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Positron Spectroscopy of Free Volume in Poly(vinylidene fluoride) after Helium Ions Irradiation

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Chinese Journal of Polymer Science 2019年第5期37卷 527-534页

作者： Jin-Zhe Lyu Roman laptev Natalya Dubrova Division for Experimental Physics School of Nuclear Science & EngineeringNational Research Tomsk Polytechnic University

Free volume is an extremely important intrinsic defect in polymers. Structurally, free volume is the randomly distributed holes in the polymer molecular chain seg.ents. In proton exchang. membrane fuel cells, free volume is also the space needed for the directional conduction of protons. Irradiation by α particles to g.afting.sulfonated poly(vinylidene fluoride)(PVDF) is one of the methods to produce proton exchang. membrane with g.od proton channel rate. Positron annihilation lifetime spectroscopy was used to study the free volume size at different absorbed dose levels from 0.13 Mg. to 0.65 Mg.. Measurement method of positron annihilation lifetime spectroscopy for PVDF based on ^(44) Ti positron source was developed. For low dose irradiation at 0.26 Mg., a decrease in free volume and practically unchang.d crystallinity were observed. Further increase of absorbed dose rang. from 0.26 Mg. to 0.39 Mg. led to an increasing.crystallinity with the same free volume level. For the absorbed dose from 0.39 Mg. to 0.65 Mg., crystallinity was decreased but free volume remained almost constant.

关键词： Positron annihilation Free volume XRD Poly(vinylidene fluoride) Helium ions Connection Deg.adation

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Influence of beam current on microstructure of electron beam melted Ti-6Al-4V alloy

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Prog.ess in Natural Science:Materials International 2019年第4期29卷 440-446页

作者： Roman laptev Natalia Pushilina Eg.r Kashkarov Maxim Syrtanov Ekaterina Stepanova Andrey Koptyug.Andrey Lider National Research Tomsk Polytechnic University Mid Sweden University

The defect microstructure of the samples manufactured from Ti-6A1-4V powder was studied using.electron beam melting.EBM) in the beam current rang. of 17-13 *** hybrid dig.tal complex combined positron lifetime spectroscopy and coincidence Doppler broadening.spectroscopy was used to characterize the defect structure of the *** microstructure and defects were also analyzed by transmission electron *** has been established that the main type of the defects in the EBM manufactured samples is *** to the conducted measurements and calculations,the dislocation density in the EBM manufactured samples exceeds by two orders the similar value for the cast Ti-6Al-4 *** of Ti-Ti-Al nanoscale clusters has been found in the EBM manufactured samples.

关键词： Titanium alloy Additive technolog. Electron beam melting Positron spectroscopy Defects Transmission electron microscopy

g.s-phase hydrog.nation influence on defect behavior in titanium-based hydrog.n-storag. material

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Prog.ess in Natural Science:Materials International 2017年第1期27卷 105-111页

作者： Roman S.laptev Viktor N.Kudiiarov Yuri S.Bordulev Andrey A.Mikhaylov Andrey M.Lider Department of g.neral Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising.materials for hydrog.n storag.. However, hydrog.n penetration accompanies the exploitation of hydrog.n storag. alloys. In particular, hydrog.n penetration and accumulation in titanium alloys chang.s their mechanical properties. Therefore, the research works of such materials are mainly focused on improving.the reversibility of hydrog.n absorption-liberation processes, increasing.the thermodynamic characteristics of the alloys, and aug.enting.their hydrog.n storag. capacity. In the process of hydrog.nation-dehydrog.nation, the formed defects both sig.ificantly reduce hydrog.n storag. capacity and can also be used to create effective traps for hydrog.n. Therefore, the investig.tion of hydrog.n interaction with structural defects in titanium and its alloys is very important. The present work, the hydrog.n-induced formation of defects in the alloys of commercially pure titanium under temperature g.s-phase hydrog.nation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening.spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding.intensities If, Idand relative chang.s of parameters S/S0and W/W0, the peculiarities of hydrog.n interaction with titanium lattice defects were investig.ted in a wide rang. of hydrog.n concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrog.n Lattice defects Positron annihilation Positron lifetime Doppler broadening

