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Tuning the Fermi level in Bi2Se3 bulk materials and transport devices

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Frontiers of physics 2012年第2期7卷 160-164页

作者： zhi-yong wang (1) Peng Wei (1) Jing Shi (1) University of California Department of Physics & Astronomy Riverside USA (GRID:grid.266097.c) (ISNI:***)

Bi2Se3 has been predicted to be a three-dimensional （3D） topological insulator （TI） with Dirac fermions residing on the two-dimensional （2D） surface. Unique transport properties such as high carrier mobility due to the suppressed backscattering are expected for the Dirac fermions. In order to eliminate the contribution of the bulk carriers, therefore, to place the Fermi level in the band gap of Bi2Se3, we first introduce various amounts of Ca dopants into the crystal to realize the bulk insulating state. Then by avoiding uncontrolled heating and electron beam irradiation in the nanofabrication process, we maintain the insulating state in thin devices. By sweeping the gate voltage, we have observed a conductivity minimum that is expected for the Dirac fermions in the band gap of 3D TIs.

关键词： topological insulators Bi2Se3 transport properties nano-devices

Progress in the beam commissioning of separated function RFQ accelerator

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Science China(Physics,Mechanics & Astronomy) 2011年第S2期54卷 222-224页

作者： MingLei Kang (1) YuanRong Lu (1) zhi wang (1) Kun Zhu (1) XueQing Yan (1) zhiYu Guo (1) ShuLi Gao (1) ShiXiang Peng (1) Ao Liu (2) JiaXun Fang (1) JiaEr Chen (1) 1. State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China2. Department of Physics Indiana University Bloomington IN 47405 USA

Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating efficiency than the conventional RFQ accelerator. The first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O+ beam from 1.03 MeV to 1.64 MeV. Based on accomplishment of low power measurement and high power test, the beam commissioning was carried out to verify its feasibility. The measured energy gain per cell of SFRFQ is 45 keV, which is about 60% higher than that of Peking University Integral Split Ring (ISR) RFQ.

关键词： separated function RFQ beam commissioning energy spectrum

Preparation of Polyclonal Antibodies of Rubisco Large and Small Subunits and Their Application in the Functional Analysis of the Genes

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 644-648页

作者： Peng-Da MA1, Tian-Cheng LU1, Xiao-Fu ZHOU1,2, Xiao-Juan ZHU1, and Xing-zhi wang1*1The Institute of Genetics and Cytology, Northeast Normal University, Changchun 130024, China 2The Institute of Gene Technology, Jilin Normal University, Siping 136000, China The Institute of Genetics and Cytology Northeast Normal University The Institute of Gene Technology Jilin Normal University

Spinach Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase) large (rbcL) and small (rbcS) subunits were separated by SDS-PAGE, and protein amount and purity were determined by Bradford assay. Polyclonal antibodies against rbcL and rbcS subunit were generated in female BALB/c mice and had no cross-reaction with each other. A total of 81 μg antigens were used and 0.3 ml anti-sera with titer of 1:5000 were yielded. The antibodies were also applicable to study rbcL and rbcS in tobacco plant Nicotiana benthamiana. Potato virus X vector pGR107 induced silencing of rbcS gene by Agrobacterium in Nicotiana benthamiana was performed. The expression level of rbcL and rbcS was lower in rbcS silenced plants than that in control plants as detected by the corresponding antibodies. This implied that the expression of rbcL was regulated by rbcS.

关键词： ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) rbcL rbcS polyclonal antibody virus-induced gene silencing (VIGS)

Determination of Optimal Recrystallization Annealing Temperature of Nb-Ti Microalloyed High Strength IF Steel

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Journal of Iron and Steel Research International 2011年第S1期18卷 388-392页

作者： wang Min-li 1,XIAO Li 2,ZHENG zhi-wang 1,ZHANG Gong-ting 1 (1.PanGang Group Research Institute Co Ltd.,Chengdu 611731,Sichuan,China 2.PanGang Group Xichang company,Xichang 615041,Sichuan,China) PanGang Grp Res Inst Co Ltd Chengdu 611731 Sichuan Peoples R China PanGang Grp Xichang Co Xichang 615041 Sichuan Peoples R China

The Nb-Ti microalloyed high strength IF steel sheet was used to study the effect of annealing temperature on the microstructures,mechanical properties and *** experimental results show that experimental steel is incomplete recrystallization at 750℃ annealing,but complete recrystallization from 780℃ to 870℃ under experimental *** the annealing temperature was increased,the yield strength and tensile strength would gradually reduce,the plastic strain ratio and yield point elongation would gradually *** yield strength,tensile strength,elongation,the plastic strain ratio and the strain hardening exponent were approximate 300MPa,410MPa,36.5%,1.7 and 0.22 respectively under annealing temperature 810℃ to 840℃.When the annealing temperature was increased,the α-textures and γ-textures were gradually weakened,and the α-textures have a trend to {111} ***,the suggestion of the optimal recrystallization annealing temperature is about 810℃ to 840℃ in industrial production.

关键词： Nb-Ti microalloyed high strength IF steel salt-bath annealing recrystallization annealing temperature textures

Self-cementing Mechanism of CFBC Coal Ashes at Early Ages

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Journal of Wuhan University of Technology(Materials Science) 2008年第3期23卷 338-341页

作者：宋远明钱觉时 School of Materials Science and Engineering Chongqing University

The self-cementing mechanism at early ages of circulating fluidized bed combustion （CFBC） coal ashes was studied by X-ray diffraction （XRD）, infrared （IR） spectroscopy and chemical method. The results indicate that the amorphous phase is predominant in CFBC coal ashes. The polymerization degree of [SiO4] and [AlO6] of CFBC desulphurization coal ashes is lower than that of those without desulphurization. The contents of the components with fast hydration rate of CFBC desulphurization coal ashes are significantly greater than those of the ashes without desulphurization. This work confirms that the amorphous minerals with high chemical activity are the main causes of the self-cementing property of CFBC desulphurization coal ashes at early ages.

