Condensed Matter and Interphases

The goal of this work was to study phase relations in the ternary Si–Sn–As system: to establish cross sections, to construct a scheme of phase equilibria, and to identify the temperature of non-variant transformations. Ternary alloys were obtained through direct synthesis from simple substances and subjected to long-term solid-phase annealing. Alloys of four polythermal sections of the Si–Sn–As system were examined using X-ray phase and differential thermal analysis. The results of X-ray powder diffraction allowed establishing that the phase subsolidus demarcations was performed by the SnAs–SiAs2, SnAs–SiAs, Sn4As3–SiAs, and Sn4As3–Si sections. As a result of the experiment, taking into account the theoretical analysis, we suggested a scheme of phase equilibria in the system that involved the implementation of eutectic and four peritectic invariant equilibria, and we used differential thermal analysis to determine the temperature of these four-phase transformations. It was found that extended solid solutions were not formed in the system, and only a substitutional solid solution at least 3 mol % wide was formed based along the SnAs–SiAs2 section based on tin monoarsenide

Tatiana P. Sushkova

Galina V. Semenova

Elena Yu. Proskurina

Конденсированные среды и межфазные границы

Phase relations in the Si–Sn–As system

Si–Sn–As体系中的相位关系

Phase equilibria in the Ag2S–Ag8SiS6–Ag8GeS6 system were studied using differential thermal analysis and powder X-ray diffraction technique. Boundary section Ag8SiS6 – Ag8GeS6, liquidus surface projection, an isothermal section of the phase diagram at 300 K, and some polythermal sections of the studied system were constructed. The formation of continuous series of solid solutions between both crystalline modifications of the starting compounds was determined in the Ag8SiS6–Ag8GeS6 system. The liquidus surface of the Ag2S–Ag8SiS6–Ag8GeS6 system consists of two fields corresponding to the primary crystallization of the high-temperature modifications of the HT-Ag8Si1-xGexS6 and HTAg 2S phases. Lattice parameters for both modification of solid solutions were calculated based on powder X-ray diffraction data. The concentration dependence of lattice parameters obeys Vegard’s rule. The obtained new phases are of interest as environmentally safe materials with thermoelectric properties and mixed ionelectron conductivity

Garay M. Ashirov

Kamala N. Babanly

Leyla F. Mashadiyeva

Yusif A. Yusibov

Mahammad B. Babanly

Phase equilibra in the Ag2S–Ag8GeS6–Ag8SiS6 system and some properties of solid solutions

Ag2S–Ag8GeS6–Ag8SiS6体系中的相平衡及固溶体的一些性质

Silicon compounds have a wide range of electrical properties. In particular, the possibility of creating thermoelectric converters based on them looks extremely attractive. The use of most silicides as thermoelectrics today is limited by their low efficiency. The development of approaches consisting in the creation of low-dimensional structures using non-equilibrium formation methods is one of the priority directions for improving the properties of thermoelectric generators. Determination of the effect of technological regimes on the structure, phase-chemical composition and thermoelectric properties of metal-silicide structures is a key task, the solution of which will allow creating highly efficient thermoelectric generators based on them. Thin-film structures with a layer thickness of ~50 nm formed at different growth temperatures by pulsed laser deposition on two types of substrates: sapphire and gallium arsenide coated with an Al2O3 nanolayer were studied in this work. On the formed samples, a chemical analysis and a study of the phase composition were performed. Chemical analysis was carried out by X-ray photoelectron spectroscopy with the chemical composition depth profiling. The phase composition was studied by Raman spectroscopy. In addition, analysis of the elements in the films was carried out by X-ray spectral microanalysis based on a scanning electron microscope. To determine the thermoelectric properties of the formed thin-film structures, the temperature dependences of the Seebeck coefficient and the electrical conductivity coefficient were recorded. The dependence of the thermoelectric characteristics of iron silicide films on the phase composition is analyzed. In particular, measurements of the thermoelectric properties of FeSix thin-film structures registered the manifestation of a strong thermoelectric effect in layers with the maximum number of chemical bonds between iron and silicon. The parameters of the growth process at which the most effective formation of iron-silicon chemical bonds is achieved were determined using the method of X-ray photoelectron spectroscopy. Line shifts from the beta phase of iron disilicide were found in the Raman spectra and the reasons for their appearance were proposed

