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A non-equiatomic high-entropy alloy (HEA) CoCrFeNiAl coating on the 5083 alloy substrate is produced by wire-arc additive manufacturing (WAAM). It is revealed that microhardness changes significantly at the contact zone of the "coating — substrate" system. The changes range from 7.6 GPa at the coating boundary and the contact zone up to 1.6 GPa at the substrate boundary and the contact zone. The coating and substrate have the microhardness values of 6.3 GPa and 1.1 GPa, respectively. The structural phase state, defective structure, and elemental composition of the “coating — substrate” system are analyzed using methods of modern physical material science. It is shown that they depend on the distance from the contact zone between the coating and substrate. Also, it is found out that application of the high-entropy coating on the 5083 alloy surface is accompanied by mutual alloying of the coating and substrate. Creation of two types of submicro- and nanosized particles is revealed in the study. Nanosize particles of Al2O3 and MgAlO oxides, Al and HEA subgrains form the first structure. The second structure consists of nanosized HEA subgrains, Al13Fe4 and (NiCo)3Al4 nanoparticles located along the grain boundaries.

Сatagenetic transformations of asphaltenes of organic matter (OM) from recent sediments and fossil rocks were studied on rocks sampled from different sedimentary basins (Timan-Pechora, Mezen, West Siberian, Kuznetsk, Aldan-Maya and Middle Amur) of Russia. Changes in the elemental composition of asphaltenes were analyzed with the Veselovsky’s model of the formation of major groups of fossil fuels using cO parameter (cO = (O/8 – N)/(C/3)) as compared with the total carbon based on elemental analysis. Just as the Van-Krevelen diagram, the plot built in C–cO coordinates for OM of various genetic forms demonstrates a significant difference in the asphaltenes composition evolution during catagenesis. At the same time, the cO parameter has notably increased in asphaltenes of both types of OM. Structural transformations of asphaltenes during catagenesis were identified in the course of high-resolution NMR (nuclear magnetic resonance) spectroscopy. The research results comprise data on carbon distributions in the aromatic and aliphatic groups in the investigated asphaltenes of different type OM of sediments and rocks at different stages of lithogenesis. A correlation between the asphaltene composition and structural parameters depending on thermocatalytic transformations is revealed. The asphaltenes of terrestrial organic matter are distinguished by higher cO values and different carbon yields of aromatics (higher) and aliphatics (lower) throughout the catagenesis phase. The highly transformed marine OM is marked by surge condensation of aromatic rings in asphaltenes, which makes them similar to asphaltenes of the terrestrial type OM.

The evolution of the elemental composition of dispersed organic matter (DOM) heterocyclic components during catagenesis was traced via studying samples from the Tyumen (SG-6) and Srednevylyuy-27 (SV-27) super-deep wells of Siberia. During mesocatagenesis, the composition of terrigenous DOM asphaltenes and resins undergoes directed changes: a decrease in hydrogen and oxygen content, enrichment with carbon, and graphitization of the structure. During apocatagenesis, due to high-temperature destruction, on the one hand, there is a condensation of individual blocks of asphaltenes and their transition to an insoluble form (formation of epiasphaltenic kerogens – EPAK). On the other hand, the lighter part of the asphaltenes goes into the formation of hydrocarbons and gas formation – a relative increase in the concentration of the former in % by mass of residual bitumoids is noted, as well as structural redistributions within benzene and spirit-benzene resins. In all studied parameters of the elemental composition, a symmetrical (unidirectional) transformation of resinous and asphaltene components of bitumoids from the SG-6 and SV-27 wells under harsh thermobaric conditions is noted. The obtained results should be taken into account when predicting new oil and gas accumulation zones in deep-laid horizons.

Relevance. The need to expand the mineral resource base of the Trans-Baikal Territory. Aim. To study the geochemical composition of technozems of tailings dumps of gold deposits of the Trans-Baikal Territory, their correspondence, in terms of gold content, to technogenic deposits, to calculate the exceeding the maximum permissible concentrations of toxic elements in technozems of tailings dumps. Objects. Technozems of tailings dumps of gold deposits of the Trans-Baikal Territory. Methods. Silicate, X-ray fluorescence ISP-AES methods in analytical laboratories of the Geological Institute of the SB RAS (Ulan-Ude) and JSC "SGS Vostok Limited" (Chita). Results. It was found that in terms of gold content (Au>0.4 g/t), the technozems of the tailings of the gold deposits of the Trans-Baikal Territory, in general, correspond to technogenic gold deposits. The largest volumes and contents of gold (1.2 g/t) are characterized by technozems of the Baleysky tailings dam deposits with insignificant gold contents are technozems of Darasunsky (0.36 g/t) and Kariysky (0.35 g/t) deposits. It is determined that the chemical composition of the technozems of the tailings depends on the composition of the host rocks developed in the areas of deposits. They correspond to the rocks of both basic and medium compositions. The distinctive features of the content of impurity elements in the technozems of tailings are due to the different compositions of the initial ores of gold deposits. These differences are reflected in the values of exceeding the maximum permissible concentrations relative to soils. Among the toxic elements, arsenic is characterized by maximum exceedances of the maximum permissible concentrations. In the technozems of the Lyubavinsky deposit, the excess of the maximum permissible concentrations of arsenic relative to the soil is 933 times, and the Baley deposit is 397 times.

