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International Journal of Sediment Research 2013年第1期28卷 34-45页

作者： C.HEIlIGER n.B.KAyE f.y.TESTIK Civil Engineering Clemson UniversityClemsonSC29634USA

The results of a simple computational model for differential settling are presented illustrating the significant role that particle size distribution plays in collision frequency and sedimentation rate of particles in a quiescent environment. The model tracks a large number of particles（order 10;） with log-normally distributed diameters,as they settle at their Stokes settling *** collisions are detected and result in larger particles that fall more rapidly.A number of simplifying assumptions are made in the model in order to avoid empirical correlations for phenomena such as collision efficiency and particle *** simplifying assumptions were needed to isolate and quantify the role of the particle size *** concentration profiles indicate that,even in the absence of collisions, the standard deviation（σ;） of the particle size strongly influences the bulk mass settling rate as,for largerσ;, more mass is concentrated in larger,faster falling *** collision frequency is also a strong function ofσ;. for a given mass concentration the collision frequency first increases linearly with increasingσ;as greater variation in particle size leads to greater variation in particle velocity,and shorter times for particles to catch each *** largerσ;more mass is concentrated in larger particles,so,for a given mass concentration,there are fewer particles per unit volume,increasing the mean distance between the particles and reducing the collision *** implications of these results for sedimentation measurement using optical attenuation techniques are discussed.

关键词： Settling Sediment size distribution Sediment collision frequency Coefficient of variation

Effect of perforation on flow past a conic cylinder at Re =100: wavy vortex and sign laws

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Acta Mechanica Sinica 2018年第5期34卷 812-829页

作者： l.M.lin X.f.Zhong y.X.Wu Key laboratory for Mechanics in fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

In order to find the intrinsic physical mechanism of the original Kármán vortex wavily distorted across the span due to the introduction of three-dimensional (3-D) geometric disturbances,a flow past a peak-perforated conic shroud is numerically simulated at a Reynolds number of *** on previous work by Meiburg and lasheras (1988),the streamwise and vertical interactions with spanwise vortices are introduced and *** vortex-shedding patterns in the near wake for different flow regimes are reinspected and illustrated from the view of these two ***,in regime Ⅰ,spanwise vortices are a little distorted due to the weak *** in regime Ⅱ,spanwise vortices,even though curved obviously,are still shed synchronously with moderate streamwise and vertical *** in regime Ⅲ,violently wavy spanwise vortices in some vortex-shedding patterns,typically an Ω-type vortex,are mainly attributed to the strong vertical interactions,while other cases,such as multiple vortex-shedding patterns in sub-regime Ⅲ-D,are resulted from complex streamwise and vertical interactions.A special phenomenon,spacial distribution of streamwise and vertical components of vorticity with specific signs in the near wake,is analyzed based on two models of streamwise and vertical vortices in explaining physical reasons of top and bottom shear layers wavily varied across the *** these two models and above two interactions are *** two sign laws are summarized:the first sign law for streamwise and vertical components of vorticity is positive in the upper shear layer,but negative in the lower shear layer,while the second sign law for three vorticity components is always negative in the wake.

关键词： Vortex-shedding pattern flow control Vortex dynamics Conic disturbance Perforation Sign law

Effect of perforation on flow past a conic cylinder at Re=100:vortex-shedding pattern and force history

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Acta Mechanica Sinica 2018年第2期34卷 238-256页

作者： l.M.lin X.f.Zhong y.X.Wu Key laboratory for Mechanics in fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The flow past a circular-section cylinder with a conic shroud perforated with four holes at the peak was simulated numerically at Re = 100, considering two factors, *** angle of attack and the diameter of the holes. The effects of the perforated conic shroud on the vortex shedding pattern in the near wake was mainly investigated, as well as the time history of the drag and lift forces. In the investigated parameter space, three flow regimes were generally identified, corresponding to weak, moderate, and strong disturbance *** regime I, the wake can mainly be described by alternately shedding Kármán or Kármán-like vortices. In regime II, the spanwise vortices are obviously disturbed along the span due to the appearance of additional vorticity components and their interactions with the spanwise vortices, but still shed in synchronization along the spanwise direction. In regime III,the typical Kármán vortices partially or totally disappear,and some new vortex shedding patterns appear, such as-type, obliquely shedding, and crossed spanwise vortices with opposite sign. Corresponding to these complex vortex shedding patterns in the near wake, the fluid forces no longer oscillate regularly at a single vortex shedding frequency, but rather with a lower modulation frequency and multiple amplitudes. An overview of these flow regimes is presented.

