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Tetrapartite entanglem ent features of W-C lass state in uniform acceleration

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Frontiers of physics 2020年第1期15卷 1-8页

作者： Qian dong Ariadna J.Torres-Arenas Guo-Hua Sun shi-Hai dong Laboratorio de Informacion Cuantica CIDETECInstituto Politecnico NacionalUPALMCDMX 07700Mexico Catedratica CONACyT Centro de Investigacion en ComputacionInstituto Politecnico NacionalUPALMCDMX 07738Mexico

Using the single-mode approximatiou,we first calculate entanglement measures such as negativity(1-3 and 11 tangles)and von Neumann entropy for a tetrapartite W-Class system in noninertial fiarne and then anal^e the whole entanglement measures,the residualπ4 and geometricП4 average of *** that the difference betweenπ4 andП4 is very small or disappears with the increasing accelerated *** entanglement properties are compared among the different cases from oue accelerated observer to four accelerated *** results show that there still exists entanglement for the complete system even when accelemtion r tends to *** degree of entanglement is disappeared for the 1-1 tangle case when the acceleration r>*** reexamine the Unriih effect in noninertiai *** is shown that the entanglement system in which only one qubit is accelerated is more robust than those eutangled systems in whicli two or three or four qubits are *** is also found that the von Neumann entropy S of the total system always increases with the increasing accelerated observers,but the Sκξand Sκζδwith two and three involved noniuertial qubits first increases and then decreases with the acceleration parameter r,but they are equal to constants 1 and 0.811278 respectively for zero involved iioniiiertial qubit.

关键词： tetrapartite W-Class state entanglement Dirac field noninertiai frames

Wear behavior of high velocity arc sprayed 3Cr13 steel coating in oil containing sand

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中国有色金属学会会刊：英文版 2004年第z1期14卷 370-373页

作者： DU Ling-zhong XU Bin-shi dong shi-yun YANG Hua WU Yi-xiong College of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200030 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 National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China College of Materials Science and Engineering Shanghai Jiaotong UniversityShanghai 200030 China

To improve the wear resistance of the machine components serving in desert areas, the 3Cr13 stainless steel coating was produced by the high velocity arc spraying technique. The microstructure and phase constitute of the coating were analyzed by SEM and XRD. The effects of sand content on the friction and wear behaviors of the coating under the lubrication of oil containing sand were investigated on a ball-on-disk tester. SEM was used to reveal the wear mechanisms of the coating. The results show that the wear volume increases with increasing the sand content in the oil, and the sprayed coating exhibits better triobological properties compared with the 1045 steel. The predominant wear mechanisms of the sprayed coating are micro-cutting, brittle fracture and delamination.

关键词： high velocity arc spraying coating friction and wear behavior oil sand

Influence of heat treatment on microstructures and micro-hardness of n-SiO2/Ni composite coating

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中国有色金属学会会刊:英文版 2004年第z1期14卷 111-114页

作者： XU Bin-shi WANG Hai-dou dong shi-yun JIANG Bin TU Wei-yi National Key Laboratory for remanufacturing Academy of Armored Force Engineering Beijing 100072 China

The n-SiO2/Ni composite electro-brush plating coating was prepared on the 1045 steel substrate. SEM and TEM were utilized to analyze the surface and cross-section morphologies or the microstructures of the composite coating before and after heat treatment, as well as a micro-hardness tester was used to measure the micro-hardness before and after heat treatment. The results show that the entrance of nano SiO2 particles into composite coating makes the micro-hardness higher. After heat treatment, due to the obstruction to growth of Ni crystals from nano particles, the composite coating still possesses a higher micro-hardness than that of common Ni-base coating.

关键词： nano SiO2 particles electro-brush plating composite coating heat treatment microstructures microhardness

Formation and capturing of nanoparticles in Cu-1wt.%Fe alloy melt during directional solidification process

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Journal of Iron and Steel Research International 2017年第4期24卷 411-415页

作者： Tao Wang Xiao-hua Chen Guo-dong shi Chang-rong Li Zi-dong Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional *** of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain *** show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase *** that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.

关键词： Single crystal Copper alloy Nanoparticle Coherent interface Brownian motion

Analysis on phase selection and microstructure evolution in directionally solidified Zn-Al-Mg-Ce alloy

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China Foundry 2023年第4期20卷 347-355页

作者： Ji-peng Li De-gao Qiao shi-wen dong Peng Peng Xian-tao Yan Xu-dong Zhang Gansu Jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735199GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China School of Physics and Electronic Information Engineering Qinghai Normal UniversityXining 810016QinghaiChina

In the process of hot-dip Zn-Al-Mg alloy coating,the plating solution dissipates heat in the direction perpendicular to the steel plate,which is considered to be a process of directional *** understand the relationship between microstructure and cooling rate of Zn-Al-Mg alloys,both the phase constitution and microstructure characteristic length scales of Zn-9.5Al-3Mg-0.01Ce(wt.%)alloy were investigated by the directional solidification experiments at different growth velocities(V=40,80,160,250μm·s^(-1)).The experimental results show that the microstructure of directionally solidified Zn-9.5Al-3Mg-0.01Ce alloy is composed of primary Al dendrites and(Zn-Al-Mg2Zn11)ternary eutectics at the growth velocities ranging from 40 to 250μm·s^(-1).The primary Al dendrites are aligned regularly along the growth direction,accompanied with obvious secondary *** relationship between the microstructure length scale and the thermal parameters of solidification is obtained:λ1=374.66V-0.383,andλ2=167.5V-0.563(λ1is the primary dendrite arm spacing,andλ2 is the secondary dendrit arm spacing).In addition,through the interface response function(IRF)and the nucleation and constitutional undercooling(NCU),the phase selection of Zn-9.5Al-3Mg-0.01Ce is obtained:(Zn+Al+Mg2Zn11)ternary eutectics in the Zn-9.5Al-3Mg-0.01Ce alloy will be replaced by ternary eutectics(Zn+Al+MgZn2)when the growth rate is lower than 7.53μm·s^(-1).

