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Structural changes in the Seymchan meteoritic substance after the experiments on loading with spherically converging shock waves have been studied by optical and electron microscopy. It was noted that shock pressure and temperature increases from the outer part to the center of the loaded balls. In one experiment with shock-wave loading, it was possible to obtain varieties of textures with different degrees of shock and thermal metamorphism. These results prove that the shock wave loading experiment can be successfully applied in modeling space shocks and can be used to experimentally model processes at the small bodies of the solar system. The cooling rates of the melted zone of the shocked octahedral sample was estimated for the crystallization range. [ABSTRACT FROM AUTHOR]

The effect of deposition parameters on the properties of particles of hydroxides and chromium oxides was studied. The effect of the calcining temperature on the properties of chromium oxide particles was considered. [ABSTRACT FROM AUTHOR]

Cd1-xZnxS/SnO2:F/glass (Cd1-xZnxS/FTO) photoelectrodes were prepared via successive ionic layer adsorption and reaction method. The obtained samples were characterized by X-ray diffraction, linear sweep voltammetry and impedance spectroscopy under visible light irradiation (λ=450 nm). The highest value of the photocurrent density was observed over Cd0.8Zn0.2S/FTO and equal to 2.2 mA/cm2, that enhanced the values typical of the sulfide-based systems. It was shown that the most effective systems possessed the small resistivity and high electron lifetime. [ABSTRACT FROM AUTHOR]

Corrosion properties of type 625 alloys (Inconel 625 and Nicrofer 6020) in chloroaluminate melts were investigated in a wide range of temperatures and various exposure time intervals using gravimetric tests and energy- dispersive X-ray spectroscopy of corroded samples surface. It was shown that corrosion processes have electrochemical nature and the increase of temperature up to 650 °C leads to change of corrosion mechanism from gradual etching towards intergranular corrosion. Intergranular destruction is associated with the formation of secondary phases at the grain boundaries of alloys. "Time-temperature-precipitation" diagram was constructed to predict the possible conditions of type 625 alloys application. It was found that Inconel 625 and Nicrofer 6020 alloys can be used in contact with chloaluminate melts at temperatures less than 600 °C. [ABSTRACT FROM AUTHOR]

The Arctic attracts the attention of many countries of the world, as it is rich in hydrocarbons. The polar people are faced with the problem of providing electricity. Traditionally, diesel generators are used in the Arctic, while electricity is costly, and the generators themselves pollute the environment. Many researchers use wind generators and solar power plants. Wind generators do not withstand severe frosts and strong winds. This study is devoted to the problem of choosing the type of solar cells that could work efficiently at low temperatures. [ABSTRACT FROM AUTHOR]

Cellulose has been shown to be a perspective substrate for the photocatalytic hydrogen evolution over CdS- based photocatalyst under visible light irradiation (450 nm). Multiphase photocatalyst was synthesized throw simple two- stage method. Samples obtained were characterized by UV-Vis spectroscopy and XRD techniques. The influence of such reaction parameters as photocatalyst loading, substrate concentration and pH was investigated. The highest hydrogen evolution rate equaled to 0.8 mmol·h-1·gcat−1 with the calculated apparent quantum yield of 1.1 %. [ABSTRACT FROM AUTHOR]

The paper studies the troubles occurring because of poor-quality gas separation at the facilities of its field processing. Modernization of gas separators has been proposed to improve the efficiency of removal of undesirable impurities from gas. It has been shown that the replacement of separation devices will provide an increase in the degree of dropping liquid removal by more than two times, while increasing the productivity of the facility and reducing repair costs. [ABSTRACT FROM AUTHOR]

Evolution of the structure and the phase composition, microhardness, contact modulus of elasticity after quenching, further multi-pass cold rolling with a total reduction ratio of 85 % of the hot-worked rods was studied for Ti- 39Nb-5Zr, Ti-39Nb-5Zr-2Sn, Ti-39Nb-5Zr-2Sn-2Ta alloys (composition in wt. %). [ABSTRACT FROM AUTHOR]

