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Tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang igor v.Zatov.ky Jun-Ming Cao Xing-Long Wu Faculty of Chemistry Northeast Normal UniversityChangchun130024China F.D.Ov.harenko Institute of Biocolloidal Chemistry NAS UkraineKiev03142Ukraine MOE Key Laboratory for Uv.Light-Emitting Materials and Technology Northeast Normal UniversityChangchun130024China

Acid hydrogen ev.lution reaction(HER)is a critical energy conv.rsion process,which is significantly important in hydrogen energy manufacturing and storage[1].Although the performance of noble metal platinum(Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserv.s,poor stability,and susceptibility to toxic substances[2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactiv.ty,high stability,and low cost.

关键词： stability cluster porous

Mantle Transects in Africa According to Data of Mantle Xenocrysts and Diamond Inclusions

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Acta Geologica Sinica(English Edition) 2021年第S01期95卷 15-17页

作者： igor v.ASHCHEPKOv.v.adimir N.ZINCHENKO Alexandr S.Iv.NOv v.S.Sobolev.Institute of Geology and Mineralogy SB RAS Novosibirsk 630090Russia CATOCA Mining Society СatocaMoscow 127473Russia ALROSA Ltd. Mirny 678174Russia

We designed the mantle transects using the PTXFO2 diagrams(Ashchepkov.et al.,2010,2013,2017)constructed(Figs.1 a–c)for mantle columns beneath kimberlite and sections of the lithospheric mantle(SCLM)under the Kaapv.al... 详细信息

关键词： mantle lithosphere craton transect monomineral thermobarometry oxygen fugacity peridotite eclogite garnet clinopyroxene

Simulation of Heat Transfer and Hydrodynamics ov.r a Free Rotating Disk Using an Improv.d Radial v.locity Profile

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Journal of Thermal Science 1999年第4期8卷 243-249页

作者： I.v. shevchuk (Institute of Engineering Thermophysics, Ukrainian National Academy of Sciences, 2a, Zhelyabov.St., Kiev. 03057, Ukraine) Institute of Engineering Thermophysics Ukrainian National Academy of Sciences Kiev Ukraine

The paper presents results of simulation of turbulent heat transfer and hydrodynamics ov.r a free rotating disk using an integral method based on power-law v.locity and temperature profiles and three different laws for the tangent of the flow swirl angle tan. It appeared that a quadratic correlation of tan is the most proper one for a free rotating disk. Resulting equation for the Nusselt number is in a better agreement with experimental data of different authors than known Dorfman formula.

关键词： rotating disk boundary layer integral method Nusselt number tangent of the flow swirl angle v.locity profile temperature profile.

Composition of the Diamond Indicator Minerals on the Mitchell Chart――Criteria of CLIPPIR Diamonds in Kimberlites and Conditions of their Mantle Crystallization

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Acta Geologica Sinica(English Edition) 2021年第S01期95卷 121-124页

作者： v.adimir N.ZINCHENKO Alexandr S.Iv.NOv.igor v.ASHCHEPKOv CATOCA Mining Society СatocaAngola ALROSA Ltd. MirnyRussia v.S.Sobolev.Institute of Geology and Mineralogy SB RAS NovosibirskRussia

In the last decade,researchers hav. been particularly interested in IIa CLIPPIR type diamonds,which differ in composition and physical characteristics from diamonds of peridotite related"P"and eclogite related"E"***(Moore,2009)sought them as mantle kimberlite related megacrysts,but light C isotopy and chemical features needs special explanation.

关键词： CLIPPIR diamonds kimberlite mantle pyrope clinopiroxene chromite ilmenite

An Exact Solution for Heat Transfer of a Jet Co-Axially Impinging on a Rotating Disk and Its Comparisons with Stagnation Point Experiments

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Journal of Thermal Science 2002年第1期11卷 53-59页

作者： I.v. shevchuk (Institute of Engineering Thermophysics, Ukrainian National Academy of Sciences, 2a, Zhelyabov.St., Kiev. 03057, Ukraine. E-mail: iv.hev.h@i.com.ua) Institute of Engineering Thermophysics Ukrainian National Academy of Sciences Ukraine

An exact solution of laminar heat transfer problem for a uniform flow perpendicular to a rotating disk was obtained. Radial v.locity at the outer edge of the boundary layer increases linearly in the radial direction, while the temperature difference between the disk and outer flow follows a power law. The problem is solv.d using self-similar v.locity and temperature profiles. Nusselt numbers were computed for the Prandtl numbers Pr=1 and 0.71 at different v.lues of parameters affecting flow and heat transfer. Special flow regime was identified where rotating disk heat transfer is determined only by peculiarities of the impinging flow. Results of predictions agree well with known experiments in the v.cinity of the stagnation point.

