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Responses of Plant Community and Soil Properties to Inter-Annual Precipitation Variability and Grazing Durations in a Desert Steppe in Inner Mongolia

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Journal of Integrative Agriculture 2014年第6期13卷 1171-1182页

作者： wang Zhen yun Xiang-jun WEI Zhi-jun Michael P Schellenberg wang yun-feng YANG Xia HOU Xiang-yang Grassland Research Institute Chinese Academy of Agricultural Sciences Department of Grassland Science College of Ecology and Environmental ScienceInner Mongolia Agricultural University Semiarid Prairie Agricultural Research Center (SPARC) Agriculture and Agri-Food Canada

Grazing can dramatically affect arid grassland communities that are very vulnerable to environmental changes due to its relatively short and sparse ground coverage, low biomass, sandy soil and inter-annual precipitation found in the desert steppe. The study investigates the effects of different grazing durations on vegetation and soil properties of a desert steppe community. The experiment was conducted in Xisu Banner in Inner Mongolia with ifve treatments：CG （continuous grazing）, 40UG （40 d ungrazed）, 50UG （50 d ungrazed）, 60UG （60 d ungrazed） and UG （ungrazed）. The biomass of both shrub and annual-biennial plant communities were signiifcantly decreased by CG. Continuous grazing and 40UG signiifcantly reduced the ANPP （aboveground net primary productivity） by the end of the three year study. 60UG treatment increased soil organic carbon （OC）, total nitrogen concentration （TN） and total phosphorus concentration （TP） concentrations and 50UG increased the TN and total phosphorus concentration （TK） concentrations, whereas CG, 40UG and 50UG decreased soil OC, TP and available phosphorus concentration （AP） concentrations. The perennial plant species of the desert steppe were generally tolerant for grazing. The annual-biennial plant species had large variability in ANPP because of the inter-annual precipitation. Our results highlight that inter-annual precipitation variations could strongly modify the community responses to grazing in arid ecosystems.

关键词： ANPP plant species plant fimctional group soil nutrient

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A Study on Molybdenite Electronic Structure

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Chemical Research in Chinese Universities 1995年第4期11卷 306-311页

作者： LONG Xiang-yun and wang feng-zhen (Dept .of Chem.,Central South University of Technology, Changshaha 410083) CENT S UNIV TECHNOL DEPT CHEMCHANGSHA 410083PEOPLES R CHINA

he present paper covers thedectronic structure of Molybdenite(MoS_2)with layer structure studied using tight-binding energy band structure calculation and localization molecular orbital CNDO/2 method,and the bonding c... 详细信息

关键词： Molybdenite Band structure Electronic structure

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Assessment on Dietary Melamine Exposure from Tainted Infant Formula

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Biomedical and Environmental Sciences 2009年第2期22卷 100-103页

作者： XU-DONG JIA NING LI ZHU-TIAN wang yun-feng ZHAO YONG-NING WU AND WEI-XING YAN Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective To estimate the dietary melamine exposure in Chinese infants and young children from the consumption of melamine adulterated Sanlu infant formula. Methods Four age groups of infants and young children （3, 6, 12, and 24 months） were chosen as the assessed subjects and the maximum amount of infant formula consumption was estimated based on the recommended usage level in the package insert of Sanlu infant formula and other brands. Melamine was analyzed in 111 Sanlu infant fbrmula samples collected from the markets in Beijing and Gansu province using the LC-MS-MS with a limit of quantification of 0.05 mg/kg. Four levels of melamine concentration were chosen to estimate the dietary intakes, including the mean, median, 90th percentile, and maximum. Results The infants of 3 months had the highest intake of melamine, and with the increase of the age （inonth）, the intake decreased. Based on the median melamine concentration （1 000 mg/kg） as an example, the melamine intakes fur the infants of 3, 6, 12, and 24 months were 23.4, 21.4, 15.0, and 8.6 mg/kg bw/d, respectively. Conclusion Dietary melamine intakes from tainted Sanln infant formula significantly exceeded the TDI level （0.2 mg/kg bw/d） recommended by the WHO Expert Meeting in 2008. However, the present assessment has some limitations including the poor representative samples, the varied melamine concentrations in the adulterated Sanlu infant formula, and other brand infant formula possibly consumed by these infants.