The work focuses on sorption of radium by a thin-layer MnO2−CTA sorbent. The maximal sorption of Ra (≈ 90%) was achieved after one day of sorption. For Ra, decrease of quality of alpha spectrum was observed during sorption that can be explained by its diffusion into MnO2 layer. The average thickness of the sorption layer was determined to be 4.56 μm, whereas the energy loss of 5 MeV α-particles in MnO2 is approximately 270 keV per μm. Optical microphotographs confirmed flat morphology of the sorbent's surface and no morphology changes as a result of sorption. [ABSTRACT FROM AUTHOR]

The work describes studies of oxide ceramics in either pure or doped form by the methods of thermoluminescence (TL) and differential scanning calorimetry (DSC). The possibilities of the DSC method for the processes occurring in a solid phase at various samples states have been characterized. Specific intersection points of the methods mentioned have been found at the selected research object. [ABSTRACT FROM AUTHOR]

Ceramic samples were made from the powders obtained by glycine-nitrate synthesis and ammonia co- precipitation of hydroxides to study their suitability for the use as materials of a dense electrolyte and a porous anode of the SOFC, respectively. Dilatometric measurements of the shrinkage of ceramic samples were performed and sintering temperatures were determined. The temperature of pre-sintering of the anode material was determined. To increase the porosity of the anode material the potato and rice starches were used. [ABSTRACT FROM AUTHOR]

The influence of annealing on the cloudy zone of the Seymchan meteorite was studied. Two fragments were heated up to 700 °C from pallasite and octahedrite parts of the Seymchan meteorite (Pallasite Main Group). Changes in the kamacite, taenite, and plessite structures were identified. [ABSTRACT FROM AUTHOR]

Corrosion resistance of such ceramic materials as BN, Si3N4, YSZ (yttria stabilized zirconia) was studied in fused KCl–LiCl mixtures containing 8 wt. % UCl3. The rate and the mechanism of the corrosion of the materials studied were determined. The processes taking place during the interaction between perspective materials and the melt were investigated. [ABSTRACT FROM AUTHOR]

The studies of organic residues on the outer and inner surfaces of archaeological pottery can provide valuable information about the use of kitchen vessels by ancient people, as well as their lifestyle, diet, and culinary practices. Animal fats of various origins are most commonly found in soot from archaeological pottery. They can survive for long periods of time due to their hydrophobic properties. GC–MS analysis of archaeological pottery (Bozshakol site, Republic of Kazakhstan) showed that organic residues of soot are of animal origin, mainly from adipose tissue (fat) of cows and/ or sheep, but the presence of milk fat residues cannot be ruled out. Judging by the presence of biomarkers for the thermal conversion of fatty acids, ceramic vessels could be used not only for storage, but also for cooking on fire. [ABSTRACT FROM AUTHOR]

In this paper, the effect of high molecular weight oil components on the electret properties (surface potential, electric field strength, and surface charge density) of polyethylene was studied. The optimal amount of introduced filler for improving electret properties was revealed. [ABSTRACT FROM AUTHOR]

Compositions based on the oligomer DER-331, modifier PEF-3A and hardener L-20, and chemoelectrets based on them were studied. It was shown that the conditions of simultaneous curing and polarization affect the electret and strength characteristics of the compositions. The combination of the polarization process with the polymer synthesis process leads to the hardening of the polymer material. [ABSTRACT FROM AUTHOR]

Corona electrets investigated on the basis of polylactic acid with talc and mica. It was found that the best electret properties are obtained by compositions of polylactic acid with 2 and 4% mineral filler. [ABSTRACT FROM AUTHOR]

In this work, the surface of the platinum disk electrode was modified with p–aminobenzoic acid by the method of oxidative electrografting (OEG) and the mechanism was proposed. The density of carboxyl groups immobilized in this way was estimated using differential pulse voltammetry. In addition, the effect of preliminary modification of the electrode surface by carboxylated carbon nanotubes (c–MWCNTs) on the density of carboxyl groups was studied. Modification allowed consequently improving the analytical characteristics of the working electrode. [ABSTRACT FROM AUTHOR]

