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Chemical Research in Chinese Universities 2001年第4期17卷 439-444页

作者： WU Shi-hua WEI Wei zhu Chang-ying HUANG Wei-ping ZHANG Shou-min ZHENG Xiu-cheng ZHANG Shu-hong ZHAO Wei-jun Department of Chemistry Naikai UniversityTianjin 300071P.R.China

Co-Pd bimetallic catalysts immobilized with four kinds of resins with different specific areas were prepared by means of the solvated metal atom impregnation (SMAI) method. The results of the XRD and the magnetic measurement showed that as the specific area of the resin increased, the particle sizes of Co and Pd on the catalysts with the same metal content decreased, so the catalytic activity of the catalysts for the hydrogenation of diacetone alcohol as well as the reduction of oxygen on the fuel cell electrode increased. Below 140 , the conversion of diacetone alcohol increased as the reaction temperature increased, and above 140 , the conversion decreased because of the rupture of the resin.

关键词： Cobalt-palladium catalyst Diacetone alcohol hydrogenation Fuel cell electrode

城市人工湖泊浮游植物群落结构及环境因子分析

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水生态学杂志 2024年第2期45卷 92-101页

作者：魏秘王瑞王竹周连凤张俊芳王辉吕克强韩增辉彭增辉胡菊香水利部中国科学院水工程生态研究所水利部水工程生态效应与生态修复重点实验室湖北武汉430079 湖南湘新水务环保投资建设有限公司湖南长沙410006 湖南水天地环保科技有限公司湖南长沙410006

探究梅溪湖浮游植物群落结构与环境因子的关系,为城市人工湖泊水生态系统修复与治理提供基础资料与理论依据。2020-2021年布设7个采样点按季度进行采样,分析浮游植物群落组成、时空分布及其与环境因子的关系。结果显示4个季度梅溪湖水... 详细信息

探究梅溪湖浮游植物群落结构与环境因子的关系,为城市人工湖泊水生态系统修复与治理提供基础资料与理论依据。2020-2021年布设7个采样点按季度进行采样,分析浮游植物群落组成、时空分布及其与环境因子的关系。结果显示4个季度梅溪湖水体溶解氧、pH、氨氮、高锰酸盐指数等指标均处于Ⅱ类水质标准范围内,总磷处于Ⅱ~Ⅲ类水质标准,总氮在春秋冬季含量较高。共在梅溪湖检出浮游植物7门96种,其中以绿藻、硅藻和蓝藻种类数居多,共占总种类数的86.46%,主要优势种为细小隐球藻(Aphanocapsa elacjista)、小环藻(Cyclotella sp.)、链状曲壳藻(Achnanthes catenata)和尖尾蓝隐藻(Chroomonas acuta),优势种具有明显季节交替性。浮游植物年均密度为(23.97±9.95)×10^(6)个/L,各季度东部水域密度均高于西部水域;多样性指数评价结果表明梅溪湖水体处于中度污染和中-富营养状态,与水质评价结果基本一致。浮游植物与环境因子基于转化的冗余分析结果显示,水温、氧化还原电位、总氮和亚硝酸盐氮是影响梅溪湖浮游植物群落的主要驱动因子。控制总氮等营养盐的输入是改善梅溪湖水质和营养状态的有效手段。

关键词：人工湖泊浮游植物环境因子群落结构梅溪湖

A novel method for the synthesis of sulfur substituted-cyclopyrophosphate of cADPR analogs

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Chinese Chemical Letters 2014年第12期25卷 1583-1585页

作者： Ren-Min Wu Na Qi Yu-Wen Jia zhu Guan Liang-Ren Zhang Li-He Zhang Zhen-jun Yang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University

A facile and efficient protocol for the synthesis of sulfur substituted-cyclopyrophosphate of cIDPRE（P_S^1-cIDPRE） was *** key step was the cyclization process which was completed by the sulfur substituted cyclizati... 详细信息

关键词： cADPR cIDPRE Phosphoramidite strategy Cyclopyrophosphate

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汽车电线束连接强度试验能力验证的研究

环境技术 2024年第1期42卷 120-123页

作者：何闯李馨贵陈宇军王珊珊朱珈威凯检测技术有限公司广州510663

汽车电线束是一种用于连接和传输电力、信号和数据的系统,在现代汽车中扮演着关键的角色。本文围绕汽车电线束连接强度试验能力验证计划,介绍了计划实施流程并给出技术建议,希望对实验室有所帮助。

