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Plasma Science and Technology 2015年第1期17卷 64-70页

作者：刘美琴李博轮刘纯亮 Fuks mikhail Edl SCHAMILOGLU Key Laboratory of Physical Electronics and Devices of the Ministry of Education Xi'an Jiaotong University Department of Electrical and Computer Engineering University of New Mexico

Prticle-in-cell（PIC） simulations demonstrated that,when the relativistic magnetron with diffraction output（MDO） is applied with a 410 kV voltage pulse,or when the relativistic magnetron with radial output is applied with a 350 kV voltage pulse,electrons emitted from the cathode with high energy will strike the anode block *** emitted secondary electrons and backscattered electrons affect the interaction between electrons and RF fields induced by the operating modes,which decreases the output power in the radial output relativistic magnetron by about 15%（10%for the axial output relativistic magnetron）,decreases the anode current by about 5%（5%for the axial output relativistic magnetron）,and leads to a decrease of electronic efficiency by 8%（6%for the axial output relativistic magnetron）.The peak value of the current formed by secondary and backscattered current equals nearly half of the amplitude of the anode current,which may help the growth of parasitic modes when the applied magnetic field is near the critical magnetic field separating neighboring ***,mode competition becomes more serious.

关键词： secondary electron and backscattered electron emission relativistic magnetron mode competition critical magnetic field output power anode current electronic efficiency transparent cathode solid cathode

A localized Fourier collocation method for 2D and 3D elliptic partial differential equations:Theory and MATLAB code

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International Journal of Mechanical System Dynamics 2022年第4期2卷 339-351页

作者： Yan Gu Zhuojia Fu mikhail V.Golub Department of Computational Mathematics School of Mathematics and StatisticsQingdao UniversityQingdaoChina Department of Engineering Mechanics College of Mechanics and MaterialsHohai UniversityNanjingChina Department of Applied Mathematics Institute for MathematicsMechanics and InformaticsKuban State UniversityKrasnodarRussian Federation

A localized Fourier collocation method is proposed for solving certain types of elliptic boundary value *** method first discretizes the entire domain into a set of overlapping small subdomains,and then in each of the subdomains,the unknown functions and their derivatives are approximated using the pseudo-spectral Fourier collocation *** key idea of the present method is to combine the merits of the quick convergence of the pseudo-spectral method and the high sparsity of the localized discretization technique to yield a new framework that may be suitable for large-scale *** present method can be viewed as a competitive alternative for solving numerically large-scale boundary value problems with complex-shape *** numerical experiments involving Poisson,Helmholtz,and modified-Helmholtz equations in both two and three dimensions are presented to demonstrate the accuracy and efficiency of the proposed method.

关键词： meshless method collocation method Fourier basis functions large-scale problem

Reduction of friction by normal oscillations.Ⅱ.In-plane system dynamics

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Friction 2017年第2期5卷 534-535,536页

作者： Xinyu MAO Valentin L.POPOV Jasminka STARCEVIC mikhail POPOV Technische Universit(a)t Berlin Berlin 10623 GermanyTsinghua University Beijing 100084 China Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk State University Tomsk 634050 Russia

The influence of out-of-plane oscillations on friction is a well-known phenomenon that has been studied extensively with various experimental methods,e.g.,pin-on-disk ***,existing theoretical models have yet achieved only qualitative correspondence with *** we argue that this may be due to the system dynamics (mass and tangential stiffness) of the pin or other system components being *** paper builds on the results of a previous study [19] by taking the stiffness and resulting dynamics of the system into *** main governing parameters determining macroscopic friction,including a dimensionless oscillation amplitude,a dimensionless sliding velocity and the relation between three characteristic frequencies (that of externally excited oscillation and two natural oscillation frequencies associated with the contact stiffness and the system stiffness) are *** the limiting cases of a very soft system and a very stiff system,our results reproduce the results of previous *** between these two limiting cases there is also a resonant case,which is studied here for the first *** resonant case is notable in that it lacks a critical sliding velocity,above which oscillations no longer reduce *** obtained for the resonant case are qualitatively supported by experiments.

