemical products in biorefineries. The study represents an important contribution to the sustainable and efficient

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use of biomass as raw material as well as to the ecologically friendly utilization of waste products from its processing. (Research Group of Prof. S. Vassilev in collaboration with the Institute for Energy - Joint Research Centre (JRC-IE) at Eu-ropean Commission) [* Vassilev, S., D. Baxter, L. Andersen, C. Vassileva. 2010. An overview of the chemical composition of biomass. Fuel, 89 (5): 913-933. The paper has been awarded „Best peer reviewed article” of JRC-IE in 2010. After its publication, it ranks 3rd in the list of most read articles of FUEL for the period January-June 2010, 4th for the period October 2009-September 2010, and for the period July-September 2010 is 15th in the list of most read articles of all (52) journals in the field of energy included in ScienceDirect (ScienceDirect Top 25)].

SYNTHESIS, MODIFICATION AND STRUCTURAL CHARACTERIZATION

Based on experiments with self-packing cement pastes with active mineral addition of natural zeolites and hydration, rheological, porosimetric, thermogravi-metric and calorimetric studies carried out on them, it was demonstrated the perspective of using zeolites from Bulgarian and foreign deposits in the cement industry*. (Research Group of Assoc. Prof. O. Petrov in collaboration with De-partment of Physics, University of Mining and Geology “St. Ivan Rilski”) [* Papers from “Zeolite 2010” – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010].

ARCHAEOMINERALOGY

In 2010, for the first time in the world practice, a systematic investigation was carried out on a representative extract of 495 gold artifacts from one archaeologi-cal site from the Early Bronze Age (3rd millennium BC, Dubene Archaeological Site)*. The chemical composition of artifacts was established. The artifacts are composed of alloys from the Au-Ag binary system with the highly dominant role of Au. The use of cotton during the Early Bronze Age was established for the first time in our lands by finding of remains of textile fibers in one of the artifacts – gold separator. (Research Group of Assoc. Prof. Z. Tsintsov in collaboration with the National Museum of History) [* Project “Archeometrical studies of gold artifacts from the Early Bronze Age (EBA) from Dubene Archaeological Site”].

Sofia, January 2010 Z. Damyanov

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1. Trends of activity

Short history

Acad. Ivan Kostov Institute of Mineralogy and Crystallography (the former Central Laboratory of Mineralogy and Crystallography – CLMC) of the Bulgarian Academy of Sciences is a leading scientific institution in Bulgaria in the field of mineralogy and crystallography. It conducts comprehensive interdisciplinary re-search of natural, technogenic and experimentally modeled mineral systems and synthesized new materials.

The CLMC was established on the 1st of March, 1995. It inherited the best specialists, the equipment and the most vital scientific themes from the former ac-ademic Institute of Applied Mineralogy (1984). Since 2005 the CLMC was named after the famous Bulgarian mineralogist and crystallographer Academician Ivan Kostov. The CLMC was renamed to Institute of Mineralogy and Crystallography “Acad. Ivan Kostov” from July 1, 2010.

Mission, areas of activities and priorities

The IMC mission is to contribute to the sustainable development of society and enlarging human knowledge in the fields of Mineralogy and Crystallography by comprehensive multidisciplinary research of natural, technogenic and experi-mentally modeled mineral systems and synthesized new materials.

The main areas of activities of IMC include basic studies and applied re-search, consulting, expertise, service and analytic activities, practical application of scientific results and training of high qualified specialists in the fields of miner-alogy and crystallography, investigation and modeling of natural and technogenic mineral systems.

Based on the outlined areas of activities, the main scientific priorities of IMC are:

UNDERSTANDING THE EARTH

– Investigation of minerals and mineral systems aiming at determination of their composition, structure, properties, relationships, processes of formation and alteration, and modes of distribution.

– Development of genetic models and criteria for prognosis, prospecting and exploration of mineral deposits.

NEW MATERIALS AND TECHNOLOGIES

– Growing, synthesis and characterization of single and polycrystalline ma-terials (optical and laser-grade single crystals, micro- and mesoporous phases, glasses, etc.).

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– Modification of minerals and materials aiming at improving their sorption, catalytic and ion-exchange properties as well as searching for possibilities for their optimal application.

ENVIRONMENTAL PROTECTION

– Investigation of important for environmental protection and ecologically friendly utilization natural and technogenic mineral systems accentuating at coals, ores, and waste products of their processing.

NATURE AND NATURAL RESOURCES OF BULGARIA

– Investigation, analysis, and prognosis of mineral resources of Bulgaria aiming at their effective and environmentally friendly utilization.

– Studying, preservation and collecting of the mineral diversity, geological and landscape natural heritage of Bulgaria through supporting “National Minera-logical Database”, “Heavy Minerals Map of Bulgaria”, and a basic academic col-lection “Mineral Diversity of Bulgaria”.

TRAINING AND EDUCATION

– National Program Accreditation for education and training of PhD students in “Mineralogy and Crystallography”.

– Educational programs and training courses for students and specialists from Bulgarian and foreign universities and institutes.

Relation with the research policies and programs of BAS

The topics developed and the multidisciplinary research approach in the IMC fit entirely the main strategic goal of BAS in the period 2009–2013: “The Bul-garian Academy of Sciences must be the driving force in building a knowledge-based society and an active partner in the European Research Area.”

Within the framework of the BAS strategic policies “Science as the main driving force in the development of knowledge-based national society and econ-omy”, “Scientific potential and research infrastructure as a part of the European Research Area” and “ National identity and cultural diversity in Europe and in the world”, the IMC participates in the realization of the following basic programs:

– Sustainable development, rational and efficient use of natural resources– Competitiveness of the Bulgarian economy and capacity for scientific in-

novation– Informational, expert and operative services to the Bulgarian state and

society– High-quality competitive education– The history of Bulgaria, Bulgarian lands and Bulgarian people

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Research topics and capacity

IMC is a multidisciplinary research unit of BAS with a team of high-qualified specialists in the fields of mineralogy, crystallography, mineral resources, physics and chemistry working in leading in Bulgaria and well-recognized abroad Re-search Groups in:

– Mineralogy, Geochemistry and Utilization of Coal and Coal Products– Mineral Deposits Modeling, Mapping and Prognosis– Structural and Chemical Transformations of Minerals and Materials– Technological Mineralogy– Archaeomineralogy– Mineralogy and Mapping of Heavy Minerals Concentrates– Crystal Structure, Composition and Properties of Minerals and Materials– Natural Zeolites and Microporous Analogs– Synthesis of New Functional and Nanosized Materials– Crystal Growth of Optical CrystalsThe productivity and competitiveness of the main research topics, devel-

oped in IMC, are internationally proven. During the last years they are gradually adapted to the national and European scientific priorities with emphasis on the efficient utilization of mineral resources, raw materials and wastes, materials sci-ence and nanotechnology, ecology and cultural and historical heritage.

About 72% of the IMC research staff is habilitated, more than 92% is with academic degrees (DSc and PhD), and the majority of scientists have specialized in world’s leading scientific institutions.

Research infrastructure

With its own 8 analytical and service laboratories and shares in other 3 external ones, IMC is currently the best equipped and with most highly qualified research staff organization in Bulgaria in the field of detail study of structure, composition, properties, behavior and interactions of solid matter (regardless of its origin and size) and systems it forms.

During the last few years, IMC, as a principal institution, organized con-sortia with leading BAS institutes, Sofia University and University of Chemical Technology and Metallurgy for purchasing modern research infrastructure by budget and project financing: new scanning electron microscope SEM EVO 25LS – CARL Zeiss SMT, new thermochemical equipment SETSYS Evolution 24 TGA-DTA/DSC with mass spectrometer OmniStar of Setaram Instrumenta-tion, new infrared microscope Hyperion 2000 of Bruker, new X-ray powder dif-

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fractometer D2 Phaser Bruker AXS, new X-ray single crystal diffractometer Ox-ford Diffraction Supernova A with two X-ray sources and Oxford Cryosystems Cobra temperature attachment, etc.

Currently IMC has a powerful set of analytical equipment which is capable of ensuring practically the whole research range in the field of materials science.

Activities of national importance

IMC is engaged in the organization and management of a range of activi-ties of particular national importance for the science and society:

– IMC is a scientific centre of the Bulgarian mineralogical community united in the Bulgarian Mineralogical Society. The regular monthly sessions of the Min-eralogical Society are held in IMC where Bulgarian and foreign scientists report and discuss new results from their research in the fields of mineralogy and min-eral resources.

– IMC is the seat of the Bulgarian Crystallographic Society with Chairman Assoc. Prof. Dr. O. Petrov – Head of Department “Experimental Mineralogy and Crystallography” and the Laboratory of X-Ray Diffraction Analysis.

– IMC is a vigorous member in the organizing and publishing activities of the Bulgarian Geological Society.

– IMC is a custodian of the basic academic collection “Mineral Diversity of Bulgaria” including unique samples of the Bulgarian mineral wealth as well as specialized working materials concerned with the scientific projects and problems of the IMC mineralogists.

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2. Structure and Staff

The whole range of operative activities of IMC is organized in four structural units (three research departments and service laboratory department), adminis-trative group and subsidiary staff.

IMC – Organization chart

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2.1. Short description of the structural units

Department “Topographic Mineralogy”Research Topics– Mineral Systems– Technogenic SystemsResearch Activity– Studying mineral objects formed in natural gradient systems aiming at the

development of genetic models and their practical applications– Studying the phase composition, qualitative characteristics and distribu-

tion of components in technogenic systems formed in using mineral raw materials as well as their impact on the environment

– Creation and actualization of mineralogical data basesMain Research Objects: magmatic and metamorphic rocks; fluorite and bar-

ite deposits; sedimentary exhalative polymetallic deposits; metalliferous sediments from ocean rift zones; coals and products of their combustion; waste products from power engineering, metallurgy and ore dressing; agates; platinum-group minerals; accessory minerals; heavy minerals concentrates; archaeological artifacts.

Department “Experimental Mineralogy and Crystallography”Research Topics– Synthesis and Crystallization of Minerals and Materials – Modeling of Natural Processes and SystemsResearch Activity– Synthesis and crystallization of minerals and materials in model systems– Investigation of products and processes of their formation– Experimental modeling of natural processes in gradient fieldsMain Research Objects: microporous materials, natural zeolites, tungsten

minerals, bentonites, phosphorites, sorbents based on clays and zeolites, tita-nium and zirconium silicates, basaltic glasses, catalysts, laser optics grade single crystals.

Department “Structural Crystallography”Research Topics– Crystal Chemistry– Physics of MineralsResearch Activity– Determining of the crystal structure, phase and chemical composition and

properties of minerals, single crystals, crystalline and polycrystalline materials

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– Synthesizing of new chemical compounds with particular structures and properties

– Completing crystallographic and spectroscopic databases for minerals and materials

Main Research Objects: optical crystals and glasses, new crystalline materi-als, zeolite type materials and thin films.

Service Laboratory Department– Laboratory of Electron Microscopy: (i) local investigations of the morpholo-

gy, preferred orientation, phase and chemical composition, textural relationships, structural defects and structure of inorganic natural and synthetic phases, nano-sized materials and thin films using various techniques of transmission electron microscopy; (ii) quantitative and qualitative characterization (morphology, micro-structure, chemical composition, phase and chemical inhomogeneities) of mas-sive, dispersed, polished and non-polished minerals, rocks, synthesized phases, thin films and other materials including biological tissues using scanning electron microscopy and electron microprobe analysis.

– Laboratory of X-Ray Diffraction Analysis: (i) determining unit-cell param-eters, space group symmetry and atom positions in the structure of crystalline phases by X-ray single crystal diffraction analysis; (ii) X-ray powder diffraction analysis with possibilities for: qualitative phase analysis, unit cell parameters re-finement, profile analysis of peaks, structural analysis of polycrystalline phases by the Rietveld method, quantitative analysis of natural and synthetic materials.

– Laboratory of Spectroscopy: measuring spectra of optical absorption in the mid-, near-infrared, visible and ultraviolet regions.

– Laboratory of Thermochemistry: determining phase transition tempera-tures, chemistry of thermal reactions, kinetic and thermodynamic parameters of reactions and phase transitions in TG, DTG, DTA, and DSC regimes.

– Laboratory of Experimental Mineralogy and Crystal Growth: (i) low tem-perature (up to 200°C) hydrothermal synthesis of microporous and layered mate-rials; (ii) crystal growth by the Flux method; (iii) high temperature electrochemical experiments in melts; (iv) crystal growth (up to 1660°C) by the Bridgman Stock-barger method (Crystallox); (v) synthesis of ceramic and polycrystalline compos-ites through hot pressing (Crystallox) (up to 1500°C and to 100 MPa pressure).

– Chemical Laboratory: analyses of rocks, ores, waste waters and techno-genic products by standard analytical methods and atomic absorption analysis.

– Laboratory of Optical Microscopy: study of rocks, ores, minerals and tech-nogenic products in reflected and transmitted light with possibilities for obtaining

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digital images by polarizing microscopes Leitz Orthoplan and Jenapol, micro-hardness tester PMT-3 and binocular lenses.

– Laboratory of Samples and Preparations: crushing, milling, sieving anal-ysis, separation, preparation of polished plates and samples, thin and polished sections.

2.2. Staff2.2.1. Board

− Director: Dr. Zhelyazko Damyanov− Deputy Director: Dr. Ludmil Konstantinov− Scientific Secretary: Dr. Mihail Tarassov

Department “Topographic Mineralogy”− Head: Dr. Eugenia Tarassova− Staff – 12

Department “Experimental Mineralogy and Crystallography”− Head: Dr. Ognyan Petrov− Staff – 9

Department “Structural Crystallography”− Head: Dr. Ludmil Konstantinov− Staff – 9

Service Laboratory Department:− Head: Dr. Ludmil Konstantinov− Staff – 9

Administration:− Chief – Boris Marinov, Dipl. Eng. – till March 2010

Valeri Genov, MSc. – since April 2010 − Chief Accountant – Kristian Christov, MSc – till October 2010

Krasimira Gavrilova - since November 2010− Staff – 5

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2.2.2. Scientific Council Dr. Ludmil Konstantinov – ChairmanDr. Mihail Tarassov – Vice chairmanDr. Vilma Petkova – SecretaryDr. Boris Shivachev – since September 2010Dr. Christina VassilevaDr. Diana Nihtyanova – since September 2010Dr. Nadia PetrovaDr. Ognyan PetrovDr. Oleg VitovDr. Rossitsa NikolovaMSc. Virgil DimovDr. Vladislav Kostov-KytinDr. Yuri KalvachevDr. Zdravko TsintsovDr. Zhelyazko Damyanov

2.2.3. Research Staff

ProfessorsDSc. Stanislav Vassilev

Associate ProfessorsDSc. Bogdana Zidarova – retired since January 2011Dr. Boris ShivachevDr. Boryana MihailovaDr. Christina VassilevaDr. Diana NihtianovaDr. Eugenia TarassovaDr. Irina MarinovaDr. Ivan Donchev – retired since February 2010Dr. Jordan Mouhovski – retired since February 2010Dr. Ludmil KonstantinovDr. Mihail TarassovDr. Nadia PetrovaDr. Ognyan PetrovDr. Oleg Vitov

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Dr. Rossitza NikolovaDr. Vilma PetkovaMSc. Virgil Dimov – retired since October 2010Dr. Vladislav Kostov-KytinDr. Yuri KalvachevDr. Zdravko TsintsovDr. Zhelyazko Damyanov

Assistant ProfessorsDr. Bilyana Kostova – till October 2010MSc. Krasimir KossevDr. Ljubomir DimitrovDr. Nadejda LiharevaMSc. Valentin Ganev

ResearchersMSc. Iskra Atanasova-PiroevaMSc. Lachezar PetrovMSc. Louisa Dimova (self-training PhD student since April 2009)MSc. Lubomira MachevaDr. Milen Kadiyski MSc. Petya NenovaDr. Rossitsa TitorenkovaDr. Stanislav FerdovMSc. Svetlana AngelovaMSc. Valeri GenovMSc. Yana Tzvetanova

PhD studentsMSc. Elena TachevaMSc. Daher DaherMSc. Svilen Gechev – since October 2010

The majority of scientists in IMC have specialized in leading scientific institu-tions in Belgium, Germany (4 fellows of the “Alexander von Humboldt” Founda-tion), Japan, Russia, Spain, Switzerland, USA, etc.

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3. Main Equipment

Laboratory of Electron Microscopy– CARL ZEISS SMT SEM EVO LS25 with EDAX Trident system– Philips EM 420T (120kV) with EDAX 9100/70– Philips SEM 515 with WEDAX-3A– Philips SEM 515– various subsidiary and peripheral devices

Laboratory of X-Ray Diffraction Analysis– Oxford Diffraction Supernova A X-ray single crystal diffractometer

with two X-ray sources and Oxford Cryosystems Cobra temperature attachment

– Enraf Nonius 586 CAD 4 X-ray single crystal diffractometer – Bruker AXS - D2 Phaser X-ray powder diffractometer– DRON 3M X-ray powder diffractometer with PC-based system for

phase identification– specialized data processing software, full ICDD database and struc-

ture databases ICSD, CSD, and PDB

Laboratory of Spectroscopy– Bruker FT-IR spectrometer Tensor 37 with HYPERION 2000 FT-IR

microscope– Varian UV-VIS spectrophotometer CARY-100 Scan

Laboratory of Thermochemistry– SETARAM SETSYS 2400 TGA-DTA/DSC system with PFEIFFER

OmniStar mass spectrometer/gas analyzer – Stanton Redcroft differential scanning calorimeter DSC 1500– Stanton Redcroft differential thermal analyzers STA 781 and DTA 675 – Stanton Redcroft thermomechanical analyzer TMA 790

Laboratory of Experimental Mineralogy and Crystal Growth– Low temperature (up to 150°C), low pressure (up to 5 MPa) hydro-

thermal crystallization– Melt growth by the Bridgman-Stockbarger method (Crystalox)– Flux growth– Hot-pressing (up to 1500°C, up to 100 MPa) (Crystallox)– Furnaces of different type up to 1600°C

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4. Research Topics4.1. Mineral systems and mineral genesis

1. Pertsevite-(OH), a new mineral in the pertsevite series, Mg2(BO3)1–x(SiO4)x

(F,OH)1–x(x < 0.5), from the Snezhnoye deposit in Sakha-Yakutia Republic, Russia (I.O. Galuskina, L. Ottolini, M. Kadiyski, Th. Armbruster, E. V. Galuskin, P. Dzierżanowski, A. Winiarski)

Pertsevite-(OH), end-member formula Mg2(BO3)(OH), is a new mineral found in a ludwigite-kotoite magnesian skarn from the Snezhnoye deposit in Sakha-Yakutia Republic, Russia [14]. The Commission on New Minerals, No-menclature and Classification, IMA (IMA 2008-060) has approved the mineral and the mineral name. Moreover, the Chairman of the CNMNC agreed to re-naming pertsevite to pertsevite-(F). The two minerals constitute the pertsevite series with the general formula Mg2(BO3)1–x(SiO4)x(OH,F)1–x, where x = 0.1–0.3. Pertsevite-(OH) is biaxial: 2Vz = 55–65°(meas), 2Vz = 75°(calc); α = 1.611(1), β = 1.623(1), γ = 1.644(1)°; X = b, Y = c, Z = a. It is associated with kotoite, szaibely-ite, ludwigite-azoproite, clinohumite, hydroxylclinohumite, forsterite, chondrodite, calcite, REE-bearing sakhaite, sphalerite, and goethite. Ion microprobe analy-ses of pertsevite-(OH) using secondary ion mass spectrometry gave B, F, and H contents consistent with B and F contents determined by electron microprobe analyses (EMPA), and with OH contents calculated from EMPA data, confirm-ing that OH/F ratio > 1 in pertsevite-(OH). Pertsevite-(OH) is orthorhombic, with

Fig. 1. Pertsevite-(OH) (Pv) associated with ludwigite (Ldw), kotoite (Kot), REE-bearing sakhaite (Skh), calcite (Cal), BSE image, low

vacuum, 0.3 Torr.