The processes of formation of films of alloys of the Cr–Ni, Cr–Ni–Si and Fe–Ni systems with a stab le elemental composition by evaporation methods are considered. It is shown that due to the large difference in the melting temperatures of Ni and Cr, nichrome films are obtained by sublimation. The design of the evaporator is proposed, which makes it possible to stabilize the composition of the films. Calculations of azeotropic compositions of alloys of the Cr–Ni–Si system have been carried out. The position of the isobars of the total pressure of iron and nickel on the state diagram was determined during evaporation in vacuum. The azeotropic composition of the alloy of the Fe–Ni system was calculated and experimentally verified.

The article proposes a model for predicting the content of metal components of complex oxide films deposited by reactive magnetron sputtering of a two-component composite target in Ar/O2 gas mixture. The model takes into account the sputtering yield and ion-electron emission coefficients of the sputtered metals and their oxides, the distribution of the ion current density on the target, and the rate of the chemical reaction of the formation of oxides of these metals. To verify the proposed model, studies of the elemental composition of titanium-aluminum oxide films deposited by magnetron sputtering of a Ti-Al composite target in Ar and Ar/O2 gas mixture were carried out. It has been established that the model adequately describes the change in the content of metals in the deposited films with a change in the oxygen flow into the chamber. The simulation error does not exceed 10 %, this makes it possible to use the proposed model for predicting the content of metals in a film during reactive sputtering of two-component composite targets.

Brown seaweeds (Laminariaceae) vary considerably in the content of toxic and essential elements; these variations depend on the taxonomic group and geographical factors. Seaweeds are extensively used in the food industry and widely applied in medicine for both humans and animals. Therefore, it is relevant to examine the correlation between the elemental composition and the geographical origin of kelp thalli obtained from different sources.The aim of the study was to collect, collate, and analyse primary and secondary data on the accumulation of essential, toxic and potentially carcinogenic elements, including iodine, in the thalli of brown seaweeds (Laminariaceae).Materials and methods. This study investigated the concentrations of 17 elements in Laminaria spp. (Al, As, Cd, Cr, Co, Cu, Fe, Hg, Mn, Mo, Ni, Se, Pb, Sr, V, Zn, and I). Experiments were conducted on an Agilent 7900 inductively coupled plasma mass spectrometer. The authors studied publications on the elemental composition of brown seaweeds (Laminariaceae) using literature search and data analysis methods.Results. This article reflects the updated classification of brown seaweeds (Laminariaceae) and summarises information about the mechanisms by which iodine and other elements accumulate in the thallus. The authors established species-specific variations in the order of element uptake and in the accumulation of elemental toxicants. The mutual influence of elements on their accumulation in brown seaweeds (Laminariaceae) was evaluated using Spearman’s rank correlation coefficients.Conclusions. The study results can inform the implementation of a risk-based quality control strategy for herbal medicinal products aimed at reducing human exposure to toxic elements. The authors suggest that the upper limit of iodine content in kelp-based food products should be standardised.

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The article features the elemental composition of copper and bronze sickle-shaped tools of the Tagar culture. The structure and composition of metal sickles have been the focus of chemical and spectral quantitative analyses since the 1950s. The paper introduces new data obtained by X-ray fluorescence, energy dispersive, and atomic emission spectral methods. The chemical and chemical-metallurgical features of the alloys add to the external descriptions of the Tagar metal tools. The research objective was to identify the features of Tagar copper-bronze sickles based on the chemical-metallurgical profile of the alloys. The authors also analyzed the effect of the alloy formulations on the morphological and metric characteristics of the tools, compared the bronze formulations with surface patterns, and established the copper ore sources. The study revealed no relationships between the bronze formulations and the morphological and metric indicators. An attempt to search for correlations showed two types of sickle-shaped tools. By measuring the length of the base and the height of the blade, the authors restored the actual sickles and reaping knives. The second type tools came from the Mariinsk-Achinsk foreststeppe. An analysis of the geochemical impurities in high-concentration copper indicated that the ore used in the Tagar tools was similar to that mined in the Glafirinsk and Kharadzhul-Butrakhty mines in the eastern foothills of the Kuznetsk Alatau. The sickle-shaped tools might also have been used to harvest fodder for livestock.

