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Superluminal Radio Source PKS 0420-014

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Chinese Physics Letters 1998年第7期15卷 545-546页

作者： HONG Xiao-yu JIANG Dong-rong SHEN zhi-qiang WAN tong-shan Shanghai Observatory Chinese Academy of SciencesShanghai 200030

The very long baseline interferometry result of a superluminal radio source PKS 0420-014 at 5 GHz with Shanghai(China),Urumqi(China),Noto(Italy),and HartRAO(South Africa)telescopes is *** motions of the relativistic jet components in the source are *** on the Self-Compton emission in a uniform spherical model,the beaming parameters of the source are *** results show that PKS 0420-014 has a high Doppler factor of 9.3,a Lorentz factor of 6.5,and a small angle of 5.5°to the line of sight.

关键词： interferometry relativistic Lorentz

Age-specific mortality and fecundity of a spider mite under diet restriction and delayed mating

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Insect Science 2022年第3期29卷 889-899页

作者： Guang-Yun Li zhi-qiang Zhang Centre for Biodiversity and Biosecurity School of Biological SciencesUniversity of AucklandAucklandNew Zealand Manaaki Whenua-Landcare Research AucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina

Numerous experimental life-history studies on aging are mainly baised on two classical models—fruit fly Drosophila melanogaster(Meigen)and nematode Caenorhab-ditis elegans(Maupas)—with relatively little attention given to other organisms with different life-history ***-spotted spider mite Tetranychus urticae Koch(Acari:Tetranychidae)differs from many other arthropods in that the females continue their growth in the early adult stage and can reproduce sexually and *** this study,the influences of dietary restriction and delayed mating on the aging patterns of the spider mite were examined with the prevailing survival and reproduction trade-off hypothesis of aging being *** sex-specific responses of the spider mites were *** females showed longevity extension on diet restriction(fasting for 2 days in every 4 days)compared with their counterparts being fed ad libitum,and after delayed mating for 9 days,while the males displayed a decrease in lifespan when experiencing diet restriction but were not significantly influenced by delayed *** analysis was used to investigate the relationship between mite survival and reproduction traits,including longevity,female lifetime reproduction,age at first reproduction,early reproductive efforts and late reproductive efforts,yielding no evidence for trade-offs between these life-history *** additive effects of dietary restriction and delayed mating in lifespan extension of female spider mites were confirmed,proving that diet restriction is a robust anti-aging intervention,and that later onset of reproduction can prolong adult lifespan in females.

关键词： age-specific mortality delayed mating diet restriction reproduction sex difference trade-off

On K_2-group of a Formal Matrix Ring

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1897-1906页

作者： Zi qiang FAN zhi Xiang YIN Department of Mathematics Anhui University of Science and Technology

Let S be a formal matrix ring, T the subring consisting of all diagonal elements, I the set consisting of all off-diagonal elements. Then I is a split radical ideal under certain conditions. In this paper, we show tha... 详细信息

关键词： K2 group relative K2 group extension of groups

Control of vortex-induced vibrations of the cylinder by using split-ter plates immersed in the cylinder wake at low Reynolds number

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Journal of Hydrodynamics 2020年第5期32卷 942-952页

作者： zhi-qiang Xin zhi-huang Wu Chui-jie Wu Dan Huang The College of Mechanics and Materials HoHai UniversityNanjing 211100China State Key Laboratory of Structural Analysis for Industrial Equipment and School of Aeronautics and Astronautics Dalian University of TechnologyDalianChina

The vortex-induced vibrations of a cylinder with two plates symmetrically distributed along the centerline of the wake are studied by using the fluid-structure interaction simulations on the Arbitrary Lagrangian-Eulerian *** this study,the different geo-metrical distribution parameters of the splitter plates and inflow velocities are taken into *** physical mechanisms of vortex-induced vibration of the cylinder with symmetrical plates are revealed from the cylinder amplitude,hydrodynamic force characteristics,vortex shedding frequency,and flow pattern *** results show that the dynamic interaction between the vortex shed from the oscillation cylinder and plates is responsible for the wake stabilization mechanism,and the stable wake and the dynamic response reduction of the main cylinder can be achieved at a wide range of reduced velocities by placing sym-metrical sheets at suitable locations.

关键词： Cylinder vortex-induced vibrations splitter plates vibration control flow pattern

Exact Convergence Rate of the Local Limit Theorem for a Branching Random Walk in Z^(d)with a Random Environment in Time

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 805-822页

作者： Jian-xin LIU zhi-qiang GAO School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China

Consider a branching random walk with a random environment in time in the d-dimensional integer *** branching mechanism is governed by a supercritical branching process,and the particles perform a lazy random walk with an independent,non-identical increment *** A■Z^(d),let Z_(n)(A)be the number of offsprings of generation n located in *** exact convergence rate of the local limit theorem for the counting measure Z_(n)(·)is *** partially extends the previous results for a simple branching random walk derived by Gao(2017,*** Appl.).