关键词： Vortex shedding pattern fluid forces flow control Conical shroud Perforation

Ground-based and additional science support for SMIlE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter M.Dunlop C.forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.fear D.G.Sibeck M.Connors T.yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.freeman D.-S.Han M.D.Hartinger S.-y.W.Hsieh Z.-J.Hu M.K.James l.Juusola K.Kauristie E.A.Kronberg M.lester J.Manuel J.Matzka I.McCrea y.Miyoshi J.Rae l.Ren f.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.yan J.Zhang Q.-H.Zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada ESTEC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China finnish Meteorological Institute(fMI) Finland Department of Earth and Environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GfZ German Research Centre for Geosciences PotsdamGermany nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 northumbria University Newcastle upon TyneTyne and WearUK NE18ST national Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere link Explorer(SMIlE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMIlE ***,we describe current community efforts to prepare for SMIlE,and the benefits and context various experiments that have explicitly expressed support for SMIlE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SMIlE Data fusion facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMIlE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMIlE conjunctions missions

Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

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Chinese Physics C 2024年第2期48卷 91-103页

作者： f.A.Rasulova n.V.Aksenov S.I.Alekseev R.A.Aliev S.S.Belyshev I.Chuprakov n.yu.fursova A.S.Madumarov J.H.Khushvaktov A.A.Kuznetsov B.S.yuldashev Joint Institute for nuclear Research DubnaRussia Institute of nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan TashkentUzbekistan faculty of Chemistry of lomonosov Moscow State University MoscowRussia national Research Center"Kurchatov Institute" MoscowRussia Skobeltsyn Institute of nuclear Physics of lomonosov Moscow State University MoscowRussia faculty of Physics of lomonosov Moscow State University MoscowRussia Institute of nuclear Physics AlmatyRepublic of Kazakhstan

In this study,experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TAlyS with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

Eco-Epidemiological Characteristics of Human Rabies in Côte d’Ivoire, 2012-2017

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Advances in Infectious Diseases 2024年第1期14卷 13-23页

作者： Zamina Bi yourou Guillaume Tiembré Issiaka Konan loukou leandre Bama Martial yapi Ellélé Aimé Gouzilé Assikohon Pulchérie Dagnan n’Cho Simplice national Institute of Public Hygiene Abidjan C&#244te d’Ivoire Département de Santé Publique et Spécialités UFR des Sciences Médicales d’Abidjan Université Félix HOUPHOU&#203T-BOIGNY de Cocody Abidjan C&#244te d’Ivoire Institut national de Santé Publique Abidjan C&#244te d’Ivoire

Introduction: Human rabies is a major public health problem in many African countries, including Côte d’Ivoire. The present work aims at describing the eco-epidemiological characteristics of human rabies cases recorded in Côte d’Ivoire. Methods: This was a retrospective and prospective cross-sectional descriptive study based on epidemiological surveillance data that ran from september 2014 to december 2017. The clinical data were extracted from the database of the human rabies epidemiological surveillance management service of the national Institute of Public Hygiene’s rabies centre. These data cover the period from 1 January 2012 to 31 December 2017. Results: Human rabies is endemic in Côte d’Ivoire, with most people exposed in the south and especially in the west of the country. There was no association between any of the climatological parameters (temperature, humidity, rainfall) and the occurrence of human rabies during the months of exposure to rabies infection. Conclusion: Ultimately, effective prevention and control of human rabies requires a thorough understanding of the links between climatological parameters and rabies. Health authorities must take ownership of these results if we are to achieve our goal of eliminating rabies by 2030.

关键词： Human Rabies Season Climate Abidjan Ivory Coast

Shock compression and spallation damage of high-entropy alloy Al_(0.1)CoCrfeni

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Journal of Materials Science & Technology 2022年第33期128卷 1-9页

作者： n.B.Zhang J.Xu Z.D.feng y.f.Sun J.y.Huang X.J.Zhao X.H.yao S.Chen l.lu S.n.luo Key laboratory of Advanced Technologies of Materials Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China The Peac Institute of Multiscale Sciences Chengdu 610031China Department of Engineering Mechanics South China University of TechnologyGuangzhou 510641China

Shock compression and spallation damage of a face-center cubic phase high-entropy alloy(HEA)Al_(0.1)CoCrfeni were investigated via plate impact experiments along with free surface velocity *** samples were characterized with transmission electron microscopy and electron backscatter *** Hugoniot equation of state and spall strength at different impact strengths were *** exists a power-law relation between spall strength and strain *** spall strength of Al_(0.1)CoCrfeni HEA is about 50%higher than those of previously studied HEAs and comparable to those widely applied structural stainless steels at the same shock *** glide and stacking faults are the important deformation mechanisms in the Al_(0.1)CoCrfeni *** are only observed at high shock *** in the Al_(0.1)CoCrfeni HEA is ductile in *** are nucleated preferentially in grain interiors,and the intragranular voids show a strong dependence on grain boundary misorientation and peak stress.

关键词： Al_(0.1)CoCrfeni High-entropy alloy Hugoniot Spall damage Microstructure

Response of ants to grazing disturbance at the central Monte Desert of Argentina: community descriptors and functional group scheme

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Journal of Arid land 2014年第1期6卷 117-127页

作者： Silvia ClAVER Susana l SIlnIK florencia f CAMPón Entomology lab IADIZA-CONICET

livestock ranching is one of the main productive activities in arid regions of the *** produces changes in animal as well as plant communities(***,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community *** described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group *** used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent *** of the 27 recorded species showed significant differences in their abundance and two species were absent at the *** richness and diversity did not reflect these differences,functional groups *** Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the *** study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.

