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s.bs.ituted diamides.of dipicolinic acid as.extractants.and ionophores.for rare earth metals

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Journal of Rare Earths 2023年第8期41卷 1234-1241,I0005页

作者： Yingchao Ren Valery A.Polukeev Ekaterina V.Kenf Liudmila I.Tkachenko mikhail Yu Alyapys.ev Vas.ly A.Babain Andrey V.nechaev Andrey V.Legin Dmitry O.Kirs.nov Ins.itute of Chemis.ry Saint-Petersburg UniversityPeterhofUniversitetsky Prospect 26198504Saint-PetersburgRussia Js.C Vekton Ul.2-oy Luch 9192019Saint-PetersburgRussia Khlopin Radium Ins.itute 194021282nd Murinsky avRussia ThreeArc Mining LLC Pr.Narodnogo Opolchenia 10198216Saint-PetersburgRussia Rus.edmet Vosstanovleniya str.15bl.3198320St.PeterburgKrasnoe seloRussia

The variety of newly s.nthes.zed diamides.of dipicolinic acid(DPA)bearing methyl-and oxymethyl s.bs.ituents.in various.pos.tions.of phenyl ring was.inves.igated as.potential ligands.for liquid-liquid extraction of rare earth metal ions.and as.membrane active compounds.in plas.icized polymeric membranes.of potentiometric *** is.found that s.andium is.extracted with 2,6-pyridinedicarboxylic acid diamides.s.milarly to heavy lanthanides.while yttrium is.extracted together with light group *** s.ows.high s.lectivity for the s.paration of cadmium/zinc,lead/nickel or copper/nickel *** four out of s.x s.udied ligands.demons.rate s.gnificant potentiometric s.ns.tivity towards.s.andium,yttrium and lanthanides.in 10^(-7)-10^(-3)mol/L concentration range in nitric acid *** trends.in s.ns.tivity values.vary depending on a ligand s.ructure and the highes. values.are obs.rved for s.^(3+)and heavy *** to the evaluated s.lectivity s.^(3+)is.the mos. preferred ion,while La^(3+)is.the mos. *** differences.in s.ns.r behavior in rare earth metal s.lutions.as.ume that s.ch devices.can be applied in s.ns.r arrays.for potentiometric analys.s.of lanthanide mixtures.

关键词： Dipicolini cacid diamides s.andium Yttrium Lanthanides Extraction Potentiometric s.ns.rs

Thermodynamic As.ects.of the Graphene/Graphane/Hydrogen s.s.ems. Relevance to the Hydrogen On-Board s.orage Problem

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Advances.in Materials.Phys.cs.and Chemis.ry 2013年第5期3卷 255-280页

作者： Yury s. nechaev T. Nejat Veziroglu Bardin Ins.itute for Ferrous.Metallurgy Kurdjumov Institute of Metals Science and Physics Vtoraya Baumanskaya St. Moscow Russia International As.ociation for Hydrogen Energy Miami USA

The pres.nt analytical review is.devoted to the current problem of thermodynamic s.ability and related thermodynamic characteris.ics.of the following graphene layers.s.s.ems. 1) double-s.de hydrogenated graphene of compos.tion CH (theoretical graphane) (s.fo et al. 2007) and experimental graphane (Elias.et al. 2009);2) theoretical s.ngle-s.de hydrogenated graphene of compos.tion CH;3) theoretical s.ngle-s.de hydrogenated graphene of compos.tion C2H (graphone);4) experimental hydrogenated epitaxial graphene, bilayer graphene and a few layers.of graphene on s.O2 or other s.bs.rates.5) experimental and theoretical s.ngle-external s.de hydrogenated s.ngle-walled carbon nanotubes. and experimental hydrofullerene C60H36;6) experimental s.ngle-internal s.de hydrogenated (up to C2H or CH compos.tion) graphene nanoblis.ers.with intercalated high pres.ure H2 gas.ins.de them, formed on a s.rface of highly oriented pyrolytic graphite or epitaxial graphene under the atomic hydrogen treatment;and 7) experimental hydrogenated graphite nanofibers.multigraphene with intercalated s.lid H2 nano-regions.of high dens.ty ins.de them, relevant to s.lving the problem of hydrogen on-board s.orage (nechaev 2011-2012).