关键词： sliding friction out-of-plane oscillation stiffness system dynamics macroscopic friction coefficient

Positivity-Preserving Runge-Kutta Discontinuous Galerkin Method on Adaptive Cartesian Grid for Strong Moving Shock

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Numerical Mathematics(Theory,Methods and Applications) 2016年第1期9卷 87-110页

作者： Jianming Liu Jianxian Qiu mikhail Goman Xinkai Li Meilin Liu School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China Faculty of Technology De Montfort UniversityLeicester LE19BHEngland School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computation Xiamen UniversityXiamen 361005China Shanghai Institute of Satellite Engineering Shanghai 200240China

In order to suppress the failure of preserving positivity of density or pres-sure,a positivity-preserving limiter technique coupled with h-adaptive Runge-Kutta discontinuous Galerkin(RKDG)method is developed in this *** a method is implemented to simulate flows with the large Mach number,strong shock/obstacle interactions and shock *** Cartesian grid with ghost cell immersed boundary method for arbitrarily complex geometries is also *** ap-proach directly uses the cell solution polynomial of DG finite element space as the interpolation *** method is validated by the well documented test ex-amples involving unsteady compressible flows through complex bodies over a large Mach *** numerical results demonstrate the robustness and the versatility of the proposed approach.

关键词： Discontinuous Galerkin method adaptive Cartesian grid positivity-preserving im-mersed boundary method complex geometry

The Objective Assessment of Event-Related Potentials:An Influence of Chronic Pain on ERP Parameters

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Neuroscience Bulletin 2023年第7期39卷 1105-1116页

作者： Maksim Zhuravlev mikhail Novikov Ruzanna Parsamyan Anton Selskii Anastasiya Runnova Coordinating Center for Fundamental Research National Medical Research Center for Therapy and Preventive MedicineMoscow 101000Russia Institute of Physics Saratov State UniversitySaratov 410012Russia Department of Fundamental Research in Neurocardiology Institute of Cardiological ResearchSaratov State Medical UniversitySaratov 410012Russia

The article presents an original method for the automatic assessment of the quality of event-related potentials(ERPs),based on the calculation of the coefficientε,which describes the compliance of recorded ERPs with some statistically significant *** method was used to analyze the neuropsychological EEG monitoring of patients suffering from *** frequency of migraine attacks was correlated with the spatial distribution of the coefficientsε,calculated for EEG *** than 15 migraine attacks per month was accompanied by an increase in calculated values in the occipital *** with infrequent migraines exhibited maximum quality in the frontal *** automatic analysis of spatial maps of the coefficientεdemonstrated a statistically significant difference between the two analyzed groups with different means of migraine attack numbers per month.

关键词： Event-related potential Chronic migraine ERP quality Automatic evaluation

Polyhydroxybutyrate/Hydroxyapatite Highly Porous Scaffold for Small Bone Defects Replacement in the Nonload-bearing Parts

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Journal of Bionic Engineering 2017年第4期14卷 648-658页

作者： Fedor Senatov Natalia Anisimova mikhail Kiselevskiy Aleksey Kopylov Viktor Tcherdyntsev Aleksey Maksimkin National University of Science and Technology MISIS Leninskiy pr. 4 Moscow 119049 Russian Federation N.N. Blokhin Russian Cancer Research Center Kashirskoye sh. 23 Moscow 115478 Russian Federation

