Topicality and demand of the theme of dissertation. One of the actual problems of modern physical chemistry and macromolecular chemistry is the study on the development of the fundamentals of synthesis of functional polymers with ion-exchange and complexing properties.
Anion exchange and complexing compounds based fibrous materials have a high specific surface area, which provides a high possibility of sorption and desorption processes. They arc especially effective in removing toxic substances, even at very low content of the latter from the air and water pollution. Of particular interest is the acrylic fiber "Nitron", which is produced by JSC "Navoiazot" (Uzbekistan).
In the Academy of Sciences of the Republic of Uzbekistan, Tashkent Institute of Textile and Light Industry conducted research on the development of fibrous ion exchange materials based on acrylic fiber "Nitron" but they have not been brought to its logical end. In addition, when these studies neglected the study of the physicochemical aspects of the preparation of these materials.
In developing the fundamentals of ion exchange materials obtaining a lot of attention paid to the study of physical and chemical aspects of the synthesis and properties of these high-molecular compounds. These studies due to the fact that they allow you to adjust the processes of synthesis and, therefore, necessary to obtain polymers with required composition and with complex specific properties.
As noted above, to date, no attention was paid to the study of the physicochemical foundations of anion exchangers and polycomplcxons, due to applied research conducted to date in this field of research. In this regard, the study of physical and chemical principles of bases of creation, and the properties of anion exchangers and polycomplcxons based on acrylic fiber "Nitron" arc actual both from a theoretical and practical point of view.
Demand perform of the dissertation is characterized by the fact that modern worldwide technology for extraction of non-ferrous and precious metals can not be realized without the use of ion-exchange materials. These techniques use mostly granular sorbents, while fibrous sorbents comprise just 2-3 % of the ion exchange materials used . Using technology employing ion exchange material from algae and natural brine deposits of oil and gas recovered to 90% of iodine and bromine, lodinc-containing sorbents arc used for disinfection of drinking water from microorganisms and extraction of mercury from wastewater and gas emissions. They can be used for concentrating the processing solutions and biologically active substances in the preparation of catalyst systems nanoparticles metals. It should also be noted that Uzbekistan hitherto not been established as industrial manufacture granular and fibrous sorbents, although such polymers arc widely used in industry.
The purpose of this study is to identify the physico- chemical characteristics of the formation and properties of anion exchangers polycomplcxons based on acrylic fiber " Nitron ".
Scientific novelty of disscrtational research consists in the following:
in the first time studied the kinetics of the interaction of acrylic fiber "Nitron" with nitrogen-containing bases in aqueous and organic media;
shown that due to the high surface area fibers arc modifiable , the reaction rate depends on the concentration of the nitrile groups of the polymer being in the solid surface;
proved previously identified mechanism of the catalytic action of small amounts of hydroxylaminc on the process of modifying of fiber " Nitron " with nitrogen-containing bases;
in the first lime developed a method for producing anion exchangers branched structure by sequential treatment of acrylic fiber " Nitron " with cthylcncdiaminc and dichlorocthanc;
found that the interaction of PAN - fibers with hcxamcthylcnc- and ethylene diamines formed anion exchange fibrous materials having in its composition as a weakly basic and strongly basic functional groups ;
in the first time obtained new polycomplcxons with ampholytic properties by reacting maleic anhydride with amine -modified polyacrylonitrile fiber " Nitron " or by hydrolysis of residual of the nitrile groups modified with diamines of acrylic fiber "Nitron";
established values of the thermodynamic equilibrium constants of adsorption of ions Cr (VI), Си (II), halogens, Arsenazo (III) by synthesized anion exchangers and polycomplcxons and alteration in thermodynamic functions of the process testify to high sorption capacity of these ion-exchange materials with respect to the sorption ions;
Conclusion
1. Values degree reaction of the nitrile group and a nitrogenous base, the activation energy of the process shows that the process of modifying fiber " Nitron " nitrogen-containing bases subject to the usual regularities observed in homogeneous reactions. This effect is due to a high fiber surface area to be modified, allowing the reactants to facilitate access to the nitrile groups of the polymer. (Physical chemistry, High molecular compounds).
2. Kinetic studies of the reaction of acrylic fiber " Nitron " with diamine (hexamethylene and ethylenediamine) showed that the change of physical and chemical parameters of the modification process can be controlled sorption properties, chemical resistance and the strength of the anion exchangers due to network structure of the polymer. It has been established that this modification "Nitron" produces strongly basic anion character especially in organic media. Strongly basic anion exchangers possibility of obtaining a high sorption capacity with graft polycthylcnpolyaminc chain reactions revealed in fiber modification "Nitron " ethylenediamine in the presence of dichloroethane. (High molecular compounds, Physical chemistry ).