The titanium oxide (Ti2O3) microcrystals were synthesized by using solid-phase sintering from a mixture of titanium Ti and titanium dioxide TiO2 powders. Subsequently, Ti2O3 nanocrystals were produced by using high-energy milling for 15 to 480 min. The analysis of X-ray diffraction patterns have shown that the crystal structure of Ti2O3 nanocrystals coincides with corundum structure (sp. gr. R 3 ¯ c), the intensity of diffraction reflections of Ti2O3 phase are decreased and broadened owing to essential reducing of crystal size of Ti2O3. [ABSTRACT FROM AUTHOR]

This paper presents the results of studies of the influence of the switchgear on the velocity distribution in the tube space of heat exchange equipment. The efficiency of the thermosiphon distributor application is shown. [ABSTRACT FROM AUTHOR]

We have grown the phase-homogeneous quaternary compound Bi1.1Sb0.9Te2S by the addition of Sb to Bi2Te2S which changed the conductivity from n- to p-type. Far-infrared optical and angle resolved photoemission spectra revealed a wide-band-gap three-dimensional topological insulator phase. The surface electronic spectrum is characterized by the topological surface state with Dirac point located above the valence band. [ABSTRACT FROM AUTHOR]

This paper reports the spectroscopic properties of praseodymium-doped potassium lutetium double phosphates, KLuP2O7:Pr3+(1%). Spectra of photoluminescence (PL), PL excitation, X-ray excited luminescence and pulse cathodoluminescence, thermally stimulated luminescence were measured. KLuP2O7:Pr3+ showed Pr3+ emission connected both with high intensity interconfigurational 4f15d1→4f2 transitions (UV bands in region of 250-320 nm), intraconfigurational 4f2→4f2 transitions (weak lines in vision spectral region) and Stocks defect-related luminescence. Upon both UV intra-center and band-to-band excitation with ionizing radiation, emission spectra of KLuP2O7:Pr3+ are dominated by Pr3+ interconfigurational 4f1 5d1→4f2 radiative transitions. Luminescence decay kinetics measurements established decay time τ ≈ 19 ns at room temperature. The study of thermally stimulated luminescence demonstrates effective light storage. Parameters of charge carriers' traps were calculated: ΔE1 = 1.1 eV (for peak at 352 K) and ΔE2 = 1.3 eV (for peak at 388 K). [ABSTRACT FROM AUTHOR]

Cyclic voltammetry was applied for studying electrochemical behavior of iron, nickel and chromium in melts based on the ternary LiF–NaF–KF eutectic mixture. Solubility of iron(III), nickel(II) and chromium(III) fluorides in FLiNaK was determined. [ABSTRACT FROM AUTHOR]

In this work, we studied the effect of milk proteins on antioxidant properties of coffee extracts of various types by the potentiometric method using the K3[Fe(CN)6] / K4[Fe(CN)6] system as an oxidizing agent model. It was revealed that partial binding of phenolic residues to polar groups of milk protein leads to a decrease in the antioxidant capacity, which reduces the product effectiveness in terms of antioxidant action. [ABSTRACT FROM AUTHOR]

Raman spectroscopy has found widespread use helping to understand structure and composition as related to enamel and dentin chemical resistance, mechanical properties, protein alteration, and tooth diseases. The morphology, chemical composition and structure of enamel are the main factors determining tooth resistance to carious and non-carious lesions. We have investigated the teeth with hypoplasia lesions of different severity as well as eroded and intact teeth. In order to investigate the local structural variations of tooth tissues, we performed hyper-spectral Raman mapping. The results substantiate the structural variations in intact and affected teeth as the degree of bioapatite disorder. The changes observed in the degree of mineralization and their manifestation through the linewidth and peak position of P-0 stretching vibration at 960 cm−1 and C-H stretching vibration at 2940 cm−1 are a sensitive probes of the local structural environment. [ABSTRACT FROM AUTHOR]