The elemental composition and structure of humic acids in the soddy-podzolic heavy loamy soil of the Cis-Urals were studied during long-term application of organic, mineral and organo-mineral fertilizers under conditions of a long-term stationary experiment. Mineral fertilizers contributed to the formation of humic acids with increased content of aliphatic components, the ratio H : C = 1.45 and a high degree of oxidation (ω = 0.41). The low content of nitrogen in humic acids (from 2.0 to 2.6 at.%), with various fertilizer systems, is primarily due to its low content in the plant biomass of crops cultivated in crop rotation.The organic fertilizer system resulted in the enrichment of the structural aggregates of humic acids with aromatic groups and nitrogen. The high intensity of absorption of the >C=O group of carboxylic acids in the region of 1 717 cm-1 and double bonds of carbon atoms at 1 627 cm-1 confirms this position. Humic acids of the “manure 10 t/ha” and “manure 5 t/ha + equiv. NPK” have the largest number of carboxyl groups in their composition. The vibrations of the >C=O group of carboxylic acids are most weakly expressed in soil humic acids with a mineral fertilizer system. Organo-mineral fertilizer system demonstrates intermediate results in terms of the content of the main constitutional elements in humic acids. Mineral fertilizers application reduces the amount and thermal stability of the structural components of humic acids, thereby contributing to the degradation of the most stable part of macromolecule, which can lead to the loss of potential soil fertility. Тhe use of mineral fertilizers on sod-podzolic heavy loamy soil led to the enrichment of humic acids with aliphatic fragments, and of organic ones – increased the content of stable components of aromatic nature, but lowered their thermal stability. According to thermographic analysis the ratio of weight loss in the low-temperature zone and the weight loss in the high-temperature zone (Z) during long-term use of mineral fertilizers is 0.9, i. e. the proportion of components of aliphatic nature in the structure of humic acids increases in comparison with unfertilized or manure fertilized soil.

Existing international legal acts, instruments and procedures do not guarantee equal conditions for the exploration and use of outer space. There is a need for means of objective control of spacecraft carrying products with fissile materials. Inspection of such objects can be carried out by X-ray fluorescence methods. However, in the subject area under consideration, the use of such methods has been little studied. In this paper, a method is proposed for obtaining the spectra of X-ray fluorescence radiation of materials, the object under study based on the calculation of the spatial and energy characteristics of X-ray radiation. The X-ray fluorescence spectra of objects are obtained on the basis of the calculation of the spatial and energy characteristics of X-ray radiation according to the original geometric (mathematical) and simulation models developed by the authors. The calculations take into account the complex layered system of the object, taking into account the proportions of high-energy fluorescent radiation of the overlying layers. An original numerical experiment is proposed using a program that allows one to choose the projections of an object subjected to X-ray irradiation, the wavelength and intensity of the emitter parameters. Using the obtained spatial-energy distribution of radiation quanta and the physical properties of the radiation transmission medium, the problem of finding the coordinates and angles of intersection of tracks of quanta beams in each area of the object is solved. The result of software processing is displayed as the resulting spectrum. The obtained spectrum makes it possible to draw a conclusion about the chemical composition of the materials of the inspected object. The X-ray beam reaching the object is modeled as a spot with an area commensurate with the cross section of the device in the form of a selected geometric primitive — a square. The spot area of the incident photons is calculated from a predetermined divergence angle. On the basis of open literary sources, a physical model of an object with nuclear fissile materials W88 (USA) was chosen. The following characteristics of X-ray beams (subbeams) are accepted: a coherent beam of photons with a wavelength of 0.005 nm; beam scattering angle of 1 degree; emitter detector area of 4 m2. The resulting X-ray fluorescence spectrum was obtained which gives an idea of the chemical composition of the units and blocks of the apparatus and the object inside. The presence of specific products on the object board is confirmed by characteristic lines with normalized wavelengths indicating the presence of chemical elements belonging to the radioactive series. The results obtained can be used in the development of hardware and software for spacecraft devices that monitor the presence of fissile materials on board of the inspected vehicle.

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The goal of the work was to study the microstructural, elemental, and electromagnetic properties of the samples of micropowder made from a natural mineral schungite. It was found that according to an X-ray spectral microanalysis, the carbon content in the studied samples of the mineral schungite was from 44 to 54 wt% while the iron content did not exceed 3.9 wt%. The iron content increased up to 6.1 wt% in the produced schungite micropowder. It can be presumed that in the schungite, micropowder iron exists in the form of ferrimagnetic nanoparticles of magnetite and pyrite, which is formed when grinding schungite particles in ball mills with a steel body and a milling bowl. The produced schungite micropowder also showed the presence of weak ferrimagnetic properties according to the measurements of magnetic permeability performed by vector analysis of the impedance of electrical circuits. In accordance with its electromagnetic characteristics, schungite micropowder made from shungite mineral is an effective radio-absorbing filler for building materials for cellular communication frequency bands

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The relevance of the study is caused by the need in data on the soil background states in the territory of the gold ore facility as well as in knowledge of relationships between the mineral and geochemical features of the deposit soil cover. The purpose of the research is to detect mineralogical and geochemical features of the soil cover of Vyun gold deposit territory at the pre-operational period of its development. Object of the study is soils of the territory of Vyun gold deposit. Factual materials and research methods. The factual material was obtained by employees of the Department of Geoecology and Geochemistry of the National Research Tomsk Polytechnic University in 2017 in the course of research work. The paper presents results of the study of the Vyun gold deposit territory based on 19 soil samples obtained at that time. The work was carried out by standard methods in accordance with the regulation documents. The elemental composition of the soils including 55 chemical elements was determined by the mass spectrometry method with inductively coupled plasma at the analytical chemical certified center «Plasma» (Tomsk). Mineral composition of soils was determined using optical microscopy, X-ray diffractometry and scanning electron microscopy on the basis of the International Scientific and Educational Center «Uranium Geology». The results were processed using modern software (Microsoft Excel, Statistica, Corel Draw, etc.). Results. The mineralogical and geochemical features of the soils in Vyun gold deposit territory have been determined. The relationship between the mineral composition of the ore zone and the soil geochemical characteristics was established. The data were obtained on the increased contents of gold and elements-satellites of low-sulfide gold-quartz mineralization, namely arsenic, silver, antimony, their contrasting scattering halos were determined, which can be used in the practice of further prospecting work.

