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Two New Antibacterial Flavanones from Sophora flavescens

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Chinese Chemical Letters 2006年第8期17卷 1048-1050页

作者： Mei ai CAO Xiao Bai SUN Pei Hua ZHAO Cheng shan YUAN State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S *** structures were e... 详细信息

关键词： Sophora flavescens Fabaceae flavanone antibacterial activity.

Group consensus of multi-agent systems subjected to cyber-attacks

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Chinese Physics B 2019年第6期28卷 91-98页

作者： Hai-Yun Gao ai-Hua Hu Wan-Qiang Shen Zheng-xian Jiang School of Science Jiangnan UniversityWuxi 214122China

In this paper, we investigate the group consensus for leaderless multi-agent systems. The group consensus protocol based on the position information from neighboring agents is designed. The network may be subjected to frequent cyberattacks, which is close to an actual case. The cyber-attacks are assumed to be recoverable. By utilizing algebraic graph theory, linear matrix inequality(LMI) and Lyapunov stability theory, the multi-agent systems can achieve group consensus under the proposed control protocol. The sufficient conditions of the group consensus for the multi-agent networks subjected to cyber-attacks are given. Furthermore, the results are extended to the consensus issue of multiple subgroups with cyber-attacks. Numerical simulations are performed to demonstrate the effectiveness of the theoretical results.

关键词： multi-agent systems group consensus cyber-attacks multiple subgroups

Comprehensive evaluation of rural courtyard utilization efficiency:A case study in shandong Province,Eastern China

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Journal of Mountain Science 2020年第9期17卷 2280-2295页

作者： LIU Ya-qiu WANG ai-ling HOU Jie CHEN Xin-yu XIA Jin-shan College of Resources and Environment Shandong Agricultural UniversityTaian 271018China College of Foreign Language Shandong Agricultural UniversityTaian 271018China

China is implementing the strategy of Rural *** idle and inefficient utilization courtyards is an important measure for rural *** evaluation of courtyard utilization efficiency is the basis of determining the idle and inefficient utilization courtyards in order to revitalizing *** study provided a reference for the optimal use of rural courtyard utilization and revitalization through the quantitative comprehensive evaluation of courtyard utilization efficiency and the classification of courtyard utilization *** shandong Province in Eastern China as study area,we selected eight surveyed villages by stratified sampling *** to the scale of the villages,full survey and sample survey were used,while middleaged men who familiar with the courtyards were selected as the *** a household questionnaire survey and face-to-face interviews from2017 to 2018,578 questionnaires of rural courtyardsin eight villages were *** based on the functions of rural courtyard and land resource conditions,16 comprehensive factors were formulated,involving land conditions,construction conditions and economic benefits,to build the comprehensive evaluation index system of rural courtyard utilization *** the index weight was determined by analytic hierarchy process,and the linear weighted regression model was used to evaluate the utilization efficiency of rural ***,the K-means clustering analysis was used to classify the utilization efficiency of *** results showed that among the eight villages,the average utilization efficiency of courtyards was moderate(one village was low,five were moderate,and two were high).The proportions of both idle and inefficiently utilized courtyards were *** were three vital factors leading to the idle and low efficiency of rural *** were declining rural industries,limited arable land per capita,and more farmer *** this

关键词： Rural courtyard Utilization efficiency Quantitative evaluation Obstacle factor

Inhibitory effect of oxymatrine on hepatocyte apoptosis via TLR4/PI3K/Akt/GSK-3β signaling pathway

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World Journal of Gastroenterology 2017年第21期23卷 3839-3849页

作者： xian Zhang Wei Jiang ai-Ling Zhou Min Zhao Dao-Rong Jiang Department of Infectious Diseases Affiliated Hospital of Nantong University Department of Science Technology and Industry Nantong University Department of Pathophysiology Medical School of Nantong University Department of Pathology Nantong Tumor Hospital

To evaluate the effect of oxymatrine (OMT) on hepatocyte apoptosis in rats with lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced acute liver failure (ALF).METHODSLPS/D-GalN was used to establish a model of ALF in rats. To evaluate the effect of OMT, we assessed apoptosis by transmission electron microscopy, and the pathological changes in the liver by light microscopy with hematoxylin and eosin staining. An automated biochemical analyzer was used to measure serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Enzyme-linked immunosorbent assay was used to determine the levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β. Western blotting was used to detect protein levels in liver tissues. Streptavidin peroxidase immunohistochemistry was used to observe expression of Toll-like receptor (TLR)4, active caspase-3, Bax and *** rats in the normal control and OMT-pretreated groups survived. The mortality rate in the model group was 30%. OMT preconditioning down-regulated apoptosis of hepatocytes and ameliorated pathological changes in liver tissue. The levels of AST, ALT, TNF-α and IL-1β in the model group increased significantly, and were significantly reduced by OMT pretreatment. OMT pretreatment down-regulated expression of TLR4 and active caspase-3 and the Bax/Bcl-2 ratio, and up-regulated expression of P-AktSer473 (Akt phosphorylated at serine 473) and P-GSK3βSer9 (glycogen synthase kinase 3β phosphorylated at serine 9) induced by LPS/*** inhibits hepatocyte apoptosis by suppressing the TLR4/PI3K/Akt/GSK-3β signaling pathway, which suggests that OMT is an effective candidate for ameliorating acute liver failure.

