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Research in Astronomy and Astrophysics 2024年第1期24卷 44-50页

作者： evgeny Staritsin K.A.Barkhatova Kourovka Astronomical Observatory B.N.Yeltsin Ural Federal Universitypr.Lenina 51Ekaterinburg 620000Russia

This paper investigates the spin-up of a mass-accreting star in a close binary system passing through the first stage of mass exchange in the Hertzsprung gap. Inside an accreting star, angular momentum is carried by meridional circulation and shear turbulence. The circulation carries part of the angular momentum of the accreted layers to the accretor's surface. The greater the rate of arrival of angular momentum in the accretor is, the greater this part. It is assumed that this part of the angular momentum can be removed by the disk further from the accretor. If the angular momentum in the matter entering the accretor is more than half the Keplerian value, then the angular momentum obtained by the accretor during mass exchange stage does not depend on the rate of arrival of angular momentum. The accretor may have the characteristics of a Be-star immediately after the end of mass exchange.

关键词： (stars:)binaries(including multiple):close stars:emission-line Be stars:early-type stars:rotation

A critical review on solid-state welding of high entropy alloys-processing,microstructural characteristics and mechanical properties of joints

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Defence Technology（防务技术） 2024年第4期34卷 78-133页

作者： Tushar Sonar Mikhail Ivanov evgeny Trofimov Aleksandr Tingaev Ilsiya Suleymanova Department of Welding Engineering Institution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia Department of Materials Science Physical and Chemical Properties of MaterialsInstitution of Engineering and TechnologySouth Ural State University(National Research University)Chelyabinsk454080Russia

The high entropy alloys(HEAs)are the newly developed high-performance materials that have gained significant importance in defence,nuclear and aerospace sector due to their superior mechanical properties,heat resistance,high temperature strength and corrosion *** alloys are manufactured by the equal mixing or larger proportions of five or more alloying *** exhibit superior mechanical performance compared to traditional engineering alloys because of the extensive alloying composition and higher entropy of *** state welding(SSW)techniques such as friction stir welding(FSW),rotary friction welding(RFW),diffusion bonding(DB)and explosive welding(EW)have been efficiently deployed for improving the microstructural integrity and mechanical properties of welded HEA *** HEA interlayers revealed greater potential in supressing the formation of deleterious intermetallic phases and maximizing the mechanical properties of HEAs *** similar and dissimilar joining of HEAs has been manifested to be viable for HEA systems which further expands their industrial ***,the main objective of this review paper is to present a critical review of current state of research,challenges and opportunities and main directions in SSW of HEAs mainly CoCrFeNiMn and Al_xCoCrFeNi *** state of the art of problems,progress and future outlook in SSW of HEAs are critically reviewed by considering the formation of phases,microstructural evolution and mechanical properties of HEAs joints.

关键词： High entropy alloys Solid state welding Microstructure Mechanical properties

Three-Dimensional Convection in an Inclined Porous Layer Subjected to a Vertical Temperature gradient

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Fluid Dynamics & Materials Processing 2024年第9期20卷 1957-1970页

作者： Ivan Shubenkov Tatyana Lyubimova evgeny Sadilov Computational Fluid Dynamics Laboratory Institute of Continuous Media Mechanics UB RASPerm614068Russia Theoretical Physics Department Perm State UniversityPerm614990Russia

In this paper,we study the onset and development of three-dimensional convection in a tilted porous layer saturated with a *** layer is subjected to a gravitational field and a strictly vertical temperature ***,problems of thermal convection in tilted porous media saturated with a liquid are studied by assuming constant different temperatures at the boundaries of the layer,which prevent these systems from supporting conductive(non-convective)*** boundary conditions considered in the present work allow a conductive state and are representative of typical geological *** an earlier work,we carried out a linear stability analysis of the conductive *** was shown that at any layer tilt angles,the most dangerous type of disturbances are longitudinal ***,a non-zero velocity component exists in *** the present work,threedimensional non-linear convection regimes are *** original three-dimensional problem is reduced to two-dimensional one with an analytical expression for the velocity z-component v_(z)=v_(z)(x,y).It is shown that the critical Rayleigh number values obtained through numerical solutions of the obtained 2D problem by a finite difference method for different layer inclination angles,are in a good agreement with those predicted by the linear *** number of convective rolls realized in nonlinear calculations also fits the linear theory predictions for a given cavity *** carried out at low supercriticalities show that a direct bifurcation takes *** increasing supercriticality,no transitions to other convective regimes are *** situation studied in this problem can be observed in oil-bearing rock formations under the influence of a geothermal temperature gradient,where the ensuing fluid convection can affect the distribution of oil throughout the layer.