Background. The article describes the processing technology and the results of studying the morphology, elemental composition, X-ray phase analysis and microhardness of the surface of stainless steel samples subjected to preliminary air-abrasive treatment and subsequent laser pulse alloying in a two-component coating layer consisting of graphite paste and titanium dioxide (anatase) powder. The purpose of this work is to identify the most rational modes of laser pulsed alloying of stainless steel 12Cr18Ni10Ti with an alloying coating preapplied to the treated surface. Materials and methods. The prototypes were plates made of stainless chromium-nickel steel 12Cr18Ni10Ti. Experimental studies were carried out using an abrasive blasting apparatus, an ultrasonic bath, an automated installation for thermophysical coherent surface modification “LRS-50A”. Results. A mechanism for increasing the microhardness of the surface of prototypes made of stainless chromium-nickel steel has been established and experimentally confirmed, which consists in the diffusion of alloying elements of the coating, saturation of the surface layer of steel with them during reflow under laser exposure, which in turn leads to the formation of new phases. Conclusions. A technology has been developed for thin-layer modification of the surface of stainless chromium-nickel steel by laser pulsed alloying using a special coating. The results of the work can be used with high efficiency at engineering enterprises that develop and produce critical parts and mechanisms that operate under conditions of intense gas and hydroabrasive wear.

The present article introduces an elemental composition analysis of copper and bronze alloys from the burials of the Lepeshkinsky Stage of the Tagar culture, burial site Serebryakovo I in the Kiya-Chulym interfluve. The research featured mounds 2, 12, and 16, which date back to 3–1 centuries B.C. The metal composition of 72 items was investigated by inductively coupled plasma atomic emission spectroscopy (ICP AES). The obtained data were subjected to statistical processing, which revealed seven chemical-metallurgical and metallurgical groups of copper-based alloys. The bronze alloys did not depend on the typology of the tools, i.e. knives, engravings, mirrors, deer plaques, etc. The results confirmed the dating of the Lepeshkinsky site between the Saragashensky and the Tesinsky Stages of the Tagar culture. The items revealed a tendency towards a decrease in the proportion of tin bronzes and average concentrations of tin ligatures. The study proved that archaeometallurgical data can help to determine the relative-chronological position of the Tagar culture burial complexes.

The paper discusses a ceramic bricks from Uvek settlement using the results of field and laboratory studies of 1998–2020. The goal of the research was to define the physico-technical characteristics of bricks from Uvek settlement for historico-architectural, technical and economic substantiation of the construction technologies of the Golden Horde, for reconstruction and restoration work, for computer modeling in virtual and augmented reality systems. The paper presents data on the diverse shapes and dimensions of the bricks, and the imprints on its surface. It discusses the results of studies aimed at establishing the elemental composition of the ceramic material using the Auger method and secondary ion mass spectroscopy (SIMS) to identify the raw material mining sites. Data is provided on the average density of the brick, its group in terms of thermal characteristics, emissivity coefficient, water absorption by weight, ultimate compression and bending strength, and its brand in accordance with the parameters regulated by the state standard in effect.

The relevance of the research is justified by the need in data on the state of natural surface waters in the territories of gold mining enterprises located in the permafrost zone of the subarctic belt. The purpose of the research is to identify the geochemical properties of natural waters in the territory of Vyun gold deposit at the stage of pre-production development. Object: surface waters of the Vyun gold deposit. Factual materials and research methods. The factual material was obtained as a result of research work carried out in 2017 by the Department of Geoecology and Geochemistry of National Research Tomsk Polytechnic University. This paper discusses the study of watercourses in the territory of Vyun gold deposit on the basis of 13 water samples taken in the area. The samples were taken and processed using standard methods in accordance with regulation documents. The elemental composition of water was determined in the accredited Problems Research Laboratory of hydrogeochemistry of the Scientific and Educational Center «Voda» of the National Research Tomsk Polytechnic University. Contents of 71 chemical elements were determined by the method of inductively coupled plasma mass spectrometry. A number of methods were used for establishing the hydrochemical characteristics of the waters.More specifically the samples were analyzed by following methods: titrimetric; potentiometric; conductometric; gravimetric; photocolorimetric; spectrophotometric; by ion chromatographic. The calculation methods and codes developed in Scientific and Educational Center «Voda»were used as well. The results were processed using Microsoft Excel and Statistica. Schemes and diagrams were performed by the graphics editor Corel Draw. Results. The geochemical features of the natural watercourses of the Vyun gold ore deposit area under permafrost conditions were specified.The presence of contrast anomalies of chemical elements represented by arsenic and mercury was established. These elements are satellites of low-sulfide gold quartz mineralization.

