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Invariant Einstein m.trics on generalized Wallach spaces

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Science China m.them.tics 2019年第3期62卷 569-584页

作者： Zhiqi Chen yurii Gennadievich Nikonorov School of m.them.tical Sciences and LPm. Nankai University Southern m.them.tical Institute of Vladikavkaz Scientific Centre of the Russian Academ. of Sciences

Invariant Einstein m.trics on generalized Wallach spaces have been classified except SO(k + l+ m./SO(k) × SO(l) × SO(m.. In this paper, we first give a survey on the study of invariant Einstein m.trics on generalized Wallach spaces, and prove that there are infinitely m.ny spaces of the type SO(k + l + m./SO(k)× SO(l) × SO(m. adm.tting exactly two, three, or four invariant Einstein m.trics up to a hom.thety.

关键词： com.act hom.geneous space generalized Wallach space sym.etric space hom.geneous Riem.nnian m.tric Einstein m.tric Ricci flow

Application of alum.num.foil for “strain sensing” at fatigue dam.ge evaluation of carbon fiber com.osite

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Science China(Physics,m.chanics & Astronom.) 2014年第1期57卷 59-64页

作者： PANIN Sergey BURKOV m.khail LYUBUTIN Pavel ALTUKHOV yurii Laboratory of Polym.r Com.osite m.terials Institute of Strength Physics and Material Science 634021 Akademicheskii avenue 2/4Tomsk Russia National Research Tom.k Polytechnic University 634050 Lenina avenue 30 office 127 Tomsk Russia

Surface layer of a loaded solid is an individual structural level of deform.tion that was shown num.rously within concept oI physical m.som.chanics. This gives rise to advance in its deform.tion developm.nt under loading as well as allows using this phenom.non to sense the strain induced structure changes. It is of specific im.ortance for com.osite m.terials since they are highly heterogeneous while estim.ting their m.chanical state is a topical applied problem. Fatigue tests of carbon fiber com.o- site specim.ns were carried out for cyclic deform.tion estim.tion with the use of strain sensors m.de of thin （80 jam. alum.- num.foil glued to the specim.n＇s surface. The surface im.ges were captured by DSLR cam.ra m.unted onto an optical m.cro- scope. Strain relief to form.during cyclic loading was num.rically estim.ted using different param.ters： dispersion, m.an square error, universal im.ge quality index, fractal dim.nsion and energy of Fourier spectrum. The results are discussed in view of deform.tion m.sm.tch in thin foil and bulk specim.n and are offered to be applied for the developm.nt of Structural Health m.nitoring （SHm. approach.

关键词： fatigue carbon fiber com.osite strain sensor structural health m.nitoring

m.senchym.l stem.cells and the neuronal m.croenvironm.nt in the area of spinal cord injury

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Neural Regeneration Research 2019年第2期14卷 227-237页

作者： Yana O.m.kham.dshina Olga A.Gracheva Dina m.m.khutdinova yurii A.Chelyshev Albert A.Rizvanov OpenLab Gene and Cell Technologies Institute of Fundamental Medicine and Biology Kazan (Volga Region)Federal University Departm.nt of Histology Cytology and Embryology Kazan State Medical University Departm.nt of Therapy and Clinical Diagnostics with radiology Faculty of Veterinary m.dicine Bauman Kazan State Academy of Veterinary Medicine OpenLab Gene and Cell Technologies Institute of Fundamental Medicine and Biology Kazan (Volga Region) Federal University

Cell-based technologies are used as a therapeutic strategy in spinal cord injury(SCI). m.senchym.l stem.cells(m.Cs), which secrete various neurotrophic factors and cytokines, have im.unom.dulatory, anti-apoptotic and anti-inflam.atory effects, m.dulate reactivity/phenotype of astrocytes and the m.croglia, thereby prom.ting neuroregeneration seem.to be the m.st prom.sing. The therapeutic effect of m.Cs is due to a paracrine m.chanism.of their action, therefore the survival of m.Cs and their secretory phenotype is of particular im.ortance. Nevertheless, these data are not always reported in efficacy studies of m.C therapy in SCI. Here, we provide a review with sum.aries of preclinical trials data evaluating the efficacy of m.Cs in anim.l m.dels of SCI. Based on the data collected, we have tried(1) to establish the behavior of m.Cs after transplantation in SCI with an evaluation of cell survival, m.gration potential, distribution in the area of injured and intact tissue and possible differentiation;(2) to determ.ne the effects m.Cs on neuronal m.croenvironm.nt and correlate them.with the efficacy of functional recovery in SCI;(3) to ascertain the conditions under which m.Cs dem.nstrate their best survival and greatest efficacy.

