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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& liu changming1, {1.1. School of Environmental Sciences, beijing {{1. university, beijing 1.0875, china {1. Institute of Geographic Science and Natural Resources Research, beijing 1.01.1. china School of Environmental Sciences Beijing Normal University Institute of Geographic Science and Natural Resources Research

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82.1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Hua{1.ankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82.to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

Investigation on the vortical structures by the liutex method in turbulent channels at Re_(τ)=1.0 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： Zhang-dan yu Shang {1. Hai-dong yu Bi-yu Pang Xin Dong Yi-qian wang School of Mathematical Sciences Soochow UniversitySuzhou215006China beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)=2. and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and {1.tex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise {1.tex component for the three cases to investigate the energy distribution and characteristics of {1.tex *** {1.tex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

Polyoxometalate as the assembly material to self-assembled Ni(OH)_(2. nanosheets with electrocatalytic performance

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Nano Research 2024年第8期17卷 7061-7067页

作者： Danyang He Tianyang Li Luozhen jiang Fei {1. Zihao Xing Nan {1. Zhiyu Jia Guo-yu Yang Key Laboratory of Cluster Science Ministry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China Shanghai Advanced Research Institute Chinese Academy of ScienceShanghai 201210China Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Facluty of ChemistryNortheast Normal UniversityChangchun 130024China

Developing non-noble metal-based electrocatalyst with high catalytic activity is essential for advancing hydrogen energy *** study introduces a hydrothermal method for synthesizing order Ni(OH)_(2. nanosheets,with H_(3)O_(40)PW_(1.0}(denoted as PW_(1.0})loaded onto reduced graphene oxide(rGO)coated on nickel foam(referred to as PW_(1.0}-Ni(OH)_(2./rGO).This method contrasts with the electrodeposition of Ni(OH)_(2.,where PW_(1.0} is added to the synthetic system to direct the assembly and morphology of the Ni(OH)_(2. through a hydrothermal *** this work,the nickel foam acts dual roles as both the substrate and the source of nickel for the formation of Ni(OH)_(2..The PW_(1.0}-Ni(OH)_(2./rGO nanosheets,when successfully prepared and loaded onto the nickel foam(NF),exhibited superior electrocatalytic activity for the hydrogen evolution reaction(HER)in an alkaline electrolyte,achieving a current density of 1. mA·cm^(-2. at an overpotential of 69 ***,we endeavored to expand the application of this material towards the oxygen evolution reaction(OER)by preparing PW_(1.0}-(Fe/Co)Ni(OH)_(2./rGO through the addition of metal *** nanocomposite displayed outstanding electrocatalytic activity in alkaline electrolytes,with a current density of 1. mA·cm^(-2.at an overpotential of 2.1.mV,and demonstrated excellent stability over a 50 h period in a 1.M KOH *** results presented in this paper offer an effective strategy for the preparation of polyoxometalate-based inorganic materials with diverse functionalities,applicable to both HER and OER.

关键词： polyoxometalate Ni(OH)_(2. assembly hydrogen evolution reaction oxygen evolution reaction

Refining the Factors Affecting N_(2.O Emissions from Upland Soils with and without Nitrogen Fertilizer Application at a Global Scale

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Advances in Atmospheric Sciences 2024年第9期41卷 1804-1820页

作者： Wenqian jiang Siqi LI Yong LI Meihui {1. Bo {1. Ji liu Jianlin SHEN Xunhua ZHENG State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory for Agro-ecological Processes in Subtropical Regions Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125China Changsha Research Station for Agricultural&Environmental Monitoring Chinese Academy of SciencesChangsha 410125China university of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environment SciencesShanghai 200233China Institute of Carbon Neutrality Qilu ZhongkeJinan 251699China Hubei Province Key Laboratory for Geographical Process Analysis and Simulation Central China Normal UniversityWuhan 430079China Department of Ecohydrology Leibniz Institute of Freshwater Ecology and Inland FisheriesBerlin 12587Germany Key laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of EducationNanning Normal UniversityNanning 530001China Golden Mantis school of Architecture Soochow UniversitySuzhou 215123China

