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Lecture № 1


INTRODUCTION

The basic purposes of the abstract of lectures are development by the students of a wide circle of questions the including items of information on properties of silicon and, about a structure and properties liquid, glassform , crystal of silicates and silicate melt, about solid phase processes occurring in silikate mixes at heating, about phase balance in manycomponent systems, graphic methods of the analysis and accounts, gives the items of information on the diagrams of a condition one, two, three and manycomponent systems.

The basic tasks of the abstract of lectures are:

- To give the students the theoretical items of information on properties of silicon and various connections;

- To learn to select optimum composition in one, two, three and manycomponent systems,

-To be able to operate technological processes and purposefully to influence

process of synthesis for reception of materials with the beforehand given operational characteristics.

In the abstract of lectures are switched on: subjects of a lecture material, the plan of realization of employment(occupation) is specified, the dictionary of the basic concepts is created, at the end of a lecture material the control questions, list of the literature are made. The development has the large meaning (importance) for the students.

The abstract of lectures is intended for the students of a speciality:

5В0753000 - Chemical technology refractory not metal and silicate of materials.

1.Introduction. The contents and meaning of discipline PCS as theoretical basis of the technology of production, fire-proof and other refractory connections. Communication of discipline with total theoretical and special disciplines. A brief history of development of PCS.

1. Meaning of discipline PCS as theoretical basis of technology and other refractory connections.

2. Brief history of development PCS.

Modification - transition of substance from one phase in another.

Homogeneous system - system, inside which there are no surfaces of the unit separating from each other a parts of system, differing on properties.




Heterogeneous system - system, inside which there are surfaces of the unit separating from each other a parts of system, differing on properties.

The subject PCS studies the modern data on artificial and natural compounds of silicon, newest items of information on system silica and its modifications.

The subject considers of phase balance in homo- and heterogeneous systems, in detail studies the diagram of a condition important silicate of systems, studies a structure melt of silicates in crystal and glasslike condition, important methods of synthesis and is engaged in study of its structure and properties.

The knowledge of these questions allows consciously and purposefully to operate processes silicate of technology. PСS is independent discipline, which in section about of silicates and other refractory connections in a crystal condition gives attention to consideration polymorphism and defects of a crystal lattice.

Brief history of development.

The art of manufacturing of ceramics by forming and burning of clay was famous of a civilization. By the most ancient product found in excavation about 15 000 of years B.C. As opposed to this manufacture cement similarly of materials has received development about 200 years back. In ancient Egypt used burnt lime as masonry mortar (кладочный раствор). Roman combined lime with volcanic ashes for manufacturing cement. Then the art was lost, but the hydraulic properties low burnt of limes again were open in England in 1750 and in following 100 years the of technology of cement was saved not having undergone changes.

By founder of a science about silicate is Lomonosov. The elements PСS are present at his work " Cours of true physical chemistry " in 1752. He in the researches about the painted glasses for the first time special attention has paid on dependence between structure and property of a glass. In 1738 I.G.Gmelin has published articles devoted physics chemistry and technology of manufacturing of porcelain.

Mendeleev in the work " Glass manufacture " for the first time has stated the scientific theory glasslike of a condition.

The doctrines about solutions and phase balance between solutions has arisen for a long time. The special place in this doctrine is borrowed jobs Гиббса which has created the theory, phase balance. He established an opportunity and necessity of study and quantitative description of laws determining a condition of phase balance. In a direction of study phase balance in silicate systems at high temperatures a conducting role the jobs Lessinga, founder of school on PСS and Kurnakova, founder of a method of the thermal analysis of silicates have played.

In study PСS and melts of the large successes achieved the scientific Lazarev, M.P.Volarovich, P.A.Appen.

The most valuable contribution has brought to a science about glass I.G.Grebenshicov by the jobs with the ultra porous glasses formed at action of diluted acids on some borosilicate of a glass.

In the field of study of the basic laws determining a course of reaction in firm phases, are known the large jobs of the academician Putnicov, Yander, Yung, Gzuravleva. In study manycomponent oxide of systems important for obtained high proof, the large job was spent Beregznyim. The numerous phisics-chemical researches in the field of synthesis of glasses and glasscrystal of materials on the basis of industrial wastes are carried spent by Pavlushkin.

Questions:

1. What is studies the discipline physical chemistry of silicates?

2. Name the scientists, which have brought in the contribution to development of physical chemistry of silicates.







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