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Interaction of edge dislocations with voids in tungsten

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Tungsten 2024年第3期6卷 633-646页

作者： Arseny Kazakov Rita I.Babicheva Aleksandr Zinovev Dmitry Terentyev Kun Zhou Elena A.Korznikova sergey v.Dmitriev Research Laboratory for Metals and Alloys under Extreme Impacts Ufa University of Science and TechnologyUfa 450008Russia Institute for Metals Superplasticity Problems of RAS Ufa 450001Russia School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore Institute for Nuclear Energy Technology Belgian Nuclear Research Center2400 MolBelgium Technological Machines and Equipment Department Ufa State Petroleum Technological UniversityUfa 450064Russia Institute of Mechanical Science Problems of RAS Saint Petersburg 199178Russia Institute of Molecule and Crystal Physics UFRC of Russian Academy of SciencesUfa 450075Russia

Tungsten is widely used as a material capable of withstanding extreme operating conditions and is one of the candidates for use in fusion and GenerationⅣfission *** modelling implemented to solve various material science problems is an indispensable approach for improving material *** work analyzes the interaction of an edge dislocation with a void in single-crystal tungsten with the help of molecular dynamics *** different approaches for studying the dynamics of dislocations in tungsten that differ in boundary conditions are *** interactions of the dislocation and void at different temperatures are investigated,and based on the obtained stress-strain curves,the dislocation obstacle strength for voids having various diameters is *** is shown that when applied to a crystal with small voids,the model with the fixed boundary conditions returns incorrect ***,the influence of the cell size for the model with periodic boundary conditions is analyzed,and the case of a non-central interaction of a dislocation with a void is *** obtained results improve our understanding of the mechanical response of irradiated materials.

关键词： Tungsten Molecular dynamics method Dislocations voids Boundary conditions

CaAl_(2)Si_(2)O_(8) polymorphs:Sensitive geothermometers and geospeedometers

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Geoscience Frontiers 2023年第1期14卷 33-45页

作者： Liudmila A.Gorelova Oleg S.vereshchagin vladimir N.Bocharov sergey v.Krivovichev Andrey A.Zolotarev Mikhail A.Rassomakhin Institute of Earth Sciences Saint Petersburg State UniversitySt.PetersburgRussia Centrefor Geo-Environmental Research and Modelling(Geomodel).Saint Petersburg State University St.PetersburgRussia Kola Science Centre ApatityMurmansk RegionRussia South Urals Federal Research Center of Mineralogy and Geoecology of UB RAS MiassRussia

Plagioclase is the major rock-forming mineral constituting the Earth's crust,whereas anorthite(CaAl_(2)Si_(2)O_(8))is a common minerals in lunar highlands crust,meteorites,possibly in some comets and on *** anorthite,two high-temperature polymorphs of CaAl_(2)Si_(2)O_(8)are known:dmisteinbergite and svyatoslavite,which are found in burnt coal dumps,meteorites and *** we present the results of detailed studies(quenching experiments,elemental analysis,Raman spectroscopy and in situ high temperature single crystal X-ray diffraction(up to 1000℃))on naturally co-occurring CaAl_(2)Si_(2)O_(8)polymorphs(anorthite,dmisteinbergite and svyatoslavite)from a burnt coal dump in Kopeisk,*** polymorphs were found in all natural samples and obtained upon heating of dmisteinbergite(unquenchableβ-dmisteinbergite and quenchable y-dmisteinbergite).It was shown that Ca coordination differs significantly in CaAl_(2)Si_(2)O_(8)polymorphs,resulting in a different capacity to host Ba and possibly other large ion lithophile *** our data on natural samples with the previously published data on natural and synthetic compounds,we propose a new scheme of CaAl_(2)Si_(2)O_(8)polymorphs *** results indicate that CaAl_(2)Si_(2)O_(8)polymorphs could be used for temperature estimations for both Earth and planetary sciences.

关键词： Feldspar Polymorphism Anorthite Dmisteinbergite Svyatoslavite CaAl_(2)Si_(2)O_(8)

High-pressure, High-temperature Synthesis and Properties of the Monoclinic Phase of Y2O3

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Chemical Research in Chinese Universities 2016年第4期32卷 545-548页

作者： ZHANG Qian WU Xiang OvSYANNIKOv v. sergey DONG Juncai QIN Shan DUBROvINSKY S. Leonid CHEN Dongliang Gemological Institute China University of Geosciences Wuhan 430074 P. R. China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 P R. China Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education & School of Earth and Space Sciences Peking University Beo'ing 100871 P. R. China Bayerisches Geoinstitut Universitat Bayreuth Bayreuth D-95447 Germany Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 P. R. China

The monoclinic phase of Y2O3（B-RES） has been synthesized using a Kawai-type multi-anvil apparatus under 20 GPa at 1800℃. Samples of the cubic Y2O3（C-RES） and monoclinic Y2O3 phases were characterized by synchrotron radiation X-ray diffraction, X-ray absorption near edge structure and Raman spectroscopy. Crystal structures of the cubic and monoclinic phases have been examined using Rietveld refinement of the X-ray diffraction data. The cubic-to-monoclinic transition of Y2O3 was reconstructive and irreversible. The X-ray diffraction results were further confirmed by simulation of the X-ray absorption spectra.

