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Formation of Nanoscale intermetallic Phases in Ni Surface Layer at High intensity implantation of Al ions

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Journal of Materials Science & Technology 2004年第5期20卷 583-586页

作者： i.A.Bozhko S.v.Fortuna i.A.Kurzina i.B.Stepanov E.v.Kozlov Yu.P.Sharkeev Tomsk State University of Architecture & Building 2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaNuclear Physics InstituteTomsk Polytechnic University2a Lenin Str.Tomsk 634050RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003.RussiaInstitute of Strength Physics and Materials ScienceRussian Academy of Sciences2/1 Pr.AkademicheskiiTomsk 634021Russia

The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source 'Raduga-5'. it was shown that at the high intensity ion implantation the fine dispersed particles of Ni3Ai, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-Ai phase diagram.

关键词： High intensive ion implantation ion-plasma source intermetallic nanophases

High-Strength Nanostructured Cold-Resistant Steels for Continental Shelf Development

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Journal of iron and Steel Research international 2011年第S1期18卷 66-71页

作者： Oryshchenko A S Khlusova E i Orlov v v FSUE CRiSM PROMETEY St.PetersburgRussia

The article describes principles of developing steels for maritime structures and main *** scientific approach lies in forming an ultra fine-grained and submicrocrystal structure through thermomechanical treatment of low-carbon low-alloyed steels,providing higher strength and resistance to brittle *** article presents results of assessing the operability characteristics and introducing new steels.

关键词： low-alloyed steels microstructure mechanical properties thermomechanical treatment

Microstructure and mechanical properties of new Mg-Zn-Y-Zr alloys with high castability and ignition resistance

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international Journal of Minerals,Metallurgy and Materials 2024年第12期31卷 2714-2726页

作者： T.A.Koltygina v.E.Bazhenov A.v.Koltygin A.S.Prosviryakov N.Y.Tabachkova i.i.Baranov A.A.Komissarov A.i.Bazlov National University of Science and Technology MiSiS Moscow 119049Russia A.M.Prokhorov General Physics institute Russian Academy of SciencesMoscow 119991Russia Moscow State University of Medicine and Dentistry Moscow 127473Russia

Complex studies of new Mg-Zn-Y-Zr system alloys have been carried *** content range for the formation of the two-phase structure MgSS(Mg solid solution)+LPSO(long-period stacking ordered)in alloys of the Mg-Zn-Y-Zr system was determined by thermodynamic *** effect of heat treatment regimes on microstructure,mechanical,and corrosion properties was *** fluidity,hot tearing tendency,and ignition temperature of the alloys were *** best combination of castability,mechanical,and corrosion properties was found for the Mg-2.4Zn-4Y-0.8Zr *** alloys studied are superior to their industrial counterparts in terms of technological properties,while maintain high corrosion and mechanical *** increased level of pro-perties is achieved by a suitable heat treatment regime that provides a complete transformation of the 18R to 14H modification of the LPSO phase.

关键词： metals and alloys liquid-solid reactions microstructure fluidity mechanical properties corrosion transmission electron mi-croscopy

Canine distemper virus as a threat to wild tigers in Russia and across their range

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integrative Zoology 2015年第4期10卷 329-343页

作者： Martin GiLBERT Svetlana v.SOUTYRiNA ivan v.SERYODKiN Nadezhda SULiKHAN Olga v.UPHYRKiNA mikhail GONCHARUK Louise MATTHEWS Sarah CLEAvELAND Dale G.MiQUELLE Wildlife Conservation Society BronxNew YorkUSA Boyd Orr Centre for Population and Ecosystem Health Institute of BiodiversityAnimal Health and Comparative MedicineCollege of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowUK Pacific Geographical institute Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Far Eastern Federal University VladivostokRussia institute of Biology and Soil Sciences Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Lazovskii State Nature Zapovednik LazoPrimorskii KraiRussia

