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Tungsten 2024年第4期6卷 657-662页

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

Acid hydrogen evolution reaction(HER)is a critical energy conversion 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 reserves,poor stability,and susceptibility to toxic substances[2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

关键词： stability cluster porous

Atmospheric and Coupled Model Intercomparison in Terms of Amplitude—Phase Characteristics of Surface Air Temperature Annual Cycle

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Advances in Atmospheric Sciences 2004年第6期21卷 837-847页

作者： Alexey v. ELISEEv igor I. MOKHOv Konstantin G. RUBINSTEIN Maria S. GUSEvA A. M. Obukhov Institute of Atmospheric Physics RAS 3 Pyzhevsky 119017 Moscow RussiaA. M. Obukhov Institute of Atmospheric Physics RAS 3 Pyzhevsky 119017 Moscow RussiaRussian Hydrometcentre 9 Bol. Predtechensky 123242 Moscow RussiaRussian Hydrometcentre 9 Bol. Predtechensky 123242 Moscow Russia

A model intercomparison in terms of surface air temperature annual cycle amplitude-phase characteristics (SAT AC APC) is performed. The models included in the intercomparison belong to two groups: five atmospheric models with prescribed sea surface temperature and sea ice cover and four coupled models forced by the atmospheric abundances of anthropogenic constituents (in total six coupled model simulations). Over land, the models, simulating higher than observed time averaged SAT, also tend to simulate smaller than observed amplitude of its annual and semiannual harmonics and (outside the Tropics) later-than-observed spring and autumn moments. The models with larger (smaller) time averaged amplitudes of annual and semiannual harmonics also tend to simulate larger (smaller) interannual standard deviations. Over the oceans, the coupled models with larger interannual standard deviations of annual mean SAT tend to simulate larger interannual standard deviations of both annual and semiannual SAT harmonics amplitudes. Most model errors are located in the belts 60°–70°N and 60°–70°S and over Antarctica. These errors are larger for those coupled models which do not employ dynamical modules for sea ice. No systematic differences are found in the simulated time averaged fields of the surface air temperature annual cycle characteristics for atmospheric models on one hand and for the coupled models on the other. But the coupled models generally simulate interannual variability of SAT AC APC better than the atmospheric models (which tend to underestimate it). For the coupled models, the results are not very sensitive to the choice of the particular scenario of anthropogenic forcing. There is a strong linear positive relationship between the model simulated time averaged semiannual SAT harmonics amplitude and interannual standard deviation of annual mean SAT. It is stronger over the tropical oceans and is weaker in the extratropics. In the tropical oceanic areas, it is stronger f

关键词： annual cycle reanalysis data climate model intercomparison

Agglomeration of coal and polyethylene mixtures during fixed‑bed co‑gasification

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International Journal of Coal Science & Technology 2024年第2期11卷 91-100页

作者： igor G.Donskoy Aleksandr N.Kozlov Maksim v.Penzik Denis A.Svishchev Lu Ding Melentiev Energy Systems Institute Russian Federation130 Lermontova StreetIrkutskRussia 664033 East China University of Science and Technology 130 Meilong RoadShanghai 200237China

The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory *** work aims to study the agglomeration process during the heating and oxidation of the *** measurement results(gas composition,pressure drop)provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel *** have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates,in which the molten polymer acts as a *** form as a result of interfacial interactions between components and filtration flow *** hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11,indicating the formation of stable hydrocarbon compounds on the carbon *** conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene.

关键词： Coal Polyethylene Gasification Combustion Agglomeration

Autoimmunity in acute ischemic stroke and the role of bloodbrain barrier: the dark side or the light one?

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Frontiers of Medicine 2019年第4期13卷 420-426页

作者： Nikolay v. Tsygan Alexandr P. Trashkov igor v. Litvinenko viktoriya A. Yakovleva Alexandr v. Ryabtsev Andrey G. vasiliev Leonid P. Churilov Department of Molecular and Radiation Biophysics B.P. Konstantinov Petersburg Nuclear Physics Institute Gatchina Leningrad Region 188300 Russian Federation Department of Nervous Diseases S.M. Kirov Military Medical Academy Saint Petersburg 194044 Russian Federation Department of Experimental Pharmacology I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry Saint Petersburg 194223 Russian Federation Department of Pathological Physiology with the Course of Immunopathology Saint Petersburg State Pediatric Medical University Saint Petersburg Russian Federation Department of Pathology Laboratory of the Mosaic of Autoimmunity Saint Petersburg State University Saint Petersburg 199034 Russian Federation

This article presents a synopsis of the current data on the mechanisms of blood-brain barrier (BBB) alteration and autoimmune response in acute ischemic stroke. Most researchers confirm the relationship between the severity of immunobiochemical changes and clinical outcome of acute ischemic stroke. Ischemic stroke is accompanied by aseptic inflammation, which alters the brain tissue and exposes the co-stimulatory molecules of the immune system and the neuronal antigens. To date, BBB is not considered the border between the immune system and central nervous system, and the local immune subsystems are found within and behind the BBB. BBB disruption contributes to the leakage of brain autoantigens and induction of secondary autoimmune response to neuronal antigens and long-term inflammation. Glymphatic system function is altered and jeopardized both in hemorrhagic and ischemic stroke types. The receptors of innate immunity (toll-like receptor-2 and toll-like receptor-4) are also involved in acute ischemia-reperfusion injury. Immune response is related to the key processes of blood clotting and fibrinolysis. At the same time, the stroke-induced immune activation may promote reparation phenomena in the brain. Subsequent research on the reduction of the acute ischemic brain injury through the target regulation of the immune response is promising.

