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New NZP-type solid solutions, Na1+2xZr2–xNix(PO4)3 and Ca0.5+xZr2–xNix(PO4)3 with x = 0.10, 0.25, and 0.50, have been prepared by solid-state reactions. The synthesized samples have been characterized by X-ray diffraction and IR spectroscopy. Crystal structure of the compound CaZr1.5Ni0.5(PO4)3 has been refined by full-profile X-ray diffraction analysis method, reliability factors is Rp = 4.78% and Rwp = 6.45%, respectively. Thermal expansion of the phosphates has been studied by high-temperature X-ray diffraction in the temperature range 25–700°C. The synthesized compounds have been shown to be intermediate- and low-thermal-expansion materials. Using SPS method we have produced ceramic samples with a high relative density (ρrel > 97%), based on phosphate powders. Strength characteristics (microhardness and fracture toughness) of the ceramics have been determined.

Research subject. The gold-sulphide-quartz deposits of Central Chile are typical prospecting objects, having small ore intervals (from the first tens of centimetres to 1 m), intermittent and nested ore distribution and extremely uneven gold contents.Materials and methods. The patterns of ore mineralization distribution are considered against the background of the results of modern geophysical studies of the lithosphere: the Moho surface, density and thermal regime of the upper mantle. Detailed studies were conducted on the Yapin ore field.Results. It was shown that the faults controlling gold-sulphidequartz mineralization are derivatives of shear tectonics under the conditions of a transpression regime along the Chilean active margin. At an early stage, these faults developed in a right-shift environment, which was accompanied by the introduction of diabase dikes into the northeastern faults, and gold-sulfide-quartz mineralization superimposed on the dikes was deposited during the left-shift stage. The geological structure of the deposits in the ore field Yapin was characterized. It was shown that a diverse mineralization is developed in the ore field - copper-porphyry, IOCG-type and gold-sulphide-quartz. According to geochemical data, the latter is characterized by a clear enrichment of chalcophilic elements (Au, As, Ag, Cd, Cu, Bi, Pb, Zn, Te, Co). The marked enrichment of Bi, Te and Co ores indicates the participation of magmatic fluid in ore formation and the similarity of the mineralization of the Escondida deposit with the type of gold deposits associated with granitoid intrusions. According to geochemical features, gold-sulphide-quartz mineralization in the general zoning pattern occupies a boundary position between IOCG-type objects and copper-porphyry deposits.Conclusions. The conclusion is drawn about the independence of gold-sulphide-quartz mineralization and its difference from epithermal gold deposits. It is noted that, in the volcanic belts of the North-East of Russia, the prospects for discovering unconventional gold-sulphidequartz deposits similar to those of Central Chile are rather real.

One of the problems solved by analyzing the data of long-term Video EEG monitoring is the differentiation of epileptic and artifact events. For this, not only multichannel EEG signals are used, but also video data analysis, since traditional methods based on the analysis of EEG wavelet spectrograms cannot reliably distinguish an epileptic seizure from a chewing artifact. In this paper, we propose an algorithm for detecting artifact events based on a joint analysis of the level of the optical flow and the ridges of wavelet spectrograms. The preliminary results of the analysis of real clinical data are given. The results show the possibility in principle of reliable distinguishing non-epileptic events from epileptic seizures.

The SINP MSU is implementing a program to create compact detectors for studying the atmosphere and near-Earth space from small spacecrafts of the Cubesat type. Within the framework of this program, the AURA detector of ultraviolet radiation of the Earth’s atmosphere described in this article has been developed and tested. The device is a four-channel photometer based on silicon photomultiplier from the SensL Co. Its compactness, low supply voltage, and durability are the factors that determine the advantages for its use in nanosatellites.

Features of high-speed sintering of WC–Co nanopowders with various contents of excess carbon (colloidal graphite) were studied. Powders were obtained in a process that included plasma-chemical and low-temperature syntheses and a chemical-metallurgical method of applying ultrathin cobalt layers by precipitation from a solution of salts. Powder materials were consolidated by high-speed spark plasma sintering. It was found that an increase in the concentration of free carbon (colloidal graphite) has the greatest effect on the shrinkage and the sintering rate at the stage of intense shrinkage of WC–Co nanopowders. It was revealed that the process of nanopowder compaction at the intense shrinkage stage is determined by the intensity of the plastic flow and the intensity of diffusion along the boundaries of cobalt grains. It was shown that the mechanism of plastic deformation of the cobalt-based γ phase corresponds to the Coble diffusion creep. It was found that an increase in carbon content lowers the activation energy at the stage of intense shrinkage and does not significantly affect the activation energy at stage III of sintering, where the shrinkage intensity is observed to decrease. It was shown that a decrease in the sintering activation energy is due to a decrease in the tungsten concentration in the γ phase.

The Burgali deposit is located in the Paleozoic Kedon volcanic belt (KVB) within the Omolon cratonic terrane. The orebodies of the Burgali deposit are veined and stockwork-type. The studies of the wallrock metasomatites demonstrate that the erosional truncation of the deposit is close to minimal. The ores of the deposit are enriched in the chalcophile elements (Au, Ag, As, Sb, Te, W, Mo, and Bi) and poor in the rare earths. The rare-earth element (REE) spectra are dominated by light lanthanides. The ores are characterized as very low-sulfidation with finely disseminated mineralization, widespread occurrence of chalcedony, and widespread colloform-banded, often combined with brecciated, structures. The late quartz veins contain Lower Carboniferous coaly siltstone fragments, filled with petrified timber remains, which indicate the Carboniferous age of the ore mineralization. The ores contain widespread Au- and Te-bearing pearceite and rare minerals such as argyrodite and the selenous petrovskaite and uytenbogaardtite. The data obtained enable the Burgali deposit to be classified as low-sulfidation epithermal. The outlook for Ag and Au reserve additions is based on the further studies and exploration of the ore-bearing stockwork.