关键词： Thermal convection inclined layer porous media vertical temperature gradient

Liver-brain axis with alcohol:Role of fibroblast growth factor 21(FgF21)

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genes & Diseases 2024年第2期11卷 509-511页

作者： Ke Zhang Elena Blokhina evgeny Krupitsky Marina Vetrova Ti-Fei Yuan Hua Wang Shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghai 200030China Pavlov University Valdman Institute of PharmacologySt.Petersburg 197022Russia Bekhterev National Medical Research Center for Psychiatry and Neurology St.Petersburg 192019Russia Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu 226007China Department of Oncology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230032China

Fibroblast growth factor21(FgF21)is a hormone that can balance nutrient fluctuations,control metabolic processes,and maintain energy *** FgF21 is produced by a variety of cell types,including hepatocytes,adipocytes,bone cells,myocardial cells,and pancreas cells,and act on various effector tissues such as brain,adipose tissue,liver,heart,and skeletal muscle.1 The target that FgF21 interacts with is the cell-surface receptor composed of FgF receptors in complex with the single-pass transmembrane proteinβ-*** receptors are abundantly expressed,both in peripheral tissues and some regions of the CNS,such as the hypothalamus and amygdala and the locus coeruleus(LC).2 Physiologically,FgF21 can be induced by various metabolic stresses,including hunger,protein deficiency,monosaccharides,and alcohol,by acting onβ-Klotho receptor in corresponding tissues,ultimately exerting regulatory effects(Fig.1)

关键词： Klotho homeostasis alcohol

gravitational Waves Background, as Well as Some UFO, FRB and Supernova Flares, Are Due to Compressibility of the Spacetime (CoST)

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Journal of High Energy Physics, gravitation and Cosmology 2024年第1期10卷 67-70页

作者： evgeny A. Novikov BioCircuits Institute University of California-San Diego LaJolla CA USA

The recently observed gravitational wave background is explained in terms of the quantum modification of the general relativity (Qmoger). Some UFO, FRB and supernova flares also can be explained in terms of Qmoger.

关键词： gravitational Wave Background Quantum Modification of the general Relativity Compressibility of the Spacetime (CoST)

Selenga River human dispersal path in Initial Upper Paleolithic

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人类学学报 2024年第5期43卷 780-796页

作者： evgeny P RYBIN Arina M KHATSENOVICH Institute of Archaeology and Ethnography Siberian Branch of Russian Academy of ScienceNovosibirsk 630090Russian Federation

Here,we consider earlier Upper Paleolithic sites in the Selenga River Basin,the main fluvial input of Lake Baikal that flows through northern Mongolia and the southwestern Transbaikal region of *** industries from these sites can be attributed to the laminar Initial Upper Paleolithic(IUP)technocomplex,widespread in southern Siberia and Central *** industries appear in the Selenga Basin about 45 kaBP *** of regional typological variability and the transport of exotic raw materials over long distances indicate that these populations participated in developed exchange networks and employed high mobility targeting the acquisition of necessary raw *** site types are present:quarry-workshops in northern Mongolia and generalized activity settlements in the southwestern *** faunal data are limited,we interpret available information as indicating a specialization on hunting,focusing on migrating steppe game *** distribution of sites in the mid-altitudes and landscapes of the Selenga-Orkhon geographical region and the geomorphological homogeneity of this territory also supported interregional human moves during the IUP.