Canine distemper virus(CDv)has recently been identified in populations of wild tigers in Russia and *** populations are generally too small to maintain CDv for long periods,but are at risk of infections arising from more abundant susceptible hosts that constitute a reservoir of *** CDv is an additive mortality factor,it could represent a significant threat to small,isolated tiger *** Russia,CDv was associated with the deaths of tigers in 2004 and 2010,and was coincident with a localized decline of tigers in Sikhote-Alin Biosphere Zapovednik(from 25 tigers in 2008 to 9 in 2012).Habitat continuity with surrounding areas likely played an important role in promoting an ongoing *** recommend steps be taken to assess the presence and the impact of CDv in all tiger range states,but should not detract focus away from the primary threats to tigers,which include habitat loss and fragmentation,poaching and retaliatory *** priorities include:(i)recognition and diagnosis of clinical cases of CDv in tigers when they occur;and(ii)collection of baseline data on the health of wild *** infection of individual tigers need not imply a conservation threat,and modeling should complement disease surveillance and targeted research to assess the potential impact to tiger populations across the range of ecosystems,population densities and climate extremes occupied by *** the role of domestic and wild carnivores as contributors to a local CDv reservoir is an important precursor to considering control measures.

关键词： canine distemper virus conservation threat extinction Panthera tigris altaica population decline

v2551 Cyg:a pulsating star with enigmatic peculiarities

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Research in Astronomy and Astrophysics 2017年第7期17卷 57-66页

作者： Diana P.Kjurkchieva velimir A.Popov Dragomir v.Marchev Kenneth T.Menzies Nikola i.Petrov Department of Physics Shumen University iRiDA Observatory Rozhen NAO Tigh Speuran Observatory institute of Astronomy and NAO Bulgarian Academy of Sciences

intensive photometric and spectral observations of the variable star v2551 Cyg are *** light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing binary. The period and amplitude of the light curve, the amplitudes of color changes and the radial velocity curve of v2551 Cyg are similar to those of a high-amplitude δ Scuti variable. The target seems to pulsate with the fundamental mode. However, v2551 Cyg exhibits several important peculiarities：（i） the decreasing branch of its light curve is steeper than the increasing one;（ii） the radial velocity curve has a flat section in the phase range 0.7-1.2 and short increase of the negative radial velocity at phase 0.7;（iii） the rotational velocity is quite big for a HADS star;（iv） the Fourier coefficients of v2551 Cyg are quite different from those of HADS stars. The target classification is difficult due to these peculiarities.

关键词： stars variables delta Scuti - stars variables RR Lyrae - stars individual (v2551 Cyg)

Petrology,geochemistry and source characteristics of the Burpala alkaline massif,North Baikal

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Geoscience Frontiers 2017年第4期8卷 711-719页

作者： N.v.vladykin i.A.Sotnikova vinogradov institute of Geochemistry Siberian BranchRussian Academy of Sciences

The Burpala alkaline massif contains rocks with more than 50 minerals rich in Zr,Nb,Ti,Th,Be and rare earth elements（REE）.The rocks vary in composition from shonkinite,melanocratic syenite,nepheline and alkali syenites to alaskite and alkali granite and contain up to 10%LiLE and HSFE,3.6%of REE and varying amounts of other trace elements（4%Zr,0.5%Y,0.5%Nb,0.5%Th and 0.1%U）.Geological and geochemical data suggest that all the rocks in the Burpala massif were derived from alkaline magma enriched in rare earth *** extreme products of magma fractionation are REE rich pegmatites,apatite-fiuorite bearing rocks and *** Sr and Nd isotope data suggest that the source of primary melt is enriched mantle（EM-Ⅱ）.We correlate the massif to mantle plume impact on the active margin of the Siberian continent.