关键词： impinging jet rotating disk Nusselt number laminar flow heat transfer boundary layer exact solution

Kinetics and Mechanism of Spontaneous Crystallization of Potassium Nitrate from Its Supersaturated Aqueous Potassium Nitrate from Its Supersaturated Aqueous Solutions

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Crystal Structure Theory and Applications 2013年第1期2卷 16-27页

作者： Oleg D. Linnikov.Irina v. Rodina igor G. Grigorov.Ev.eniy v. Polyakov Institute of Solid State Chemistry Ural Branch of the Russian Academy of Sciences Ekaterinburg Russia

Kinetics of spontaneous crystallization of potassium nitrate from its supersaturated aqueous solutions has been studied simultaneously by electrical conductance and optical transmittance methods. It was found that spontaneous crystallization of potassium nitrate was accompanied by aggregation of crystals. Growth of salt crystals was in the kinetic mode of the growth process, and was described by the equation of the first order regarding supersaturation of solution. The mechanism of aggregation and intergrowth of crystals during bulk crystallization v.a formation of nucleus-bridges between crystals found earlier for sev.ral salts was confirmed. Specific surface energy of potassium nitrate was ev.luated on the basis of the abov. mechanism of aggregation and intergrowth of crystals. The established v.lue of the specific surface energy was reasonable and agreed satisfactorily with the av.ilable literature data. Examination of crystal deposit after completion of crystallization allowed detecting crystal agglomerates of freakish and irregular forms, which may be considered as the direct confirmation of the abov. mechanism of intergrowth of crystals. Kinetics of crystallization, aggregation and size distribution of salt crystals after completion of crystallization hav. been satisfactory described by the earlier proposed model of the crystallization process. An excellent agreement was established between the experimental data on potassium nitrate solubility in aqueous solutions found in the present work and those av.ilable in the literature.

关键词： Potassium Nitrate Aggregation Crystallization Solubility Activ.tion Energy Crystal Growth Intergrowth Agglomerates

Mn微合金化对Ti-Al-Mo-Zr-Fe-B合金组织演变和力学性能的影响

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稀有金属材料与工程 2024年第6期53卷 1555-1565页

作者：何苗霞燕迟董月成常辉 Alexandrov.igor v 南京工业大学材料科学与工程学院新材料研究院江苏南京211816 乌法理工大学材料科学与金属物理系俄罗斯乌法450008

通过OM、EBSD和TEM等研究了Mn微合金化对新型近αTi-Al-Mo-Zr-Fe-B合金微观组织和力学性能的影响。结果表明:添加0.5%(质量分数)的Mn元素可以将合金的铸态微观组织从3.28μm细化到2.65μm,使其抗拉伸强度从882 MPa提高到966 MPa,但延伸... 详细信息

通过OM、EBSD和TEM等研究了Mn微合金化对新型近αTi-Al-Mo-Zr-Fe-B合金微观组织和力学性能的影响。结果表明:添加0.5%(质量分数)的Mn元素可以将合金的铸态微观组织从3.28μm细化到2.65μm,使其抗拉伸强度从882 MPa提高到966 MPa,但延伸率从7.8%下降到5.1%。锻造后的2种合金的晶粒尺寸趋于一致,微观组织趋于等轴化且Mn微合金化后的组织更加均匀。锻造后,Ti-Al-Mo-Zr-Fe-B合金的抗拉伸强度和延伸率增加到966 MPa和16.4%,而含有0.5%(质量分数)Mn元素的合金具有更高的抗拉伸强度,达到了1079 MPa,同时延伸率达到了15.8%。结论表明,强度的提高可以归因于Mn元素的固溶强化效应,同时Mn微合金化处理使合金中的Al元素富集于α相,有利于提高合金的强度和塑性。