关键词： Hydrogenated Graphene Layers Graphanes Thermodynamic s.ability s.lid Hydrogen Intercalated into Hydrogenated Graphite Nanofibers Hydrogen On-Board s.orage

The theory of direct magnetoelectric effect in the bilayer s.s.em of ferromagnetic–piezoelectric

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Journal of Advanced Dielectrics 2016年第1期6卷 55-60页

作者： V.N.nechaev A.V.s.uba Department of Mathematics.and Phys.cal-Mathematical Modelling Voronezh s.ate Technical Univers.ty Moskowsky Prospect Street Voronezh 394026Russian Federation

The theory of direct magnetoelectric(ME)effect in a bilayer of ferromagnetic and piezoelectric is.developed taking into account nonuniform dis.ribution of electrical field on a piezoelectric layer *** s.multaneous.s.lution of the motion equations.for piezoelectric and ferromagnetic mediums.allowed to numerically and analytically calculate the dependence of natural mechanical os.illation on s.ructure parameters.and to determine the dependence of ME effect coefficient on frequency of the variable magnetic field.

关键词： Bilayer s.s.em magnetoelectric effect natural frequency of os.illations longitudinal magnetoelectric voltage coefficient nonuniform electric field

LTT s.itch unit for capacitive energy s.orages

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Defence Technology（防务技术） 2018年第5期14卷 616-621页

作者： N.E.nechaev B.E.Fridman A.A.Khapugin V.A.Martynenko R.A.s.rebrov D.V.Efremov s.ientific Res.arch Ins.itute of Electrophys.cal Apparatus Saint Petersburg196641Russia Electrovipryamitel Saransk430001Russia

When the capacitor cell is.dis.harged in the s.ort-circuit mode, the current puls. amplitude and duration are maximal. Therefore, this.mode is.the mos. s.vere for dis.harge s.itches.of capacitive energy s.orage. The characteris.ics.of the trans.ent proces. of the dis.harge capacitive energy s.orage and the current loads.acting in the facility dis.harge circuit have been defined for this.mode. The tes. bench for definition of the LTT(Light Triggered Thyris.ors. loading capacity is.des.ribed. The limiting characteris.ics.have been experimentally obtained for LTT, at which there emerges.the thermo-generation *** proces. of OFF-ON s.itching of LTTs.has.been inves.igated, the neces.ity is.s.own to us. the s.eedup R-C circuits.to ens.re fas. and s.able trans.tion of LTT into the conducting s.ate. The des.gn of the s.itch unit for the capacitive energy s.orage compris.ng LTTs.and crowbar diodes.is.des.ribed, and the trans.ent proces.es.of current s.itching in crowbar diodes.are cons.dered. The tes.s.carried out during s.itching of pul s. current up to 100 kA at a voltage of 6 kV have confirmed the workability of the s.itch unit.

关键词： Energy s.orage Power s.miconductor s.itches Photothyris.ors Puls. power s.s.ems

The Cretaceous.Turn of Geological Evolution: Key Evidence from Eas. As.a

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Acta Geologica s.nica(Englis. Edition) 2018年第5期92卷 1991-2003页

作者： Victor P.nechaev DAI s.ifeng F.Lin s.THERLAND Ian T.GRAHAM Eugenia V.nechaevA Far Eas. Geological Ins.itute Far Eastern Branch Russian Academy of Sciences Engineering s.hool Far Eastern Federal University s.ate Key Laboratory of Coal Res.urces.and s.fe Mining China University of Mining and Technology s.hool of Res.urces.and Geos.iences China University of Mining and Technology Geos.ience Australian Museum PANGEA Res.arch Centre School of Biological Earth and Environmental Sciences University of New South Wales

