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Influence of Surface Structure of Platinum Electrodes on Electrooxidation of CO

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Chemical Research in Chinese Universities 2003年第4期19卷 474-480页

作者： XIA Xing-hua zhang Dai SONG Yan-yan State Key Laboratory of Coordination Chemistry Institute of Analytical ScienceNanjing UniveristyNanjing 210093P.R.China

The oxidation of CO on platinum electrodes in an acid solution was studied with the conventional electrochemical methods and the on-line electrochemical mass spectroscopy. It was found that this reaction is strongly determined by the surface morphology of platinum. The pretreatment of platinum electrodes can change the surface properties dramatically, in consequence it can improve the electrocatalytic activity towards the electrooxidation of CO. The existence of surface active sites on the roughened platinum electrodes can be used to explain its high electrocatalysis towards the oxidation of CO.

关键词： Electrocatalysis Platinum Surface property Mechanism

Development of Oligo-GISH kits for efficient detection of chromosomal variants in peanut

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The Crop Journal 2023年第1期11卷 238-246页

作者： Pei Du Liuyang Fu Qian Wang Tao Lang hua Liu Suoyi Han Chenyu Li Bingyan huang Li Qin Xiaodong Dai Wenzhao Dong Xinyou zhang Henan Academy of Crop Molecular Breeding/State Industrial Innovation Center of Biological Breeding/The Shennong Laboratory/Key Laboratory of Oil Crops in huang-huai-Hai Plains Ministry of Agriculture/Henan Provincial Key Laboratory for Oil Crops ImprovementHenan Academy of Agricultural SciencesGraduate T&R Base of Zhengzhou UniversityZhengzhou 450002HenanChina Institute of Biotechnology and Nuclear Technology Sichuan Academy of Agricultural SciencesChengdu 610061SichuanChina

Oligo probe staining is a low-cost and efficient chromosome identification *** this study,oligo genomic in situ hybridization(Oligo-GISH)technology was established in *** A and B subgenome-specific interspersed repeat(IR)oligo probe sets were developed based on clustering and electronic localization of tandem repeat sequences in the reference genome of *** OligoGISH kit was then used to perform staining of 15 Arachis *** A-subgenome probe set stained the chromosomes of A-and E-genome Arachis species,the B-subgenome probe set stained those of B-,F-,K-,and E-genome species,and neither set stained those of H-genome *** results indicate the relationships among the genomes of these Arachis *** Oligo-GISH kit was also used for batch staining of the chromosomes of 389 seedlings from the irradiated M1generation,allowing 67 translocation and deletion lines to be *** Oligo-FISH karyotyping,FISH using single-copy probe libraries,and trait investigation identified seven homozygous chromosomal variants from the M3generation and suggested that there may be genes on chromosome 4B controlling seed number per *** findings demonstrate that the IR probe sets and method developed in this study can facilitate research on distant hybridization and genetic improvement in peanut.

关键词： Peanut Oligo-GISH Genomic relationship Variants Chromosome identification

Design of a CMOS Distributed Power Amplifier with Gradual Changed Gain Cells

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Chinese Journal of Electronics 2018年第6期27卷 1158-1162页

作者： zhang Ying LI Zeyou YANG hua GENG Xiao zhang Yi College of Electronic and Optical Engineering College of Microelectronics Nanjing University of Posts and Telecommunications National and Local Joint Engineering Laboratory of RF Integration and Micro-Assembly Technology Nanjing University of Posts and Telecommunications

A non-uniform Distributed power amplifier(DPA) is designed and implemented in a 0.18μm CMOS technology. The gradual changed gain cells work with the tapered on-chip inductors to construct non-uniform artificial transmission lines, which improves the output power and efficiency in a wide frequency band while maintaining good input and output impedance matching. The proposed DPA achieves 9 dB average associated gain from 1 to 17.2 GHz, and the input return loss is less than--9 dB while the output return loss is less than-8.5 dB in the desired frequency band. The output power at 1 dB Output compression point(OP1 dB) is more than 7.8 dBm in the frequency band of 2-16 GHz, and the peak power-added efficiency is 6.2% with the OP1 dB12.6 dBm at 4 GHz.

