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Effects of chemical coating with Ni on electrochemical properties of Mg_2Ni hydrogen storage alloys

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Rare Metals 2007年第6期26卷 611-616页

作者： TANG Yougen SHEN jianbin xu Yijun JIANG Jinzhi Chemistry and Chemical Engineering School Central South University Changsha 410083 China

The effects of nickel coating on the electrochemical properties of Mg2Ni hydrogen storage alloys are presented in this paper. X-ray diffraction （XRD） and scanning electron microscope （SEM） techniques were employed to examine the crystal structure and surface morphologies of the bare and Ni-coated Mg2Ni alloys. The electrochemical properties of alloys were characterized by cyclic voltammetry （CV） and dectrochemical impedance spectroscopy （EIS）. The results showed that Ni coating not only decreased the charge transfer resistance, but also decreased the H atom diffusion resistance for Mg2Ni alloys. It was also found that Ni coating effectively improved the discharge capacity, but decreased the cycling performance of the as-synthesized Ni-coated MgzNi alloys. The discharge current has a great impact on the cycling perform- ance of the as-synthesized Ni-coated Mg2Ni alloys.

关键词： hydrogen storage alloys chemical coating cyclic voltammetry electrochemical impedance spectroscopy

Study of the Mineralization Process of granular apatites in Weng'an Baidou Phosphate Deposit Using Microbeam Analyses

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Acta Geologica Sinica(English Edition) 2017年第S1期91卷 293-295页

作者： YANGH Haiying XIAO Jiafei LI Yantao xu jianbin University of Chinese Academy of Sciences Institute of Geochemistry Chinese Academy of Sciences

1 Introduction Studies of marine sedimentary phosphate rock have lasted decades,scholars proposed some standpoints about mineralization,however,the genesis of mineral deposits remains to be a controversial question(She et al.,2013).There are many viewpoints of mineralization about the Doushantuo phosphorites,Central Guizhou,including biological mineralization(Mi et al.,2010;Shi et al.,2005),

关键词： In EPMA Study of the Mineralization Process of granular apatites in Weng’an Baidou Phosphate Deposit Using Microbeam Analyses

Realization of vertical and lateral van der Waals heterojunctions using two-dimensional layered organic semiconductors

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Nano Research 2017年第4期10卷 1336-1344页

作者： Yuhan Zhang Zhongzhong Luo Fengrui Hu Haiyan Nan Xiaoyong Wang Zhenhua Ni jianbin xu Yi Shi Xinran Wang National Laboratory of Solid State Microstructures School of Electronic Science and Engineering and Collaborative Innovation Cen ter of Advanced Microstructures Nanjing University Nanjing 210093 China School of Physics Nanjing University Nanjing 210093 China Department of Physics Southeast University Nanjing 211189 China Department of Electronic Engineering and Materials Science and Technology Research Center The Chinese University ofHong Kong Hong Kong SAR China

Van der Waals （vdW） heterojunctions based on two-dimensional （2D） atomic crystals have been extensively studied in recent years. Herein, we show that both vertical and lateral vdW heterojunctions can be realized with layered molecular crystals using a two-step physical vapor transport （PVT） process. Both types of heterojunctions show clean and sharp interfaces without phase mixing under atomic force microscopy （AFM）. They also exhibit a strong interfacial built-in electric field similar to that of their inorganic counterparts. These heterojunctions have greater potential for device applications than individual materials. The lateral heterojunction （LHJ） devices show rectifying characteristics due to the asymmetric energy barrier for holes at the interface, while the vertical heterojunction （VHJ） devices behave like metal-insulator-semiconductor tunnel junctions, with pronounced negative differential conductance （NDC）. Our work extends the concept of vdW heterojunctions to molecular materials, which can be generalized to other layered organic semiconductors （OSCs） to obtain new device functionalities.

关键词： two-dimensional heterojunctions organic semiconductor van der Waals epitaxy

Space-time analysis of the changing patterns of population pressure on the ecological environment in China

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Chinese Journal of Population,Resources and Environment 2015年第4期13卷 341-348页

作者： Dongqi Sun Jinliang Jiang jianbin xu Liang Zhou Yi Hu Institute of Geographic Sciences and Natural Resources Research CAS School of Geographic and Oceanographic Sciences Nanjing University College of Geography and Planning Ludong University Urban-Rural Planning Administration Center Ministry of Housing and Urban-Rural Development

This paper examines the temporal change and spatial variation of population pressure on the ecological environment in *** have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and *** a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment *** conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to *** on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality.

关键词： Chinese population eco-environment eco-environmental pressure changing trend space-time analysis

OBSERVATION OF LEAKY SAW AND OTHER ACOUSTIC MODES ON 49°Y-ROTATED LiNbO3 BY OPTICAL DIFFRACTION METHOD

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Chinese Physics Letters 1988年第1期5卷 21-24页

作者： WU Wenqiu xu jianbin ZHANG Shuyi Institute'of Acoustics Nanjing UniversityNanjing

The propagation properties of *** and SAW as well as acoustic bulk waves on the substrate of 49° Y-rotated LiNbO_(3) excited by IDT are investigated by Schaefer-Bergmann diffraction technique and electrical method・The inverse phase velocity curves in the propagation plane are obtained both experimentally and *** existence of LSAW in some directions on the substrate has been verified.