关键词： Syenite Pegmatite Rare metal and rare earths Petrology Geochemistry

Synthesis,structure and magnetic properties of Sm_(1.2)Ho_(0.8)Fe_(17)Hx(X=0;4.4)

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Journal of Rare Earths 2021年第9期39卷 1089-1094页

作者： S.v.veselova M.A.Paukov i.S.Tereshina v.N.verbetsky K.v.Zakharov D.i.Gorbunov A.N.vasiPev Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Nuclear Fuel Cycle Department.Centrum vyzkumu Rez Hlavni 130Husinec-Rez 25068.Czech Republic immanuel Kant Baltic Federal University Kaliningrad 236004Russia Faculty of Mathematics and Physics Charles UniversityPrague 12116Czech Republic Hochfeld-Magnetlabor Dresden(HLD-EMFL) Helmholtz-Zentrum Dresden-RossendorfDresden 07328Germany f National Research South Ural State UniversityChelyabinsk 454080Russia

intermetallic compounds based on rare-earth metals and iron are by far the most promising materials for permanent mag *** this work,the multicomponent compound Sm_(1.2)Ho_(0.8)Fe_(17)was prepared by in duction *** hydride Sm_(1.2)Ho_(0.8)Fe_(17)H_(4.4)with a high hydrogen content was obtained by direct hydrogenation of the intermetallic *** rhombohedral Th2Zn17-type of structure(space group R3^(-)m)is inhere nt to parent compound and hydride as *** effect of hydrogenation on the magneric properties of Sm_(1.2)Ho_(0.8)Fe_(17)was *** temperature of the hydride Sm_(1.2)Ho_(0.8)-Fe_(17)H_(4.4)is higher than that of parent compound by△Tc=138 *** hydrogen embedded in Sm_(1.2)Ho_(0.8)Fe_(17)crystal lattice in creases the saturation magnetization(σs)at T=300 K,but does not significantly affect%at T=4.2 *** ferrimagnetic structure is retained in magnetic fields up to 58 T in the parent compound,while,in the hydride,there is a spin-reorie ntatio n phase transitio n observed at 55 *** is found that the parameter of the in tersublattice exchange interaction decreases significantly in the hydride Sm_(1.2)Ho_(0.8)Fe_(17)Hg_(4.4)(and in the nitride Sm_(1.2)Ho_(0.8)Fe_(17)N_(2.4))which is associated with boosting of the unit-cell volume and distances between magnetic ions.

关键词： intermetallic compound Hydride Crystal structure Magnetization Magnetic phase transition Exchange interaction

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 clinopyroxene 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 isotopes Central asian orogenic belt

Production of super-heavy nuclei in cold fusion reactions

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Chinese Physics C 2021年第4期45卷 301-324页

作者： v.Yu.Denisov i.Yu.Sedykh institute for Nuclear Rescarch Prospect Nauki 4703028 KievUkraine Faculty of Physics Taras Shevchenko National University of KievProspect Glushkova 203022 KievUkraine Financial University under the Goverment of the Russian Federation Leningradsky Prospekt 49125993 MoscowRussian Federation

A model for cold-fusion reactions related to the synthesis of super-heavy nuclei in collisions of heavy projectile-nuclei with a ^(208)Pb target nucleus is *** the framework of this model,the production of the com-pound nucleus by two paths,the di-nuclear system path and the fusion path,are taken into account *** formation of the compound nucleus in the framework of the di-nuclear system is related to the transfer of nucle-ons from the light nucleus to the heavy *** fusion path is linked to the sequential evolution of the nuclear shape from the system of contacting nuclei to the compound *** is shown that the compound nucleus is mainly formed by the fusion path in cold-fusion *** landscape of the potential energy related to the fusion path is discussed in *** landscape for very heavy nucleus-nucleus systems has an intermediate state,which is linked to the formation of both the compound nucleus and the quasi-fission *** decay of the intermediate state is taken into account in the calculation of the compound nucleus production cross sections and the quasi-fission cross *** values of the cold-fusion cross sections obtained in the model agree well with the experimental data.

关键词： super-heavy nuclei production statistical compound-nucleus reactions low energy heavy-ion reactions fusion and fusion-fission reactions