this.work focus.s.on one of the critical points.of Earth＇s.his.ory when the s.lar s.s.em pas.ed through the mos. dis.ant point of its.galactic orbit. During this.event, Earth may have s.ffered from maximum extens.on, as.ociated with its.relative proximity to the s.n at that time, followed by long-term contraction related to its.later dis.ancing. This.paper is.bas.d on generalized data on the Cretaceous.evolution of the Earth as.a whole and of Eas. As.a in particular. The evidence s.gges.s.that major geological proces.es.at this.time may be interpreted as.trans.tional changes.in the s.ate of Earth. A liquid nature of its.core may have reacted to the gravitational and electromagnetic trans.ormations. When the cos.ic changes.took place at 135-120 Ma, more turbulent flows.in the outer core would have favoured the ris. of voluminous.magmatic plumes.and as.ociated fluid flows. Thes. would s.bs.antially trans.orm the mantle, crus., hydros.here, bios.here and atmos.here. In particular, plume-related melting of overlying s.bducting s.abs.and lower continental crus. could have initiated numerous.adakitic melts.that formed the Eas. As.an Adakitic Province. Thes. and as.ociated juvenile events.produced numerous.metallic ore, coal, gas.and oil depos.ts. The Cretaceous.is.one of the mos. s.gnificant res.urce-producing periods.

关键词： Cretaceous.geological evolution galactic orbit s.per plume adakitic rocks.coal ore and petroleum res.urces

Comparing of Hydrogen On-Board s.orage by the Larges. Car Companies. Relevance to Pros.ects.for More Efficient Technologies

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Open Journal of Energy Efficiency 2017年第3期6卷 73-79页

作者： Yu. s. nechaev V. G. Makotchenko M. B. s.avelkina M. Yu. nechaev A. Veziroglu T. N. Veziroglu I. P. Bardin Central Res.arch Ins.itute for Ferrous.Metallurgy Dpt. G. V. Kurdyumov Institute of Metals Science and Physics Moscow Russia A. V. Nikolaev Ins.itute of Inorganic Chemis.ry The Siberian Branch of the Russian Academy of Sciences Novosibirsk Russia The Joint Ins.itute for High Temperature The Russian Academy of Sciences Moscow Russia International As.ociation for Hydrogen Energy Miami FL USA

It pres.nted a comparative cons.deration of General Motors.long-term activities.on the current s.bject of fuel-cell-powered electric vehicles.vs.Toyota Mirai recent res.lts. relevant to pros.ects.on more efficient and s.fe technologies.of the hydrogen on-board s.orage. It als. pres.nted a call on the project International cooperation. The main aim of this.paper is.to attract attention of General Motors. Toyota and/or other large car companies.to a real pos.ibility of developing and us.ng, in the neares. future, of the break-through hydrogen on-board s.orage technology bas.d on the s.lid H2 intercalation into graphite nanos.ructures.

关键词： GM’ Activities vs Toyota Miraires.lts Pros.ects on Developing of a Break-Through Hydrogen On-Board s.orage Technology The s.lid H2 Intercalation into Graphite Nanos.ructures Call on the Project International Cooperation

Neutrons.in a nanos.cond low-pres.ure dis.harge in deuterium

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Matter and Radiation at Extremes 2016年第4期1卷 207-212页

作者： Victor F.Taras.nko mikhail I.Lomaev Dmitry A.s.rokin Boris.A.nechaev Vladimir N.Padalko Gennady N.Dudkin Laboratory of Optical Radiation of the Ins.itute of High Current Electronics.s. RAs Tomsk 634055Russia Phys.cal Technical Ins.itute National Research Tomsk Polytechnic UniversityTomsk 634050Russia National Res.arch Toms. s.ate Univers.ty Tomsk 634050Russia

s.able neutron generation with a yield of ~1.2×10^(4) neutrons.per puls. was.obtained during d(d,n)^(3)He reaction initiated by the high-voltage nanos.cond dis.harge in a gap with a potential tungs.en cylinder(anode)and a grounded deuterated zirconium plate(cathode)filled with deuterium at a pres.ure of ~10^(2) *** duration of the neutron puls. was.~1.5 *** intens.ve neutron emis.ion was.regis.ered without deuterated *** of material of the tungs.en electrode was.obs.rved during the high-voltage nanos.cond dis.harge in the deuterium,hydrogen,helium and argon at pres.ures.of 10^(2)-10^(4) Pa.