关键词： Distributed amplifier Impedance matching Power added efficiency Artificial transmission line

青藏高原水循环中高原低涡及多季风交汇的研究进展

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沙漠与绿洲气象 2024年第2期18卷 1-11页

作者：华维邓浩夏昌基张永莉朱丽华赖欣范广洲成都信息工程大学大气科学学院四川成都610225 高原大气与环境四川省重点实验室四川成都610225 四川省气象灾害预测预警工程实验室四川成都610225 中国电力工程顾问集团西南电力设计院有限公司四川成都610056 镇远县气象局贵州镇远557700

青藏高原以其特殊而强大的动力和热力效应,导致东亚季风、印度季风和高原季风在高原及周边地区交汇。受多季风交汇影响,青藏高原低涡的水循环过程极为复杂,而高原低涡水循环异常往往可造成高原及周边乃至我国中东部地区频发灾害性天气,... 详细信息

青藏高原以其特殊而强大的动力和热力效应,导致东亚季风、印度季风和高原季风在高原及周边地区交汇。受多季风交汇影响,青藏高原低涡的水循环过程极为复杂,而高原低涡水循环异常往往可造成高原及周边乃至我国中东部地区频发灾害性天气,因此一直是国内外学者关注的热点和难点问题。本文回顾了国内外关于高原低涡活动特征、结构特征、生成发展机制等方面研究进展,从高原低涡水汽输送、低涡降水和云—降水物理过程等角度概括了高原低涡参与水循环过程研究成果,在总结东亚季风、印度季风和高原季风相互作用研究的基础上分析了多季风交汇对高原水循环的影响。对多季风作用下高原低涡影响水循环方面存在的问题进行了讨论,并展望了未来研究方向。

关键词：多季风交汇高原低涡水循环

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Intestinal immune barrier integrity in rats with nonalcoholic hepatic steatosis and steatohepatitis

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Chinese Medical Journal 2012年第2期125卷 306-311页

作者： Su Lin Wang Jian-hua Cong Xu Wang Li-hong Liu Feng Xie Xing-wang zhang Heng-hui Wang Jiang-hua Fei Ran Liu Yu-lan Peking Univ Peoples Hosp Dept Gastroenterol Beijing 100044 Peoples R China Peking Univ Peoples Hosp Inst Hepatol Beijing 100044 Peoples R China Univ Sydney Westmead Millenium Inst Storr Liver Unit Sydney NSW 2145 Australia Westmead Hosp Sydney NSW 2145 Australia

Background Nonalcoholic fatty liver disease （NAFLD） has emerged as the major cause of chronic liver *** barrier plays an important role in the pathogenis of *** aim of this article was to assess intestinal immune barrier function during the development of *** Totally 60 male Sprague-Dawley （SD） rats were divided into 2 groups：normal diet （ND） group and high-fat diet （HFD） *** rat model was established in the HFD rat *** blood endotoxin level was assessed by limulus *** percentage of CD4＋ cells and CD8＋ cells in peripheral blood mononuclear cells （PBMC） and lymphocytes in Peyer＇s patches （PP） were analysed by flow *** secretory immunoglobulin A （SIgA） level was evaluated by enzyme-linked immunosorbent *** Student＇s t test was used for the statistic *** HFD rats presented with simple steatosis at the 4th and 8th week and progressed to nonalcoholic steatohepatitis at the 12th *** lipopolysaccharides （LPS） level in HFD rats was observed at the 8th week （（1.54±0.30） times of ND group,P 〈0.01）.CD4/CD8 ratios in PBMC and PP of HFD rats were increased at the 4th week （（1.50±0.47） and （1.63±0.34） times of ND group,P 〈0.05） and decreased at the 8th week （（0.50±0.16） and （0.61±0.26）times of ND group,P 〈0.05）.At the 12th week,CD4/CD8 ratio （（1.47±0.46） times,P 〈0.05） in PP increased to levels observed in the 4th *** SIgA expression of HFD rats was remarkably up-regulated at 12th week （（2.70±1.65）times,P 〈0.05）.Conclusion Liver-gut axis in rats with NAFLD may mediate and improve intestinal immune function by increased CD4/CD8 ratio in PP and increased production of SIgA.

关键词： non-alcoholic fatty liver disease intestinal immune barrier endotoxins CD4/CD8 immunoglobulin A, secretory

Credit Determination of Fibre Channel in Avionics Environment

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Chinese Journal of Aeronautics 2007年第3期20卷 247-252页

作者： LIN Qiang XIONG hua-gang zhang Qi-shan School of Electronic and Information Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

Fibre channel （FC） is the main candidate architecture for ＂unified network＂. Flow control deals with the problem in which a device receives frames faster than it can process them. Credit is an important service parameter for fibre channel flow control. Configuring the credit reasonably can avoid buffer overflow in nodes. This paper derives the mathematic relationships among credit, bandwidth and message sets under real-time condition according as three main topologies of fibre channel, and proposes the credit determination and the optimal credit for typical message sets. This study is based on the features of hard real-time communications in avionics environment.

