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高效稳定的单一汞同位素大气发生系统

地球与环境 2014年第3期42卷 413-418页

作者：颜紫云冯新斌 che-jen lin 王衡王训中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550002 贵州大学资源与环境工程学院贵阳550002 Lamar大学土木工程学院

汞在大气-植被-土壤界面间的迁移转化一直是近年来研究的热点,稳定汞同位素添加技术为这一科学问题的研究提供了新的手段,而如何产生低浓度、稳定、连续且经济可行的单一汞同位素大气(xxx Hg0)是试验研究的难点与关键。本试验旨在设计... 详细信息

汞在大气-植被-土壤界面间的迁移转化一直是近年来研究的热点,稳定汞同位素添加技术为这一科学问题的研究提供了新的手段,而如何产生低浓度、稳定、连续且经济可行的单一汞同位素大气(xxx Hg0)是试验研究的难点与关键。本试验旨在设计、创建微环境单一汞同位素富集大气的发生系统,该系统不仅具有低成本,可以连续产生低浓度、稳定性强、可控性高、利用效率高的同位素汞蒸气(xxx Hg0)特性,还兼有轻便灵巧、安装便捷、可移动性强和适用范围广等特点。

关键词： Hg同位素示踪技术大气汞同位素添加系统

Virtual Power Plants for Grid Resilience: A Concise Overview of Research and Applications

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 329-343页

作者： Yijing Xie Yichen Zhang Wei-jen Lee Zongli lin Yacov A.Shamash IEEE Department of Electrical Engineering University of Texas at ArlingtonArlingtonTX 76019 USA Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904 USA Department of Electrical and Computer Engineering Stony Brook UniversityStony BrookNY 11794 USA

The power grid is undergoing a transformation from synchronous generators(SGs) toward inverter-based resources(IBRs). The stochasticity, asynchronicity, and limited-inertia characteristics of IBRs bring about challenges to grid resilience. Virtual power plants(VPPs) are emerging technologies to improve the grid resilience and advance the transformation. By judiciously aggregating geographically distributed energy resources(DERs) as individual electrical entities, VPPs can provide capacity and ancillary services to grid operations and participate in electricity wholesale markets. This paper aims to provide a concise overview of the concept and development of VPPs and the latest progresses in VPP operation, with the focus on VPP scheduling and control. Based on this overview, we identify a few potential challenges in VPP operation and discuss the opportunities of integrating the multi-agent system(MAS)-based strategy into the VPP operation to enhance its scalability, performance and resilience.

关键词： Climate change renewable energy resources resilience smart grids virtual power plants(VPPs)

The Potential Game-Changer:A Concept-to-Proof Study on D:A Heterojunction-Free Organic Photovoltaics

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Chinese Journal of chemistry 2024年第3期42卷 252-258页

作者： Lijian Zuo Sae Byeok Jo Xueliang Shi Francis lin Alex jen State Key Laboratory of Silicon and Advanced Semiconductor Materials MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang310058 China Department of Materials Science and Engineering University of WashingtonSeattleWAUSA School of chemical Engineering Sungkyunkwan University (SKKU)Suwon16419 Republic of Korea School of chemistry and Molecular Engineering East China Normal UniversityShanghai200062 China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Department of chemistry City University of Hong KongKowloonHong KongChina Hong Kong Institute for Clean Energy Hong KongChina

Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.

关键词： Organic solar cells Spontaneous charge generation Ambipolar charge transport Charge recombination Perovskite-like organic semiconductor Schottky-junction structure Single component

基于响应面模型的区域大气污染控制辅助决策工具研发

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环境科学学报 2012年第8期32卷 1913-1922页

作者：劳苑雯朱云 Carey Jang che jen lin 邢佳陈志润谢俊平王书肖 Joshua Fu 华南理工大学环境科学与工程学院广东省大气环境与污染控制重点实验室 USEPA/Office of Air Quality Planning & Standards RTPNC27711USA Department of Civil Engineering Lamar UniversityBeaumontTX 77710-0024USA 清华大学环境学院 Department of Civil & Environmental Engineering University of TennesseeKnoxvilleTN 37996-2010USA

基于CMAQ模型结果,利用高维克里金插值算法,建立了排放控制因子与污染物环境浓度的响应面模型(RSM),实现了大气污染可控源排放与复合污染水平的实时函数响应.研究结果显示,RSM对PM2.5的预测结果与CMAQ实际模拟结果的误差在容许范围内(... 详细信息

基于CMAQ模型结果,利用高维克里金插值算法,建立了排放控制因子与污染物环境浓度的响应面模型(RSM),实现了大气污染可控源排放与复合污染水平的实时函数响应.研究结果显示,RSM对PM2.5的预测结果与CMAQ实际模拟结果的误差在容许范围内(最大误差小于0.20μg.m-3,3.89%).基于所建立的RSM,开发了RSM-VAT区域大气污染控制可视化辅助决策工具.使用RSM-VAT对美国8个典型城市的PM2.5污染状况进行了控制情景分析,通过"可视化展示"和"图表分析"二大模块,输出不同控制情景下的环境污染物浓度的实时响应图、可视化展示和数据分析图表等结果.