Analysis of the literature data on the properties of high-entropy alloys based on the Al-Cr-Mn-Fe system was performed. The results allowed evaluating the prospects for the synthesis of high-entropy alloys in Al-Cr-Mn-Fe-(Ti, Zr, V, Nb, Ta) systems. The results of modeling the Al-Ti-Cr-Mn-Fe alloy by ab initio molecular dynamics showed that the formation of a high-entropy alloy is possible. In this alloy, both in terms of partial pair functions of the radial distribution and analysis of the size of atoms, an ordered solid solution can be formed. After analyzing the data obtained from the calculations, we can assume a high probability of formation of intermetallides Al-Ti, Mn-Ti, Fe-Ti and Fe-Al. [ABSTRACT FROM AUTHOR]

Powders of zirconium oxide stabilized by yttrium were synthesized using the precipitation method in the presence of sulfate ions. The effect of pH precipitation, washing and calcination on the properties of zirconium oxide powders was studied. [ABSTRACT FROM AUTHOR]

Powders of partially stabilized zirconium dioxide by yttrium (7YSZ) were obtained by calcination hydroxide (7YHZ) synthesized by controlled two-jet precipitation (CDJP) at different pH values from chloride, nitrate, or acetate solutions of zirconium with the addition of yttrium. The most spherical, large, narrowly dispersed powders are formed from chloride and nitrate media at pH 5.0 and acetate at pH 8.0, while the most randomly connected aggregates with irregular border were formed in the acetate medium. [ABSTRACT FROM AUTHOR]

Fusion technique was applied for synthesis of scandium oxide reference materials (RMs) to control the content of Fe, Mg, Mn, Y, Zr, Yb, Th, Na, P, Si, Ca and Cu trace elements. The sample to flux ratio was 12.5, the flux was a mixture of lithium tetraborate and lithium metaborate (LiT:LiM = 1:1), the releasing agent was KI in the amount of 0.1 g. Reagents were oxides with a purity higher than 99.9 %. First, a concentrated mixture No. 1 was prepared from analytes oxides and flux with a mass concentration of trace elements 0.1–1.0 wt. % depending on the element. Next, the concentrated mixture No. 1 was diluted with borate flux approximately 10 times yielding in an intermediate mixture No. 2. Finally, the intermediate mixture No. 2 was diluted with borate flux approximately 10 times subsequently getting a dilute mixture No. 3 with a mass concentration of trace elements 0.001–0.01 wt. %. Mixtures Nos. 1, 2 and 3 were employed to create reference materials and provide necessary concentration ranges for the calibration curves. The synthesized RMs are intended to define the composition of scandium oxide with X-ray fluorescence analysis. [ABSTRACT FROM AUTHOR]

The possibility of using Purolite C-160 ion exchange resin for separation of La and Ce by the method of size-exclusion chromatography was studied. The saturation of the resin in NH4+ form should be carried out from sulfuric acid solutions at pH 2.5. The exchange capacity value of the resin at full saturation was 35.82 kg La/m3 and 38.37 kg Ce/m3. The chromatography could be carried out by use of Fe3+ as ion-moderator and EDTA solution as eluent (0.015 M, pH 8.0). [ABSTRACT FROM AUTHOR]

The ability of hydrated zirconia oxide powders to remove phosphates from water was studied. The experimental data fitted well with the Langmuir model isotherm. Theoretical maximum adsorption capacity for P was estimated to be 36.3 mg/g. This adsorption capacity was compared with other similar materials. [ABSTRACT FROM AUTHOR]

Reduction of ytterbium, samarium and europium trichlorides to dichlorides was studied in NaCl–KCl–CsCl eutectic and NaCl–KCl equimolar mixture based melts at 823–1123 K employing high temperature spectroelectrochemistry. Electronic absorption spectra of solutions of Yb(II), Sm(II) and Eu(II) chloro species in these melts were recorded. [ABSTRACT FROM AUTHOR]

Sorption of cesium-137 by natural silicate rocks under batch conditions was studied. The regularities of separation of cesium micro quantities from aqueous solutions were studied as a dependence on time of phases contact. Kinetic dependences of cesium-137 sorption from natural waters were obtained. Isotherms of cesium sorption by the silicate rocks are presented. Numeric parameters of the process of cesium sorption indicated the possibility of using silicate rocks for decontamination of drinking waters from radioactive cesium. [ABSTRACT FROM AUTHOR]