关键词： fibre channel topology login credit hard real-time condition

Intergranular corrosion behavior of high nitrogen austenitic stainless steel

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 654-660页

作者： hua-bing Li Zhou-hua Jiang Zu-rui zhang Yang Cao Yan Yang School of Materials and Metallurgy Northeastern University Shenyang 110004 China

The intergranular corrosion （IGC） behavior of high nitrogen austenitic stainless steel （HNSS） sensitization treated at 650-950℃ was investigated by the double loop electrochemical potentiodynamic reactivation （DL-EPR） method. The effects of the electrolytes, scan rate, sensitizing temperature on the susceptibility to IGC of HNSS were examined. The results show that the addi-tion of NaCl is an effective way to improve the formation of the cracking of a passive film in chromium-depleted zones during the reactivation scan. Decreasing the scan rate exhibits an obvious effect on the breakdown of the passive film. A solution with 2 mol/L H2SO4＋1 mol/L NaCl＋0.01 mol/L KSCN is suitable to check the susceptibility to IGC of HNSS at a sensitizing temperature of 650-950℃ at a suitable scan rate of 1.667 mV/s. Chromium depletion of HNSS is attributed to the precipitation of Cr2N which results in the susceptibility to IGC. The synergistic effect of Mo and N is suggested to play an important role in stabilizing the passive film to prevent the attack of IGC.

关键词： intergranular corrosion high nitrogen austenitic stainless steel sensitization passive film chromium depletion

Effect of Intercritical Annealing Time on the Microstructures and Tensile Properties of a High Strength TRIP Steel

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Acta Metallurgica Sinica(English Letters) 2014年第3期27卷 457-463页

作者： Chao Wang hua Ding Jun zhang hongyan Wu School of Materials and Metallurgy Northeastern University State Key Laboratory of Rolling and Automation Northeastern University

A new Mn-Si-Al-Mo-Nb transformation-induced plasticity steel was annealed by intercritical annealing for different durations to investigate the partitioning of C element and the volume fraction change of the microstructural constituents. Direct experimental evidence confirms the partitioning of C elements in different phases during heat treatment by Electron probe microanalysis and X ray diffraction. The distribution of the precipitates was investigated as well. It was revealed that the microstructures and mechanical properties of the investigated steels were affected by the intercritical annealing time. According to the present experiment, the volume fraction of retained austenite and the product of tensile strength and total elongation of investigated steel decrease with increasing intercritical annealing time. It was observed that high tensile strength of 1,103 MPa, total elongation of 21.3%, and strength-ductility product of 23,493.9 MPa % could be successfully produced in this experimental steel at intercritical annealing temperature of 830 ℃, holding for 1 min, and isothermal bainite treatment of 440 ℃ for 5 min holding time.

关键词： TRIP steel Intercritical annealing Carbon partitioning Retained austenite Stability

Multivariable sliding mode backstepping controller design for quadrotor UAV based on disturbance observer

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Science China(Information Sciences) 2018年第11期61卷 155-170页

作者： Zheng zhang Fang WANG Ying GUO Changchun hua School of Science Yanshan University School of Electric Engineering Yanshan University

This paper deals with the tracking control problem of quadrotor unmanned aerial vehicles(QUAVs) with external disturbances. First, because the QUAV model contains two non-integrity constraints,the dynamic model of the QUAV is decomposed into two subsystems which are independently controlled, so as to reduce controller design complexity. Secondly, the nonlinear disturbance observer(DOB) technique is integrated into a backstepping control method to design the controller for the first subsystem, in which a DOB is applied to estimate the lumped uncertainty. Based on the double power reaching law and the DOB,a multivariable sliding mode control(MSMC) scheme is developed for the second subsystem. Thirdly, based on Lyapunov theory, the closed-loop system is proved to be asymptotically stable. Finally, our comparative simulation results demonstrate that the presented control scheme behaves better in terms of tracking performance than the adaptive backstepping control(ABC) approach.

关键词： quadrotor unmanned aerial vehicle QUAV nonlinear DOB backstepping control sliding mode control power reaching law