Abstract The features of the electronic structure of Matrimid, which are important for assessing the sorption ability of the specified polymer as a membrane material, are considered. Using the density functional theory, the charge states of sorption centers in the Matrimid are calculated. The most probable polymer atoms responsible for nonvalent interactions of polar molecules of gases or liquids when

Abstract In this study, the variation of the resistivity of Al85Y9Ni6 metallic glass produced by melt-spinning method was investigated and formulated. DSC results demonstrate three crystallization peaks and resistivity measurements support this result. The electrical resistivity measurements were carried out in the temperature range 300–877 K by the four-point method. The greatest reduction in resistivity

Abstract In this paper, we present a new cubic boron nitride synthesis method via introduction of highly reactive nitrogen and boron atoms generated from chemical reactions as the raw materials of cubic boron nitride, so the system pressure and temperature are reduced significantly compared with the traditional phase transformation method at super high-pressure and high-temperature, and then the production

Abstract Xerogels in the ZrO2–Y2O3–CeO2 system are obtained by coprecipitation. The influence of the synthesis method on the acid-base xerogel surface properties are studied. The sinuous dependence of the Lewis and Brønsted site content on the particle surface on the conditioning time of precipitates in the mother liquor and the presence of subsequent low-temperature processing is established. The

Abstract— Bismuth-containing composite materials (BCMs) are synthesized by the impregnation of matrices of thermally modified high-silica porous glasses (PGs) in aqueous solutions of bismuth nitrate (0.5 M) followed by heat treatment in a wide temperature range from 50 to 875°C. The obtained materials are studied by the infrared spectroscopy method in the frequency range 1100–400 cm–1 depending on

Abstract— The data concerning the studies of solutions, oxide glass, and natural polymers are presented as a result of processing the vibrational and electron spectra by the methods of mathematical statistics. It is shown that based on the proposed concept, the information about stoichiometry and concentrations of the molecular groups of the constant stoichiometry formed in the glass can be obtained

Abstract The effect of crystal nuclei formed during the production of glass on the kinetics of nucleation of crystals in it at temperatures below the glass transition temperature is studied. A glass composition of 22.4Na2O ⋅ 28.0CaO ⋅ 49.6SiO2 (mol %) is studied (glass transition temperature 540°C). Using the development method, the dependence of the number of nucleated crystals on the heat treatment

Abstract The work is devoted to studying the influence of synthesis conditions on the hydrothermal crystallization of zeolite nanoparticles with a Beta structure and studying their properties. The experimentally optimal conditions for the preparation of Beta zeolite nanoparticles of various sizes are determined by varying the temperature and time parameters of the process. The synthesized samples are

Abstract The work is devoted to studying the parameters of the porous structure and catalytic activity of materials containing zeolites of the structural types ZSM-5 and BEA and aluminum hydroxides from various manufacturers. It is shown that it is possible to purposefully control the parameters of the porous structure of zeolite compositions, which serve as the basis for the catalysts of many processes

Abstract The 61Cu (61Ni) emission Mössbauer spectra of high-temperature superconducting ceramics are measured, as well as a number of dielectric and antiferromagnetic cupric metal oxides, which are structural analogues of high-temperature superconductors. The 61Ni nuclei quadrupole coupling constants are determined and their linear correlations are established with the calculated values of the lattice

Abstract A comparative study of the kinetics of massive bulk crystallization of As2Se3, As1.9Se3, and As2.1Se3 bulk glasses at 240°C is performed using the Kolmogorov–Avrami model. A theoretical analysis of the experimental dependences of the linear growth rate of As2Se3 crystals on temperature and viscosity of the As2Se3 glass is performed. It is shown that the dislocation growth of crystals in the

Abstract Glasses with compositions 20BaO · 10Bi2O3 · (70 – x)B2O3 · xV2O5 with x = 0, 0.2, 0.4, 0.6, 0.8 and 1 mol % were prepared by melt quenching technique. The amorphous nature was established by X-ray diffraction studies. Fourier transform infrared studies carried out for samples and it exhibit absorption bands for oxides in various structural units. Physical parameters viz., density, molar volume

Abstract— A combinatory topological analysis and simulation of the self-assembly of the crystal structure of Ca11Hg54–hP65 (a = b = 17.114 Å, c = 10.442 Å, hexagonal group P-6) are performed by computer methods (ToposPro software package). A total of 184 variants of the cluster representation of the 3D atomic lattice with a number of structural units of 3–7 are established. The polyhedral clusters

Abstract Results of turbidimetry study of aggregate stability of binary SiO2–ZrО2 sol and its components in 10–3–10–1 M KCl solutions at рН 3.4 when ZrO2 particles have a high positive charge and SiO2 particles are slightly (close to zero) negatively charged are presented. The ratio of numerical concentrations of sol particles ZrO2 to SiO2 was 7.8 : 1. It was found that in binary SiO2–ZrО2 sol both

Abstract The effect of laser radiation on the surface and volume of natural quartz of the Bural-Sardyk deposit (East Sayan, Buryatia) is studied. The influence of the main parameters of laser radiation with a wavelength of 213 nm (prefix NWR-213) and the properties of the sample on the results of elemental mass spectrometric analysis with inductively coupled plasma are established. The features of

Abstract A combinatory-topological analysis and simulation of the self-assembly of the crystal structure of (Sr2Au6)(Ga3)–hR66 (spatial group R-3c, a = b = 8.419, c = 21.911 Å, V = 1345Å3) is performed by the computer methods (ToposPro software package). A new geometric type of the polyhedral precursor cluster K8 = 0@8(Sr2Au6), where Au6 rings are the base and Sr atoms serve as peaks, is established

Abstract In the present contribution, we deal with the question whether the equilibrium of the silica/water reaction shifts under tensile stresses to an increased or reduced hydroxyl concentration or, equivalently, which sign the reaction volume shows. From our analysis on the basis of the Le Chatelier–Braun Theorem, it can be concluded that the equilibrium constant of the water/silica reaction is

Abstract An electroactive material of a pseudocapacitor (PC) electrode based on highly dispersed MnO2 powders and its composites are obtained. The composition and surface morphology of these materials are investigated. The conditions for manufacturing electroactive paste from synthesized powders are determined. Technological methods are developed for the manufacture of the PC electrodes consisting

Abstract A novel and effective method for synthesis of mesoporous silica is reported in this paper. The method was based on the use of the tetraethoxysilane (TEOS) as precursor and the layered liquid crystals (LCs) as templates formed by cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS). The range of the LCs was determined by exploring the phase behavior of the system with different

Abstract— Based on the Raman spectra and quantum chemical simulation, the structure of the [Pb(thio)2(mono-ac)2] coordination compound of lead acetate with thiocarbamide is found. It is shown that use of this compound in a water solution for the precipitation of polycrystalline films by aerosol spray pyrolysis (ASP) leads to the formation of a single-phase film of lead sulfide without impurity phases