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Simple Scheme for Directly Measuring Concurrence of Two-Qubit Pure States in One Step

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Communications in Theoretical Physics 2009年第2期51卷 252-254页

作者： YANG Rong-Can LIN Xiu HUANG zhi-ping LI Hong-cai School of Physics and Opto-Electronics Technology Fujian Normal University Fuzhou 350007 China

In the present work, a simple scheme for the direct measurement of the concurrence of two-qubit pure states is proposed. The scheme is based on trapped ions and only needs one step when the two identical pure states are given. The vibrational mode in our proposal is only virtually excited, which is important in view of ***, the scheme is feasible based on current technologies.

关键词： concurrence trapped ions measurement one step

Protective mechanism of testosterone on cognitive impairment in a rat model of Alzheimer's disease

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Neural Regeneration Research 2019年第4期14卷 649-657页

作者： Xu-Sheng Yan Zhan-Jun Yang Jian-Xin Jia Wei Song Xin Fang zhi-ping cai Dong-Sheng Huo He Wang Department of Human Anatomy Baotou Medical College School of Health Sciences University of NewcastleNewcastle Australia

Cognitive dysfunction in Alzheimer's disease is strongly associated with a reduction in synaptic plasticity, which may be induced by oxidative stress. Testosterone is beneficial in learning and memory, although the underlying protective mechanism of testosterone on cognitive performance remains unclear. This study explored the protective mechanism of a subcutaneous injection of 0.75 mg testosterone on cognitive dysfunction induced by bilateral injections of amyloid beta 1–42 oligomers into the lateral ventricles of male rats. Morris water maze test results demonstrated that testosterone treatment remarkably reduced escape latency and path length in Alzheimer's disease rat models. During probe trials, testosterone administration significantly elevated the percentage of time spent in the target quadrant and the number of platform crossings. However, flutamide, an androgen receptor antagonist, inhibited the protective effect of testosterone on cognitive performance in Alzheimer's disease rat models. Nissl staining, immunohistochemistry, western blot assay, and enzyme-linked immunosorbent assay results showed that the number of intact hippocampal pyramidal cells, the dendritic spine density in the hippocampal CA1 region, the immune response and expression level of postsynaptic density protein 95 in the hippocampus, and the activities of superoxide dismutase and glutathione peroxidase were increased with testosterone treatment. In contrast, testosterone treatment reduced malondialdehyde levels. Flutamide inhibited the effects of testosterone on all of these indicators. Our data showed that the protective effect of testosterone on cognitive dysfunction in Alzheimer's disease is mediated via androgen receptors to scavenge free radicals, thereby enhancing synaptic plasticity.

关键词： nerve regeneration Alzheimer’s disease testosterone cognitive dysfunction synaptic plasticity free radicals Morris water maze androgen receptor flutamide postsynaptic density protein 95 amyloid beta 1–42 neurodegenerative change neural regeneration

Sensitivity to Estimation Errors in Mean-variance Models

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Acta Mathematicae Applicatae Sinica 2003年第2期19卷 255-266页

作者： zhi-ping Chen, cai-e ZhaoDepartment of Scientific Computing and Applied Softwares, Faculty of Science, Xi’an Jiaotong University, Xi’an 710049, China Department of Scientific Computing and Applied Softwares Faculty of Science Xi'an Jiaotong University Xi'an China

Abstract In order to give a complex and accurate description about the sensitivity of efficient portfolios to changes in asset's expected returns, variances and covariances, the joint effect of estimation errors in means, variances and covariances on the efficient portfolio's weights is investigated in this paper. It is proved that the efficient portfolio's composition is a Lipschitz continuous, differentiable mapping of these parameters under suitable conditions. The change rate of the efficient portfolio's weights with respect to variations about risk-return estimations is derived by estimating the Lipschitz constant. Our general quantitative results show that the efficient portfolio's weights are normally not so sensitive to estimation errors about means and variances. Moreover, we point out those extreme cases which might cause stability problems and how to avoid them in practice. Preliminary numerical results are also provided as an illustration to our theoretical results.

关键词： Keywords The MV model estimation error sensitivity Lipschitz continuity

Ground State and Single Vortex for Bose-Einstein Condensates in Anisotropic Traps

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Communications in Theoretical Physics 2007年第6期47卷 1053-1057页

作者： XU zhi-Jun cai ping-Gen Department of Applied Physics Zhejiang University of Technology Hangzhou 310032 China The State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan 430071 China

For Bose-Einstein condensation of neutral atoms in anisotropic traps at zero temperature, we present simple analytical methods for computing the properties of ground state and single vortex of Bose-Einstein condensates, and compare those results to extensive numerical simulations. The critical angular velocity for production of vortices is calculated for both positive and negative scattering lengths a, and find an analytical expression for the large-N limit of the vortex critical angular velocity for a 〉0, and the critical number for condensate population approaches the point of collapse for a 〈 0, by using approximate variational method.

