Buildings and structures corrosion of metal structures and effectiveness of its prevention

In this article, metal structures can be partially or completely destroyed during the corrosion of building and building structures. Prepared buildings and structures, pipes, tanks, and other structural materials corrode (rust, collapse, and collapse) during operation, causing great damage to the manufacturing industry. The corrosion rate is unknown, and methods have been developed to combat corrosion

Sol–gel derived Ba/SrTiO3–MgF2 solar control coating stack on glass for architectural and automobile applications

Fully dielectric solar control coatings based on alternating layers of Ba (or Sr) TiO3 and MgF2 were deposited on soda lime glass substrates. Three-layered stacks BaTiO3/MgF2/BaTiO3 and SrTiO3/MgF2/SrTiO3 were generated using BaTiO3, SrTiO3 and MgF2 sols deposited on glass using dip coating technique. The multi-layered coating stack was fired at 450oC with different heating rates using a conventional muffle furnace and a conveyorized belt furnace, by which two methods of heat treatment were investigated. Heat treatment after deposition of each layer and a consolidated firing of the three-layered stack with intermediate drying between the layers were carried out and optical properties of the coatings compared. The heat treated coatings were characterized for their UV–Vis–NIR transmittance, microstructure, phase purity, thickness and refractive indices. The coating stack based on BaTiO3 as the high refractive index material in conjunction with MgF2 exhibited better solar control properties than SrTiO3 as the high refractive index material. Moreover, a fast firing of the BaTiO3/MgF2/BaTiO3 stack in a conveyorized belt furnace yielded good NIR blocking and solar control properties, whereas slow firing in a muffle furnace exhibited ~ 80% visible light transmittance with an NIR transmittance of ~ 75%

Optical properties of multilayer BaTiO3/SiO2 film structures formed by the sol–gel method

Multi-layer film structures BaTiO3/SiO2 with a thickness of ~1 μm containing up to 14 pairs of layers were synthesized by the sol–gel method with sequential heat treatment. It is shown that the synthesized structures are X-ray amorphous. The formation of bands in the transmission and reflection spectra caused by interference effects is demonstrated. A more regular structure exhibits a photon band gap (opacity band) in the visible range with main minimum at 636 nm and corresponding maximum in the reflection spectra. Dispersion characteristics of barium titanate films with different concentrations of initial sols were studied and an increase in the refractive index with an increase in the concentration of sol was demonstrated. For a sol with a concentration of 60 mg/ml, the refractive index in the spectral range of 390–1600 nm is 1.88–1.81. The prospects of sol–gel technology for the formation of BaTiO3/SiO2 structures for nanophotonics and solar radiation converters are discussed

ЗОЛЬ-ГЕЛЬ СИНТЕЗ И ПРОПУСКАНИЕ МНОГОСЛОЙНЫХ ПОКРЫТИЙ BaTiO3/SiO2

SOL-GEL METHOD, BARIUM TITANATE, FILTER.В работе изложены результаты формирования золь-гель методом многослойных покрытий, отличающихся показателем преломления BaTiO3/SiO2, на кварцевых и кремниевых подложках. Показано, что многослойные покрытия после термообработки при температуре 450 ºС формируют полосу непрозрачности на спектре пропускания с минимумом 693 нм для 14 пар слоев BaTiO3/SiO2, уменьшая пропускание до 35 %, при этом пропускание в ИК-диапазоне 1000-2000 нм ослабляется до 70-75 %. Пленки являются рентгеноаморфными после термообработки при температурах 450 и 600 ºС. Обсуждается перспектива применения разрабатываемых фильтров для оптики и нанофотоники

