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Plant community succession in modern Yellow River Delta, China

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第8期8卷 540-548页

作者： ZHANG Gao-sheng wang Ren-qing song Bai-min Institute of Ecology and Biodiversity School of Life Sciences Shandong University Ji＇nan 250100 China

Data were collected in different successional stages using a simultaneous sampling method and analyzed through quantitative classification method. Three large groups and 12 classes were made to represent the community patterns of three succession stages and 12 succession communities. The succession series of plant community in the study area was as follows: saline bare land→community Suaeda salsa→community Tamarix chinensis→grassland. Succession degree and succession process of 12 succession communities were calculated. Most of these communities were in the lower succession stage, however, community Phragmites communis+Glycine soja and community Imperata cylindrica+G. soja were close to the succession stage of grassland climax. Five species diversity indices were used to study the changes in species richness, species evenness and diversity during succession of community. Heterogeneity index and richness index increased gradually during the community succession process, but species evenness tended to decrease with succession development. The relation between succession and environment was studied by ordination technique, and the results showed that the soil salt content was an important factor to halarch succession of the modern Yellow River Delta. It affected community structure, species composition and succession process.

关键词： Community succession DCA and TWINSPAN analysis Yellow River Delta

Shock Compression of the New 47Zr45Ti5Al3V Alloys up to 200GPa

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Chinese Physics Letters 2013年第6期30卷 165-168页

作者： ZHANG Pin-Liang GONG Zi-Zheng JI Guang-Fu wang qing-song song Zhen-Fei CAO Yan wang Xiang Key Laboratory of Advanced Technologies of Materials of Ministry of Education School of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031 National Key Laboratory of Science and Technology on Reliability and Environment Engineering Beijing Institute of Spacecraft Environment EngineeringBeijing 100094 Laboratory for Shock Wave&Detonation Physics Research Institute of Fluid PhysicsChina Academy of Engineering Physics(CAEP)Mianyang 621900

Shock compression experiments on a new kind of 47Zr45Ti5Al3V alloys at pressures between 28 and 200 GPa are performed using a two-stage light gas *** Hugoniot data are obtained by combining the impedance-match method and the electrical probe *** relationship between the shock wave velocity Us and particle velocity up can be described linearly by U_(s)=4.324(±0.035)+1.177(±0.012)*** obvious evidence of phase transition is found in the shock compression pressure *** calculated U_(s)-up relationship obtained from the additive principle is different from the experimental data,indicating that theα→βphase transition occurs below 28 *** Grüneisen parameterγobtained from the experimental data can be expressed byγ=1.277(ρ0/ρ).The zero-pressure bulk modulus B0s=97.96 GPa and its pressure derivative B_(0s)=*** P–V–T equation of state for 47Zr45Ti5Al3V is given using the Vinet equation of state to describe the cold curve and the Debye model for the thermal contributions.

关键词： technique. alloys transition

Design, Synthesis, and Activities of Novel Derivativesof Isophthalamide and Benzene-1,3-disulfonamide

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Chemical Research in Chinese Universities 2006年第3期22卷 356-359页

作者： LIU Xiu-jie wang song-qing ZHANG jing ZHANG Feng-xia LI Gui-zhu wang Bao-jie SHAO Ying-lu ZHANG Li-guang FANG Lin CHENG Mao-sheng The College of Pharmaceutical Engineering Shenyang Pharmaceutical University Shenyang 110016 P.R. China The College of Pharmaceutical and Biotechnology Tianjin University Tianjin 300072 P. R. China The School of Biology and Chemistry Tianjin University of Technology Tianjin 300191 P. R. China

Based on the antiplatelet aggregation mechanism and the bioisosterism principle of the reference drug picotamide, thirteen novel derivatives of arylamide and arylsulfonamide were designed and prepared. The biological activities of these derivatives were investigated. The chemical structures of the target compounds were confirmed by ^1H NMR and IR. The in vitro activities of antiplatelet aggregation of the thirteen target compounds were assessed by Bore＇s method. Compounds 2b and 8h have significant antiplatelet aggregation activities, which are superior to the corresponding activity of Picotamide.

关键词： Thromboxane Antiplatelet Isophthalamide Disulfonamide Synthesis

A new three-phase 5-level current-source inverter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 1973-1978页

作者： BAO Jian-yu BAI Zhi-hong wang qing-song ZHANG Zhong-chao School of Electrical Engineering Zhejiang University Hangzhou 310027 China

The new three-phase 5-level current-source inverter (CSI) proposed in this paper was developed by connecting three separate single-phase 5-level CSIs in series, and its operational principle was analyzed. There are two major problems existing in current-source multilevel inverters, one is the complex PWM control method (2-logic to 3-logic conversion), and the other is the problem of current-unbalance between different levels. A simple current-balance control method via DC current feedback is applied in each single-phase 5-level CSI cell to implement the current-balance control between different levels. And to reduce the output current harmonics, POD PWM control technique was used. Simulation and experimental results showed that this new three-phase 5-level CSI topology operates correctly.