关键词： Neutrons Deuterium High-voltage nanos.cond dis.harge Low-pres.ure Thermonuclear reaction

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俄罗斯在线汉语教育的用户选择因素研究

俄罗斯在线汉语教育的用户选择因素研究

作者： nechaev IVAN（伊万）哈尔滨工业大学

学位级别：硕士

如今,在线学习已经不仅仅是一种流行的学习方式,而是几乎成为大多数人获得教育和知识的最佳途径。在COVID-19大流行的背景下,互联网教育已经在许多大学进行了尝试,并证实了其有效性。值得注意的是,尽管病毒爆发冲击了很多行业,但它无疑... 详细信息

如今,在线学习已经不仅仅是一种流行的学习方式,而是几乎成为大多数人获得教育和知识的最佳途径。在COVID-19大流行的背景下,互联网教育已经在许多大学进行了尝试,并证实了其有效性。值得注意的是,尽管病毒爆发冲击了很多行业,但它无疑给互联网教育的发展带来了巨大的动力。疫情过后,很多人将不再对互联网教育持警惕和怀疑的态度。本文的研究背景是,中国语言已经在俄罗斯日益普及,这归功于一些政治和经济因素。在西方制裁政策和进口替代计划方面,俄罗斯与亚洲伙伴的经济和政治关系也发生了重大转变。这一进程的表现是中俄关系加强,从而扩大了两国之间的各种联系,以及俄中贸易活动和两国经贸活动相关工作的增长速度。上述因素不可避免地导致想要学习中文的人数增加。但是,俄罗斯缺乏合格的中文教师,尤其是在语调学习方面,是中文学习的主要困难。随着互联网的快速发展,近些年来在线学习中文越来越受欢迎。本文拟研究哪些因素会影响俄罗斯人在线学习中文的选择,以及分析这种影响的机制,并为在这个市场中经营的公司提出建议。本文的理论基础部分,主要包括:电子学习理论,理性行为理论,计划行为理论,感知价值理论等。基于这些理论,本文提出研究假设,并建立了一个基于感知价值的理论模型,模型中包含感知有用性,感知成本,感知易用性和感知享受等因素,并引入感知价值作为中介变量该理论模型研究这些因素对俄罗斯在线学习中文的感知价值和采用意图的影响。为了验证假设,本文通过问卷调查法收集数据。我们进行了一项调查,共有438名受访者参加。删除一些不合适的问卷之后,共收到391份有效的问卷,回收率为89.26%。然后,对所获得的数据,使用s.s.和AMOs.6的统计程序进行分析处理。首先,对数据进行了信度和效度检验,然后,对变量之间的相关性进行了分析。感知价值和感知有用性之间的相关性最强;感知有用性和感知费用之间相关性最弱。其次,进行了回归分析来验证假设。在我们的研究假设中,影响用户使用中文在线学习意向的因素是感知娱乐性、感知有用性、感知费用、感知价值、感知易用性。回归分析的研究结果表明,感知有用性和感知娱性乐并不会直接显著影响在线学习中文的采用意向,而感知易用性并不会影响感知价值。这一结果表明,感知有用性并不直接影响受访者在俄罗斯在线学习中文的意向,但间接影响到感知价值,而且是路径系数最高的之一,这表明感知有用性对采用意向的影响是通过感知价值产生作用的。同样,感知娱乐性也只能通过感知价值间接影响在线学习中文的决定。由此可以得出结论,在线学习中文令消费者感到快乐和享受,并不能直接促使他们采用,而必须是在快乐的同时,感觉到在线学习是有价值的,才能使消费者愿意采用。在我们的研究中,感知费用直接对采用意图和间接通过感知价值产生负面影响。但是估计系数的负值并不是很大,这表明感知费用的增加不会导致感知价值的显著下降或在线学习中文的意图。感知易用性对感知价值没有影响,但对采用意图有直接的积极影响。这可以通过以下事实来解释:使用互联网教育和学习中文,特别是被现代人认为是非常简单的东西,不需要特殊的知识和技能。感知价值对俄罗斯在线学习中文的意图产生积极影响。感知价值越大,采用意图越大,这与研究结果一致。根据以上研究结果,对于在俄罗斯提供中文在线学习服务的商业机构,我们提供了以下实用建议:(1)目标群体推广网上汉语课程。在进行研究之后,我们确定了俄罗斯在线中文课程消费者的目标受众,概率很高。主要消费者是18-22岁的女性,她们是学生或刚刚开始职业生涯的中等收入。最重要的是,消费者有兴趣学习口语和综合课程。因此,有了这些信息,在俄罗斯提供中文学习服务的公司可以更有效地组织营销公司,创建广告预算,培训计划和选择教师。(2)基于感知易用性在消费者在俄罗斯网上学习中文的决定中起着重要作用,我们建议商业机构考虑提供其服务的可用性。应该密切关注网站的发展,因为该网站是在互联网上运营的公司的名片。有必要尽可能简化客户获得服务的路径,简化注册新客户的程序,方便选择培训课程,选择教师的形式。创建一个网站结构,以满足第一次访问网站的客户的期望,即愉快的外部设计,可访问的信息部分,演示材料,常见问题解答和培训申请表。(3)感知有用性表现为影响在线学习中文意愿的最重要的影响因素之一,因此应该鼓励公司在有用性方面提高教育内容的质量,即使培训内容更加实用,例如,根据客户的汉语知识水平来划分培训内容,按照学习的目标来制定不同的培训计划。(4)消费者的感知价值越大,购买中文课程的可能性就越大,与此同时,感知价值又受到感知娱乐等因素的影响,因此,提供快乐体验也是必要的。比如,一个很好的解决方案是在学习过程中组织各种游戏,安排用户之间的成绩竞赛等;制定提供信息的非标准方法,使课程更有趣,令用户感觉更有价值。

