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A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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Science China(Technological Sciences) 2004年第Z1期47卷 60-71页

作者： wang Zhonggen1. ZHENG Hongxing1.{1., , WU Xianfeng2.2.& ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, {2. 1.01.1. China 2. Institute of Environmental Science, {2. normal university, beijing 100875, China 3. Water Resources Conservation Committee of Yellow River, Zhengzhou 450003, China Key Laboratory of Water Cyde & Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Environmental Science Beijing Normal University Beijing China Water Resources Conservation Committee of Yellow River Zhengzhou China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1.96 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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Science China(Information Sciences) 2011年第12期54卷 2519-2527页

作者： wang {1. 1., HU XiaoPing 3 , YAO Li 1.2., XIONG Shi 2.& ZHANG JiaCai 2.1.National Key Laboratory of Cognitive Neuroscience and Learning, {2. normal university, beijing 100875, China 2.College of Information Science and Technology, {2. normal university, beijing 100875, China 3 Biomedical Imaging Technology Center, Emory university/Georgia Institute of Technology, Atlanta 3032., USA National Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing China Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta USA College of Information Science and Technology Beijing Normal University Beijing China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

Supramolecular systems for bioapplications:recent research progress in China

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Science China Chemistry 2024年第5期67卷 1397-1441页

作者： yue-Yang {1. Xiao-Yong yu yu-Chen Pan Hang Yin Shuang Chao yujie Li He Ma Minzan Zuo Kun-Xu Teng Jun-Li Hou Yong Chen Dong-Sheng Guo Ruibing wang yuxin Pei Zhichao Pei {2.-Fei Xu Xiao-yu Hu Chunju Li Qing-Zheng Yang Leyong wang yu {1. Zhan-Ting Li State Key Laboratory of Organometallic Chemistry Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional MoleculesShanghai Institute of Organic ChemistryChinese Academy of SciencesUniversity of Chinese Academy of SciencesShanghai 200032China Department of Chemistry Fudan UniversityShanghai 200438China College of Chemistry State Key Laboratory of Elemento-Organic ChemistryCollaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071China State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacao 999078China College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China Key Lab of Organic Optoelectronics&Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Tianjin Key Laboratory of Structure and Performance for Functional Molecules College of ChemistryTianjin Normal UniversityTianjin 300387China State Key Laboratory of Analytical Chemistry for Life Science Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Supramolecular systems feature dynamic,reversible and stimuli-responsive characteristics,which are not easily achieved by molecular *** last decade has witnessed tremendous advances in the investigations of supramolecular systems for various bioapplications,which include drug delivery,anticancer therapy,antibacterial therapy,photodynamic therapy,photothermal therapy,combination therapy,antidotes for residual drugs or toxins,and bioimaging and ***-guest chemistry has played a key role in the development of such bioactive supramolecular systems,and natural macrocycles(such as cyclodextrins),synthetic macrocycles(such as calixarenes,cucurbit[n]urils,and pillararenes),and porous framework polymers(such as supramolecular organic frameworks and flexible organic frameworks)have been most successfully used as hosts to build different kinds of host-guest systems for attaining designed *** self-assembly of rationally designed amphiphilic molecules,macromolecules and polymers represent another important approach for the construction of supramolecular architectures with advanced *** this review,we summarize the important contributions made by Chinese researchers in this field,with emphasis on those reported in the past five years.

关键词： host-guest chemistry drug delivery anticancer and antibacterial photodynamic therapy photothermal therapy antidote transmembrane channel bioimaging and biosensing

Chlorinated Thiazole-Based Low-Cost Polymer Donors for High Efficiency Binary and Ternary Organic Solar Cells

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CCS Chemistry 2024年第7期6卷 1757-1766页

作者： Hao Lu Hang wang Guang{1. Ran Wenlong {1. Hao Huang Xiaolin jiang Yahui {1. Xinjun Xu Zhishan Bo College of Materials Science and Engineering Qingdao UniversityQingdao 266071 College of Textiles&Clothing State Key Laboratory of Bio-Fibers and Eco-TextilesQingdao UniversityQingdao 266071 beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875 Department of Physics and Applied Optics beijing Area Major Laboratory Beijing Normal UniversityBeijing 100875

In this work,novel D-A alternating polymers(PJ-1.PJ-2.and PJ-3)with chlorinated benzodithiophene and chlorinated thiazole units were synthesized via gradual *** polymers could be obtained readily through a few concise synthesis *** them,PJ-1.displayed desirable properties including energy levels,crystallinity,and charge transport *** binary and ternary organic solar cells(OSCs)fabricated based on PJ-1.displayed significant power conversion efficiency(PCE)of 1..02.and 1..1.0},respectively,placing them among the highest reported for ternary ***,the PJ1.based devices also showcased one of the highest figure-of-merit values,indicating their promising potential for future *** study offers valuable insights and supports the development of costeffective and high-performance polymer donors for the generation of OSCs.

