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Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power laser Science and Engineering 2024年第3期12卷 62-68页

作者： l.R.Yin X.f.li Y.J.Gu N.Cao Q.Kong M.Büscher S.M.Weng M.Chen Z.M.Sheng Key laboratory of Nuclear Physics and Ion-beam Application(MoE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key laboratory of High field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SANKEN(Institute of Scientific and Industrial Research) Osaka UniversityOsakaJapan Sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key laboratory for laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IfSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±Michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

Parameter-free Shifted laplacian Reconstruction for Multiple Kernel Clustering

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1072-1074页

作者： Xi Wu Zhenwen Ren f.Richard Yu the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010China the School of National Defence Science and Technology Southwest University of Science and TechnologyMianyang 621010 the Guangxi Key laboratory of Machine Vision and Intelligent Control Wuzhou UniversityWuzhou 543002 the Guangdong laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen 518060China

Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted laplacian *** MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within laplacian.

关键词： parameter letter Parameter

Quantum vortices get stretched

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frontiers of physics 2024年第3期19卷 225-227页

作者： Emanuel A.l.Henn São Carlos Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarkable phenomena in quantum physics. The onset of the quantum regime in liquid helium is visually striking, when the fluid flows without dissipation or detaches from a rotating bucket, remaining still upon soft rotations. The same phenomenon is present in the context of ultracold bosonic quantum gases where, most of the time, superfluidity walks hand-in-hand with the transition to Bose−Einstein condensation [3].

关键词： quantum rotating rotation

Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： Qi lü Bowen Ma School of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy

Some facets of the Mg/Na3VCr0.5fe0.5（PO4）3 battery

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Chinese Chemical letters 2024年第10期35卷 495-499页

作者： Gregorio f.Ortiz Xiamen Key laboratory of Optoelectronic Materials and Advanced Manufacturing Institute of Luminescent Materials and Information Displays College of Materials Science and Engineering Huaqiao University

Magnesium rechargeable batteries（MRBs） present opportunities for grid-scale energy storage applications as a complement to li-ion batteries（lIBS）. The major challenges are the low reversible capacity, inferior cycling stability and unsatisfactory energy densities. Na3VCr0.5fe0.5（PO4）3with a well-defined NASIONtype structure is used as cathode in Mg cell. Two-electrons reaction（～116 m Ah/g）, 1.5 V average voltage and 65% of capacity retention over 100 cycles are accomplished. Mg is inserted by a biphasic reaction with the participation of V3+/V4+/V5+redox couples in the electrochemical reaction while the non-active redox couples such as Cr3+/Cr4+and fe2+/fe3+served as stabilizer to buffer the volume variation. A thermal stability up to ～412 °C is also exhibited. Therefore, incorporating a mixture of three transition metal（V/Cr/fe） in this type of structures will broaden new perspectives for realizing high performance cathodes for MRBs.

关键词： Iron and chromium doping Mg batteries Multi-electron reaction Na3VCr0.5fe0.5(PO4)3 NASICON

Heat and mass transfer of a circular porous moist object located in a triangular shaped vented cavity

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Journal of Central South University 2024年第6期31卷 1956-1972页

作者： SElIMEfENDIGIl fatih OZCAN COBAN Seda OZTOP Hakan f Department of Mechanical Engineering College of EngineeringKing Faisal UniversityAl Ahsa 31982Saudi Arabia Department of Mechanical Engineering Manisa Celal Bayar UniversityManisa 45140Turkey Department of Mechanical Engineering Technology FacultyFırat UniversityElazığTurkey

Heat and mass transfer of a circular-shaped porous moist object inside a two-dimensional triangle cavity is investigated by using finite element *** porous object is considered to be a moist food sample,located in the middle of the cavity with inlet and outlet ports with different configurations of inlet/outlet *** drying performance is numerically assessed for different values of Reynolds numbers(between 50 and 250),dry air inlet temperature(between 40 and 80℃)and different locations of the *** is observed that changing the port locations has significant impacts on the flow recirculaitons inside the triangular chamber while convective drying performance is highly *** moisture content reduces with longer time and for higher Reynolds number(Re)*** P4 where inlet and outlet ports are in the middle of the walls provides the most effective configuration in terms of convective drying performance while the worst case is seen for P1 case where inlet and outlet are closer to the corners of the *** is a 192% difference between the moisture reduction of these two cases at Re=250,T=80℃ and t=120 min.