关键词： Branching random walk Random environment Local limit theorems Exact convergence rate

A curve-based material recognition method in MeV dual-energy X-ray imaging system

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Nuclear Science and Techniques 2016年第1期27卷 13-20页

作者： zhi-qiang Chen Tiao Zhao Liang Li Department of Engineering Physics Tsinghua University Key Laboratory of Particle and Radiation Imaging (TsinghuaUniversity) Ministry of Education

High-energy dual-energy X-ray digital radiography imaging is mainly used in the material recognition of cargo inspection. We introduce the development history and principle of the technology and describe the data process flow of our system. The system corrects original data to get a dual-energy transparence image. Material categories of all points in the image are identified by the classification curve,which is related to the X-ray energy spectrum. For the calibration of classification curve, our strategy involves a basic curve calibration and a real-time correction devoted to enhancing the classification accuracy. Image segmentation and denoising methods are applied to smooth the image. The image contains more information after colorization. Some results show that our methods achieve the desired effect.

关键词： X射线成像系统校准曲线材料识别识别方法数据处理流程透明图像分类精度实时校正

二维光晶格中旋转玻色-爱因斯坦凝聚基态中的涡旋分布

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原子与分子物理学报 2025年第1期42卷 118-126页

作者：张志强王平平吕亚南郑州商学院大学物理教研室郑州451200

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝... 详细信息

利用多重网格预条件共轭梯度法,研究了囚禁在二维光晶格与谐振势组成的复合势阱中的旋转玻色-爱因斯坦凝聚体中的涡旋分布,探讨了光晶格深度、晶格常数和凝聚体旋转频率对旋转凝聚体中涡旋分布的影响.结果表明,由于光晶格势阱的引入,凝聚体中产生涡旋,且涡旋位于外部势阱极小值处.随着光晶格势阱深度的增加,凝聚体集聚在光晶格势阱的底部,形成格点状分布,其中的涡旋形成涡旋对,并融合形成更大的涡旋.在晶格常数较小时,凝聚体中涡旋分布形成类似Abrikosov涡旋晶格,随着晶格常数的增加,凝聚体中涡旋的分布形式出现多样化,出现了内中外三层结构.随着旋转频率的增加,凝聚体中涡旋数目也随之增加,涡旋分布也更加复杂和富于变化,凝聚体密度分布范围也随着旋转频率的增加而扩展.当凝聚体旋转频率接近外部谐振势阱的谐振频率,即凝聚体处于最低朗道能级近似时,其中的涡旋数量大幅度增加,且出现涡旋成对组合与融合现象,并形成了涡旋斑图花纹.

关键词：波色-爱因斯坦凝聚涡旋二维光晶格复合势阱

Solving Generalized Non-degenerate Two-Mode Two-Photon Jaynes-Cummings Model by Supersymmetric Unitary Transformation

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Communications in Theoretical Physics 2002年第7期38卷 85-88页

作者： SONG tong-qiang ZHU Yue-Jin Department of Physics Ningbo University Ningbo 315211 China Department of Physics Ningbo University Ningbo 315211 China

Based on supersymmetric quantum mechanics theory, we introduced a supersymmetric unitary transfor mation to diagonalize the Hamiltonian of non-degenerate two-mode two-photon Jaynes-Cummings models which include any forms of intensity-dependent coupling, field-dependent detuning, and field nonlinearity. Its eigenvalue, eigenstates,and time evolution of state vector are obtained.

关键词： supersymmetric unitary transformation, Jaynes-Cumnings model

Rational Design of Biomolecules/Polymer Hybrids by Reversible Deactivation Radical Polymerization (RDRP) for Biomedical Applications

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Chinese Journal of Polymer Science 2021年第9期39卷 1093-1109页

作者： Jie Zhou Xiao-Yuan Zhang zhi-qiang Su State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Advanced Functional Polymer CompositesBeijing University of Chemical TechnologyBeijing 100029China

Hybrids,produced by hybridization of proteins,peptides,DNA,and other new biomolecules with polymers,often have unique functional *** properties,such as biocompatibility,stability and specificity,lead to various smart *** review mainly introduces biomolecule polymer hybrid materials by reversible deactivation radical polymerization(RDRP),emphasizing reverse addition-fragmentation chain transfer(RAFT)polymerization,and nitroxide mediated polymerization(NMP).It includes the methods of RDRP to improve the biocompatibility of biomedical materials and organisms by surface *** key to the current synthesis of biomolecule polymer hybrids is to control ***,this review describes several different kinds of biomolecule polymer hybrid materials and their applications in the biomedical *** progresses provide ideas for the investigation of biodegradable and highly bioactive biomedical soft tissue *** research hotspots of nanotechnology in biomedical fields are controlled drug release materials and gene therapy carrier *** showed that RDRP method could improve the therapeutic effect and reduce the dosage and side effects of the ***,by means of RDRP,the original materials can be modified to develop intelligent polymer materials as membrane materials with selective permeability and surface modification.

关键词： Biomolecule-polymer hybrids RDRP Biomedical applications Drug release Nanotechnology