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Transition from oceanic subduction to continental collision:insights from volcanogenic-sedimentary rocks of the Tannuola terrane(northern Central Asian orogenic Belt)

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Geoscience Frontiers 2024年第4期15卷 41-60页

作者： E.v.vetrov N.i.vetrova v.S.Sobolev institute of Geology and Mineralogy SB RAS Koptyuga ave.3NovosibirskRussia

Magmatism associated with oceanic subduction plays a dominant role in crustal growth during the Earth's *** Tannuola terrane,situated in the northern Central Asian orogenic Belt(CAoB),is a key area to understanding oceanic subduction and initial collision processes in the northern *** order to investigate the switch from subduction to collision settings,detailed field mapping,zircon SHRiMP U-Pb geochronological and whole-rock geochemical studies of volcanogenic-sedimentary rocks from the Tannuola terrane were carried *** U-Pb ages indicate multi-stage volcanism lasted at least 30 Ma from~540 to~510 Ma,that can be divided into three events:the late Ediacaran(before~540 Ma),the early Cambrian(~520 Ma)and the middle Cambrian(~510 Ma).These ages are inter-preted to the initial,main and final stages of oceanic subduction during the late Proterozoic-early *** the late Ediacaran,tholeiitic basalts with highεNd(t)values(from+7.4 to+8.5)were *** forming by the 10%-30%partial melting of spinel-garnet mantle source during slab *** the early Cambrian,transitional from tholeiitic to calc-alkaline basaltic rocks withεNd(t)value(+5.6)and coeval intermediate-felsic volcanic rocks with similarεNd(t)values(+5.9 and+6.5)*** early Cambrian basaltic rocks are interpreted to be derived by 10%-30%partial melt-ing of a depleted mantle source metasomatized by slab-derived fluids released from the subducting ocea-nic *** middle Cambrian calcalkaline basaltic rocks withεNd(t)value of+6.2 might be emplaced as a result of low(5%-10%)degree partial melting of a metasomatized mantle followed by fractional crys-tallization of cli.opyroxene and *** intermediate-felsic volcanic rocks withεNd(t)values from+6.0 to+6.8 were formed through fractionation of the juvenile Neoproterozoic *** middle Cambrian volcanism is interpreted to be triggered by the slab break-off during the transition to a collisional se

关键词： island-arc magmatism Ediacaran Cambrian zircon U-Pb dating Nd i.otopes Central asian orogenic belt

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.i.KUZMiNA Y.v.oSi.ov A.R.PESTEREv Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. in the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

Leading directions and effective distance of larch offspring dispersal at the upper treeline in the Northern and Polar Urals, Russia

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： P.A.Moiseev v.L.Semeri.ov T.v.Semeri.ova D.S.Balakin i.B.vorobiev S.o.viuykhin institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Genetics and Life Science Sirius University of Science and Technology354340SochiRussia

Climate has changed sufficiently over the last 150 years and forced out upper treeline advance at the most studied sites around the *** rate of advance has been extremely variable–from tens to hundreds meters in *** is because the degree at which tree frontal populations respond to climate change depends on the complex interaction of biological and physical *** resulting stand pattern is the consequence of the interaction between dispersal and survival functions.A few publications have addressed the question of how this pattern is *** order to understand how the spatial structure of tree stands was formed at the upper limit of their distribution in the Ural Mountains,we assessed the distance and direction of dispersal of offspring from maternal *** found that in frontal Larix sibirica ***,‘effective’dispersal of offspring ranges from 3 to 758 m(with a median of 20–33 m in open forest and 219 m in single-tree tundra in the Polar Urals and 107 m in open forest in the Northern Urals).We revealed that most of the offspring effectively dispersed not only in the direction of the prevailing winds,but also in the opposite direction up the slope,and the distance can reach 500–760 *** data obtained can be used to develop an individual-based model which is capable of simulating in detail the dynamics of tree stands at the upper limit of their growth and reliably predicting the future position and pattern of treeline ecotone as growth conditions continue to improve in the face of observed climate change.

关键词： Effective dispersal distance Upper treeline Parentage analysis Age estimation Terrestrial laser scanning Larix sibirica Ural mountains

Effect of Ta_(2)o_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vi.o behavior of PEo coatings on Mg-alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.v.Mashtalyar i.M.imshinetskiy v.v.Kashepa K.v.Nadaraia M.A.Piatkova A.i.Pleshkova K.A.Fomenko A.Yu.Usti.ov S.L.Sinebryukhov S.v.Gnedenkov institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vi.o,and biocompatibility of coatings containing Ta_(2)o_(5),which are obtained by plasma electrolytic oxidation(PEo)on MA8 magnesium *** obtained coatings demonstrate in vi.o biocompatibility and in vitro *** to the base PEo coating,the layers containing Ta_(2)o_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)o_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEo process contributing to sufficient soft tissue ingrowth in *** on in vi.o studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in compari.on with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEo coatings containing Ta_(2)o_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

Antibacterial HA-coatings on bioresorbable Mg alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1965-1985页

