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Deuterium retention in chemically vapor deposited tungsten carbide coatings and hot-rolled tungsten exposed to low-energy deuterium plasma

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Tungsten 2022年第1期4卷 10-19页

作者： vladimir Kh.Alimov Joachim Roth Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesMoscow 119071Russia max-Planck-Institut fur Plasmaphysik 85748 GarchingGermany

Samples of chemically vapor deposited(CVD)coatings of tungsten carbides W_(45)C_(55)and W_(60)C_(40)and samples of hot-rolled tungsten were exposed to deuterium(D)plasma at sample temperatures ranging from 323 to 813 K,as a result of which the samples were irradiated with D ions with an energy of about 200 eV per D particle at a flux of D particles of about1.1×10^(21)D·m^(-2)·s^(-1)to a fluence of about 2×10^(24)D·m^(-2).The concentration of deuterium in these samples was examined by the D(3 He,p)4 He nuclear *** on the measured deuterium depth profiles and assuming that these profiles are determined by diffusing D atoms,the diffusion coefficients of deuterium in the CVD tungsten carbide coatings were *** these diffusion coefficients,an estimate of the Arrhenius relation for the diffusion coefficients of deuterium in CVD tungsten carbide coatings was obtained:D=2.5×10^(-3)exp(-1.12 eV/kT)m~2·s^(-1),where T is temperature expressed in Kelvin,and k is the Boltzmann *** concentration of trapped deuterium in the bulk of CVD tungsten carbide coatings is practically independent of the stoichiometry of the *** decreases from about 5×10^(-2)to about 7×10^(-4)D/(W+C)with an increase in the deuterium plasma exposure temperature from 373 to 813 *** concentration of trapped deuterium in hot-rolled tungsten,expressed in units of the D/W atomic ratio,is more than an order of magnitude lower than the concentration of deuterium in tungsten carbides,and also decreases with increasing plasma exposure temperature.

关键词： Chemically vapor deposited tungsten carbides Tungsten Deuterium plasma Deuterium depth profiles Deuterium diffusion coefficients

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Latitudinal and temporal shifts in the radial growth-climate response of Siberian larch in the Polar Urals

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Journal of mountain Science 2018年第4期15卷 722-729页

作者： vladimir V.KUKARSKIH Nadezhda m.DEVI Pavel A.mOISEEV Andrey A.GRIGORIEV maksim O.BUBNOV Institute of plant and animal ecology UB RAS 8-Marta 202/3 620144 Ekaterinburg Russia

This paper presents a dendroclimatic analysis of Siberian larch trees sampled along a latitudinal 260-km transect located in the Polar Urals,Russia. Three standardised chronologies were built over a length of 230–293 years using 79 individual tree-ring chronologies collected in the southern,middle and northern parts of the Polar *** correlation functions showed that the annual growth of the larches was mainly influenced by the air temperatures in June and July. The relative role of the temperatures increased from south to north. Daily air temperature data analysis revealed that the duration of the growing season in the northern part of the Polar Urals is 24 days less than that in the southern part. At the present time, air temperatures exceeded threshold of 8~℃, 5 days earlier than it did in the beginning of the 20 th century In response to the increase in the duration of the growing season and the changing winter conditions in the Polar Urals over the last 130 years, radial growth–temperature relationships in larches have weakened;this effect was strongly pronounced in the southern part of the Polar Urals.

关键词： Tree rings Dendroclimatilogy Larix sibirica Growing season Polar Urals

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Pharmacological and Predicted Activities of Natural Azo Compounds

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Natural Products and Bioprospecting 2017年第1期7卷 151-169页

作者： Valery m.Dembitsky Tatyana A.Gloriozova vladimir V.Poroikov National Scientific Center of marine Biology 17 Palchevsky Str.VladivostokRussia 690041 Institute of Biomedical Chemistry MoscowRussia 119121

This paper describes research on natural azo compounds isolated from fungi,plant,bacteria,and *** than 120 biologically active diazene containing alkaloids demonstrate confirmed pharmacological activity,including antitumor,antimicrobial,and antibacterial *** structures,origin,and biological activities of azo compounds are *** the computer program PASS,some structure–activity relationship new activities are also predicted,pointing toward possible new applications of these *** article emphasizes the role of natural azo compounds as an important source of drug prototypes and leads for drug discovery.