Fig. 2. Classification diagram forsterite-pertsevite-(OH)–pertsevite-(F). 1 = pertsevite-(F) from Naled-noye (type locality, Schreyer et al. 2003), 2 = pertsevite-(F) from Titovskoye (Schreyer et al. 2007), 3 = pertsevite-(OH) from Snezhnoye (this study and Galuskina et al. 2008), 4 = pertsevite-(F) from Snezhnoye (Galuskina et al., 2008).

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space group Pnma. Cell dimensions refined from X-ray powder diffraction data are as follows: a = 20.499(1), b = 11.900(1), c = 4.589(1) Å, and V = 1119.4(3) Å3. The strongest lines of the X-ray diffraction pattern are [(hkl), d-spacing in Å, (I)]: (331) 2.7480 (61), (141) 2.4788 (42), (711) 2.4197 (35), (441) 2.2455 (86), (801) 2.2408 (45), (442) 1.7124 (100), (802) 1.7074 (47), and (12.4.0) 1.4817 (51). The main bands in the FTIR spectrum of pertsevite-(OH) are 1354, 1261, 1178, 1022, 975, 929, 888, 745, 555 and OH-specific 3696, 3562, 3530 cm–1.

2. Spinel accessories in ultramafic and mafic rocks from Gega ophiolite melange in Ograzhden Mountain, SW Bulgaria (P. Ivanova, N. Zidarov)

Spinels are often used as reliable “petrogenetic indicators” because they crystallize at a wide range of conditions present in mafic and ultramafic magmas, and often they are among the first phases to crystallize.

Relicts of accessory spinels from spinel (MgAl2O4) – hercynite (FeAl2O4) series are observed in the mafic and ultramafic rocks belonging to the Gega melange body (GMB), cropping out near the western frontier of Bulgaria at the village of Gega in the southern part of Ograzhden Mountain.

In this communication newly acquired data about the chemical composition of these spinels are presented and their significance for reconstructing the petro-genesis of their mother rocks is discussed [18, 115].

Geological setting. Blocks of unaltered or amphibolitized to various degrees ma-fic and ultramafic rocks hosted in the cores of the amphibolitic boudines constituting a tectonically reworked metabazite body (GMB) crop out on an area of 0.7 km2. They are pyroxene megacrysts bearing spinel pyroxenites together with coarse grained olivine gabbro-norites, cross-cut by aphyric gabbro-noritic dykes, coarse to medium grained leucocratic pyroxene gabbro, serpentinized peridotites and/or harzburgites. They form a fragment of boudinated ophiolitic complex preserved in the axial part of recumbent fold of two-mica gneisses ± kyanite and garnet.

Mineralogical data. The relicts of accessory spinels are established in the spinel pyroxenites with the clynopyroxen megacrysts (clynopyroxenites and web-sterites), in the olivine gabbro-norites and in the aphyric gabbro-noritic dykes.

The spinels are green and their individuals (up to 0.5 mm) have irregular to crescent form or V-shaped outlines. In the clynopyroxenites they are disposed in and around orthopyroxene grains or intergrow simplektitely with exsolved or-thopyroxene together with magnetite. The associated minerals are:

in clynopyroxenites – Cpx, En, Chr, Ilm, Mt ± Pl ± Ol;• in olivine gabbro-norites – Ol, Cpx, En, Pl, Ilm, Mt;•

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in gabbro-norites – Di, En, Pl (An• 53), Ilm, Mt.Microprobe analyses of spinels (Philips SEM 515 with Wedax-3A, 5-10 nA,

15-18 kV) were performed on clynopyroxenites (5 samples), olivine gabbro-norites (10 samples) and gabbro-norites (7 samples). The empirical formulae, in which Fetot is divided to Fe2+ and Fe3+ by the method of Nenova (1997) are calculated and the following ratios are obtained:

clynopyroxenites: (Fe2+

4.93–6.11Mg2.77–3.55Na0–0.48Ca0–0.18Mn0–0.2Zn0–0.21)7.7–10.55

(V0–0.03 Ti0–0.3Fe3+0–0.1Cr0.06–0.43Al13.97–15.32Si0–0.7)14.03–16.52O32;

Fe2+/(Mg + Fe2+) = 0.59–0.69; Cr/(Cr + Al) = 0.004–0.03; Mg*100/(Mg+Al) = 31.19–41.26.

olivine gabbro-norites: (Mg4.17–5.02Fe2+

3.51–4.24Ca0–0.06Mn0–0.2Zn0–0.26)7.68–9.64 (Fe3+

0–0.03Cr0–0.4Al14.93–15.64Si0–0.28)14.93–16.36O32;Fe2+/(Mg + Fe2+) = 0.43–0.51; Cr/(Cr + Al) = 0–0.026; Mg*100/(Mg + Al) = 49.47–57.50.

gabbro-norites: (Fe2+

4.08–6.11Mg2.39–4.04Na0–0.14Mn0–0.06Zn0–0.05)6.47–10.04 (V0–0.14Ti0–0.55Fe3+

0–0.02Cr0.03–0.25Al14.26–15.91Si0–0.23)14.29–17.10O32;Fe2+/(Mg + Fe2+) = 0.46–0.71; Cr/(Cr + Al) = 0.0019–0.016; Mg*100/(Mg + Al) = 28.60–49.50.

Zn, Mn, Ca, Na, V and Si are minor elements in the investigated spinels.Discussion. The compositions of the spinels are indicative for the conditions

of their crystallization, tectonic environment and the origin of the magmas, which formed the rock association in GMB. Most important in this respect are the ratios Fe2+/(Mg+Fe2+), Cr/(Cr+Al), Mg*100/(Mg+Al), and Al partitioning between olivine and spinel.

The established increasing of Fe3+ and of the Fe2+/(Mg+Fe2+) ratio can be attributed to the evolution of spinel compositions during fractional crystallization of olivine or pyroxene from the host magma. This increases the Fe/Mg ratio of the melt. Presumptively, in our case, this is emphasized by the reaction between spinels in orthocumulate rocks and evolving trapped intercumulus magma. The variation in Fe2+/(Mg+Fe2+) ratio, has two sources: evolving melt composition dur- ratio, has two sources: evolving melt composition dur-ing crystallization, and the exchange between Fe2+-Mg of the spinels and coexist-Mg of the spinels and coexist- of the spinels and coexist-ing silicates (usually olivine), which favours increasing Fe2+/(Mg+Fe2+) ratio in the spinels with falling environmental temperature. This effect is most highlighted in slowly cooled rocks (like megacrystic spinel pyroxenites of GMB).

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Mg-Al compositions are characteristic for HP conditions, where spinel com-positions are being controlled by Al exchange with coexisting pyroxenes. The low Cr/(Cr+Al) ratio might result from clynopyroxene-spinel subsolidus equilibration where a significant amount of Al is exsolved from clynopyroxene in order to form aluminous spinel.

It can be assumed that spinels in olivine gabro-norite correspond to spi-nels equilibrating with olivine of constant composition and constant temperature ~ 1353°C. This value is calculated by the olivine-spinel geothermometer based on Al partitioning between olivine and spinel.

The principle constituents in spinels behave very differently during fractional crystallization or partial melting, with Cr and Mg strongly partitioned into the solid, and Al strongly partitioned into the melt. Partitioning of Mg and Fe2+ between spi-nel and silicate melts and minerals is strongly dependent on temperature and the ratio of Fe2+ to Fe3+ is sensitive to variations in fO2.

The grain to grain variation of spinel’s composition is most likely caused by reequilibration with adjacent silicates during cooling process.

The investigated spinels from GMB fall in the category of plutonic ultramafic and some mafic cumulate rocks of oceanic affinity, following classification scheme for spinel composition in mafic and ultramafic rocks of Barns and Roeder. This cat-egory includes tectonically emplaced high-pressure and high-temperature “Alpine” ultramafic bodies of probably ophiolitic affinities in orogenic belts. For these rocks the triangle Fe3+–Cr–Al diagram points to the Al-rich spinels of high-pressure spinel lherzolite bodies, which are characterized by lower values of Fe2+/(Mg+Fe2+) ratio, reflecting the high-temperature of equilibration with olivine. For GMB pyroxenites, olivine gabbro-norites and gabbro-norites this ratio is between 0.042 and 0.72 and for the Fe3+/(Fe3+ + Cr+Al) ratio – between 0.005 and 0.002.

Conclusion. The newly acquired data for the chemical composition of these spinels confirm our formerly expressed opinion based on petrochemistry and petro-graphy of the rocks, that GMB represents tectonically dismembered ophiolite body formed under high pressure – high temperature conditions of the Upper Mantle.

3. First find of nephrite in tremolitite body from Ograzhden Mountain, SW Bulgaria (N. Zidarov, R.I. Kostov, P. Zidarov)

Nephrite is a fiber cryptocrystalline massive variety with composition in the tremolite Ca2Mg5Si8O22(OH)2 to ferroactinolite Ca2Fe5Si8O22(OH)2 amphibole series. Nephrite deposits are associated worldwide mainly with serpentinite units within ophiolite belts or with dolomite marbles as a product of metasomatic processes.

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Nephrite takes a specific role in the history of human civilization. It is one of the first mineral raw materials used for prehistoric stone tools (axes, adzes and chisels), prestigious insignia, amulets and other jewellery artefacts. Nephrite artefacts are found on the Balkans with highest concentration on the territory of contemporary Bulgaria, from the Early Neolithic to the end of the Chalcolithic pe-riod (end of VII mill. BC – middle of V mill. BC), which is the reason for introducing a Balkan “nephrite culture”, probably one of the earliest in mankind, even earlier than the well known Chinese Neolithic nephrite yielding cultures. On the territory of Bulgaria such nephrite artefacts are found mainly in the prehistoric sites along the Struma River valley, in Central Bulgaria, the Eastern Rhodopes and in North-eastern Bulgaria. Despite the numerous nephrite archaeological finds on the Bal-kans, no in situ deposits or occurrences have been described in geological or mineralogical papers. The geological setting for such deposits and occurrences in Bulgaria and some other Balkan countries is favourable with a lot of serpenti-nized ultramafic rock outcrops. The observation and description of an occurrence of nephrite bearing tremolitite body [77, 78, 160], gives a hint for the idea that in SW Bulgaria there are conditions for the formation and future finding of nephrite deposits related to the rocks of the ultramafic genetic type.

Occurrence. Nephrite is found among the minerals of a small talc-tremolitic body included in metamorphic rocks cropping out in the Ograzhden Mountain, along the Lebnitsa River valley.

Geological setting. The investigated talc-tremolitic body is incorporated in non-uniformly migmatized biotite gneisses (metagranites with a protolith age ~ 460 Ma) constituting the metamorphic complex, building the Ograzhden unit of the Serbo-Macedonian Massif to the west of the Struma River. They are metamorphosed in the amphibolite facies with a Variscan age (336±3.7 Ма ac- in the amphibolite facies with a Variscan age (336±3.7 Ма ac-in the amphibolite facies with a Variscan age (336±3.7 Ма ac- the amphibolite facies with a Variscan age (336±3.7 Ма ac-the amphibolite facies with a Variscan age (336±3.7 Ма ac- amphibolite facies with a Variscan age (336±3.7 Ма ac-amphibolite facies with a Variscan age (336±3.7 Ма ac- facies with a Variscan age (336±3.7 Ма ac-facies with a Variscan age (336±3.7 Ма ac- with a Variscan age (336±3.7 Ма ac-with a Variscan age (336±3.7 Ма ac- a Variscan age (336±3.7 Ма ac-a Variscan age (336±3.7 Ма ac- Variscan age (336±3.7 Ма ac-Variscan age (336±3.7 Ма ac- age (336±3.7 Ма ac-age (336±3.7 Ма ac- (336±3.7 Ма ac-ac-cording to data of the U-Pb method for xenotime), and in certain episodes are related to the Alpine magmatic activity and change of the tectonic regime, with a lower in degree metamorphism. In some parts of the metamorphic complex garnet-mica schists, metamorphosed ultramafic and mafic rocks (serpentinized peridotites and/оr harzburgites, clinopyroxenites and websterites, olivine gab-, olivine gab-olivine gab-bro-norites and leucocratic gabbros) are registered, which are metamorphosed to eclogites and latter on to amphibolites. The Igralishte and Nikudin granitoid plutons with an age about 243 Ma as well as volcanic dacitic bodies about 32 Ma old are intruded in the metamorphic complex.

Description of the talc-tremolite body. The talc-tremolite body (Fig. 1) is elon- talc-tremolite body (Fig. 1) is elon-talc-tremolite body (Fig. 1) is elon--tremolite body (Fig. 1) is elon-tremolite body (Fig. 1) is elon- body (Fig. 1) is elon-body (Fig. 1) is elon- is elon-is elon- elon-elon-gated in a northwest-southeast direction with a lens shape form. Its length is about

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10 m, width in the central part – 2–2.5 m and at the terminal parts – 0.5 m. It is sub-concordant with the host biotite gneisses, which envelop it, and their crystallization schistosity is subparallel to the outline of the body and its schistosity, dipping to the north-east at a ~70o angle. At the lower contact of the body an up to 10 mm thick biotite zone with striations is observed, giving evidence for its tectonic transport, as well as small biotitized amphibolite lenses. The body has a zonal composition with two main zones: Talc zone which is built by talc (about 90%), prismatic tremo-lite individuals, nestiform segregations of sericite, radiate margarite flake aggre-gates and muscovite flakes; Chlorite-margarite-tremolite zone which constitutes the larger part of the body. The colour of this zone is green to yellow-green, with a radiated structure and a combination of nematoblastic, sheaf-like and fibroblastic texture. The tremolite (75–80%) is observed as long to fine prismatic aggregates. Among the latter fine fibers (nephrite) are observed. The margarite (about 20%) is distributed in nests as radiated aggregate flakes. Relict amphibole and Mg-Fe chlorite, as well as biotite flakes in the tremolite at the lower part of the body are also observed.

According to the mineral composition, the described aggregate can be de-noted as nephrite bearing tremolitite.

Mineralogical data. The tremolite and actinolite aggregates are hetero- tremolite and actinolite aggregates are hetero-tremolite and actinolite aggregates are hetero- aggregates are hetero-aggregates are hetero- are hetero-are hetero- hetero-hetero-grained, built by prismatic individuals. Most of the grains are elongated in one and the same direction, but there are also some which are orientated oblique or under an angle toward the elongation. They are cracked along and across their

Fig. 1. Geological sketch showing zonality and mineral distribution in the talc-tremolite body from the Lebnitsa River valley.

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elongation. Needle like individuals with a length up to 1.5 cm are observed, as well as aggregates with radiated or sheaf-like texture. Under the microscope in thin sections the tremolite is transparent, colourless to pale green (in the richer to iron individuals), which causes a spotted distribution of the graygreen colour. The extinction angle c:Z varies from 15–18° in tremolite to 19–20° in actinolite.

Areas with a nephrite (nematoblastic, fibroblastic) texture are observed among the aggregates of tremolite, which are distributed in irregular forms or as small lenses with dimension of a few mm2. They are composed by densely inter-They are composed by densely inter- are composed by densely inter-are composed by densely inter- composed by densely inter-composed by densely inter- by densely inter-by densely inter- densely inter-densely inter- inter-inter-locked and twisted fibers, usually gathered in microfiber sheaves, with a cross section of about 2.5 μm and length up to 0.3 mm, and built up by subindividuals, each one with a width below 1 μm – well observed at their free terminal part. Such curved and hair-like fine crystallites are known as trichites. Their genesis is related to the metasomatic replacement of the prismatic tremolite individuals by nephritic whiskers and aggregates. The front of metasomatic replacement is polycentric, in the form of nuclei, which transform into spots with the progress of the process. The nephritization process penetrates along the boundaries of the tremolite individuals and homoaxially along their cleavage planes as well as along some transversely to the elongation cracks.

Chemical composition. The microprobe analyzed areas of the nephrite fib-ers correspond to a composition with empirical formulae

Ca1.936K0.027Mg4.318Mn0.034Fe0.711Ti0.026Si7.912O22(OH)2 andCa1.332Na0.034K0.010Ba0.008Mg4.470Mn0.102Fe1.079Ti0.020Si7.972O22(OH)2.

According to the Mg/(Mg+Fe2+) to Si (per formula unit) classification diagram the amphibole compositions are very close to the tremolite-actinolite boundary of 0.9.

XRD data. The powder XRD analysis reveals that the studied mineral cor- powder XRD analysis reveals that the studied mineral cor-powder XRD analysis reveals that the studied mineral cor- XRD analysis reveals that the studied mineral cor-XRD analysis reveals that the studied mineral cor- analysis reveals that the studied mineral cor-analysis reveals that the studied mineral cor- reveals that the studied mineral cor-reveals that the studied mineral cor- that the studied mineral cor-that the studied mineral cor- the studied mineral cor-the studied mineral cor- studied mineral cor-studied mineral cor- mineral cor-mineral cor- cor-cor-responds to tremolite (compared to PDF 850876). The strongest reflections in the powder diffraction pattern are (d in Ǻ, I observed): 8.35, 100; 4.18, 15; 3.26, 10; 3.11, 60; 2.80, 16.

Mineral forming conditions. The genesis of the body is a result of replace-ment of amphibolites, formed on the basis of Precambrian ophiolites and Cado-mian eclogites in the amphibolite facies during the Variscan metamorphism. The process of diaphtoresis is isochemical and takes place under greenschist facies conditions, related to the activation of the fluid regime at the time of the intrusion of the nearby located Igralishte and Nikudin granite plutons. The nephritization of the tremolite is caused by modulation in its structure and heterogenic nucleation at the defect sites of its structure.

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4. Hydrothermal fluorite-forming processes in the Mikhalkovo deposit (Central Rhodopes, Bulgaria) – Field observation and experimental confirmation (B. Zidarova)

A reconstruction of the fluorite formation in the Mikhalkovo deposit (Central Rhodopes, Bulgaria) has been made [80]. The deposit is of strata-bound type and the mineralization is located in marble beds according to two mechanisms, metasomatic and secretional. A system approach is applied to the field and ex-perimental studies. The theoretical and observed morphology of the crystals, their spatial distribution in the deposit, as well as the sequence of formation of crystal forms are discussed. Experiments have been made to explain each of the min-eral forming processes, and namely, diffusion in solutions and gels, and diffusion metasomatism of marbles, for the metasomatic process, and dissolution, synthe-sis and growth in hydrothermal conditions, gravitational, density and chemical differentiation of the solutions, for the secretional one. The results obtained about the determination of the thermal transfer in the different parts of the region of the deposit, the composition and pH of the fluid inclusions and the composition of the contemporary underground waters allow a reconstruction of the paleorelief. The mineral products from the interaction of the hydrothermal solutions with the host rocks indicate the source of NaF and Na2SiF6 for realization of the different mech-anisms of fluorite formation. The obtained result may be used for prognosis of the richest parts in the deposits, searching of new perspective parts and controlling the width of the mineralized interval in the horizontal sections of the ore bodies.

It has been clarified, that the change of the form of the crystals during for-mation of mineral deposits is subordinated to a steady regularity, related to the consistent evolution of the crystal forms of the minerals, in the transition from one to another form in space and time, which determines their zonal distribution in the mineral deposits. The establishment of a regular evolution of the crystal forms of the minerals opens broad possibilities for reproducing the processes of their for-mation, for determination of the place of the different phenomena in this process and its link with the geological history of the deposits.

According to the concrete knowledge for the evolutional development of the crystal forms of a given mineral the existence and possible place of finding of crystals with a specific form from this mineral can be predicted. When the crystal forms characteristic of the richest parts of the mineral deposits are known, then their purposeful prospection can be made. This will allow to avoid the application of expensive and slower methods for searching of mineral deposits. By studying

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the evolutional regularities in the formation of the crystals in nature, new perspec-tives for knowledge and practical approaches are open.