This article describes the development of a method for improving the security of fingerprint identification systems. It is based on the calculation of the polarimetric parameters of biological tissue using Mueller matrices. This method was tested on samples made from gelatin, which have a copy of the papillary pattern and mimic real tissue. It is shown that the proposed method is promising for solving the problem of increasing the security of fingerprint sensors from breaking using finger models. In conclusion, recommendations are given for improving the polarimetric method.

The article is devoted to the results of mineralogical and geochemical studies of argillizites at Compleksnoe Au–Ag ore occurrence, localized on the southern flank of the Kajenmyvaam volcanic uplift in the inner zone of the Late Cretaceous marginal–continental Okhotsk-Chukchi volcanic belt (OChVB). At the ore occurrence, a series of isometric (oval) in plan view argillizite “hats” with diameters of 200 to 900 m are described. They are composed of red and light gray clay formations and accompanied by complex (Au–Ag–Mo–Cu–Pb–Zn–Bi–Sn) anomalies. In the recent relief, argillizite “hats” are characterized by gently sloping domes and crown subvolcanic bodies of granitoids and explosive breccias. A series of argillizite “hats” is surrounded by elongated lenticular bodies of secondary quartzites, which form the outer boundary of a large annular volcanostructure. The argillizites are composed of the following minerals: illite-smectite (mixed-layered formation), kaolinite, muscovite, jarosite, quartz, and rutile. The average content of Au and Ag in bulk samples are 0.06 and 0.075 g/t, respectively. Au is found in invisible form. According to the geological and geochemical data, argillizite “hats” record a near-surface (up to 300 m), slightly eroded, level of a large porphyry-epithermal mineral-forming system.

A glycine–nitrate self-propagating high temperature synthesis (SHS) was developed to produce composite Y2O3–MgO nanopowders. Based on the thermodynamic calculations a 0.25YMg2(NO3)7-0.75NH2CH2COOH precursor composition was selected to prepare low agglomerated uniform composite yttria-magnesia powder. Near full dense composite ceramics were fabricated based on the prepared powders by the spark plasma sintering method. IR-transmittance and hardness of the Y2O3–MgO ceramics were studied in correlation with sintering conditions. The best transmittance of 80.9%@5 μm and Hv = 10.2 GPa were measured for the sample obtained at 1150 °C.

Physical the bases of acoustic-topographic method of defektoskopiya of multilayer structures are briefly covered. Installation for implementation of acoustic-topographic method in two options is developed and mounted: with the magnetostrictive activator and with the electromagnetic (shock) activator. By pilot studies it is established that at control by acoustic-topographic method of brazed and welded structures sensitivity of control significantly (in 2–3 times) is higher, than at control by other methods of defektoskopiya. It is established also that the zone of control of multilayer glued structures is much less, than at control of brazed and welded structures. It is shown that the greatest thickness of the upper leaf of structure at which control by acoustic-topographic method with sufficient sensitivity is still possible, is equal to about 1 mm, at control of structures with thickness of the upper leaf initiation of elastic oscillations it is reasonable to carry out over 1 mm in the shock way. Repeated control with change of point of input of ultrasonic oscillations is in certain cases necessary for specification of picture of distribution of powder near initial point of input of oscillations.

Research subject. The Mississippi Valley type deposits make up about a third of the global balance of lead and zinc reserves, resources and production. Additionally, silver, antimony, arsenic, barium, bismuth, cadmium, cobalt, gallium, indium, mercury, molybdenum, nickel and thallium can be present in the ores of these deposits. In the North-East of Russia, the Mississippi Valley type of deposits is poorly represented. In this work, we investigate the deposits of the Sardana ore cluster of the Republic of Sakha (Yakutia) and individual deposits of the Magadan region. Materials and methods. The article discusses the results of previous scientific research and new data on the geochemical features, isotopic composition of ores and geological and structural conditions for the formation of the Sardana cluster deposit. In addition, the potential for identifying stratiform lead-zinc deposits is associated with favourable geodynamic conditions in the region, as well as with the refinement and adaptation of the forecast-search model of MVT deposits for the North-East of Russia. Results. The mineralogical and geochemical features of the rocks and ores of the Sardana cluster deposits, the morphology of ore bodies, their zoning elements, as well as isotopic ratios indicate that the ores are likely to be of the Mississippi Valley type with the onset of ore deposition at early diagenetic and catagenetic stages. The distribution of rare elements indicates a significant role of superimposed metamorphism of the host carbonate-terrigenous strata in the deposition of the ores of producing stages. Conclusion. The potential possibility of increasing the mineral and raw material base of lead and zinc is associated with the identification of sedimentary basins with a stagnant anoxic regime of carbonate accumulation in the immediate vicinity of the development areas of rift complexes, as well as with the presence of other critically important forecast-search signs. In addition to the well-known Killakh metallogenic zone, Tuora-Sis and Orulgan metallogenic taxa located in the north of the Republic of Sakha (Yakutia) with known stratiform manifestations of lead and zinc belong to such areas.