关键词： Azo metabolites Alkaloids Fungi Plant Bacteria Sponges SAR

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Distribution and changes of active layer thickness(ALT) and soil temperature(TTOP) in the source area of the Yellow River using the GIPL model

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Science China Earth Sciences 2014年第8期57卷 1834-1845页

作者： LUO DongLiang JIN HuiJun Sergei mARCHENKO vladimir ROmANOVSKY State Key Laboratory of Frozen Soils Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Geophysical Institute University of Alaska FairbanksFairbanks Alaska 99775 USA

Active layer thickness（ALT） is critical to the understanding of the surface energy balance, hydrological cycles, plant growth, and cold region engineering projects in permafrost regions. The temperature at the bottom of the active layer, a boundary layer between the equilibrium thermal state（in permafrost below） and transient thermal state（in the atmosphere and surface canopies above）, is an important parameter to reflect the existence and thermal stability of permafrost. In this study, the Geophysical Institute Permafrost model（GIPL） was used to model the spatial distribution of and changes in ALT and soil temperature in the Source Area of the Yellow River（SAYR）, where continuous, discontinuous, and sporadic permafrost coexists with seasonally frozen ground. monthly air temperatures downscaled from the CRU TS3.0 datasets, monthly snow depth derived from the passive microwave remote-sensing data SmmR and SSm/I, and vegetation patterns and soil properties at scale of 1：1000000 were used as input data after modified with GIS techniques. The model validation was carried out carefully with in-situ ALT in the SAYR interpolated from the field-measured soil temperature data. The results of the model indicate that the average ALT in the SAYR has significantly increased from 1.8 m in 1980 to 2.4 m in 2006 at an average rate of 2.2 cm yr–1. The mean annual temperature at the bottom of the active layer, or temperature at the top of permafrost（TTOP） rose substantially from –1.1°C in 1980 to –0.6°C in 2006 at an average rate of 0.018°C yr–1. The increasing rate of the ALT and TTOP has accelerated since 2000. Regional warming and degradation of permafrost has also occurred, and the changes in the areal extent of regions with a sub-zero TTOP shrank from 2.4×104 to 2.2×104 km2 at an average rate of 74 km2 yr–1. Changes of ALT and temperature have adversely affected the environmental stability in the SAYR.

关键词： GIPL model active layer thickness TTOP degradation of permafrost

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Reconstructions of model equations of time-delay system from short experimental time series

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International Journal of modeling, Simulation, and Scientific Computing 2020年第2期11卷 91-99页

作者： Anatoly S.Karavaev Yurii m.Ishbulatov Ekaterina I.Borovkova Danil D.Kulminskiy vladimir S.Khorev Anton R.Kiselev vladimir I.Ponomarenko vladimir I.Gridnev mikhail D.Prokhorov Boris P.Bezruchko Department of Dynamic modeling and Biomedical Engineering Saratov State University 83 Astrakhanskaya Street Saratov410012Russia Laboratory of Nonlinear Dynamics modeling Saratov Branch of the Institute of Radio Engineering and Electronics of Russian Academy of Sciences 38 Zelyonaya Street Saratov410019Russia Department of New Cardiological Informational Technologies Institute of Cardiological Research Saratov State medical University 112 Bolshaya Kazachaya StreetSaratov410012Russia

This study aims to investigate the scope of methods for the reconstruction of time-delay *** consider an approach to the reconstruction of time-delay systems based on the synchronous response of the driven system with the structure similar to the structure of the studied *** approach is used for the recovery of the parameters of timedelay systems from short and noisy time *** show the operational performance and capabilities of this approach,the parameters were reconstructed for a radiophysical chaotic generator with quadratic nonlinearity and for the model of a system for the baroreflectory regulation of the mean arterial pressure.

关键词： Time-delay systems reconstruction chaos radiophysical experiment

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Euxinia as a dominant process during OAEla(Early Aptian)on the Eastern Russian Platform and during OAElb(Early Albian)in the middle Caspian

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Science China Earth Sciences 2017年第1期60卷 58-70页

作者： Svetlana O. ZORINA Oksana V. PAVLOVA Bulat m. GALIULL1N vladimir P. mOROZOV Alexey A. ESKIN Institute of Geology and Petroleum Technologies Kazan Federal University 4/5 Kremlyovskaya street Kazan 420008 Russian Federation

A detailed study of the mineral composition and microstructure of the black shales associated with OAE1 a （Eastern Russian Platform）, OAElb （middle Caspian）, and the host rocks has been carried out using X-ray diffraction, scanning electron microscopic, and microprobe analyses. The results provide important constraints for depositional environments in the sedimentary basins. Black shales with pyrite framboids imply euxinic （sulfidic） conditions with increased organic matter preservation. Disintegrating framboids suggest partial or complete dissolution of the organic matter inside the framboids due to increasing water oxygenation. OAEla on the Eastern Russian Platform is heterogeneous as it includes thin interbeds of concretionary coccolith limestones within the interval of bituminous shales, and correlates with the Lower Aptian Rhagodiscus angustus nannofossil zone. The coccolith limestones indicate short intermittent episodes of interrupted stagnation, rapid oxygenation, and restoration of normal marine conditions. The presence of montmorillonite, albite, microcline, and diopside in the bituminous siltstones and in the host siltstones of OAEla on the Eastern Russian Platform, as well as a high content of titanium in the black siltstones correlated with OAEIb in the middle Caspian allow proposing significant input of pyroclastic material into the extant sea.