关键词： propagation excited directions

Phosphorite generative processes around the Precambrian-Cambrian boundary in South China: An integrated study of Mo and phosphate O isotopic compositions

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Geoscience Frontiers 2021年第5期12卷 237-263页

作者： Haiying Yang Jiafei Xiao Yong Xia Zhuojun Xie Qinping Tan jianbin xu Shan He Shengwei Wu Xiqiang Liu Xingxiang Gong State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Earth Sciences Yunnan UniversityKunming650500China School of Qilu Transportation Shandong UniversityJinan 250061China University of Chinese Academy of Sciences Beijing 101408China Reserve Bureau of Land and Mineral Resources of Guizhou Province Guiyang 550081China

Large phosphorite deposits in Central Guizhou,China,were formed around the Precambrian/Cambrian boundary(PC/C),including the Ediacaran(Doushantuo stage)and early Cambrian(Gezhongwu stage).Among them,Gezhongwu phosphorite from Zhijin are enriched in rare earth elements(REE)plus yttrium(REY),reaching 3.503 million *** phosphorites have attracted great attention,the specific sources P and REY remained *** determine the P and REY sources and establish a phosphogenic model of PC/C phosphorite,we present an integrated dataset of Mo and phosphate O isotopes for the first time,along with carbonate C and O isotopes,geology,petrology,and *** all samples,d18Op,Y/Ho,and Zr/Hf decreased from the Ediacaran to the early Cambrian,indicating increased terrigenous weathering fluxes while decreased upwelling water ***,terrigenous weathering delivery significantly elevated marine REY concentrations in the Cambrian in *** Ceanom and d98/95Mo suggest that seawater was oxidized in the later Ediacaran and became entirely oxic in the early *** positive feedback between oxygen levels in atmosphere and primary productivity caused progressive oxygenation in ocean-atmosphere system and enable phosphorites to be formed by different *** show that the Lower Doushantuo consist of abiotic intraclasts and exhibited“seawaterlike”REY types,indicating abiological and mechanical reworking *** Upper Doushantuo and Gezhongwu Formation contained mainly microbial debris and abiogenic intraclasts,and exhibit “hat-shaped”REY plots,suggesting microbially mediated *** on this data set,we developed a phosphogenic model illustrating formation of these two phosphorite deposits,wherein the Lower Doushantuo phosphorite formed through the reworking of pre-existing phosphatic sediments in anoxic and abiotic ocean,whereas the Upper Doushantuo and Gezhongwu phosphorite formed via microbial metabolisms in oxic and bio

关键词： Doushantuo formation Gezhongwu formation Phosphorite Ore-forming material origin Phosphate O isotope Mo isotope

The Influence of L1 Mental Lexicon on L2 Mental Lexicon

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Sino-US English Teaching 2006年第9期3卷 21-24页

作者： Ying xu jianbin Huang Zhejiang University

This paper deals with the influence of L1 （first Language） mental lexicon on L2 （second Language） mental lexicon with Chinese subjects. It proves two possibilities： the response types in L1 and L2 of a single individual may be similar, and the dominant language （mostly L1） and the L2 may interfere with each other＇s vocabulary depth and breadth. The result is of great significance for Chinese learners of English.

关键词： L1 mental lexicon L2 mental lexicon vocabulary acquisition

CircZFR promotes colorectal cancer progression via stabilizing BCLAF1 and regulating the miR-3127-5p/RTKN2 axis

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Science China(Life Sciences) 2024年第9期67卷 1881-1898页

作者： Jiaxin Chen Huijuan Wang jianbin xu Engeng Chen Qing Meng Jiawei Wang Haoyi Xiang Wei Zhou Ge Shan Zhenyu Ju Zhangfa Song Department of Colorectal Surgery Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China Key Laboratory of Biological Treatment of Zhejiang Province Hangzhou 310016China Department of Pulmonary and Critical Care Medicine Regional medical center for National Institute of Respiratory DiseaseSir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative MedicineJinan UniversityGuangzhou 510632China Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China Department of Orthopedic Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310009China

Aberrant expression of circular RNAs(circ RNAs)is frequently linked to colorectal cancer(CRC).Here,we identified circ ZFR as a promising biomarker for CRC diagnosis and *** ZFR was upregulated in CRC tissues and serum exosomes and its level was linked to cancer incidence,advanced-stages,and *** both in vitro and in vivo settings,circ ZFR promoted the growth and spread while suppressing apoptosis of *** with circ ZFR overexpression promoted the proliferation and migration of cocultured CRC ***,epithelial splicing regulatory protein 1(ESRP1)in CRC cells may enhance the production of circ ***2-associated transcription factor 1(BCLAF1)bound to circ ZFR,which prevented its ubiquitinated ***,circ ZFR sponged mi R-3127-5p to boost rhotekin 2(RTKN2)*** TCP1-CD-QDs nanocarrier was able to carry and deliver circ ZFR si RNA(si-circ ZFR)to the vasculature of CRC tissues and cells,which inhibited the growth of tumors in patient-derived xenograft(PDX)*** together,our results show that circ ZFR is an oncogenic circ RNA,which promotes the development and spread of CRC in a BCLAF1 and mi R-3127-5p-dependent *** ZFR is a possible serum biopsy marker for the diagnosis and a desirable target for further treatment of CRC.

关键词： circZFR exosome ESRP1 BCLAF1 miR-3127-5p nanoparticle(NP)

Expression of hypoxia-inducible factor-1 a and vascular endothelial growth factor in the retina of diabetic rats

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Expression of hypoxia-inducible factor-1 a and vascular endo...