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Selective Reduction of 7-Demethylsinomenine

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Chemical Research in Chinese Universities 2008年第5期24卷 557-560页

作者： LI Yu-feng bu Qing-min QIAN yi PAN yi LI Jian-xin HUANG Le-qun ZHU Hong-jun School of Science Nanjing University of Technology Nanjing 210009 P. R. China Department of Chemistry School of Chemistry and Chemical Engineering School of Medicine Nanjing University Nanjing 210093 P. R. China

Several borohydride reagents： sodium borohydride, sodium cyanoborohydride, soudium acetoxyborohydride and soudium triacetoxyborohydride were screened, respectively, for the reduction of 7-demethylsinomenine, which was an α,β-dicarbonyl compound derived from sinomenine. Highly regio-and stereo-selectivity was acquired when sodium cyanoborohydride or NaBH（OAc）3 was used. The product was structurally confirmed as 7R configuration by NMR, X-ray crystal diffraction analysis. Some preliminary discussion was also made on the mechanism of the selective reduction.

关键词： 7-Demethylsinomenine Regioselective reduction Stereoselective reduction Borohydride reagents

Electrochemical Probe of Hydroxylation of 4-Nitro-phenol by Cytochrome C with Hydrogen Peroxide

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Chemical Research in Chinese Universities 1998年第2期14卷 45-51页

作者： ZHU yi-min WANG Jin-cheng LI Jing-hong DONG Shao-jun bu Feng-quan Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022 Norma n Bethune Univer sity of Medica l Science Cha ngchun130023

bu Fengquan(Norman Bethune University of Medical Science, Changchun, 130023)(Received Dec. 2, 1996) The reaction of hydrogen peroxide with cytochrome c makes them coupled to lead to the hydroxylation of 4-nitrophenol. In situ electrochemical probe was used to detect the hydroxylation of 4-nitrophenol, which can avoid the tedious extraction procedure, the loss of the active species and the interference of some colored substances in the detection of 4-nitrocatechol by spectroscopic method. The hydroxyl radical scavengers mannitol and sodium benzoate did not eliminate hydroxylation, but the inhibitory effect of uric acid on the hydroxylation lead to the formation of the ferryl species of the protein during the reaction. These studies suggest that the electrochemical probe might efficiently detect the trace 4-nitrocatechol from the onset of the hydroxylation reaction and thus provides a more sensitive tool.

关键词： Hydrogen peroxide Hydroxylation of 4-nitrophenol Cytochrome c

The Origin and Preservation of Suspended Barites near the 90°E Ridge in the Northeastern Indian Ocean

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Journal of Ocean University of China 2023年第1期22卷 88-98页

作者： bu Xuejiao LIU Ming DING yi YANG Yadi HUANG Mu SUN Xiaoxia FAN Dejiang YANG Zuosheng College of Marine Geosciences Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences and Technology MOEOcean University of ChinaQingdao 266100China Shandong Provincial No.4 Institute of Geological and Mineral Survey Weifang 261021China Key Laboratory of Marine Geology and Metallogeny Ministry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China

Suspended particulate barite crystals were detected in the water columns at four different stations near the 90°E ridge in the Indian *** distinct morphological types of marine barites were distinguished:euhedral-subhedral crystals,oval or round crystals,rhombic crystals,and irregular *** barite crystals in the study area are typically fine,with a dominant size of 1–3μ*** vertical distribution of barites is significantly affected by the formation and sedimentation *** begin to appear at a depth of 30 m and are formed primarily from the surface to the depth of 2000m with a concentration peak at the depth of 200m,where particles are coarser than those in the other *** barites begin to settle and dissolve once formed in the water column,resulting in finer barite particles and lower particle *** formation of barite crystals is related to biological processes associated with the decomposition of barium-rich skeletons in the microenvironment of decaying organic matter that is affected by the primary productivity and dissolved oxygen content in the water *** dissolving process of barite crystals showed similar variation with the concentration of dissolved barium in ocean water,and the substitution of strontium for barite in crystals promotes the selective dissolution of barite and exerts an important impact on its *** is approximately 33%of barites in the amount and 22%in the concentration to settle to the bottom of the water column compared to that observed in the main barite formation zone.

关键词： marine barite Indian Ocean origin and sedimentation process dissolution and preservation

Simulation of Cobalt-Rich Crust’s Crushing Process Based on ANSYS

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Journal of China University of Mining and Technology 2006年第1期16卷 28-32页

作者： XIA yi-min MA Zhi-guo bu ying-yong ZHAO Hai-ming College of Mechanical and electronic Engineering Central South University Changsha Hunan 410083 China

It is a great concern in international oceanology to mine cobalt-rich crust. At present, spiral mining head is regarded as the best crushing scheme. Based on the dynamic model of spiral mining head, the of cobalt crust’s crushing process was simulated with the ANSYS software. The material model of Johnson and Cook Plasticity, maximal princi- pal stress failure criterion, and eroding contact arithmetic were selected. At the same time, the influence of cutting depth, feed speed, rotational speed of mining head on torque and force subjected by mining head was taken into account. At last a computer simulation model of crushing process of cobalt crust was established. By analyzing simulation results, the relationships among these controllable process parameters, torque and force can be obtained, which will provide a technical reference for practical mining system.