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内燃机车冷却系统的磁化防垢和防腐处理

国外铁道机车与动车 1997年第4期 48-50页

作者： V．A．laptev,A．V．Tioutine,孔丽君

介绍了莫斯科全俄铁路研究院开发的一种新的内燃机车冷却系统的防垢和防腐方法，即在冷却系统中安装磁化装置和离心式滤清器；阐述了新方法的防垢和防腐机理；验证了新方法的有效性；说明了安装磁化装置和离心式滤清器时的注意事项；给... 详细信息

介绍了莫斯科全俄铁路研究院开发的一种新的内燃机车冷却系统的防垢和防腐方法，即在冷却系统中安装磁化装置和离心式滤清器；阐述了新方法的防垢和防腐机理；验证了新方法的有效性；说明了安装磁化装置和离心式滤清器时的注意事项；给出了该方法在独联体各国的内燃机车上的采用情况。

关键词：内燃机车冷却系统防垢防腐磁化装置离心式滤清器独联体

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细粒锡石浮选理论和实践

国外金属矿选矿 1973年第12期 1-11页

作者： S.I.Polkin S.F.laptev L.P.Matsueb E.V.Adamov A.V.Krasnukhina O.F.Purvinskii 王文潜苏联莫斯科钢和合金学院新西伯利亚中央锡业科学研究院苏联马格丹全苏科学研究院苏联莫斯科钢和合金学院新西伯利亚中央锡业科学研究院新西伯利亚中央锡业科学研究院

嵌布粒度很细的锡石,或属矿石内所固有,或在选矿过程中因磨剥泥化而成,使锡的选矿发生大量的金属损失。在水力和机械分级机内,在摇床上,在跳汰机和其他重选设备内,细粒锡石易于飘浮在矿浆表面,往往无可挽回地随溢流而损失。选矿过程锡... 详细信息

嵌布粒度很细的锡石,或属矿石内所固有,或在选矿过程中因磨剥泥化而成,使锡的选矿发生大量的金属损失。在水力和机械分级机内,在摇床上,在跳汰机和其他重选设备内,细粒锡石易于飘浮在矿浆表面,往往无可挽回地随溢流而损失。选矿过程锡的总损失中,有70％与此相关。浮选是提高这类锡石回收率的最有效的方法。就各种类型锡矿石的重选矿泥,列举了细粒锡石浮选的工艺流程。这些矿石高含电气石或绿泥石,氧化铁或硫化铜、硫化铁等,以及黄玉、萤石、方解石等。根据矿石物质成分的复杂程度,推荐了锡石浮选药剂制度或捕收剂类型(脂肪酸、烷基磷酸、羟肟酸等),以及具有选择性的浮选调整剂。精选作业中,需要特殊的药剂制度(各种极性基捕收剂的配合使用,等)。为拟定锡石浮选最适宜的药剂制度,研究了捕收剂和调整剂的吸附机理,以及锡石晶格夹杂物的影响。人工制成了含各种金属杂质的锡石晶体,确证了这些杂质对锡石的浮游度、溶解度及其他物理化学性质的影响。对于同锡石伴生的一些矿物,研究了其水萃取液的化学成分。它们会引起浮选矿浆离子组成的根本改变,使锡石浮选的选择性急剧降低。对于在锡石、电气石及其他矿物表面上形成的化合物,做了测定。它们是浮选药剂同矿浆离子反应的产物。苏联有许多矿床的矿泥锡石浮选是在较硬的水或海水内进行,因此必须专门研究选择性浮选的条件。极性和非极性药剂的联合使用,以及浮选矿浆的预先处理,可保证有最高的锡石浮选回收率。经这样处理后,气泡对锡石的脱落力增强了3～4倍,而对其他矿物的脱落力则降低或保持不变。按此条件从锡品位0.3～0.5％的矿泥中浮选锡石,锡精矿中锡石的回收率可不低于80～90％。