When crystal forms are lacking, the recrystallization of the marbles can be used for interpretation of the mineral-forming processes in the deposits, as well as for giving prognoses for searching of new mineralization in the region. The com-parison of the data obtained from the spatial distribution of the crystal forms of fluorite formed by secretional way in the deposit with the experimental data for the metasomatic formation of the grain fluorite aggregates reveals the specifics of the hydrothermal processes for the formation of fluorite from the Mikhalkovo deposit at one and the same thermal regime, but from different in content solutions. Marbles are replaced when being preliminary prepared (recrystallized), under the influence of the thermal flow, generated by the Bratsigovo-Dospat rhyolitic sheet and sub-sequently attacked by hydrothermal solutions. They correspond to the productive mining levels, which are separated according to the geological data.

Connections between temperature of formation, REE contents and optical spectra of fluorite from the Mikhalkovo deposit are made for genetical implications and practical significance [101]. The obtained results make possible to evaluate the conditions of formation of fluorite crystals and aggregates, the evolution of the composition in the mineral forming medium and to interpret the nature of the zonality in the crystals, individual bodies and the deposit.

5. Fluid enhanced metamorphic transformations of granitоid rocks into orthoschists, East Rhodopes (L. Macheva, V. Ganev)

The circulation of fluids through shear zones is an important factor influenc-ing both the deformation and the associated changes in rock chemistry. Shear zones characterized by intense fluid-rock interaction typically show significant variations in mineral composition and intense chemical transformations of the whole-rock chemistry, which could be compared with those in metasomatic proc-esses. On the contrary, other authors noted the fact, that in the absence of sub-stantial involvement of fluid transport in the system during metamorphism, the deformation could be considered as an isochemical process and may be accom-panied by minor changes in the chemistry of the rock.

This investigation focuses on the integrated field, microstructural, and geochemical peculiarities of the deformation of metagranitoids within a middle-crustal shear zone in East Rhodopes and their transformation into aluminous schists [34, 130].

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The studied rocks, cropping out in the most southeastern part of Bulgaria are referred to the lowermost tectonic unit of the metamorphic complex in East Rhodopes – the Byala Reka Tectonic Unit. Hercynian in age metaaluminous to peraluminous porphyritic and equigranular metagranitoids constitute the main part of the unit. These rocks have undergone complicated metamorphic history changing from HP/LT to MP/MT, and finally to LP/LT conditions accompanied by heterogeneous deformation preserving lenses of weakly deformed metagrani-toids within more widely distributed mylonitised varieties. In the southern and central part of the unit metagranitoids form a huge body, and in the northern part, between the villages of Konnici and Popsko, they are observed as numer-ous lenticular bodies situated within garnet-bearing two mica schists and gneiss-schists. Mylonite and ultramylonite bands lying parallel to the regional foliation are common in metagranitoids from this area. The relationships between the metagranitoids and two mica gneiss-schists are highly varied, with numerous repeated alternations strongly resembling parametamorphic or volcanogenic-sedimentary terrain. This gave the basis of all previous authors to assume their metasedimentary origin. Our field and mainly microscopic investigations allow us to consider these rocks as orthoschists, which have been derived at the expense of fluid-assisted transformation of metagranitoids in an open system, causing total recrystallization and deep change in the rock chemistry on wide areas. Field evidence for this assumption are: 1) the existence of numerous inclusions of these rocks in the metagranitoids and vice versa; 2) the recognition of gradational transitions between metagranitoids and mica schists occurring within narrow shear zones; 3) the existence of numerous deformed pegmatite and aplite veins within the schists; 4) the existence of microgranular melanocratic enclaves in gneiss-schists strongly resembling enclaves found in metagranitoids. Never-theless, the main arguments about orthometamorphic origin of these schists and gneiss-schists come from microstructural investigations.

Typically, orthoschists are coarse grained mica-rich meso- to melanocratic gneisses to gneiss-schists composed of white mica, biotite, plagioclase (An5–20) porphyroblasts, garnet porphyroblasts reaching up to 1 cm, quartz, and stau-rolite. Accessory minerals are zircon, apatite, rutile, and ilmenite. The texture of the rocks is blastomylonitic to mylonitic. Microscopically, between metagrani-toids and orthoschists was observed a great variety of microstructural transitions which, according to their increasing degree of transformation, could be denoted respectively as protoblastomylonites, blastomylonites, and ultrablastomylonites. The first ones contain relict potassium feldspar porphyroclasts side by side with

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garnet porphyroblasts and increasing quantity of phyllosilicates. In the blasto-mylonites all potassium feldspar porphyroclasts are completely obliterated and replaced by white mica and clear albite porphyroblasts, which, however, pre-serve inherited deformation-induced myrmekite intergrowths, developed at the most strained sites of the former potassium feldspar. Albite porphyroblasts are full of small, worm-like quartz rods, which could be formed by retrograde metamor-phism at the expense of former more basic plagioclase. Staurolite and tourmaline porphyroblasts are also present.

Ultrablastomylonites (true orthoschists) show a thin banded texture and are composed mainly of phyllosilicates, garnet, and quartz, whereas feldspars are rare. Hence, the formation of aligned mica-defined foliation weakens the tec-tonites and further promotes their transformation.

Major and trace element compositions of whole-rock samples were ana-lyzed on fusion glass tablets by LA-ICP-MS technique. Mass, volume, and com-positional changes accompanying deformation were evaluated using the isocon method of Grant (1986). In all isocon plots of the studied rocks Al, Ti, Mg, Zr, and Hf, show a coherent behavior. These elements are considered to be almost immobile in the present case. A volume loss of up to 40% during alteration has caused relative enrichment of rare earth elements, Sc, Cr, V, Ni, Zn, Cu, Nd, and Yb. There is depletion on, Th, Rb, Ba, and Sr, which is in accordance with the breakdown of feldspars and its release.

In addition, the zircon morphology from the studied schists strongly resem-bles that of the zircons from the neighbouring metagranitoids. Zircons with a well-preserved crystal forms, identical with that of zircons from metagranitoids, are common.

Our investigations show that the studied schists and gneiss-schists are de-rived at the expense of ductile heterogeneous deformation of granitoid rocks. The deformation promotes considerable mobility of the fluid phase favoring recrystal-lization accompanied by deep transformation of the rock chemistry as well as material transport to a great distances. Thereby, the process could lead to com-pletely recrystallized rocks, mesoscopically with appearance typical for the mica schists and passing gradually into augen gneisses. The metamorphic differentia-tion in many cases is so intense that the rocks acquire the appearance of banded migmatites and the concentration of some inert components, such as Al, Ti, Fe, and Mg, leads to the formation of aluminum-rich micaceous rocks. Changes of the rocks are carried out in a ductile shear zone under conditions of decreasing temperature and hydration.

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6. Petrology and geochronology of the Vitosha volcano-plutonic edifice, Western Srednogorie, Bulgaria (S. Atanasova-Vladimirova, A. von Quadt, P. Marchev, I. Peytcheva, I. Piroeva, B. Mavroudchiev)

The Vitosha volcano-plutonic edifice crops out in the western part of the Srednogorie structural zone. The plutonic body is composed of abyssal gabbros and anorthosites, hypoabyssal monzonites, syenites and late veins of granosy-enitic composition, intruded in Late Cretaceous volcano-sedimentary sequence. Volcanic rocks are represented by basaltic andesites and andesites.

The major rock-forming mineral phases are plagioclase, K-feldspar, amphi-bole and clinopyroxene. Common accessory minerals include apatite, titanite, magnetite, ilmenite and zircon. Secondary minerals are epidote, tourmaline, chlo-rite, actinolite, adularia and clay minerals.

Plagioclases span much of the crystallization history throughout the magmatic series, generally decreasing in anorthite component from basic to acid plutonic va-rieties. In volcanic rock the plagioclase is in the bytownite–labradorite range.

Potassium feldspar of orthoclase composition is typical for the monzonite and syenite. It forms large crystals, disposed between plagioclase. The orthocla-se is the major carrier for Sr, Ba, Pb, Rb.

Amphibole is the main mafic mineral in all rock types, with Mg# 58–97. In the classification diagram of Leake et al. (1997), the amphibole from the plutonic rock falls in the field of the magnesio-hornblende and ferrohornblende, whereas the amphibole from the volcanic rocks is tschermakite.

Clinopyroxene is a characteristic mineral for all rock types with Mg# 58–84. It forms deep resorption nuclei or single grains with euhedral contours. Composi-tionally it is augite and diopside.

U-Pb single zircon method was used for the precise geochronological dating of the Vitosha volcano-plutonic edifice. Sr and Nd whole rock and Hf–zircon trac-ing have been used to clarify the origin of the studied rocks.

Following U-Pb single zircon age data have been obtained for the plutonic rocks: gabbro 81.58±0.23, monzonite 82.45±0.4 and syenite 79.67±0.76. U-Pb data of single zircon grains from an andesite plot on a discordia with a Paleozoic age.

Strontium isotope data are quite variable, ranging between 0.7044 and 0.7042 in the less evolved gabbro and andesite, through 0.7052 in the mon-zonite, to 0.7091 in the syenite. Nd (80 Ma) values also show a large variation, from 0.37 to 2.74.

The new age data reported here provide that the rocks of the Vitosha pluton range between 82.4 and 79.7 Ma. Chemistry of the parental magma suggests simi-

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larity with the other plutonic suites from the axial part of the western Srednogorie. Compositional variations of the rock-forming minerals indicate calc-alkaline I-type signature for the Vitosha pluton. Sr and Nd isotope data indicate the presence of depleted mantle source for the parental magma, whereas generation of most evolved magmas requires different degree of crystal contamination. The upper dis-cordia intercept U-Pb zircon of Paleozoic age suggest that the contaminant must have been lithologies from the Variscan basement [102].

7. State-of-the-art electronic bibliographic data base on minerals from Bulgaria (V. Kostov-Kytin, R.I. Kostov, P. Ivanova)

The upgrade of the electronic bibliographic data base on the minerals from Bulgaria goes on [123]. It is realized in the form of an electronic table in Microsoft Access medium. In fact, this is an electronic catalogue of the published articles on minerals from Bulgaria within the period 1844–2010. More than 700 new records have been added derived mainly from geological periodicals. Thus, the overall number of the refereed titles exceeds 3500. Two new fields have been added with the mineral names in Bulgarian and English languages. This allows a literary check up on minerals in the cases when their names are not included in the title of the re-spective work. Despite the existing incompleteness and limitations the bibliograph-ic mineralogical database is a fact. The improvement of its quality is a question of time and conscientiousness upon its upgrade by as much as possible specialists.

8. Map of stream-sediment minerals of Bulgaria – 2010 (O. Vitov)

The current knowledge on stream-sediment minerals from the Smolyan ad-ministrative region (Central Southern Bulgaria) was evaluated and the mineralog- Southern Bulgaria) was evaluated and the mineralog-Southern Bulgaria) was evaluated and the mineralog-ical dividing and prognoses for mineral prospecting were compiled based on the stream-sediment data from previous surveys [74, 158]. It was ascertained that 25% of the district territory requires new stream-sediment sampling. The mineral composition of the stream-sediment samples revealed a contrast mineralogical anomaly – a linear margin of NW-SE direction between an area containing thorite and an area containing lead minerals that passes to the south of the towns of Devin, Smolyan and Madan, and that is interpreted as collisional boundary of continental microplates (Fig. 1). Halos of mechanical dispersion of gold are lo-cated symmetrically to that boundary.

A detailed prognosis for gold prospecting in the district at 1:50 000 scale was compiled as well as for tungsten-molybdenum (scheelite, molybdenite), lead (galena), tin (cassiterite) and other mineral deposits.

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Carrying out the task entitled “Chromite distribution in alluvial sands and its relation with ultramafic bodies in Bulgaria”, a database including chemical (wet) analyses of rocks from the ophiolitic complexes in Bulgaria (Haydoutov, 1991; 143 analyses), from mafic rocks worldwide (“Igneous rocks. Mafic rocks”, 1985, in Russian; 1850 analyses), and from volcanic rocks (Macdonald, 1972; 18 analy-ses) was compiled. The variations of chemical composition of igneous rocks from the Balkan-Carpathian ophiolite segment have been modeled (Fig. 2) [72, 159].

Fig. 1. Halos of mechanical dispersion of thorite (ThSiO4) in Smolyan administrative region: a) scheme of sampling and thorite content in the stream-sediment samples; b) probability thorite to be found in squares of 2×2 km within the district; c) full Fourier-model of thorite spatial distribution; d) spatial distribution of the most significant (38%) harmonics (2-2) of the probability thorite to be found in the

stream-sediment samples.

Fig. 2. Model of chemical composition variations of the rocks from the Balkan-Carpathian ophiolite segment (a) and its error (b).

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Mathematical modeling has been performed through determination of the pa-rameters of polynomial model using integrating procedures by intervals [99] and comparison of the results applying the least squares method (Fig. 3).

4.2. Environmental and technogenic mineralogy

9. Mineralogy, geochemistry and environmentally safety application of solid fuels and their combustion and pyrolysis products (S. Vassilev, C. Vassileva, D. Baxter, L. Andersen, I. Kostova, J. Hower, M. Mastalerz, N. Nikolova, D. Daher)

An extended overview of the chemical composition of biomass is pub-lished [69] in collaboration with the Institute for Energy – Joint Research Centre at European Commission. The research included a critical review of literature data for 86 biomass varieties (woody, grass, straw, shells, pits, agricultural and animal biomass, algae, refuse and contaminated biomass, etc.) combined with experimental studies to analyze the chemical composition of various types of biomass feedstock worldwide with a focus on the inorganic elements. Further, the data are compared to similar data for coal. This comparison is of importance when co-processing biomass with coal in existing coal-processing facilities as a potential low-cost way to reduce CO2 emissions. It was found that the chemical composition of natural biomass system is simpler than that of solid fossil fuels. However, the semi-biomass system is quite complicated as a result of incor-poration of various non-biomass materials during biomass processing. It was identified that the biomass composition is significantly different from that of coal and the variations among biomass composition were also found to be greater than for coal. Natural biomass is: (1) highly enriched in Mn > K > P > Cl > Ca > (Mg, Na) > O > moisture > volatile matter; (2) slightly enriched in H; and (3)

Fig. 3. Modeling by y=ax2/exp(bx2) (dotted line) and by y=a+bx+cx2+dx3 (dense line) of relations between CaO and MgO (circles) in volcanic rocks (from Macdonald, 1972) using: a) – integrating by

intervals; b) – least square method.

a b

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depleted in ash, Al, C, Fe, N, S, Si, and Ti in comparison with coal. The general considerations and some problems related to the composition of biomass as a fuel are discussed. The presented research demonstrates that the composition is highly variable due to the high variation in source and origin of both natural and anthropogenic biomass along with variation in modes of occurrence of the inorganic elements. Five groups of inter-correlating elements were found to oc-cur in the natural biomass system, namely: (1) C-H, (2) N-S-Cl, (3) Si-Al-Fe-Na-Ti, (4) Ca-Mg-Mn, and (5) K-P-S-Cl. Although the underlying reasons for these inter-correlations within each group are still being investigated, the identified groups form a natural way to classify the different types of biomass. The clas-sification system is presented below. Since the chemical elements present in a given biomass will determine many of its properties, a classification system according to the elemental composition would be of importance in the advanced and sustainable utilization of biomass and the processing of biomass to bio-fuels and chemicals. For example, among other applications, the system could help to predict the composition and behaviour of inorganic residues, i.e. ashes, formed during combustion and gasification of biomass mixtures.

Petroleum coke (PC) samples from a Syrian Refinery, as well as their ashes (PCA) produced at 800°C were studied preliminary for their chemical and phase-mineral composition [70]. The thermal behavior of these products was also in-vestigated. It was found that elements such as Ni, V, Mo and S have contents several orders of magnitude greater than the Clarke values for coal ashes, and they would be of great industrial interest for recovery from PCA. On the other

Fig. 1. Chemical classification system of the inorganic matter in high-temperature biomass ashes based on 78 varieties of biomass, wt.%.

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hand, a number of toxic and potentially toxic elements (V, Ni, Mo, Cd, Co, Cr, Pb, Zn) have high concentrations in PCA and they could potentially contaminate soils, waters and air during the storage, transport, processing and/or utilization of this product. It was also emphasized that an elucidation of the modes of element occurrence (minerals and phases) in PC and PCA is required in respect to their utilization as energy resource or in order to perform some element extractions.

Mercury capture by fly ash carbon (C) was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Mar-itza East 2, Maritza East 3, and Sliven) [84]. Although the C content of the ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank coal-derived fly ash carbons are more efficient in capturing Hg than fly ash carbons from bituminous-fired power plants. The Hg/C ratio decreases with an increase of C in fly ash, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture in-creases with an increase in Brunauer–Emmett–Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-feed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture.

Feed coal and fly ash samples collected at Republika and Bobov Dol ther-moelectric power plants (TPPs) were studied in order to elucidate the content, distribution and mode of occurrence of mercury, as well as their ability for Hg capture and retention [83]. The coals and fly ashes have been characterized with regard to their petrological and chemical composition, including mercury content, and to their surface area properties. The calculated enrichment factor (EF) shows that the Hg concentrations in the bulk coal samples from Republika and Bobov Dol TPPs are 2.19 and 1.41, respectively, and in some coal size fractions the EF can be up to 4 times higher than the Clarke value. The calculated EF for fly ashes, shows that the Hg concentrations in the bulk samples studied are lower than the Clarke value. The Hg distribution in bulk FAs taken from different rows of electrostatic precipitators of both TPP studied shows well established tendency of gradual increase in Hg content from the 1st to the 2nd and 3rd ESP rows.

10. Utilization of the Kremikovtsi ores: A mineralogical viewpoint based on the available data (Z. Damyanov)

After more than 40 years of intensive exploitation, the mining activity in the Kremikovtsi iron-barite-polymetallic deposit was stopped several years ago and

38

the available mining equipment and infrastructure were sold or partially destroyed in the course of time. In 2010, a 35-year production concession for the Kremiko-vtsi deposit was granted to Celsian Ltd. It is expected the mining activity in the deposit to start anew using new equipment and modern mineral processing tech-nology to ensure optimal and profitable utilization of the Kremikovtsi ores.

The analysis of the available data from the previous long-standing multidis-ciplinary research as well as some preliminary results from the recent studies(*) give a reason to formulate some basic prerequisites for effective utilization of the Kremikovtsi ores:

1. The initial mineral processing technology including magnetizing roasting of a Kremikovtsi iron ore mix (in particular, various limonite subtypes and siderite ore) and low intensity magnetic separation produces products (concentrates) with relatively high metal contents (Fe = 54–57%, Mn = 9–10%) and high Fe recovery (85–90%), but also with contents of some other components (such as S included in barite and base metals – Pb, Cu, Zn) generally unacceptable in terms of the stand-ard market requirements for steelmaking. Using this technological approach, the Kremikovtsi iron ores were successfully processed for more than 30 years produc-ing Fe(+Mn) concentrates further subjected to some additional treatment during the metallurgical processes to remove undesired components, e.g. S and Pb.

Similar results gave the mineral processing technology of polygradient mag-netic separation which superseded the magnetizing roasting in the early 90s of the last century with the main scope to avoid some ecological problems.

2. Mixing different iron ore types and subtypes to unify the average metal/gangue composition of the crude ore, the mineral processing technology and the final quality of the produced iron concentrates, however, gives no best pos-sible and acceptable results because the ore mixing inherits all the mineralogi-cal/chemical features of the source ore types/subtypes including also undesired components, thus transferring the problematic composition of one ore type/sub-type to the whole ore mix (and to the final concentrate).

3. The current mineralogical mapping of the Kremikovtsi open pit accompa-nied with extensive mineralogical studies (still running) as well as the preliminary analysis of data available so far show that it is possible (and necessary) to try a shift from the previous unified approach toward selective approach including mining and processing of particular ore type/subtype and obtaining of iron con-centrates of different grade.

* Damyanov, Z. 2010. Mineralogical study of the Kremikovtsi ores. A short preliminary report. – Unpublished Report under Contract with Celsian Ltd., IMC-BAS, 48 pp.

