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The state of gold in phases of the Cu-Fe-S system:In situ X-ray absorption spectroscopy study

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Geoscience Frontiers 2023年第3期14卷 103-116页

作者： Boris R.Tagirov Olga N.Filimonova Alexander l.trigub Ilya V.Vikentyev Elena V.Kovalchuk Maximilian S.Nickolsky Andrey A.Shiryaev Vladimir l.Reukov Dmitry A.Chareev Institute of Geology of Ore Deposits(IGEM RAS) 35Staromonetnyi per119017 MoscowRussia National Research Centre‘Kurchatov Institute’ 1Akademika Kurchatova pl123182 MoscowRussia Institute of Physical Chemistry and Electrochemistry(IPCE RAS) 31Leninsky Prospect119071 MoscowRussia Institute of Experimental Mineralogy(IEM RAS) 142432 ChernogolovkaMoscow RegionRussia

Chalcopyrite and bornite are the main Au-bearing minerals at Cu porphyry deposits,volcanogenic massive sulfide(VMS)deposits,Cu-Ni deposits of the mafic magmatic complexes,and ores of submarine sulfide *** and intermediate solid solutions with wide compositional variations(bnss and iss–high-temperature chalcopyrite,correspondingly),which can scavenge economic concentrations of Au,appear in the Cu-Fe-S system at ore-forming ***,the state of Au in bnss and iss is yet *** solve this conundrum,we synthesized samples with net chemical composition of bnss and iss,studied them by in situ X–ray absorption spectroscopy(XAS),and used the experimental data to explain the Au distribution among natural ore-forming *** sulfide samples were obtained at 495–700℃ in Au-saturated system by means of salt flux *** bnss contained1.2–1.6 log units more Au than iss:up to 18 wt.%Au in bnss vs 0.4 wt.%Au in iss at 700*** increase of temperature resulted in the sharp increase of Au concentration in both phases,1 log unit per 100℃ at f(S2)close to S_((l)) *** of Au l_(3)-edge spectra recorded at 25–675℃ revealed that at 25℃ Au exists mainly in the metallic *** t>500℃ the spectral features of Audisappear,and “chemically bound”Au *** Au form of occurrence in the iss field is interpreted as Au-bearing clusters with a stromeyerite-like(CuAgS)*** Cu_(2–x)S and bnss contain Au in a mixture of stromeyeritelike and petrovskaite-like(Au_(0.8)Ag_(1.2)S)*** chemical composition of both forms is close to CuAuS,where the nearest Au neighbors are two S atoms at R_(Au-S)=2.34–2.36Å.Results of the present study allow to determine the state of Au and its concentration in the main Cu-bearing minerals of sulfide ores as a function of the T-f(S_(2))-compositional *** to the sharp increase of the CuAuS clusters stability with increasing temperature,in high-temperature ores formed at t>350℃ A

关键词： “Invisible”gold Bornite solid solution Intermediate solid solution Digenite Chalcopyrite X-ray absorption spectroscopy

Thermal transport in semiconductor nanostructures, graphene,and related two-dimensional materials

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Chinese Physics B 2018年第5期27卷 74-82页

作者： alexandr I.Cocemasov Calina I.Isacova Denis l.Nika E.Pokatilov laboratory of Physics and Engineering of Nanomaterials Department of Physics and EngineeringMoldova State University

We review experimental and theoretical results on thermal transport in semiconductor nanostructures（multilayer thin films, core/shell and segmented nanowires）, single-and few-layer graphene, hexagonal boron nitride, molybdenum disulfide, and black phosphorus. Different possibilities of phonon engineering for optimization of electrical and heat conductions are discussed. The role of the phonon energy spectra modification on the thermal conductivity in semiconductor nanostructures is revealed. The dependence of thermal conductivity in graphene and related two-dimensional（2 D） materials on temperature, flake size, defect concentration, edge roughness, and strain is analyzed.