关键词： Dietary exposure assessment Melamine Infant formula

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A Preparation Model of Chinese Medicine Decoction Placebo

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Chinese Journal of Integrative Medicine 2017年第8期23卷 631-634页

作者： BIAN Li-qun LI Bao-shuang LI Zhen-hua wang feng-yun WEN Yan-dong TANG Xu-dong Department of Gastroenterology Xiyuan Hospital China Academy of Chinese Medical Sciences Beijing 100091 China

Chinese medicine（CM）decoction placebo is one of the key factors restricting the placebo-controlled clinical trial of *** this article,based on the analysis of the difficulties in preparing CM placebo,the production requirements for placebo were put ***,in accordance with clinical practices,a production method and evaluation process of CM decoction placebo was proposed,to provide a reference for clinical research.

关键词： placebo decoction Chinese medicine preparation model

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BMI and BMI Changes to All-cause Mortality among the Elderly in Beijing： a 20-year Cohort Study

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Biomedical and Environmental Sciences 2017年第2期30卷 79-87页

作者： wang yun feng TANG Zhe GUO Jin TAO Li Xin LIU Long LI Hai Bin LI Di Tian GUO Xiu Hua YANG Xing Hua School of Public Health Capital Medical University Beijing 100069 China Beijing Municipal Key Laboratory of Clinical Epidemiology Beijing 100069 China School of Basic Medical Sciences Peking University Health Science Center Beijing 100191 China School of Basic Medical Sciences Peking University Health Science Center Beijing100191 China

Objective To explore the association between body mass index （BMI） and all-cause mortality among the elderly in Beijing. Methods This analysis was based on the Beijing multidimensional longitudinal study of aging （BLSA）, which included 2,090 subjects over 55 years old and was followed-up from 1992 to 2012. BMI-mortality curves were drawn to find the optimal BMI range with the lowest mortality. Cox proportional hazard models were used to obtain the hazard ratios （HRs） for BMI and BMI changes in the overall population and in specific stratified populations. Results During follow-up, 2,264 deaths were recorded; BMI-mortality curve was U-shaped, with the lowest mortality at a BMI of approximately 25 kg/m2. After adjusting for gender, age, smoking, drinking and some pre-existing diseases, HRs for underweight, overweight and obesity compared with normal weight were 2.372 （95% C/： 2.254-2.632）, 0.767 （95% CI： 0.666-0.884） and 0.872 （95% CI： 0.830-1.246）, respectively. HR for BMI drop was 3.245 （95% CI： 0.824-22.772） in the underweight group and 1.892 （95% C/： 0.830-1.246） in the normal weight group, HR for BMI rise was 1.795 （95% CI： 1.243-2.591） in normal weight group and 2.962 （95% CI： 2.202-3.203） in the overweight group. Conclusion Keeping BMI in an overweight status and stable is related to a reduced mortality

关键词： Body mass index All-cause mortality The elderly Beijing

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Ion mechanism of isoproterenol on delayed afterdepolarization and triggered activity in the infarcted ventricle

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Journal of Geriatric Cardiology 2010年第3期7卷 180-183页

作者： Jin-Liao Gao Hong-Juan wang yun-feng Lan Zhou Fang Yan Liu Min Lin Yi-Cheng Fu Yang Li Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

Objectives This study aimed at investigating the cellular mechanism of isoproterenol （ISO） on delayed afterdepolarizations （DADs） and triggered activity （TA） of the noninfarcted myocardium in the myocardial infarcted rabbit *** Rabbits with the left anterior descending coronary artery occlusion were prepared and recovered for 8 wk （healed myocardial infarction, HMI）. Myocytes were isolated from regions of the noninfarcted left ventricular free wall. ISO was added to cellular surface by perfusion way. Action potentials and ion currents were recorded with whole-cell patch clamp. Results The results showed that treatment with ISO induced more DADs and TA events in HMI myocytes. Iti and IC,_L of myocytes treated with ISO were increased significantly compared with HMI cells, which contributed to DADs-related triggered arrhythmia. Conclusions The results suggested that more arrhythmia events of DADs and TA developed in myocytes with ISO treatment. The underlying mechanism was associated with the augment of I6 and calcium influxing