关键词： organic solar cells low-cost donor high efficiency low energy loss ternary blend strategy

Exploring the complex trade-offs and synergies of global ecosystem services

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Environmental Science and Ecotechnology 2024年第5期21卷 141-148页

作者： Jinnan wang Wenjun Wu Meng Yang {1.eming Gao Jiacheng Shao Weishan Yang Guoxia Ma Fang {1. Nan Yao Hongqiang jiang State Environmental Protection Key Laboratory of Environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing100041China The Center for Eco-Environmental Accounting Chinese Academy of Environmental PlanningBeijing100041China The Innovation Center for Eco-environment-Oriented Development Chinese Academy of Environmental PlanningBeijing100041China School of Environment Beijing Normal UniversityBeijing100875China College of Environmental&Resource Sciences Zhejiang UniversityHangzhou310058China College of Economics&Management Northwest A&F UniversityYangling712100China

The trade-off and synergy relationship of ecosystem services is an important topic in the current *** value of each service provided by the ecosystem is substantially affected by human activities,and conversely,its changes will also affect the relevant human *** to varying tradeoffs among ecosystem services and synergies between them that can either increase or decrease,it is difficult to optimize multiple ecosystem services simultaneously,making it a huge challenge for ecosystem *** study firstly develops a global Gross Ecosystem Product(GEP)accounting *** uses remote sensing data with a spatial resolution of 1.km to estimate the ecosystem services of forests,wetlands,grasslands,deserts,and farmlands in 1.9 major countries in *** results show that the range of global GEP values is USD 1.2.1.7 trillion,with an average value of USD 1.5 trillion(the constant price),and the ratio of GEP to gross domestic product(GDP)is *** tradeoffs and the synergies among different ecosystem services in each continent and income group have been further *** found a correspondence between the income levels and the synergy among ecosystem services within each *** specific ecosystem services,there are strong synergies between oxygen release,climate regulation,and carbon sequestration services.A trade-off relationship has been observed between flood regulation and other services,such as water conservation and soil retention services in low-income *** results will help clarify the roles and the feedback mechanisms between different stakeholders and provide a scientific basis for optimizing ecosystem management and implementing ecological compensation schemes to enhance human well-being.

关键词： Ecosystem services Biophysical quantity Monetary value Trade-off Synergy

Phase Change Microcage for Multienergy Capture and Microwave Absorption

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Renewables 2024年第3期2卷 183-193页

作者： Yang Li Zijian Liao Panpan liu {1. jiang Xiao Chen Guanglei Wu Ge {2. School of Physics and Astronomy Beijing Normal UniversityBeijing 100875 Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055 Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071 beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083

Advanced multifunctional composite phase change materials(PCMs)integrating dual-field excitative thermal storage and microwave absorption have been recently highlighted in cutting-edge ***,we designed a metal–organic framework(MOF)derived magnetic NiCo-modified open carbon microcage(NiCo@C)for the encapsulation of PCMs,which simultaneously achieve fast-response multienergy capture and bimode stealth functions:The NiCo@C/PW composite PCMs exhibited a relatively high phase change enthalpy of 1.0.39 J/g due to the high cavity volume of the NiCo@C ***,the composite PCMs demonstrated excellent solar-thermal conversion,attributed to the local surface plasmon resonance effect of NiCo nanoparticles and full-spectrum absorption of high graphitized carbon ***,composite PCMs harvested high-efficiency magnetic-thermal conversion due to the Néel and Brownian relaxation effects of diffusely embedded magnetic NiCo *** importantly,this thermal energy storage system achieved high-performance microwave absorption with a minimum reflection loss(RL)of−38.1.dB at 1..8 GHz at only 2.35 mm *** designed all-in-one strategy created an innovative platform for constructing advanced multifunctional microwave-absorbing composite PCMs with thermal storage,dual-energy conversion,microwave absorption,and infrared stealth.