Dmitri E. Nikolichev

Ruslan N. Kriukov

Alexey V. Nezhdanov

Anton V. Zdoroveyshchev

Yuri M. Kuznetsov

Daniil A. Zdoroveyshchev

Valery P. Lesnikov

Michael V. Dorokhin

Polina B. Demina

Alexey A. Skrylev

Composition and thermoelectric properties of structures based on iron silicide grown by pulse laser deposition

脉冲激光沉积生长的铁硅化物基结构的组成和热电性能

The article studies the molecular composition of dental biofilm in healthy people and patients with multiple caries lesions during several stages of exogenous and endogenous preventive measures. The observed changes in the IR spectra registered during different stages of the experiment indicate a lack of balance between demineralisation and mineralisation of hard tissues resulting from different absorption mechanisms of agents applied exogenously and endogenously. All the observed changes result from the difference in the microbiota in healthy patients and patients with caries, as well as the difference in the microbiota caused by the impact of preventive agents on biofilm

Pavel V. Seredin

Dmitry L. Goloshchapov

Vladimir M. Kashkarov

Nikita S. Buylov

Yury A. Ippolitov

Ivan Yu. Ippolitov

Jitraporn (Pimm) Vongsvivut

Features of the molecular composition of dental biofilm in patients depending on the degree of caries and the method of its prevention: synchrotron FTIR spectroscopic studies

牙科生物膜分子组成特征：根据龋齿程度和预防方法的同步辐射FTIR光谱研究

The process of atomic hydrogen penetration into the metal phase is complicated by the phase-boundary transition from the liquid and/or gas phase. That is why the cleanliness of metal and alloy surfaces is of particular importance. The purpose of this work was to determine the effect of surface pretreatment using photon pulses, ultrasound, and potential cycling on the parameters of hydrogen permeability for 48Cu52Pd metal cold-rolled membranes. The study was focused on a foil of copper-palladium homogeneous alloy with 48 at. % Cu and 52 at. % Pd composition. The studied samples were obtained by cold rolling and their thickness were 10 and 16 μm. Surface pretreatment included rinsing in acetone, using ultrasound, pulsed photon treatment, and quadruple potential cycling over a wide range of potentials. Electrochemical studies included cyclic voltammetry and cathode-anodic chronoamperometry in a deaerated 0.1 M H2SO4 solution. Hydrogen permeability was calculated using mathematical models for samples of finite and semi-infinite thickness. It was found that the surface treatment of a 48Cu52Pd foil with photon pulses leads to both an increase in the ionisation rate of atomic hydrogen and an increase in the roughness of the foil surface. The diffusion coefficient of atomic hydrogen does not depend on the method of surface pretreatment with ultrasound and photon pulses. The extraction rate constant for the extraction of the atomic hydrogen after photon treatment increases, which facilitates the processes of both H introduction and ionisation due to the release of active centres of the surface. Electrochemical cleaning of the surface during the quadruple potential cycling contributes to the growth of the extraction rate constant for the extraction of atomic hydrogen

Natalia B. Morozova

Lidiya E. Sidyakina

Alexey I. Dontsov

Alexander V. Vvedenskii

Hydrogen permeability of 48Cu52Pd cold-rolled alloy foil and different methods of its surface pretreatment

