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Structural and Spacial Characters of Neutron Star in Relativistic σ-ω Model

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Communications in Theoretical Physics 2006年第5期45卷 853-857页

作者： WEN De-hua hu jian-xun LIU Liang-Gang Department of Mathematics Zhongshan University Guangzhou 510275 China Department of Physics South China University of Technology Guangzhou 510641 China Department of Physics Zhongshan University Guangzhou 510275 China

The analytical and numerical solutions of structure and curvature of two kinds of static spherically symmetric neutron stars are calculated. The results show that Ricci tensor and curvature scalar cannot denote the curly character of the space directly, however, to static spherically symmetric stars, these two quantities can present the relative curly degree of the space and the matter distribution to a certain extent.

关键词： static spherically symmetric star neutron star structure curvature scalar

Frame Dragging Effect on Properties of Rotating Neutron Stars with Strong Magnetic Field

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Communications in Theoretical Physics 2008年第12期50卷 1469-1472页

作者： GUO Yu-Wu WEN De-hua hu jian-xun Department of Mathematics Zhongshan University Guangzhou 510275 China Department of Physics South China University of Technology Guangzhou 510641 China

The general relativistic frame dragging effect on the properties,such as the moments of inertia and the radiiof gyration of fast rotating neutron stars with a uniform strong magnetic field,is calculated accurate to the first orderin the uniform angular *** results show that compared with the corresponding non-rotating static sphericalsymmetric neutron star with a weaker magnetic field,a fast rotating neutron star(millisecond pulsar)with a strongermagnetic field has a relative smaller moment of inertia and radius of gyration.

关键词： rotating neutron star frame dragging effect moment of inertia magnetic field

On the Quantum Cohomology of Blow-ups of Four-dimensional Quadrics

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Acta Mathematica Sinica,English Series 2024年第1期40卷 313-328页

作者： jian xun hu hua Zhong KE Chang Zheng LI Lei SONG School of Mathematics Sun Yat-sen UniversityGuangzhou 510275P.R.China

We propose a conjecture relevant to Galkin’s lower bound conjecture,and verify it for the blow-ups of a four-dimensional quadric at a point or along a projective *** also show that Conjecture O holds in these two cases.

关键词： Quantum cohomology blow-up quadric hypersurface

Study of the vibrational photochemical reation of UF_6+HCl and its isotopic selectivity

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Chinese Journal of Chemistry 1993年第2期11卷 97-104页

作者： XU,Bao-Yu LIU,Yong DONG,Wen-Bo ZHAO,Wei hu,jian-xun ZHENG,Cheng-Fa Nuclear Science Department,Fudan University,Shanghai 200433 Nuclear Science Department Fudan University Shanghai 200433

The photochemical vibrational reaction of UF_6+HCl was investigated by exciting the ternary overtone of 3ν_3 of UF_6 in an intracavity CO laser *** was found that the rate of the laser-driven reaction was much greater than that of the thermal reaction and this photochemical process had an isotopic *** uranium isotope enrichment factors measured in experiments wore around 1,007 in a single step.

关键词： Study of the vibrational photochemical reation of UF6+HCl and its isotopic selectivity UF HCl

Active Fault Tolerant Nonsingular Terminal Sliding Mode Control for Electromechanical System Based on Support Vector Machine

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Chinese Journal of Mechanical Engineering 2024年第3期37卷 189-203页

作者： jian hu Zhengyin Yang jianyong Yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

Effective fault diagnosis and fault-tolerant control method for aeronautics electromechanical actuator is concerned in this *** borrowing the advantages of model-driven and data-driven methods,a fault tolerant nonsingular terminal sliding mode control method based on support vector machine(SVM)is proposed.A SVM is designed to estimate the fault by off-line learning from small sample data with solving convex quadratic programming method and is introduced into a high-gain observer,so as to improve the state estimation and fault detection accuracy when the fault *** state estimation value of the observer is used for state reconfiguration.A novel nonsingular terminal sliding mode surface is designed,and Lyapunov theorem is used to derive a parameter adaptation law and a control *** is guaranteed that the proposed controller can achieve asymptotical stability which is superior to many advanced fault-tolerant *** addition,the parameter estimation also can help to diagnose the system faults because the faults can be reflected by the parameters *** comparative simulation and experimental results illustrate the effectiveness and advancement of the proposed controller compared with several other main-stream controllers.

