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Theoretical Explanation of Uneven Transverse Temperature Distribution in Wide Thin Strip Rolling Process

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Journal of Iron and Steel Research International 2010年第4期17卷 18-23页

作者： tian li-li Paolo Patrizi ZHANG Jie Fabio Miani University of Science and Technology Beijing Beijing 100083 China University of Udine Udine 33100 Italy

A new theoretical thermomechanical explanation of the uneven transverse temperature distribution, along the width for thin and wide hot rolled strip was proposed. In particular, starting from the irregular pressure and friction distribution which led to an uneven heat generation, a 2D mathematical model of calculating the transverse termperature distribution was presented. A physical explanation for this problem was given and the model was used as an essential basis to build a corresponding FEM simulation model, in which heat loss and generation were considered. Deformation and friction heat were described in details. For a clearer and more logical analysis, the heat generation problem was split into two parts： one for the strip centre, and one for the sides, in correspondence with the temperature peak points at 100 mm from the strip edge. Finally, the result shows that how thenew theoretical model can lead to the exact interpretation of the measured uneven temperature distribution.

关键词： hot strip rolling strip temperature distribution strip thermomechanical behaviour deformation heat friction heat

Studies on the Relationship Between Electronic Structures and Superconducting Properties of TlBaCaCuO, BiSrCaCuO and XBaCuO(X=Y, Nd,Dy) Systems

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Chemical Research in Chinese Universities 1996年第1期12卷 60-69页

作者： li Ping XIAO Shen-xiu CHEN tian-lang and li li(Department of Chemistry, Sichuan University, Chengdu, 610064) SICHUAN UNIV DEPT CHEMCHENGDU 610064PEOPLES R CHINA

The electronic structures of TIBaCaCuO, BiSrCaCuO and XBaCuO (X = Y,Nd, DY) systems were calculated using DV-Xa method. According to the calculated results, the relationships between electronic structures and supercon... 详细信息

关键词： Superconductor DV-X_α method Populations State densities Energy gap

Coordinated organogel templated fabrication of silver/polypyrrole composite nanowires

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Chinese Chemical Letters 2011年第1期22卷 123-126页

作者： Bo tian li li Ming Tang Kai Chen Yu Xia Xin Jin Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.

关键词： Coordinated organogel Template polymerization Polypyrrole Composite nanowires

Synthesis and characterization of asymmetric substituted dicarbamates

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Chinese Chemical Letters 2011年第10期22卷 1167-1170页

作者： Chao Zhao Peng Fei Yang Shun Ping Wang Jun Ying li tian Duo li Shandong Provincial Key Laboratory of Fine Chemicals Shandong Polytechnic University Jinan 250353 China

Several new asymmetric substituted dicarbamates were synthesized with a convenient ***,tolylene-2,4-diisocyanate dimmer was obtained from monomer with tributylphosphine as ***,the dimmer reacted with alcohol（R^1OH） to prepare carbamate substituted ***,uretidione ring was opened and the released isocyanate reacted with another alcohol （R^2OH,R^1≠R^2）.

关键词： Asymmetric substituted dicarbamates Tolylene-2 4-diisocyanate Uretidione

Genotyping Characteristics of Human Fecal Escherichia coli and Their Association with Multidrug Resistance in Miyun District, Beijing

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Biomedical and Environmental Sciences 2023年第5期36卷 406-417页

作者： ZHANG Wei Wei ZHU Xiao lin DENG Le Le HAN Ya Jun li Zhuo Wei WANG Jin Long CHEN Yong liang WANG Ao lin tian Er li CHENG Bin XU lin Hua CHEN Yi Cong tian li li HE Guang Xue National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Miyun District Center for Disease Control and Prevention Beijing 101520China Berger Bioengineering Co. LtdShanghai 201401China Xicheng District Commission of Health of Beijing Municipality Beijing 100044China Miyun District Hospital Beijing 101520China Hebei North University Zhangjiakou 075000HeibeiChina

Objective To explore the genotyping characteristics of human fecal Escherichia coli(E. coli) and the relationships between antibiotic resistance genes(ARGs) and multidrug resistance(MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related *** Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs,multilocus sequence typing(MLST), and polymorphism trees were analyzed using whole-genome sequencing data(WGS).Results This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal(49/70) and healthy groups(15/24).Conclusion We developed a random forest(RF) prediction model of TEM.1 + baeR + mphA + mphB +QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers.

