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A review of the work carried out jointly by specialists from UrFU and JSC «Institute of Nuclear Materials» on the experimental design studies of the composition of combined radiation protection is presented. The analysis of the results of designing the composition of homogeneous radiation protective materials (RPM) and their potential in the implementation of the optimization principle in the planning of radiation hazardous work using the example of conditioning liquid radioactive waste during ion selective cleaning is carried out. [ABSTRACT FROM AUTHOR]

Three types of halloysite samples were studied. The ionizing radiation induce in halloysite two types of defects demonstrating electron paramagnetic resonance (EPR) signals with g-factors 2.0 3 and 2.032. Purification of samples rises their EPR responsibility to irradiation. Radiation defects also demonstrate thermoluminescence (TL) in two different wavelength ranges. [ABSTRACT FROM AUTHOR]

The aim of this work is to calculate the dependences of the complex dielectric permeability and complex refractive index on frequency for a composite material with metal nanoparticles. A dielectric matrix with randomly distributed gold nanoparticles in it was chosen as a nanocomposite. [ABSTRACT FROM AUTHOR]

The inhalation exposure to dust in the urban environment for adult and child is very important due to health issues. The radionuclides Ra-226 and Th-232 were measured in the samples of urban surface deposited sediments. The average concentrations of Ra-226 and Th-232 in dust are 20.8 and 15.3 Bq kg-1, respectively. The effective dose is estimated depending on the daily activity and air dust concentration for the adult and child. The results show that the total effective dose received during 70 years by adult without outdoor activity is 0.74 µSv under exposure to air dust concentration 1x10-4 g/m3, which is typical for the city of Ekaterinburg. Critical scenario of exposure of an adult person to radioactive material in particulate matter in the air including such daily activities as training, bicycle driving and work in urban environment results in the total effective dose 17.8 µSv during 70 years at air dust concentration equal to the diurnal Maximum Permissible Limit (1.5x10-4 g/m3). Also, the critical children group can be exposed to radionuclides by inhalation through daily outdoor games, sport activity, training, bicycle etc (8 hours daily during vacation, 4 hours daily during school time, 2000 hours per year from 7 years to 17 years). The total effective dose for critical children group is 2.9 µSv. Thus, the effective doses due to inhalation of natural radioactivity in the dust in city of Ekaterinburg are relatively low in comparison ICRP reference level. [ABSTRACT FROM AUTHOR]

A molecular dynamics simulation of helium diffusion in solid CaF2, SrF2, and BaF2 was carried out using the empirical pair potentials reproducing the experimental strong binding of helium to cations in these crystals. The model diffusion coefficients and activation energies are determined. [ABSTRACT FROM AUTHOR]

Electrochemical behavior of gallium was studied in 3LiCl–2KCl and 6NaCl–9KCl–5CsCl eutectic based melts at 450–650 °C using potentiometry, cyclic voltammetry and cathodic polarization measurements. Mechanism of Ga(III) ions reduction was assessed and electrode potentials of gallium determined. [ABSTRACT FROM AUTHOR]

The evolution of ellipsoidal crystals in a supercooled one-component melt is considered during the intermediate stage of a phase transformation process. The melt supercooling and crystal-volume distribution function are analytically derived using the main contribution to the Laplace-type integral for the melt supercooling. It is shown that the supercooling decreases and the distribution function increases with time as a result of latent heat release by the growing crystals. [ABSTRACT FROM AUTHOR]

Thin films of Cu2ZnSnSe4 (CZTSe) were fabricated by the selenisation of metallic precursors sequentially deposited on Mo coated glass substrates. The surface morphology and cross section, studied by a scanning electron microscope (SEM), reveal densely packed grains with sizes in excess of 1 µm and CZTSe film with a thickness of 1.4 µm. The elemental composition of both the precursors and CZTSe films was measured by an energy dispersive X-ray analyser demonstrated a copper deficiency and zinc excess as well as a near stoichiometric content of Se. A set of 4 as deposited CZTSe films was used to produce solar cells with the structure ZnO/CdS/Cu2ZnSnSe4/Mo/glass. These films were coated with CdS buffer layer using a standard chemical bath deposition after chemical etching using KCN or/and ammonia: film E was not etched, film B was etched in KCN for 2 minutes, film C was etched in KCN for 5 minutes and film D was etched in KCN for 30s and then in ammonia for 5 minutes. Solar cells were then completed by DC-magnetron deposition of ZnO/ZnO:Al transparent front contacts. Finally solar cells with areas of 3x3 mm2 were separated by mechanical scribing. The structural properties of the cells and phase content of the CZTSe layer were examined by x-ray diffraction (XRD). Low intensity reflexes of the secondary phases SnSe and SnSe2 were also present. The bandgaps Eg of the CZTSe layers in the cells, measured by photoluminescence excitation (PLE) at 4.2 K, were found to be of 1.05 eV in all the four cells. This cell also showed the highest FF of 41.1% whereas the best Isc of 46.6 mA/cm2, demonstrated by the D cell. The highest conversion efficiency of 6.2% was obtained for the E cell, produced without any etch, and for the D one after 30 s etch in KCN plus 5 minutes in ammonia. [ABSTRACT FROM AUTHOR]