Relevance of the work is caused by the need to study the environmental consequences of long-term transboundary transport of pollutants from industrial centers of East Kazakhstan to the Altai region and Altai Republic. The main aim of the research is to study the elemental composition and features of its distribution in the epilitic lichen Rhizocarpon geographicum (L.) DC. on stone as a biogeochemical indicator of the specificity and intensity of transboundary transport of pollutants to the Altai territory. The methods: selection of samples of lichen Rhizocarpon geographicum (L.) DC. on rock outcrops of lower Paleozoic terrigenous rocks to determine the content of mercury and 28 chemical elements by atomic absorption and instrumental neutron activation analysis, processing the data by methods of applied statistics. The results. The authors have obtained the data on the levels of content and distribution characteristics of the complex chemical elements in the lichen Rhizocarpon geographicum (L.) DC. on stone on the territory of Altai. They were compared with the regional background and Clark in the biosphere. The presence of two groups of elements in the lichen – trace elements of inorganic dust and the Association of elements of polymetallic ores (Zn, As, Sb, Br, Hg, Au) was established. The argument in favor of the predominant receipt of elements of this Association in the lichen Rhizocarpon from atmospheric deposition transferred from the territory of East Kazakhstan was given. The authors identified the large area of elevated concentrations of the studied elements in Rhizocarpon, spatially coinciding with the previously established area of snow and vegetation contamination in the region. They made the conclusion on suitability of the elemental composition of epilitic lichen Rhizocarpon on stone as a biogeochemical indicator of the specificity and intensity of transboundary transport of pollutants to the Altai territory.

The relevance of the research is in poorly studied mineralogical, elemental composition and toxicity of drill cuttings formed during the construction of wells in oil fields. The main aim of the research is to identify the geochemical and mineralogical particularity of drill cuttings, to determine the toxicity of this type of waste using modern research methods. Methods: X-ray powder diffraction; inductively coupled plasma mass spectrometry; scanning electron microscope; bioassay. Results. Common minerals, such as quartz, albite, muscovite and calcite, were determined in the studied samples of drill cuttings that indicates a similar composition of the original host rocks. The geochemical specificity of drill cuttings expressed in increased concentration of chemical elements such as Pb, Zn, Cu, was revealed. Mainly, the elements belong to heavy metals of I, II and III hazard class. The value of the total pollution indicator shows that most samples of drill cuttings are of low pollution. However, the samples from existing sludge pits are characterized by medium pollution. The identified mineral phases are represented by oxides of iron, lead, zinc, iron sulfide, barium sulfate. Spherical particles of iron and lead were discovered. In general, drill cuttings samples have not toxic effects on test objects: Daphia magna, Scenedesmus quadricauda, Drosophila melanogaster. At the same time, samples from existing sludge pits have an effect on the test organism Daphia magna. In this way, the studied samples of drill cuttings are low-hazardous, practically non-hazardous waste, and are not potentially toxic.

In a crisis, resources are often limited and it is only possible to save a business by transforming management. Synergics-managers are able to take the enterprise out ofthe crisis or not to admit it at all. In a synergistic organization it is possible to change the elementary composition and bring it to the desired state, thereby avoiding a crisis. Also, the organization must set a high-quality goalfor success in business. The management ofthe organization itself should contribute to the achievement ofthe goals.

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The scientific interest in the investigation of nitride composites as protecting materials in tool and machining industries intensively increases. The good oxidation resistance of CrN single-layer films and high melting point, good chemical and thermal resistance of ZrN compound are motive factors for designing of multilayer composites composed of these metal nitrides. The suggested advantages of ZrN/CrN multilayer coatings as structural materials are the high-temperature resistance, high density and extreme hardness compared to the metal-nitride systems. Experimental ZrN/CrN multilayer coatings were deposited on AISI 321 steel substrates by using a cathodic arc evaporation device equipped with two high-purity metal Cr and Zr targets. Structural, chemical and morphological characteristics together with mechanical properties of multilayer composites were analyzed by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy and Vickers hardness tester. SEM analysis revealed an increase of roughness and concentration of the droplets on the surface of the coatings when negative bias potential decreased to -70 V. The results of data obtained from the X-ray analysis showed (200) and (111) plane for ZrN and Cr2N phases as the most intense. The peak positions of ZrN were shifted towards lower diffraction angles comparing with bulk values and indicated a decrease of the inter-planar distance and formation of compressive stresses. The calculated lattice strain values in the ZrN were higher than those of the CrN, indicated a greater presence of dislocations and defects in the lattice of ZrN. The averaged crystallite sizes in ZrN and CrN layers were 11-14 and 7-12 nm, respectively. The maximum value of the Vickers microhardness was found to be 6600HV0.01 that is 2.1 and 1.8 times greater than the corresponding values of binary CrN and ZrN coatings.