关键词： Y2O3 High pressure Multi-anvil synthesis

Struggle zone: alpine shrubs are limited in the Southern Urals by an advancing treeline and insufficient snow depth

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Journal of Forestry Research 2024年第6期35卷 1-12页

作者： Andrey A.Grigoriev vladimir S.Mikryukov Yulia v.Shalaumova Pavel A.Moiseev sergey O.vuykhin Jesús J.Camarero Institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesSt.8 Marta 202EkaterinburgRussia 6201442 Institute of Ecology and Earth Sciences University of TartuSt.Liivi 250409 TartuEstonia Pyrenean Ecology Institute St.Montañana 100550059 SaragossaSpain

In recent decades,the rapid climate warming in polar and alpine regions has been accompanied by an expan-sion of shrub ***,little is known about how changes in shrub distribution will change as the distribution of tree species and snow cover changes as temperatures *** this work,we analyzed the main environmental factors influencing the distribution and structure of Juniperus sibir-ica,the most common shrub species in the Southern Ural *** mapping and digital elevation models,we demonstrated that *** forms a well-defined vegeta-tion belt mainly between 1100 and 1400 m *** this zone,the abundance and cover of *** are influenced by factors such as rockiness,slope steepness,water regime and tree(Picea obovata)*** analysis of data spanning the past 9 years revealed an upward shift in the distribution of *** with a decrease in its *** primary limit-ing factors for the distribution of *** were the removal of snow cover by strong winter winds and competition with *** a consequence of climatic changes,the tree line and forest limit have shifted upward,further restricting the distribution of *** to higher elevations where com-petition for light with trees is reduced and snow cover is sufficiently deep.

关键词： Juniperaceae Juniperus sibirica Snowpack cover Shrubline Shrub-tree competition Southern Urals Tree line

Self-Assembly and Ordering of C60 on the WO2/W（110） Surface

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Nano Research 2011年第2期4卷 194-203页

作者： sergey A. Krasnikov sergey I. Bozhko Kevin Radican Olaf Lübben Barry E. Murphy Sundar-Raja vadapoo Han-Chun Wu Mohamed Abid valery N. Semenov lgor v. Shvets Centre tbr Research on Adaptive Nanostrucmres and Nanodevices （CRANN） School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Russian Federation King Abdullah Institute for Nanoteclmology College of Science King Saud University Riyadh 1145l Saudi Arabia

The growth and ordering of C60 molecules on the WO2/W（110） surface have been studied by low-temperature scanning tunnelling microscopy and spectroscopy （STM and STS）, low-energy electron diffraction （LEED）, and density functional theory （DFT） calculations. The results indicate the growth of a well-ordered C60 layer on the WO2/W（110） surface in which the molecules form a close-packed hexagonal structure with a unit cell parameter equal to 0.95 nm. The nucleation of the C60 layer starts at the substrate＇s inner step edges. Low-temperature STM of C60 molecules performed at 78 K demonstrates well-resolved molecular orbitals within individual molecules. In the C60 monolayer on the WO2/W（110） surface, the molecules are aligned in one direction due to intermolecular interaction, as shown by the ordered molecular orbitals of individual C60. STS data obtained from the C60 monolayer on the WO2/W（110） surface are in good agreement with DFT calculations.

关键词： Fullerenes self-assembly tungsten oxide low-temperature scanning tunnelling microscopy scanning tunnellingspectroscopy W(110)

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

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Journal of Environmental Sciences 2020年第2期32卷 177-186页

作者： Irina S.Ryzhkina Yuliya v.Kiseleva Lyaisan I.Murtazina Tatyana v.Kuznetsova Erik R.Zainulgabidinov Igor v.Knyazev Andrew M.Petrov sergey E.Kondakov Alexander I.Konovalov Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific CenterRussian Academy of Sciences8 Arbuzov str.Kazan 420088Russia Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences 28 Daurskaya Str.Kazan 420087Russia Lomonosov Moscow State University Chemistry Dept.1/3 Lenin HillsMoscow 119899Russia

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater *** consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to *** provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these *** the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of *** physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/*** relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and *** was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

关键词： Diclofenac sodium Low concentration Aqueous solutions Physicochemical properties Hydrobionts Toxicity

Russia’s Peace Initiatives in the MENA Region: Evaluation and Prospects

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Asian Journal of Middle Eastern and Islamic Studies 2019年第4期13卷 534-555,I0004页

