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Modeling Climate Change Impacts on the US Agricultural Exports

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Journal of Integrative Agriculture 2014年第4期13卷 666-676页

作者： zhang yu-quan CAI Yong-xia Beach Robert H McCARL Bruce A Agricultural Resource & Energy Economics and Policy ProgramRTI InternationalResearch Triangle Park Department of Agricultural Economics Texas A&M UniversityCollege Station

Climate change is expected to have substantial effects on agricultural productivity worldwide. However, these impacts will differ across commodities, locations and time periods. As a result, landowners will see changes in relative returns that are likely to induce modifications in production practices and land allocation. In addition, regional variations in impacts can alter relative competitiveness across countries and lead to adjustments in international trade patterns. Thus in climate change impact studies it is likely useful to account for worldwide productivity effects. In this study, we investigate the implications of considering rest of world climate impacts on projections of the US agricultural exports. We chose to focus on the US because it is one of the largest agricultural exporters. To conduct our analyses, we consider four alternative climate scenarios, both with and without rest of world climate change impacts. Our results show that considering/ignoring rest of world climate impacts causes significant changes in the US production and exports projections. Thus we feel climate change impact studies should account not only for climate impacts in the country of focus but also on productivity in the rest of the world in order to capture effects on commodity markets and trade potential.

关键词： climate change relative competitiveness trade agricultural sector model (ASM)

Electrocatalytic Determination of Dopamine in the Presence of Ascorbic Acid by Poly-L-proline and Ferricyanide Compound Film Modified Electrode

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Chemical Research in Chinese Universities 2009年第6期25卷 827-831页

作者： CAO Yan-xiu LIU Xing-mei HUANG Hui zhang Xue-yu zhang Zhi-quan College of Chemistry Jilin University Changchun 130012 P. R. China

A novel biosensor was fabricated by the electrochemical polymerization of poly-L-proline（P-LP） and ferricyanide（FC） to form a compound film on a glassy carbon electrode（GCE）. The compound film modified electrode（P-LP/FC/GCE） shows electrocatalytic activity toward dopamine（DA） in a phosphate buffer solution（PBS, pH = 4.0） with a diminution of the overpotential and an increase in peak current. P-LP/FC/GCE was used to study the electrocatalytic oxidation of DA and ascorbic acid（AA） by means of cyclic voltammetry（CV）, differential pulse voltammetry（DPV） and amperometric i-t curve techniques. The overlapping anodic peaks of DA and AA were resolved into two well-defined voltammetric peaks in CV and DPV with the potential differences of about 200 and 225 mV, respectively. The peak current of DA is linearly change with the concentration of DA in a range of 1 × 10^-7 to 1.14 × 10^-4 mol/L with the correlation coefficient of 0.9997. The detection limit is 4.4~10-8 mol/L（S/N=3）. P-LP/FC/GCE exhibited an excellent selectivity, sensibility and stability for the determination of DA, and can be applied to the determination of dopamine injections with satisfied results.

关键词： L-Proline Ferricyanide Dopamine Modified electrode Electropolymerization

Synthesis and Study of Spectroscopic Properties of Imidazole Porphyrin and Its Zn(Ⅱ) Complex

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Chinese Journal of Structural Chemistry 2019年第7期38卷 1159-1163页

作者： GUO Guo-Zhe zhang Yan-Min zhang yu-quan ZHENG Xv-Dong LI Yan-Chun LIU Jia-Cheng Longdong University Fluobon Surfactant Engineering Technology Center College of Chemistry^& Chemical Engineering Cooperative Innovation Center of Industrial Surfactant Longdong University Qingyang 745000 China Key Laboratory of Polymer Materials of Gansu Province Key L aboratory of Bioelectrochemistry and Environmental Analysis of Gansu College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070China

A novel sensitizer with imidazole zinc porphyrin as electron donor has been synthesized. The structure has been characterized by UV-Vis, elemental analyses and 1 H ***-Vis and fluorescence spectra show that it has good light absorbing properties in the range of visible light and suggests that it has potential applications in dye-sensitized solar cells.

关键词： sensitizer imidazole porphyrin complexe synthesis

Primary Reconstruction of Completely Biologic Tissue Engineered Blood Vessel and Related Basic Research

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生物医学工程学杂志 2005年第S1期22卷 51-52页

作者： Xiu-Hua zhang Yan zhang yu-quan LI Xiang-Qun YANGLin zhang Hui-Long HUANG(Institute of Biomedical Engineering, The Second Military Medical University, Shanghai 200433,China)

Computer Controlled Polishing of the Off-axis Aspheric Mirrors

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光学精密工程 2001年第5期9卷 467-473页

作者： zhang Xue jun,WENG Zhi cheng,zhang Zhong yu, WANG quan dou,zhang Feng (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130022, China) 中科院长春光学精密机械与物理所吉林长春 1 30 0 2 2

In this paper, the manufacturing and testing procedures to make large off-axis aspherical mirrors are presented. The difficulties in polishing and testing for both circular aperture and rectangular aperture mirrors are previewed, and a possible solution is given. The two mirrors have been polished by means of CCOS, and the final accuracy is 25nm rms for 770mm×210mm rectangular mirror and 20nm rms for φ600mm circular mirror. These results just meet the optical tolerances specified by the designer, and the manufacturing and testing procedures presented here show good ability to make the large off-axis aspherical mirrors.