Based on the data from the marine researches of Knipovich Polar Research Institute of Marine Fisheries and Oceanography (PINRO) carried out in the period of 2010–2015, the content of some metals in bottom sediments of the central part of the Pechora Sea has been analyzed at 99 stations. The particle size distribution and pH of the surface layer of sediments have been investigated. No interannual changes in the studied parameters have been revealed. According to the studies conducted, the predominant form of bottom sediments is fine sand, occasionally sandy loam has been found. Comparison of the average relative content of the number of studied trace elements in the Pechora Sea bottom sediments with those ones of the White Sea and the Upper Continental Crust (UCC) standard has not revealed any fundamental differences. It has been shown that Pb and Cd content is the most variable in the bottom sediments. The median values of the concentration factors of all the studied trace elements in the Pechora Sea sediments, normalized by UCC, are noticeably less than 1. The diagrams of the position of the relative content points of the studied elements pairs in the Pechora Sea sediments have been graphed and analyzed. These diagrams have been compared with those ones for the corresponding pairs of elements in the sediments of the Chukchi and East-Siberian Seas and certain differences have been revealed that are most noticeable with respect to the Pechora and East-Siberian Seas. The relative similarity of the composition of the Pechora Sea to the Chukchi Sea bottom sediments has been found. The data on statistical processing of the average contents of all the studied metals in the bottom sediments are given. No noticeable differences from the results of previous studies in the Pechora Sea have been found. Correlation analysis of the content of trace elements has been performed. Analysis of the data presented has not revealed anthropogenic contamination in the bottom sediments of the Pechora Sea with heavy metals; as a result, background levels for the Pechora Sea bottom sediments have been recommended for Cu, Zn, Ni, Cr, Pb, Cd and Hg

Copyright of Eurasian Journal of Ecology is the property of Al-Farabi Kazakh National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Superelastic alloys of titanium (titanium-niobium-zirconium and titanium-niobium-tantalum) are more favorable in comparison with titanium for dental implants due to their physico-mechanical properties closer to those of bone tissue. Animal morphological studies of the biocompatibility of these alloys in comparison with titanium have been carried out. The control of the titanium alloy samples interaction with bone tissue was performed at the time points of 30 and 90 days; scanning electron microscopy and microprobe element analysis of tissue along the boundary with titanium alloys were used as the methods of investigation. The proximity of the morphological pattern and elemental composition of bone tissue along the border with titanium and superelastic alloys of titanium is shown, both at the control period of 30 days (in contact with alloys, a poorly mineralized connective tissue is found) and at 90 days (the border with titanium alloys is covered with mineralized bone tissue, similar in its composition to the surrounding bone tissue).

The range of content of a number of essential macro- and microelements, as well as non-essential and toxic elements in a 3-leaf flush of Colchis tea (raw material) grown in the conditions of the Black Sea coast of Russia has been established. The content of the main macronutrients was within (in% of abs. dry sub.): N-3.80-5.44; P-0.38-0.56; K-1.55-1.78; Ca-0.14-0.24; Mg-0.19-0.22. The content of micro- elements was (in mg / kg): Mn - 423-856; Fe - 28.8-52.2; Zn 29.6-45.8; Co-0.11-0.27. The content of non-essential and toxic elements varied in the following ranges (in mg / kg): Al -114-349; Si-25.4-98.2; Na-6.57-19.02; Ba-3.25-8.83; Ni-5.49-12.24; Pb-0.32-3.95; Ti-0.27-1.11; V-0.042-0.060; Li-0.04-0.08; Cr-0.13-0.30; Cd is 0.01-0.03.

The paper presents results of studying structure and properties of multilayer composite coatings optimized for their composition based on zirconium dioxide materials used for deposition of plasma coatings on the models of elements for anti-meteor shielding screens. The influence of plasma jet parameters (current, distance of sputtering, consumption of plasma-forming nitrogen gas) and fractional composition of an initial powder on characteristics of two-layer composite coatings based on nickel-chromium-aluminum-yttrium and zirconium dioxide on the elements of protective screens has been analyzed in the paper. Optimization has been carried out on the basis of obtaining maximum coefficient of powder utilization. The investigations have made it possible to ascertain specific features of elemental and phase composition, surface morphology, microstructure multilayer composite coatings on the basis of a solid layer of metal oxides and a viscous transition sub-layer subjected to compression plasma flows. The investigations have been executed with the help of scanning electron microscopy, energy dispersive x-ray spectral microanalysis, and x-ray diffraction analysis. It has been shown on the basis of the obtained results that the effect of compression plasma flows on multilayer composite coatings leads to a modification of a near-surface layer with a thickness up to 15 μm that presupposes its melting and subsequent high-speed crystallization which together provide an increase in its density, decrease in porosity while maintaining the initial phase state. Liquid-phase processes in the molten phase of the near-surface layer permit to modify morphological properties of the surface which are associated with its smoothing and lowering of roughness.

The study of the elemental composition of samples of vanadium dioxide is used as a thermal sensor in logging complexes after a series of 0, 15, 30, 50 thermal cycles. The influence of thermal Cycling on the elemental composition of the surface of vanadium dioxide and the electrical properties of VO2 in the vicinity of the phase transition is studied. There is change in the electrical properties of the material in the phase transition metal– semiconductor. It is revealed that the value of the electrical resistivity jump at the phase transition is significantly less for the sample, after a series of 50 thermal cycles compared with the original sample.