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4. Based on the available mineralogical data for the Kremikovtsi iron ores, applying selective approach of mining and processing can provide the following possible market products (iron concentrates):

(I) high-grade iron concentrate (Fe = 63–65% and more) – from Hema-tite Ore;

(II) iron concentrate with medium Mn content (Fe = 58–60%; Mn = 3–6%) – from Black Limonite Ore;

(III) iron concentrate with high Mn content (Fe = 50–52%; Mn = 8–12%; Mg = 3–4%; Kb = (CaO+MgO)/(SiO2+Al2O3) > 1) – from Siderite and Limonite-Siderite Ores.

Of course, this differentiation is possible and realizable only if consumers of such a products (II and III iron concentrates) are available on the market.

5. At the current stage of investigations, it seems possible recovery of, at least, a part of the Mn minerals in the Black (high-Mn) Limonite Ore in a separate product – manganese concentrate.

6. Barite, which is generally a useful component, is very undesired in the iron concentrates because of its S content, the metallurgical requirements of which are too low (generally BaSO4 < 0.4–0.5%).

As a first step, the great part of coarse-grained barite aggregates can be eliminated at the stage of ore mining by optical separation of the crushed mate-rial. This option was already proven practically by the specialists of Celsian Ltd. and should be included as a standard mining operation.

7. Barite Ore – 3 market products can be produced:– “heavy” barite for oil drilling industry – from all barite ore bodies in the

deposit;– “white” barite as filler for paper and plastic industry – from barite ore bod-

ies in the Siderite Ore;– “pure” barite for chemical industry (with low Sr content) – from fine-grained

barite disseminated within the Siderite Ore.8. Hematite Ore: A possible approach for obtaining a product with high

quality:– gravity separation at a specific density of about 4.5 g/cm3;– fraction > 4.5 – hematite;– fraction < 4.5 – quartz, clay minerals, carbonates (including Mn-rich ones),

barite and small quantities of siderite and goethite.9. Black Limonite Ore: A possible approach for obtaining a market product

(iron concentrate with medium Mn content):

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– magnetizing roasting under (high?) reduction conditions (to obtain high mag-netic magnetite/maghemite/wüstite phases) and low intensity magnetic separation;

– for obtaining of Mn concentrate, the low magnetic product should be proc-essed by a gravity separation at a specific density of about 4.5 g/cm3 (fraction > 4.5 – Mn minerals of type hausmannite-manganosite; fraction < 4.5 – barite, quartz, etc.);

– aggregates of Mn minerals in this ore subtype are generally coarse-sized (> 0.5 mm), so a detail screen analysis of crude ore and magnetized product should be made to identify the Mn minerals distribution in fractions and to refine the proposed approach.

10. Siderite Ore. One possible approach for obtaining a market product (iron concentrate with high Mn content) includes magnetizing roasting under (high?) reduction conditions (to obtain high magnetic Mg-jacobsite and wüstite-like phas-es) and low intensity magnetic separation.

Except in barite, some quantity of S in the Siderite and Limonite-Siderite Ores are localized in sulfides (galena, chalcopyrite, pyrite, tennantite, tetrahe-drite) generally associated with barite. There exist zones of high contents of base metals (1–2%) in both ore types which should be outlined and the barite-sulfide mineralization should be processed separately.

11. The Ochreous (Yellow) Limonite Ore is composed of very fine-grained intergrowths between secondary iron and manganese minerals and contains base metals impurities (Pb, Cu, Zn) in the main ore mineral, hydrogoethite. So, its effective utilization should be an object of more advanced research including probably hydro- and pyrometallurgical methods.

12. Generally, the mineralogical features of the Kremikovtsi iron ores pre-sume a fine grinding to liberate iron minerals before beneficiation processes – may be more than 40–50% of fraction < 0.074 mm (should be established ex-perimentally).

13. Generally, the approaches proposed above are based on the mineralog-ical features of the Kremikovtsi ores. They should be checked first in laboratory conditions and the optimal parameters should be established experimentally. Ad-ditional refinement is possible/desirable on the basis of the mineralogical control of the experiments.

The purposeful short-time program started by Celsian Ltd. and including field mineralogical mapping, basic mineralogical research, lab experiments and technological investigations must give reasonable answers to the questions/ap-proaches given above.

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4.3. Biomineralogy

11. SEM investigation of morphology and chemical composition of neo-phases formed during Er:YAG laser irradiation of human teeth (E. Tarassova, G. Zhegova, M. Tarassov, M. Rashkova)

In the modern clinic dental practice, laser technique is proposed as alter-native tool to the traditional mechanical rotary instruments for teeth treatment (removal of caries tissues and preparation of cavities for restorations). Laser acts on dental substrate by thermomechanical ablation – vaporization of the substrate water accompanied by micro-explosions causing ejection of inorganic (hydroxya-patite – Ca10(PO4)6(OH)2 containing also Na, K, Mg, Al, Si, Zn, F, Cl as minor elements) and organic materials. In some cases, commonly related to an ex-traordinary power and frequency of laser in combination with an inappropriate cooling of the irradiated place, the laser thermal treatment can cause several side effects in the human teeth as melting, carbonization, the creation of cracks in the surrounding tissues and an increase in the pulpal temperature. All these problems are subject of detailed studies and discussions in numerous recent papers (Delfino et al., 2006; Lee et al., 2003; Moshonov et al., 2005; Bachmann et al., 2004). Much less is known about the neo-phase formation during the laser irradiation of dental tissues.

The goal of the present study is to investigate the morphology and chemi-cal composition of phases formed during Er:YAG laser irradiation of human teeth without cooling (without water spray) at 500 mJ/pulse and pulse frequen-cy of 10 pps. For the purpose series of extracted permanent teeth after laser treatment were coated with gold and studied by scanning electron microscopy at 25 kV (Philips SEM515) and electron probe microanalysis at 20 kV (Philips SEM515-WEDAX-3A) [63, 153].

In our experiments, the Er:YAG laser produced cavities were prepared in the cingulum part of tooth crowns. The cavities are with round shape and diameter of 3 mm affecting enamel and dentine to depth of about 1 mm below the enamel-dentin boundary. Although the internal surfaces of the resulted cavities are not smooth and contain round craters in the enamel, the dentinal tubules are well exposed without smear layers and secondary products related to laser treatment. During the present study, no serious side effects of the laser irradiation were identified in the dentine excepting rare cracks and glassy droplets with size of 3–4 μm and Ca-P-O composition (Ca/P ratio was not exactly specified) occasionally distributed on the surface of the exposed dentine. The laser irradiation effects on the enamel are more pronounced and more variable including:

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– enamel melting and formation of glassy mantle covering the enamel prisms;

– apatite recrystallization (neo-formation of apatite); – formation (condensation from gaseous-sublimated phase) of glassy drop-

lets different in size and chemical composition; – crystallization of neo-phases with composition differing from the Ca-P-O

system. The areas of enamel melting with well developed degasation channels cov- of enamel melting with well developed degasation channels cov-of enamel melting with well developed degasation channels cov- enamel melting with well developed degasation channels cov-enamel melting with well developed degasation channels cov- melting with well developed degasation channels cov-melting with well developed degasation channels cov- with well developed degasation channels cov-with well developed degasation channels cov- well developed degasation channels cov-well developed degasation channels cov- developed degasation channels cov-developed degasation channels cov- degasation channels cov-degasation channels cov- channels cov-channels cov-

ering the enamel prisms (Fig. 1a) are widely distributed as islands in the whole interval of the irradiated enamel – from their upper non-irradiated parts to the boundary with the dentine. In the upper parts of the glassy mantles are found na- the upper parts of the glassy mantles are found na-the upper parts of the glassy mantles are found na- upper parts of the glassy mantles are found na-upper parts of the glassy mantles are found na- parts of the glassy mantles are found na-parts of the glassy mantles are found na- of the glassy mantles are found na-of the glassy mantles are found na- the glassy mantles are found na-the glassy mantles are found na- glassy mantles are found na-glassy mantles are found na- mantles are found na-mantles are found na- are found na-are found na- found na-found na- na-na-nosized 500–700 nm spheres (droplets) with predominant Al2O3 composition. In the deeper parts of the irradiated enamel, clusters of 10–12 μm size consisting of microspheres with diameter of 3–4 μm (Fig. 1b) and predominant SiO2 composi-tion are found among the enamel prisms. Beside the glassy material, the melted enamel mantles contain also areas of distinct apatite recrystallization: the neo-formed apatite crystals are with length to 8 μm and width to 1μm (Fig. 1c). The neo-formed apatite shows much higher concentration of K and Al than those in

Fig. 1. SEM photomicrographs of enamel surface after Er:YAG laser irradiation without water cooling: (а) areas of enamel melting with well developed degasation channels; (b) clusters of microdroplets with silica composition among enamel prisms; (c) neo-formed apatite crystals; (d) needle-like crystals of К2SО4 among neo-formed apatite. (original magnification: a) x4545; b) x2045; c) x1250; d) x2500;

e) x10000)

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the hydroxyapatite from the non-radiated enamel. Among the neo-formed apatite aggregates and mantle are situated evaporation cavities, Ca- phosphate droplets (3–4 μm) and rarely star-like intergrowth of needle crystals with predominant K and S composition (Fig. 1d).

During the performed investigation of Er:YAG laser irradiated human teeth without cooling it was found that:

– the side effects of the laser irradiation are more pronounced in the tooth enamel and hardly identified in the dentine;

– although the predominant part of the observed side effects of the laser irradiated enamel (melted enamel, glassy droplets, recrystallized apatite) are di-rectly related to the initial dental hydroxyapatite and its major components – CaO and P2O5, the observed droplets of predominant Al or Si composition as well as the neo-crystals of K and S suggest that during the laser treatment some minor elements of the initial dental apatite can be fractionated and segregated; some similarities to this process can be seen also in the increase of K and Al in the com-position of neo-formed apatite; all these chemical changes need further detailed investigation;

– the major result of the laser treatment of dentin is total ablation of its material that ensures good exposing of dentinal tubules not covered by smear layers; the attained ablation effect can be related to the intrinsic low density, high porosity and essential water content of the dentin especially as compared to the enamel which favor the total laser ablation of the material; the latter is in accordance with the fact that the wavelength 2.94 μm typical for Er:YAG laser is highly absorbed by water.

12. Biomimetic transformations of amorphous calcium phosphate – ki-netic and thermodynamic studies (D. Rabadjieva, R. Gergulova, R. Titoren-kova, S. Tepavitcharova, E. Dyulgerova, Chr. Balarew, O. Petrov)

The biomimetic synthesis and phase transformation of XRD amorphous calcium phosphate were studied by application of kinetic, chemical and spec-tral (XRD and IR) methods and thermodynamic simulations. Two simulated body fluids (SBFc and SBFr), differing in their HCO3

– and Cl– ion contents, were used in the maturation studies. It was proved that the biomimetic maturation acceler-ated the phase transformation of less thermodynamically stable amorphous cal-cium phosphate to poorly crystalline hydroxyapatite. Few regularities were found: (i) kinetic reasons determined the biomimetic precipitation of XRD-amorphous calcium deficient phosphate (ACP); (ii) the precipitated ACP always contained

44

impurities due to co-precipitation, ion substitution and incorporation phenomena; (iii) the increased content of HCO3

– ions in the surrounding microenvironments increased the rate of phase transformation and the concentration of MeHCO3

+ (Me=Ca, Mg) species in the solution, but decreased the solubility of CaCO3 only and accelerated its precipitation, thus playing a crucial role in the process under study [52].

4.4. Archaeomineralogy

13. Archeometrical studies of gold artifacts from the Early Bronze Age (EBA) from Dubene Archaeological Site (Z. Tsintsov, M. Hristov, S. Tsane-va, V. Karatsanova)

At the end of 2010 the project under contract TK SKIN – 4/2007 entitled “Archeometrical studies of gold artifacts from the Early Bronze Age (EBA) – the Dubene Archaeological Site”, funded by the Bulgarian National Science Fund, Ministry of Education, Youth and Science, was completed. The studies of vari-ous objects from the Bronze Age in the recent years significantly helped to raise the “veil” of the unclarity associated with the culture and occupation of the com-munities who lived during that time in our lands. Particularly important for the contemporary science, however, are the studies related to the achievements of the ancient masters in technological plan and an important aspect among these is the processing of gold – the symbol of the formation and development of the civilization [96, 97, 98, 156].

The lack of systematic technological studies on the processing of gold from the formation and initial development of the civilization is a serious obstacle for the objective comparison of the level of technological development, of the tradi-tions and the specific peculiarities in the processing of this metal by different cultures. The Dubene Archaeological Site found in 2004 with its 25 rite structures, some of them keeping more than 21 000 gold objects, provides a great opportu-nity to “throw” more clarity on the problem. Almost all artifacts from the site were preliminary examined under binocular stereomicroscope and for the study a rep-resentative extract of about 500 objects was separated, which were then divided into three species – separators, beads and spirals. Further, a partially molten aggregate of elements for an adornment was found, including a thick bead and several (at least seven) thin circular beads. So far, the results for the production technology, the nature and the peculiarities of the separators and the partially molten aggregate are summarized (Fig. 1).

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The studies have shown that the primary rough surfaces of the objects of different types are characterized by similar micro block construction. It is most probably formed by sintering (powder metallurgy) of fine placer gold, in order to obtain an initial monolithic gold aggregate. In this process the monolithic nature of the aggregate is achieved at temperatures considerably lower (about 600–650°С) than the melting point of gold (about 1062°С) without melting the metal itself. The method is much simpler than casting as practically there are no pro-duction losses of material, it is easily reproduced and allows mass production of relatively uniform elements. The modeling of the individual articles was done by mechanical compaction and plastic deformations, resulting in hammering, extru-sion, smoothing, polishing, bending, twisting, folding, scratches, etc. The artifacts are made of alloys formed in the binary system Au-Ag with a strong dominant role of Au. Rarely the system is three-component with Cu added to the above two elements.

Remains of textile fibers probably remained from the strings are found in the holes of one of the separators. SEM-studies showed that these are fibers of raw cotton (Fig. 2). It is known that cotton is used even earlier in the lands of today Pakistan and around. According to literature data, that early use of cotton

Fig. 1. Golden artifacts from Dubene Archaeological Site: separators – massive (a), complexes (b); partially molten aggregate of elements for an adornment (c). SEM – (c); Scale

bar – 1 mm (c).

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is reported also for the lands of neighboring Greece. The textile fibers found in our studies for the first time prove the use of cotton also in our lands back in the third millennium BC.

Interesting results were obtained in the study of many small (lengths of about 1.5 mm) seeds found in a complex of objects covered in two ceramic ves-sels. The specialized study showed that these are seeds, carried by the fluff of rush (Fig. 3).

In conclusion, it should be noted that the repeating “picture” of technologi-cal features on the surface of the artifacts gives grounds to assume that certain sequence was followed in their production, a tradition that enabled the ancient masters to make many almost identical products. These results will allow to build a database for the manufacturing processes and composition of gold from the

Fig. 2. SEM images of raw cotton fibers from Dubene Archeological Site. Scale bar – 0.1 mm (a, b).

Fig. 3. SEM images of seeds, carried by the fluff of rush from Dubene Archeological Site. Scale bar – 0.1 mm (a, b).

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Early Bronze Age with important benchmark role in the research and the com-parative studies of gold objects from archaeological sites of the same or close historical period. Furthermore, the documented basic technological characteris-tics and features of the artifacts can be used as objective criteria for determining the authenticity of similar items to differentiate them from fakes.

4.5. Modelling and modification of mineral systems

14. Preparation and Rietveld refinement of Ag-exchanged clinoptilolite (L. Dimova, O. Petrov, M. Kadiyski, N. Lihareva, A. Stoyanova-Ivanova, V. Mikli)

Clinoptilolite is a natural zeolite that can be used as a carrier of cations like Zn2+, Cu2+, Ag+, etc. with pronounced antibacterial effect.

The purpose of the present study is studying the conditions for a com-plete Ag-exchange of sedimentary clinoptilolite and refining the structure by the Rietveld method from powder XRD data collected on a conventional dif-fractometer [6, 81, 104].

The initial sample (Beli plast deposit, Bulgaria) was enriched in clinoptilolite by a sequence of treatments: crushing, sieving, sedimentation, and separation with heavy liquids to obtain a content of about 93 wt.% of clinoptilolite and intergrown opal-C. Opal-C was consequently removed by chemical treatment with NaOH. The final virtually pure clinoptilolite sample (> 98 wt.%) was labeled as R2.

Fully exchanged silver-clinoptilolite was obtained in 1M AgNO3 water solu-tion. The exchange was done using Teflon autoclaves at 100°С for 8 days, by replacing the solution each day and taking a fraction of the material for analysis at each of these steps. The maximum Ag-exchange was reached on the 7th day (4.86(4) Ag atoms per formula unit).

The AAS data for the Ag-exchanged clinoptilolite showed an Ag content of 18.39 wt.% after the 8th day of the applied exchange procedure. The exchanged sample shows an increase of the content of Ag+ from 0 to 14.59 wt.% (for the first day) and from 14.59 to 18.39 wt.% (during the period from the first to the 8th day). The Ag-content for the 7th and the 8th day is almost equal (Fig. 1).

As the conditions for maximum Ag-exchange were defined, we performed an ICP analysis for samples L2 and R2 and for their Ag-form. The corresponding calculated crystal chemical formulae are:

(Na0.23Ca1.39K1.52Mg0.46)Al5.68Si30.18O72·20H2O (with opal-C)(Na0.07Ca0.09K0.28Mg0.22Ag4.86)Al6.14Si29.86O72·18.57H2O for Ag sample without opal.

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On the basis of the afore-mentioned experimental findings, one can infer that our clinoptilolite is almost fully exchanged with Ag cations, providing samples suitable for detailed structural analysis by the Rietveld method.

A Rietveld structural refinement was then performed for the Ag-exchanged clinoptilolite, and three independent silver sites were localized in the channels of the clinoptilolite structure. We located seven water sites coordinating the Ag-sites (Fig. 2). Ag-clinoptilolite can represent a promising low-cost antibacterial mate-

Fig. 1. AAS data of Ag content vs. time and powder XRD intensity of the 020 reflection.

Fig. 2. The tetrahedral framework of Ag-exchanged clinoptilolite, sample L2-Ag. Sizes of spheres correspond to site occupancies, larger spheres have larger population.

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rial. The most populated is the Ag2 (with 1.84(4) apfu) in the eight-member rings forming the B channel (parallel to the c axis). The coordinating water sites are at distances of 2.54(5) and 3.34(6) Å (W3) and 2.71(9) Å (W4), respectively. The Ag1 site (with an occupancy lower than Ag2) is coordinated by the water mole-cules W2, W5 and W6, and it is located at the center of the A channel, confined by the ten-member rings of tetrahedrons. The Ag3 site is close to M3, lying in the C channel and being coordinated by the water sites W3 and W1. The Ag1 and Ag3 positions are well apart to be simultaneously occupied. The bond distances of the framework tetrahedrons fall in the range of values usual for (Si, Al–O) pairs.

The refined site occupancy factors give rise to a total of 4.72(4) Ag atoms per formula unit vs. 4.86(4) apfu from the chemical analysis, and 16.00(3) wa-ter molecules pfu vs. 18.57(3) H2O pfu from the chemical analysis. The missing 2.50(3) water molecules pfu in our refinement is likely due to the distribution of H2O in some very low occupied sites, which are difficult to be localized using powder XRD data.

15. Kinetics and equilibrium of ion exchange of Ag+ on Na-clinoptilolite (N. Lihareva, L. Dimova, O. Petrov, Y. Tzvetanova)

The present study deals with the silver sorption by Na-clinoptilolite [27, 28, 29, 125]. For studying the kinetics and equilibrium of Ag+ uptake we applied a bath sorption procedure (Fig. 1). The kinetic sorption data are analyzed using both pseudo first-order and pseudo second-order models (Table 1). It was found that the pseudo second-order model provides the most appropriate description of

Fig. 1. Uptake of Ag+ ions by Na+-exchanged clinoptilolite as a function of the contact time (100 mg sample, 20 ml Ag+ solution 50 mg/L and

517 mg/L, pHinit = 4.0, t = 20°C).

