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Flexible paired-orthogonal codes for multi-user MIMO-OFDM

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 36-41页

作者： WANG Ya-chen FAN Yan-hong ma xiao-feng LI Ye Shandong Computer Science Center Jinan 250014 China Shandong Provincial Key Laboratory of Computer Network Jinan 250014 China

The work proposes two novel spreading codes, called extensive double-orthogonal code （EDOC） and flexible paired-orthogonal code （FPOC）, for multi-user downlink multiple-input multiple-output （M1MO） orthogonal frequency division multiplexing （OFDM） systems. The goal of code designs is to obtain an improved bit error rate （BER） performance without loss of bandwidth efficiency. The code designs achieve space diversity by employing multiple antennas at both transmit ends and receive ends. Codes are reasonably spread into time, frequency and space domain. The proposed codes are attractively characterized with length flexibility, which breaks the ＂power of two＂ constraint. The simulation results indicate that the proposed codes improve overall BER performance, by exploiting space diversity gains. The flexibility in code length also results in high spectral efficiency.

关键词： flexible paired-orthogonality MIMO OFDM multi-user space diversity

Synthesis and characterization of novel polypropylene paper releasing anion

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Chinese Chemical Letters 2009年第4期20卷 483-486页

作者： Li Qiu Wang Qing Shan Li Hui Peng ma xiao feng Guo Rui Hong Wang Gang Yao College of Environmental and Chemical Engineering State Key Laboratory of Metastable Materials Science and Technology Yanshan University State Key Laboratory of Metastable Materials Science and Technology Qinhuangdao 066004 China

Polypropylene synthetic paper releasing anion was prepared from polypropylene resin, anion additives, titanium dioxide, etc., by calendar forming method. The synthetic paper was tested by anion detector, SEM, AFM, etc. Tensile strength, elongation at break, fight angle tear strength of the polypropylene synthetic paper reached the GB 13022 or QB/T1130 Standard. The synthetic paper was water and oil resistance, and released anions 10,530 cm^-3. It was environment-friendly, and a kind of good material for human＇s health.

关键词： Synthetic paper Polypropylene Functional polymer Health material Anions releasing

Identification of salinity-related genes in ENO2 mutant (eno2~–) of Arabidopsis thaliana

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Journal of Integrative Agriculture 2018年第1期17卷 94-110页

作者： ZHANG Yong-hua CHEN Chao SHI Zi-han CHENG Hui-mei BING Jie ma xiao-feng ZHENGChao-xing LI Hong-jie ZHANG Gen-fa Beijing Key Laboratory of Gene Resource and Molecular Development/College of Life Sciences Beijing Normal University Beijing 100875 P.R.China Beijing Normal University Zhuhai 519087 P.R.China National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

Abiotic stress poses a great threat to plant growth and can lead to huge losses in yield. Gene enolase2 （EN02） is important in resistance to abiotic stress in various organisms. ENO2 T-DNA insertion mutant （enoZ） plants of Arabidopsis thaliana showed complete susceptibility to sodium chloride treatment when were analyzed either as whole plants or by measuring root growth during NaCl treatment. Quantitative real-time RT-PCR （RT-qPCR） was performed to investigate the expression profile of EN02 in response to NaCl stress in Arabidopsis. The transcript level of EN02 was rapidly elevated in 300 mmol L-1 NaCl treatment. ENO2 also responded to 300 mmol L 1 NaCl treatment at the protein level. To illuminate the mechanism underlying EN02 resistance to salt at the transcriptional level, we studied the wild-type and enoZ Arabidopsis lines that were treated with 300 mmol L 1 NaCl for 18 h using 454 GS FLX, which resulted in an expressed sequence tag （EST） dataset. A total of 961 up-regulated and 746 down-regulated differentially expressed genes （DEGs） were identified in the pairwise comparison w-r-18 h：eno2^-18 h. The DEGs were identified and functionally annotated using the databases of Gene Ontology （GO） and the Kyoto encyclopedia of genes and genomes （KEGG）. The identified unigenes were subjected to GO analysis to determine biological, molecular, and cellular functions. The biological process was enriched in a total of 20 GO terms, the cellular component was enriched in 13 GO terms, and the molecular function was enriched in 11 GO terms. Using KEGG mapping, DEGs with pathway annotations contributed to 115 pathways. The top 3 pathways based on a statistical analysis were biosynthesis of the secondary metabolites （KO01110）, plant-pathogen interactions （KO04626）, and plant hormone signal transduction （KO04075）. Based on these results, EN02 contributes to increased resistance to abiotic stress. In particular, EN02 is involved in some of the metabolic stress response pathways in