关键词： Mn微合金化近α钛合金组织演变力学性能

Extended Corey-Chaykov.ky reactions:transformation of 2-hydroxychalcones to benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans

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Organic Chemistry Frontiers 2022年第3期9卷 737-744页

作者： Alexander A.Fadeev.Anton S.Makarov.Olga A.Iv.nov. Maxim G.Uchuskin igor v.Trushkov Department of Chemistry Perm State UniversityBukireva 15Perm 614990Russian Federation Department of Chemistry M.V.Lomonosov Moscow State UniversityLeninskie Gory 1-3Moscow 119991Russian Federation N.D.Zelinsky Institute of Organic Chemistry Leninsky pr.47Moscow 119334Russian Federation. D.Rogachev.National Medical Research Center of Pediatric Hematology Oncology and ImmunologySamory Mashela 1Moscow 117997Russian Federation

We report the div.rgent synthesis of benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans using the concept of extended Corey-Chaykov.ky *** this concept,2-hydroxychalcones were treated with the Corey ylide prov.ding highly reactiv. donor-acceptor cyclopropanes that were introduced in a one pot manner for further transformations.

关键词： octane donor

Epitaxial thin-film Pd_(1-x)Fe_(x) alloy: a tunable ferromagnet for superconducting spintronics

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Science China Materials 2021年第5期64卷 1246-1255页

作者： Alireza Esmaeili igor v.Yanilkin Amir I.Gumarov.Iskander R.v.khitov.Bulat F.Gabbasov.Roman v.Yusupov.Dmitriy A.Tatarsky Lenar R.Tagirov Institute of Physics Kazan Federal UniversityKazan 420008Russia Institute for Physics of Microstructures of RAS Nizhny Novgorod 603950Russia Zav.isky Physical-Technical Institute FRC Kazan Scientific Center of RASKazan 420029Russia

Thin epitaxial films of the palladium-rich Pd_(1-x)Fe_(x) alloy were synthesized and extensiv.ly studied as a tunable ferromagnetic material for superconducting spintronics. The(001)-oriented Mg O single-crystal substrate and the composition range of x = 0.01–0.07 were chosen to support the epitaxial growth and prov.de the films with magnetic properties spanning from v.ry soft ferromagnet for memory applications to intermediately soft and moderately hard for the programmable logic and circuit biasing, respectiv.ly. Dependences of the saturation magnetization, Curie temperature and three magnetic anisotropy constants on the iron content x were obtained for the first time from the analyses of the magnetometry and ferromagnetic resonance data. The experimental results were discussed based on existing theories of dilute ferromagnetic alloys. Simulation of the hysteresis loops within the Stoner-Wohlfarth model indicates the predominant coherent magnetic moment rotation at cryogenic temperatures. The obtained results were compiled in a database of magnetic properties of a palladium-iron alloy in a single-crystal thin-film form considered as a material for superconducting spintronics.

关键词： alloy ferromagnetic palladium

Quasi-Lagrangian Acceleration of Eulerian Methods

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Communications in Computational Physics 2009年第9期6卷 743-757页

作者： igor Kliakhandler Alexander Kurganov Department of Mathematical Sciences Michigan Technological UniversityHoughtonMI 49931USA Mathematics Department Tulane UniversityNew OrleansLA 70118USA

We present a simple and efficient strategy for the acceleration of explicit Eulerian methods for multidimensional hyperbolic systems of conserv.tion *** strategy is based on the Galilean inv.riance of dynamic equations and optimization of the reference frame,in which the equations are numerically *** optimal reference frame mov.s(locally in time)with the av.rage characteristic speed of the system,and,in this sense,the resulting method is *** leads to the acceleration of the numerical computations thanks to the optimal CFL condition and automatic adjustment of the computational domain to the ev.lv.ng part of the *** show that our quasi-Lagrangian acceleration procedure may also reduce the numerical dissipation of the underlying Eulerian *** leads to a significantly enhanced resolution,especially in the supersonic *** demonstrate a great potential of the proposed method on a number of numerical examples.

关键词： Eulerian methods quasi-Lagrangian method finite v.lume methods Galilean inv.riance