Fig. 2. Sorption isotherm of Ag+ ions by Na+-exchanged clinoptilolite (100 mg sample, 20 ml Ag+ solution, pHinit = 4.0, contact time 60 min,

t = 20°C).

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the data for both studied initial concentrations of 50 and 517 mg/L. The respective apparent pseudo second-order rate constants k2 are calculated to be 5.12 and 1.07 g/(meq min). The equilibrium data (Fig. 2) fit well to the Langmuir isotherms model, from which, the maximum uptake of Ag+ is estimated to be qm,calc = 234.28 meq/g (Table 2). The Freundlich model was found to be less appropriate.

The theoretical cation-exchange capacity (TEC), based on the content of Na+ in modified clinoptilolite, was 1.72 meq/g. The maximum exchange level (MEL) of Na+-exchanged clinoptilolite for sorption of Ag+, measured by repeated bath ion-exchange experiments, was 1.43 meq/g, or 83.1% of the calculated TEC, due to failure of complete replacement of Na+ ions for Ag+.

16. Binary cation exchange in clinoptilolite, involving K+, Na+, Ba2+ and Ca2+: A calorimetric study at 30 and 95°C (N. Petrova, l. Filizova, G. Kirov)

The ion-exchange properties of zeolite minerals are basis for their applica-tions in water purification, selective sorption and nuclear waste repository. More-over, the ion-exchange approach is used for modifying the catalytic and molecule sieve properties of zeolites.

A binary ion-exchange of cationic pairs involving K, Na, Ba, and Ca in clinoptilolite (Beli Plast deposit) was investigated calorimetrically [48, 94, 138]. The selected cations included two pairs equal in charge and two pairs similar in size. The heat of ion exchange and the degree of exchange were determined at 30 and 95°C. The obtained data are discussed in respect to cationic interactions

Table 1. Kinetic parameters for the Ag+-uptake by Na+- exchanged clinoptilolite – pseudo second-order rate model

Table 2. Langmuir isotherm equations and parameters for the sorption of Ag+ by Na+-exchanged clinoptilolite

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in the clinoptilolite structure and to hydration characteristics (heats of hydration and hydration numbers) of competing cations in the solution. No correlation was found between the heat effects and the degree of exchange.

Fig. 1 presents dependences of the heat of ion-exchange (Q) at 30°C on the differences of the hydration heat of corresponding cations (ΔHh = Hhout – Hhin). The general tendency is that the heats of ion exchange are proportional to the differences of hydration heats of the cation in zeolite (outgoing cation) and replacing (ingoing) cation. Reactions in which the hydration heat of the outgoing cation (Hhout) is higher than that of the cation in solution (ingoing cation, Hhin) are exothermic, whereas they are endothermic in the opposite case. Reaction pairs with the same cations are distributed symmetrically on the graph, for example

Fig. 1. Dependences of the heat of ion-exchange (Q) at 30°C on differences of the hydration heat of corresponding cations (ΔHh = Hhout – Hhin), degree of exchange: 0.9-0.6;

0.6-0.3; up to 0.3.

Fig. 2. Degree of exchange (x) at 30°C (grey) and 95°C (black) with different cation pairs.

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Caout – Kin exchange is the most exothermic, whereas Kout – Cain is the most endo-thermic reaction. The heats of ion exchange are lower at 95°C than at 30°C due to decrease of the hydration number with increasing temperature.

In all cases the degree of exchange increases with increasing tempera-ture. The degree of exchange depends mainly on the cation interactions in the structure, especially on the positional selectivity of competing cations. The degree of exchange was highest when Na+ was used as outgoing cation and decreased according the sequence Na > Ca > K > Ba (Fig. 2). At the same time, the sequence of ingoing cations was K > Ba > Ca > Na. Generally, the most active and strongly bonded with the framework are the exchanging cations with preferences to the channel C (K+ and Ba2+ ), followed by Ca2+ in channel B and Na+ in the 10-member channel A. The same is the sequence of decrease of framework oxygen atoms as well as in the increase of water molecules in the cation surrounding.

17. Tribochemical activation of natural or NH4+-exchanged clinoptilolite

mixed with natural apatite for environmental applications (V. Petkova, N. Petrova)

The tribochemical activation of natural phosphate-clinoptilolite mixtures is a solution of ecological and stuff problems aiming to attain high degree of transition of nonassimilable P2O5 into assimilable by plants form.

Three mixtures with different mass ratio of natural clinoptilolite (Nat-Cpt) and NH4-clinoptilolite (NH4-Cpt) to Tunisian apatite (Ap), namely 80:20, 50:50 and 20:80, were treated by tribochemical activation (TCA) and tribochemical mixing (TCM).

The TCA was carried out in a planetary mill (Pulverisette–5, Fritsch Co, Ger-many) with agate milling bodies while TCM – in an agate mortar.

The obtained samples were blended in 2% citric-acid solution as the variation of phosphate solubility was estimated by the phosphorus content in the solution using a standardized method. Application of thermal methods in complex with IR spectroscopy and XRD allows the study of structural and phase transformations in the system with a focus on changes that occur during tribochemical activation [49, 92, 133, 139].

Thermal behavior: TG and DTG curves of TCM and TCA NH4-Cpt and Ap are presented on Fig. 1. Variety of events is manifested in different manner depending on treating and mixing procedure and the cation composition in clinop-tilolite: related both to the zeolite structure – stages of dehydration and deamoni-tages of dehydration and deamoni- and deamoni-eamoni-

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zation and to the apatite structure - decarbonization of the products of izomorphic substitution in apatite structure (A-type carbonate-Ap, B-type carbonate-Ap, and calcite), decomposition of OH-F-Ap and formation of tetracalcium phosphate.

Chemical results for P2O5ass were cal-were cal-

culated per total amount of P2O5. Depend- Depend-ences of P2O5

ass/P2O5total on Nat- and NH4-

Cpt content in the mixture are presented on Fig. 2. Almost 100% assimilation of P2O5 was obtained in the case of 80% content of NH4-Cpt when TCM was used whereas TCA stimulates the solubility when the phosphate part dominates in the mixture. Explanation of these results is different in different cases of mixing and treating:

Fig. 1. TG-DTG curves of samples treated by TCM (a) and TCA (b).

Fig. 2. P2O5ass/P2O5 total relations vs Cpt

content in the mixtures.

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(i) The TCM tolerates ion-exchange reactions in the systems: Soil solution

Ap + NH4+ (K+, Na+)-Cpt ↔ Ca-Cpt + NH4

+ (K+, Na+)sol + (H2PO4)–

sol

(ii) The effect of ion- exchange reaction is manifested in great manner when NH4-Cpt dominates. NH4-Cpt or K-Na (Nat) Cpt acts as a sink for Ca2+ during exchange, thereby releasing NH4

+ (K+, Na+) , and lowering the activity of Ca2+ in the solution.

Fig. 3. IR spectra of the activated Nat- and NH4-Cpt and the mixture of 80:20.

Fig. 4. XRD data of activated Ap.

(iii) The TCA leads to deformation and rapture of Si-O-Si and Si-O-Al bonds (Fig. 3) and decreasing of ion-exchange ability. At the same time the activation provokes the amorphization and structural defectiveness in apatite structure (Fig. 4), which leads to increase of the reaction ability especially in the case of apatite domination.

18. Energetic aspects of volcanic ash-water interaction and zeolitiza-tion of volcanic ash rocks (G. Kirov, N. Petrova)

The volcanic ash ejected in the atmosphere is disseminated as pyroclastic flows, ash clouds, ash falls, and emplaced pyroclastic deposits both on dry land and in water basins. All significant zeolite deposits are related to alteration of volcanic glass, which is the main part of the volcanic ash. Ash depositions, which-ever way transported are zeolitizited and clinoptilolite dominates in tuffs formed from rhyolitic tephra while phillipsite – in basaltic ones.

Three series of experiments with different ash/water mass ratio and ash temperature of 500°C were performed [22, 120]. The temperature of the hot ash

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deposit was measured on six levels in the column. The change of temperature profiles of the deposit in one of the experiments is shown on Fig. 1. Calculated temperatures in the system at different ash/water ratios and temperatures of 300, 500, and 800°C of the ash immediately after emplacement are summa-rized in Table 1.

It was established that the main factors determining the temperature of the ash deposit are both the temperature of ash flow and the ash/water mass ratio. The dependence on ash/water ratio determines the observed temperature zon-ing in ash deposition, which is characterized by the coldest bottom layer and the hottest top one. In case of such temperature profile of the deposition no convec-tion of the pore solution from bottom to upper layers is possible to occur, while an active convective heat transport is observed from hottest layers to water surface.

Fig. 1. Change of temperature profiles of the ash-water system in the case of partially ash-filled

column.

Table 1. Temperatures of homogenous ash-water systems (°С) in closed basin at initial water temperature of 20°С and ash temperatures of 300, 500, and 800°C.

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Substantial heat transfer to coldest bottom layers of the deposit was not found. Significant water evaporation during hot ash entrance into the water was estab-lished even at low ash/water ratio, whereas more than half of the heat energy entering by the hot ash is spent for water evaporation at high ash/water ratio.

The observed thermal water-to-ash relations are predetermined by high heat capacity (4.2 Jg–1K–1), large heat of evaporation (2260 Jg–1) and low boiling temperature of water (100°С), on one hand, and the low heat capacity of volcanic glass (0.88 Jg–1K–1), on the other hand. The maximum of the possible tempera-ture in the system is 100°C and due to both active heat export and heat exchange between marine basin and ash deposit the cooling of the deposition is a fast process. The above excludes the possibility for origination of the hydrothermal systems at the expense of residual heat of the volcanic ash during its deposition into a water basin. If such kind of system is possible, then the high temperature zeolite association would be firstly expected to form.

4.6. Synthesis, composition, structure, and properties of minerals and new materials

19. Growth of Mixed Alkaline-Earth Fluorides for Laser Host Applica-tions (J. Mouchovski)

A comprehensive analysis is implemented concerning the growth, prop-erties, and applications of doped – co-doped single and mixed alkaline-earth fluoride systems [44]. Calcium strontium fluoride solid solutions with Sr content proportion varying widely between 0.007 and 0.675 mol.% are obtained as a batch of axis-symmetrical boules grown by a Bridgman-Stockbarger method. The crystallization front (CF) can be controlled to retain a convex CF-shape that is favourable for normal growth of single crystals. This was achieved using a broad adiabatic furnace zone independently of the boules’ composition. The influence of thermal field distribution on the CF and the real crystallization rate, which are both critically decisive in controlling crystal quality, were originally assessed us-ing empirically derived formulas. The optical characteristics of the grown boules were monitored by measuring the external transmittance t and calculating the total losses following light irradiation of optical windows that were prepared from sections of the boules that had been cut parallel to one another. The t-measure-ments were performed by two different techniques and the comparative analysis of the results reliably indicates of any inhomogeneity in the grown boules. A sim-ple suppercooling criterion proved to closely relate to the morphological stability

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of the CF enabling one to set up the optimum growth conditions. Thus, the normal growth criterion outlines the concentration bounds where the isotropic growth mechanism is replaced by cellular anisotropic growth.

A procedure has been established for provisioning researchers with optical quality calcium strontium fluoride crystals with widely varying composition grown under practically identical conditions. As a consequence, one can explore pos-sible reasons that can affect the growth mechanism for this or any other systems with a fluoride structure and so provide scope aimed at the future improvement of the crystal quality, thereby enlarging the field of mixed fluoride systems’ ap-plications.

20. Quantitative analysis of garnet solid solutions from skarn zones using Rietveld-based XRD method (Y. Tzvetanova, O. Petrov)

The relative quantity of the constituent minerals in a sample of rock is not only important for classification and to determine paragenesis, but is also es-sential for characterization, economic extraction, and concentration of potentially valuable minerals.

All studied samples originated from the zonal calcic skarns included in mon-zonites from Zvezdel pluton, Eastern Rhodopes. Five samples from garnet and

Fig. 1. Crucial melt temperature gradient, Gcrit, for Ca1-xSrxF2 crystal solid solutions grown simultane-ously at different temperature regimes and crystallization rate equal to: 6 mm/h (£), 3 mm/h (▲), 2.5 mm/h (r), 2 mm/h (�) and 1 mm/h (�). By straight lines are shown: 1) the maximum axial tempera-ture gradient along the AdZ measured using an empty fixed crucible: run 1 – G1e; run 2 – G2e. 2) maxi-

mum melt temperature gradient before CF, calculated dividing G1/2e by factor of 2.8.

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garnet-pyroxene zones were analyzed with the Rietveld method (FullProf Suite Program 2009). Step-scan X-ray powder diffraction data were collected over a range of 4–80 2θ with CuKα radiation on D2 Phaser – Bruker AXS Bragg-Bren-tano diffractometer operated at 30 kV and 10 mA with a step size of 0.02 2θ and a counting time of 4 s/step [157].

Minerals identified in thin section include quartz, calcite, garnets (two gen-erations – small-sized garnets and coarse-grained garnets), pyroxenes, prehnite, secondary chlorite, and accessory minerals – apatite, titanite, magnetite. The X-ray Rietveld refinement incorporate only five phases: quartz, calcite, two gar-nets, pyroxene, and chlorite; the other minor phases could not be detected above background. Starting values for the atomic positions and cell dimensions for each phase were obtained from published crystal-structure refinements of minerals with compositions similar to those in the studied samples. The compositions of selected individual phases were determined by electron-probe microanalysis. The obtained data were used to assist with precise mineral identification and to compare with the XRD-derived mineral compositions.

Refinements for quantitative phase-analysis were done in the following general sequence: zero-shift parameter, sample displacement parameter, scale factors for all phases, background polynomial parameters, unit cell dimensions of the phases, asymmetry parameters, and preferred orientation parameters for

Fig. 1. Rietveld refinement plots for garnet-pyroxene skarn. The rows of vertical lines give the positions of all possible Bragg reflections for (from top to bottom) quartz, calcite, grossular,

andradite, chlorite, diopside.

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phases with marked grain-shape anisotropy. Phases in concentrations greater than about 25% were refined further for site occupancies and overall temperature factor alternatively, depending on the composition of the sample [157].

Plots of the observed, calculated, and ‘difference’ powder diffraction pattern profiles for the Rietveld refinements of selected sample are given in Fig. 1. The fit between the calculated and observed diffraction profiles obtained in a Rietveld refinement is usually expressed in terms of the standard agreement indices Rp, Rwp, Rexp, GofF and DW-Stat. These indices are a measure of the fit between the observed and calculated profile at each step in the pattern. For the sample shown in Figure 1 the indices are: Rp – 10.4, Rwp – 13.8, Rexp – 8.61, GofF – 1.6 and DW-Stat. – 1.14.

Determination of mineral abundance by the Rietveld refinement for the selected sample is: quartz – 2.64(0.06) wt.%, calcite – 5.60(0.17) wt.%, gros-sulare (~70% Ca3Al2Si3O12) – 21.41(0.35) wt.%, grossular-andradite (46–54% Ca3Fe2Si3O12) – 12.82(0.31) wt.%, pyroxene (60 wt.% diopdise component) – 57.52(1.17), and chlorite ~ 0.2 wt.%.

The results were compared to those obtained by optical modes point count-ing of minerals in thin section using an optical microscope. The determinations of mineral quantities by the two methods are in good agreement.

21. New data on the crystal chemistry of nano-sized microporous ti-tanosilicates with pharmacosiderite structure (V. Kostov-Kytin, R. Nikolova, N. Nakayama, S. Simova, P. Tzvetkova, R. Titorenkova, N. Petrova, V. Ganev)

Previously synthesized pure Na or K and mixed (Na, K) nano-sized GTS ma-terials have been thoroughly characterized by powder XRD, EPMA, ICP-OES, LA-ICP-MS, DTA-TG, HR TEM, IR, Raman, and 29Si MAS-NMR methods in order to elucidate the problem of excess of Si vs. deficiency of Ti in the obtained phases and to characterize the type and amounts of the present water [13, 122, 154]. Chemical analyses established increasing Si/Ti ratios towards the potassium end-member. No traces of amorphous material or other phases were detected among the run-products by the rest of the applied for characterization methods. Based on the 29Si MAS-NMR spectroscopy data (Fig. 1.) a structural model is proposed for the as-synthesized materials illustrating the deficiency of Ti in the framework of all phases being located towards the crystallites periphery (Fig. 2.).

Fig. 2a depicts typical silicon environment as derived from the ideal for-mula of this compound. We assign the main intense signals at –85.5 and –88.5

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ppm for the Na-containing (Na-GTS-100, NaK-GTS-200) and the pure K-samples (K-GTS-200), respectively as being due to the bulk SiO4 tetrahedra inside the crystallites. Fig. 2b illustrates the presence of proton(s) in the Si environment compensating either the repulsion of the alkaline metals or their deficiency. The chemical shift of such structure type should not differ substantially from the main one. Fig. 2c depicts silicon environment with titanium deficiency. We assign the low intensity signals at –78.5 ppm (Na-containing forms) and –79.5 ppm (K-form) as being due to such framework imperfection.

The smallest in size grains of the pure K-form are mostly affected by the tita-nium shortage. Similarly to the pore size and degree of crystallinity, the controlled through the synthesis conditions surface Ti deficiency appears to be a key-factor for the acid-base properties of such materials achieving optimization of the ad-sorption capacity and rapid uptake of large cations such as Cs+ and Sr2+.

The amount of total water release decreases from Na to K end-member, which is evi-denced by DTA-TG data that show overlapping effects due to multistage water release. However, the water molecules are stronger bonded to the framework in K end-member,

which is also confirmed by vibrational spectra [154]. A systematic change of ab-sorption spectral features from Na to K end-member is observed, namely fre-quency shift, broadening and appearing of additional peaks. These spectral pe-culiarities indicate an increase of bond length distribution and higher degree of framework defects for K end-member.

Fig. 1. 29Si MAS-NMR spectra (6kHz) of pharmacosiderite-type titanosilicate samples. Single pulse – solid lines, cross-polarization – dashed lines.

Fig. 2. Three Si species within the Ti deficient frameworks of the studied pharmacosiderite-type titanosilicates.

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22. Attenuated total-reflection infrared microspectroscopy of partially disordered zircon (R. Titorenkova, B. Gasharova, B. Mihailova, L. Kon-stantinov)

Polarized synchrotron-based attenuated total-reflection infrared (ATR–IR) spectra of crystals of natural zircon of various origins and degree of disorder are reported. We demonstrate the potential of ATR–IR microspectroscopy for non-destructive structural analysis of zircon microcrystals. Disorder-related IR absorption at wavenumbers lower than the bands arising from the fundamental A2u[ν3(SiO4)] and Eu[ν3(SiO4)] zircon modes was observed, which reveals the ex-istence of spatial regions with abundant SiO4 tetrahedra with longer bonds. A pro-nounced peak near 990 cm–1 is indicative of an abundance of polymerized SiO4 tetrahedra. Weak signals in the range 1050–1250 cm–1 show connectivity defects (broken Si–O–Zr bridges) and the existence of shorter Si–O bonds [65].

23. TEM study of nanosized Al2(WO4)3 (D. Nihtianova, N. Velichkova, R. Petrova, I. Koseva, A. Yordanova, V. Nikolov)

Aluminum tungstate, Cr:Al2(WO4)3, doped by Cr, is a promising material for tunable laser applications. It belongs to the materials with a low coefficient of thermal expansion, so a special ceramic could be produced. Finally, Al2(WO4)3 possesses a high level of Al3+ conductivity. Nanosized aluminum tungstate, Al2(WO4)3, is prepared by a precipitation reaction between Na2WO4 and Al(NO3)3. Initial product is amorphous and composes of 20–25 nm-sized, well defined particles. This amorphous product converts into crystalline one after 5 hours heating at 630°C.