作者： sergey v.Kostelyanets Institute for African Studies Russian Academy of SciencesMoscowRussia Department of African and Arab Studies Peoples’Friendship University of RussiaMoscowRussia

Russia’s recent thundering‘return’to the Middle East is first and foremost an obvious result of the effective use of hard power,rather than the tools of soft power such as economics or diplomacy,which played important but secondary *** most visible symbol of this return is the establishment of two permanent sovereign Russian military bases in ***,Moscow has extensive experience in employing hard power to protect its interests,but political,financial and security costs and risks of its application are aplenty,which will dictate Russia’s more cautious policy on this matter in the *** gained a military foothold in the region,Russia now seeks to augment its influence in the MENA region further,and increasingly through the use of soft power,particularly diplomatic *** Astana-Sochi process is the format that Russia has moulded for this *** study seeks to provide,first,an analysis of the Astana-Sochi process for Syria,its theoretical foundations and practical implementations,evaluation of its strengths and weaknesses,and then explore its applicability in the MENA region considering both objective features of the format and more subjective implications of the wider Russian involvement in the region against the backdrop of rising tensions between Moscow and the West.

关键词： Russia peace initiatives the Gulf the Middle East and North Africa conflict resolution

Recent Russian remote sensing investigations in Antarctica within the framework of scientific traverses

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Advances in Polar Science 2015年第2期26卷 113-121页

作者： sergey v.Popov Polar Marine Geosurvey Expedition (PMGE) 24 Pobeda Str.St.-PetersburgLomonosov198412Russia

This paper includes a short historical review of Russian and Soviet scientific traverses to study the Antarctic inland. The first traverse left on April 2, 1956. It resulted in the opening of the first Russian inland research station named Pionerskaya and provided the first geophysical and glaciological data on regions inland of the Antarctic coast. By 1965, a number of regional inland scientific traverses had been completed and. the first Atlas of Antarctica was published in 1966. The atlas presented the main achievements of that time. After the discovery of Lake vostok, Russian scientists commenced remote sensing investigations to study this unique natural phenomenon. The propagation of acoustic and electromagnetic waves in the glacier near vostok Station were measured to provide important geophysical data. Radio-echo sounding data showed that Lake vostok is isolated and separated from the rest of the Antarctic subglacial hydrosphere. The total area of the lake is 15 790 km2, excluding 365 km^2 occupied by 11 islands. Reflection seismic soundings of Lake vostok estimated a total volume of about 6 100 km^3, an average depth of about 400 m, and a maximum depth of 1 200 m. Since 2008, there have been a number of scientific traverses between Mirny and vostok stations and between Progress and vostok stations. The data collected during the traverses have provided new insights into sub-ice topography and ice sheet structure, and have led to the discovery of subglacial lakes near Komsomolskaya Station and under Pionerskaya Station.

关键词： Russian scientific traverses Lake vostok Antarctica remote sensing radio-echo sounding seismic

Symmetry of echinoderms: From initial bilaterally-asymmetric metamerism to pentaradiality

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Natural Science 2014年第4期6卷 171-183页

作者： sergey v. Rozhnov Borissiak Paleontological Institute RAS Moscow Russia

Echinoderm radial symmetry has first appeared in the ambulacral system, when the ambulacral channel assumed the shape of a closed ring or a horseshoe with approximated ends, and then spread onto other organ systems. Its origin was a natural consequence of a steady increase of the original asymmetry of bilaterally-asymmetric three-segmented ancestors of echinoderms, culminated by closing of the ancestral linear metamerism into radiality. The evolutionary transformation from a simple pouchlike hydrocoel with one side channel to an elongated hydrocoel (located under the oesophagus) with two side channels, and finally to a nearly closed horseshoeshaped hydrocoel with three radial channels can be reconstructed based on the theca structure and the number of ambulacra in the row SolutaCincta-Helicoplacoidea. After the hydrocoel with three outbound ambulacral channels circled around the oesophagus as a horseshoe, it either closed into a ring, or its ends became closely approximated. This has determined the primary triradiate symmetry, which quickly transformed into pentaradial symmetry of the 2-1-2 type as a result of branching of two of the three primary radial channels. This occurred no earlier than the Late vendian, when the first bilaterians appeared to have begun to acquire body appendages, and no later than the Early Cambrian, when the first skeletal remains of echinoderms entered the fossil record (in the Atdabanian). The 2-1-2 pentaradial symmetry evolved into the true pentaradiality as a result of shifting the timing of tentacle branching to earlier stages of ontogenesis and even spreading of the five tentacle primordia over the ambulacral ring. This occurred during the Ordovician.

关键词： Echinodermata Symmetry Asymmetry Metamerism Pentaradiality Body Plan Hox Genes Colinearity