It is shown that the market is interested in high-quality enamel frits suitable for artistic painting on metal. Brief historical information on enameling is given. The compositions of enamels must be studied more thoroughly in order to re-establish the technique of artistic enameling. The requirements for such materials are formulated. A method for synthesizing the materials in the laboratory is described and their properties are indicated.

The article examines two ways to achieve mastery of undergraduate mathematics: face-to- face and digital learning formats. The authors have developed and tested a unique interactive computer-based learning software – few local programs to practice math online, offline or to be installed into an e-course. We focus on different standard problems, such as, finding determinants, solving differential equations, integration by parts, etc. The aim of this study was to investigate what kinds of the activities lead to good learning outcomes. To date, much of the previous research has suggested that students get the benefits of e-learning and b-learning. Yet, there is a general lack of research on outcomes compares the different ways in which students gain knowledge. The results show that the interactive math simulator is one of the effective tools for developing skills to solve standard problems of higher mathematics. There are, however, some math problems to be learn traditionally, with textbook and chalkboard.

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The problems of enamel frits are examined. Enamel compositions are worked out using different opacifiers. It is shown how an opacifier affects the properties of and coverage by enamel. The reasons for opacification of a material are determined.Jewelry made from precious metals decorated with enamel is in demand again. Enameling in Rus' has been known since the 13 -14th centuries. The most brilliant master enameller C. P. Fabergé, who became famous for his series of exquisite Easter eggs, is still considered to have worked at the juncture of the 19th and 20th centuries. The articles made by this great master are recognized standards in this field. And even though the world market places a strong emphasis on so-called cold enamels, hot enameling and painting on metal will always be in demand. Fabergé's palette contained up to 130 basic colors, including compositions with opacification and opalescence. This type of enamel with different degrees of opacification is in great demand by jewelers as a coating forming a background for painting on metal. In the USSR such enamels were made at the Druzhnaya Gorka Works (DGW) in Leningrad Oblast. Unfortunately, DGW was closed in 1990 and the prescriptions for the mixes were lost.Attempts to obtain similar enamels have been made repeatedly in different countries. But it was found to be impossible to use the newly developed compositions under the conditions of an ordinary jeweler's workshop because of the presence of at least one of the indictors presented below:-high deposition temperature for enamel on the substrate (above 800°C); this results in deformation of the complicated piece of jewelry because of solder spreading;-absence of a strong bond between the decorative enamel and substrate because of the large difference between their CLTEs (in experimental work copper fragments are used as the substrate; it is believed that if the enamel -copper bond is good, then the enamel is guaranteed to be suitable for deposition of precious metals also); -low acid resistance of the enamel when the article is whitened in hydrochloric acid after kilning.It should be noted that the enamels used by C. P. Fabergé and produced at the DGW did not have these drawbacks.An enamel composition which has none of the drawbacks mentioned above was developed in the Department of the Chemical Technology of Glass and Sitals at the D. I. Mendeleev Russian Chemical Technology Institute. This is a potassium-lead-silicate glass, exhibiting good bonding to a copper substrate. The objective of the present study was to develop on its basis opalescent enamels with different degrees of opacification. It is known that the opacifiers used for obtaining opaline and frosted glasses are fluorine and phosphorus compounds [1 -4]. Aside from fulfilling their principal function of opacifying glass, the additives introduced must not degrade either the coverage by the enamel or the physical-chemical properties of the enamel.The mix for obtaining enamels consisted of pure and analytical grade raw materials. The powders were...

АннотацияЦель. Развитие новых принципов управляемых оптических элементов -дифракционных, фокусирующих и дифракционно-фокусирующих -в широком диапазоне их применения, и в том числе как для оптического, так и для инфракрасного излучения. Процедура и методы. Показана перспективность для решения поставленной задачи ЖК композитов 4-циано-4-октилоксидифенил (8ОЦБ) в боросилоксановых (БС) матрицах. Методика фиксации пространственного распределении ЖК-композитов заключается в их предварительной пространственной ориентации по некоторому заранее заданному плану (при температуре выше 55 °С -температуры плавления) и последующем охлаждении. Цикл нагрев-охлаждение технически легко реализуем. ЖК-композит ориентируется различными способами, и в данной работе предложено использовать с этой целью светоориентирование. Результаты. Предложена светоуправляемая ЖК линза с регулируемыми параметрами. Рассмотрена как принципиальная возможность многократной перезаписи центросимметричных фазовых пластин с анизотропной ориентацией молекул в тонкой пленке, так и обеспечивающая плавное изменение оптической оси техника записи элементов, с цилиндрически-симметричным и планарно-симметричным распределением. Теоретическая и практическая значимость. При смене режимов неуправляемые элементы приходится заменять, что бывает неудобно. Управляемые оптические элементы обычно