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The monochromator of the Kosmos synchrotron radiation metrology station is described. The results of testing the monochromator in the energy range of 2000-6000 eV using Si (111) crystals are given. A spectral resolution at the level ΔE/E= 10^-4 is obtained. A technique for checking verification spectral purity of the monochromatic radiation is described. It is shown that the monochromator can be used for spectroscopic measurements in the specified subrange.

A technique for designing high-pass terahertz quasioptical filters based on thick (up to 1 mm in thickness) self-supporting copper microstructures of subwave topology. The technique is based on the X-ray lithographic formation of a high-aspect resistive mask made of the SU-8 X-ray resist on a silicon substrate with the use of a tungsten X-ray pattern and subsequent galvanic growing of a copper layer through the resistive mask. The example of a 212-$\mu$m thick structure with a cutoff frequency of 0.42 THz having the topology of hexagonally packed hex-shaped holes is described. The results of the broadband THz characterization of the structure obtained and its electrodynamic analysis are presented.

This paper is a continuation of a series of on the development of the X-ray topo-tomography method using laboratory equipment. The results of a study of the spatial location of a single polygonal dislocation half-loop in a silicon single crystal were obtained for testing the sensitivity of the X-ray TOPO-TOMO diffractometer. A comparison was made with high-resolution experimental data obtained at the European synchrotron radiation facility (ESRF). The experimental procedure and software and hardware for the 3D reconstruction of the investigated single defect - a polygonal dislocation half-loop - are described.

Synchrotron X-ray diffraction study of Ni₃Al single crystals ordered in the L1₂ structure was performed. The ultrafine grained structure resulting from severe plastic deformation was studied. In the initial state, the ordered single crystal is oriented along the compression axis [211]. Along with the ordered phase, there is a small proportion of disordered crystal oriented along the [100] axis. Compression of the samples and subsequent torsion at different angles led to a destruction of the single crystal state of the sample and a changed in the state of the atomic order, up to the disappearance of the L1₂ superstructure.

The sorption process of carbon dioxide by an ionic liquid monomer (ILM) that is 2-methacryloxyethyl diethylammonium chloride, homopolymer based on it, as well as copolymers obtained by copolymerization of the indicated monomer with styrene and methacrylic acid at the molar ratios of 1 : 2 and 1 : 1, respectively, was studied. A relatively high level of absorptive capacity of ILM in comparison with the homopolymer and copolymers based on it was found. The observed relatively high absorptive capacity of СО₂, of the studied ILM is explained by the interaction of the contrarily charged fragment of the monomer molecule. Thus, a decrease in the absorptive capacity of samples in the transition from the monomer to the homopolymer on its base and further to copolymers distinguished by the content of ILM links in the macrochain composition, and consequently, fragments with opposite charges. It was demonstrated that the sorption process of carbon dioxide of the samples studied was reversible and one could reach complete desorption of CO₂ with the recovery of their adsorptive effect. Based on the results obtained, the ILM indicated and its homopolymer and copolymers on its base can be recommended as sorbents for carbon dioxide adsorption.

Sapropels and carbon-mineral composites obtained by thermal treatment of sapropel at various temperatures were studied by X-ray phase analysis (XPA), transmission electron microscopy (TEM), BET and small angle X-ray scattering (SAXS) methods. It was found that the mineral phase in sapropels formed both elongated layered sapropels particles with fractal dimensions and compact large quartz particles. It was demonstrated that heating sapropels at 300°С led to dispersion and stratification of mineral particles in sapropels, but herewith, the organic phase blocked up the pores formed and hinders an increase in the specific surface of the composite obtained. An increase in heating temperature to 600 °С leads to freeing the porous space from the carbon phase and increasing the total specific surface. A further increase in heating temperature to 900 °С gives partial sintering of the mineral phase and transitioning from fractal volumetric structures to surface ones, herewith, the value of the specific surface of composition materials almost does not change.

It was found that mercury contents in saline soils of Bol’shoye Yarovoye Lake met the average content in solonetz soils of the steppe zone of Altai Territory. Differences between types of soils are explained by the peculiarities of solonetz and solonchak processes. The distribution of mercury in bottom deposits is uneven both along cores on depth of individual wells, and in different wells. The average content of mercury and the value of the Hg/Al ratio in bottom deposits are significantly higher than their values in soils because of local pollution. Low mercury contents and Hg/Al ratios were found in coastal wells only. Factor analysis and pair correlation method detected differences in correlations of mercury between soils and bottom sediments both in granulometric fractions, and the initial samples. Correlation analysis results in the initial samples of soils and bottom sediments give the overall picture of mercury distribution in the sedimentation process. Mercury in soils has positive correlations with the terrigenous component that is its major natural source. A negative correlation with the “carbonate” group (Са, Mg, Sr) and antimony is typical. Mercury in bottom deposits has positive correlations with antimony and manganese, and is bound with the major composition of precipitates indirectly only. These results argue of a change in the deportment of mercury in the sedimentation process, which confirms its local entrance into precipitation from a technogenic source that is accompanied by antimony.