In the present work, Polyhydroxybutyrate （PHB）/Hydroxyapatite （HA） porous composites （10%, 20%, 30 %, 40%, 50% weight HA） were obtained by sintering. PHB/20% HA optimally combines satisfactory mechanical properties with a high content of the bioactive component （HA）. Porous PHB/20% HA scaffolds have shown high mechanical properties （compressive strength of 106 MPa and Young＇s modulus of 901 MPa）. A high volume fraction of interconnected pores （〉 50 vol.%） was achieved with pore size of 50 grn - 500 gm. Biocompatibility of porous pure PHB and PHB/20%HA, as its osseointegration were assessed in vitro and after implantation in laboratory animals. PHB/20% HA （-5% ＋ 0.9%） and pure PHB ~3% ~ 1.4%） samples after 24 hours of incubation with human leucocytes showed no significant level of cytotoxicity when p = 0.648 （p-value）. In vitro massive adhesion of mouse Multipotent Mesenchymal Stromal Cells （MMSC） to the surface of both porous samples was shown. PHB/20% HA induced more intensive MMSC proliferation compared to pure PHB, which are 31% ＋ 6.1% and 20% ＋ 5.7 % respectively when p = 0.039. We observed the resorption （implant surface area was reduced by 49 %） and integration of the porous PHB/20% HA samples into surrounding tissues after 30 days of implantation. The signs of osteoclasts accumulation, neo-angigenesis and new bone formation were observed, which make PHB/20% HA promising for bone tissue engineering.

关键词： polyhydroxybutyrate hydroxyapatite scaffold porous structure implant bone regeneration

Wolf phase tomography(WPT) of transparent structures using partially coherent illumination

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Light(Science & Applications) 2020年第1期9卷 656-664页

作者： Xi Chen mikhail E.Kandel Chenfei Hu Young Jae Lee Gabriel Popescu Quantitative Light Imaging Laboratory Beckman Institute for Advanced Science and TechnologyDepartment of Electrical and Computer EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA

In 1969,Emil Wolf proposed diffraction tomography using coherent holographic imaging to extract 3D information from transparent,inhomogeneous *** the same era,the Wolf equations were first used to describe the propagation correlations associated with partially coherent *** these two concepts,we present Wolf phase tomography(WPT),which is a method for performing diffraction tomography using partially coherent *** reconstruction works directly in the space-time domain,without the need for Fourier transformation,and decouples the refractive index(RI)distribution from the thickness of the *** demonstrate the WPT principle using the data acquired by a quantitative-phase-imaging method that upgrades an existing phase-contrast microscope by introducing controlled phase shifts between the incident and scattered *** illumination field in WPT is partially spatially coherent(emerging from a ring-shaped pupil function)and of low temporal coherence(white light),and as such,it is well suited for the Wolf *** three intensity measurements corresponding to different phase-contrast frames,the 3D RI distribution is obtained immediately by computing the Laplacian and second time derivative of the measured complex correlation *** validate WPT with measurements of standard samples(microbeads),spermatozoa,and live neural *** high throughput and simplicity of this method enables the study of 3D,dynamic events in living cells across the entire multiwell plate,with an RI sensitivity on the order of 10^(−5).

关键词： WPT coherent illumination

Structure,mechanical characteristics,biodegradation,and in vitro cytotoxicity of magnesium alloy ZX11 processed by rotary swaging

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Journal of Magnesium and Alloys 2020年第4期8卷 1038-1046页

作者： Natalia Martynenko Natalia Anisimova mikhail Kiselevskiy Natalia Tabachkova Diana Temralieva Dmitry Prosvirninb Vladimir Terentiev Andrey Koltygina Vladimir Belov mikhail Morosov Vladimir Yusupov Sergey Dobatkina National University of Science and Technology"M1SIS" Leninsky prospect4119049 MoscowRussia A.A.Baikov Institute of Metallurgy and Materials Science of the RAS Leninsky prospect49119334 MoscowRussia ≪N.N.Blokhin National Medical Research Center of Oncology≫of the Ministry of Health of the Russian Federation Kashirskoye Highway23115478 MoscowRussia A.M.Prokhorov General Physics Institute of the RAS Vavilova st.3&Moscow 119991、Russia 5.Department of Materials Science and EngineeringMonash UniversityClaytonMelbourne VIC 3800Australia 6.Department of Mechanical EngineeringThe University of Western AustraliaCrawleyPerth WA 6009Australia

