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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

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

Nanosecond mid-infrared pulse generation via modulated thermal emissivity

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Light(Science & Applications) 2019年第1期8卷 724-731页

作者： Yuzhe Xiao Nicholas A.Charipar Jad Salman Alberto Pique mikhail A.Kats Department of Electrical and Computer Engineering University of Wisconsin-MadisonMadisonWI 53706USA Naval Research Laboratory 4555 Overlook Ave.SWWashingtonDC 20375USA Department of materials Science and Engineering University of Wisconsin-MadisonMadisonWI 53706USA Department of Physics University of Wisconsin-MadisonMadisonWI 53706USA

We demonstrate the generation of nanosecond mid-infrared pulses via fast modulation of thermal emissivity enabled by the absorption of visible pump pulses in unpatterned silicon and gallium *** free-carrier dynamics in these materials result in nanosecond-scale modulation of thermal emissivity,which leads to nanosecond pulsed thermal *** our knowledge,the nanosecond thermal-emissivity modulation in this work is three orders of magnitude faster than what has been previously *** also indirectly observed subnanosecond thermal pulses from hot carriers in *** experiments are well described by our multiphysics *** method of converting visible pulses into the mid infrared using modulated emissivity obeys different scaling laws and can have significant wavelength tunability compared to approaches based on conventional nonlinearities.

关键词： pump emissivity thermal

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

Two decades of fire activity over the PEEX domain:a look from space,with contribution from models and ground-based measurements

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Big Earth Data 2024年第2期8卷 350-396页

作者： Larisa Sogacheva Timo H.Virtanen Anu-maija Sundström Pekka Kolmonen mikhail Sofiev Hanna K.Lappalainen Antti Arola Finnish meteorological Institute Climate Research ProgrammeHelsinkiFinland Finnish meteorological Institute Space and Earth Observation CentreHelsinkiFinland Institute for Atmospheric and Earth System Research/Physics Faculty of ScienceUniversity of HelsinkiHelsinkiFinland

It has been suggested that forest fires will become more frequent/intense with changing climate,which would increase aerosol/gas emissions into the atmosphere.A better under-standing of the relations between meteorological conditions,fires,and fire emissions will help estimate the climate response via forest *** this study,we use ERA5 meteor-ological products,including temperature,precipitation,and soil moisture,to explain the frequency of forest fires and the amount of radiant energy released per time unit by burning vegetation(fire radiative power,FRP).We explore the relation-ships between satellite-retrieved fire products and aerosol properties(aerosol optical depth,AOD),carbon monoxide(CO),formaldehyde(HCHO),and nitrogen dioxide(NO_(2))con-centrations over the PEEX domain,which covers different vegetation zones(***/grasslands,forest,arctic tun-dra)of Pan-Eurasia and *** analyse the concentrations of black carbon and absorbing organic carbon using groundbased AErosol RObotic *** analysis covers the months of may to August from 2002 to *** show posi-tive temperature trends in the Northern zone(>65°N)in June and August(1.56°C and 0.64°C,respectively);all statistically significant trends for precipitation and soil moisture are *** can explain increased fire activity in Siberia over the recent years(2019-2022).Over the whole PEEX domain,FC and FRP trends remain insignificant or negative;a decrease in AOD may address those negative *** show that intrasummer variations exist for cropland/grassland fires,which occur most often in may and August,while Siberian forest fires occur more often in July and *** show that CO concentration has been gradually decreasing in the last two decades in may and *** trends are negative in may,June,and over summer for all regions,in July in Europe,China,the Southern zone(may and

关键词： PEEX wild fires satellite trend enhancement ratios

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-merz Jorge Hernández-Campano Sergei A.Kirov Jesús m.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

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

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用于固态照明的mn^4+离子光谱学

发光学报 2020年第9期41卷 1011-1029页

作者： BRIK mikhail G 马崇庚 SRIVASTAVA Alok m PIASECKI michal 重庆邮电大学理学院&“重庆邮电大学-伦敦布鲁内尔大学”交叉创新研究院重庆400065 塔尔图大学物理所爱沙尼亚塔尔图50411 琴斯托霍瓦师范大学物理所波兰琴斯托霍瓦42200 戴恩特里公司通用电气顾问部美国克利夫兰44110 东欧国立大学固态物理系乌克兰卢茨克43025

mn^4+离子激活的荧光粉在固态照明领域作为红光发射的热点载体正日益受到关注。我们针对当前研究热度撰写了mn^4+离子光谱学的回顾,并在回顾中聚焦了许多对红色荧光粉商业研制有价值的重要基础研究点。这些研究点涵盖了如何理解自由和... 详细信息

mn^4+离子激活的荧光粉在固态照明领域作为红光发射的热点载体正日益受到关注。我们针对当前研究热度撰写了mn^4+离子光谱学的回顾,并在回顾中聚焦了许多对红色荧光粉商业研制有价值的重要基础研究点。这些研究点涵盖了如何理解自由和晶场状态下mn^4+离子的能级结构以及mn^4+发射波长对基质的依赖关系。此外,我们就如何实验调控mn^4+离子掺杂型荧光粉的发射波长和发光强度给出了许多实际可行的建议。更为重要的是,我们收集并讨论了100多种荧光粉基质中mn^4+离子光谱学参数,对它们的理解将会为未来mn^4+掺杂型红色荧光粉的实验开发奠定基础。

关键词： mn^4+离子红色荧光粉白光LED