关键词：大气污染控制响应面模型辅助决策工具模型数据可视化

基于测点环境浓度影响的点源应急强化减排分析

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环境科学学报 2014年第8期34卷 1912-1921页

作者：谢颖斯朱云许嘉钰曾燕君贺克斌 che-jen lin 李敏辉范丽雅华南理工大学环境与能源学院广东省大气环境与污染控制重点实验室清华大学环境学院广州市环境监测中心站 Department of Civil Engineering Lamar UniversityBeaumontTX 77710-0024USA

基于预报气象条件、广州及周边城市的重点企业排放清单,采用CALPUFF模型模拟2010年亚运会开幕式期间重点企业对广州市内空气质量监测点的相对环境浓度影响,据此筛选得出预报不利气象条件下工业点源应急强化减排名单,并利用GIS可视化技... 详细信息

基于预报气象条件、广州及周边城市的重点企业排放清单,采用CALPUFF模型模拟2010年亚运会开幕式期间重点企业对广州市内空气质量监测点的相对环境浓度影响,据此筛选得出预报不利气象条件下工业点源应急强化减排名单,并利用GIS可视化技术分析点源强化减排效果,为空气质量保障的专家会商提供依据.广州亚运会期间点源应急强化减排实施效果表明,有针对性地对测点环境浓度影响大的企业实施强化减排措施,可有效缓解个别点位的一定范围内超标问题.本文提出的研究方法和配套的GIS软件可为不利气象条件下工业点源的应急强化减排提供辅助决策服务和数据支持.

关键词：工业点源空气质量应急强化减排大气污染模拟辅助决策

Cross-border E-commerce and China's Exports during the COVID-19 Pandemic

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China & World Economy 2024年第3期32卷 215-242页

作者： Yi che Meng Yuan Yan Zhang lin Zhao School of Business East China University of Science and TechnologyChina School of Business Xiangtan UniversityChina School of Economics Shanghai University of Finance and EconomicsChina

China's exports experienced a rapid recovery after the outbreak of the 2019 COVID-19 pandemic.A primary engine was cross-border e-commerce(CBEC)trade,which bucked the downward export trend during the *** exploring the variation in the number of CBEC comprehensive pilot zones across provinces,we identified the causal impact of CBEC on exports using monthly province-product-destination data for 2019 and *** found strong and robust evidence that CBEC contributed to exports during the pandemic by promoting the expansion of incumbent exports(intensive margin)rather than through the expansion of product categories and exporting partners(extensive margin).Specifically,higher pandemic risk suppressed the role of CBEC at the intensive margin while enhancing it at the extensive *** to developed countries benefited more from CBEC,both intensively and *** with final products,a larger number of intermediate products were exported through CBEC after the outbreak of the pandemic.

关键词： China's exports COVID-19 pandemic cross-border e-commerce extensive margin of trade intensive margin of trade

空气污染与健康效益评估工具BenMAP CE研发

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环境科学学报 2013年第9期33卷 2395-2401页

作者：杨毅朱云 Carey Jang 谢俊平王书肖 Joshua Fu che-jen lin 马杰丁点邱雪珍劳苑雯华南理工大学环境与能源学院广东省大气环境与污染控制重点实验室广州510006 USEPA/Office of Air Quality Planning&Standards RTPNC27711USA Department of Civil&Environmental Engineering University of TennesseeKnoxvilleTN 37996-2010USA 清华大学环境学院北京100084 Department of Civil Engineering Lamar UniversityBeaumontTX 77710-0024USA

为了评估空气污染带来的健康冲击、评估健康效益,克服现有评估工具(BenMAP V4.0)计算速度缓慢及用户体验较差等问题,受美国环保署委托,设计并研发了新一代空气污染与健康效益评估工具BenMAP CE,搭建了BenMAP CE的框架,进行了详细功能设... 详细信息

为了评估空气污染带来的健康冲击、评估健康效益,克服现有评估工具(BenMAP V4.0)计算速度缓慢及用户体验较差等问题,受美国环保署委托,设计并研发了新一代空气污染与健康效益评估工具BenMAP CE,搭建了BenMAP CE的框架,进行了详细功能设计,并利用美国环保署提供的数据进行了实测.测试结果表明,基于相同的输入文件和设置,BenMAP CE能重现BenMAP V4.0的计算结果,相比现有的评估工具,BenMAP CE具有良好的用户体验、强大的GIS展示功能及大幅提高的计算速度.BenMAP CE是考虑了污染物环境浓度削减、人口密度、收入差异等经济因素的综合性评估工具,能为决策者评估空气污染控制措施所带来的健康效益提供辅助决策依据.