Rotary swaging(RS)of alloy Mg-1.03Zn-0.66Ca(ZX11)was shown to refine the average grain size to 4.5±1.2μm in a longitudinal section and 4.8±0.9μm in a transverse *** addition,a small amount of Mg2Ca particles about 300nm in size and Mg6Zn3Ca2 particles with a size of about lOOnm was *** resulted in pronounced strengthening:the yield strength and the ultimate tensile strength rose to 210±8 MPa and 276±6 MPa,respectively,while the elongation hardly decreased(22.0±1.8% and 18.3±2.9% before and after RS).Furthermore,RS led to an increase in the fatigue limit of the alloy from 120 MPa to 135 MPa and did not impair its resistance to chemical *** studies in vitro showed that ZX11 induces hemolysis without inhibiting the viability of peripheral blood mononuclear cells and has a more pronounced cytotoxic effect on tumor cells in comparison with non-transformed *** significant difference of the latter effect between the initial and the deformed states was observed.

关键词： Magnesium alloy Rotary swaging Mechanical characteristics Hemolysis Cell viability Cytotoxicity

Natural convective heat transfer and nanofluid flow in a cavity with top wavywall and corner heater

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Journal of Hydrodynamics 2016年第5期28卷 873-885页

作者： mikhail A. SHEREMET Ioan POP Hakan F. OZTOP Nidal ABU-HAMDEH Department of Theoretical Mechanics Tomsk State University Tomsk Russia Department of Nuclear and Thermal Power Plants Tomsk Polytechnic University Tomsk Russia Department of Applied Mathematics BabesBolyai University Cluj-Napoca Romania Department of Mechanical Engineering Technology Faculty Flrat University Elazig Turkey Mechanical Engineering Department Faculty of Engineering King Abdulaziz University Jeddah Saudi Arabia

A numerical analysis of natural convection of nanofluid in a wavy-walled enclosure with an isothermal comer heater has been carried out. The cavity is heated from the left bottom comer and cooled from the top wavy wall while the rest walls are adiaba- tic. Mathematical model has been formulated using the single-phase nanofluid approach. Main efforts have been focused on the effects of the dimensionless time, Rayleigh number, undulation number, nanoparticle volume fraction and length of comer heaters on the fluid flow and heat transfer inside the cavity. Numerical results have been presented in the form of streamlines, isotherms, velocity and temperature profiles, local and average Nusselt numbers. It has been found that nanoparticle volume fraction essentially affects both fluid flow and heat transfer while undulation number changes significantly only the heat transfer rate.

关键词： wavy cavity natural convection nanofluid comer heater numerical results

Enhanced oil recovery by low-salinity water spontaneous imbibition (LSW-SI) in a typical tight sandstone formation of mahu sag from core scale to field scale

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Petroleum 2021年第3期7卷 272-281页

作者： Bing Wei Lele Wang Tao Song Mengying Zhong mikhail A.Varfolomeev State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500China Department of Petroleum Engineering Kazan Federal UniversityKremlevskaya Str.18Kazan420008Russia

Accelerating mass exchange between matrix and fractures is the essence of enhanced oil recovery(EOR)in tight formations after natural *** salinity water(LSW)injection has been commerciallyproven in conventional reservoirs EOR,with scale projects in progress *** is,however,a lack of understanding of the EOR effect in tight ***,in this work,we introduced LSWEOR to a target tight formation using huff-puff *** imbibition(SI)tests were firstly performed on homogenous Berea sandstone cores with decreasing salinity brine to observe the production *** results indicated that the oil recovery of the tight rock was boosted by tuning brine *** all the used brines with salinity ranging from 0.021%to 2.1%TDS(total dissolved salinity),the 0.21%TDS brine showed a rapid increase in oil production over imbibing time,which finally led to an incremental oil recovery of 4.5%OOIP(original oil in place).Core-scale modeling was conducted by history-matching the oil recovery dynamics of the SI results through modifying capillary pressure and relative permeability.A full-scale reservoir model was constructed using micro-seismic data to model fracture geometry combing fracturing results and scaling parameters obtained from core scale *** is proven that LSW huff-n-puff stimulated the oil production after natural depletion and improved MEE(mass exchange efficiency)of the target formation,but the EOR benefit was not comparable to CO2 and surfactant-assisted water huff-puff methods.

关键词： Fractured tight formation Enhanced oil recovery Low-salinity effect Spontaneous imbibition Huff-n-puff