Electronic absorption spectroscopy was used to assess palladium speciation in fused alkali chlorides. Electronic absorption spectra of palladium (II) chloro-ions were recorded in molten LiCl–KCl–CsCl eutectic mixture at 300–800 °C. Experimental spectra were resolved into individual bands for more accurate determination of the energy of electronic transitions. Increasing temperature resulted in decreasing absorption and ligand field splitting parameter Δ. [ABSTRACT FROM AUTHOR]

Kinetic of sorption of Sc, Zr, Th, Fe, Ti, Al from hydrolysis acid by phosphorus-containing ampholyte Lewatit TP 260 was investigated. Results of the experiments by the limited-volume method and the method and interruption showed that sorption of Th, Fe, Al took place in the intra-diffusion mode (gel kinetic) and sorption of Sc, Ti, Zr took place in mixed-diffusion mode. [ABSTRACT FROM AUTHOR]

The effect of ammonium nitrate concentration in the initial metal solution on the thermal stability of cerium-zirconium solid solutions was studied. In addition, a comparison was also carried out among our "best" sample and a commercially available solid solution sample of a similar composition. [ABSTRACT FROM AUTHOR]

The possibility of chromium(VI) removing from water by adsorption on mechanically activated rutile was demonstrated. Degree of adsorption of the pollutant was studied as a function of pH, sorbent load, time, solution composition, and also when the aqueous solution was illuminated with various radiation sources. [ABSTRACT FROM AUTHOR]

X-ray fluorescence is a convenient method for the quantitative analysis of antimony sulfide ores. A technique for preparing samples of antimony ores for analysis by high-temperature oxidation of samples in air has been developed and described. This approach makes it relatively easy to synthesize samples for calibration based on a mixture of analyte oxides. [ABSTRACT FROM AUTHOR]

Rubidium and cesium uranates of various composition (M4UO5, M2UO4, M2U2O7 and M2U3O10, M = Cs, Rb) were prepared by reacting triuranium octaoxide with the corresponding alkali metal carbonates. The infrared spectra of the uranates were recorded in the temperature range of 25–700 °C. [ABSTRACT FROM AUTHOR]

This article presents the results of a theoretical study of the possibility of boundary modification of boronitride nanotubes by a functional amine group (-NH2), as well as the interaction of the resulting BNT-NH2 system with potassium, lithium and sodium atoms to create a highly sensitive sensor having sensory activity with respect to alkali metal atoms. [ABSTRACT FROM AUTHOR]

In this research determination of anions SO42–, NO3−, PO43–, Cl− in FLiNaK using capillary electrophoresis was studied. To reduce the effect of the fluoride ion, precipitation using calcium chromate and an electrokinetic input method were used. The content of sulfate and chloride ions in the triple salt was determined. [ABSTRACT FROM AUTHOR]

Solubility of neodymium oxide was determined in molten salt systems based on CaF2–BaF2 (50 mol. %), CaCl2–CaF2 (20 mol. %), CaCl2–CaF2 (75 mol. %), BaCl2–BaF2 (15 mol. %), BaCl2–BaF2 (73 mol. %) and NaCl–NaF (34 mol. %) mixtures at 700–1400 °C. Temperature dependencies of the solubility were calculated. Maximum solubility was observed CaF2–BaF2 (50 mol. %) and CaCl2–CaF2 (75 mol. %) based melts. [ABSTRACT FROM AUTHOR]

Applicability of diffuse reflectance FTIR spectroscopy method was investigated for semi-quantitative determination of oxygen containing impurities in potassium chloroaluminate KAlCl4. The developed method allows to determine the oxygen associated with a OH-group when the analyzed object holding in air. [ABSTRACT FROM AUTHOR]

