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Effects of Density-Dependent Quark Mass on Phase Diagram of Color-Flavor-Locked Quark Matter

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Communications in Theoretical Physics 2006年第4期45卷 691-696页

作者： ZHANG xiao-bing li Xue-Qian Department of Physics Nankai University Tianjin 300071 China

Considering the density dependence of quark mass, we investigate the phase transition between the （unpaired） strange quark matter and the color-flavor-locked matter, which are supposed to be two candidates for the ground state of strongly interacting matter. We lind that if the current mass of strange quark m, is smmall, the strange quark matter remains stable unless the baryon density is very high. If m, is large, the phase transition from the strange quark matter to the color-flavor-locked matter in particular to its gapless phase is found to be different from the results predicted by previous works. A complicated phase diagram of three-flavor quark matter is presented, in which the color-flavor-locked phase region is suppressed for moderate densities.

关键词： strange quark matter color-flavor locked quark matter pairing

Asymmetry in interface and bending property of Al/Cu/Al bimetallic laminates

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Rare Metals 2014年第5期33卷 556-562页

作者： xiao-bing li Guo-Yin Zu Ping Wang School of Materials and Metallurgy Northeastern University

This work was aimed to study the interfacial microstructures and three-point bending properties of Al/Cu/Al bimetallic laminates produced by the asymmetrical roll bonding and annealing. It is found that the microstructure and bonding strength of the Al/Cu interface are different with those of the Cu/Al interface. The interfacial microstructure of Cu/Al interface is improved due to the large interfacial plastic deformation caused by the different rotation speeds of roll in the asymmetrical roll bonding process. The bonding strength between Al and Cu layer can be enhanced by the moderate atomic diffusion, but is dramatically depressed by the formation of intermetallic compounds in the *** bending strength of bimetallic laminates is enhanced when the Cu/Al interface is loaded in tension because of the improvement of stress transition and damping by the Cu/Al interface during the three-point bending deformation. The bending fracture reveals that the interfacial cracks can be inhibited from the restricted stress concentration in the improved Cu/Al interface.

关键词： Layered structures Bending test Interface Shear deformation

Microstructure and properties of a wear resistant Al-25Si-4Cu-1Mg coating prepared by supersonic plasma spraying

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1287-1294页

作者： Tian-shun Dong Ming liu Yang Feng Guo-lu li xiao-bing li School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China Key Laboratory for New Type of Function Material in Hebei Province Hebei University of TechnologyTianjin 300130China National Key Laboratory for Remanufacturing Academy of Armored Forces EngineeringBeijing 100072China

A high content silicon aluminum alloy(Al-25Si-4Cu-1Mg)coating was prepared on a 2A12 aluminum alloy by supersonic plasma *** morphology and microstructure of the coating were observed and *** hardness,elastic modulus,and bonding strength of the coating were *** wear resistance of the coating and 2A12 aluminum alloy was studied by friction and wear *** results indicated that the coating was compact and the porosity was only 1.5%.The phase of the coating was mainly composed ofα-Al andβ-Si as well as some hard particles(Al9Si,Al3.21Si0.47,and CuAl2).The average microhardness of the coating was HV 242,which was greater than that of 2A12 aluminum alloy(HV 110).The wear resistance of the coating was superior to 2A12 aluminum *** wear mechanism of the 2A12 aluminum alloy was primarily adhesive wear,while that of the coating was primarily abrasive ***,it is possible to prepare a high content silicon aluminum alloy coating with good wear resistance on an aluminum alloy by supersonic plasma spraying.

关键词： coating high silicon aluminum alloy microstructure mechanical properties wear resistance

Deformation behavior and crack propagation on interface of Al/Cu laminated composites in uniaxial tensile test

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Rare Metals 2020年第3期39卷 296-303页

作者： xiao-bing li Yuan Yang Yu-Song Xu Guo-Yin Zu School of Metallurgical and Materials Engineering Jiangsu University of Science and Technology(Zhangjiagang)Suzhou215600China School of Materials Science and Engineering Northeastern UniversityShenyang110819China

The microstructural characterization and uniaxial tensile tests of Al/Cu laminated composites were taken to investigate the interface effect and fracture process of the *** electron microscopic graphs before and after tensile test were used to evaluate the fracture *** results show that the fracture surfaces of laminated composites mainly present brittle failure characteristics,accompanied with several dimples on the matrixes and a few tearing on the *** generally initiate from the interfacial interlayer and variously propagate depending on the interfacial *** is found that Cu/Al interface with enhanced bonding strength generally hinders the propagation of interlayer cracks,while the interface with weak bonding delaminates by the cracks propagation through the interfacial *** additional shear stress on the interface between Cu and Al layers due to their different tensile ductilities aggravates the interfacial propagation of *** local plastic deformation of individual matrix layer then occurs after cracks coalesce and failure in the ***,the strong bonding interface and matching properties between individual matrix layers are required to improve the fracture performance of Al/Cu laminated composites.

关键词： Laminated composite Interface Failure analysis Bonding Electron microscopy

Upper bound solutions for supporting pressures of shallow tunnels with nonlinear failure criterion

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Journal of Central South University 2013年第7期20卷 2034-2040页

作者： YANG xiao-li ZHANG Dao-bing WANG Zuo-wei School of Civil Engineering Central South University Changsha 410075 China

linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of almost all types of rocks, A nonlinear Hock-Brown failure criterion is employed to estimate the supporting pressures of shallow tunnels in limit analysis framework. Two failure mechanisms are proposed for calculating the work rate of extemal force and the internal energy dissipation. A tangential line to the nonlinear failure criterion is used to formulate the supporting pressure problem as a nonlinear programming problem. The objective function formulated in this way is minimized with respect to the failure mechanism and the location of tangency point. In order to assess the validity, the supporting pressures for the proposed failure mechanisms are calculated and compared with each other, and the present results are compared with previously published solutions when the nonlinear criterion is reduced to linear criterion. The agreement supports the validity of the proposed failure mechanisms. An experiment is conducted to investigate the influences of the nonlinear criterion on collapse shape and supporting pressures of shallow tunnels.