关键词：空气污染健康效益评估工具辅助决策

A long-term daily gridded snow depth dataset for the Northern Hemisphere from 1980 to 2019 based on machine learning

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Big Earth Data 2024年第2期8卷 274-301页

作者： Yanxing Hu Tao che Liyun Dai Yu Zhu lin Xiao Jie Deng Xin Li Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina Yunnan Key Laboratory of International Rivers and Transboundary Eco-Security Institute of International Rivers and Eco-SecurityYunnan UniversityKunmingChina National Forestry and Grassland Administration Key Laboratory of Forest Resource Conservation and Ecological Safety on the Upper Reaches of the Yangtze River Sichuan Province Key Laboratory of Ecological Forestry Engineering on the Upper Reaches of the Yangtze RiverCollege of ForestrySichuan Agricultural UniversityChengduChina

A high-quality snow depth product is very import for cryospheric science and its related *** long time-series snow depth products covering the Northern Hemisphere can be divided into two categories:remote sensing snow depth products and reana-lysis snow depth ***,existing gridded snow depth products have some *** sensing-derived snow depth products are temporally and spatially discontinuous and tend to underestimate snow depth,while reanalysis snow depth products have coarse spatial resolutions and great *** overcome these problems,in our previous work we proposed a novel data fusion framework based on Random Forest Regression of snow products from Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E),Advanced Microwave Scanning Radiometer-2(AMSR2),Global Snow Monitoring for Climate Research(GlobSnow),the Northern Hemisphere Snow Depth(NHSD),ERA-Interim,and Modern-Era Retrospective Analysis for Research and Applications,ver-sion 2(MERRA-2),incorporating geolocation(latitude and longitude),and topographic data(elevation),which were used as input indepen-dent *** than 30,000 ground observation sites were used as the dependent variable to train and validate the model in different time *** fusion framework resulted in a long time series of continuous daily snow depth product over the Northern Hemisphere with a spatial resolution of 0.25°.Here,we compared the fused snow depth and the original gridded snow depth products with 13,272 observation sites,showing an improved precision of our *** evaluation indices of the fused(best original)dataset yielded a coeffi-cient of determination R2 of 0.81(0.23),Root Mean Squared Error(RMSE)of 7.69(15.86)cm,and Mean Absolute Error(MAE)of 2.74(6.14)*** of the bias(88.31%)between the fused snow depth and in situ observations was in the range of−5 cm to 5 *** accuracy assessment of independent snow observation sites-Sodank

关键词： Snow depth datasets machine learning data fusion Northern Hemisphere

Application of neutrophil-lymphocyte ratio and red blood cell distribution width in diabetes mellitus complicated with heart failure

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World Journal of Diabetes 2024年第6期15卷 1226-1233页

作者： Jie Pang lin-Yan Qian Ping Lv Xiao-Ru che Heart Center Department of Cardiovascular MedicineZhejiang Provincial People’s Hospital(The Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina

BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular *** To explore the value of the combined determination of the neutrophil-lymphocyte ratio(NLR)and red blood cell distribution width(RDW)in the early diagnosis and prognosis evaluation of DM complicated with heart failure(HF).METHODS We retrospectively analyzed clinical data on 65 patients with type 2 DM(T2DM)complicated with HF(research group,Res)and 60 concurrent patients with uncomplicated T2DM(control group,Con)diagnosed at Zhejiang Provincial People’s Hospital between January 2019 and December *** NLR and RDW values were determined and comparatively analyzed,and their levels in T2DM+HF patients with different cardiac function grades were *** receiver operating characteristic(ROC)curves were plotted to determine the NLR and RDW values(alone and in combination)for the early diagnosis of *** correlation between NLR and RDW with the presence or absence of cardiac events was also *** Higher NLR and RDW levels were identified in the Res vs the Con groups(P<0.05).The NLR and RDW increased gradually and synchronously with the deterioration of cardiac function in the Res group,with marked differences in their levels among patients with grade II,III,and IV HF(P<0.05).ROC curve analysis revealed that NLR combined with RDW detection had an area under the curve of 0.915,a sensitivity of 76.9%,and a specificity of 100%for the early diagnosis of ***,HF patients with cardiac events showed higher NLR and RDW values compared with HF patients without cardiac *** NLR and RDW were useful laboratory indicators for the early diagnosis of DM complicated with HF,and their joint detection was beneficial for improving diagnostic ***,NLR and RDW values were directly proportional to patient outcomes.

关键词： Neutrophil-lymphocyte ratio Red blood cell distribution width Type 2 diabetes Heart failure Early diagnosis