48Cu52Pd冷轧合金箔的氢渗透性及其不同表面预处理方法

The materials of the tin-oxygen system and thin-film structures based on them are modern and actual for the creation of a wide range of electronic devices, for example, resistive gas sensors of high sensitivity and short response time with low energy consumption and high manufacturability. An important direction in the study of such materials and structures is the control of properties with variations in technological formation regimes. Information on the composition, local atomic and electronic structure of thin layers of the tin-oxygen system with varying approaches to their production is in demand. The work is devoted to the study of the electronic structure of thin layers of tin oxides obtained by modern methods of molecular beam epitaxy and magnetron sputtering. A study of the local partial density of electronic states in the conduction band by X-ray absorption near edge structure spectroscopy of tin and oxygen has been carried out. The data were obtained using high-intensity synchrotron radiation, which allows varying the monochromatized radiation quantum energy without loss in intensity, that is necessary to obtain high-resolution X-ray spectral data. It is shown that the composition, local atomic surrounding, electronic spectrum and their features depend on the technology of formation and storage conditions of the studied structures. Synchrotron X-ray spectroscopy data show the presence of intermediate oxides of the tin-oxygen system in the studied materials after prolonged storage in laboratory conditions. The data obtained indicate the possibility of controlled variation in the composition, local atomic surrounding and electronic spectrum of thin-film structures of tin oxides of small thickness. The results of the work can be used in the formation and subsequent modification of thin and ultrathin layers of tin oxides by magnetron sputtering and molecular beam epitaxy, as well as in their further application as active layers of microelectronics devices

Olga A. Chuvenkova

Nikolai I. Boikov

Stanislav V. Ryabtsev

Elena V. Parinova

Ratibor G. Chumakov

Alexei M. Lebedev

Dmitry Smirnov

Anna Makarova

Sofia S. Titova

Kirill A. Fateev

Sergey Y. Tirischev

Electronic structure and composition of tin oxide thin epitaxial and magnetron layers according to synchrotron XANES studies

同步辐射XANES研究锡氧化物薄外延层和磁控层的电子结构与成分

Tungsten antimony acids (TAA) with the composition H(2)Sb(2)WXO6·nH2O (0 &lt; x ≤ 1.45; 0 &lt; n ≤ 2.0) have been synthesized by hydrolysis of antimony trichloride pre-oxidized with nitric acid in the presence of varying amounts of Na2WO4. To obtain TAA protonated forms, the samples were kept in a 96% solution of sulphuric acid, the precipitate was washed until reaction became neutral and dried in air. The amount of tungsten, antimony, and silver ions in TAA was determined using energy dispersive analysis. Changes in structural parameters upon doping of AA with tungsten ions were studied using a Bruker D8 ADVANCE X-ray diffractometer (CuKa1-radiation). The number of oxonium ions in TAA was determined by the substitutionof these ions by silver ions in equivalent amounts (Ag+-TAA forms). All obtained TAA samples and Ag+ TAA forms had a pyrochlore-type structure, space group symmetry Fd3m. Refinement of the arrangement of atoms in the structure using the Rietveld method showed that tungsten ions replace antimony ions and are statistically located in 16c, oxygen anions in 48f, and oxonium ions and water molecules in 16d and 8b positions, respectively. When tungsten ions were introduced into samples, the structural parameters of the resulting phases changed. There was a decrease in the unit cell parameter and the distance between antimony ions and oxygen anions, while an increase in the distance between oxonium ions and oxygen anions located in 48f positions was observed. This allowed the removal of a proton from oxonium molecules and its transport via a system of hydrogen bonds formed by water molecules

Pyotr V. Timushkov

Vladimir A. Burmistrov

Maxim N. Ulyanov

Victor N. Semenov

Composition and structure of tungsten antimony acid

钨锑酸的组成与结构

Although widely used in the textile industry, methyl orange is considered one of the most toxic dyes, which have negative impacts on the aquatic environment and needs to be removed from water bodies. Hence, the present paper reports the synthesis of new floating photo-Fenton catalysts based on the immobilization of Fe2O3 nanoparticles on the surface of Luffa sponges for the oxalate-induced-degradation of methyl orange. The floating catalytic sponges were prepared through a simple precipitation method followed by a reflux heating process and then characterized by field emission scanning electron microscopy, X-ray diffraction, atomic absorption spectrometry, and nitrogen adsorption-desorption experiments. According to the experimental results, methyl orange was effectively degraded over our floating catalytic sponges underlight illumination at near neutral pH. The catalytic activity was also found to be enhanced with the increase in crystallinity of Fe2O3 nanoparticles, which can be achieved by the reflux heating. Besides, owing to the floating feature, these sponges are easily separated from the solution, thereby not forming a secondary source of pollution for water