КОНДЕНСАТОРНЫЕ СТРУКТУРЫ НА ОСНОВЕ ПЛЕНОК ТИТАНАТА БАРИЯ, СФОРМИРОВАННЫХ ЗОЛЬ-ГЕЛЬ МЕТОДОМ

The objective of the work is investigation the dielectric permittivity and dielectric loss tangent of BaTiO3 films in a capacitor structure formed by sol – gel method on a Si/TiOx/Pt substrate. The basis of this capacitor is a four-layer film of barium titanate xerogel with a thickness of about 200 nm. The film was synthesized by sol-gel method at a final annealing temperature 750 °C. The problems related to the development of method of forming multilayer capacitor structures, the analysis of the morphology and phase composition of BaTiO3 film, and also the measurement of the capacitance-voltage characteristics in the frequency range 10 kHz – 2 MHz have been solved. Morphology of the films was analyzed using a Hitachi S-4800 scanning electron microscope. X-ray diffraction spectra was recorded using a DRON-3 automated diffractometer, using monochromatic CuKα radiation. Capacitance-voltage characteristics were obtained using a B1500A semiconductor analyzer. Dielectric constant and dielectric loss tangent, calculated for capacitance measurements, are changed as follows: for a bias voltage of U = 0 V, the change in ε is 232–214, and tanδ 0.022–0.16, and for a bias voltage of U = 10 V, ε occurs in the range 135–124 and tanδ from 0.02 to 0.1. The obtained frequency dependences of the dielectric constant of BaTiO3 films show a decrease in the dielectric constant in the range of 10 kHz – 2 MHz. It was found that, with a BaTiO3 film thickness of less than 100 nm, a thin-film capacitor with a lower platinum electrode is not always formed, which is probably caused by shunting of the structure.Цель работы заключалась в исследовании диэлектрической проницаемости и тангенса угла диэлектрических потерь пленок BaTiO3 в конденсаторной структуре, сформированной золь-гель методом на подложке Si/TiOx/Pt. Основа данного конденсатора представляет собой четырехслойную пленку ксерогеля титаната бария толщиной около 200 нм. Пленка синтезирована золь-гель методом при температуре окончательного отжига 750 оС. Были решены задачи, связанные с разработкой методики формирования многослойных конденсаторных структур, исследованием морфологического и фазового состава пленки BaTiO3, а также с измерением значений вольт-фарадных характеристик в диапазоне частот 10 кГц – 2МГц. Морфология полученной конденсаторной структуры исследовалась методом растровой электронной микроскопии на установке HITACHI S-4800. Рентгенодифракционные исследования проводились на автоматизированном дифрактометре ДРОН-3 с использованием монохроматического CuKα-излучения. Вольт-фарадные характеристики получены с помощью анализатора полупроводниковых приборов B1500A. Значения диэлектрической проницаемости и тангенса угла диэлектрических потерь, вычисленные для результатов измерений емкости, изменяются следующим образом: при напряжении смещения U = 0 В изменение ε составляет 232–214, и tgδ – 0,022–0,16, а при напряжении смещения U = 10 В изменение ε происходит в диапазоне 135–124 и tgδ от 0,02 до 0,1. Полученные частотные зависимости диэлектрической проницаемости пленок BaTiO3 показывают снижение диэлектрической проницаемости в интервале 10 кГц – 2 МГц. Обнаружено, что при толщине пленки BaTiO3 менее 100 нм тонкопленочный конденсатор с нижним электродом из платины не всегда формируется, что предположительно вызвано шунтированием структуры

Condenser structures based on barium titanate films formed by sol-gel method

Цель работы заключалась в исследовании диэлектрической проницаемости и тангенса угла диэлектрических потерь пленок BaTiO3 в конденсаторной структуре, сформированной золь-гель методом на подложке Si/TiOx/Pt. Основа данного конденсатора представляет собой четырехслойную пленку ксерогеля титаната бария толщиной около 200 нм. Пленка синтезирована золь-гель методом при температуре окончательного отжига 750 оС. Были решены задачи, связанные с разработкой методики формирования многослойных конденсаторных структур, исследованием морфологического и фазового состава пленки BaTiO3, а также с измерением значений вольт-фарадных характеристик в диапазоне частот 10 кГц – 2МГц. Морфология полученной конденсаторной структуры исследовалась методом растровой электронной микроскопии на установке HITACHI S-4800. Рентгенодифракционные исследования проводились на автоматизированном дифрактометре ДРОН-3 с использованием монохроматического CuKα-излучения. Вольт-фарадные характеристики получены с помощью анализатора полупроводниковых приборов B1500A. Значения диэлектрической проницаемости и тангенса угла диэлектрических потерь, вычисленные для результатов измерений емкости, изменяются следующим образом: при напряжении смещения U = 0 В изменение ε составляет 232–214, и tgδ – 0,022–0,16, а при напряжении смещения U = 10 В изменение ε происходит в диапазоне 135–124 и tgδ от 0,02 до 0,1. Полученные частотные зависимости диэлектрической проницаемости пленок BaTiO3 показывают снижение диэлектрической проницаемости в интервале 10 кГц – 2 МГц. Обнаружено, что при толщине пленки BaTiO3 менее 100 нм тонкопленочный конденсатор с нижним электродом из платины не всегда формируется, что предположительно вызвано шунтированием структуры. The objective of the work is investigation the dielectric permittivity and dielectric loss tangent of BaTiO3 films in a capacitor structure formed by sol – gel method on a Si/TiOx/Pt substrate. The basis of this capacitor is a four-layer film of barium titanate xerogel with a thickness of about 200 nm. The film was synthesized by sol-gel method at a final annealing temperature 750 °C. The problems related to the development of method of forming multilayer capacitor structures, the analysis of the morphology and phase composition of BaTiO3 film, and also the measurement of the capacitance-voltage characteristics in the frequency range 10 kHz – 2 MHz have been solved. Morphology of the films was analyzed using a Hitachi S-4800 scanning electron microscope. X-ray diffraction spectra was recorded using a DRON-3 automated diffractometer, using monochromatic CuKα radiation. Capacitance-voltage characteristics were obtained using a B1500A semiconductor analyzer. Dielectric constant and dielectric loss tangent, calculated for capacitance measurements, are changed as follows: for a bias voltage of U = 0 V, the change in ε is 232–214, and tanδ 0.022–0.16, and for a bias voltage of U = 10 V, ε occurs in the range 135–124 and tanδ from 0.02 to 0.1. The obtained frequency dependences of the dielectric constant of BaTiO3 films show a decrease in the dielectric constant in the range of 10 kHz – 2 MHz. It was found that, with a BaTiO3 film thickness of less than 100 nm, a thin-film capacitor with a lower platinum electrode is not always formed, which is probably caused by shunting of the structure