关键词： Aeronautics electromechanical actuator Fault tolerant control Support vector machine State observer Parametric uncertainty

Reaction mechanism between Al_(2)O_(3)–MgO refractory materials and rare earth high-carbon heavy rail steel

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Journal of Iron and Steel Research International 2024年第5期31卷 1153-1163页

作者： Yi Wang Guang-jie Song Ping Shen jian-zhong He Da-xian Zhang jian-xun Fu Center for Advanced Solidification Technology(CAST) School of Materials Science and EngineeringState Key Laboratory of Advanced Special SteelShanghai UniversityShanghai200444China State Key Laboratory of Baiyunebo Rare Earth Resources Research and Comprehensive Utilization Baotou014030Inner MongoliaChina Inner Mongolia Baotou Steel Union Co. Ltd.Baotou014030Inner MongoliaChina

Submerged entry nozzle(SEN)clogging is a major problem affecting the production quality of rare earth steel,and finding a suitable refractory outlet can significantly reduce production *** explore the relationship between refractory composition and interface interaction,unprotected coated Al_(2)O_(3)–MgO refractories and SiO2-coated Al_(2)O_(3)–MgO refractories were added to rare earth high-carbon heavy rail steel under laboratory conditions,and the Al_(2)O_(3)–MgO refractory was found to be more *** results show that,from the epoxy resin side to the refractory side,the contour of the refractory interface reaction layer can be divided into two main layers:an iron-rich reaction layer and an iron-poor reaction *** based on the spherical model suggest that the adhesion force is proportional to the size of the refractory particles and inclusions,and the same result applies to the surface *** the inclusions at a smaller size has a specific effect on alleviating the erosion of *** with the erosion mechanism of Al_(2)O_(3)–MgO refractories,the interface reaction mechanism between Al_(2)O_(3)–MgO refractories and molten steel was proposed,which provides ideas for solving SEN clogging.

关键词： Rare earth high-carbon heavy rail steel Al_(2)O_(3)-MgO refractory Adhesion Surface tension Interface interaction

基于GIS技术的石羊河流域地下水资源时空格局分析

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中国沙漠 2008年第4期28卷 781-786页

作者：胡建勋甘肃省水文水资源勘测局甘肃兰州730000

以地下水取水许可数据为主,结合社会经济等相关要素,在石羊河流域建立地下水取水许可GIS空间数据库,并对其进行分析、统计、查询和图表输出,辅助流域的取水许可管理程序,服务于流域的水资源综合管理。通过这一过程,对石羊河流域在水资... 详细信息

以地下水取水许可数据为主,结合社会经济等相关要素,在石羊河流域建立地下水取水许可GIS空间数据库,并对其进行分析、统计、查询和图表输出,辅助流域的取水许可管理程序,服务于流域的水资源综合管理。通过这一过程,对石羊河流域在水资源管理中存在的问题进行分析、研究,并提出了相应的管理对策,目的在于使水资源管理政策更为科学合理,具有一定的现实意义。

关键词：石羊河流域地下水资源 GIS技术

Corrosion behavior of pure metals(Ni and Ti)and alloys(316H SS and GH3535)in liquid GaInSn

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Nuclear Science and Techniques 2024年第3期35卷 70-83页

作者： jian-hui Yu Hong-Xia Xu Xiang-Xi Ye Bin Leng Han-xun Qiu Xing-Tai Zhou School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

In this study,the interactions between a Ga-based liquid metal,GaInSn,and several metal materials,including pure metals(Ni and Ti)and alloys(316H stainless steel(SS)and GH3535),at 650℃were *** aim was to evaluate the corrosion performance and select a suitable candidate material for use as a molten salt manometer diaphragm in thermal energy storage *** results indicated that the alloys(316H SS and GH3535)exhibited less corrosion than pure metals(Ni and Ti)in liquid ***-rich binary intermetallic compounds were found to form on the surfaces of all the tested metal materials exposed to liquid GaInSn,as a result of the decomposition of liquid GaInSn and its reaction with the constituent elements of the metal *** corrosion mechanism for all the tested materials exposed to liquid GaInSn was also investigated and proposed,which may aid in selecting the optimal candidate material when liquid GaInSn is used as the pressure-sensing medium.

关键词： Metal materials Liquid GaInSn Corrosion Intermetallic compounds Thermal energy storage systems

±800kV特高压直流线路带电作业安全防护用具的分析

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高电压技术 2010年第10期36卷 2357-2361页

作者：胡毅刘凯胡建勋刘庭肖宾国网电力科学研究院武汉430074

为保证±800kV特高压直流线路带电作业人员的安全,首先通过分析、比较以及试验研究,得出安全防护用具应满足:屏蔽服内场强≤15kV/m,人体裸露部位局部最大场强≤240kV/m;屏蔽服内流经人体电流≤50μA;屏蔽服载流容量满足电位转移的要求... 详细信息

为保证±800kV特高压直流线路带电作业人员的安全,首先通过分析、比较以及试验研究,得出安全防护用具应满足:屏蔽服内场强≤15kV/m,人体裸露部位局部最大场强≤240kV/m;屏蔽服内流经人体电流≤50μA;屏蔽服载流容量满足电位转移的要求。然后据此研制了专用屏蔽服,并依据标准对屏蔽服进行了测试。结果表明:交流屏蔽效率为69.44dB,直流屏蔽效率≥57dB,满足电场防护要求;可阻挡>99.8%的离子电流,满足电流防护要求;脉冲电流作用下无可察觉温升,满足电位转移要求。结合在实际线路中的应用表明,该屏蔽服可满足±800kV特高压直流线路带电作业安全防护要求。

关键词：特高压直流带电作业安全防护离子电流合成场屏蔽服