The article presents the detailed analysis results considering bottom sediments from the Chukchi Sea. Two core samples, b16 and НС–8 were taken from the northern Herald Canyon 150 km northeast from NE Wrangel Island. Core b16 has been studied in more detail. According to the 210Pb measurements, the recent sedimentation rate amounts to 0.9 mm/y–1 at the sampling point. In the bottom layer of the core sample, the minimum concentrations of biogenic components (SiO2bio, Corg, Ntot, and Br) and the increased concentrations of cold-water diatom species Thalassiosira antarctica may result from low biological productivity during the Maunder Minimum. A correlation with recent global warming (11–22 years) is shown by the increased concentrations of SiO2bio, Corg, Ntot, and Br and the decreased values of magnetic susceptibility and X-ray density in the top layer (1–2 cm) of the same core sample. The results of our geochemical and diatom analysis support the available literature data and confirm that the Late Holocene sedimentation in the Chukchi Sea takes place in the zone wherein the water transits from the Pacific to the Arctic Ocean.

Corrosion properties of coatings based on Ti1-xAlxN precipitated by pulsed magnetron sputtering were studied. The effect of phase composition, aluminum content in Ti0,40Al0,60N and Ti0,62Al0,38N coatings on their electrochemical characteristics obtained in 0,3% NaCl solution was established.

The method of recycling secondary energy resources - oil-contaminated sludge chemical water treatment. Experimentally determined ash content, calorific value of oil-contaminated sludge. The technology for efficient combustion of polluted sludge on small power plants.

Studied the elemental composition of the fuel oil, derived from petroleum different fields; The values of the density, content and total sulphide sulfur and calorific value of the test fuel oil.

Relevance of the work is caused by the need to assess and monitor the ecological condition of atmospheric air in Gorno-Altaisk as the most urbanized area of the Altai Republic. The main aim of the study is the research of chemical composition and characteristics of distribution of elements in the lichen Caloplaca sp. (scale) on the slate as a bioindicator of the specificity and intensity of anthropogenic activities in Gorno-Altaisk. The methods: lichen Caloplaca sp. (scale) and conjugate slate sampling from the roof of buildings, determination of content of 28 chemical elements using instrumental neutron activation analysis, processing and interpretation of the data obtained by the methods of applied statistics. The results. The authors have obtained the data on the levels of contents of chemical elements in the lichen Caloplaca sp. (scale) on the slate near Gorno-Altaysk and compared them with local background and clarke in the biosphere. Close relationship between the elements of As, Sb, Cr, Zn, Ba, Br, Co, Fe, U association, rare earth elements in lichen, as well as their level of concentration and content in coals of the Kuznetsk basin was determined. The paper introduces the argument in favor of admission of these elements in the lichen Caloplaca sp. from atmospheric air. The authors revealed the scope of their elevated concentrations in lichen, spatially coincident with areas of high dust load within the Metropolitan area. The conclusion is made about the possibility of using the elemental composition of the epilithic lichen Caloplaca sp. on the slate for bioindication of specificity and intensity of anthropogenic activities, as well as an additional indicator for monitoring the condition of surface atmosphere of the settlements within Gorno-Altaisk area.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Relevance of the work is caused by the need to utilize a large amount of husk formed at rice processing. The aim of the research is to determine the composition and structural characteristics of the solid carbon materials obtained by heat treatment of husk of rice grown in the Red River Delta (Republic of Vietnam). Methods: method of heat differential scanning calorimetry using a simultaneous thermal analyzer STA 449F3 Jupiter (Netzsch, Germany) combined with mass spectrometer QMS 403C Aёolos (Netzsch, Germany); electron microscopy (JEOL USA JCM-6000); ZAF method standardless quantitative analysis to determine the elemental composition; isotherm of hermal nitrogen desorption by using NOVA Station A device in accordance with the BET method and according to GOST 6217-74 to determine the porous structure characteristics (specific surface area - S, total pore volume - V[sigma], pore diameter - d). Results. Calcination of raw material at the temperature of 600 C results in significant decrease in oxygen content from 42,82 to 26,17 wt.%, increase in silicon content from 7,00 to 25,00 wt. %; the C/H ratio increases to 30 expectedly. Elemental composition and parameters of porous structure of rice husk, carbonizate, material after separation of SiO2 and activated carbon were investigated. Activation of the resulting material containing 10 wt. % of potassium carbonate at 900 C let obtain the activated carbon with specific surface area of 1329 m2/g and adsorption capacity of 0.811 cm3/g. Contribution of micropore surface to the specific surface area increases up to 60 % as a result of the carried out operations. The calculated C/H ratio reaches 84.