关键词： OAEIa OAElb Black shales Pyrite framboids Euxinia Oxygenation Eastem Russian Platform middleCaspian Cretaceous

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Self-assembled formation of long, thin, and uncoalesced GaN nanowires on crystalline TiN films

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Nano Research 2018年第1期11卷 565-576页

作者： David van Treeck Gabriele Calabrese Jelle J. W. Goertz vladimir m. Kaganer Oliver Brandt Sergio Fernandez-Garrido, Lutz Geelhaar PauI-Drude-lnstitut f~r Festk6rperelektronik Leibniz-lnstitut im Forschungsverbund Berlin e.V. Hausvogteiplatz 5-7 I 0117 Berlin Germany

We investigate in detail the self-assembled nucleation and growth of vertically oriented GaN nanowires by molecular beam epitaxy on crystalline TiN films. We demonstrate that this type of substrate allows for the growth of long and thin GaN nanowires that do not suffer from coalescence, a problem common to the growth on Si and other substrates. Only beyond a certain nanowire length that depends on the nanowire density and exceeds here 1.5 bun, coalescence takes place by bundling, i.e. the same process as on Si. By analyzing the nearest neighbor distance distribution, we identify the diffusion-induced repulsion of neighboring nanowires as the main mechanism limiting nanowire density during nucleation on TiN. Since on Si the final density is determined by shadowing of the impinging molecular beams by existing nanowires, it is the difference in adatom surface diffusion that enables the formation of nanowire ensembles with reduced density on TiN. These nanowire ensembles combine properties that make them a promising basis for the growth of core-shell heterostructures.

关键词： nanocolumn gallium nitride nucleation metal substrate coalescence core-shell

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microbial processes and factors controlling their activities in alkaline lakes of the mongolian plateau

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Chinese Journal of Oceanology and Limnology 2015年第6期33卷 1391-1401页

作者： Zorigto B.NAmSARAEV Svetlana V.ZAITSEVA vladimir m.GORLENKO Ludmila P.KOZYREVA Bair B.NAmSARAEV National Research Centre "Kurchatov Institute" Akademika Kurchatova pl.1Moscow 123182Russia Winogradsky Institute of microbiology RAS Prosp.60-let Oktyabrya 7/2Moscow 117312Russia Laboratory of microbiology Institute of General and Experimental BiologySiberian branch RASSakhyanovoi St .6UlanUdeBuryat Republic 670047Russia Buryat State University Smolina21Ulan-UdeBuryat Republic 670000Russia

A striking feature of the mongolian plateau is the wide range of air temperatures during a year, -30 to 30~C. High summer temperatures, atmospheric weathering and the arid climate lead to formation of numerous alkaline soda lakes that are covered by ice during 6-7 months per year. During the study period, the lakes had pH values between 8.1 to 10.4 and salinity between 1.8 and 360 g/L. According to chemical composition, the lakes belong to sodium carbonate, sodium chloride-carbonate and sodium sulfate-carbonate types. This paper presents the data on the water chemical composition, results of the determination of the rates of microbial processes in microbial mats and sediments in the lakes studied, and the results of a Principal Component Analysis of environmental variables and microbial activity data. Temperature was the most important factor that influenced both chemical composition and microbial activity, pH and salinity are also important factors for the microbial processes. Dark CO2 fixation is impacted mostly by salinity and the chemical composition of the lake water. Total photosynthesis and sulfate-reduction are impacted mostly by pH. Photosynthesis is the dominant process of primary production, but the highest rate （386 mg C/（L.d）） determined in the lakes studied were 2-3 times lower than in microbial mats of lakes located in tropical zones. This can be explained by the relatively short warm period that lasts only 3-4 months per year. The highest measured rate of dark CO2 assimilation （59.8 mg C/（L·d）） was much lower than photosynthesis. The highest rate of sulfate reduction was 60 mg S/（L·d）, while that of methanogenesis was 75.6 μL CH4/（L·d） in the alkaline lakes of mongolian plateau. The rate of organic matter consumption during sulfate reduction was 3-4 orders of magnitude higher than that associated with methanogenesis.