关键词： Three-phase Current-source inverter (CSI) 5-level Harmonics POD PWM

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行政体制转型与经济发展方式转变

安徽师范大学学报（社会科学版） 2010年第6期38卷 621-625页

作者：汪青松 qing-song 中共安徽农业大学委员会合肥230036

以行政体制转型促经济发展方式转变,政府经济职能必须由"越位"处"退位",从无限政府转为有限政府,履行好经济调节职能;政府宏观调控职能必须变"弱位"为"强位",从全能政府转为责任政府,履行好市场监管的职责;政府社会管理职能必须变"缺位"... 详细信息

以行政体制转型促经济发展方式转变,政府经济职能必须由"越位"处"退位",从无限政府转为有限政府,履行好经济调节职能;政府宏观调控职能必须变"弱位"为"强位",从全能政府转为责任政府,履行好市场监管的职责;政府社会管理职能必须变"缺位"为"到位",从管制政府转为服务政府,加强公共服务;政府四个职能的"错位"考核必须"正位",从人治政府转为法治政府,树立和落实正确的政绩观,使我国真正走上创新驱动、内生增长的又好又快的发展轨道。

关键词：行政体制转型经济发展方式转变 Economic Development 政府社会管理职能政府经济职能宏观调控职能树立和落实责任政府有限政府无限政府市场监管人治政府全能政府内生增长履行管制政府公共服务服务政府

基于临界渗透速度分布特性的地下水源热泵变流量运行研究

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中南大学学报（自然科学版） 2012年第12期43卷 4772-4777页

作者：王松庆张旭东北林业大学土木工程学院黑龙江哈尔滨150040 同济大学机械工程学院上海200092

基于临界渗透速度分布特性,对比分析研究地下水源热泵采用定流量和变流量运行方式对含水层参数变化特性的影响。通过案例研究分析空调负荷特性与临界渗透速度分布特性对地下水源热泵不同运行方式的影响。研究结果表明:与地下水源热泵采... 详细信息

基于临界渗透速度分布特性,对比分析研究地下水源热泵采用定流量和变流量运行方式对含水层参数变化特性的影响。通过案例研究分析空调负荷特性与临界渗透速度分布特性对地下水源热泵不同运行方式的影响。研究结果表明:与地下水源热泵采用定流量运行方式相比,采用变流量运行方式对含水层参数的影响较小,是一种可靠性较高的运行方式。如果考虑临界渗透速度分布特性的影响,采用变流量运行方式可靠性优势更为显著。

关键词：临界渗透速度地下水源热泵变流量

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电流馈电式半桥荧光灯镇流器的建模及设计

电机与控制学报 2015年第9期19卷 40-45页

作者：王青松程明东南大学电气工程学院江苏南京210096

针对电流馈电式半桥荧光灯电子镇流器的产品设计过程无理论可循、仅仅依靠工程经验试凑参数的问题,探讨了镇流器稳态运行时影响灯管寿命的关键因素,基于等效分析法和相量法建立了拓扑的等效模型并推导了相关公式,提出了电路中关键元件... 详细信息

针对电流馈电式半桥荧光灯电子镇流器的产品设计过程无理论可循、仅仅依靠工程经验试凑参数的问题,探讨了镇流器稳态运行时影响灯管寿命的关键因素,基于等效分析法和相量法建立了拓扑的等效模型并推导了相关公式,提出了电路中关键元件参数的理论计算方法。在不改变电路拓扑的情况下,通过优化设计电路参数,可在保证系统原有性能的基础上进一步减小灯电流的波峰系数(crest factor,CF),通过仿真及实验验证了所建模型及理论计算的准确性,最后通过对比说明经建模后得出的新参数使得灯电流的CF低于原设计,从而有效缓解灯电流对灯管寿命的影响,提高了系统的可靠性。

关键词：拓扑建模参数设计荧光灯电子镇流器电流馈电式波峰系数

地下水源热泵定压差取水方式对含水层渗透性的影响

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中南大学学报（自然科学版） 2011年第6期42卷 1624-1628页

作者：王松庆张旭同济大学机械工程学院上海200092

针对地下水源热泵取水引起含水层颗粒迁移问题建立数学模型,并通过案例计算分析地下水源热泵定压差取水方式对含水层渗透性的影响。研究结果表明,地下水源热泵运行5 a后含水层厚度为20,25和30 m时的孔隙率依次增大到初始值的2.57,1.86和... 详细信息

针对地下水源热泵取水引起含水层颗粒迁移问题建立数学模型,并通过案例计算分析地下水源热泵定压差取水方式对含水层渗透性的影响。研究结果表明,地下水源热泵运行5 a后含水层厚度为20,25和30 m时的孔隙率依次增大到初始值的2.57,1.86和1.59倍,渗透系数依次增大到初始值的156,16和7倍;考虑颗粒迁移时,地下水源热泵定压差取水方式对含水层渗透性影响显著。

关键词：地下水源热泵定压差含水层渗透性

地下水源热泵不同运行方式对含水层参数影响分析

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湖南大学学报（自然科学版） 2011年第7期38卷 64-68页

作者：王松庆张旭同济大学机械工程学院上海200092

通过案例计算,分别对地下水源热泵采用定流量和定压差2种运行方式对含水层参数变化特性的影响进行研究.研究结果表明,与地下水源热泵采用定流量运行方式相比,采用定压差运行方式时含水层孔隙率和渗透系数平均增大率分别为0.45%和2.07%,... 详细信息

通过案例计算,分别对地下水源热泵采用定流量和定压差2种运行方式对含水层参数变化特性的影响进行研究.研究结果表明,与地下水源热泵采用定流量运行方式相比,采用定压差运行方式时含水层孔隙率和渗透系数平均增大率分别为0.45%和2.07%,采用定压差运行方式对含水层参数变化特性的影响程度大于定流量运行方式.对于完整井,增大取水井井径和含水层厚度会使2种运行方式对含水层参数变化特性的影响减弱.

关键词：地下水源热泵运行方式含水层参数