关键词： phonons thermal conductivity nanowire graphene two-dimensional (2D) materials

Impact of air drought on photosynthesis efficiency of the Siberian crabapple(Malus baccata l. Borkh.) in the forest-steppe zone of Transbaikalia, Russia

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Journal of Arid land 2019年第2期11卷 255-266页

作者： alexandr RUDIKOVSKII Elena RUDIKOVSKAYA lyubov DUDAREVA Siberian Institute of Plant Physiology and Biochemistry of Siberian Branch Russian Academy of Sciences

The adaption of photosynthesis, being a key metabolic process, plays an important role in plant resistance to air drought. In this study, the Siberian crabapple(Malus baccata l. Borkh.) in the forest-steppe zone of Transbaikalia region, Russia, was subjected to air drought stress and its photosynthesis characteristics were analyzed. The results show that air drought and sufficient soil moisture supply lead to the decrease in the total chlorophyll(Chl) content, while the ratio of Chls to carotenoids is constant in the Siberian crabapple tree. The function of photosystem II(PS-II) in the crabapple trees is characterized by a decrease in the fraction of absorbed light energy spent on the photochemical work and an increase in the proportion of non-photosynthetic thermal quenching. These changes indicate the photosynthetic down-regulation that acts as a universal photoprotective mechanism. During the midday hours, the combination of high air temperature and low air humidity leads to the decrease in the maximum photochemical quantum yield of photosystem II(Fv/Fm) and the efficiency of photosynthesis(PABS). The parameters of leaf gas exchange show the significant differences in these values between the control and experimental variants. During the morning hours, the Siberian crabapple, growing in the Irkutsk City,assimilates carbon dioxide more intensively. Due to the higher air humidity, the stomata are kept open and the necessary amount of carbon dioxide entries the sites of carboxylation. The low air humidity combined with wind in the experimental variants leads to the unreasonably high water loss in the crabapple leaves by more than 27% as compared to the control variant(Irkutsk City). However, water use efficiency in the morning hours increases during plant photosynthetic processes, i.e., 42% higher than that of control. This,apparently, is a reflection of the adaptation processes of the Siberian crabapple to the air drought and parching wind.

关键词： air drought chlorophyll fluorescence leaf gas exchange pigments water use efficiency

Effects of long-term medieval agriculture on soil properties:A case study from the Kislovodsk basin,Northern Caucasus,Russia

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Journal of Mountain Science 2018年第6期15卷 1171-1185页

作者： CHERNYSHEVA Elena KHOMUTOVA Tatiana FORNASIER Flavio KUZNETSOVA Tatiana BORISOV alexandr Institute of Physicochemical and Biological Problems in Soil Science Russian Academy of Sciences Institutskaya 14229o Pushchino Moscow region Russia 2 CREA - VE Consiglio per la ricerca in Agricoltura e rAnalisi della Economia Agraria Centro di Ricerea Viticoltura ed Enologia Via Trieste 23 34170 Gorizia Italy

The chemical properties and biological activities of soils were studied in the vicinity of the medieval settlement Podkumskoe-3 in the Kislovodsk basin(Northern Caucasus, Russia). Between the 5 th and 8 th centuries this area was ploughed regularly, but it was then abandoned up to the present day. It has been established that past human activity leads to soil undergoing significant transformations in terms of microbial communities and enzyme activity, and that such changes are maintained over long periods. long-term manuring in the middle of the first millennium AD led to an increase in organic carbon content and the accumulation of nitrate nitrogen. Soils of ancient abandoned fields are associated with increases in microbial biomass, number of saprotrophic bacteria, urease activity, and fungal mycelium biomass. The observed changes in the microbiological and biochemical properties of soil were conditioned by secondary anthropogenically induced succession after the abandonment of arable lands.

关键词： Anthropogenic soils Manuring Enzymeactivity Microbial biomass North Caucasus MiddleAges

Practical obstacles and their mitigation strategies in compressional optical coherence elastography of biological tissues

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Journal of Innovative Optical Health Sciences 2017年第6期10卷 51-63页

作者： Vladimir Y.Zaitsev alexandr l.Matveyev lev A.Matveev Ekaterina V.Gubarkova alexandr A.Sovetsky Marina A.Sirotkina Grigory V.Gelikonov Elena V.Zagaynova Natalia D.Gladkova Alex Vitkin Institute of Applied Physics Russian Academy of Sciences Ulyanova Street 46 Nizhny Novgorod 603950 Russia Nizhny Novgorod State Medical Academy 10/1 Minina Square Nizhny Novgorod 603005 Russia University of Toronto and University Health Network 610 University Avenue Toronto ON M5G 2M9Canada

In this paper,we point out some practical obstacles arising in realization of compressional optical coherence elastography(OCE)that have not attracted sufficient attention ***-cally,we discuss(i)complications in quantification of the Young modulus of tissues related to partial adhesion between the OCE probe and soft intervening reference layer sensor,(i)distorting influence of tisue suface curvature/corrugation on the subsurface strain distri-bution mapping,(ii)ways of signal-to-noise mtio(SNR)enhancement in OCE strain mapping when periodic averaging is not realized,and(iv)potentially significant infuence of tissue elastic nonlinearity on quantification of its *** pnactical approaches to mitigate the effects of these complications are also described.