关键词： stroke blood-brain barrier autoimmunity innate immunity inflammation cell death

Fe Nanoclusters on the Ge（001） Surface Studied by Scanning Tunneling Microscopy, Density Functional Theory Calculations and X-Ray Magnetic Circular Dichroism

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Nano Research 2011年第10期4卷 971-978页

作者： Olaf LUbben Sergey A. Krasnikov Alexei B. Preobrajenski Barry E. Murphy igor v. Shvets Centre for Research on Adaptive Nanostructures and Nanodevices （CRANN） School of Physics Trinity College Dublin Dublin 2 Ireland MAX-lab Lund University Box 118. 22100 Lund Sweden

The growth of Fe nanoclusters oN the Ge（001） surface has been studied using low-temperature scanning tunneling microscopy （STM） and density functional theory （DFT） calculations. STM results indicate that Fe nucleates on the Ge（001） surface, forming well-ordered nanoclusters of uniform size. Depending on the preparation conditions, two types of nanoclusters were observed having either four or sixteen Fe atoms within a nanocluster. The results were confirmed by DFT calculations. Annealing the nanoclusters at 420 K leads to the formation of nanorow structures, due to cluster mobility at such temperature. The Fe nanoclusters and nanorow structures formed on the Ge（001） surface show a superparamagnetic behaviour as measured by X-ray magnetic circular dichroism.

关键词： Ge(001) iron nanoclusters self-assembly scanning tunnelling microscopy X-ray magnetic circular dichroism density functional theory calculations

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

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 conservation *** strategy is based on the Galilean invariance of dynamic equations and optimization of the reference frame,in which the equations are numerically *** optimal reference frame moves(locally in time)with the average 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 evolving 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 volume methods Galilean invariance

Extended Corey-Chaykovsky 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.Ivanova 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 divergent synthesis of benzannulated 2,8-dioxabicyclo[3.2.1]octanes and 2,3-dihydrobenzofurans using the concept of extended Corey-Chaykovsky *** this concept,2-hydroxychalcones were treated with the Corey ylide providing highly reactive 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.vakhitov 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 Zavoisky 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 extensively 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 provide the films with magnetic properties spanning from very soft ferromagnet for memory applications to intermediately soft and moderately hard for the programmable logic and circuit biasing, respectively. 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

Synergistic Co-doping effect of CNTs and PvP in Na_(4)MnCr(PO_(4))3 cathode as a strategy for improving the electrochemical performance of SIBs

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Chinese Chemical Letters 2024年第2期35卷 539-543页

作者： Ruoyu Chen Denys S.Butenko Shilin Li Xinyu Zhang Guangshe Li igor v.Zatovsky Wei Han College of Physics State Key Laboratory of Inorganic Synthesis and Preparative ChemistryInternational Center of Future ScienceJilin UniversityChangchun 130012China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China F.D.Ovcharenko Institute of Biocolloidal Chemistry NAS UkraineKyiv 03142Ukraine

In order to solve the contradiction between the rapidly growing energy demand and the excessive exploitation of fossil fuels,it is urgent to research and develops more environmentally friendly and efficient energy storage ***,the development of high-performance cathode materials to enhance the energy density of SIB is currently one of the most important topics of scientific *** high-voltage and low-cost cathode material for SIBs,a composite of carbon-coated Na_(4)MnCr(PO_(4))_(3)(NASICON-type),polyvinylpyrrolidone(PvP),and modified carbon nanotubes(CNTs)is prepared by sol-gel and freeze-drying *** to the high conductivity of CNTs,the conductivity of the composite is significantly improved,and its initial capacity is increased to 114 mAh/g at 0.5 C and 96 mAh/g at 5 C(Mn^(2+)/Mn^(4+)conversion for voltage windows 1.4-4.3 v).Moreover,the multi-electrons transfer of Cr^(3+)/Cr^(4+) and Mn^(2+)/Mn^(4+) can provide a high capacity of 165 mAh/g at 0.1 C and 102 mAh/g at 5 C in the high voltage window of 1.4-4.6 ***,PvP can effectively inhibit the Jahn-Teller effect caused by Mn ion,making the composite have more excellent high-rate performance and *** addition,GITT,EIS and Cv curves were drawn to better reveal the excellent kinetic properties of Na_(4)MnCr(PO_(4))_(3)@C@PvP@CNT cathode,and the mechanism of its performance improvement is deeply studied and ***,the co-doping of CNTs and PvP is a simple way to high conductivity and fast charging of cathode materials for SIBs.

关键词： Sodium-ion batteries Na_(4)MnCr(PO_(4))_(3) Carbon nanotubes Polyvinylpyrrolidone Synergistic effect