关键词： phase change materials open microcage multienergy capture thermal energy storage microwave absorption

Probing dark matter particles from evaporating primordial black holes via electron scattering in the CDEX-1. experiment

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 83-91页

作者： Zhenhua Zhang Litao Yang Qian yue Kejun Kang yuanjing Li Haipeng An Greeshma C. Jianping Chang yunhua Chen Jianping Cheng Wenhan Dai Zhi Deng Changhao Fang Xinping Geng Hui Gong Qiuju Guo Tao Guo Xuyuan Guo Li He Shengming He Jinwei Hu Hanxiong Huang Tuchen Huang Lin jiang S.Karmakar Haubin Li Hanyu Li Jianmin Li Jin Li Qianyun Li Renmingjie Li Xueqian Li yulan Li Yifan Liang Bin Liao FongKay Lin ShinTed Lin Jiaxuan liu Shukui liu Yandong liu yu liu yuanyuan liu Hao Ma yucai Mao Qiyuan Nie Jinhua Ning Hui Pan Ningchun Qi Jie Ren Xichao Ruan Monoj Kumar Singh Tianxi Sun Changjian Tang Yang Tian Guangfu wang Junzheng wang Li wang Qing wang yufeng wang yunxiang wang Henry Tsz-King Wong Shiyong Wu yucheng Wu Haoyang Xing Rui Xu Yin Xu Tao Xue yulu Yan Nan Yi Chunxu yu Haijun yu Jianfeng yue Ming Zeng Zhi Zeng Bingtao Zhang Fengshou Zhang Lei Zhang Zhenyu Zhang Jizhong Zhao Kangkang Zhao Minggang Zhao Jifang Zhou Zuying Zhou Jingjun Zhu CDEX Collaboration Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China Institute of Physics Academia SinicaTaipei 11529China NUCTECH Company Beijing 100084China YaLong River Hydropower Development Company Chengdu 610051China College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China College of Physics Sichuan UniversityChengdu 610065China School of Physics Peking UniversityBeijing 100871China Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413China Sino-French Institute of Nuclear and Technology Sun Yet-sen UniversityZhuhai 519082China School of Physics Nankai UniversityTianjin 300071China Department of Physics Banaras Hindu UniversityVaranasi 221005India Department of Physics Beijing Normal UniversityBeijing 100875China 不详

Dark matter(DM)is a major constituent of the ***,no definite evidence of DM particles(denoted as“χ”)has been found in DM direct detection(DD)experiments to *** is a novel concept of detectingχfrom evaporating primordial black holes(PBHs).We search forχemitted from PBHs by investigating their interaction with target *** examined PBH masses range from 1.1.^(1.)to 7×1.^(1.)g under the current limits of PBH abundance *** 2.5.4 kg·day data obtained from the CDEX-1. experiment conducted in the China Jinping Underground Laboratory,we exclude theχ-electron(χ-e)elastic-scattering cross sectionσ_(χe)~5×1.^(-2.)cm^(2.forχwith a mass■keV from our *** the higher radiation background but lower energy threshold(1.0 eV),CDEX-1. fills a part of the gap in the previous ***(m_(χ),σ_(χe))can be determined in the future,DD experiments are expected to impose strong constraints on fPBHfor large MPBHs.

关键词： CDEX primordial black hole light dark matter particle dark matter-electron scattering high purity germanium detector

基于水资源空间均衡的“四水四定”调控模型构建

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水资源保护 2024年第3期40卷 71-77页

作者：魏豪杉王红瑞郏鹏鑫周利超李永坤刘昌明北京师范大学水科学研究院北京100875 中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 临沂市自然资源和规划局山东临沂276001 北京市水科学技术研究院北京100048

为实现未来不同时间尺度下的水资源空间均衡与动态调控,创建了一套完整严谨、可动态调控的“四水四定”模型体系。通过模糊信息粒化窗口的支持向量机模型预测区域未来总用水量,利用基于时间序列相似性分析的自回归支持向量机模型预测区... 详细信息

为实现未来不同时间尺度下的水资源空间均衡与动态调控,创建了一套完整严谨、可动态调控的“四水四定”模型体系。通过模糊信息粒化窗口的支持向量机模型预测区域未来总用水量,利用基于时间序列相似性分析的自回归支持向量机模型预测区域未来分用水量,并对两类数据进行不确定性分析;构建了复杂回归函数对各类用水指标进行情景预测,经统计检验后将其作为当前用水模式下未来用水指标;构建了“四水四定”水资源承载力模型和水资源空间均衡模型,基于未来总用水量、未来各分用水量、未来用水指标,选用水资源负载系数、用水效益和水土资源匹配系数3个指标,结合基尼系数量化水资源空间均衡度,分析当前用水模式下未来水资源均衡度;构建了最优化模型,以最小化基尼系数为目标函数调整未来用水模式,实现水资源动态调控。所创建的模型体系可以实现未来不同时间尺度下的水资源空间均衡与动态调控。

关键词： “四水四定” 水资源空间均衡水资源动态调控时间序列相似性支持向量机模型模糊信息粒化窗口

Using hyperspectral indices to estimate foliar chlorophyll a concentrations of winter wheat under yellow rust stress

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Using hyperspectral indices to estimate foliar chlorophyll a...