The Valunistoe Au–Ag deposit is the third largest among epithermal deposits in Chukotka after the Kupol and Dvoinoe. It is located at the western closing of the East Chukotka flank zone of the Okhotsk-Chukotka volcanic belt. Volcanic domes (Pravogornenskaya, Zhil’ninskaya, Shakhskaya, Valunistaya, Shalaya, and Oranzhevaya, each is 3–6 km in diameter) have the main ore-controlling significance in the area; they form a chain elongated to the northeast, along the Kanchalan fault zone. Near the deposit, Upper Cretaceous volcanics are widespread: ignimbrites, lavas and tuffs ranging from rhyolite to basaltic composition, and lenses and interbeds of sedimentary rocks, subvolcanic bodies and dikes of andesites, basalts, and dacites. The structure of the deposit is caused by its localization within the limits of the eponymous (Valunistaya) volcanic dome. Twelve ore-bearing vein zones with thicknesses ranging from several to several tens of meters have been revealed at the deposit. The Glavnaya (Main) and Novaya (New) vein zones have been studied in detail; they are traced along their strikes to a distance of more than 1500 m and consist of en echelon veins 1.0 m thick on average, with lengths varying from 100 to 400 m. Based on the sampling data, Au and Ag contents in ores are 0–474.3 and 0–3794.23 g/t, respectively. Colloform-banded structures are frequently encountered, often combined with breccia structures. The main vein minerals are quartz and adularia; calcite, chlorite, fluorite, sericite, pyrophyllite, kaolinite, montmorillonite, gypsum, and epidote are less frequent. The main ore minerals are pyrite, acanthite, chalcopyrite, galena, sphalerite; secondary ore minerals are native Au and Ag and polybasite; rare ore minerals are pearceite, magnetite, hematite, marcasite, freibergite, tetrahedrite, bournonite, hessite, matildite, and others. Ores are characterized by an Au/Ag ratio from 1 : 5 to 1 : 10 and sulfidity (0.5–5%). Ores are enriched in many elements (Au, Ag, Sb, Cd, Pb, Cu, Zn, As, Se, Mo, Te, and Cr), with enrichment factors ranging from several times (Se, Mo, Te, and Cr), to tenfold (Cd, Pb, Cu, and Zn) and hundredfold (Sb) levels, reaching an excess of tens and hundreds thousand times for Au and Ag (Fig. 7). Ores are characterized by a low total REE and demonstrate positive Eu anomalies. Geochemical features are consistent with the mineral composition of ores. Full homogenization of fluid inclusions in quartz occurs at temperatures of 203–284°C and 174–237°C in calcite, while the salt concentration in both cases is from 0.2 to 0.7 wt % NaCl equiv. Fluid density changes from 0.87 to 0.56 g/cm3. The results give grounds to attribute the Valunistoe deposit to the low-sulfidized epithermal class. The data provided in the article are of practical value for regional forecast–metallogenic maps and can be used in searching for and appraising epithermal Au–Ag deposits.

This paper describes an experimental study pertaining to laser ignition of igniters of liquid rocket engines operating on such propellants as O $$_{2g}$$ + kerosene, O $$_{2g}$$ + ethanol, and O $$_{2g}$$ + H $$_{2g}$$ , and to how they ignite the propellant of a model combustion chamber. A quartz fiber based optical device is described, which allows for multiple ignition of the igniter and the combustion chamber without replacing the device. This study also touches upon possible types of pulsed lasers used in the laser ignition system, a fiber-optic laser igniter that remain hermetic and operable at a combustion chamber pressure of up to 10 MPa and more than 100 ignition cycles.

The thermodynamic characteristics of adsorption (TCA) of thiophene and its derivatives are determined under the conditions of equilibrium gas adsorption chromatography (GAC) on columns with graphitized thermal carbon black (GTCB) of Carbopack C HT grade. It is shown that the TCA values ​​ depend largely on the number and nature of the substituents in the main structural fragment. It is found that the surface of the GTCB is characterized by low structural selectivity for positional isomers in the series of thiophene derivatives. The effect of polar retention of an adsorbate on graphite from the gas phase due to additional intermolecular specific interactions of polar groups of the adsorbate with an easily polarizable surface of the base face of graphite is established and studied. Conclusions are reached on the applicability of the two-dimensional ideal gas model for describing the mobility of strongly polar molecules of thiophene derivatives on surfaces of graphite, and on the considerable limitations of this model when applied to the adsorption of thiophene molecules, along with its methyl and halogen derivatives.

Operation capabilities of ultrasonic through transmission method of non-destructive testing of products from polymeric composite materials and multilayer glued structures are considered. It is shown that for detection of defects in products from easily damaged materials, from the hydroscopic materials which are not allowing wetting by liquids, in designs with rough surface, and also for detection of the under surface defects which are not revealed by contact methods, effective use of ultrasonic through transmission noncontacting method. The calculation procedure and designing of ultrasonic through transmission noncontacting probes on the frequency of 200 kHz, allowing to reveal defects in products from polymeric composite materials and in multilayer glued structures with higher sensitivity, than noncontact ultrasonic probes applied now on frequencies 20, 40 and 80 kHz is offered. The constructive scheme of the vibrator with two piezoelectric plates from ceramics TsTS-19, included inphase, with the metal lap playing role of wave guide, and matching layer from foam plastic is provided. It is specified that two piezoelectric plates works in “short circuit” mode therefore sound pressure piezoelectric plates increases by acoustic line twice, and oscillation strength four times.

The research results of the microstructure and corrosion resistance of Ti and Ti-Al-V Russian industrial titanium alloys obtained by spark plasma sintering (SPS) are described. Investigations of the microstructure, phase composition, hardness, tensile strength, electrochemical corrosion resistance and hot salt corrosion of Ti-Al-V titanium alloy specimens were carried out. It was shown that the alloy specimens have a uniform highly dense microstructure and high hardness values. The studied alloys also have high resistance to electrochemical corrosion during tests in acidic aqueous solution causing the intergranular corrosion as well as high resistance to the hot salt corrosion. The assumption that the high hardness of the alloys as well as the differences in the corrosion resistance of the central and lateral parts of the specimens are due to the diffusion of carbon from the graphite mold into the specimen surface was suggested.