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The relevance of the research is supported by the necessity to elaborate the criteria for assessing the environment condition. Biogeochemical study of all objects and components of the biosphere is rather relevant task of modern times. Local technogenic transformations of areas cause spontaneous, irregular income of elements to the living organisms. Study of element composition of human hair proved itself to be good for assessing this income degree. Human hair is a deposit environment and can serve as an indicator for anthropogenic change of the environment. The aim of the study is to investigate the accumulation specificity of chemical elements in the content of childrenґs hair under the influence of technogenesis and to find the indicators of this influence. The research methods: instrumental neutron activation analysis (quantitative determination of 29 chemical elements), mass-spectro-metry with inductively coupled plasma ICP-MS. Results. The authors have determined the peculiarities of formation of element composition of childrenґs hair (3-18 years old) in the area of Northern industrial hub of Tomsk. For this purpose, the investigated area was divided into sectors taking into account the prevailing «wind rose» (the axes were run across Tomsk). The first sector - the north-north-eastern - is subject to the most influence of technogenesis; in comparison with other sectors it is characterized by the maximal accumulation of Sc, Cr, Zn, Lu, Hf, Au, Th, U, Cs in hair. The second one, the eastern sector, in comparison with the others is distinguished by the maximal accumulation of Se, Yb, Ag, Eu with concentrations, which are higher than average regional values. The third, western, sector is characterized by the highest Sb accumulation level. The fourth one, the southern sector, can be considered as the background sector with low concentrations of the most studied elements. In addition, the authors compared smth with the data on chemical elements content in the hair of Seversk and Tomsk residents. The investigation shown that Seversk, compared to other areas, is characterized by the maximal accumulation of Br, Ta, U and Ce. For the hair samples from Tomsk, La, Sm and Eu are specific. In the villages, located near tailings, the accumulation level of elements 6,5 times exceeds the background level. For the hair from both villages, the high level (2,5 times exceeds the background) of Au, Ag, Tl, Re, Eu, Li contents is specific. Conclusions. The element composition of childrenґs hair in the studied area reflects the specificity of technogenic influence of different manufacturing enterprises in Northern industrial hub of Tomsk; and in general, it is formed under the additive effects of natural and technogenic aspects. In the areas with the most active technogenic impact, the concentrations of element in the hair are higher and the range of elements is wider in comparison with the average regional factors and background data. Urban territories are distinguished by Br and rare earth elements accumulation in childrenґs hair. Human settlements, which are not subject to the main impact of industrial enterprises and located in thirty-kilometer area of SCC impact, at prevailing direction of wind transfer of the substances, suffer the technogenic influence. The southern part of Tomsk district can be considered as background area with low concentrations of the majority of the studied elements. The indices of elements ratio are significant indicators of technogenesis conditions. Tomsk district as the most technogenic-transformed area is characterized by specific concentration of lanthanides in the childrenґs hair. In the territories with the stored wastes of enrichment production, the concentration of chemical elements, reflecting the specificity of the produced and recycled materials, is specific for childrenґs hair. Therefore, childrenґs hair is the demonstrating factor of technogenic load on the residential areas.

The Aim of the Study: Was to assess the possibility of using chemical analysis of bone mineral content by the means of an energy dispersive X-Ray spectroscopy to determine the age of unidentified corpses for forensic identification. A semi-quantative chemical microanalysis of bone fragments of 85 male and female corpses aged between 21 and 91 was done through the use of energy dispersive X-Ray spectrometer. The association of bone tissue apatite mineral composition with age is confirmed and a formula, connecting age and chemical composition change, is proposed. The possibility of using quantitive evaluation of chemical elements content in the normative mineral to determine the unidentified corpse's age in a standard laboratory, equipped with an energy dispersive X-Ray spectrometer, was proved.

In the proposed work conventional methods of SiC layers formation and polytypes of this compound have been reviewed. A new methodology of silicon carbide obtaining has been proposed. It is based on magnetron sputtering of compound targets. The optimal geometrical characteristics of the compound targets made of silicon and graphite have been calculated. The condensates structure and composition were studied with help of transmission electron microscopy (TEM), electron diffraction along with the energy dispersive X-ray elemental analysis. On the basis of the investigations the geometrical characteristics of the compound target and the optimal technological parameters required for the formation of silicon carbide in the form of 3C-SiC polytype with element composition close to stoichiometric have been determined. [ABSTRACT FROM AUTHOR]

In this paper by the methods of diffractometry, scanning and atomic force microscopy, X-ray characteristic radiation induced by focused proton beam (PIXE), Rutherford backscattering of helium-4 ions we have investigated Pb1 - xSnxS films obtained by "hot wall". It was found that layers obtained by condensation in the temperature range of Ts = (268-382) °C have virtually a single phase orthorhombic crystal structure with lattice parameters which vary in the range of a = (0.4214-0.4293) nm, b = (1.1246-1.1313) nm, c = (0.3980- 0.4015) nm. CSD sizes in the films are equal to L(040) = (35.5-47.5) nm, L(131) = (44.4-51.5) nm. The distribution of the components of a compound of films (μ-PIXE) and their elemental composition (PIXE) are determined. It was found that some samples were depleted by sulfur in comparison with the stoichiometric composition. Atomic concentration of the components of the solid solution varies in the range of CPb = 12.71-19.13; CSn = 40.29-44.46; CS = 38.36-42.75 at. %. By increasing the substrate temperature, the lead content in the films increases and the sulfur content decreases, the atomic concentration of tin in this case varies slightly. [ABSTRACT FROM AUTHOR]