关键词： isoproterenol healed myocardial infarction delayed afterdepolarization triggered activity ion channels

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IEEE 802.16无线信道快速突发均衡的实现

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电子科技大学学报 2005年第2期34卷 179-182页

作者：孙长印王云峰王允宽西安电子科技大学雷达信号处理重点实验室西安710071 中兴通讯股份有限公司西安710065

针对IEEE 802.16无线信道进行了仿真,提出了一种工作于该信道的16QAM突发模式的快速均衡器算法,该算法采用Neuman-Hoffman序列的扩展序列进行信道快速估计,及用均衡器系数预加载算法以提高收敛速度,仿真结果证明:算法收敛速度优于递归... 详细信息

针对IEEE 802.16无线信道进行了仿真,提出了一种工作于该信道的16QAM突发模式的快速均衡器算法,该算法采用Neuman-Hoffman序列的扩展序列进行信道快速估计,及用均衡器系数预加载算法以提高收敛速度,仿真结果证明:算法收敛速度优于递归最小二乘算法。

关键词：宽带无线接入判决反馈均衡器仿真信道估计系数预加载

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小型航天器微振动主动控制平台建模与仿真

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振动与冲击 2013年第22期32卷 140-145页

作者：王云峰程伟北京航空航天大学航空科学与工程学院北京100191

为克服动量轮等旋转装置微振动对航天器指向精度等影响,制作连接旋转装置及星体的小型微振动主动控制装置,通过四个主动压电折叠梁实现微振动主动控制;利用有限元理论建立微振动主动控制平台及旋转装置动力学模型并进行动力学性能分析;... 详细信息

为克服动量轮等旋转装置微振动对航天器指向精度等影响,制作连接旋转装置及星体的小型微振动主动控制装置,通过四个主动压电折叠梁实现微振动主动控制;利用有限元理论建立微振动主动控制平台及旋转装置动力学模型并进行动力学性能分析;使用线性二次Gauss(LQG)方法设计控制率,对控制系统在正弦激励及初始位移两种载荷工况下的主动控制效果仿真研究。结果显示此微振动主动控制平台能有效抑制系统振动。

关键词：微振动主动控制压电线性二次Gauss控制仿真

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RDX晶体形貌的分子模拟与预测

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含能材料 2013年第5期21卷 583-588页

作者：陈刚王风云南京理工大学工业化学研究所江苏南京210094

用BFDH(Bravais-Friedel-Donnary-Harker)和AE(Attachment Energy)模型预测了α晶形黑索今(α-RDX)的晶体形貌。结果表明,形态学上重要生长面是:(111),(020),(002),(200)和(210)面,其中(111)面是最重要的生长面。RDX晶体重要生长面结构分析表明,(210),(002),(200)和(111)是极性晶面,而(020)是非极性晶面,其中(210)晶面极性最强。根据晶面极性预测在极性溶剂中,(210)面将成为RDX晶体形态上重要生长面,(111)面的重要性降低,而(020)面将会在晶体生长过程中逐渐消失。丙酮溶剂重结晶RDX实验表明,RDX晶体形貌上最终显露的生长面是:(210),(111),(002)和(200)面,而(020)面已消失。

关键词：物理化学 RDX 晶体形貌 BFDH模型 AE模型晶面结构

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管理理论的生命力和实用价值——兼论其时代性与时代化

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管理科学学报 2019年第4期22卷 14-15页

作者：王云峰河北工业大学经济管理学院

管理理论是科学理论的一个门类.理论,其本质是人类思想和认知的发展,有经典和非经典的区别.经典理论其开创者有超凡的认知能力,思想深邃,成果具有较高的传承价值和较强的生命力.因而,管理理论研究,无论是经典理论的演绎或实践规律的发... 详细信息

管理理论是科学理论的一个门类.理论,其本质是人类思想和认知的发展,有经典和非经典的区别.经典理论其开创者有超凡的认知能力,思想深邃,成果具有较高的传承价值和较强的生命力.因而,管理理论研究,无论是经典理论的演绎或实践规律的发掘形成学说,其价值和前途均取决于管理思想阐释和思辨的功夫.

关键词：经典理论管理理论层次性

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