Mainstreaming of the issue of resources in the implementation of enterprise development strategies makes it necessary to determine the extent of its impact on the efficiency and quality of labor, with a focus on the formation and use of a whole range of social resources. The presented study is based on a decade of comparative research that covers 19 industrial enterprises across Saint Petersburg to examine the effects of resources on the efficiency of an enterprise in pursuaing its strategic objectives.Aim. The study aims to substantiate the way resources increase performance and improve the efficiency of development strategy implementation in indusitral enterprises.Tasks. The authors perform a theoretical and empirical analysis of the problem of using the social resources of industrial enterprises, analyze risks of insufficient management support in a market economy, and develop a set of measures aimed at optimizing the use of internal resources to increase the performance of industrial enterprises.Methods. The theoretical and methodological basis of the study includes the interview method, expert assessment, content analysis, and findings of foreign and Russian scientists in the field of social and labor relations, development of labor potential, improvement of the enterprise management system, formation of behavioral practices among employees to improve labor efficiency.Results. This study provides a practical assessment of social resources at industrial enterprises in terms of the social expectations of employees, the level of trust between individuals and groups, commitment to the goals and values of the enterprise, opportunities for creative and professional fulfilment, perception of the fairness of compensation, social and psychological climate, etc. It is established that disregard for the resource component leads to social and psychological division, divergence of values, spiritual and moral positions, employee performance benchmarks, and impaired productivity in general. The study substantiates the importance of coordinated goals for each functional unit; procedures for continuous collection and analysis of enterprise performance data; development ofprofessional knowledge, skills, abilities, and experience; the need to identify, assess, and provide managerial support for the socially important qualities of employees.Conclusions. The obtained empirical data make it possible to develop a set of measures for industrial enterprises to identify, assess, and provide managerial support for the socially important qualities of employees, and to optimize the use of internal reserves that are the most significant resource for the enterprise development strategy.

The study focuses on corrosion fatigue processes taking place in an ultrafine-grained (UFG) near-α-titanium alloy Ti-2.5Al-2.6Zr (Russian industrial name PT7M) used in nuclear engineering. UFG structure formed with Rotary Swaging is found to increase resistance to corrosion fatigue. Parameters of the Basquin's equation are defined and the slope of the fatigue curve σa-lg(N) is shown to depend (nonmonotonic dependence) on the UFG alloy annealing temperature. This effect can be explained with the patterns of microstructural evolution in a UFG alloy PT7M during annealing: (1) reduced density of lattice dislocations, (2) precipitation and dissolution of zirconium nanoparticles, (3) release of α′′-phase particles causing internal stress fields along interphase (α-α′′)-boundaries, and (4) intensive grain growth at elevated annealing temperatures. It is shown that the fatigue crack closure effect manifested as changing internal stress fields determined using XRD method may be observed in UFG titanium alloys.

The results of studying the efficiency of the laser-acoustic method of ultrasonic testing in determination of the degree of polymerization of the matrix of polymer composite material (PCM) are presented. We have studied the PCM samples used for manufacturing integrated structures. It is shown that excessive degree of polymerization of the preformed blanks leads to a decrease in the strength of connection of the structural elements and precludes obtaining the desired shape and geometric dimensions of the product. We developed fundamentally new diagnostic parameters, which are characterized by high reliability and accuracy of determination. To forecast sample curing regimes with given values of the degree of transformation, the reaction kinetics was analyzed using differential scanning calorimetry Experimental results used for calculation of the kinetic parameters were obtained on a thermoanalytical complex DSC 1 (Switzerland). The kinetic parameters of polymerization and degree of binder curing in plastics were determined by the thermal effect of the reaction. It is shown that when determining the degree of polymerization of a PCM matrix by an ultrasonic method (laser-acoustic method of exciting ultrasonic vibrations), the product of attenuation of the bottom signal of longitudinal ultrasonic vibrations by the signal round-trip time and energy of the structural noise (thus taking into account the porosity of the material), can be used as reliable parameters of diagnostics. The proposed method provides higher accuracy compared to other methods used for control of the degree of polymerization.

In this paper, an algorithm for automated detecting diagnostic events in video channel of video and electroencephalographic (EEG) monitoring data is presented. The analysis of video sequences is focused on identifying a group of frames with high or very low (depending on the type of seizure) dynamics of informative areas according to a criterion calculated during processing of the optical flow. The preliminary results of the analysis of real clinical data are given and compared with data obtained from the synchronous EEG. The results showed the possibility in principle of reliable diagnosing epileptic seizures and distinguishing them from non-epileptic events.

The sol-gel synthesis of ZnAl2O4 ceramic powders from alkoxide and acetate sources of metals, as well as the microstucture and the hardness of the hot-pressed ZnAl2O4 specimens were considered. ZnAl2O4 powders were prepared by the hydrolysis of an alcohol solution of aluminium isopropoxide using an aqueous solution of zinc acetate followed by heat treatment. The thermal evolution of the ZnAl2O4 precursor was investigated. The effect of calcination temperature on the morphology and the specific surface area of ZnAl2O4 powders were also studied. The sintering of the resultant powders to the high transparent ceramic using a hot pressing with 1 wt% ZnF2, as a sintering additive was successfully demonstrated. The in-line transmittance of ZnAl2O4 ceramics (1 mm thickness) achieved 80% in the visible region and 85% at 5 µm; Vickers hardness was 11.6 GPa.