关键词： Bose-Einstein condensation G-P equation wave function vortex formation

A New Periodic Solution to Jacobi Elliptic Functions of MKdV Equation and BBM Equation

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 409-415页

作者： Hong-cai MA zhi-ping ZHANG Ai-ping DENG Department of Applied Mathematics College of Science Donghua University Shanghai 201620 China School of Mathematics and Information Sciences Henan University Kaifeng 475000 China

Based on the homogeneous balance method, the Jacobi elliptic expansion method and the auxiliary equation method, the first elliptic function equation is used to get a new kind of solutions of nonlinear evolution equations. New exact solutions to the Jacobi elliptic function of MKdV equations and Benjamin-Bona-Mahoney （BBM） equations are obtained with the aid of computer algebraic system Maple. The method is also valid for other （l＋l）-dimensional and higher dimensional systems.

关键词： (1+1)-dimensional MKdV equation BBM equation auxiliary equation method traveling wavesolution nonlinear

Hot deformation characterization and processing map of Cu-10 %Fe-1.5 %Ag in situ composite

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Rare Metals 2017年第11期36卷 912-918页

作者： Jun-Qing Guo He Yang ping Liu zhi-Wei cai State Key Laboratory of Solidification Processing Northwestern Polytechnical University School of Materials Science and Engineering University of Shanghai for Science and Technology School of Materials Science and Engineering University of Henan Science and Technology

The Cu-10 %Fe-1.5 %Ag in situ composite with high strength, high conductivity and low cost was prepared, and its hot deformation behavior was investi- gated by isothermal compression test with true strain of 0.69, temperature range of 750-950℃ and strain rate of 0.002-1.000 s-1. The flow stress-strain response shows the characterization of dynamic recrystallization （DRX）, and the peak stress increases gradually with deformation tem- perature decreasing and strain rate increasing. The defor- mation activation energy of the composite for DRX is calculated as 241.864 ***1-1. The constitutive relation of the composite was got by Arrhenius equation. Further- more, according to the dynamic material modeling and Kumar-Prasad＇s instability criteria, the processing map was constructed and the unsafe regions for hot deformation were analyzed. Based on the processing map and microstructural evolution, the optimal parameter range for hot deformation processing is 750-863℃ at the strain rate of 0.002-0.013 s-1.

关键词： Cu-10 %Fe-1.5 %Ag in situ composite Hotcompression test Deformation characterization Processingmap Dynamic recrystallization

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng cai Shengjun Miao Yuan Li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Characteristics Improvement of L-Band Superfluorescent Fiber Source Using Unpumped Erbium-Doped Fiber

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Chinese Physics Letters 2012年第8期29卷 131-134页

作者： WANG Xiu-Lin HUANG Wen-cai cai zhi-ping Department of Physics Jimei UniversityXiamen 361021 Department of Electronic Engineering Xiamen UniversityXiamen 361005

An effective method for the improvement of the characteristics of an erbium-doped L-band superfluorescent fiber source(SFS)is demonstrated using an unpumped erbium-doped fiber(EDF).With a suitable length of unpumped EDF section in the single-forward pumped configuration,broadening of the L-band spectral linewidth is achieved and the variation of mean wavelength versus pump power is eliminated.A mean wavelength stable L-band SFS with a spectral linewidth of 50.2 nm and an output power of 60.2 mW is obtained *** method of using unpumped EDF enables one to offer a stable and wideband L-band SFS with high flexibility and to overcome the shortcomings of the synchronous pumping technique.

关键词： pumped technique fiber

Influence of nitrogen implantation into HSS substrate on internal stress and adhesion strength of c-BN films

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中国有色金属学会会刊：英文版 2004年第z1期14卷 286-290页

作者： ZHANG ping cai zhi-hai TAN Jun XIONG Wan-quan National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

Cubic boron nitride(c-BN) films were deposited on HSS substrate implanted with nitrogen ion by RF-magnetron sputtering. The films were analyzed by bending beam method, scratch test, XRD and AFM. The results show that the implantation of N ion can reduce the internal stress and improve the adhesion strength of the *** critical load comes to 16.92N, compared to 1.75N of c-BN film on the unimplanted HSS. AFM shows that the surface of the c-BN film on the implanted HSS is low in roughness and small in grain size. The phase structure of the nitrogen implanted layer was analyzed by XRD. The influence of nitrogen implanted layer on the internal stress and adhesion strength of c-BN films were also investigated.

关键词： cubic boron nitride film HSS ion implantation internal stress adhesion