Nhu Le Thi Quynh

Trang Ly Thi Quynh

Nguyen Anh Tien

Nguyen Quoc Thiet

Tsai De-Hao

Le Tien Khoa

Simple synthesis of floating Fe2O3/Luffa catalysts for the photo-Fenton degradation of methyl orange at near neutral pH

近中性pH下用于甲基橙光芬顿降解的漂浮Fe2O3/丝瓜催化剂的简易合成

Spontaneous photomagnetoelectric effect in ferromagnetic GaMnAs epitaxial layers has been investigated. The goal of this work is to study the temperature dependence of the spontaneous PME effect, determined along [110] and [110] crystal axes. GaMnAs layers with Mn concentration of 2.9 atomic percent studied in this paper were grown by low-temperature molecular beam epitaxy on semi-insulating GaAs (001) substrate. It was shown that below Curie temperature in the illuminated GaMnAs epilayers a transverse voltage (photo-EMF) was observed. This photo-EMF is associated with the photomagnetoelectric effect resulting from the separation the photogenerated carriers by the intrinsic magnetic field of the semiconductor matrixin ferromagnetic state. The temperature dependence of intrinsic photomagnetoelectric effect in GaMnAs epilayer was determined along [110] and [110] crystallographic axes. It was found that the photo-EMF measured along [110] crystal axis exhibits a maximum at temperatures of 35–40 K, while the photo-EMF measured along [110] axis increases monotonically with temperature decay. It was shown that the non-monotonous temperature dependence of the photomagnetoelectric effect along [110] axis can arise due to the reorientation of the easy axis of the sample with decreasing temperature

Pavel B. Parchinskiy

Alisa S. Gazizulina

Rafael A. Nusretov

Spontaneous photomagnetoelectric effect in ferromagnetic GaMnAs epitaxial layers

铁磁性GaMnAs外延层中的自发电磁光电效应

The aim of the work is to study the influence of the 3-D printing process with the Hercules Original printer by sequentially applying polymer layers using the FDM (Fused Deposition Modeling) method on the microstructural and hydrophilic properties of polyethylene terephthalate glycol (PETG) samples with different printing patterns. X-ray phase analysis revealed the presence of a greater ordering of amorphous PETG polymer chains in printed samples, which occurs during thermal and mechanical impact on the initial filamentous sample during 3D printing. This manifests itself in the increase of relative intensity for the main diffraction peak of the amorphous PETG polymer by an order of magnitude for all of the samples with five different print patterns. At the same time, IR spectroscopy data revealed the preservation of all intrastructural chemical bonds of the polymer both in the original thread and in printed samples. Close contact angles of about q≈50° for all printed samples, which is much smaller than the right angle q=90°, show that the surfaces of all five printed PETG samples with different patterns are hydrophilic

Alexander S. Lenshin

Vera E. Frolova

Sergey A. Ivkov

Evelina P. Domashevskaya

Microstructural and hydrophilic properties of polyethylene terephthalate glycol polymer samples with different 3D printing patterns

不同3D打印图案聚对苯二甲酸乙二醇酯聚合物样品的微观结构和亲水性

涉及主题	化学物理材料科学有机化学量子力学冶金工程类复合材料计算机科学化学工程纳米技术生物结晶学
出版信息	出版商: Voronezh State University，出版周期: ，期刊类型: journal，开源期刊: 是
基本数据	创刊年份: 2019，原创研究文献占比: 0.00%，自引率:N.A.， Gold OA占比: 0.00%
平均审稿周期	网友分享经验：8 Weeks

Condensed Matter and Interphases

期刊引文格式

有 1 位以上作者的期刊

有 2 位作者的期刊

有 3 位作者的期刊

有 5 位以上作者的期刊

书籍引用格式

学位论文引用格式

网页引用格式

专利引用格式

手工熬夜修改参考文献？研飞自动匹配期刊，一键轻松成稿，支持 Word/WPS

投稿经验分享