Applicability of Spark Plasma Sintering has been studied for production of high-density (98.6–99.5%) composite ceramics Y2.5Nd0.5Al5O12 (YAG:Nd) – x MgO (x = 5, 10, 20 vol %). Powder YAG:Nd-MgO compositions have been obtained by precipitation of the MgO phase from Mg(NO3)2 water solution of magnesium nitrate onto the surface of garnet nanoparticles YAG:Nd. It has been demonstrated that the intensity of sintering fine-grained YAG:Nd-MgO composites is governed by volume diffusion at low temperatures and by grain boundary diffusion at high temperatures. Faster sintering at low temperatures is caused by formation of MgAl2O4 spinel particles and internal stress fields that are manifested as broadening and shifting of garnet peaks in the sintered composites.

Spark Plasma Sintering has been used to obtain first ever fine-grained SrWO4 and NaNd(WO4)2 ceramics with the scheelite structure and high density (95.8–99%) that are promising as materials for nuclear waste immobilization. It has been demonstrated that the densification intensity in tungstates at the initial sintering stage is determined by the agglomeration degree of input powders. The activation energy of fine-grained ceramics with the scheelite structure has been established to correlate at high temperatures with the activation energy of grain-boundary diffusion. Rapid sintering of fine-grained NaNd(WO4)2 ceramic results in internal tensile stress fields that lead to lowered hardness and fracture toughness of the ceramic.

This paper reports on new data on δ34S and δ18O isotopy for trace and rare-earth elements of the Au deposits of the Glukharinskii ore cluster. The geochemical features indicate the reducing conditions of the ore deposition and the involvement of a magmatogenic fluid in ore-forming and point to the host rocks as possible sources of ore matter. On the basis of the isotopic data, it was determined that the ore-forming fluid has a mixed metamorphogenic–magmatogenic composition. The results suggest that the studied objects can be confidently considered as Au deposits related to granitoid intrusions.

The mechanisms of paleodeformations during the time of fluid inflow into the accumulation area of gold ore concentrations were studied for two deposits. It was found that the mechanisms corresponded to seismic mechanisms of the DC- and NDC-types. The key effect of the deformation mechanisms as such on the migration of fluids consists in the formation of different structural and hydrodynamic organization of the ore-forming system depending on the parameters of fluid conditions, as well as in controlling the fluid flow within the accumulation area of ore concentrations.

The potentially large Primorskoe epithermal Au-Ag deposit is represented by three areas: the Kholodnyi, Spiridonych, and Teplyi. It is located in the Omsukchan district of Magadan oblast, where mining is carried out at the largely similar Dukat, Lunnoe, Gol’tsovoe, Arylakh, Tidit, Pereval’noe, and other deposits. The deposit under review is located in the Kalalaga volcano-tectonic depression, where ore has been emplaced in a gently dipping sequence of Late Cretaceous ignimbrites and rhyolites more than 700 m in thickness crosscut by numerous intermediate and mafic dykes. According to drilling data, there is a leucocratic granite massif 400–500 m beneath the deposit, which is exposed on the surface in the northeastern part of the ore field. The presence of Bi-bearing galena and matildite, as well as medium- to high-temperature metasomatic facies (epidote and actinolite) and the specific physicochemical conditions of epithermal Ag-Au ore emplacement, attests to the above-intrusion position and the role of granitoids as high-temperature magmatic fluid generators responsible for supplying Bi and heating the host rock. The ore chemistry is quite consistent with its mineral composition. High Mn and Ag; elevated Au; low Cu, Pb, Zn, Sb, As, Bi, and Te; and low total REE concentrations were established, along with negative Eu and positive Ce anomalies. The high Te/Se, Sr/Ba, Y/Ho, and U/Th ratios in the ores are due to their location in the area influenced by the granitoid pluton. The physicochemical parameters of ore emplacement in the Teplyi area are unusual: high temperatures, low salt concentrations, and fluid densities typical of a “dry vapor” environment. The obtained data allow the Primorskoe to be classified as an intermediate sulfidation epithermal deposit. The data discussed below are of practical use for regional metallogenic forecasting, exploration, and economic assessment of epithermal Ag-Au deposits.

Density functional theory (DFT) calculations have been used to study the band structure and density of states of a Ga1 – xMnxAs diluted magnetic semiconductor. It has been shown that some of the Mn 3d states are hybridized with the valence band at the Fermi level. Magnetic properties have been calculated by a multiscale method using DFT densities of states and exchange integrals calculated for a Mn atom by the Hartree–Fock method. The theoretical ferromagnetic transition temperature TC of Ga0.9375Mn0.0625As agrees with experimental data. spintronic materials, diluted magnetic semiconductor, GaAs, Mn, density functional method, density of states, band structure

We have studied the feasibility of preparing high-density (98.6–99.5%) Y2.5Nd0.5Al5O12 (YAG)–xMgO (x = 5, 10, 20 vol %) composite ceramics by spark plasma sintering. YAG–MgO powder materials have been prepared via MgO precipitation from an aqueous solution of magnesium nitrate, Mg(NO3)2, on the surface of garnet particles. The sintering rate of the YAG–MgO composites has been shown to be controlled by volume diffusion at low temperatures and by grain-boundary diffusion at elevated temperatures.