关键词： shallow tunnel nonlinear criterion limit analysis supporting pressure failure mechanism

On the Construction of p-Harmonic Morphisms and Conformal Actions

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Acta Mathematica Sinica,English Series 2007年第8期23卷 1475-1484页

作者： xiao Huan MO li bing HUANG Yuan Zheng ZHANG School of Mathematical Sciences Peking University Beijing 100871 P. R. China and Department of Applied Mathematics Shanghai University of Finance and EconomicsShanghai 200433 P. R. China

We produce p-harmonic morphisms by conformal foliations and Clifford systems. First, we give a useful criterion for a foliation on an m-dimensional Riemannian manifold locally generated by conformal fields to produce p-harmonic morphisms. By using this criterion we manufacture conformal foliations, with codimension not equal to p, which are locally the fibres of p-harmonic morphisms. Then we give a new approach for the construction of p-harmonic morphisms from R^m／{0} to R^n. By the well-known representation of Clifford algebras, we find an abundance of the new 2/3 （m ＋ 1）-harmonic morphism Ф： R^m／{0} → R^n where m = 2κδ（n - 1）.

关键词： p-harmonic morphism Clifford system homogeneous function conformal field

DOCK8 deficiency with mediastinal lymph node tuberculosis

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World Journal of Pediatrics 2020年第2期16卷 213-214页

作者： lin-Qian Zhang xiao-bing li Yun-Guang Bao Jinhua Hospital of Zhejiang University Jinhua 321300China

A 12-year-old girl presented with a history of unexplained persistent fever,accompanied by paroxysmal dry cough,skin *** patient had a past medical history of recurrent fever,pneumonia(at least four times per year),eczema,accompanied by diarrhea,repeated skin Staphylococcus aureus infection since 6 months of *** examination revealed broad nasal bridge and scoliosis,and chest computed tomography(CT)showed pneumonia,partial bronchiectasis of the right lung,and multiple mediastinal lymph node enlargement with confluence(Fig.1).Laboratory studies demonstrated significantly increased blood eosinophils and serum level of total *** biopsy of the rashes on the buttocks suggested eosinophil infiltration.

关键词： diarrhea tuberculosis fever

NDUFA8 potentially rescues Wolbachia-induced cytoplasmic incompatibility in Laodelphax striatellus

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Insect Science 2023年第6期30卷 1689-1700页

作者： Jie Chen Meng-Ke Wang Qi-Xian Xie xiao-li bing Tong-Pu li xiao-Yue Hong Department of Entomology Nanjing Agricultural UniversityNanjingChina

The endosymbiont Wolbachia manipulates host reproduction by several strategies, one of the most important of which is cytoplasmic incompatibility (CI). CI can be rescued when Wolbachia-infected males mate with females infected with the same Wolbachia strain. However, the potential rescue mechanism of CI in the small brown planthopper Laodelphax striatellus is unclear. In this study, comparative transcriptome analysis was applied to explore the effect of Wolbachia on L. striatellus eggs. A total of 1387 differentially expressed genes were identified. RNA interference of 7 Wolbachia-upregulated key planthopper genes reduced egg reproduction, suggesting that Wolbachia might improve fecundity in L. striatellus by affecting these 7 genes. Suppressing the expression of another upregulated gene, NDUFA8 (encoding NADH dehydrogenase [ubiquinone] 1 α subcomplex subunit 8-like) by RNA interference significantly increased the mortality of early embryos without affecting the number of deposited eggs. Wolbachia infection upregulated the mRNA level of NDUFA8, and dsNDUFA8 treatment of Wolbachia-infected females recreated CI-like symptoms, suggesting that NDUFA8 is associated with the rescue phenotype. Because all L. striatellus populations worldwide are infected with Wolbachia, NDUFA8 is a potential pest control target.

关键词： cytoplasmic incompatibility Laodelphax striatellus NDUFA8 reproduc-tion rescue Wolbachia

Implementing method of optimum front-end conditioner based on Butterworth filter

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Nuclear Science and Techniques 2006年第4期17卷 232-236页

作者： ZHANG Ruan-Yu LUO xiao-bing li Tai-Hua Key Laboratory for Radiation Physics and Technology of Ministry of Education of China Physics Science and Technology College of Sichuan University Chengdu 610064 China

The front-end conditioner is an essential part of digital systems of nuclear spectrometer, which functions in two ways: (1) prevents saturation of the subsequent ADC; (2) limits the bandwidth of frequency to realize anti-aliasing. To realize the above-mentioned functions, an optimum front-end conditioner for a resistive feedback charge-sensitive preamplifier is designed. In the conditioner, the pole-zero compensation (P/Z compensation) tech- nique was used to effectively filter signals from the preamplifier. The Butterworth filter was improved after the pole-zero position was optimally set up to shape the wave of output, which tallied with the whole system. The front-end conditioner can resolve the aberration of waveform of nuclear signals in a regular Butterworth filter. Com- pared with the traditional triple-pole filtering circuitry, the circuitry of this conditioner is more compact and flexible. Moreover, its output waveform is more symmetrical and the signal-to-noise ratio (SNR) is higher. The improvement in the resolution of spectrometer is also significant.

关键词：数字式核子能谱仪极点-零点补偿巴特沃斯滤波器前端调节器