关键词： E.coli Multidrug resistance Whole-genome sequencing Antibiotic resistance genes Randomforest

Magnetism in Mn and Co doped ZnO bulk samples

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Chinese Science Bulletin 2007年第8期52卷 1019-1023页

作者： WANG YongQiang YUAN Songliu SONG YunXing liU li tian ZhaoMing li Pai ZHOU YuanMing li YunLong YIN ShiYan Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

Bulk samples with nominal composition Zn0.95Co0.05O and Zn0.92Co0.05Mn0.03O were fabricated by a solid-state reaction method at 600℃.X-ray diffraction experiment showed that the peaks of secondary phase Co3O4 with a cubic structure were visible in both samples,besides the main peaks of wurtzite structure as *** measurement indicated that doping Co alone can induce ferromag- netism in ZnO itself,while the introduction of Mn significantly enhances ***, both samples showed different magnetic behavior at temperatures below 50 *** was also noted that ferromagnetic coupling interaction was weakened due to the presence of antiferromagnetic Co3O4.

关键词：锰钴掺杂氧化锌块磁性铁磁现象

Peroxynitrite Scavenging Activities of Resveratrol and Piceid

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Chemical Research in Chinese Universities 2012年第6期28卷 953-956页

作者： ZHAO Guang-rong tian li-li MA Qiong WANG Chang-song QIAO Bin ZHANG Jun-gang JI Xiang-wu Key Laboratory of Systems Bioengineering Ministry of Education Department of Pharmaceutical Engineering School of Chemieal Engineering and Teehnology Tianjin University Tianjin 300072 P. R. China Department of Cardiology Weifang People's Hospital Weifang 261041 P. R. China

In vitro antioxidant activities of resveratrol and piceid against peroxynitrite（ONOO-） were examined by the inhibition of 3-nitrotyrosine *** was used as a positive *** and piceid exhibited high ONOO--scavenging activities in a concentration dependent *** antioxidant activities（the concentration of test compound required to yield a 50% inhibition of tyrosine nitration,IC 50） of resveratrol and piceid against ONOO-were（48.34±0.97） and（74.69±1.49） μmol/L,*** with that of trolox[（105.40±1.16） μmol/L],their scavenging activities were 2.2-and 1.5-fold higher for resveratrol and *** of nitroresveratrol as shown by UV-Vis spectroscopy and liquid chromatography-tandom mass spectrometry（LC-MS/MS） analysis indicates that resveratrol could directly scavenge ONOO-via nitration *** results demonstrate that foods and medicinal herbs with resveratrol and piceid as stronger ONOO-scavengers are valuable ingredients and have healthy application in preventing humans from peroxynitrite-mediated oxidative damage by scavenging peroxynitrite efficiently.

关键词： Resveratrol Piceid Peroxynitrite 3-Nitrotyrosine Antioxidant activity Nitration reaction Radical scavenging

Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs: a Preliminary Case-control Study

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Biomedical and Environmental Sciences 2014年第10期27卷 807-810页

作者： DOU Xiang Feng LYU Yan Ning JIANG Yi liN Chang Ying tian li li WANG Quan Yi YANG Yu Song li Chao SUN Yu Lan GUAN Zeng Zhi ZHANG Xiu Chun li Xin Yu Institute for Infectious and Endemic Diseases Control Beijing Center for Disease Prevention and Control State Key Laboratory for Infectious Diseases Prevention and Control National Institute of Communicable Disease Control & Prevention Chinese Center of Disease Control & Prevention Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Miyun Country Center for Disease Prevention and Control Huairou District Center for Disease Prevention and Control

A population-based case-control study was conducted to evaluate the relative fac^tors in the environments, agricultural works, outdoor activities, and the effectiveness of Lyme borreliosis （LB）- associated personal protective measure.c; in Beijing. Thirty-four cases and 272 controls were personally interviewed by well-trained interviewers. Venous blood samples were taken from eac：h subject. Sowing or harvesting in summer （OR=2.571, 95% CI： 1.109-5.962）, living in house with weeding in the yard （OR=2.247, 95% CI： 1.062-4.755）.

关键词： a Preliminary Case-control Study Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs

Simplified Analysis for Reflective Overpressure on Walls of Rectangle-Section Tunnel due to Its Inner-Explosion

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Transactions of tianjin University 2008年第5期14卷 363-370页

作者：田力李忠献周清 School of Civil Engineering Tianjin University

Based on the constructing thought of the displacement model of isoparametric finite element, an extended interpolating algorithm is deduced for calculating the overpressure history of an optional point on the walls of the rectangle-section tunnel under an optional point-explosion in its internal space. According to the working principle, the overpressure histories of all nodes on the walls of a tunnel with the equal width and height of 2 m, induced by a reference-charge explosion at each node in this tunnel's cross section, are computed using the LS-DYNA software, and then are gathered to establish a reference database, which makes it possible to set optionally the positions of the explosive and the overpressure-observed point. In addition, some variation factors of peak values and durations of overpressure on the walls, reflecting some changes on the charge weight and the sizes of width and height of the section, are included in this algorithm in order to simulate approximately the overpressure responses on the walls under the optional charge weight and cross-section size. Some example analyses indicate the rapidity and validity of this method, and therefore this will bring it a good prospect in engineering application.

关键词： rectangle-section tunnel reference database explosion overpressure charge weight