This paper describes the protocol for generating a master key for a system for exchanging fiscal features, generating a fiscal feature key with authentication of the means for generating and verifying fiscal features that are installed on the fiscal drive and in the equipment of fiscal data operators and the authorized body. This protocol is based on the use of known domestic cryptographic transformations and is aimed at ensuring the integrity and authenticity of data transmitted through the communication channel between the means of formation and means of verification of fiscal features. The protocol was developed in accordance with the recommendations of Rosstandart regarding the principles of the development and modernization of encryption (cryptographic) means of information protection and was issued in the form of a draft national standard proposed for public discussion and approval in accordance with the established procedure. The main result of this study is the formulation of certain security properties that are identical to those objectives that the intruder sets for the purpose of compromise. Already at the stage of creating a protocol, taking into account methods of compromise makes it possible to establish such structural features in this protocol that would ensure the fulfillment of specified security properties and the subsequent justification of their sufficiency.

This paper considers the geochemistry and conditions of generation for the Mesozoic Au–Ag epithermal deposits in the Okhotsk–Chukchi volcanic–plutonic belt (OChVB) in Northeast Russia. We provide new data on the composition and concentrations of trace elements, including REEs, in the ores of epithermal Au–Ag deposits. The ores were found to be enriched in a wide range of trace elements. The REE distributions of these ores are dominated by light “hydrophile” lanthanoids of the “cerium” group. The Eu anomalies were found to vary between high negative to low and high positive levels. Comparative analysis over the classes of gold concentration showed a synchronous enrichment of the ores in similar sets of trace elements. A study of fluid inclusions revealed that the ore-forming solutions had hydrocarbonate potassium or hydrocarbonate sodium compositions. The fluids had high concentrations of sulfate ions for most deposits. The salinity of the fluids was frequently found to increase toward later low-temperature mineralization phases. We identified the tendency of increasing K+ percentage in the fluid from the earlier oreless quartz to productive quartz with increasing depth, as well as some decrease in the percentages of Na+, Ca++, and Cl–. The results indicate magma chambers of andesite magmas and meteoric waters as the most likely sources of the fluids that generated the epithermal Au–Ag ores in the OChVB deposits.

The Dvoinoe Au-Ag low-sulfide epithermal deposit is located in the Ilirnei ore district (western Chukotka) within the outer zone of the Okhotsk–Chukotka volcanic belt (OChVB). The paper considers the results of geological–structural, mineralogical–geochemical, and thermobarogeochemical studies of the deposit. The ores of the deposit are characterized by dominant colloform-banded (often combined with brecciated) structures; a high Au/Ag ratio (1: 1 to 1: 2); low sulfidity (

This work deals with the problem of canvas threads counting in images of paintings. Counting of threads is necessary for measuring canvas density and a number of other parameters used by art historians for dating the artworks. We propose to use raking light in the image acquisition process in order to emphasize canvas texture. We improve known techniques developed for inspecting fabrics in the textile industry. Two new threads counting algorithms based on filtering in the Fourier domain and mutual information maximization thresholding techniques are proposed and tested. These algorithms for measuring the canvas density from images taken in raking light are efficient in cases when the analysis of canvas images acquired in X-rays and transmitted light is ineffective. The results of the experiment show that the accuracy of the proposed threads counting algorithms is comparable to the accuracy of known techniques. The analysis of the characteristics of canvases of paintings by F.S. Rokotov allowed obtaining an informative feature that can be used by art historians and experts for dating the artworks.

Admittance spectroscopy is used to study hole states in Si0.7–yGe0.3Sny/Si quantum wells in the tin content range y = 0.04–0.1. It is found that the hole binding energy increases with tin content. The hole size-quantization energies in structures containing a pseudomorphic Si0.7–yGe0.3Sny layer in the Si matrix are determined using the 6-band kp method. The valence-band offset at the Si0.7–yGe0.3Sny heterointerface is determined by combining the numerical calculation results and experimental data. It is found that the dependence of the experimental values of the valence-band offsets between pseudomorphic Si0.7–yGe0.3Sny layers and Si on the tin content is described by the expression ΔEV exp = (0.21 ± 0.01) + (3.35 ± 7.8 × 10–4)y eV.

Mini-EUSO is a telescope observing the Earth in the ultraviolet band from the International Space Station. It is a part of the JEM-EUSO program, paving the way to future larger missions, such as KEUSO and POEMMA, devoted primarily to the observation of Ultra High Energy Cosmic Rays from space. Mini-EUSO is capable of observing Extensive Air Showers generated by Ultra-High Energy Cosmic Rays with an energy above 10^21 eV and detect artificial showers generated with lasers from the ground. Other main scientific objectives of the mission are the search for nuclearites and Strange Quark Matter, the study of atmospheric phenomena such as Transient Luminous Events, meteors and meteoroids, the observation of sea bioluminescence and of artificial satellites and man-made space debris. Mini-EUSO will map the night-time Earth in the UV range (290 - 430 nm), with a spatial resolution of about 6.3 km and a temporal resolution of 2.5 microseconds, through a nadir-facing UV-transparent window in the Russian Zvezda module. The instrument, launched on August 22, 2019 from the Baikonur cosmodrome, is based on an optical system employing two Fresnel lenses and a focal surface composed of 36 Multi-Anode Photomultiplier tubes, 64 channels each, for a total of 2304 channels with single photon counting sensitivity and an overall field of view of 44 degrees. Mini-EUSO also contains two ancillary cameras to complement measurements in the near infrared and visible ranges. In this paper we describe the detector and present the various phenomena observed in the first months of operations., 23 pages, 20 figures

New data obtained using a modern analytical technique on the geochemistry and conditions of the formation of Mississippi-type ores at the Sardana deposit are presented. Comparative analysis related to other deposits of the same type was carried out. The geochemical data point to a considerable role of metamorphism of the enclosing carbonate–terrigenous masses in ore formation at the deposit.