关键词： asphere computer-controlled polishing optical testing

基于LMDI的长江经济带交通碳排放变化分析

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中国环境科学 2022年第10期42卷 4817-4826页

作者：杨绍华张宇泉耿涌上海交通大学中英国际低碳学院上海201306 上海交通大学环境科学与工程学院上海200240

基于LMDI分解模型,探究了2000~2019年长江经济带交通运输业碳密度､运输结构､能源效率､能源强度､经济结构､经济水平以及人口规模等因素对交通碳排放的贡献程度及时空特性,并使用泰尔指数测算了碳排放的区域差异性.结果表明,经济规模持续... 详细信息

基于LMDI分解模型,探究了2000~2019年长江经济带交通运输业碳密度､运输结构､能源效率､能源强度､经济结构､经济水平以及人口规模等因素对交通碳排放的贡献程度及时空特性,并使用泰尔指数测算了碳排放的区域差异性.结果表明,经济规模持续扩张是长江经济带交通运输业碳排放增长的第一主导因素,对碳排放的正向驱动效应为116.33%,其次是人口规模(6.19%);运输结构和经济结构的转变则是抑制碳排放增长的关键因素,其负向驱动率分别为-26.18%和-16.25%;而技术水平(能源效率和能源强度)的提升有助于抑制碳排放增加.此外,基于人均碳排放和碳排放强度的泰尔指数均显示长江经济交通碳排放量的区域差异性明显,其中区域内差异大于区域间差异,且基于碳排放强度的区域差异呈现出“俱乐部趋同”现象.最后,对长江经济带交通绿色发展提出了政策建议.

关键词：交通碳排放 LMDI分解泰尔指数

中美软实力在东南亚国家中的影响比较——以“和谐世界”和“民主联盟”为中心

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厦门大学学报（哲学社会科学版） 2010年第3期60卷 73-80,113页

作者：张宇权中山大学亚太研究院广东广州510275

"和谐世界"与"民主联盟"是中美两国新近提出的外交理念。在东南亚,虽然大部分国家不清楚"和谐世界"的内涵,但却认可中国以"和谐世界"为目标所采取的举动,这无疑有助于逐步消除"中国威胁论"的担忧。而美国在东南亚的影响力虽然相对下降,... 详细信息

"和谐世界"与"民主联盟"是中美两国新近提出的外交理念。在东南亚,虽然大部分国家不清楚"和谐世界"的内涵,但却认可中国以"和谐世界"为目标所采取的举动,这无疑有助于逐步消除"中国威胁论"的担忧。而美国在东南亚的影响力虽然相对下降,但是仍然发挥着举足轻重的作用。中国应该在互动交流中让东南亚国家充分理解中国"和谐世界"的自我定位、内涵与本质,共同促进双方关系的良性发展。

关键词： “和谐世界” “民主联盟” 东南亚软实力中国美国

冠状动脉功能学评价指标在经皮冠状动脉介入术中的应用进展

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解放军医学杂志 2021年第11期46卷 1129-1135页

作者：胡强张权宇空军军医大学附属西京医院心内科西安710032 北部战区总医院心内科沈阳110016

近年来,冠状动脉功能学评价指标已用于评价病变血管生理功能、判断病变严重程度进而指导冠状动脉粥样硬化性心脏病(CHD)患者的血运重建。血流储备分数(FFR)作为一种有创的功能学指标,其有效性已被大量文献所证实,但因其具有一定局限性,... 详细信息

近年来,冠状动脉功能学评价指标已用于评价病变血管生理功能、判断病变严重程度进而指导冠状动脉粥样硬化性心脏病(CHD)患者的血运重建。血流储备分数(FFR)作为一种有创的功能学指标,其有效性已被大量文献所证实,但因其具有一定局限性,因而在FFR的基础上产生了瞬时无波形比值(iFR)、定量血流分数(QFR)等多种新型功能学评价指标。这些功能学评价指标各具特色,尽管尚未在临床上广泛应用,但对冠心病患者的血运重建具有一定的评估价值。该文主要对冠状动脉功能学评价指标的特点,FFR、iFR和QFR这三类功能学评价指标的诊断及预后评估能力、优缺点,其他新型功能学评价指标,以及功能指标临床预后评价的最新应用进展进行综述,从而指导临床在特定条件下使用特定的功能学评价指标或联合使用解剖学和功能学评价指标建立血运重建模式以减少假阳性和(或)假阴性,提高诊断的准确性。

关键词：冠状动脉粥样硬化性心脏病功能学评价指标血流储备分数瞬时无波形比值定量血流分数血运重建

我国优秀田径运动员竞技能力临场发挥的稳定性

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体育学刊 2010年第6期17卷 76-79页

作者：张玉泉聊城大学体育学院山东聊城252059

对第11届全运会田径决赛1～8名运动员竞技能力的发挥水平进行了统计分析。结果表明:参加本届比赛运动员竞技能力总体表现出较高的稳定性,发挥水平达101.09%,男女运动员的发挥基本在同一水平上,共有70.83%的运动员正常或超常发挥,29.17%... 详细信息

对第11届全运会田径决赛1～8名运动员竞技能力的发挥水平进行了统计分析。结果表明:参加本届比赛运动员竞技能力总体表现出较高的稳定性,发挥水平达101.09%,男女运动员的发挥基本在同一水平上,共有70.83%的运动员正常或超常发挥,29.17%的运动员失常发挥。男女前3名竞技能力的发挥水平明显优于4～8名,即名次愈好其竞技能力发挥水平愈高。不同亚类项群及其分组项目运动员竞技能力的发挥水平具有鲜明的项群特征,发挥水平依大小排序为:耐力性>综合性>速度性>快速力量性;中长距离>超常距离>全能>短跨>跳跃>投掷。耐力性项群竞技能力的发挥最为稳定,快速力量性项群发挥的稳定性最差。不同年龄运动员发挥水平存在着显著差异,而处于最佳竞技发展稳定阶段(24～30岁)的运动员临场发挥具有较高的稳定性。

关键词：训练与竞赛竞技能力临场发挥竞技能力发挥稳定性田径运动员