关键词： cobalt-rich crust mining head simulation finite element ANSYS

Construction of hierarchical photocatalysts by growing ZnIn_(2)S_(4) nanosheets on Prussian blue analogue-derived bimetallic sulfides for solar co-production of H_(2) and organic chemicals

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Journal of Energy Chemistry 2021年第3期30卷 386-394页

作者： Liangxuan Zhong Baodong Mao Meng Liu Mingyue Liu Yaqiu Sun yi-Tao Song Zhi-Ming Zhang Tong-bu Lu Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China Institute for New Energy Materials&Low Carbon Technologies School of Materials Science&EngineeringTianjin University of TechnologyTianjin 300384China School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Exploring highly efficient bifunctional photocatalysts for simultaneous H2 evolution and organic chemical production in pure water represents a green route for sustainable solar energy storage and ***,a facile strategy was explored for preparing a hierarchical porous heterostructure of Fe_(4)Ni_(5)S_(8)@ZnIn_(2)S_(4)(FNS@ZIS)by the in situ growth of ZIS nanosheets on Prussian blue analogue(PBA)-derived bimetallic FNS sulfides.A series of FNS@ZIS hierarchical structures were facilely prepared by adjusting the loading amount(n%)of FNS(n=19,26,and 32 for FNS@ZIS-1-3).These structures can efficiently drive the solar co-production of H_(2) and organic *** optimal co-production was achieved with FNS@ZIS-2,affording a H_(2) evolution rate of 10465μmol·g^(-1)·h^(-1),along with high selectivity for the oxidation of benzyl alcohol to benzaldehyde(>99.9%).The performance was 22 and 31 times higher than that of FNS and ZIS,respectively,and even superior to the state-of-the-art results achieved using various sacrificial *** mechanistic study indicated that the unique hierarchical core/shell architecture can facilitate interfacial charge separation,afford bimetallic synergy,abundant active sites and excellent *** work highlights a simple and efficient method for preparing porous multimetallic hierarchical structures for the solar co-production of organic chemicals and H_(2) fuel.

关键词： Prussian blue analogue Photocatalysis Hydrogen evolution Benzyl alcohol oxidation Coordination polymer

Radioanalytical chemistry for nuclear forensics in China:Progress and future perspective

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Chinese Chemical Letters 2022年第7期33卷 3384-3394页

作者： yi Liu Xuepeng Shao Wenting bu Zhen Qin Youyi Ni Fengcheng Wu Chuting Yang Xiaolin Wang Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621000China Institute of Materials China Academy of Engineering PhysicsMianyang 621000China China Academy of Engineering Physics Mianyang 621000China

A relatively new branch of science-nuclear forensics,aiming at providing the nature,origin,history and possible trafficking route of seized nuclear materials/devices,has been established and rapidly developed over decades to screen illicit nuclear *** highly interdisciplinary science is built upon a foundation of analytical chemistry,radiochemistry,nuclear physics,material sciences,geology,and other scientific disciplines,within which radiochemical methodologies and radioanalytical techniques play a key *** present review provides a brief overview about the crucial aspects of nuclear forensics,including basic content,procedure,concerned elements,common separation,analytical method,and so *** state of the art and recent progresses of nuclear forensics by research communities in China are reviewed,while selected examples and practical applications are *** challenges associated with this new area and on-going developments are highlighted and discussed.

关键词： Illicit nuclear material Nuclear forensics Radioanalytical techniques Mass spectrometry Isotopic composition

Physics performance of the STAR zero degree calorimeter at relativistic heavy ion collider

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Nuclear Science and Techniques 2016年第6期27卷 144-149页

作者： yi-Fei Xu Jin-Hui Chen Yu-Gang Ma Ai-Hong Tang Zhang-bu Xu Yu-Hui Zhu Shanghai Institute of Applied Physics Chinese Academy ofSciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China ShanghaiTech University Shanghai 200031China Brookhaven National Laboratory UptonNY 11973USA

The zero degree calorimeter(ZDC) at RHICSTAR was installed in the year *** running for more than 10 years,the performance of the STAR-ZDC cannot maintain a proper status because of the radiation *** ZDC on RHIC-BRAHMS had been moved to STAR in 2011 after some *** present here the result of the tests as well as the physical performance of those ZDC modules between the 2011 and 2015 RHIC *** excellent energy resolution of the ZDC in heavy ion collision provides a good candidate for future detector development,such as the CSR experiment at CAS-Lanzhou facility.

关键词：物理性能重离子对撞机零度量热计相对论企业社会责任 RHIC 能量分辨率

EXPLORATION　ON　THE　DEVELOPMENT　OF　COMPUTER　AIDED　EQUIPMENT　MAINTENANCE　MANAGEMENT　SYSTEMS

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中国有色金属学会会刊：英文版 1995年第4期5卷 158-167页

作者： bu, yingyong Zhang, Huailiang Central South Univ of Technology Changsha China

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关键词： computer-aided equipment maintenance management system

DOES INVESTOR SENTIMENT PREDICT STOCK RETURNS? THE EVIDENCE FROM CHINESE STOCK MARKET

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Journal of Systems Science & Complexity 2014年第1期27卷 130-143页

作者： bu Hui PI Li School of Economics and Management Beihang University

This paper examines the proxy variables of investor sentiment in Chinese stock market carefully, and tries to construct an investor sentiment index indirectly. We use cross correlation analysis to examine lead-lag relationship between the proxy variables and HS300 index. The results show that net added accounts （NAA）, SSE share turnover （TURN）, and closed-end fund discount （CEFD） are leading variables to stock market. The average first day return of IPOs （RIPO） and relative degree of active trading in equity market （RDAT） are contemporary variables, while number of IPOs （NIPO） is a lagging variable of stock market. Using the sentiment proxy variables with most possible leading order, and forward selection stepwise regression method, the empirical results on monthly stock returns reveal that three leading proxy variables can be used to form a sentiment index. And the out of sample tests prove that this sentiment index has good predictive power of Chinese stock market, and it is robust.

关键词： Chinese stock market investor sentiment return predictability.