The new geochemical data obtained of cupriferous sandstones of the Orenburg area of the Ural region show that the Permian host stratum could have served as the source of rare-earth elements and other microelements for the ore-forming fluids. They confirm the possibility of using a convection model to explain the genesis of the copper ores studied. This model indicates the likely multistage development of mineralization to significant depths, like in the Manto deposits in Chili. Consequently, the Permian cupriferous sandstones of the southwestern area of the Ural region can be considered a very promising source of raw material for the development of copper industry in the area.

The Kuroko-Type ores of Hotaidokh deposit are enriched in a wide range of elements, compared to the average contents of elements in the upper crust. The REE spectrum of ores is dominated by light “hydrophilic” lanthanides of the “yttrium” group. The ores are characterized by low REE total contents, sharp positive Eu anomalies, as well as δEu ≫ 1, δCe < 1, and the average ratio Y/Ho ~ 48.13. Such index values indicate the deposition of ore minerals from high-temperature hydrothermal fluids becoming cold in an oxygen-bearing depth of a seawater body when the redox conditions change. Consequently, the pyritepolymetallic ores of the Hotaidokh deposit were formed from ore-forming fluids of an exhalation-hydrothermal origin. It should be noted that the data presented in this work on the composition and distribution of a number of trace elements and REEs in Kuroko-type ores of this deposit were obtained for the first time.

It is shown experimentally that in silver- and copper-containing barium-phosphate glasses metal subnanosized luminescent molecular clusters are formed during the glass synthesis. X-ray irradiation and the subsequent thermal treatment of these glasses result in the considerable change of their luminescence spectra in visible spectral region. This effect is caused by the transformation of the charge state of molecular clusters. In the luminescence spectra of the glass doped with silver and copper simultaneously new luminescence bands appear in comparison with the spectra of glasses doped only with one metal. The reason of this can be the formation of hybrid Ag n Cu m molecular clusters. The computer simulation of the structure and optical properties of such stable clusters by TDDFT method is presented.

This paper considers the geochemistry of volcanogenic mineralization in the northeastern segment of the Pacific Ore Belt (Northeast Russia). We give new evidence for the compositions and concentrations of trace and rare-earth elements (REE) in the ores of volcanogenic fields: Au-Ag epithermal (of various types and ages), Cu-Mo-Au porphyritic, Au-Bi related to granitoidal intrusions, Sn-Ag subvolcanic and kies polymetallic enriched in Au and Ag, as well as REEs in alkaline volcanic rocks. Geochemical signatures have been compiled for 17 formation types of volcanogenic fields. It was found that the ore-forming fluids in most fields belonged to an NaCl-H2O hydrothermal system that was enriched in Cl relative to F; the values of Y/Ho in the ores of nearly all types correspond with the interval of ratios characteristic for present-day hydrothermal fluids in backarc basins; most of the ores that we studied had near-chondrite spectra with configurations similar to those of the REE spectra in volcanic rock sequences of the andesite-diorite series. Comparative analysis of REE spectra in the distribution of trace elements over classes of gold concentration shows synchronous enrichment of ores in similar sets of trace elements. The high Co/Ni ratio in volcanogenic ores probably reflects the superposition of a later magmatic fluid upon an earlier mineralization. Samples from ores of volcanogenic fields, except for Kuroko, show δCe and δEu varying from negative to mildly positive values, thus indicating low-oxidizing conditions during deposition. It was found for Au-Ag epithermal ores that they are enriched in a wide range of trace elements; they have low concentrations of REEs, the light REEs are more abundant than the heavy ones, and the Eu anomalies vary considerably from small negative to low and high positive values. The results provide evidence of an exhalation hydrothermal origin of the Khotoidokh field. It has been shown that the REEs in the ores of the Bol’shoe field are of the type that is most valuable to industry. The results can be used to deal with practical problems: determining the formation type and evaluating the industrial value of a field; detecting accessory components in ores; and discriminating between the types of geochemical anomalies (in rocks or in soil) and stray fluxes as to the potential of a field.

The effect of Sc on plasticity at elevated temperatures(from 300 to 500 °C) and strain rates(from 10−3 to 10−1 s−1)of ultrafine-grained (UFG) Al–0.5%Mg–Sc alloyswas investigated. In the UFG alloys with 0.4% and 0.5%Sc at 500 °C and strain rate 1·10−1 s−1, high elongation to failure (~1060%) was achieved. The fractographic analysis of the fracturesin the Al–0.5%Mg alloy demonstrated the crack growth zone to occupy almost whole fracture area.The self-destruction in the crack growth zone has a viscous character.In the UFG alloys with Sc, numerous pits formed as a result of micropore junction were observed. Dependencies of dynamic grain growth (DGG) rate on the temperature and strain rate were determined. The DGG in the Al–0.5%Mg–Sc alloys was found. The kinetics of the DGG in the Al–0.5%Mg–0.2%Sc alloy was shown to be limited by mobility of junction disclinations. In the Al–0.5%Mg–0.5%Sc alloy, it is limited by mobility of oriented misfit dislocations. Al3Sc particles were shown to be possible origin of the micropore formation and of accelerated destruction of the Al–0.5%Mg–Sc alloys at high temperature deformation.