This paper presents the results of the study of the effect of structural modifications of carbon nanotubes on the surface adsorption of the main elements of the products of the shot of the non-corrosive shock composition of the igniter. Carbon single-layer nanotubes of types «armchair» (6,6), «chiral» (3,6) and «zig-zag» (0,10) have been considered. The calculations are performed in the framework of molecular cluster model using semiempirical PM3 scheme. [ABSTRACT FROM AUTHOR]

In this paper, we given the conditions for ensuring radiation safety of personnel. We described the content and ways of implementing one of the basic principles of radiation safety, the optimization principle. Shown the potential of route optimization in minimizing personnel dose costs when moving and performing work in non-stationary radiation fields. An interpolation algorithm based on the radial basis function method is proposed and implemented for constructing a radiation map of a room. A comparative analysis of the use of various radial basis functions in the problems of nuclear energy is carried out. The results of a computational experiment using the URAN supercomputer and an assessment of the effectiveness of the developed algorithm are presented. [ABSTRACT FROM AUTHOR]

The synthesis of quantum dots (QDs) of direct band gap semiconductor cubic ZnS through modified green chemistry-mediated chemical precipitation reaction is presented. Green chemistry-synthesized ZnS QDs were characterized using X-ray diffraction and dynamic light scattering. UV-Vis absorption spectroscopy (Eg = 3.83.4.3 eV) showed a distinct blue shift than the bulk. An intense and broad photoluminescence band with a maximum at 430 nm was found for samples with high pH of the solution. Zeta potential (up to minus 80 mV) evidently proved the existence of stable ZnS QDs in the water solution. [ABSTRACT FROM AUTHOR]

Knowledge about the occurrence and concentration of radon in environmental samples is essential for monitoring their background levels and their health effects for population. The main aim of this work was to shed more light on 22Rn concentration (Bq/m3), 222Rn exhalation rate, annual effective dose (in doors) and RRLC (%), in Monzogranite, Dokhan Volcanics (Rhyolite, Dacite, Quartz andesite, Andesitic basalt), Syenogranite, Granodiorite, Gabbro and Metabasalt samples collected from Wadi um Huytat area in Central Eastern Desert of Egypt, using Alpha GUARD. The concentrations ranging between 19.67±8.11 to 258.11±63.78 with an average value 95.28±30.72 Bq/m3, from 0.08±0.07 to 1.89±0.49 with an average value 0.66±0.24 mBq/m2s, from 0.187 to 2.453 with an average value 0.905 mSv/y and from 1.017 to 1.253 with an average value 1.089 %, respectively. The three highest values for different basement rocks were found in Syenogranite, Monzogranite and Rhyolite (sample code C22, C19, C17-1,) which have 222Rn concentrations 258.11±63.78, 252.78±62.78 and 220.33±55.78 Bq/m3, respectively. The maximum value of radon concentration in all samples was lower than the national reference level of 300 Bq/m3 recommended in ICRP Publication 126. The obtained results for radon concentrations seems to be acceptable and not concerning a health hazard for the inhabitant. [ABSTRACT FROM AUTHOR]

The features of defects formation in silica implanted by rhenium have been studied. The optical absorption studied samples contains selective bands of 5.1, 5.8, 7.0, and 7.5 eV of oxygen-deficient ODC-type defects. The optical transitions 5.1 and 7.0 eV related to ODC (II) oxygen divacancies, 7.5 eV to the neutral oxygen vacancy (ODC (I)), and the 5.8 eV band to the three-coordinated silicon atom E' center. The photoluminescence spectra were obtained using a fluorescence spectrometer PerkinElmer LS55. We observed a new type of luminescent Re-related centers having the luminescence band at 2.53 eV. The energy transfer from Si ODC to Re-related centers was found. [ABSTRACT FROM AUTHOR]

Polarization of solid (tungsten) and liquid (zinc, gallium–zinc eutectic alloy) was studied in LiCl–KCl–ZrCl4, LiCl–KCl–UCl4, LiCl–KCl–UCl3 and LiCl–KCl–ZrCl4–UCl4 melts. Deposition potentials of zirconium and uranium were determined. Ga–Zn alloy showed a difference of ca. 0.9 V in U and Zr deposition potentials. Separation factor of zirconium and uranium in a "molten salt – liquid Ga-Zn alloy" system was determined. [ABSTRACT FROM AUTHOR]

