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1 07.2. Dr. sc. Biserka Gržeta, physicist, Senior scientist Department of Materials Chemistry, RBI 15 Nov. 2002 MATERIAL FOR RBI BUSINESS PLAN A. FUNDAMENTAL RESEARCH A1. Scientific project 0098067 Project Title: Influence of dopands on structure and properties of materials for technical applications Principal Investigator: Dr. sc. Biserka Gržeta Summary: Nowadays many investigations in the fields of physics and chemistry are aimed towards a research of the properties of new materials, but also towards discovering of new techniques which could improve the properties of the well known materials and make them interesting for a modern technology. It has been found that a doping of materials by selected atoms very often causes such improvements of material properties, but a mechanism of the doping process is not well understood in all cases. The subject of this project is an investigation of the doping mechanism and its effect to mullite (3Al2O3.2SiO2), SnO2 and In2O3. // Solid solutions in a specific range of the Al2O3-SiO2 system are known under the name mullite. During last decade mullite has been recognized as a very interesting material for technical applications at high temperature. It has a great mechanical firmness, high chem. stability, high el. resistivity, IR transparency, low coef. of thermal expansion, and a great creep resistivity even at 1400oC. Doping of mullite with transition metals even improves these properties. // On the other hand, doping of SnO2 and In2O3 leads to the change in their el. conductivity: transparent semiconductors SnO2 and In2O3 become transparent conductors when doped with Sb and Sn respectively. Thin films of transparent conductors are used as transparent heating elements for aircraft windows, antistatic coatings for instrument windows, and in production of solar cells. While the optical and el. properties of new transparent conductors are subjected to detailed investigations by many authors, very often it is not the case whith the structure. This is so because such materials can not be prepared in a single crystal form. However, application of the Rietveld method for determination of the crystal structure of polycryst. sample solves this problem. The same is valid for doped mullite. Nevertheless, works of this kind are not frequent in the literature. // In the scope of this project a series of powdered mullite samples doped with Cr, Zn, Ni, Co, a series of Sb doped SnO2 samples, and a series of Sn doped In2O3 samples will be prepared 2 by a sol-gel techniques. Crystal structure of each sample will be solved by means of the Rietveld method. The measurements of thermal expansion and of el. conductivity will be performed, and the results will be correlated with the structure. This will be a contribution to fundamental knowledge about the doping mechanism in materials, and important support to the future design of new advanced materials. A2. Work in the international scientific organizations 1. Dr. Biserka Gržeta is a Member of the International Centre for Diffraction Data, Newtown Square, PA, USA., and a Member of its Technical Subcommittees: a) Ceramics b) Metals and Alloys c) X-ray Diffraction Methods. 2. Dr. B. Grzeta is a Substitute to national representative of Croatia to the Committee of the European Crystallographic Association 3. Dr. B. Gržeta is a Member of the Planetary Society, Pasadena, CA, USA. B. EDUCATION B1. Participation in postgraduate studies Dr. sc. Biserka Gržeta is Lecturer in Crystallography on postgraduate studies at the University of Zagreb since 1996 in subject: "Experimental methods in crystal structure analysis". Did complete training of several PhD students in the work of using the Rietveld method and other fitting methods for the structure determination from polycrystalline materials. Did training of several co-workers and postgraduate students in using powder diffraction methods for qualitative and quantitative phase analysis. B2. Proposition of new studies on RBI I think that Ruđer Boškovic Institute has all resources for starting the undergraduate and postgraduate studies in Materials science. 3 C. TECHNOLOGY DEVELOPMENT AND SUPPORT C1. Technological project TP-01/0098-29 (proposal under estimation) Project Title: Characterization of the calcium-aluminate-cement clinker by the Rietveld method Principal Investigator: Dr. sc.Biserka Gržeta Partner from Industry: Factory Istra Cement International , Pula, Croatia Summary: An application of the Rietveld method in quality control of the calcium-aluminatecement clinker will be worked out in detail. The procedure will enable quick and simple control of clinker phase composition in production line, and control of composition and structural properties of the mineral phases present in the clinker. The results of this project will be applicable to our cement industry in general, so it can be assumed as an important contribution to the technological improvement of our country. C2. Technological Support Type of technological support: We perform a technological support to our industry on the basis of consultancies and expertises using X-ray diffraction phase analysis of polycrystalline samples. Sometimes we have short-term projects with our industry clients. Our X-ray diffraction work has affected the quality of specific industrial products or solved several problems in a production line. Industrial clients: 1. PLIVA, Zagreb, Pharmaceutical industry 2. Istra Cement International, Pula, Cement plant 3. Željezara, Sisak, Iron plant 4. TEŽ - Tvornica žarulja, Zagreb, Factory of electrical lamps 5. ELKA, Zagreb, Factory of electrical cables 6. Petrokemija, Kutina, Fertilizer plant and Carbon black plant 7. Durolit, Zagreb, Ceramics factory 8. Inker - Polo rudnici, Zagreb, Mine company 4 D. RBI SERVICES Dr. sc. Biserka Gržeta is a winner of the Certificate for quality of work awarded by the International Centre for Diffraction Data, Newtown Square, PA, USA. Type of services: We perform measurements of X-ray diffraction in polycrystalline samples and can perform a complete qualitative and quantitative phase analysis. Also, we can analysise specific structural properties of materials such as: stress and strain in materials, crystallite sizes and preferred orientation. Determination of crystal structure from powder samples is also included. We are performing X-ray powder diffraction measurements, analyses and consutlancies for: 1. Faculty of science, University of Zagreb, Zagreb 2. Faculty of machinery and ship-building, University of Zagreb, Zagreb 3. Faculty of pharmacy, University of Zagreb, Zagreb 4. Faculty of chemical engineering and technology, University of Zagreb, Zagreb 5. Faculty of metallurgy, Sisak 6. Technical faculty, Rijeka 7. Institute for geological research, Zagreb 8. Energozavod zaštita, Zagreb, Company for quality control of industrial products 9. Tehnozaštita, Zagreb, Company for technology and quality engineering 10. PLIVA, Zagreb, Pharmaceutical industry 11. Istra Cement International, Pula, Cement plant 12. Željezara, Sisak, Iron plant 13. TEŽ - Tvornica žarulja, Zagreb, Factory of electrical lamps 14. ELKA, Zagreb, Factory of electrical cables 15. Petrokemija, Kutina, Fertilizer plant and Carbon black plant 16. Durolit, Zagreb, Ceramics factory 17. Inker - Polo rudnici, Zagreb, Mine company. 5