This work focuses on the study of uranium electrodeposition in the method of alpha spectrometric analysis of uranium isotopic ratio. It was determined that the volume of electrolyte and addition of eluting solution weakly affects the degree of uranium deposition. Optimal time of uranium electrodeposition onto a stainless steel disk was found to be 30 – 40 minutes. The optimal volume of the sample aliquot of uranium leach liquor should contain 250 – 500 µg of uranium that will provide good energy resolution of the alpha source. [ABSTRACT FROM AUTHOR]

The work presents the study and development of the joint processing of ladle furnace and electric arc furnace slag with no waste left. The experimental results proved that slag could be utilized jointly. The study revealed the chemical compositions of slag, which allow the effective utilization. The products of this utilization are cast iron and Portland clinker without any residue left. Final products meet the requirements of normative documents. The study also presents the operations for joint processing. [ABSTRACT FROM AUTHOR]

The task of on-line determination of the leakage occurrence moment of the main pipeline wall and its linear coordinate requires improvement of methods and diagnostic tools, which makes it certainly urgent. There is a number of advantages of acoustic diagnostic method within the framework of the task. The paper deals with development the method by application of electrodynamic analogies based on the classical theory of electric circuits. The paper gives a further advancement of the known approach to the electrodynamic modeling of the pipeline with leakage by the methods of the four-pole network theory with the view of obtaining quantitative estimates of the model. Results of experimental researches show that the obtained amplitude-phase coordinate characteristics can serve as an effective method for diagnosing the state of any dynamic system, including a pipeline with leakage. [ABSTRACT FROM AUTHOR]

Physical and chemical properties of Ti-Al-(Nb, Ta, V) alloys obtained by joint aluminothermic reduction of metals from the oxides were studied. It was found that an increase in temperature from 1500 to 1625 °C contributed to a linear decrease in the density and surface tension of the alloys. Increasing concentration of Nb, Ta and V to 3.5 mol. % affected the increase in the values of these properties. [ABSTRACT FROM AUTHOR]

Leaching scandium from red mud using succinic acid as a leaching agent was investigated. The experimentswere carried out by mixing red mud with a solution of succinic acid. To improve scandium extraction rate, various methods of red mud processing were performed: preliminarygrinding, microwave heating, temperaturetreatment. The highest degree of extraction of Sc was 45 %. [ABSTRACT FROM AUTHOR]

Amorphous silica can be prepared from industrial waste, such as wet magnetic separation tailings of titanium magnetite ore beneficiation and red mud from the Bayer processing of bauxite into alumina, with silicon content of 10 to 50% in them. We considered fluoridation of polycomponent technogenic materials by solid-phase synthesis with the change of process temperature and a hydrochemical synthesis by NH4HF2 solution. The variation of the sintering process temperature range allows obtaining the ammonium fluorometallates or simple fluorides. It was found that nanosized silica obtained from waste has a high purity (≥99%), specific surface area (240-300 m2/g), pore volume (0.25-0.28 cm3/g). The experiments demonstrated that to produce amorphous silicon dioxide from waste, a solution should be with an ammonium hexafluorosilicate concentration 80-100 g/l and the process of ammonia hydrolysis should be carried out at 40-80 °C. An efficient method for extraction of SiO2 with a small particle size and high hydrophobic properties from waste is proposed, which currently does not have an appropriate application and is stored on disposal area. Such amorphous silica can be used in the production of catalysts, ceramics, heat- and fire-resistant rubber, and silicon fluoride complexes. [ABSTRACT FROM AUTHOR]

To determine the feasibility of processing the uranium-containing wastes in order to uranium recovery, several studies of solid radioactive wastes were carried out. It was found, that calcium sulfate (41-60 %), calcium carbonate (21-39 %), calcium fluoride (10-14 %) and silicon dioxide (1-7 %) were main compounds of the sludge. The mass content of uranium in the sludge was 0.11 wt. %, while uranium containing compounds was not detected by X-ray powder diffraction. The isotopic composition of uranium in the sludge corresponded to the isotopic composition of natural uranium, the specific alpha and beta activity amounted to 42 kBq kg-1 and 44 kBq kg−1, respectively. [ABSTRACT FROM AUTHOR]