Application of the Method Value of Normally Distributed Settlements to Solving Economic Problems in Agriculture

Bu maqolada normal taqsimlangan bosh tо‘plamning о‘rta qiymatlarini taqqoslash va dispersion tahlil usulining qishloq xо‘jalik sohasidagi iqtisodiy masalalarga qо‘llanilishi kо‘rsatilgan. Shuningdek, normal taqsimlan-gan bosh tо‘plamlarning о‘rtacha qiymatlarini taqqoslash orqali mineral о‘g‘itlarning qaysi biri qishloq xо‘jaligi ekinlari hosildorligi kо‘payishiga qanday ta’sir etishi, bir xil turdagi har xil navli ekinlarning qaysi navlarining hosildorligi yuqori bо‘lishi, yer maydonlariga ekilgan о‘simliklardan olinadigan hosildorlik yer maydonini qanday tartibda shudgor qilishga bog‘liq bо‘lishi aholi ehtiyoji uchun kerak bо‘lgan mahsulotlarni yetishtirishdan avval tajriba asosida ular sifati va miqdori qanday bо‘lishi kabi iqtisodiy masalalarni yechishni kо‘rsatadi

Features of ultrafiltration process engineering calculation in concentration and purification of pectin polysaccharides

In this paper, we propose a mathematical model of the process of changing the productivity of a membrane, both through the formation of a continuous gel layer, and by blocking individual pores. Also, the results of modeling the process of dia- ultrafiltration (DUF) purification of pectin solutions and their concentration by ultrafiltration (UF) using hollow fiber membranes are presented. The effect of periodic washing of the membrane and the process of gelation along the membrane on the productivity of the plant was studied. Thus, the process is characterized by two parameters, and A is the main parameter of the problem, which is the same for all stages, and the second parameter, the ratio (k =F0/F'), characterizes the degree of pore purification with a general cleaning of the membrane surface and is thus one from the characteristics of a single cycle. The valuesof a number of parameters are determined experimentally. It is shown that when the system of differential equations, represented in the normal Cauchy form describing the given technological process, is jointly solved, the productivity of the DUF system can be increased by the frequency of flushing. The conducted experiments demonstrated the advantage of the use of the DUF process in the production of pectin and the features of purification and concentration of apple and sunflower pectins in this process. It is established that the use of DUF causes the introduction of an energy-saving technological process in the production of pectin to produce the target product that meets the required quality and environmental safety of production. The introduction of the proposed methods of DUF and UF into the production of pectin leads to an improvement in the quality and cost of the product

Sol-gel synthesis and transmission of BaTiO₃/SiO₂ multilayer coatings

SOL-GEL METHOD, BARIUM TITANATE, FILTER

CONDENSER STRUCTURES BASED ON BARIUM TITANATE FILMS FORMED BY SOL-GEL METHOD

The objective of the work is investigation the dielectric permittivity and dielectric loss tangent of BaTiO3 films in a capacitor structure formed by sol – gel method on a Si/TiOx/Pt substrate. The basis of this capacitor is a four-layer film of barium titanate xerogel with a thickness of about 200 nm. The film was synthesized by sol-gel method at a final annealing temperature 750 °C. The problems related to the development of method of forming multilayer capacitor structures, the analysis of the morphology and phase composition of BaTiO3 film, and also the measurement of the capacitance-voltage characteristics in the frequency range 10 kHz – 2 MHz have been solved. Morphology of the films was analyzed using a Hitachi S-4800 scanning electron microscope. X-ray diffraction spectra was recorded using a DRON-3 automated diffractometer, using monochromatic CuKα radiation. Capacitance-voltage characteristics were obtained using a B1500A semiconductor analyzer. Dielectric constant and dielectric loss tangent, calculated for capacitance measurements, are changed as follows: for a bias voltage of U = 0 V, the change in ε is 232–214, and tanδ 0.022–0.16, and for a bias voltage of U = 10 V, ε occurs in the range 135–124 and tanδ from 0.02 to 0.1. The obtained frequency dependences of the dielectric constant of BaTiO3 films show a decrease in the dielectric constant in the range of 10 kHz – 2 MHz. It was found that, with a BaTiO3 film thickness of less than 100 nm, a thin-film capacitor with a lower platinum electrode is not always formed, which is probably caused by shunting of the structure