Density functional theory calculations have been used to study the electronic structure of Mn-doped, Ni-doped, and Mn/Ni-codoped InSb and GaAs semiconductors. The ferromagnetic transition energy has been calculated using a multiscale method in which exchange interaction is calculated by the Hartree–Fock exact atomic method and is then included as a Hubbard parameter in calculation of the electronic structure of the material. The present calculation results demonstrate that, in all cases, there is hybridization of the impurity d states with the valence band of the host semiconductor. The contributions of the Ni and Mn dopants are approximately additive.

The Plavica Au–Ag–Cu deposit is related to the large Neogene volcanic center, which complicates the paleocaldera in the central Kratovo–Zletovo ore district of eastern Macedonia. Based on the geology, ore mineralogy, wall-rock alteration, and fluid inclusions, the Plavica deposit has been referred to the epithermal high-sulfidation type. The general 3D model of orebody at this deposit is based on its general geological structure and complex distribution of metal contents. The framework of the 3D model, which has been constructed in the ArcGIS System, comprises 195 exploration boreholes 47295.8 m in total length. The 3D model allows to a better understanding of distribution of mineralization and supplements the geological data on the deposit.

Ores of epithermal Au–Ag deposits of the Okhotsk–Chukotka volcanoplutonic belt are characterized by enrichment in a wide spectrum of elements in relation to the average upper crustal values. The data obtained show that the host volcanic rocks are the most likely sources of minor elements and REEs for the fluids that formed epithermal Au–Ag deposits of the Okhotsk–Chukotka volcanoplutonic belt.

This paper is focused on the new data for geology, mineralogy, and geochemistry of stockworks consisting of steep and gentle quartz veins and veinlets forming a complex multilevel structure at the Rodion deposit. These stockworks range from 25 to 150 m in thickness. Average gold grade is 1.8 g/t. Ore minerals pyrite, arsenopyrite, chalcopyrite, sphalerite, galena, and native gold are predominantly concentrated on the vein and veinlet walls. Thermal metamorphism caused by the intrusion of the Ulakhan granodiorite pluton is the important singularity of the deposit. The deposit ore is enriched in chalcophile microelements Au, Ag, As, Sb, Cu, Pb, Zn, and Bi as compared to the average composition of the upper crust and hosting Permian sequences. The enrichment factors range from a few to hundreds of times. Bi, W, Pb, Ag, and Na2O are positively correlated between each other and with Au. The highest correlation coefficient 0.59 is between Au and Bi. Au is negatively correlated with Ba, Li, Co, Ni, Mn, Ti, and Be. The stockwork ores were formed involving homogeneous low-saline (9.4–4.3 wt % NaCl equiv) substantially aqueous bicarbonate-chloride fluid at 275–330°C and 300–1840 bar fluid pressure. Fluid has a high concentration of CO2 (up to 349 g/kg of water) and is reductive (СО2/СН4 = 17–37.3). Na and Ca are the major cations in the fluid, whereas K and Mg are minor. In addition, many microelements were detected in the fluid: As, Li, Rb, Cs, Mo, Ag, Sb, Cu, Zn, Cd, Pb, U, Ga, Ge, Ti, Mn, Fe, Co, Ni, V, Cr, Y, Zr, Sn, Ba, W, Au, Hg, and REE. The results obtained are consistent with the metamorphic–magmatic formation model of orogenic gold–quartz deposits within the Yana–Kolyma belt.

The geochemical features and conditions of formation of the Paleozoic epithermal Au–Ag mineralization in the pre-accretion Kedon (D2–3) volcanoplutonic belt located within the Omolon craton terrain are described. The new data on the composition and contents of trace and rare-earth elements (REEs) in igneous ores of epithermal deposits is provided. The elevated grades of a wide range of trace elements as compared to the average values of the upper crust have been identified.

A problem of image segmentation quality is considered. The problem is viewed as selecting the best segmentation from a set of images generated by segmentation algorithm at different parameter values. A segmentation quality model for selecting the best segmentation based on information redundancy measure is proposed. The developed technique was applied to SLIC and graph-cut segmentation algorithms. Computing experiment confirmed that the segmented image corresponding to minimum redundancy measure demonstrates suitable dissimilarity when compared with the original image. The segmented image which was selected using the proposed criterion, gives the highest similarity with the ground-truth segmentations.

This paper is concerned with the geochemical features and conditions of generation for Paleozoic Au–Ag mineralization in the pre-accretionary Kedon (D2-3) volcano-plutonic belt (KVB), which is situated within the Omolon cratonic terrane (Northeast Russia). We present new data on the compositions and concentrations of trace elements and rare-earth elements (REEs) in the host rocks and volcanogenic ores of epithermal Au–Ag fields. The ores are found to be enriched in a wide range of trace elements. The general features of the ores under study include a low level of REE concentrations, an obvious enrichment in light REEs, and considerable variations in europium anomalies, ranging from low negative to low- and strongly positive. Fluid inclusions were studied to show that the ore-forming solutions were hydrocarbonate potassium in composition. The mineral content of the fluid increases toward later, low-temperature phases of the mineralization. We found a tendency of potassium increasing from the earlier oreless quartz to productive quartz going to great depth, as well as a slow decrease in the concentrations of Na+, Ca++, and Cl–. The productive quartz shows direct correlation in Ag–K and a reverse correlation in Ag–Na. The results indicate andesite magmas and meteoric water as the most likely sources of the fluids that have formed epithermal Au–Ag ores in the KVB deposits.

Results of ultrasonic testing of parts that are fabricated by selective laser melting are assessed using radiography and X-ray computed tomography. Peculiarities of revealing incompletefusion flaws with the above methods are considered.

Possibilities and peculiarities of ultrasonic testing of parts manufactured by selective laser melting are considered. Special features of revealing solidity violation flaws with ultrasonic echo-pulse method are demonstrated.