关键词： EN02 NaCI tolerance abiotic stress 454 GS FLX sequencing GO KEGG

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阻燃抗静电聚甲醛复合材料的制备及性能研究

塑料工业 2017年第10期45卷 113-116页

作者：马小丰开滦煤化工研发中心河北唐山063611 河北省煤基材料与化学品工程技术研究中心河北唐山063018

采用抗静电剂与氮-磷阻燃剂进行复配,制备了阻燃抗静电改性聚甲醛,并研究了阻燃抗静电复配助剂对聚甲醛的表面电阻率、阻燃性能、力学性能和热稳定性的影响。结果表明,随着导电炭黑和碳纳米管含量的逐渐提高,聚甲醛复合材料的表面电阻... 详细信息

采用抗静电剂与氮-磷阻燃剂进行复配,制备了阻燃抗静电改性聚甲醛,并研究了阻燃抗静电复配助剂对聚甲醛的表面电阻率、阻燃性能、力学性能和热稳定性的影响。结果表明,随着导电炭黑和碳纳米管含量的逐渐提高,聚甲醛复合材料的表面电阻率逐渐降低,其中碳纳米管效果更佳;当复配体系中聚磷酸铵/三聚氰胺尿酸盐/热塑性酚醛树脂/碳纳米管比例为20/7/3/10时,聚甲醛复合材料的阻燃级别为FV-1级,表面电阻率为104Ω,拉伸强度和缺口冲击强度分别为46.2 MPa和3.8 kJ/m^2。

关键词：聚甲醛表面电阻率阻燃性能力学性能

Research of Anti Electromagnetic Interference Technology for PMSM Driving System

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Research of Anti Electromagnetic Interference Technology for...

Increased Transendothelial Cells Permeability Induced by Oxidized Lipoprotein(a) Relates to Reactive Oxygen Species Generation and Desmogleins Expression

2010 3rd International Conference on Computer and Electrical Engineering(ICCEE 2010)

作者： Bai Gong-ding ma xiao-feng Science and Technology on Vehicle Transmission Laboratory CNGC China North Vehicle Research Institute

The permanent magnet synchronous motor (PMSM) is a key part of hybrid power vehicle’s driving system, and the reliability of its control is important for the normal use. With more and more electronic equipments settled in the vehicle, the type and quantity of electromagnetic interference are increasing, and will finally affect the motor driving system’s reliability. This paper analyzed the sources of interferences in the driving system, and solved them with circuit preplan and design. With the experiment, these solutions were effective and improved the driving system’s reliability.

关键词： Permanent magnet synchronous motor (PMSM) electromagnetic interference driving system

来源： cnki会议评论

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Chinese Journal of Biomedical Engineering(English Edition) 2016年第3期25卷 127-133页

作者： WANG Zuo YANG Jian ZHANG xiao-lei ma xiao-feng WANG Ren ZENG Jun-fa WEI Deng-heng ZHANG Kai LI Shuang LIN xiao-long ZHAO Yue JIANG Zhi-sheng Institute of Cardiovascular Research Key Laboratory for Arteriosclerology of Hunan Province University of South China

Objective: This paper aims at measurement enhanced effect of oxidized lipoprotien(a) [ox Lp(a)] on permeability of monolayer endothelial cells and relationship with reactive oxygen species(ROS) generation and desmogleins(DSGs) *** and Results: Transendothelial permeability was assayed by transwell and reactive oxygen species(ROS) was determined by DCFH-DA staining. RT-PCR was carried out to determine DSGl and DSC2 expression in m RNA, *** permeability was enhanced by ox LP(a) dose and time dependently. The most marked effect appeared at a concentration of 100 mg/L, Transendothelial permeability reached the maximum value after 2 h of FITC-dextran addition, and then gradually decreased after 4 h. ox Lp(a) induces the generation of cellular reactive oxygen species(ROS), and this effect could be inhibited by superoxide dismutase(SOD).Incubation of HUVECs with ox Lp(a) resulted in a dose and time-dependent down-regulation of DSGl and DSC2 expression at transcriptional level. Conclusion:Permeability of monolayer endothelial cells was enhanced by ox Lp(a) which is related to up-regulating ROS formation and down-regulating desmogleins expression.