Fig. 1. a) Fourier filtered HRTEM image of Al2(WO4)3 sample along [012] orientation; b) Enlarged part of the same image.

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The structure of the precipitated composition is determined by TEM (SAED, HRTEM).

TEM investigations are performed by a standard procedure with electron mi-croscope JEOL 2100 at an accelerating voltage 200 kV. Several crystallographic sections are obtained by SAED for Al2(WO4)3 PDF 81-2415: [010], [012], [021], [211] and [112]. Al2(WO4)3 is a main phase for the crystalline product, but some impurities of W5O14 PDF 71-0292 are observed in orientation [001]. The experi-mental SAED patterns are compared with calculated ones and a good agreement is observed.

Several HRTEM images are obtained for revealing some details of the microstructure at an unit cell level: in orientations [010], [012] for Al2(WO4)3 and in [001] for W5O14.

24. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites (V. Lilkov, O. Petrov, V. Petkova, N. Petrova, Y. Tzvetanova)

Results are presented from comparative thermogravimetric, calorimetric and pozzolanic activity analyses of five natural zeolite samples from Bulgaria,

Fig. 1. Powder XRD patterns (1 year of hydration) of cement with addition (10, 20, and 30%) of mordenite (a) and clinoptilolite from Beli plast (b), Slovakia (c) and New Mexico (d).

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Slovakia, Philippines, USA and North Korea [31, 86, 127]. The used zeolites ac-tively participate in the hydration processes of cement. Their activity in the early stage of hydration is based mainly on the well developed specific surface of the separate particles, while in the later stages activation of the chemical reactions occurs between the products of hydration of cement and the soluble silicon diox-ide that is present in the composition of the zeolites studied. It was proved that in all cement pastes with zeolite addition the quantity of portlandite is lower than that in the pure cement paste or is even totally absent (Fig. 1).

The amount of hydration products is greater in the compositions with 30% zeolite than in those with 10% zeolite (excluding the sample with chabazite). Lowest pozzolanic activity is shown by chabazite, which possesses the lowest SiO2/Al2O3 ratio.

25. Rheological, porosimetric, and SEM studies of cements with addi-tions of natural zeolites (V. Lilkov, O. Petrov, Y. Tzvetanova)

Rheological, porosimetric, and SEM studies of cements with additions of natural zeolites (chabazite, mordenite, and clinoptilolite) were investigated [32, 87, 128]. The addition of 5% zeolite to cement pastes had a plastifying effect. The increase in the rheological parameters of aqueous cement-zeolite suspen-sions began after additions of more than 10% zeolite. At a water/solid ratio (w/s) =0.5 all compositions exhibited similar rheological behavior for yield stress and maximum shear stress values. At lower w/s values the rheology depended on the zeolite used, decreasing in the order Sl (clinoptilolite, Nižny Hrabovec deposit, Slovakia), M (mordenite, Phillipines), Bp (clinoptilolite, Beli Plast deposit, Bul-garia), NM (clinoptilolite, Saint Cloud deposit, New Mexico) and Ch (chabazite, Nam Yan deposit, Korea).

After 28 days of hydration, the mixtures containing 10% Bp clinoptilolite, mordenite, and Sl clinoptilolite (up to 30%) had unchanged specific pore vol-umes, but additions of 10% and 30% of chabazite and NM clinoptilolite and of 30% mordenite and Bp clinoptilolite lead to increases in the total specific pore volume compared to the neat cement paste.

Between the 28th and 180th day of hydration, the specific volume of the pores in all the cement-zeolite pastes decreased due to the filling of the pores with products from the pozzolanic reaction between the zeolites and the hydration products of cement (Fig. 1).

The pozzolanic reaction between zeolite and the hydration products of ce-ment is enhanced by the zeolite content in the samples; the Si/Al ratio – more

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siliceous zeolites are clinoptilolite (Si/Al>4.50) and mordenite (Si/Al>5) than chabazite (Si/Al<2.5); and the surface area (clinoptilolite from Slovakia is with smallest crystallites giving greater reactive surface area).

26. New equipment in the laboratory “X-ray diffraction structural analy-sis” – IMC-BAS (R. Nikolova, O. Petrov, B. Mihailova, Y. Kalvachev, V. Kostov, B. Shivachev, M. Kadiyski, M. Gospodinov, T. Milenov, P. Rafailov, G. Avdeev, T. Spassov, G. Gencheva, V. Ilieva, P. Gorolomova, V. Kurteva, K. Kostova)

In July, 2010, the renewed laboratory “X-ray diffraction structural analy-sis” in the Institute of Mineralogy and Crystallography “Acad. Ivan Kostov” start-ed an effective functioning. The acquisition of new equipment was in the frame of the project “Structural characteristics of new crystalline materials” – DRNF 02/01 of the Bulgarian National Science Fund targeting the improvement of the quality of the performed structural studies and the education of young researchers. The needed equipment for performing modern scientific and applied studies has been ensured: a single crystal X-ray diffractometer Supernova, Oxford Difraction (Fig. 1) has been purchased, which is supplied with two X-ray sources, CCD detector, micro-focus optics, and low/high temperature attachment “Cobra” (from –200 to +130°C) of Oxford Instruments, DLS particle size analyzer (<1–6000 nm), 90Plus,

Fig. 1. SEM micrographs of the cement pastes with zeolites after 6 months of hydration: clinoptilolite particle (Slovakia) (a, b) and its contact zone with the cement paste (c); the hydrate products on the contact surface of clinoptilolite crystals (Beli Plast deposit) with the cement paste (d); the hydrate

products of cement crystallized on the crystals of chabazite (e, f).

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Brookhaven Instruments (Fig. 2), digital microscope Motic SMZ-168, multifunc-tional nitrogen generator, crystallographic databases containing more than 800 000 compounds: Cambridge Structural Database – CSD, International Centre for Diffraction Data – ICDD, Inorganic Crystal Structure Database – ICSD.

The main task of the laboratory is to characterize crystalline compounds: minerals, small organic molecules as well as structure determination of proteins and DNA complexes. The collaboration of four scientific organizations guaran-tees the quality of education and is a basis for successful work on various state of the art scientific problems ensuring complex development and training of young scientific workers [2, 105, 108, 110, 111, 112, 113, 124, 147].

The studied single crystals are distributed amongst the members of the con-sortium as follows:

– Institute of Mineralogy and Crystallography “Acad. Ivan Kostov” – samples of natural and Zn-exchanged clinoptilolite, phenyl-boronic acids and condensed phenyl-boronic acids; single crystals of two proteins were success-fully grown. In collaboration were obtained and structurally studied products, which are derivatives of efedrine with potential pain suppressing properties. The structures of 27 new compounds were determined.

– Institute of Solid State Physics – syntheses are performed for prepara-tion of new substances in the systems Bi-Co(Ni)-Mn(Ru)-O and Fe-Li-O. The structures of 3 new compounds were solved.

– Institute of Organic Chemistry with Centre of Phytochemistry – syn-thesized are two new compounds and their structures were determined.

Fig. 1. Single crystal diffractometer Supernova. Fig. 2. Analyzer of particle size.

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– Chemical Faculty of Sofia University – new stilbene derivatives were synthesized and for part of them there were obtained single crystals suitable for analysis. The structural studies will be performed during the second stage of the project. There were also synthesized Cu and Mn metalloorganic compounds of the type MOFs (Microporous Metal Organic Frameworks) with various organic ligands. The crystal structures of 18 new compounds were determined.

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5. Monographs

A book about the natural treasures of Bulgaria1

The monographic issues in the field of geological sciences are generally a rare event in Bulgaria. But it becomes especially remarkable when before the scientific community and the general readership is presented such a work as the present, the result of many years of research efforts.

Agates, these phenomenal natural polymineral formations, excite the sens-es and perceptions of people throughout the centuries of human civilization. They are incredibly beautiful, and infinitely varied, and extremely resistant, and provok-ing the imagination of scientists, aesthetes and masters of jewellery – just an enigmatic and challenging natural microworld.

On this background, the most striking is that the geological sciences, and particularly mineralogy, are still in debt to the agates. Yes, their deposits and oc-currences, their structural features and microfabrics, their colors, tints, shades and fantastic shapes have been described and documented hundreds of times. But, is it enough to say, for example, that agates are built mainly of different varie-ties of SiO2 (as stated in the most published specialized studies so far)? So, only the approved by the International Mineralogical Association mineral species and varieties of SiO2 are more than 10. Adding ambiguous terms received small or large popularity in the literature and applied vocabulary, the degree of scientific uncertainty to the terminology, composition and structures of agates at the begin-ning of the XXI century is too high and completely unacceptable.

In this sense, the monograph “Agates in Bulgaria” by Z. Tsintsov and B. Banu-shev is generally among the first scientific works, which provides detailed minera-logical diagnostics and characterization of species and varieties of SiO2, composing the agates studied. The authors of this work are practically among the first Bulgar-ian scientists started and carrying out more than 35 years specialized systematic studies of agates in the country. After a series of publications in international and national journals in recent decades, their long-standing research on the Bulgarian agates found its logical end in the present monographic issue.

The monograph presents the main results from a undoubtedly topical, tar-geted, systematic and thorough study of over 70 agate occurrences, known in Bulgaria, with significant basic and applied contributions. Using a well-chosen

1 Tsintsov, Z., B. Banushev. 2010. Agates in Bulgaria. Vanyo Nedkov Publ. House, Sofia, 210 pp., ISBN 978-954-9462-46-3 (in Bulgarian).

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modern set of diagnostic methods and analytical techniques and based on the official terminological nomenclature of the SiO2 phases, the authors carried out a systematic study on the composition, morphology, structures, mineral associa-tions and host rocks of the numerous agate occurrences in the country.

The main geological features of the regions with agate occurrences are pre-sented in summary. They include the eastern parts of the Moesian Platform, the Sredna Gora and the East Rhodope volcanic regions which are geographically distinguished into 9 agate districts. The geological settings, spatial distribution and petrographic characteristics of the host rocks are described for each one of the districts. The agate occurrences are examined in detail mineralogically and petrographically by both field observations and laboratory studies. It was found and documented a great variety of two morphological-genetic types of agates, geodes and veined, as regards the composition, size, shape, color, inclusions, structural features and fabrics, and associated minerals. Based on the analysis of the obtained data, it is discussed a wide range of genetic questions. The authors’ viewpoint on the origin of various agate types and the mechanisms of formation of a number of their specific features is presented.

In this book the reader will find answers to many questions, some of which the authors ask in the preface: What are agates, what is their composition, where

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and how they occur in Bulgaria, etc. But as in any scientific work, especially in the field of earth sciences, still remain open questions related to the conditions and mechanisms of formation of various types of agates, factors determining their varied colors, zonal structure and phase inhomogeneity, etc. Because in the geological sciences research simply can not have a final end, but only completion of a certain stage...

The monograph is richly illustrated with both numerous macro- and micro-photographs of unique agate specimens and a large number of data and results from analytical studies, diagrams, geological maps and more. Thus, apart from new knowledge and undoubtedly aesthetic enjoyment for the readers, it can be used also for future comparative research, and even as a kind of “guidance” for accurate mineralogical-petrological studies from students, young scientists, and professionals.

After familiarization with the huge factual and illustrative material presented in the monograph, the readers will undoubtedly be enriched both as professionals and as aesthetes - admirers of natural beauty and mystery.

Moreover, in all cases this is not a book for “single” use – to read it, to en-large your knowledge and to forget it. After years each one would find in it some-thing new, previously unnoticed, surprising and useful...

Z. Damyanov

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6. International Cooperation

“Safety evaluation of manufactured nanomaterials by characterization ●of their potential genotoxic hazard” (NANOGENOTOX) – a joint research project between IMC and 15 organizations (governmental and scientific institutions) from 10 EU member states, funded by the Executive Agency for Health and Consumers (EAHC) under the European Commission’s Health Programme and coordinated by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES).

● “Following the tracks of metallurgy of Ancient Thracia” – a joint research project between IMC and the National Institute of Archaeology and Museum – BAS (principle organization) and the University of Munster, Germany, funded by the Alexander von Humboldt Foundation.

“Synthesis of new inorganic ionites (titanosilicates and zirconium ●dioxide) and investigation of their efficiency for removing long-term radionuclides (as Cs, Sr) as well as toxic anions in waters and waste waters” – a joint research project between IMC and the Institute of Sorption and Problems of Endoecology, National Academy of Sciences of Ukraine, funded by the Bulgarian National Science Fund.

● “Synthesis and crystal-chemical study of porous materials – potential catalysts, sorbents and biologically active materials” – a joint research project between IMC and the Institute of Inorganic Chemistry, Chezh Academy of Sciences, under the bilateral academic agreement with equivalent non-currency exchange.

● “Preparation of organo-mineral composites for soil amendment” – a joint research project between IMC and the Tallinn Technical University and the Estonian Academy of Sciences, under the bilateral academic agreement with equivalent non-currency exchange.

● “Minerals of rare elements in granites of S- and A-types on the example of peraluminous granites of Bulgaria and alkaline granites of the Kola Peninsula, Russia” – a joint research project between IMC and the Geological Institute of the Kola Science Centre of the RAS, under the bilateral academic agreement with equivalent non-currency exchange.

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7. Visiting Scientists

D.Sc. Stanislav Vassilev – National Expert of Bulgaria in the Joint Research Center of the European Commission, Institute for Energy, Petten site, The Netherlands

Dr. Boriana Mihailova – visitor-professor on “Spectroscopy of minerals” and “Crystal Physics” at the Faculty of Earth Sciences, University of Hamburg, Germany

Dr. Stanislav Ferdov – Department of Physics, University of Minho, Guima-raes, Portugal

8. Research Topics, Announced for International Partnership Collaboration

Advanced multicomponent utilization of fly ashes from European coal-fired power stationsOne of the environmental problems in Europe is the utilization of fly ashes

(FAs) from coal-fired thermoelectric power stations (TPSs). This potential investi-gation will include characterization of various products recovered from FAs at Eu-ropean TPSs in an attempt for multicomponent FA utilization (MFAU). The MFAU is a necessary and unavoidable process due to the complex, heterogeneous and unique polycomponent composition of FA. The purpose will be: (i) to demon-strate how a low-cost waste can be transformed into useful, high-grade and valu-able materials, which may find various applications; (ii) to provide a basis for the advanced, multicomponent, wasteless and environmentally friendly utilization of various FAs. The knowledge about the composition of FAs is sufficient to start an advanced and effective MFAU.

Structure and properties of new multifunctional materialsSynthesis and investigation of new materials of practical importance (nano-

sized zeolite-type natural and synthetic materials and thin films; ferric iron oxide materials; catalysts based on micro- and mesoporous carriers for removal of soot and nitrogen oxides from exhausted gasses; titanosilicate porous materials for ion-exchange, sorbents, and catalytic systems; materials for optical and mag-netic storage and processing of information; preparation and investigation of coal char based sorbents and catalysts). Characterization methods: X-ray diffraction, electron microscopy, Raman scattering and infrared absorption spectroscopies, optical measurements and chemical analysis. Education: M.Sc. and PhD in Min-eralogy and Crystallography and Material Sciences.

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9. Publications and Reports at Scientific Forums9.1. Published Articles and Reports

Angelova, S. E., P. Y. Petrov, M. P. Stoyanova, 1. R. P. Nikolova, B. L. Shivachev. 2010. Synthesis of 1,2,3,4-substituted spiroheterocyclic tetrahydroisoquinoline-1-ones and their structural similarity in water solution and in crystallohydrate solid state. – Arkivoc (ii), 303–314, ISSN 1551-7012.Apostolova, M.D., 2. R.P. Nikolova, B.L. Shivachev. 2010. (4-Carbamoylphen-yl) boronic acid. – Acta Crystallographica, Section E, 66 (6), pp. o1273.Beirau, T., U. Bismayer, 3. B. Mihailova, C. Paulmann, L. Groat. 2010. Structural phenomena of metamict titanite: a synchrotron x-ray diffraction and vibrational spectroscopic study. – Phase Transitions, 83, 694–702. Chepurna, I., V. Kanibolotskyy, V. Strelko, S. Prudius, S. Meleshevych, 4. Yu. Kalvachev. 2010. Mesoporous Spherically Granulated Sulfated Zirconium Dioxide Synthesized by Sol-Gel Method. – Topics in Chemistry and Material Science, Vol. 4, Advanced Micro- and Mesoporous Materials – 09 (Eds. K. Hadjiivanov, V. Valtchev, S. Mintova, G. Vayssilov), 94-105, ISSN 1314-0795.Dimitrov, L.5. , R. Palcheva, A. Spojakina, K. Jiratova. 2010. Synthesis and characterization of W-SBA-15 and W-HMS as supports for HDS.– J. Porous Mater., DOI 10.1007/s10934-010-9394-0.Dimova L., O. Petrov, N. Liharevа6. , A. Stoyanova-Ivanova, V. Mikli. 2010. Preparation and characterization of Ag-exchanged clinoptilolite (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 84-85. .Dimova, L.,7. G. Kirov, A. Stoyanova-Ivanova, V. Mikli. 2010. EDS and XRD study of ZnCl2 occluded clinoptilolite (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 82–83. Dul’kin, E., 8. B. Mihailova, M. Catalan, M. Gospodinov, M. Roth. 2010. Phase transformation above Tm in PbSc0.5Ta0.5O3 relaxor as seen via acoustic emission. – Phys. Rev. B, 82, 180101(R).Dul’kin, E., 9. B. Mihailova, M. Gospodinov, M.E. Mojaev, M. Roth. 2010. Evidence of local anisotropic strains in relaxor ferroelectrics below the intermediate temperature T* detected by acoustic emission. – J. Phys.: Condens. Matter, 22, 222201/1-4. (included in the 2010 IOP collection comprising articles chosen for their novelty, significance and potential impact on future research)Ferdov, S10. . 2010. Temperature- and Vacuum-Induced Framework Contraction of Na-ETS-4. – Langmuir, 26 (4), 2684–2687.Ferdov, S.11. , P. Rauwel, Z. Lin, R.A. Sá Ferreira, A. Lopes, A. 2010. A simple and general route for the preparation of pure and high crystalline nanosized lanthanide silicates with the structure of apatite at low temperature. – Journal of Solid State Chemistry, 183 (11), 2726–2730.Ferdov, S12. ., Z. Lin. 2010. Selective Detection of Cs+ in Water Solutions via One-Step Formation of a New Type of Struvite-Like Phosphate. – Chemistry of Materials, 22 (18), 5345–5349.Fujiwara, K., T. Shiode, H. Sugimoto, A. Nakatsuka, N. Nakayama, 13. R. P. Nikolova, V. Kos tov-Kytin. 2010. Hydration State of GTS-type Titanosilicate (K,Na,H)4Ti4Si3O16.nH2O Fine Particles. – Topics in Chemistry and Material Science, Vol. 4, Advanced Micro- and Mesoporous materials – 09 (Eds. K. Hadjiivanov, V. Valtchev, S. Mintova, G. Vayssilov), pp. 184–190, ISSN 1314-0795.Galuskina, I. O., L. Ottolini, 14. M. Kadiyski, Th. Armbruster, E. V. Galuskin, P. Dzierzanowski, A. Winiarski. 2010. Pertsevite-(OH), a new mineral in the pertsevite series, Mg2(BO3)1–x (SiO4)x(F,OH)1–x (x < 0.5), from the Snezhnoye deposit in Sakha-Yakutia Republic, Russia. – American Mineralogist, 95, 953–958.Ivanov, V., 15. M. Tarassov, R. Ruseva, V. Petrova-Tacheva, I. Mindov. 2009. II. Electron microscopy investigation of lyophilised blood serum used like an absorbent for gas masks. – Ecology and Future [Ekologiya I badashte], 1, 32–34, ISSN 1312-0751 (in Bulgarian, published in 2010).