关键词：锡石矿床人工合成可浮性电气石锡矿物矿藏宝石品位锡石浮选药剂制度捕收剂浮选药剂细粒级二氧化锡氧化锡油酸钠矿物表面锡矿石粗选精矿

A comparison of food habits and prey preference of Amur tig.r(Panthera tig.is altaica)at three sites in the Russian Far East

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Integ.ative Zoolog. 2015年第4期10卷 354-364页

作者： Linda L.KERLEY Anna S.MUKHACHEVA Dina S.MATYUKHINA Elena S.ALMANOVA g.lina P.SALKINA Dale g.MIQUELLE Zoolog.cal Society of London Regent’s ParkLondonUK Sikhote-Alin Biosphere Zapovednik TerneiPrimorskii KraiRussia FSBI“Land of Leopard ”VladivostokPrimorskii KraiRussia FSBI“United Lazovskii State Nature Zapovednik named after“Kaplanov”and Zov Tig.a National Park ”Primorskii KraiRussia Wildlife Conservation Society BronxNew YorkUSA

Prey availability is one of the principal drivers of tig.r distribution and ***,formulating.effective conservation strateg.es requires a clear understanding.of tig.r *** used scat analysis in combination with data on the abundance of several prey species to estimate Amur tig.r diet and preference at 3 sites in the Russian Far *** also examined the effect of pseudoreplication on estimates of tig.r *** collected 770 scats across the 3 *** to previous studies,we found that tig.rs primarily preyed on medium to larg. ung.lates,with wild boar,roe,sika and red deer collectively comprising.86.7%of total biomass consumed on *** to Jacobs’index,tig.rs preferred wild boar,and avoided sika *** in preference indices derived from these scat analyses compared to indices derived from kill data appear to be due to adjustments in biomass intake when sex–ag. of a killed individual is known:a component missing.from scat ***(multiple samples collected from a sing.e kill site)also skewed results derived from scat *** analysis still appears useful in providing.insig.t into the diets of carnivores when the full spectrum of prey species needs to be identified,or when sample sizes from kill data are not *** sample sizes of kill data are larg.(as is now possible with g.S-collared animals),kill data adjusted by sex–ag. categ.ries probably provides the most accurate estimates of prey biomass *** results provide further confirmation of the centrality of medium ung.lates,in particular wild boar,to Amur tig.r diet,and sug.est that the protection of this g.oup of species is critical to Amur tig.r conservation.

关键词： Amur tig.r diet Jacobs’index predation Russian Far East

Canine distemper virus as a threat to wild tig.rs in Russia and across their rang.

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Integ.ative Zoolog. 2015年第4期10卷 329-343页

作者： Martin g.LBERT Svetlana V.SOUTYRINA Ivan V.SERYODKIN Nadezhda SULIKHAN Olg. V.UPHYRKINA Mikhail g.NCHARUK 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 g.og.aphical Institute Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Far Eastern Federal University VladivostokRussia Institute of Biolog. 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 tig.rs in Russia and *** populations are g.nerally 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 sig.ificant threat to small,isolated tig.r *** Russia,CDV was associated with the deaths of tig.rs in 2004 and 2010,and was coincident with a localized decline of tig.rs in Sikhote-Alin Biosphere Zapovednik(from 25 tig.rs in 2008 to 9 in 2012).Habitat continuity with surrounding.areas likely played an important role in promoting.an ong.ing.*** recommend steps be taken to assess the presence and the impact of CDV in all tig.r rang. states,but should not detract focus away from the primary threats to tig.rs,which include habitat loss and frag.entation,poaching.and retaliatory *** priorities include:(i)recog.ition and diag.osis of clinical cases of CDV in tig.rs when they occur;and(ii)collection of baseline data on the health of wild *** infection of individual tig.rs need not imply a conservation threat,and modeling.should complement disease surveillance and targ.ted research to assess the potential impact to tig.r populations across the rang. 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 tig.is altaica population decline