关键词： Oxymatrine Acute liver failure Toll-like receptor 4 Apoptosis

Analysis of Genetic Diversity in Natural Populations of Psathyrostachys huashanica Keng Using Microsatellite (SSR) Markers

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Agricultural Sciences in China 2010年第4期9卷 463-471页

作者： LIU Wen-xian LIU Wei-hua WU Jun GAO ai-nong LI Li-hui National Key Facility for Crop Gene Resources and Genetic Improvement （NFCRI） Institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Institute of Botany Chinese Academy of Sciences Beijing 100093 P.R.China Graduate School Chinese Academy of Sciences Beijing 100049 P.R.China College of Agronomy Northwest A＆F University Yangling 712100 P.R.China

Psathyrostachys huashanica Keng is endemic to China and only distributed in Huashan Mountain in Shaanxi Province, China. In this study, 15 P. huashanica populations consisting of 450 individuals sampled across their main distribution were investigated by using the simple sequence repeats （SSRs） markers. A total of 184 alleles were detected on 24 SSR loci, and the number of alleles on each locus ranged from 2 to15, with an average of 7.667. The total gene diversity （HT= 0.683） and the coefficient of population differentiation （GST = 0.125） showed that P. huashanica had a relatively high level of genetic variation, and the genetic variation was mainly distributed within the populations. The gene flow among the populations of P. huashanica （Nm = 1.750） was much less than that of the common anemophytes （Nm = 5.24）. Correlation analysis demonstrated that the number of alleles as well as genetic diversity of the five populations of Huangpu valley decreased along with the increase of altitudes, but the correlation was not significant. Implications of these results for future P. huashanica collection, evaluation and conservation were discussed.

关键词： Psathyrostachys huashanica Keng SSR genetic diversity conservation implication

Experimental Research of Electronic Devices Thermal Control Using Metallic Phase Change Materials

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 113-121页

作者： ai-Gang Pan Jun-Biao Wang xian-Jie Zhang Xiao-Bao Cao Shaanxi Engineering Research Center of Digital Manufacturing Technology Northwestern Polytechnical University

A Phase-change thermal control unit( PTCU) filled with metallic phase change material( PCM) Bismuth alloy for electric devices thermal protection was developed and investigated experimentally. The PTCU filled with PCM was designed and manufactured. Resistance heating components( RCHs) produced 1 W,3 W, 5 W,7W,and 10 W for simulating heat generation of electronic devices. At various heating power levels,the performance of PTCU were tested during heating period and one duty cycle period. The experimental results show that the PTCU delays RCH reaching the maximum operating temperature. Also,a numerical model was developed to enable interpretation of experimental results and to perform parametric studies. The results confirmed that the PTCU is suitable for electric devices thermal control.

关键词： bismuth alloy metallic phase change materials thermal control electronic device

Molecular Dynamics Simulations and Experimental Investigations of Atomic Diffusion Behavior at Bonding Interface in an Explosively Welded Al/Mg Alloy Composite Plate

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 983-991页

作者： Ting-Ting Zhang Wen-xian Wang Jun Zhou Xiao-Qing Cao Rui-shan Xie Yi Wei College of Materials Science and Engineering Taiyuan University of Technology shanxi Key Laboratory of Advanced Magnesium-Based Materials Ministry of Education Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Department of Mechanical Engineering Pennsylvania State University ErieThe Behrend College Department of Mechanical Engineering Key Laboratory for Advanced Materials Processing TechnologyTsinghua University

In this study, 6061 aluminum alloy and AZ31 B magnesium alloy composite plate was fabricated through explosive welding. Molecular dynamics（MD） simulations were conducted to investigate atomic diffusion behavior at bonding interface in the ai/Mg composite plate. Corresponding experiments were conducted to validate the simulation results. The results show that diffusion coefficient of Mg atom is larger than that of A1 atom and the difference between these two coefficients becomes smaller with increasing collision velocity. The diffusion coefficient was found to depend on collision velocity and angle. It increases linearly with collision velocity when the collision angle is maintained constant at 10° and decreases linearly with collision angle when the collision velocity is maintained constantly at 440 m/s. Based on our MD simulation results and Fick＇s second law, a mathematical formula to calculate the thickness of diffusion layer was proposed and its validity was verified by relevant experiments. Transmission electron microscopy and energy-dispersive system were also used to investigate the atomic diffusion behavior at the bonding interface in the explosively welded 6061/AZ31B composite plate. The results show that there were obvious Al and Mg atom diffusion at the bonding interface,and the diffusion of magnesium atoms from magnesium alloy plate to aluminum alloy plate occurs much faster than the diffusion of aluminum atoms to the magnesium alloy plate. These findings from the current study can help to optimize the explosive welding process.

关键词： Al/Mg composite plate Explosive welding Molecular dynamics simulation Atomic diffusionbehavior

Acetylene/argon mixture plasma to build ultrathin carbon bridge of CF_(x)/C/MnO_(2) for high-rate lithium primary battery

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Rare Metals 2024年第6期43卷 2574-2584页

作者： Da-Wei Zou Xing-Guang Fu Gao-Bang Chen Yi-Fan Liu Bao-shan Wu xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 31300lChina

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate ***,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)*** CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)*** with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

关键词： C_(2)H_(2)/Ar plasma Fluorinated carbon Lithium primary battery MnO_(2)

Microwave Effect On Partial Oxidation of Methane to Syngasover Ni/ZrO_2

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Chinese Chemical Letters 1998年第8期9卷 775-777页

作者： xian Jun BI Xiao Guang XIE ai Hong DUAN Pin Jie HONG Shu shan Dai(Department of Chemistry, Yunnan Normal University, Kunming 650092)(Department of Chemistry, Yunnan University, Kunming 650091) Yunnan Normal Univ Dept Chem Kunming 650092 Peoples R China Yunnan Univ Dept Chem Kunming 650091 Peoples R China

The partial oxidation of methane to syngas over Ni/ZrO2 catalyst irradiated by ndcrowave has been studied. Compared with a conventional heating mode, the temperature of the catalytic bed is much lower and there is a h... 详细信息

关键词： microwave partial Oxidation methane syngas Ni/ZrO_2