关键词： Central Asia Initial Upper Paleolithic migration raw material hunting

伯醇对镍基催化剂在转移氢化反应中的抑制作用研究

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Chinese Journal of Catalysis 2024年第3期58卷 168-179页

作者： Nikolay Nesterov Alexey Philippov Vera Pakharukova evgeny gerasimov Stanislav Yakushkin Oleg Martyanov 博列斯科夫催化研究所俄罗斯新西伯利亚

本文研究了在转移加氢条件下,不同类型醇作为氢供体对镍基催化剂在苯并呋喃加氢反应中的活性影响.结果表明,使用异丙醇作为氢供体时,苯并呋喃的加氢过程为底物先发生脱芳构化,然后再进行脱氧反应.然而,当使用伯醇如甲醇、乙醇和正丙醇... 详细信息

本文研究了在转移加氢条件下,不同类型醇作为氢供体对镍基催化剂在苯并呋喃加氢反应中的活性影响.结果表明,使用异丙醇作为氢供体时,苯并呋喃的加氢过程为底物先发生脱芳构化,然后再进行脱氧反应.然而,当使用伯醇如甲醇、乙醇和正丙醇作为氢供体时,会导致镍基催化剂的不可逆失活.针对这一现象,进一步研究了伯醇使镍基金属催化剂失活的机理.结果表明,在250°C条件下,催化剂与伯醇的相互作用会导致形成非活性的碳化物Ni_(3)C,并且镍金属颗粒在氧化铝载体表面会发生烧结和偏析.

关键词：苯并呋喃转移加氢超临界共沉淀 Ni催化剂醇

gOx@Fe_(3)O_(4)-HNTs微囊反应器的构筑及多酶级联催化性能

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高等学校化学学报 2024年第1期45卷 72-83页

作者：黄雨晴刘妍张宏丽林森孙仕勇 gOLUBEV evgeny 吕瑞 KOTOVA Olga KOTOVA Elena 西南科技大学环境与资源学院固体废物处理与资源化教育部重点实验室绵阳621010 西南科技大学非金属矿产地质及其开发利用四川省高等学校重点实验室绵阳621010 俄罗斯科学院乌拉尔分院科米科学中心地质研究所瑟克特夫卡尔167982俄罗斯圣彼得堡国立矿业大学圣彼得堡199106俄罗斯

细胞内或细胞间的微空间使得生物体内的各种酶促反应能够高效有序地进行.基于此,本文结合天然酶-纳米酶二者的优势,构筑了一种模拟体内酶促级联反应的微囊反应器.首先,以天然硅铝酸盐矿物埃洛石纳米管(HNTs)为载体,在其表面原位生成具... 详细信息

细胞内或细胞间的微空间使得生物体内的各种酶促反应能够高效有序地进行.基于此,本文结合天然酶-纳米酶二者的优势,构筑了一种模拟体内酶促级联反应的微囊反应器.首先,以天然硅铝酸盐矿物埃洛石纳米管(HNTs)为载体,在其表面原位生成具有类辣根过氧化物酶活性的四氧化三铁(Fe3O4);随后,将其作为囊壁材料封装天然葡萄糖氧化酶(gOx),构筑gOx@Fe3O4-HNTs微囊反应器.当向体系中加入葡萄糖时,微囊反应器内的gOx先将葡萄糖转化为葡萄糖酸和过氧化氢(H_(2)O_(2)),之后H_(2)O_(2)继续被囊壁中的Fe_(3)O_(4)催化转化为羟基自由基,触发底物3,3',5,5'-四甲基联苯胺(TMB)显色.其中,Fe_(3)O_(4)-HNTs作为囊壁材料不仅使囊内gOx免受外界环境干扰,还可与gOx构建级联催化反应体系,这种酶-纳米酶微囊化级联体系具有比天然酶系统更优异的催化性能和反应稳定性.此外,因磁性Fe_(3)O_(4)的参与,材料还具有可回收性和重复使用性.这种酶-纳米酶复合微囊反应器为模拟生物体内限域环境下的多酶反应体系提供了新方法,同时为后续生物分析与仿生催化领域的进一步研究奠定了基础.

关键词：纳米酶微囊反应器埃洛石纳米管葡萄糖氧化酶级联反应

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(WA-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(WAAM) 3-D printing High deposition rate