关键词： Zn-Al-Mg alloy directional solidification microstructure length scale phase selection

Chemical constituents from Vernonia bockiana

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Chinese Journal of Natural Medicines 2019年第12期17卷 924-927页

作者： dong shi-Hui WU Yan YUE Jian-Min State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

A new sesquiterpenoid and two pregnane steroids,named vernobockolide C(1)and vernobockones A and B(2 and 3),respevtively,along with a known sesquiterpenoid,7,10-epoxy-11-hydroxy-bisabol-2-en-15-al,were isolated from the aerial part of Vernonia *** structures were elucidated on the basis of extensive spectroscopic data analysis,especially 2 D NMR(HSQC,HMBC,and ROESY).This study further expands the chemical space of this underexplored species.

关键词： Vernonia bockiana Sesquiterpenoid Steroid

Stroke-induced immunosuppression and poststroke infection

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Stroke & Vascular Neurology 2018年第1期3卷 34-41页

作者： Kaibin shi Kristofer Wood Fu-dong shi Xiaoying Wang Qiang Liu Departments of Neurology Tianjin Neurological InstituteTianjin Medical University General HospitalTianjinChina Departments of Neurology Barrow Neurological InstituteSt.Joseph’s Hospital and Medical CenterPhoenixArizonaUSA Departments of Neurology and Radiology Neuroprotection Research LaboratoryMassachusetts General HospitalNeuroscience ProgramHarvard Medical SchoolBostonMassachusettsUSA

Infections occur commonly after stroke and are strongly associated with an unfavourable functional outcome of these *** for effective management of poststroke infection remain scarce,presenting an urgent need for preventive anti-infection strategies for patients who have suffered a *** evidence indicates that stroke impairs systemic immune responses and increases the susceptibility to infections,suggesting that the modification of impaired immune defence could be *** this review,we summarised previous attempts to prevent poststroke infections using prophylactic antibiotics and the current understanding of stroke-induced *** elucidation of the immune mechanisms of stroke will pave the way to tailored design of new treatment to combat poststroke infection via modifying the immune system.

关键词： infection impaired stroke

Composite penalty method of a low order anisotropic nonconforming finite element for the Stokes problem

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Applied Mathematics(A Journal of Chinese Universities) 2013年第1期28卷 49-56页

作者： WU Jing-zhu XING Xiu-zhi shi dong-yang Department of Mathematics Zhoukou Normal University Department of Mathematics Zhengzhou University

Composite penalty method of a low order anisotropic nonconforming quadrilateral finite element for the Stokes problem is presented. This method with a large penalty parameter can achieve the same accuracy as the stand method with a small penalty parameter and the convergence rate of this method is two times as that of the standard method under the condition of the same order penalty parameter. The superconvergence for velocity is established as well. The results of this paper are also valid to the most of the known nonconforming finite element methods.

关键词： Stokes problem composite penalty method anisotropic mesh.

Influence of Arbuscular Mycorrhizal Fungi on Growth, Mineral Nutrition and Chlorogenic Acid Content of Lonicera confusa Seedlings Under Field Conditions

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Pedosphere 2013年第3期23卷 333-339页

作者： shi An-dong LI Qian HUANG Jian-Guo YUAN Ling College of Resources and Environment Southwest University

Lonicera confusa, a traditional Chinese medicine herb for treating cold, flu, acute fever, and so forth, is often grown artificially in acidic soils and suffers from phosphorus (P) deficiency. A five-year field experiment was carried out to study the colonization rate, growth, nutrition, and chlorogenic acid content of Lonicera confusa seedlings inoculated with arbuscular mycorrhizal (AM) fungi, Glomus etunicatum and Glomus intraradices. Before transplanting into a field, both AM-inoculated and uninoculated control plants were cultured in nursery beds. In the plants inoculated with the AM fungi, the colonization rate decreased linearly with time and a greater decrease was observed in the plants inoculated with G. intraradices than with G. etunicatum, while the AM colonization increased from 0% to 12.1% in the uninoculated control plants 5 years after transplanting. Plant height, crown diameter, number of new branches, and flower yield increased significantly by AM inoculation as compared to the uninoculated control. Phosphorus concentrations in leaves and flowers increased, and plant uptake of nutrients, e.g., nitrogen (N), P, and potassium (K), was also enhanced significantly by AM inoculation. The Lonicera confusa seedlings had a better response to inoculation of G. intraradices than G. etunicatum in both growth and chlorogenic acid content in flowers. In contrast, both plant P uptake and P concentrations in leaves and flowers were similar between two fungal inoculations. The positive responses of Lonicera confusa to AM inoculation in growth, nutrient uptake, flowering, and chlorogenic acid content in flowers suggested that AM inoculation in nursery beds could promote the plant growth and increase chlorogenic acid content in flowers of Lonicera confusa when grown on acidic and P-deficient soils.

关键词： Glomus colonization rate nursery beds nutrient uptake P deficiency