关键词： convective drying porous domain cavity flow inlet/exit port finite element method

Inflow and outflow permeability tests in a very soft clay under low stresses

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： J.W.S.Vargas f.A.B.Danziger f.R.lopes T.lunne federal University of Rio de Janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the BAT probe at SarapuíII soft clay test site are presented.A description of the BAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for SarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test Soft clay BAT probe Inflow and outflow tests

Rogue wave solutions and rogue-breather solutions to the focusing nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 33-41页

作者： Si-Jia Chen Xing lü College of Science Tianjin University of TechnologyTianjin 300384People's Republic of China Department of Mathematics Beijing Jiaotong UniversityBeijing 100044People's Republic of China Beijing laboratory of National Economic Security Early-warning Engineering Beijing Jiaotong UniversityBeijing 100044People's Republic of China

Based on the long wave limit method,the general form of the second-order and third-order rogue wave solutions to the focusing nonlinear Schr?dinger equation are given by introducing some arbitrary *** interaction solutions between the first-order rogue wave and one-breather wave are constructed by taking a long wave limit on the two-breather *** applying the same method to the three-breather solutions,two types of interaction solutions are obtained,namely the first-order rogue wave and two breather waves,the second-order rogue wave and one-breather wave,*** influence of the parameters related to the phase on the interaction phenomena is graphically *** occur among the rogue waves and breather *** the collisions,the shape of them remains *** abundant interaction phenomena in this paper will contribute to a better understanding of the propagation and control of nonlinear waves.

关键词： nonlinear Schrodinger equation rogue wave solutions interaction solutions

基于深度神经网络模拟复杂多孔介质中两相驱替过程

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石油勘探与开发 2024年第5期51卷 1126-1140页

作者： ASADOlAHPOUR Seyed Reza JIANG Zeyun lewis Helen 闵超赫瑞瓦特大学能源、地球科学、基础设施与社会学院地球能源工程研究所爱丁堡EH144AS英国西南石油大学理学院成都610500 油气藏地质及开发工程全国重点实验室西南石油大学成都610500

为了预测复杂孔隙结构中毛管压力主导下两相流排驱过程中的流体分布,从仿真多孔介质和岩石CT图像中抽取子样本,并采用孔隙形态模拟器(PMS)生成流体分布,以创建多样化的数据集,将距离图及像素大小、界面张力、接触角、压力作为输入参数,... 详细信息

为了预测复杂孔隙结构中毛管压力主导下两相流排驱过程中的流体分布,从仿真多孔介质和岩石CT图像中抽取子样本,并采用孔隙形态模拟器(PMS)生成流体分布,以创建多样化的数据集,将距离图及像素大小、界面张力、接触角、压力作为输入参数,通过改造、训练、评估卷积神经网络(CNN)、递归神经网络(RNN)和视觉转换器(ViT),优选用于预测流体分布的模型。模拟分析表明,常用的卷积和递归神经网络在捕捉流体连通性方面存在不足。基于ViT构建了一个高维视觉转换器(HD-ViT),该转换器先忽略孔隙的空间位置仅根据其大小进行排驱,再在后处理步骤中追加流体连通要求,这种方法允许在任何坐标方向预设出入口,并使用不同尺寸和不同分辨率的图像进行渗流状态推断。通过在砂岩和碳酸盐岩大图像上验证,并与微流控驱替测试的实验结果比较,证实了HD-ViT模型的有效性、精确性和速度优势,且在捕捉孔隙尺度三维流动方面存在较大的潜力。

关键词：两相驱替流体分布深度神经网络视觉转换器孔隙形态模拟器大数据集

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