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Ivanov, V., 16. M. Tarassov, R. Ruseva, V. Petrova-Tacheva, R. Katsarova. 2009. III. Electron microscopy investigation of lyophilised blood plasma used like an absorbent for gas masks. – Ecology and Future [Ekologiya I badashte], 1, 35–38, ISSN 1312-0751 (in Bulgarian, published in 2010).Ivanov, V., 17. M. Tarassov, R. Ruseva, V. Petrova-Tacheva, S. Dyankova. 2009. I. Electron microscopy investigation of lyophilised erythrocyte mass used like an absorbent for gas masks. – Ecology and Future [Ekologiya I badashte], 1, 29–31, ISSN 1312-0751 (in Bulgarian, published in 2010).Ivanova, P., 18. N. Zidarov. 2010. Spinel accesories in ultramafic and mafic rocks from Gega ophiolite mélange in Ograzhden Mountain, Southestern Bulgaria. – Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9-10, 43-44 (ISSN 1313-2377).Kadiyski, M.19. , Th. Armbruster. 2010. Effect of the type of exchangeable cations on the de-hydration behaviour of heulandite: a comparative X-ray single crystal study (extended ab-stract). - Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 121–122.Kadiyski, M.20. , Th. Armbruster. 2010. Stepwise dehydration of heulandite-Ba: A single crystal X-ray study (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 123–124.Kalvachev, Yu21. . 2010. Dissemination and exploitation of grids in earth science. – Proceedings of 10th International Conference – Modern Management of Mine Producing, Geology and Environmental protection, Albena, Bulgaria, 1111–1119 (ISSN 1314-2704). Kirov, G., 22. N. Petrova. 2010. Energetic aspects of volcanic ash-water interaction and zeolitization of volcanic ash rocks (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 133–134. Kostov, R. I., 23. Y. Tzvetanova, V. Vladimirov. 2010. Petrophysical characteristics and phase composition of zeolitic rocks applied to cultural heritage (Tatul rock sanctuary, Eastern Rhodopes, Bulgaria). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 138–139.Kostov, R. I., 24. Y. Tzvetanova, Y., V. Vladimirov. 2010. Petrophysical and phase composition characteristics of zeolitic rocks applied to cultural heritage (Tatul rock sanctuary, Eastern Rhodopes, Bulgaria). – Geology and Mineral Resources, 10, 21–25.Kostova, B.,25. M. Gospodinov, L. Konstantinov. 2010. Optical absorption of Bi12SiO20:M (M=Cr, P, Cr+P). – 7th International Conference of the Balkan Physical Union, edited by A. Angelopoulos and T. Fildisis 2009, American Institute of Physics Conference Proceedings (AIP CP), 1203, 193-198, ISSN: 0094-243X.Kostov-Kytin, V., N. Lihareva, R. Nikolova26. . 2010. Crystal chemical characterization and sorption ability of nano-sized microporous titanum silicates with pharmacosiderite stucture (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 141–142. Lihareva N., L. Dimova, O. Petrov, Y. Tzvetanova27. . 2010. Kinetics and equilibrium of ion exchange of Ag+ on Na-clinoptilolite. – Bulg. Chem. Commun., 42, (4) 305–311.Lihareva, N., L. Dimova, O. Petrov, Y. Tzvetanova28. , 2010. Kinetics and equilibrium of Ag+ exchange on clinoptilolite (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 162–163. Lihareva, N., L. Dimova, O. Petrov, Y. Tzvetanova29. . 2010. Ag+ sorption on natural and Na-exchanged clinoptilolite from Eastern Rhodopes, Bulgaria. – Micropor. Mesopor. Mater., 130, 32–40.Lilkov, V., I. Rostovsky, 30. O. Petrov. 2010. Physical and mechanical characteristics of cement mortars with addition of clinoptilolite from Beli plast deposit (Bulgaria), silica fume and fly ash: Part 2. SEM and porosimetry examinations (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 170–171.

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Lilkov, V., 31. O. Petrov, V. Petkova, N. Petrova, Y. Tzvetanova. 2010. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 168–169.Lilkov, V., 32. O. Petrov, Y. Tzvetanova. 2010. SEM and porosity studies of cements with additions of natural zeolites (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 166–167. Lilkov, V., 33. O. Petrov, Y. Tzvetanova. 2010. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites.– Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 168–169. Macheva, L., V. Ganev34. . 2010. Fluid enhanced metamorphic transformations of granitoid rocks into orthoschists, East Rhodopes. – Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 29–30 (ISSN 1313-2377).Maier, B. J., R. J. Angel, W. Marshall, 35. B. Mihailova. 2010. Structural transformations in pure and La-doped PbSc0.5Nb0.5O3 under high pressure. – Annual report 2009 ISIS-Rutherford Appleton Laboratory. Maier, B. J., A-M. Welsch, R. J. Angel, 36. B. Mihailova, J. Zhao, J. M. Engel, L. A. Schmitt, C. Paulmann, M. Gospodinov, A. Friedrich, U. Bismayer. 2010. A-site doping induced renormalization phenomena in PbSc0.5Nb0.5O3 under high pressure. – Phys. Rev. B, 81, 174116/1-8.Maier, B. J., R. J. Angel, 37. B. Mihailova, J. Engel, A.-M. Welsch, C. Paulmann, M. Gospodinov, U. Bismayer. 2010. Pressure-induced X-ray diffuse scattering in Pb-based perovskite-type relaxor ferroelectrics. – Annual report 2009 DESY.Maier, B. J., R. J. Angel, 38. B. Mihailova, J. Engel, A.-M. Welsch, C. Paulmann, M. Gospodinov, U. Bismayer. 2010. High-pressure structural state of La-doped PbSc0.5Ta0.5O3 and PbSc0.5Nb0.5O3 relaxor ferroelectrics. – Annual report 2009 DESY.Maier, B. J., R. J. Angel, W. G. Marshall, 39. B. Mihailova, C. Paulmann, J. M. Engel, M. Gos-podinov, A.-M. Welsch, D. Petrova, U. Bismayer. 2010. Octahedral tilting in Pb-based relaxor ferroelectrics at high pressure. – Acta Cryst. B, 66, 280–291.Malinov, O., S. Djambazov, 40. O. Petrov. 2010. Clinoptilolite-containing rocks at the SW foot of Chala elevation, Haskovo region (Bulgaria) – position and genesis (extended abstract). - Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 178–179. Milakovska Z., 41. N. Lihareva. 2010. Application of the sequential extraction procedure for trace metals speciation in sediments and dump materials (East Maritza Basin, Bulgaria). – Compt. rend. Acad. bulg. Sci., 63, 11, 1609–1618. Milenov, T. I., P. M. Rafailov, C. Thomsen, A. V. Egorysheva, 42. R. Titorenkova, L. Yankova, M. N. Veleva, S. Dobreva, V. M. Skorikov. 2010. Raman Spectroscopy Characterization of Se- Doped Bi12SiO20 Crystals. – 7th International Conference of the Balkan Physical Union (Ed. A. Angelopoulos and T. Fildisis 2009), American Institute of Physics Conference Proceedings (AIP CP), 1203, 228–233. ISSN: 0094-243X.Milenov, T. I., P. M. Rafailov, M. V. Abrashev, 43. R. P. Nikolova, A. Nakatsuka, G. V. Avdeev, M. N. Veleva, S. Dobreva, L. Yankova, M. M. Gospodinov. 2010. Growth and characterization of La2CoMnO6 crystals doped with Pb. – Materials Science and Engineering B, 172, 80–84 doi:10.1016/j.mseb.2010.04.021.Mouchovski, J. T44. ., K. A. Temelkov, N. K. Vuchkov. 2010.The growth of mixed alkaline-earth fluorides for laser host applications. – Progress in Crystal Growth and Characterization of Materials (doi:10.1016/j.pcrysgrow.2010.09.003).Petkova, V45. ., V. Yaneva. 2010. Evaluation of the mechano-chemical effect on the Tunisian carbonate substituted Apatite. – Journal of the Balkan Tribological Association (JBTA), ISSN 1310-4772, v. 16 (3), 421–433. Petkova, V.46. , V. Yaneva. 2010. Phase transformation of mechanically activated nano-sized Tunisian carbonate substituted Apatite. Part II. – Journal of the Balkan Tribological Association (JBTA), ISSN 1310-4772, v. 16 (1), 88–100.

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Petkova, V47. ., V. Yaneva. 2010. Thermal investigations on phase transformations of Syrian phosphorite: Part III. – Journal of the Balkan Tribological Association (JBTA), ISSN 1310-4772, v. 16 (2), 223–232. Petrova, N.48. , L. Filizova, G. Kirov. 2010. Mutual ion-exchange of the cationic pairs between K+, Na+, Ba2+ and Ca2+ in clinoptilolite at 30 and 90°C (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 210–211. Petrova, N., V. Petkova49. . 2010. Tribochemical modification of natural apatite and NH4-exchanged clinoptiolite for environmental applications (extended abstract). – Book of Ab-stracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 212–213.Peytcheva, I., A.von Quadt, 50. M. Tarassov, N. Zidarov, E. Tarassova, V.Andreichev. 2009. Timing and magma sources of Igralishte pluton in Ograzhden Mountain, SW Bulgaria: implications for the Permian-Triassic tectono-magmatic evolution of the region. – Geologica Balcanica, 38, 1–3, 5–14. (published in 2011).Rabadjieva, D., E. Vassileva, S. Tepavicharova, S. Shopova, 51. R. Titorenkova. 2010. Crystallization of nanosized calcium phosphates in hydrogel matrix of guar gum and xanthan gum. – NANOSCIENCE & NANOTECHNOLOGY, Sofia, 10, 175–177. ISSN 1313-8995.Rabadjieva, D., R. Gergulova, 52. R. Titorenkova, S. Tepavitcharova, E. Dyulgerova, Chr. Ba-larew, O. Petrov. 2010. Biomimetic transformations of amorphous calcium phosphate: kinetic and thermodynamic studies. – J. Mater Sci: Mater Med, 21(9), 2501–2509. ISSN: 0957-4530 (print version); ISSN: 1573-4838 (electronic version).Rabadjieva, D., 53. R. Titorenkova, R.Gergulova, St. Tepavitcharova, E. Dyulgerova, Chr. Balarew, O. Petrov. 2010. Biomimetic approach for preparation of modified calcium phosphates. – NANOSCIENCE & NANOTECHNOLOGY, Sofia, 10, 169–171. ISSN 1313-8995.Rafailov, P. M., A.V. Egorysheva, T. I. Milenov, V. D. Volodin, G. V. Avdeev, 54. R. Titorenkova, V. M. Skorikov, R. Petrova, M. M. Gospodinov. 2010. Synthesis, growth and optical spectroscopy studies of BaBiBO4 and CaBi2B2O7 crystals. – Appl. Phys. B, 101, 1–2, 185. Print ISSN 0946-2171.Salje, E. K. H., T. Beirau, 55. B. Mihailova, T. Malcherek, U. Bismayer. 2010. Chemical mixing and hard mode spectroscopy in ferroelastic lead phosphate-arsenate: local symmetry splitting and multiscaling behaviour. – J. Phys.: Condens. Matter, 22, 045403/1-6. Stamboliyska, B., V. Janevska, 56. B. Shivachev, R. P. Nikolova, G. Stojkovic, B. Mikhova, E. Popovskib. 2010. Experimental and theoretical investigation of the structure and nucleophilic properties of 4-aminocoumarin. – Arkivoc 2010 (10), pp. 62–76. Stoyanov V., 57. V. Petkova, D. Pashkouleva. 2010. Use of natural clinoptilolite for densification of the structure of white cement mortars (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 243–244.Stoyanov V., V. Petkova, O. Petrov. 2010. Effects of zeolite incorporation on the curing of 58. self-compacting white mortars (extended abstract). – Book of Abstracts, “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010, 245–246.Stoyanova, M. P., S. E. Angelova, P. Y. Petrov, 59. R. P. Nikolova, B. L. Shivachev. 2010. Synthesis of 1,2,3,4-substituted spiroheterocyclic tetrahydroisoquinoline- 1-ones and their structural similarity in water solution and in crystallohydrate solid state. – Arkivoc 2010 (2), pp. 303–314.Stoyanova, R., D. Carlier, M. Sendova-Vassileva, M. Yoncheva, E. Zhecheva, 60. D. Nihtianova, C. Delmas. 2010. Stabilization of over-stoichiometric Mn4+ in layered Na2/3MnO2. – Journal of Solid State Chemistry, 183, 1372–1379.Stoychev, K., 61. L. Konstantinov, R. Titorenkova. 2010. Enhanced Raman Scattering from LO Phonons in Doped Semiconductors. – 7th International Conference of the Balkan Physical Union (edited by A. Angelopoulos and T. Fildisis 2009), American Institute of Physics Conference Proceedings (AIP CP), 1203, 277–282. ISSN: 0094-243X.Stoychev, K., 62. L. Konstantinov, R. Titorenkova. 2010. Intensity redistribution between TO and LO phonons in the Raman spectra of doped semiconductors. – 7th International Conference of the Balkan Physical Union (Ed. by A. Angelopoulos and T. Fildisis 2009),

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American Institute of Physics Conference Proceedings (AIP CP), 1203, pp. 277–282. ISSN: 0094-243X.Tarassova, E63. ., G. Zhegova, M. Tarassov, M. Rashkova. 2010. SEM investigation of morphology and chemical composition of neo-phases formed during Er:YAG laser irradiation of human teeth. – Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 23–24 (ISSN 1313-2377). Titorenkova, R., B. Mihailova, R. Petrova,64. M. Gospodinov, L. Konstantinov. 2010. Effect of doping on the structure and Raman spectra of Bi4Ge3O12. – 7th International Conference of the Balkan Physical Union (edited by A. Angelopoulos and T. Fildisis 2009), American Institute of Physics Conference Proceedings (AIP CP), 1203, 289–293. Titorenkova, R.65. , B. Gasharova, B. Mihailova, L. Konstantinov. 2010. Attenuated total reflection infrared microspectroscopy of partially metamict zircon. – The Canadian Mineralogist, Vol. 48, 6, pp. 1297-1313. Print ISSN: 0008-4476; Online ISSN: 1499–1276.Todorov, P., E. Naydenova, 66. R. P. Nikolova, B. L. Shivachev. 2010. Ammonium hydrogen (RS)-[(5-methyl-2-oxo-1,3-oxazolidin-3-yl)methyl]phosphonate. – Acta Cryst. E66, o6 doi: 10.1107/S1600536809050338].Tosheva, L., 67. B. Mihailova, M. A. Wilson, M. A. Carter. 2010. Gravimetric study of the mass gain of moisture by as fired and reheated terracotta samples. – Journal of the European Ceramic Society, 30, 1867–1872. Tsintsov, Z., B. Banushev. 68. 2010. Agates in Bulgaria. Vanio Nedkov Publishing House, Sofia, 210 p.Vassilev, S69. ., D. Baxter, L. Andersen, C. Vassileva. 2010. An overview of the chemical composition of biomass. – Fuel, 89 (5): 913–933. Vassileva, C., S. Vassilev, D. Daher70. . 2010. Preliminary results on chemical and phase-mineral composition of Syrian petroleum coke and ash. – Compt. rend. Acad. bulg. Sci., 63 (1): 129–136.Vitov, O. 71. 2009. Mineralogical dividing and prognoses of prospecting for mineral resources in Pernik, Kyustendil and Blagoevgrad administrative districts, SW Bulgaria. – Review of the Bulgarian Geological Society, 70, 1–3, 135–149 (in Bulgarian, published in 2010).Vitov, O. 72. 2010. A model of chemical composition variations of the rocks from the Balcan-Carpathian ophiolite segment. – Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 35–36 (ISSN 1313-2377) (in Bulgarian).Vitov, O. 73. 2010. Gold production from the rivers in Kyustendil district, Western Bulgaria, before 1878 (based on topographic maps at 1:26000 scale). – Bulletin of the Regional Historical Museum of Kyustendil, Bulgaria, XVI, 179-191 (in Bulgarian).Vitov, O. 74. 2010.Stream-sediment dividing and prognoses for mineral deposits in Smolyan administrative district, Bulgaria. - Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 37–38 (ISSN 1313-2377) (in Bulgarian).Yeh, J. I., 75. B. Shivachev, S. Rapireddy, M. J. Crawford, R. R. Gil, S. Du, M. Madrid, D. H. Ly. 2010. Crystal structure of chiral γpNA with complementary DNA strand: Insights into the stability and specificity of recognition and conformational preorganization. – Journal of the American Chemical Society, 132 (31), pp. 10717–10727. Zidarov, N., O. Petrov76. . 2010. Boyleite and Zincian Rozenite – Two New Sulfate Tetrahydrate Munerals from Madan Ore District, Central Rhodopes, South Bulgaria. – Compt. rend. Acad. bulg. Sci., 63, 1, 113–120. (ISSN 1310-1331).Zidarov, N.,77. R. I . Kostov, P. Zidarov. 2010. First find of nephrite in tremolitite body from Ograzhden Mountain, Southestern Bulgaria. – Proceedings of National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 33–34. (ISSN 1313-2377).Zidarov, N78. ., R. I . Kostov, P. Zidarov. 2010. Nephrite Bearing Tremolitite. First Find in South-West Bulgaria. – Compt. rend. Acad. bulg. Sci., 63, 12, 1771–1780 (ISSN 1310-1331).Zidarova, B.79. 2010. Contemporary challenges to the Bulgarian mineralogy. – Mining and Geology, 3–4, 37–41 (ISSN 08615713) (in Bulgarian). Zidarova, B80. . 2010. Hydrothermal fluorite-forming processes in the Mikhalkovo deposit (Central Rhodopes, Bulgaria) – field observation and experimental confirmation. – N. Jb. Miner. Abh., 187, 2, 133–157 (ISSN 0077-7757).

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9.2. Publications in pressDimova, L., O. Petrov, M. Kadiyski, N. Lihareva81. , A. Stoyanova-Ivanova, V. Mikli. Preparation and Rietveld refinement of Ag-exchanged clinoptilolite. – Clay Minerals (accepted 2010)Ivanova, L., C. Popov, I. Kolev, 82. B. Shivachev, J. Karadjov, M. Tarassov, W. Kulisch, M.D. Apostolova. 2010. Nanocrystalline diamond containing hydrogels and coatings for acceleration of osteogenesis. – Diamond and Related Materials. doi:10.1016/j.diamond. 2010.11.020 (in press).Kostova, I., 83. C. Vassileva, J. Hower, M. Mastalerz, S. Vassilev, N. Nikolova. Mercury in coals and fly ashes from “Republika” and “Bobov dol” thermoelectric power plants. – Compt. rend. Acad. bulg. Sci. (in press).Kostova, I. J., J. C. Hower, M. Mastalerz, 84. S. V. Vassilev. 2011. Mercury capture by selected Bulgarian fly ashes; Influence of coal rank and fly ash carbon pore structure on capture efficiency. – Applied Geochemistry, 26: 18–27.Lilkov, V., I. Rostovski, 85. O. Petrov. Physical and mechanical characteristics of cement mortars and concretes with addition of clinoptilolite from Beli plast deposit (Bulgaria), silica fume, and fly ash. – Clay Minerals (accepted 2010). Lilkov, V., 86. O. Petrov, V. Petkova, N. Petrova, Y. Tzvetanova. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites. – Clay Minerals (accepted 2010).Lilkov, V., 87. O. Petrov, Y. Tzvetanova. Rheological, porosimetric, and SEM studies of cements with additions of natural zeolites. – Clay Minerals (accepted 2010).Maier, B. J., R. J. Angel, 88. B. Mihailova, W. G. Marshall, M. Gospodinov, U. Bismayer. 2011. High-pressure powder neutron diffraction study on lead scandium niobate. – J. Phys.: Condens. Matter, 23, 035902/1-5.Mihailova, B.89. 2011. Preface to the special issue on advanced ferroelectrics: Structure and properties. – Zeitschrift für Kristallographie (in press) http://www.oldenbourg-link.com/toc/zkri/0/0.Mouhovski, J90. . 2011. Chapter 1. Growth of single and mixed alkali earth fluoride crystals with wide application. Control of crystallization zone contamination and stability of melt-crystal interface. – In: Fluoride: Properties, Applications and Environmental Management, (Ed. B. Mullin), Nova Science Publishers, Inc. (in press)Nikolova91. , R. P., N. Nakayama, S. Bakardjieva, P. Bezdicka, V. Kostov-Kytin. 2010. Temperature-induced phase transformations of the small-pore zirconosilicate Na2ZrSi2O7.H2O. – Solid State Sciences, (in press, available online 9 July 2010. ISSN: 1293-2558).Petkova, V.92. , E. Serafimova, N. Petrova, Y. Pelovsky. Thermochemistry of triboactivated natural and NH4-exchanged clinoptilolite mixed with Tunisian Apatite. – Journal of Thermal Analysis and Calorimetry (in press).Petkova, V93. ., Y. Pelovski, D. Paneva, I. Mitov. Influence of gas media on the thermal decomposition of second valence iron sulfates. – Journal of Thermal Analysis and Calorimetry (in press).Petrova, N94. ., L. Filizova, G. Kirov. Binary cation exchange in clinoptililite involving K+, Na+, Ba2+ and Ca2+ at 30 and 95°C: a calorimetric study. – Clay Minerals (accepted 2010).Spassova, I., N. Velichkova, 95. D. Nihtianova, M. Khristova. 2011. Influence of Ce addition on the catalytic behavior of alumina-supported Cu-Co catalysts in NO reduction with CO. – Journal of Colloid and Interface Science, 354 , 777–784. Tsaneva, S., M. Hristov, V. Karatsanova, 96. Z. Tsintsov. 2010. SEM-EDAX technological studies of some unique Early Bronze Age (third millennium BC) gold artifacts from Balinov Gorun Locality near the village of Dubene, Karlovo Region, Bulgaria. – Proceedings of SEM 2010 Conference: SEM and microanalysis in the study of historical technology, materials and conservation, September 9–10 2010, British Museum, London (extended abstract) (in press).Tsaneva, S., M. Hristov, V. Karatsanova, 97. Z. Tsintsov. 2011. Archaemetric studies of gold artifacts from the early Bronze Age III, “Balinov gorun” area, village of Dubene Karlovo Region – Bulletin of the National Museum of History, V. XXIII. Tsaneva, S., M. Hristov, V. Karatsanova, 98. Z. Tsintsov. 2011. The SEM-EDAX story of one small, Early Bronze Age, gold find from the locality of Balinov Gorun, Dubene, Karlovo Region. – Archaeologica Bulgarica, XIV (in press).