关键词： Optical coherence elastography optical coherence tomography phase-resolved methods strain mapping stiffness characterization

Circle of life:the common hamster(Cricetus cricetus)adaptations to the urban environment

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Integrative Zoology 2019年第4期14卷 383-395页

作者： Alexey V.SUROV Elena A.ZAYTSEVA alexandr V.KUPTSOV Elena A.KATZMAN Pavel l.BOGOMOlOV alexandra S.SAYAN Ekaterina V.POTASHNIKOVA Nikolay N.TOVPINETZ Ekaterina V.KUZNETSOVA Alexey Y.TSEllARIUS Natalia Y.FEOKTISTOVA Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Centre of Hygiene and Epidemiology in Crimea and in the Municipal City Sevastopol SimferopolRussia

Traditionally,urbanization has been seen as a negative phenomenon for ***,changes in the environmental parameters induced by urbanization might be favorable for some *** the past half-century,the common hamster has actively populated cities,establishing populations in some European,Russian and Kazakhstan *** on integrative methods,we investigated free-range common hamsters inhabiting Simferopol from 2015 to 2018 to reveal possible adaptations to the urbanized environment across several parameters,including lifespan,hibernation period,reproductive activity and body *** show that in urban areas,the common hamster demonstrates an extremely short hibernation period compared to other localities,possibly due to enhanced food resources from urban forestry(walnuts,locus and hazelnut),allowing the species to start breeding very early(February)and finish as late as *** present the first evidence of polyandry for this species:mating of receptive females with several males and subsequent confirmation of multiple *** high reproductive potential,the lifespan of the common hamster in urban conditions is generally very short(less than 1 year).We speculate that in the process of synurbization,the common hamster’s innate plasticity across many life history traits permits it to successfully colonize throughout a wide range of habitats,with the ability to form novel adaptations to urban environments.

关键词： body mass hibernation lifespan multiple paternity synurbization

Mechanism and kinetics of iron extraction from high silica boehmite−kaolinite bauxite by hydrochloric acid leaching

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Transactions of Nonferrous Metals Society of China 2021年第10期31卷 3128-3149页

作者： Dmitry VAlEEV Denis PANKRATOV Andrei SHOPPERT Artem SOKOlOV alexandr KASIKOV alexandra MIKHAIlOVA Cristian SAlAZAR-CONCHA Ilia RODIONOV laboratory of Sorption Methods Vernadsky Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences119334 MoscowRussia Department of Chemistry Lomonosov Moscow State University119991 MoscowRussia Department of Non-ferrous Metals Metallurgy Ural Federal University620002 YekaterinburgRussia Tananaev Institute of Chemistry Kola Science Centre of the Russian Academy of Sciences184209 ApatityRussia laboratory of Crystal Structure Studies A.A.Baikov Institute of Metallurgy and Materials ScienceRussian Academy of Sciences119334 MoscowRussia Universidad Austral de Chile ValdiviaChile Graphite Innovation and Technologies Dartmouth NSCanada

The chemical and mineral compositions of bauxite recovered from the Severoonezhsk Bauxite Mine(Arkhangelsk region,Russia)were studied by XRD,ICP-OES,TG/DSC,SEM,TEM,and Mössbauer *** iron-containing minerals of the bauxites were found to comprise alumogoethite(α-Fe_(1−x)Al_(x)OOH),alumohematite(α-(Fe_(1−x)Al_(x))_(2)O_(3)),alumoakaganeite(β-Fe_(1−x)Al_(x)O(OH,Cl)),and chromite(FeCr_(2)O_(4)).The efficiency of Fe extraction from the bauxite by HCl leaching was 82.5%at 100℃,HCl concentration of 10%,solid/liquid ratio of 1:10,and the process duration of 60 min,with aluminum loss from the bauxites below 4.5%of the total Al contents in the *** of the kinetics of the iron leaching process proved diffusion to be the limiting stage of the process at 90−100℃.Bauxite residue after leaching presented traces of α-Fe_(1−x)Al_(x)OOH and β-Fe_(1−x)Al_(x)O(OH,Cl),and most of the iron content was in the FeCr_(2)O_(4).In bauxite residue after HCl leaching,in addition to iron oxide,the contents of chromium and calcium oxides significantly *** iron chloride liquor after leaching contained the rare earth elements(REE)of 6.8 mg/l Sc,4.1 mg/l Ce and 2.3 mg/l Ga.