作者： K.v.Nadaraia D.v.Mashtalyar M.A.Piatkova A.i.Pleshkova i.M.imshinetskiy M.S.Gerasimenko E.A.Belov v.v.Kumei.o D.N.Kozyrev K.A.Fomenko v.v.Mostovaya B.R.Torpanov A.R.Biktimi.ov i.S.osmushko S.L.Sinebryukhov S.v.Gnedenkov institute of Chemistry FEB RAS 159 Pr.100-letiya VladivostokaVladivostok 690022Russia Far Eastern Federal University 10 Ajax BayRussky IslandVladivostok 690922Russia A.v.Zhirmunsky National Scientific Center of Marine Biology FEB RAS 17 St.PalchevskogoVladivostok 690041Russia Regional Clinical Dermatovenerological Dispensary 18 V St.GamarnikaVladivostok 690033Russia NMiC“Treatment and Rehabilitation Center” 3 Ivankovskoe highwayMoscow 125367Russia

in this study,a calcium-phosphate coating was formed on a Mg-Mn-Ce alloy by the plasma electrolytic oxidation(PEo).The antibiotic vancomycin,widely used in the treatment of infections caused by Staphylococcus aureus(***),was impregnated into the *** with vancomycin showed high bactericidal activity against *** mechanical and electrochemical properties of the formed coatings were studied,as well as in vitro cytotoxicity tests and in vi.o tests on mature male rats were *** to SEM,EDS,XRD and XPS data,coatings had a developed morphology and contained hydroxyapatite,which indicates high *** analysis of roughness of coatings without and with vancomycin did not reveal any differences,confirming the high roughness of the *** electrochemical tests,an increase in corrosion resistance by more than two times after the application of PEo coatings was *** to the results of an in vi.o study,after 28 days of the implantation of samples with calcium phosphate PEo coating and vancomycin,no signs of inflammation were observed,while an inflammatory reaction developed in the area of implantation of bare alloy,followed by *** release tests from the coatings show a sharp decrease in the concentration of the released antibiotic on day 7 and then a gradual decrease until day *** the experiment,no significant deviations in the condition and behavior of the animals were observed;clinical tests did not reveal a systemic toxic reaction.

关键词： Bioactive coatings Biocompatibility Mg alloy Plasma electrolytic oxidation Hydroxyapatite vancomycin

Development and testing of a high-power S-band klystron at BiNP SB RAS

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Nuclear Science and Techniques 2024年第7期35卷 58-67页

作者： A.Levichev A.Barnyakov S.Samoylov D.Niki.orov v.ivanov M.Arsentyeva D.Chekmenev o.Pavlov i.Pi.ovarov Budker institute of Nuclear Physics Lavrentyeva Av.11NovosibirskRussia630090 Novosibirsk State University Pirogova Str.2NovosibirskRussia630090

This paper details the development and testing of the first working prototype of the S-band high-power klystron,accomplished at the Budker institute of Nuclear Physics,Siberian Branch,Russian Academy of Sciences(BiNP SB RAS).Upon testing,the klystron demonstrated the following parameters:an operating frequency of 2856 MHz and a peak power output of 50 *** paper presents the klystron's design,its constituent units,and pertinent processing procedures,along with discussions on the measurement of its parameters.

关键词： Klystron Linear accelerator Electron beam

Highly Defective Dark Tio_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdi.ova o.A.Reutova T.A.Bugrova i.Yu.ovsyuk L.S.Kibis o.A.Stonkus D.B.vasilchenko o.v.vodyankina v.A.Svetlychnyi National Research Tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov institute of Catalysis NovosibirskRussia 630090 Ni.olaev institute of i.organic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed Co adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (oH) _(2) (No _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSi) eff ect of the transfer of electron density from the electron-saturated defects on the Tio _(2) surface to Pt ^(4+) . in the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSi eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/Tio_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)Tio_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

Photoluminescence,structural and antibacterial properties of co-dopedβ-Ca_(3)(Po_(4))_(2)-type phosphates Ca_(8)CuRE(Po_(4))_(7)(RE=Eu-Er)

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Journal of Rare Earths 2024年第9期42卷 1658-1668,I0002页

作者： ivan v.Niki.orov Ekaterina v.iliin Bogdan i.Lazoryak Sergey M.Aksenov Pavel v.Slukin Dina v.Deyneko Department of Chemistry Lomonosov Moscow State University119991MoscowRussia Laboratory of Arctic Mineralogy and Material Sciences Kola Science CentreRussian Academy of Sciences184209ApatityRussia Geological institute Kola Science CentreRussian Academy of Sciences184209ApatityRussia State Scientific Center of Applied Microbiology and Biotechnology of Rospotrebnadzor 24 Block A142279ObolenskRussia

Novel Ca_(8)CuRE(Po_(4))_(7)where RE^(3+)=Eu^(3+),Tb^(3+),Dy^(3+),Ho^(3+)and Er^(3+)were synthesized by a solid-state method in *** structures of the samples were characterized by powder X-ray diffraction using Rietveld refinement to determine the occupation of crystal *** samples are found to have a centrosymmetric structure with space group R3c,as shown by dielectric *** synthesized Ca_(8)CuRE(Po_(4))_(7)samples have multifunctional *** Cu^(2+)ions provide antibacterial properties,while the rare earth elements ions exhibit luminescence properties,and theβ-Ca_3(Po_(4))_(2)-type host is *** photoluminescence properties of RE^(3+)ions were studied and compared with other simmilar Ca_(8)MRE(Po_(4))_(7)phosphates,where M is a divalent *** photoluminescence intensity quenching in terms of energy transfer from RE^(3+)to Cu^(2+)is *** bioactive properties were studied in relation to antibacterial activity against *** and *** syntesized Ca_(8)CuRE(Po_(4))_(7)samples demonstrate very high and stable inhibition of bacteria *** correlation between crystal structure and properties is *** combining multiple approaches to the directio nal design of such materials,several important properties within a single chemical compound to achieve biovisualization and bioactive properties simultaneously can be combined.

关键词： β-Ca_(3)(Po_(4))_(2) Whitlockite-type structure Bioactive phosphates TCP Photoluminescence Rare earths

Selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： vladimir i.Kolpakov Sergey v.Fedorov Ekaterina P.vi.ogradova irina A.Bolotina Bauman Moscow State Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. it is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： Space debris Meteoric impact Explosion Shaped charge High-velocity aluminum element Segmental liner Combined liner Numerical simulation