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Vitov, O.99. Method for determination of the parameters of polynomial model using integrating procedures by intervals. – Review of the Bulgarian Geological Society (in press).Welsch, A.-M., B.J. Maier, 100. B. Mihailova, R. J. Angel, J. Zhao, C. Paulmann, J. M. Engel, M. Gospodinov, V. Marinova, U. Bismayer, U. 2011. Transformation processes in relaxor ferroelectric PbSc0.5Ta0.5O3 heavily doped with Nb and Sn. – Zeitschrift für Kristallographie, ahead of print http://www.oldenbourg-link.com/toc/zkri/0/0.Zidarova, B101. . 2011. Formation temperature, REE contents and optical spectra of fluorite from the Mikhalkovo deposit (Central Rhodopes, Bulgaria): genetic implications and practical significance. – Neues Jahrb. Miner. Abh., 3, (ISSN 0077-7757) (in press).

9.3. Reports at Scientific ForumsAtanasova-Vladimirova, S., A. von Quadt, P. Marchev, I. Peytcheva, 102. I. Piroeva, B. Mav-roudchiev. Petrology and geochronology of the Vitosha volcano-plutonic edifice, Western Srednogorie, Bulgaria. – XIX Congress of the Carpathian-Balkan Geological Association, Thessaloniki, Greece, 23-26 September 2010.Bogdanov. K. B, 103. Z. L. Tsintsov. PGM types and trends from Novoseltsi placers, Bourgas district, Bulgaria. – IMA2010 – 20th General Meeting of the International Mineralogical Association 21–27 August, 2010 Budapest, HungaryDimova L., O. Petrov, N. Liharevа104. , A. Stoyanova-Ivanova, V. Mikli. Preparation and characterization of Ag - exchanged clinoptilolite. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Dimova, L., B. Shivachev, R. P. Nikolova105. . Single crystal structure of pure and Zn ion exchanged clinoptilolite: Comparison of low temperature and room temperature structures and Cu vs. Mo Radiation. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, BulgariaDimova, L106. ., G. Kirov, A. Stoyanova-Ivanova, V. Mikli, 2010, EDS and XRD study of ZnCl2 occluded clinoptilolite. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Dimova, L., M. Tarassov, R. Titorenkova, R. P. Nikolova, B. Mihailova107. , T. Petrov, B. L. Shi vachev. Synthesis and optical properties of tellurium-germanium–cerium oxide. – 11th International Conference on the Structure of Non-Crystalline Materials, Paris, June 28 – July 2010.Gencheva, G., D. Tsekova, P. Gorolomova, V. Ilieva, 108. R. Petrova, B. Shivachev, T. Tosheva, E. Tashev, S. Varbanov. Copper(II) coordination polymers with dimethyl(methylenoxyaryl)oxides-based ligands. Synthesis, structure and properties. SIZEMAT2, – September 19–21, 2010, Nessebar, BulgariaGeorgieva, V., T. Todorova, D. Atanasova, M. Panaiotova, 109. L. Dimitrov, Y. Kalvachev. Investigation on Nanozeolite BETA and ZSM-5 Types Preparation. – 12th International Workshop on Nanoscience & Nanotechnology, November 26–28, 2010, Varna, постерGergova, M., L. Ivanova, 110. B. Shivachev, M. Apostolova, O. Petrov. Novel B-ring modified combretastatin A-4 analogues: synthesies and cutotoxic activity”. – SIZEMAT2, September 19–21, 2010, Nessebar, Bulgaria.Gerova, M., 111. R. Nikolova, B. Shivachev, O. Petrov. Synthesis and crystal structure Of 2-[(2,3-dihydro-2-oxo-3-benzoxazolyl)methyl]benzoic acid. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, Bulgaria.Gorolomova, P., 112. R. Petrova, B. Shivachev, V. Ilieva, D. Tsekova, T. Tosheva, E. Tashev, S. Var banov, G. Gencheva. Theoretical and experimental studies on the coordination abil-ity of 1,4-bis(dimethylphosphinylmethyleneoxy)benzene”. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, Bulgaria.Ilieva, V., 113. R. Petrova, B. Shivachev, P. Gorolomova, D. Tsekova, T. Tosheva, E. Tashev, S. Varbanov, G. Gencheva. Structural diversity in zinc(II) coordination polymers constructed with dimethyl(methyleneoxyaryl)phosphine oxyde-ligands. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, Bulgaria.Ivanova, L., C. Popov, I. Kolev, 114. B. Shivachev, J. Karadjov, M. Tarassov, W. Kulisch, J. P. Reithmaier, M. D. Apostolova. Nanocrystalline diamond containing hydrogels and coatings for acceleration of osteogenesis. – 4th International Conference on Nano Dia-mond and New Carbons (NDNC 2010), Suzhou, China (May 2010).

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Ivanova, P., N. Zidarov115. . Spinel accesories in ultramafic and mafic rocks from Gega ophiolite mélange in Ograzhden Mountain, Southestern Bulgaria. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010.Kadiyski, M116. ., Th. Armbruster. 2010. Stepwise dehydration of heulandite-Ba: A single crystal X-ray study. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Kadiyski, M.117. , Th. Armbruster. Effect of the type of exchangeable cations on the dehydration behaviour of heulandite: a comparative X-ray single crystal study. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Kalvachev, Yu118. . Dissemination and exploitation of grids in earth science. –10th International Conference – Modern Management of Mine Producing, Geology and Environmental protection, 2010, Albena, Bulgaria Karaguiozova, Z., V. Manolov, 119. M. Tarassov, S. Stavrev. Electroless iron coating on nanosized particles. – 3rd International Conference on Advanced Nano Materials, ANM 2010, 12–15 September 2010, Agadir, Morocco.Kirov, G., 120. N. Petrova. Energetic aspects of volcanic ash-water interaction and zeolitization of volcanic ash rocks. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Kostov, R. I., 121. Y. Tzvetanova, V. Vladimirov. Petrophysical characteristics and phase composition of zeolitic rocks applied to cultural heritage (Tatul rock sanctuary, Eastern Rhodopes, Bulgaria). – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Kostov-Kytin, V., N. Lihareva, R. Nikolova122. . Crystal chemical characterization and sorption ability of nano-sized microporous titanum silicates with pharmacosiderite stucture. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. Kostov-Kytin, V123. ., R. I. Kostov, P. Ivanova. State-of-the-art electronic bibliographic data base on minerals from Bulgaria. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10.Kurteva, V. B., L. M. Antonov, K. M. Fromm, 124. R. P. Nikolova, B. L. Shivachev. Azonaphthol tautomeric switches – individual enol structures”. – II-nd National Crystallographic Sympo-sium, October 21–23 2010, Sofia, Bulgaria.Lihareva, N., L. Dimova, O. Petrov, Y. Tzvetanova125. . Kinetics and equilibrium of Ag+ exchange on clinoptilolite. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. Lilkov, V., I. Rostovsky, 126. O. Petrov. Physical and mechanical characteristicс of cement mortars with addition of clinoptilolite from Beli plast deposit (Bulgaria), silica fume and fly ash: Part 2. SEM and porosimetry examinations. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. Lilkov, V., 127. O. Petrov, V. Petkova, N. Petrova, Y. Tzvetanova. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Lilkov, V., 128. O. Petrov, Y. Tzvetanova. SEM and porosity studies of cements with additions of natural zeolites. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. Lilkov, V., 129. O. Petrov, Y. Tzvetanova. Study of the pozzolanic activity and hydration products of cement pastes with addition of natural zeolites. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. Macheva, L., V. Ganev130. . Fluid enhanced metamorphic transformations of granitoid rocks into orthoschists, East Rhodopes. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010.Malinov, O., S. Djambazov, 131. O. Petrov. 2010. Clinoptilolite-containing rocks at the SW foot of Chala elevation, Haskovo region (Bulgaria) – position and genesis. – “Zeolite 2010 – 8th

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International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Marinova, I.132. Depositional Environment of Auriferous Colloform Banded Veins in the Low-Sulfidation Khan Krum Deposit, East Rhodope Mountain, SE Bulgaria. – 63nd Geological Kurultai of Turkey with international participation, 5–9 April 2010, MTD-Ankara, Turkey. Petkova, V.133. , E. Serafimova, N. Petrova, Y. Pelovsky. Thermochemistry of triboactivated natural and NH4-exchanged clinoptilolite mixed with Tunisian apatite. – 10th European Symposium on Thermal Analysis and Calorimetry, ESTAC, August 22–27, 2010, Rotterdam, The Netherlands.Petkova, V134. ., Y. Pelovski, D. Paneva, I. Mitov. Influence of gas media on the thermal decomposition of second valence iron sulfates. – 10th European Symposium on Thermal Analysis and Calorimetry, ESTAC, August 22–27, 2010, Rotterdam, The Netherlands.Petkova, V135. ., T. Kaljuvee, K. Tonsuaadu, E. Serafimova, I. Dombalov, Y. Pelovsky, “Com-parative study of the thermal behavior of mechanoactivated Natural carbonate substituted Apatites from Africa (Tunisia), Europe (Bulgaria, Estonia), and Asia (Uzbekistan)”. – 10th European Symposium on Thermal Analysis and Calorimetry, ESTAC, August 22–27, 2010, Rotterdam, The Netherlands.Petkova, V136. ., V. Stoyanov, B. Kostova, I. Donchev. X-ray diffraction analysis of decorative cement composites. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, BulgariaPetkova, V137. ., V. Stoyanov, Y. Pelovski. Thermal Behavior of hardening White self-compacting mortars. - 10th European Symposium on Thermal Analysis and Calorimetry, ESTAC, August 22–27, 2010, Rotterdam, The Netherlands.Petrova, N.138. , L. Filizova, G. Kirov. Mutual ion-exchange of the cationic pairs between K+, Na+, Ba2+ and Ca2+ in clinoptilolite at 30 and 90°C. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010. 139. Petrova, N., V. Petkova. Structural changes in the system natural apatite-NH4 clinoptilolite during triboactivation. – II-nd National Crystallographic Symposium, October 21–23 2010, Sofia, Bulgaria.Petrova, N., V. Petkova140. . Tribochemical modification of natural Apatite and NH4-exchanged clinoptiolite for environmental applications. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Rabadjieva, D., R. Gergulova, 141. R. Titorenkova, S. Tepavitcharova, E. Dyulgerova, O. Pet rov, Chr. Balarew. Biomimetic synthesis and transformations of dicalcium phosphate dihydrate. – 14th International Symposium on Solubility Phenomena and Related Processes, Montan-universität Leoben, Austria, July 25–30, 2010.Rabadjieva, D., S. Tepavitcharova, R. Gergulova, K. Sezanova, 142. R. Titorenkova, E. Dyul-gerova, O. Petrov. Mg and Zn Modified Calcium Phosphate Ceramics. – Second Workshop on Size-Dependent Effects in Materials for Environmental Protection and Energy Application, September 19–21, 2010, Nessebar, Bulgaria.Rabadjieva, D., S. Tepavitcharova, R. Gergulova, K. Sezanova, 143. R. Titorenkova, E. Dyul-gerova, O. Petrov. Ion modified calcium phosphate ceramics. – Fifth Workshop on Biological Activity of Metals and Metal Compoundswith the Satellite Symposium “Advanced matherials in biology and medicine: challenges and perspectives”, 24–25 November, 2010 Sofia, Bulgaria.Rabadjieva, D., S. Tepavitcharova, R. Gergulova, 144. R. Titorenkova, E. Dyulgerova, O. Petrov, Chr. Balarew. Biomimetic transformations of calcium phosphates – thermodynamic and kinetic studies. – Second Workshop on Size-Dependent Effects in Materials for Environmental Protection and Energy Application, September 19–21, 2010, Nessebar, Bulgaria.Rabadjieva, D., S. Tepavitcharova, R. Gergulova, 145. R. Titorenkova, E. Dyulgerova, O. Petrov, Chr. Balarew. Biomimetic modifications of amorphous calcium phosphate for bi-phase ceramics preparation. – 12th Workshop Nanoscience & Nanotechnology 2010 and Cosent: 12 Years Later, 26–28 November 2010 Varna, Bulgaria.Rabadjieva, D., S. Tepavitcharova, R. Gergulova, 146. R. Titorenkova, E. Dyulgerova, O. Petrov, Chr. Balarew. Amorphous calcium phosphate for bi-phase ceramics preparation. – Fifth Workshop on Biological Activity of Metals and Metal Compoundswith the Satellite Symposium “Advanced matherials in biology and medicine: challenges and perspectives”, 24–25 November, 2010 Sofia, Bulgaria.

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Stanchev, S., 147. R. Nikolova, B. Shivachev, I. Manolov. Crystal structure of 3-oxo-2-(4-hydroxybenzylidene)-butyric acid ethyl ester. – II-nd National Crystallographic Symposium, October 21-23 2010, Sofia, Bulgaria.Stoyanov V., 148. V. Petkova, D. Pashkouleva. Use of natural clinoptilolite for densification of the structure of white cement mortars. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Stoyanov V., 149. V. Petkova, O. Petrov. Effects of zeolite incorporation on the curing of self-compacting white mortars. – “Zeolite 2010 – 8th International Conference of the Occurrence, Properties, and Utilization of Natural Zeolites”, Sofia, Bulgaria, 10–18 July 2010.Tarassov, M., E. Tarassova, I. Piroeva, R. Titоrenkova150. . Electron microscopy investigation of monazite hydrothermal alteration in Igralishte granite pluton, Southwestern Bulgaria. – 7th International Symposium on Eastern Mediterranean geology, 18–22 October, 2010, Adana, Turkey.Tarassov, M., E. Tarassova, I. Piroeva, R. Titоrenkova151. . EPMA and TEM study of monazite hydrothermal alteration in Igralishte granite pluton, Southwestern Bulgaria. – XIX Congress of the Carpathian-Balkan Geological Association, Thessaloniki, Greece, 23–26 September 2010. Tarassova, E., M. Tarassov, E. Tacheva152. , R. Nedialkov. Accessory magnetite and ilmenite from mixed magmas of Petrohan pluton, western Balkan, Northwest Bulgaria. – 63nd Geological Kurultai of Turkey with international participation, 5–9 April 2010, MTD-Ankara, Turkey. Tarassova, E.153. , G. Zhegova, M. Tarassov, M. Rashkova. SEM investigation of morphology and chemical composition of neo-phases formed during Er:YAG laser irradiation of human teeth. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010. Titorenkova, R. N. Petrova, R. Nikolova, V. Kostov-Kytin, V. Ganev154. . Spectroscopic characterization of nano-sized microporous titanosilicates with pharmacosiderite structure. – II-nd national Crystallographic Symposium, October 21–23, Sofia Titorenkova, R.155. , D. Rabadjieva, O. Petrov, R. Gergulova, St. Tepavitcharova, E. Dyulgerova, L. Konstantinov. Biomimetic synthesis and characterization of Zn-substituted calcium phosphates. – IMA2010 20th General Meeting of the International Mineralogical Association 21–27 August, 2010 Budapest, Hungary.Tsaneva, S., M. Hristov, V. Karatsanova, 156. Z. Tsintsov. SEM-EDAX technological studies of some unique Early Bronze Age (third millennium BC) gold artifacts from Balinov Gorun Locality near the village of Dubene, Karlovo Region, Bulgaria. – SEM 2010 Conference: SEM and microanalysis in the study of historical technology, materials and conservation, September 9–10 2010, British Museum, London. Tzvetanova, Y., O. Petrov157. . Quantitative analysis of garnet solid solutions from skarn zones using Rietveld-based XRD method. – II-nd National Crystallographic symposium, October 21–23, 2010, Sofia.Vitov, O. 158. 2010.Stream-sediment dividing and prognoses for mineral deposits in Smolyan administrative district, Bulgaria. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010.Vitov, O. 159. A model of chemical composition variations of the rocks from the Balcan-Carpathian ophiolite segment. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010.Zidarov, N160. ., R. I . Kostov, P. Zidarov. First find of nephrite in tremolitite body from Ograzhden Mountain, Southestern Bulgaria. – National Conference with International Participation “GEOSCIENCES 2010”, Sofia, December 9–10, 2010.

9.4. Popular scientific papersDamyanov, Zh. 161. 2009. The long-awaited book for the Bulgarian “stone-flowers”. – Review of the Bulgarian Geological Society, 70, 1–3, 209–210 (in Bulgarian, published in 2010).Tarassova, E. 162. 2009. General Assembly of the Bulgarian Geological Society – 2009. – Reviews of the Bulgarian Geological Society, 70, 1–3, 196 (in Bulgarian, published in 2010).Tarassova, E. 163. 2009. Geology of Bulgaria, vol. II, Mesozoic Geology. 2009. Sofia, Prof. Marin Drinov Academic Publishing House, 765 p. – Review of the Bulgarian Geological Society, 70, 1–3, 208 (in Bulgarian, published in 2010).

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Tarassova, E. 164. 2009. National scientific conference with international participation “Geoscience 2009”. – Review of the Bulgarian Geological Society, 70, 1–3, 197 (in Bulgarian, published in 2010).Zidarova, B. 165. 2010. To Jubilee of Professor DSci Dobrinka Stavrakeva. – Mining and Geology, 7–8, 62 (ISSN 08615713) (in Bulgarian). Zidarova, B. 166. 2010. What is it science? Steps 3 – poetry of Bulgarian scientists. – Publication of the Union of Scientists in Bulgaria. EU Program “Researchers Night 2010”, p. 84. (ISBN 978-954-9928-31-0) (in Bulgarian).Zidarova, B. 167. 2010. Zapryanov’s family – four generations devoted to the medicine in Bulgaria. – Newspaper “Homo Sciens”, 4, 5–6 (ISSN 13128884) (in Bulgarian).