关键词： oxidized-lipoprotein(a) reactive oxygen species permeability desmogleins superoxide dismutase

基于改进粒子群算法的新能源汽车充电站选址方法

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吉林大学学报（工学版） 2024年第8期54卷 2275-2281页

作者：张良力马晓凤武汉科技大学信息科学与工程学院武汉430081 武汉理工大学智能交通系统研究中心武汉430063

为提高汽车充电站布局的合理性,减少资源浪费,提出基于改进粒子群算法的新能源汽车充电站选址方法。预测电动汽车未来分布情况,将用户出行特征、交通密度、服务半径等因素作为选址的参考依据;以需求点到充电站间的距离最短为目标函数,... 详细信息

为提高汽车充电站布局的合理性,减少资源浪费,提出基于改进粒子群算法的新能源汽车充电站选址方法。预测电动汽车未来分布情况,将用户出行特征、交通密度、服务半径等因素作为选址的参考依据;以需求点到充电站间的距离最短为目标函数,设置相关约束条件,建立选址模型;探究经典粒子群算法的实现过程,获取粒子速度与位置更新公式;针对方法容易陷入局部最优问题,使用遗传算法对其加以改进;利用改进后的算法求解目标函数,设置初始参数和判定条件,增加粒子交叉、变异等操作,提高粒子群质量,当满足迭代次数要求时,输出个体最优位置,即充电站选址的最优方案。实验结果表明:本文方法所选的位置符合目标函数要求,令充电需求均衡,避免了资源浪费。

关键词：粒子群优化遗传算法新能源汽车充电站选址目标函数

维普期刊数据库博看期刊

整体观念下少数民族教师教育培训的“因材施教”

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贵州民族研究 2015年第3期36卷 214-217页

作者：马晓凤陕西师范大学教育学院陕西西安710062 宁夏大学教育学院宁夏银川750021

在特殊的身份地位限定下,少数民族教师形成了多重角色内涵,不同角色对应不同的职责和义务,因此少数民族教师的教育培训必须树立整体观念,首先梳理其角色构成,其次明确角色轻重,最后对重点角色展开针对性培训教育,只有这样,民族教师的教... 详细信息

在特殊的身份地位限定下,少数民族教师形成了多重角色内涵,不同角色对应不同的职责和义务,因此少数民族教师的教育培训必须树立整体观念,首先梳理其角色构成,其次明确角色轻重,最后对重点角色展开针对性培训教育,只有这样,民族教师的教育培训才能做到真正意义上的"因材施教",与教育培训推进民族教育发展、推进民族发展的最终目地达成一致。

关键词：民族教师教育培训多元文化

Highly Efficient and Economical Baculovirus Expression System for Preparing Human Papillomavirus Type16 Virus-like Particle

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 548-552页

作者： Jin ZHENG, Jun ma, xiao-feng YANG, Hong-Li LIU, Hong-Wei CHENG, Lu-Sheng SI, and Yi-Li WANGThe Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Cancer Research,School of Life Science and Technology, Xi’an Jiaotong University, Xi’an 710061, China The Key Laboratory of Biomedical Information Engineering of Ministry of Education Institute of Cancer Research School of Life Science and Technology Xi’an Jiaotong University

To improve the existing human papillomavirus type16 (HPV16) virus-like particle (VLP) preparation, a highly efficient, economical and timesaving system was established. Sf-9 cells were infected with recombinant baculovirus containing the target gene encoding HPV16L1 protein with 6×His tag, and harvested 72 h postinfection (p.i.) at 27 °C. The ProBondTM purification system was used for protein purification. The molecular weight of expressed HPV16L1 protein was 58 kD as revealed by SDS-PAGE, and confirmed by Western blot. The purity of denatured and native HPVL1 proteins that were prepared were 91.9% and 71.5%, respectively, which corresponded to a yield of 2.26 mg denatured protein and 1.84 mg native protein per 2×107 cells. The proteins were further analyzed by mouse erythrocyte hemagglutination assay and hemagglutination inhibition assay, and there effects on VLP formation were also visualized by transmission electron microscopy. Results showed that the native protein purified was biologically active as natural HPVL1 protein, inducing the murine erythrocyte agglutination and VLP formation. In addition, the purified recombinant HPV16L1 native protein with 6×His tag could self-assemble into virions in vitro. Hopefully, the present expression and purification system is promising to be convenient, timesaving and economical for preparation of HPV16 VLP vaccine.

关键词： human papillomavirus HPV16L1 protein purification virus-like particle (VLP)