This results of studying the process of concentration of high-level radioactive raffinates on falling film evaporator are presented. The work was carried out using simulate solutions on a large scale evaporator stand. [ABSTRACT FROM AUTHOR]

The current study aims to estimate the radiological hazard of the investigated granitic rocks by radioactive methods for the geo-chemical analyses, practically the activity levels and distribution of natural terrestrial radionuclides of 226Ra, 232Th and 40K were measured by ICP and XRF for samples of the investigated granitic rocks collected from Um Taghir area. The purpose of the study was to determine the radiological hazards of investigated granites to use in the field of construction and adornment or not and the extent of their impact on those who use them in their homes or for other purposes. We concluded that the average value of Raeq was found to be 88.78 Bq kg-1 as well as the estimated highest value of 141.38 Bq kg−1 of Raeq in the present work was lower than that of the recommended maximum value of 370 Bq kg−1. The range of measured activities differed widely as their presence in rocks samples depends on their physical, chemical and geo-chemical properties and the pertinent environment. [ABSTRACT FROM AUTHOR]

Thin Bi2Te3 films with a specially created thickness gradient were obtained by thermal deposition in vacuum. The methods of transmission electron microscopy in films revealed crystallographic orientations of the [100] and [2-21] tellurium phases. The method of bending contours in the films revealed a significant internal bending of the crystal lattice, reaching 150 deg / µm. [ABSTRACT FROM AUTHOR]

The article discusses the possibilities of innovative technology 3D modeling in LigroGame for the development of engineering thinking of preschool children in the framework of the additional program "Play and model in LigroGame", provides examples of creating children's projects on the model "invent-design-implement-manage" based on computer 3D modeling and additive technologies. [ABSTRACT FROM AUTHOR]

Emergence of bacterial infections in place of implant installation could provide some health and financial problems. One of the most promising method which could prevent disease is silver coatings applying on implants. Silver nanoparticles have a bacteriostatic and bactericidal effect however they are harmless for organism. In this work, we explored silver coatings with different thickness which were applying by pulsed ion-plasma method on the glass slide. The results are demonstrating non-linear dependence of antibacterial effect on the coat thickness. The most effective one is 750 nm thickness coat. [ABSTRACT FROM AUTHOR]

Identification and description of problems of augmented reality marker recognition technology. [ABSTRACT FROM AUTHOR]

The possibility of creating an anti-icing self-heating coating based on carbon nanotubes was explored. The influence of the quantity of coating layers on its conductive properties was studied. The possibility of modification of conductivity through annealing has been explored. Dependences of conductivity on the duration of the process of annealing are shown. An explanation to these dependences is given. A comparative analysis of the dependences for different types of CNTs has been conducted. [ABSTRACT FROM AUTHOR]

The determination of oxygen content in complex oxide by carrier gas hot extraction was applied. The causes of a random error were investigated. The main source was determined as the calibration procedure. [ABSTRACT FROM AUTHOR]

The results of testing method of synthesis of a high-entropy AlNbTiVZr alloy using metallothermic reduction of group IV and V metals from their oxides are presented. At the first stage, joint aluminothermic reduction of metals was performed in a resistance furnace. Then, to achieve uniformity and remove harmful impurities, the metal was remelted in a vacuum furnace with an inert atmosphere. The alloy obtained after the second remelting was subjected to chemical and x-ray phase analysis. The results of the analysis revealed the presence of a solid solution of Zr (Nb, V) with TiAl inclusions, confirming the prospect of using metallothermic synthesis to produce a high-entropy alloy with a single-phase structure. [ABSTRACT FROM AUTHOR]

Software has been created to provide data to mobile devices using wireless technologies. This application provides data exchange between data pickup device and mobile devices with possibility of processing received data. [ABSTRACT FROM AUTHOR]

This work is devoted to the tricky question of quantum observables calculation at low temperatures in framework of Heisenberg model. It was analytically showed that Hilbert space fragmentation can prevent the drastic growth of Gibbs exponent, which could occur if one successively considers the model from one fragment to another, without knowledge about ground state energy. In view of strong limitations of available computational resources this result favors researchers to study large scale models at low temperatures with stable observables accumulated from the fragments. [ABSTRACT FROM AUTHOR]

The evolution of photonic droplets in a medium of carbon nanotubes of the «zig-zag» type has been considered. It was shown that the propagation of photonic droplets is stable, the pulse energy remains localized in a limited spatial region. [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]

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]

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]

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]

A potentiometric method for determining the antioxidant capacity of objects containing compounds of different hydrophilicity using the K3[Fe(CN)6]/K4[Fe(CN)6] system as an oxidizing agent is proposed. The developed method determines antioxidant properties of vitamin preparations containing compounds of different hydrophilicity, namely the ascorbic acid and the α-tocopherol. A comparative analysis of the amount of active substance have been made according to the data declared by the manufacturer and determined experimentally. [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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]