An opportunity for bioremediation of ground water polluted by oil products through a system of observation wells was studied. The activity of bioremediation processes was assessed by a change in the content of nitrogen (ammonia, nitrate, and nitrite) in water, the number of aerobic and anaerobic microorganisms and oil products. Microbial growth was stimulated by the introduction of mineral fertilizers into ground water as sources of N and P. Prior to treatment, the number of ammonifying and hydrocarbon oxidizing microorganisms in water collected from wells at polluted sites did not exceed 10⁵ CFU/mL and 10³–10⁵ CFU/mL, respectively. In response to nutrients feeding that limits the growth, the number of aerobic microorganisms increased by 3–4 orders. The number of ammonifying microorganisms increased to 1.8 × 10⁸ CFU/mL, hydrocarbon oxidizing — 2.3 × 10⁷ CFU/mL. An increase in the concentration of ammonia nitrogen (to the values above 50 mg/L) happened in ground water with delay of 2–6 weeks. Dynamics analysis of the chemical composition of ground water by the data of all wells demonstrated that a concerted fluctuation of the activity of nitrification and denitrification processes proceeded in oil products biodegradation in the active phase, and accordingly, of ammonium and nitrate concentrations. Predicting the chemical composition of ground water using a neural network confirmed the same. The content of oil products in ground water decreased by 65–97 %.

A new gas-phase process of halogen-free dimethyl ether (DME) carbonylation to methyl acetate is a promising eco-pure preparation method of methyl acetate due to excluding methyl iodide, replacing methanol for cheaper raw materials that are DME and the removal of the separation stage of the reaction products of the catalyst and methyl iodide. The work presents studying an opportunity of using promoted by silver or copper as catalysts for this reaction. Catalysts with composition of 1 % Ag/Cs_1.5H_1.5РW₁₂O₄₀, 1 % Cu/Cs_1.5H_1.5РW₁₂O₄₀ и Cs_1.5H_1.5РW₁₂O₄₀ were studied by BET, X-ray phase analysis (XPA), scanning electron microscopy (SEM) and IR spectroscopy of adsorbed pyridine. It was demonstrated that the specific surface of samples was about 60 m²/g, the concentration of strong BrØnsted acid sites (BAS) was found at a level of 130 μmol/g, the phase composition of the promoted samples fully corresponded to the initial Cs_1.5H_1.5РW₁₂O₄₀ sample and represented a mixture of two phases that are heteropolyacids and acid cesium salt. High concentrations of BAS demonstrate superacid character of the resulting catalysts capable of activating a C-O bond in the DME molecule. Trials of the samples under industrial catalysis conditions (pressure of 10 atm, temperature of 200 °С, the composition of the initial mixture of DME/CO = 1 : 10) demonstrated that a 1 % Ag/Cs_1.5H_1.5РW₁₂O₄₀ catalyst exceeded the activity of the initial acid Cs_1.5H_1.5РW₁₂O₄₀ catalyst in 2 times, the selectivity by the target product methyl acetate is 60 %. The use of 1 % Cu/Cs_1.5H_1.5РW₁₂O₄₀ does not lead to a change in the activity of Cs_1.5H_1.5РW₁₂O₄₀, the selectivity reduces to 40 %. The data obtained can serve as a basis for elaboration of a silver-containing highly effective catalyst for eco-pure halogen-free DME carbonylation to methyl acetate.

An approach was disclosed to the development of mathematical models of industrial processes using quantum chemical calculation methods of thermodynamic parameters of target and side reactions in combination with experimental data analysis of the operation of an industrial transalkylation process that is one of the preparation stages of ethylbenzene. A scheme of transformations in the transalkylation process was elaborated, thermodynamic parameters of target and side reactions were determined, a kinetic model was compiled and its parameters defined. Adequacy of a model implemented in the HYSYS medium was tested resulting from comparison with industrial data. Application prospects of the developed mathematical model for the transalkylation process to increase energy and resource efficiency of ethylbenzene production were noted from the viewpoint of an increase in process selectivity and minimization of costs on developing a given quantity of the products.