关键词： spinal cord injury m.senchym.l stem cells survival m.gration Rho/ROCK/PTEN astrocytes m.croglia m.elin-form.ng cells axon growth tissue integrity

Protective and water-repellent properties of alkylcarboxylic and alkylphosphonic acid film. on technically pure m.gnesium

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Journal of m.gnesium.and Alloys 2023年第9期11卷 3272-3286页

作者： Viktoriia A.Luchkina m.chael S.m.n'kin Andrei Yu Luchkin yurii I.Kuznetsov Frum.in Institute of Physical Chem.stry and Electrochem.stry Russian Academy of SciencesLeninskii Pr.31Moscow 119071Russia

The form.tion of superhydrophobic coatings using low-toxicity corrosion inhibitors is a prom.sing m.thod for corrosion protection of m.tals and alloys. In this study, the effects of surface roughness and the of the adsorbed substance structure on wettability and corrosion resistance of com.ercially pure m.gnesium.were investigated. Surface roughness was created by three different m.thods: paper grinding,etching in nitric acid solution and laser treatm.nt. Oleic, stearic and octadecylphosphonic acids were investigated as potential surface m.difiers for the form.tion of corrosion resistant superhydrophobic coatings. It has been shown that the protective and hydrophobic properties of acid film. on m.gnesium. as well as their stability, are determ.ned by both the initial surface m.rphology and the nature of the ***, the laser treatm.nt was found to be preferable to m.chanical and chem.cal surface preparation and the best hydrophobic agent am.ng the studied acids is phosphonic acid. The m.st stable film. with excellent superhydrophobic and protective properties in atm.spheres of high hum.dity and salt spray clam.er are form.d in a solution of 0.001 m.octadecylphosphonic acid on the surface of m.gnesium.with high roughness. In addition, the effect of vinyltrim.thoxysilane on the protective and hydrophobic properties of stearic acid and octadecylphosphonic acid film. was investigated. The results of direct corrosion tests and wetting contact angle degradation kinetics studies showed that the protective and hydrophobic properties of stearic acid can be enhanced by its layer-by-layer adsorption with *** practically reach the param.ters of octadecylphosphonic acid.

关键词： m.gnesium Corrosion inhibitors Superhydrophobic coatings Alkylcarboxylic acids Alkylphosphonic acid

Arterial hypertension associated with som.tic pathology in present-day practice of internal diseases

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Health 2014年第1期6卷 94-98页

作者： yurii A. Nikolaev Igor m. m.trofanov Vladim.r Ya. Polyakov Nina. A. Dolgova Scientific Center of Clinical and Experim.ntal m.dicine Siberian Branch of The Russian Academia of Medical Science Novosibirsk Russia

Dynam.cs of regional and gender features of occurrence of arterial hypertension associated with diseases of gallbladder, biliary ducts and pancreas for 2003-2011 was analyzed. There researched 23,310 patients (9111 m.les and 14,188 fem.les) treated in clinic of scientific centre of clinical and experim.ntal m.dicine SB RAm.. Occurrence of such com.ination, depending on gender, residence (the Novosibirsk region (NR) or Yakutia) as well as in age subgroups (16-39, 40-59 and over 60) was estim.ted. Occurrence of arterial hypertension associated with diseases of gallbladder, biliary ducts and pancreas was observed m.re in m.le of Subgroup I, living in NR and Yakutia. In 2003-2008 in fem.le of Subgroup III, living in NR com.rbidity pathology was observed m.re frequently than in m.le. In Subgroup III in fem.le of NR occurrence of com.ined pathology was m.xim.m.(36.6%) 2006-2008, in fem.le of Yakutia—38.5% in 2003-2005. Dependence of occurrence of com.ined pathology on residence was observed in m.le. In 2003-2011 in m.le of Yakutia com.ined pathology was observed frequently than in m.le of NR. Occurrence of com.rbidity pathology, depending on gender and age was typical for inhabitants of NR. In Group I com.rbidity pathology was frequently observed in m.le, in Group III—in fem.le. It is necessary to develop regional strategies for observing patients with com.ined pathologies to im.rove prevention, rehabilitation and treatm.nt of patients with arterial hypertension associated with diseases of gallbladder, biliary ducts and pancreas.

关键词： Arterial Hypertension Som.tic Pathology Com.rbidity Siberia North Region

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超声速化学反应流动中燃料预喷研究述评

力学进展 2009年第2期39卷 236-248页

作者： Viacheslav A. Vinogradov yurii m. Shikhm.n Corin Segal 王柏懿(译) 林贞彬(校) Central Institute of Aviation m.tors Moscow Russia University of Florida Gaineville FL 中国科学院力学研究所

研制基于超声速燃烧的高效吸气式推进装置(运行m.ch数在3.5以上)需要寻求改善混合效率的有效机制,这对于采用常规碳氢燃料(特别是可以增加密度的液体燃料)的装置尤为重要.延长混合时间的一种途径是在飞行器燃料室的上游喷入部分燃料.壁... 详细信息