关键词： CFBC ashes self-cementing property mechanism hydration microstructure

Source of blood supply of liver cavernous hemangioma and sclerosis and embolization treatment

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World Journal of Gastroenterology 1997年第3期3卷 19-21页

作者： LI Gou Wei 1, ZHAO Zhong Rong 2, LI Bao Sheng 1, LIU Xiao Gong 1, wang zhi Liang 1 and LIU Qing Feng 1

AIM To investigate the source of blood supply of carvenous hemangioma of liver (CHL) and provide a feasibile treatment for CHL via hepatic artery. METHODS Ⅰ. Origin of blood supply of CHL: portovenography, hepatic arteriography and portal vein staining were performed in 5 patients. Two casts of hepatic blood vessels from resected specimen were observed. Ⅱ. Clinical data: Among 75 patients (30 males, 45 females, aged 25～57 years with a mean of 37 4). 56 were of solitary type (44 on the right lobe, 12 on the left with 4 having intraparenchymatoma) and 19 were of multiple type (9 on the right, 2 the left, 8 whole liver). Twenty two patients were treated by sclerosis, 50 by embolization via hepatic artery and 3 were excised. RESULTS In 5 cases with portography, the contrast medium did not enter the tumor, the tumor appeared as low denty area and the intrahepatic branches of portal vein were pushed aside. In 5 cases with portal vein staining, the normal liver parenchyma was stained deep blue, and the tumor was not stained. The tumor area appeared as a round vacant cavity in 2 specimen casts. In 72 patients treated with sclerosis a or embolization via hepatic artery or through interventional method, the tumors diminished by 10%～30% in diameter and no tumors grew larger. CONCLUSION The blood supply of CHL originates from the hepatic artery. Tumors treated with sclerosis and emblization decreased in size or got fiberized.

关键词： Liver neoplasms/blood supply liver neoplasms/therapy hemangioma, cavernous/therapy embolization, therapeutic sclerotherapy

A cross-sectional study on HGV infection in a rural population

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World Journal of Gastroenterology 1998年第6期4卷 34-37页

作者： LING Bin Hua 1, ZHUANG Hui 1, CUI Yi Hui 1, AN Wen Feng 1, LI zhi Jie 1, wang Shu Ping 2 and ZHU Wan Fu 2

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关键词： GB virus C hepatitis G virus non A, non B hepatitis hepatitis B virus hepatitis C virus enzyme linked immunoassy polymerase chain reaction

Effect of Nb on the Mechanical Properties of Ti/Al_2O_3 Composite

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 30-32,36页

作者：王志 School of Materials Science and Engineering Ji'nan University Jinan 250022China State Key Laboratory of Advanced Technology for Materials Synthesis and Proces sing Wuhan University of Techology Wuhan 430070China

Ti/Al 2O 3 composite with improved mechanical properties was synthesized by th e spark plasma sintering. The effect of Nb on the microstructure of the composit e was analyzed by TEM, SEM and so on. The experimental results indicate that the bending strength, fracture toughness, micro-hardness and relative density of t he composite are 897.29MPa, 17.38MPa·m 1/2, 17.13GPa and 99.24% respec tively when adding 1.5vol%Nb. The bending strength is improved by reason of form ing dislocation ring and transfering fracture mode from intergranular to mixture fracture of intergranular and transgranular. The crack propagating is mainly th e deflection bridging. It indicates a reduction of crack driving force and an in crease in crack growth resistance,which results in toughness enhanced.

关键词： spark plasma sintering Ti/Al 2O 3 composite niobium mechanical properti es

DYNAMIC CHANGES OF THE WETLAND AND ITS DRIVING FORCES IN FUJIN REGION IN SANJIANG PLAIN,CHINA

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湿地科学 2005年第3期3卷 176-182页

作者： wang zhi-Qiang~1,2, CHEN Ming~1,2,wang Dan-Dan~1,2 , ZHANG Bai~1,ZHANG Shu-Qing~1(1. Northeast Institute of Geography and Agricultural Ecology, the Chinese Academy of Sciences,Changchun Jilin 130012, China 2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China ) Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China Graduate School of Chinese Academy of Sciences Beijing 100039China Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China

Wetland is a kind of key natural resources. However, the wetlands have been shrinking rapidly in Sangjiang Plain and its functions have been degrading. These all hold back the sustainable development of human communities, and lead to great change in the land use /cover (LUCC), consequently caused global changes in climate, water cycling, etc.. Taken Fujin region as a case study, spatial and temporal dynamic processes of wetland and its driving forces were analyzed from 1954 to 2000 in this paper. It showed that the wetlands had been reduced from 52×104 ha to 11×104 ha in areas during the nearly 50 years . The percentage of wetland areas reduced from 61.27% to 12.39%. On the other hand, cultivated land increased from 22×104 ha to 60×104 ha in areas. The percentage of the areas increased from 25.31% to 70.45%. Further quantitative analysis of the wetland landscape conversion characteristics and the correlation analysis between the change of wetland areas and population increase were made. The results showed that 40×104 ha wetlands had been converted to cultivated land within half of a century; the correlation between the rate of wetland loss and that of population increased is nearly -0.922. So it was concluded that the main driving force of wetland shrinkage in Fujin region was the colonization of human being.

关键词：湿地动态变化三江平原生态系统生态环境