3. IR - spectroscopic and analytical determination of the formation of intermediate amidoxime groups in the polymer chains and free hydroxylaminc after substitution reaction proved previously proposed mechanism of the catalytic action of hydroxylaminc on the process of chemical modification of acrylic fiber " Nitron " nitrogen-containing bases . ( Physical Chemistry).
4. Developed conditions of synthesis polycomplcxons reacting maleic anhydride with modified by hcxamcthylcncdiaminc acrylic fiber "Nitron" and with of hydrolysis of residual nitrile groups modified by hcxamcthylcnc- and cthylcncdiamin of acrylic fibers . (High molecular compounds, Physical Chemistry).
5. Alkalinity obtained anion exchange resins depends on the nature of their functional groups. Strongly basic anion exchangers have in their composition cyclic amidine groups and they arc formed by the reaction of polyacrylonitrile fiber with a diamine. The specific surface area obtained fibrous sorbents exceeds by two orders of known surface area granular ion exchange resins, and their crosslinking rate is up to 100 nodes per macromolecule polymer. ( Physical Chemistry )
6. Kinetics and thermodynamics of the sorption of various inorganic and organic ions obtained polycomplcxons sorbents showed that ions of Cr (VI), Arsenazo (111) can be sorbed strongly basic anion exchangers only, and the process of sorption of copper (II) with polycomplcxons occurs not only due to the ion exchange, but also due to chelation. ( Physical Chemistry ).
7. Developed the conditions obtaining bromide complexes of polymers and kinetics, thermodynamics of the sorption halogen anion in synthesized materials was studied. It is shown that the lower the stability of the ion [Bn]’ for ion [J3]'than the ability to form such molecular chlorine ions leads to the fact that almost no molecular chlorine is adsorption, and molecular bromine is absorbed to a lesser extent than the molecular iodine. (Physical Chemistry ).
8. Combined developed iodinated anion exchange materials based on acrylic fiber " Nitron " and chitosan. Insertion of the iodinc-containing chitosan materials, leads to an increase of absorbent capacity. Combined antibacterial dressings have a pronounced anti-inflammatory and antibacterial effect, arc effective for the treatment of necrotic soft tissue diseases. (High molecular compounds, Physical Chemistry).
Изучение иностранного языка всегда сопряжено с множеством проблем. Среди этих проблем на первом месте стоит подлинность материалов. Возможность получать обновленные материалы является преимуществом на уроках английского языка. Многие книги, аудио материалы, видео и компакт-диски часто устаревают к моменту поступления в класс. Это часто создает проблемы для учителей, поскольку они обычно вынуждены использовать только те материалы, которые используют на своем рабочем месте. Используя интернет студенты и преподаватели могут найти любую необходимую для проекта информацию: о музеях и их выставках по всему миру; о текущих событиях в разных уголках мира и реакции людей на эти события; об экологической ситуации в разных частях мира; о национальных праздниках; статистика по. широкий спектр вопросов и т. д.
В настоящее время не утратило своей актуальности создание новых прогрессивных энерго- и ресурсосберегающих технологических процессов, обеспечивающих использование вторичного сырья, шлаков и других отходов промышленности. В стратегии по переходу Республики Узбекистан на «зеленую» экономику на период 2019 — 2030 годов, для повышения энергоэффективности базовых отраслей, в частности в сфере производства строительных материалов, были предусмотрены увеличение объемов использования вторичных ресурсов и крупнотоннажных техногенных отходов отраслей промышленности (энергетики, металлургии, химии) при производстве строительных материалов, а также внедрение инновационных энергоэффективных технологий по производству строительных материалов.
Subject of the inquiry is the social structure of society in the territory of Uzbekistan and its transformations in conditions of colonial and Soviet regimes.
Aim of the inquiry: is a complex investigation of transformations of the social stratification of society in the territory of Uzbekistan in close entwinement with political and socioeconomic events during the period from the end of the 19lh century up to the end of the 1930s.
Method of the inquiry: the research has employed the problcm-and-chronological and retrospective-historical methods, the methods of comparative and of system analyses.
The results achieved and their novelty: the dissertation is the first to make an attempt of approaching the studying of the problem of social stratification of society in the territory of Uzbekistan and to do a complex, multifaceted research covering a long historical period. The research was pursued from the new conceptual - methodological positions of the theory of stratification of society, what has not been used in domestic historiography until now.
Practical value: the materials systematized in the dissertation can help and contribute to more profound knowledge of the historical past of Uzbekistan thereby assisting to the formation of the worldview and ideology of the youth.
Degree of embed and economic efficiency: the material of the disscrtational work is reflected in 38 publications including the monograph, 21 journal articles(including three articles in foreign journals), and three educational books. Currently these publications are used by university students and researchers.