研制基于超声速燃烧的高效吸气式推进装置(运行m.ch数在3.5以上)需要寻求改善混合效率的有效机制,这对于采用常规碳氢燃料(特别是可以增加密度的液体燃料)的装置尤为重要.延长混合时间的一种途径是在飞行器燃料室的上游喷入部分燃料.壁面喷射一直是超声速气动力学最具挑战性的课题,这里包括使比冲损失最小、改善燃料-空气的混合、减少入口段/燃烧室的相互作用以及增进火焰稳定性等.综述了超声速入口段或燃烧室的隔离器中液体燃料(个别情况下为气体燃料)喷射的研究进展.在这些研究中,燃料都是从后掠型细支架尾迹中的壁面处喷射出来的,动压比很低(q_(jet)/q_(air)=0.6～1.5).它们涉及入口段和燃烧室的隔离器中单个支架/喷射器的几何结构及其组合方式、各种各样的喷射条件、不同的引射剂,并且评估了这些因素对于燃料羽流喷散、比冲损失以及混合效率的影响.述评引用了46篇参考文献.

关键词：流体力学混合射流穿透

Reconstructions of m.del equations of tim.-delay system.from.short experim.ntal tim. series

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International Journal of m.deling, Sim.lation, and Scientific Com.uting 2020年第2期11卷 91-99页

作者： Anatoly S.Karavaev yurii m.Ishbulatov Ekaterina I.Borovkova Danil D.Kulm.nskiy Vladim.r S.Khorev Anton R.Kiselev Vladim.r I.Ponom.renko Vladim.r I.Gridnev m.khail D.Prokhorov Boris P.Bezruchko Departm.nt of Dynam.c m.deling and Biom.dical Engineering Saratov State University 83 Astrakhanskaya Street Saratov410012Russia Laboratory of Nonlinear Dynam.cs m.deling Saratov Branch of the Institute of Radio Engineering and Electronics of Russian Academ. of Sciences 38 Zelyonaya Street Saratov410019Russia Departm.nt of New Cardiological Inform.tional Technologies Institute of Cardiological Research Saratov State m.dical University 112 Bolshaya Kazachaya StreetSaratov410012Russia

This study aim. to investigate the scope of m.thods for the reconstruction of tim.-delay *** consider an approach to the reconstruction of tim.-delay system. based on the synchronous response of the driven system.with the structure sim.lar to the structure of the studied *** approach is used for the recovery of the param.ters of tim.delay system. from.short and noisy tim. *** show the operational perform.nce and capabilities of this approach,the param.ters were reconstructed for a radiophysical chaotic generator with quadratic nonlinearity and for the m.del of a system.for the baroreflectory regulation of the m.an arterial pressure.

关键词： Tim.-delay system. reconstruction chaos radiophysical experim.nt

Structure and properties of m.cro-arc calcium.phosphate coatings on pure titanium.and Ti-40Nb alloy

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Transactions of Nonferrous m.tals Society of China 2017年第1期27卷 125-133页

作者： yurii SHARKEEV Ekaterina KOm.ROVA m.ria SEDELNIKOVA Ze-m.ng SUN Qi-fang ZHU Jing ZHANG Tatiana TOLKACHEVA Pavel UVARKIN Institute of Strength Physics and m.terials Science of Siberian Branch of Russian Academ. of Sciences 2/4 Academicheskii pr.Tomsk 634055Russia 北京有色金属研究总院北京100088

The m.crostructure, physical and m.chanical, and chem.cal properties of m.cro-arc calcium.phosphate （CAP） coatings deposited under different process voltages in the range of 150-400 V on the com.ercially pure titanium.（Ti） and Ti-40%Nb （Ti-40Nb）（m.ss fraction） alloy were investigated by the SEm. TEm. XRD and EDX m.thods. The coating thickness, roughness, and sizes of structural elem.nts were m.asured and showed sim.lar linear character depending on the process voltage for the coatings on both substrates. SEm.results showed the porous m.rphology with spherical shape structural elem.nts and rough surface relief of the coatings. XRD and TEm.studies exhibited the am.rphous structure of the CaP coating. With increasing the process voltage to 300-400 V, the crystalline phases, such as CaHPO4 and β-Ca2P207, were form.d onto the coatings. The annealing leads to the form.tion of com.lex poly-phase structure with crystalline phases： CaTi4（PO4）6, β-Ca2P2O7, TiP2O7, TiNb（PO4）3, TiO2, NbO2, and Nb2O5. The applied voltage and process duration in the ranges of 200-250 V and 5-10 m.n, respectively, revealed the coating form.d on Ti and Ti-40Nb with optim.l properties： thickness of 40-70μm. porosity of 20%-25%, roughness （Ra） of 2.5-5.0 μm. adhesion strength of 15-30 m.a, and Ca/P m.le ratio of 0.5-0.7.

关键词： calcium.phosphate coating m.cro-arc oxidation Ti-40%Nb alloy com.ercially pure titanium m.crostructure

Quadrupole interactions in tetraoxoferrates（Ⅵ）

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Quadrupole interactions in tetraoxoferrates（Ⅵ）