关键词： ants cattle grazing functional groups richness diversity arid zones Monte Desert

Superior antibody and membrane protein‑specific T‑cell responses to CoronaVac by intradermal versus intramuscular routes in adolescents

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World Journal of Pediatrics 2024年第4期20卷 353-370页

作者： Jaime S.Rosa Duque Samuel M.S.Cheng Carolyn A.Cohen Daniel leung Xiwei Wang Xiaofeng Mu yuet Chung Tsun Ming lau Manni Wang Wenyue Zhang yanmei Zhang Howard H.W.Wong leo C.H.Tsang Sara Chaothai Tsz Chun Kwan John K.C.li Karl C.K.Chan leo l.H.luk Jenson C.H.Ho Wing yan li Amos M.T.lee Jennifer H.y.lam Sau Man Chan Wilfred H.S.Wong Issan y.S.Tam Masashi Mori Sophie A.Valkenburg Malik Peiris Wenwei Tu yu lung lau Department of Paediatrics and Adolescent Medicine The University of Hong KongHong KongChina School of Public Health The University of Hong KongHong KongChina HKU‑Pasteur Research Pole School of Public HealthThe University of Hong KongHong KongChina Research Institute for Bioresources and Biotechnology Ishikawa Prefectural UniversityNonoichiJapan Department of Microbiology and Immunology Peter Doherty Institute for Infectionand ImmunityUniversity of MelbourneMelbourneVICAustralia Center for Immunology and Infection C2i Hong KongChina

Background Optimising the immunogenicity of COVID-19 vaccines to improve their protection against disease is *** dosing by intradermal(ID)administration has been shown to be equally immunogenic as intramuscular(IM)administration for several vaccines,but the immunogenicity of ID inactivated whole severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)at the full dose is *** study(nCT04800133)investigated the superiority of antibody and T-cell responses of full-dose CoronaVac by ID over IM administration in *** Participants aged 11–17 years received two doses of IM or ID vaccine,followed by the 3rd dose 13–42 days *** and cellular immunogenicity outcomes were measured post-dose 2(IM-CC versus ID-CC)and post-dose 3(IMCCC versus ID-CCC).Doses 2 and 3 were administered to 173 and 104 adolescents,*** Spike protein(S)immunoglobulin G(IgG),S-receptor-binding domain(RBD)IgG,S IgG fcγreceptor IIIa(fcγRIIIa)-binding,SnM[sum of individual(S),nucleocapsid protein(n),and membrane protein(M)peptide pool]-specific interleukin-2(Il-2)+CD4^(+),SnM-specific Il-2^(+)CD8^(+),S-specific Il-2^(+)CD8^(+),n-specific Il-2^(+)CD4^(+),n-specific Il-2^(+)CD8^(+)and M-specific Il-2^(+)CD4^(+)responses fulfilled the superior and non-inferior criteria for ID-CC compared to IM-CC,whereas IgG avidity was *** ID-CCC,S-RBD IgG,surrogate virus neutralisation test,90%plaque reduction neutralisation titre(PRnT90),PRnT50,S IgG avidity,S IgG fcγRIIIa-binding,M-specific Il-2^(+)CD4^(+),interferon-γ+CD8^(+)and Il-2^(+)CD8^(+)responses were superior and non-inferior to *** estimated vaccine efficacies were 49%,52%,66%and 79%for IM-CC,ID-CC,IM-CCC and ID-CCC,*** ID groups reported more local,mild adverse *** This is the first study to demonstrate superior antibody and M-specific T-cell responses by ID inactivated SARSCoV-2 vaccination and serves as the basis for future research to improve the

关键词： CoronaVac Coronavirus disease 2019 Immunity Intradermal Vaccine

Effect of electric boundary conditions on crack propagation in ferroelectric ceramics

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Acta Mechanica Sinica 2014年第2期30卷 153-160页

作者： f.-X. li y.Sun R.K.n.D.Rajapakse State Key laboratory for Turbulence and Complex Systems College of EngineeringPeking University faculty of Applied Sciences Simon Fraser University

In this paper, the effect of electric boundary conditions on Mode I crack propagation in ferroelectric ceramics is studied by using both linear and nonlinear piezoelectric fracture mechanics. In linear analysis, impermeable cracks under open circuit and short circuit are analyzed using the Stroh formalism and a rescaling method. It is shown that the energy release rate in short circuit is larger than that in open circuit. In nonlinear analysis, permeable crack conditions are used and the nonlinear effect of domain switching near a crack tip is considered using an energy-based switching criterion proposed by Hwang et al.（Acta Metal. Mater.,1995）. In open circuit, a large depolarization field induced by domain switching makes switching much more diffcult than that in short circuit. Analysis shows that the energy release rate in short circuit is still larger than that in open circuit, and is also larger than the linear result. Consequently,whether using linear or nonlinear fracture analysis, a crack is found easier to propagate in short circuit than in open circuit, which is consistent with the experimental observations of Kounga njiwa et al.（Eng. fract. Mech., 2006）.

关键词： ferroelectric ceramics Crack propagation En-ergy release rate Electric boundary conditions Domain switching