Sphere of usage: material of the research might be useful to scholars of social and political sciences, to historians in their writing works on the history of Uzbekistan and in writing scientific-methodical study guides for students of higher education establishments and secondary-special educational institutions, as well as for professional training of high-skilled specialists.
This article devates and analyzes information on trade and economic relations between the Emirate of Bukhara and Afghanistan in the works of tourists, ambassadors, diplomatic officials and researchers during the 19th and early 20th centuries. In particular, the article by Gabaidulla Amirov, published in the journal «Aziatskiy Vestnik» in 1825, examines the important aspects of Bukhara-Afghanistan trade relations at the time, as well as the activities of Bukhoro traders in other cities, such as Herat, Kabul, and shopping centers in Afghanistan. This article examine caverfully the wook of E.K. Meindorf one of the naturalist (or scientist) from the expedition led by A.F. Negri in the Emerate Bukhara in 1820-1821. The informations about agricultural cotton, which produced in connection with foreign trade of Bukhara to Afganistan and the trade routes passes through Balkh to Kabul and through Bukhara to Herat, is highlighted in. The article notes that the special attention has paid to the trade relations between the Emerate of Bukhara and Afganistan since the 1930. In the work of Russian orientalist P.S. Savelyev analyzes the role of Bukhara in the trade relations of the eastern states and the three caravan routes passed through Bukhara to Iran and Afganistan. In this period Burns, who was sent to Central Asia on a special mission from the British government at that time, will examine the issue of the Afghans in Bukhara, P.I. Demezon, who was sent as an ambassador to Bukhara in 1833-1834, and the information collected by the Russian officer I.V. Vitkevich in 1835-1836, were investigated. N.V. Hanikov's work in the 40s of the 19th century examines information about goods imported from Bukhara from Afghanistan, as well as trade convoys between Bukhara and Kabul, as well as trade goods. In addition, their trade activity, and especially the Lohanians, the Afghan tribes living in the Ghazna district. Since the 50s of the 19th century, Russia has attached great importance to the study of the relations of Central Asian khanates with Afghanistan. Moreover, traditional goods from Bukhara to Kabul, such as silk, goat wool and wool, had based on research by P. Nebolsin, a member of the Russian Geographic Society. The Russian, copper, pot, crust, knives, scissors, tin, leather, razor, gold yarn, cashmere the so-called red paint, lightweight silk fabrics, and velvet are also included, and the distance between Bukhara and Afghanistan had discussed. In the studies of the second half of the 19th - the beginning of the 20th century, in particular, A. Vamberi, M.I. Venyukov, V.G. Grigorev, V.I. Masalskiy, M.A. Terentev, A.G. Serebrennikov. In the works of Logofet, Gubarevich-Radobilsky and others, information on trade relations between the Emirate of Bukhara and Afghanistan had examined, along with reports on socio-political and economic issues in the country.
Development of a method for local determination of an allergic reaction to the materials of future dentures in patients with bronchial asthma.
На сегодняшний день современные композитные материалы позволяют добиваться удовлетворительных эстетических результатов при восстановлении зубов в технике прямой реставрации (Николаев А.И., Гильмияров Э.М., Митронин А.В., Садовский В.В., 2015). При этом, финишная обработка поверхности композита имеет важное значение для последующей функциональной эксплуатации реставраций и их долговечности. Нередко, в целях экономии времени врачи-стоматологи пренебрегают соблюдением всех этапов полировки, сокращая тем самым срок службы реставраций и ухудшая их эстетические характеристики (Митронин А.В., Гришин С.Ю, 2011). Вместе с тем, результат финишной обработки зависит от выбора полировочных систем и соблюдения алгоритма их применения. Именно поэтому анализ микротекстуры поверхности композита после использования различных компонентов полировочной системы является актуальным для изучения, а полученные данные будут полезны врачам-стоматологам при выборе протокола эффективной финишной обработки композитных реставраций.
In connection with the growing amount of information about the methods and means aimed at treating the destructive forms of apical periodontitis it became necessary to review available literature that would form a general idea of the existing methods of treatment and highlight modern approaches to solving this problem. This review describes the methods of conservative treatment of apical periodontitis, their advantages and disadvantages. The urgency of the problem encourages scientists from different countries to develop innovative materials that contribute to the restoration of destructive processes in bone tissue, as well as methods that reduce trauma and the risks of invasive treatment.
В статье освещены материалы исследований в направлении изучения особенностей проявления у ягнят некоторых показателей расцветок и завитков в зависимости от разных вариантов подбора родителей по расцветкам. Установленысходстваиразличиявпроявленииизученныхпоказателей
This article analyzed the issue of hunger season, the source of Turkestan ASSR The author tried to clarify the issue according to present-day requirements by comparing and studying historical sources, archival documents, periodical press materials and statistical data.
In this article, classification of composite materials, current methods of production of composite materials, their advantages, materials for them, and development of production of composite materials in our country.