关键词： bauxite acid leaching iron extraction kinetics Mössbauer spectroscopy

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Efficacy of the new therapeutic approach in curing malignant neoplasms on the model of human glioblastoma

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Cancer Biology & Medicine 2021年第3期18卷 910-930页

作者： Evgeniya V.Dolgova Oleg M.Andrushkevich Polina E.Kisaretova Anastasia S.Proskurina Genrikh S.Ritter Tatyana D.Dubatolova Margarita V.Romanenko Oleg S.Taranov Yaroslav R.Efremov Evgeniy l.Zavyalov alexandr V.Romaschenko Sergey V.Mishinov Svetlana S.Kirikovich Evgeniy V.levites Ekaterina A.Potter alexandr A.Ostanin Elena R.Chernykh Stanislav Yu.Roshchin Anatoliy V.Bervitskiy Galina I.Moysak Jamil A.Rzaev Sergey S.Bogachev Institute of Cytology and Genetics SB RAS Novosibirsk 630090Russia A.I.Evdokimov Moscow State University of Medicine and Dentistry Moscow 127473Russia Institute of Molecular and Cellular Biology Novosibirsk 630090Russia Novosibirsk State University Novosibirsk 630090Russia The State Research Center of Virology and Biotechnology"Vector" KoltsovoNovosibirsk 630559Russia First Department of Neurosurgery Ya.L.Tsivian Novosibirsk Research Institute of Traumatology and OrthopaedicsNovosibirsk 630091Russia Institute of Fundamental and Clinical immunology Novosibirsk 630099Russia Sklifosovsky Research Institute of Emergency Medicine Moscow 129010Russia Federal Center of Neurosurgery Novosibirsk 630048Russia

Objective:Glioma is a highly invasive tumor,frequently disposed in essential areas of the brain,which makes its surgical excision extremely difficult;meanwhile adjuvant therapy remains quite ***:In the current report,a new therapeutic approach in curing malignant neoplasms has been performed on the U87 human glioblastoma *** approach,termed"Karanahan",is aimed at the eradication of cancer stem cells(CSCs),which were recently shown to be capable of internalizing fragments of extracellular double-stranded *** being internalized,these fragments interfere in the process of repairing interstrand cross-links caused by exposure to appropriate cytostatics,and such an interference results either in elimination of CSCs or in the loss of their tumorigenic *** of the approach requires a scheduled administration of cytostatic and complex composite double-stranded DNA ***:U87 cells treated in vitro in accordance with the Karanahan approach completely lost their tumorigenicity and produced no grafts upon intracerebral transplantation into immunodeficient *** SCID mice with developed subcutaneous grafts,the treatment resulted in reliable slowing down of tumor growth rate(Pl transplantation of U87 cells followed by surgical excision of the developed graft and subsequent therapeutic treatment,the Karanahan approach was shown to reliably slow down the tumor growth rate and increase the median survival of the mice twofold relative to the ***:The effectiveness of the Karanahan approach has been demonstrated both in vitro and in vivo in treating developed subcutaneous grafts as well as orthotopic grafts after surgical excision of the tumor.

关键词： Glioblastoma U87 cell line mytomycin C cancer stem cells TAMRA

Social structure and space use of Amur tigers(Panthera tigris altaica)in Southern Russian Far East based on GPS telemetry data

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Integrative Zoology 2015年第4期10卷 365-375页

作者： Jose A.HERNANDEZ-BlANCO Sergei V.NAIDENKO Maria D.CHISTOPOlOVA Victor S.lUKAREVSKIY Alexey KOSTYRYA alexandr RYBIN Pavel A.SOROKIN Mikhail N.lITVINOV Andrey K.KOTlYAR Dale G.MIQUEllE Viatcheslav V.ROZHNOV A.N.Severtsov Institute of Ecology and Evolution Russian Academy of ScienceMoscowRussia V.l.Komarov Ussuriskii State Nature Reserve Far Eastern BranchRussian Academy of ScienceUssuriskRussia Institute of Biology and Soil Sciences Far Eastern BranchRussian Academy of ScienceVladivostokRussia Wildlife Conservation Society VladivostokRussia

To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the land of the leopard National Park in southwest Primorye,Russian Far *** kernel estimates of male home ranges were larger than those of female home ranges(Pl♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further *** overlap of adjacent home ranges suggested that females retained exclusive *** core areas of females overlapped only slightly,and remained stable over multiple *** home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of ***,real core areas of males did not overlap,suggesting some spatial *** comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards *** believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for *** monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.

关键词： Amur tiger GPS-Argos telemetry home range overlap Panthera tigris altaica space use social structure sex ratio