关键词：连接强度汽车电线束能力验证

Design of an Invisible Radome by Frequency Selective Surfaces Loaded withLumped Resistors

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Chinese Physics Letters 2013年第6期30卷 94-97页

作者： LIU Li-Guo LI You-quan MENG Qing-Zhi WU Wei-Wei MO Jin-jun FU Yun-Qi YUAN Nai-Chang College of Electronic Science and Engineering National University of Defense TechnologyChangsha 410073 Air Force Early Warning Academy Wuhan 430019 Special Operations University Guangzhou 510500

A novel radome is presented,which is transparent at operating frequency and is invisible out of *** order to prevent reflection of the incoming power,frequency selective surfaces loaded with the lumped resistors are *** obtain the pass-band properties in lower frequencies,the convoluted slots are *** comparison with the results obtained both by full wave analysis and by the measurements,the performance of the radome is *** performs with high transmission characteristics in band,and broadband absorbing properties out of band *** oblique incidences are also investigated for both transmission coefficients and reflection ones.

关键词： transparent utilized absorbing

基于特性的牵引车-半挂车刚柔组合车架动力学模型研究

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汽车工程 2024年第3期46卷 448-455页

作者：管欣李力孙磊段春光崔晨雪黄伟朱宝黎詹军靳宇轩吉林大学汽车底盘集成与仿生全国重点实验室长春130022 中国重型汽车集团有限公司济南250000

商用车较大的车架柔性会影响到整车的操纵稳定性和乘坐舒适性,尤其是在共振时车架柔性会放大对车辆运动品质的影响。为实时模拟牵引车-半挂车的车架运动,采用基于总成特性的建模技术路线,根据运动响应频域将车架运动解耦为低频刚体运动... 详细信息

商用车较大的车架柔性会影响到整车的操纵稳定性和乘坐舒适性,尤其是在共振时车架柔性会放大对车辆运动品质的影响。为实时模拟牵引车-半挂车的车架运动,采用基于总成特性的建模技术路线,根据运动响应频域将车架运动解耦为低频刚体运动和高频柔体运动,并将车架模型模块化划分为基于多体动力学的刚体车架模块、基于模态综合法的柔体车架模块,然后将两模块求解结果叠加形成刚柔组合车架模型。最后,将车架模型嵌入牵引车89DOF-半挂车73DOF整车模型中,针对某款商用车进行仿真,通过对比实车场地试验结果,验证了模型的有效性。

关键词：车架刚柔组合牵引车-半挂车特性动力学模型

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中国出版业标准化概况

出版发行研究 2006年第12期 23-26页

作者：朱诠中国出版科学研究所

面对经济全球化进程进一步加快,科技进步日新月异.综合国力争日趋激烈的大势,标准作为一种技术基础,已经成为重要的竞争手段.当今世界谁掌握了标准,谁就掌握了竞争的主动权.

关键词：中国出版业标准化经济全球化进程全面建设小康社会贸易技术壁垒综合国力竞争竞争手段科技进步

Characterization of Salmonella Enterica Serotype Typhimurium from Outpatients of 28 Hospitals in Henan Province in 2006

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Biomedical and Environmental Sciences 2009年第2期22卷 136-140页

作者： MIN zhu ZHI-QIANG XIE LI-SHI ZHANG SHENG-LI XIA WEI-ZHONG YANG LU RAN AND ZI-jun WANG Huaxi School of Public Health Sichuan University Chengdu 610041 Sichuan China Henan Center for Disease Control and Prevention Zhengzhou 450016 Henan China Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective To characterize the diarrheal patients with Salmonella typhimurium （S. typhimurium） infections and to set up the first baseline for S. typhimuri_um pulsed-field gel electrophoresis （PFGE） patterns in Henan province, thus laying a foundation for comprehensive surveillance of Salmonella in human as well as foods. Methods S. typhimurium isolates recovered from outpatients with diarrhea in Henan province from May to October of 2006 were characterized. Antimicrobial susceptibility tests of 8 antimicrobial agents and PFGE were carried out to analyze the S. typhimurium isolates. Results Twenty-four （0.9%） S. typhimurium isolates were identified from 2661 stool specimens of diarrheal cases. Eighty-eight percent of isolates showed resistance to at least one antimicrobial agent. The resistance to chloramphenicol （79%） was most common. Fifty-eight percent of isolates were resistant to ciprofloxacin. All the 14 ciprofloxacin-resistant isolates were resistant to more than five antimicrobial agents. Thirty-three percent of S. typhimurium isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline （R-type ACSSuT）. Eight antimicrobia-resistant phenotypes were found among the 24 isolates in 16 PFGE patterns. Conclusion The rate of multidrug-resistant S. typhimurium is relatively high in S. typhimurium PFGE patterns of Henan province. Multidrug-resistant S. typhimurium should be considered a public health threat.