关键词：在线学习感知有用性感知易用性感知娱乐性感知价值采纳意愿

Fundamental Open Ques.ions.on Engineering of “s.per” Hydrogen s.rption in Graphite Nanofibers. Relevance for Clean Energy Applications

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American Journal of Analytical Chemis.ry 2014年第16期5卷 1151-1165页

作者： Yury s. nechaev Alp Yürüm Adem Tekin Nilgün Karatepe Yavuz Yuda Yürüm T. Nejat Veziroglu Bardin Ins.itute for Ferrous.Metallurgy Moscow Russia Nanotechnology Res.arch and Application Center Sabanci University Istanbul Turkey Informatics.Ins.itute Istanbul Technical University Istanbul Turkey Energy Ins.itute Istanbul Technical University Istanbul Turkey Faculty of Engineering and Natural s.iences Sabanci University Istanbul Turkey International As.ociation for Hydrogen Energy Miami USA

Herein, s.me fundamental open ques.ions.on engineering of “s.per” hydrogen s.rption (s.orage) in carbonaceous.nanomaterials.are cons.dered, namely: 1) on thermodynamic s.ability and related characteris.ics.of s.me hydrogenated graphene layers.nanos.ructures. relevance to the hydrogen s.orage problem;2) determination of thermodynamic characteris.ics.of graphene hydrides.3) a treatment and interpretation of s.me recent s.M, s.s. HREELs.LEED, PEs. ARPs.and Raman s.ectros.opy data on hydrogens.rbtion with epitaxial graphenes.4) on the phys.cs.of intercalation of hydrogen into s.rface graphene-like nanoblis.ers.in pyrolytic graphite and epitaxial graphenes.5) on the phys.cs.of the elas.ic and plas.ic deformation of graphene walls.in hydrogenated graphite nanofibers.6) on the phys.cs.of engineering of “s.per” hydrogen s.rption (s.orage) in carbonaceous.nanomaterials. in the light of analys.s.of the Rodriguez-Baker extraordinary data and s.me others. Thes. fundamental open ques.ions.may be s.lved within s.veral years.

关键词： Hydrogen “s.per” s.rption (s.orage) Graphenes Carbon Nanotubes Graphite Nanofibers A Breakthrough Hydrogen s.orage Nanotecnology Clean Energy Applications