关键词： alkaline lakes microbial mats mongolian plateau biogeochemical cycles

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Disease modifying treatment of spinal cord injury with directly reprogrammed neural precursor cells in non-human primates

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World Journal of Stem Cells 2021年第5期13卷 452-469页

作者： vladimir P Baklaushev Oleg V Durov vladimir A Kalsin Eugene V Gulaev Sergey V Kim Ilya L Gubskiy Veronika A Revkova Ekaterina m Samoilova Pavel A melnikov Dzhina D Karal-Ogly Sergey V Orlov Alexander V Troitskiy vladimir P Chekhonin Alexander V Averyanov Jan-Eric Ahlfors Biomedical Research Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Neurosurgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBAMoscow 115682MoskvaRussia Department of Anesthesiology N.N.Blokhin Russian Cancer Research CentreMoscow 115478MoskvaRussia Radiology and Clinical Physiology Scientific Research Center Federal center of brain research and neurotechnologies of the Federal Medical Biological AgencyMoscow 117997Russia Department of Neurobiology Serbsky National Medical Research Center for Psychiatry and NarcologyMoscow 119992MoskvaRussia Department of Primatology Russian Acad Med SciResearch Institute of Medical PrimatologySochi 119992SochiRussia Department of Vascular Surgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Basic and Applied Neurobiology V.P.Serbsky Federal Medical Research Center for Psychiatry and NarcologyRussia Department of medical Nanobiotechnology Pirogov Russian National Research Medical University(RNRMU)Moscow 115682MoskvaRussia New World Laboratories Laval H7V 4A7QuebecCanada

BACKGROUND The development of regenerative therapy for human spinal cord injury(SCI)is dramatically restricted by two main challenges:the need for a safe source of functionally active and reproducible neural stem cells and the need of adequate animal models for preclinical *** reprogramming of somatic cells into neuronal and glial precursors might be a promising solution to the first *** use of non-human primates for preclinical studies exploring new treatment paradigms in SCI results in data with more translational relevance to human *** To investigate the safety and efficacy of intraspinal transplantation of directly reprogrammed neural precursor cells(drNPCs).mETHODS Seven non-human primates with verified complete thoracic SCI were divided into two groups:drNPC group(n=4)was subjected to intraspinal transplantation of 5 million drNPCs rostral and caudal to the lesion site 2 wk post injury,and lesion control(n=3)was injected identically with the equivalent volume of *** Follow-up for 12 wk revealed that animals in the drNPC group demonstrated a significant recovery of the paralyzed hindlimb as well as recovery of somatosensory evoked potential and motor evoked potential of injured *** resonance diffusion tensor imaging data confirmed the intraspinal transplantation of drNPCs did not adversely affect the morphology of the central nervous system or cerebrospinal fluid *** immunohistochemical analysis showed that drNPCs maintained SOX2 expression characteristic of multipotency in the transplanted spinal cord for at least 12 wk,migrating to areas of axon growth *** Our data demonstrated that drNPC transplantation was safe and contributed to improvement of spinal cord function after acute SCI,based on neurological status assessment and neurophysiological recovery within 12 wk after *** functional improvement described was not associated with neuronal differentiation of th

关键词： Direct cell reprogramming Neural precursor cells Directly reprogrammed neural precursor cells Spinal cord injury Nonhuman primates Regenerative therapy,Evoked potentials

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A new kinetic model for the common juniper essenstial oil extraction by microwave hydrodistillation

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Chinese Journal of Chemical Engineering 2019年第3期27卷 605-612页

作者： miljana S. markovi? Svetomir ?. milojevi? Nevenka m. Bo?kovi?-Vragolovi? vladimir P. Pavi?evi? Ljiljana М. Babincev Vlada B. Veljkovi? Faculty of Technical Sciences University of Pri?tina Faculty of Technology and metallurgy University of Belgrade Faculty of Technology University of Ni?

The main objective of the present study was to model the kinetics of essential oil extraction from swelled ground juniper berries by classic hydrodistillation(HD) and microwave-assisted hydrodistillation(mAHD). A new phenomenological kinetic model was developed on the basis of the juniper essential oil extraction mechanism that assumed three mass transfer processes occurring simultaneously: washing, unhindered diffusion and hindered diffusion. The new model was compared to the existing kinetic models. Among the tested models,the new model had the smallest mean relative percentage deviation and the highest corrected Akaike information criterion value. In addition, that, the new model was verified for HD and mAHD of essential oils from some other plant materials. On the basis of the above-mentioned facts, the new model can be recommended for modeling the kinetics of essential oil extraction by both HD and mAHD.

关键词： Juniperus communis L Essential oil Kinetics microwave-assisted hydrodistillation modeling

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