关键词： Salmonella typhimurium Outpatients Ciprofloxacin Multidrug-Resistant Pulsed-field gel electrophoresis

Influence of distance between paralleled metal fibers on giant magnetoimpedance

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Journal of Iron and Steel Research International 2018年第3期25卷 255-260页

作者： Shu-ling Zhang Wei-ye Chen Gui-hong Geng Zi-qiang Han Yong-chuan Yu Bo Zhang Wen-jie Ding Xue-jun zhu School of Mechanical Engineering Ningxia UniversityYinchuan 750021 Ningxia China School of Material of Science and Engineering North MinzuUniversity Yinchuan 750021 Ningxia China

Giant magnetoimpedance （GMI） and the GMI effect of a Co-based fiber beam were investigated in the frequency range of 0.1-10 MHz, and the influence of distance between adjacent fibers on the distribution of the surface circumferential magnetic field and GMI effect was analyzed. Compared with a single fiber, the distribution of the surface magnetic field of paralleled fibers is non-uniform, induced by magnetic interaction between metal fibers. The originally uniformly dis- tributed circumferential magnetic field changes into two obvious coexisting parts： one stronger and one weaker. The results prove that the strengthened circumferential magnetic field determines the GMI effect and sensitivity. It is found that the maximum surface of the circumferential magnetic field is reinforced by 88% when the four fibers are as closely parallel as possible; the GMI effect is greatest under higher field sensitivity. At 5 MHz, the sensitivity of the four-fiber beam reaches 3090 V/T, an increase of 277% compared with a single fiber. However, the magnetic interaction fades with the increase in distance between fibers and as the distribution of the surface magnetic field becomes even. The maximum magnetic field also becomes gradually equal to the level of a single fiber. When the distance is 1 mm, the maximum surface magnetic field is increased by 3.2%, and the improvement in the GMI effect is correspondingly slight. Therefore, a strong magnetic interaction among fibers can improve the intensity of the surface circumferential magnetic field and give rise to a fine GMI effect and high field sensitivity in Co-based metal fibers.

关键词： Giant magnetoimpedance-Metallic fiber Sensitivity Magnetization-Magnetic interaction Sensor

Reversal of multidrug resistance in renal cell carcinoma by short hairpin RNA targeting MDR1 gene

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Chinese Medical Journal 2012年第15期125卷 2741-2745页

作者： HAO Yi-xin HE Zheng-wen zhu Jian-hua SHEN Qian SUN jun-zhong DU Nan XIAO Wen-hua Department of Oncology First Affiliated Hospital of the People'sLiberation Army General Hospital Beijing 100048 China Department of Laboratory Diagnosis Claanghai Hospital SecondMilitary Medical University Shanghai 200433 China

Background Over-expression of P-glycoprotein （P-gp）, encoded by the MDR1 gene, confers multidrug resistance （MDR） in renal cell carcinoma （RCC） and is a major reason for unsuccessful chemotherapy. This study aimed to determine the effct of RNA interference （RNAi） on the reversal of MDR in human RCC. Methods We designed and selected one short hairpin RNA （shRNA） targeting MDR1 gene, which is stably expressed from integrated plasmid and transfected by lentivirus fluid in human RCC A498 cell. Results The MDRl-targeted RNAi resulted in decreased MDR1 gene mRNA level （P 〈0.001）, almost abolished P-gp expression and reversed MDR to different chemotherapy drugs in the RCC A498 cell line. Conclusion MDR could be reversed by RNAi in human RCC A498 cell line, which may be used for clinical application

关键词： multidrug resistance, P-glycoprotein short hairpin RNA renal cell carcinoma