Nitrous oxide(N_(2.O)is a long-lived greenhouse gas that mainly originates from agricultural *** and more studies have explored the sources,influencing factors and effective mitigation measures of N_(2.O in recent ***,the hierarchy of factors influencing N_(2.O emissions from agricultural soils at the global scale remains *** this study,we carry out correlation and structural equation modeling analysis on a global N_(2.O emission dataset to explore the hierarchy of influencing factors affecting N_(2.O emissions from the nitrogen(N)and non-N fertilized upland farming systems,in terms of climatic factors,soil properties,and agricultural *** results show that the average N_(2.O emission intensity in the N fertilized soils(1..83 g N ha^(-1.d^(-1.)was significantly greater than that in the non-N fertilized soils(5.34 g N ha^(−1. d^(−1.)(p1..Climate factors and agricultural practices are the most important influencing factors on N_(2.O emission in non-N and N fertilized upland soils,*** different climatic zones,without fertilizer,the primary influence factors on soil N_(2.O emissions are soil physical properties in subtropical monsoon zone,whereas climatic factors are key in the temperate *** fertilizer,the primary influence factors for subtropical monsoon and temperate continental zones are soil physical properties,while agricultural measures are the main factors in the temperate monsoon *** enhanced agricultural practices,such as reduced N fertilizer rate combined with the addition of nitrification and urease inhibitors can potentially mitigate N_(2.O emissions by more than 60%in upland farming systems.

关键词： N_(2.O emissions influencing factors nitrogen cycling upland farming systems

Co/N co-doped flower-like carbon-based phase change materials toward solar energy harvesting

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Aggregate 2024年第1期5卷 321-330页

作者： Xiao Chen Lei wang Yan Gao Yang Li Xiaowei Zhang {1. jiang Ge wang Institute of Advanced Materials Beijing Normal UniversityBeijingChina beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule and Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingChina

The photothermal conversion capacity of pristine organic phase change materials(PCMs)is inherently insufficient in solar energy *** upgrade their photothermal conversion capacity,we developed bimetallic zeolitic imidazolate framework(ZIF)derived Co/N co-doped flower-like carbon(Co/N-FLC)-based composite PCMs toward solar energy harvesting.3D interconnected carbon framework with low interfacial thermal resistance,abundant carbon defects and high content of nitrogen doping,excellent localized surface plasmon resonance(LSPR)effect of Co nanoparticles,and light absorber Co_(3)ZnC in Co/N-FLC synergistically upgrade the photothermal capacity of(polyethylene glycol)PEG@Co/N-FLC composite PCMs with an ultrahigh photothermal conversion efficiency of 94.8%under 0.1. W/cm^(2..Uniformly anchored Co and Co_(3)ZnC nanoparticles in carbon framework guarantee excellent photon capture *** carbon nanotubes(CNTs)in 2. carbon nanosheets further accelerate the rapid transport of phonons by constructing cross-connected heat transfer ***,PEG@Co/N-FLC exhibits a thermal energy storage density of 1.0.69 J/g and excellent thermal stability and durable ***,PEG@Co/N-FLC composite PCMs are promising candidates to accelerate the efficient utilization of solar energy.

关键词： bimetallic ZIF Co/N co-doped carbon phase change materials photothermal conversion thermal energy storage

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, {2. 1.0875, china 3. Water Resources Conservation Committee of Yellow River, Zhengzhou 450003, china Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Science and Natural Resources Research Chinese Academy of Sciences Institute of Environmental Science Beijing Normal University

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.

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

Synthesis of spherical nano-ZSM-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue {1. Jinhong Li Qingxin Xu Shengjie Song yu'ni jiang Lidong Chen Xin Shi Weiguo Cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSM-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSM-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSM-5 is further modified by La_(2.O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSM-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2.O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2.O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSM-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite Modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data

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Chinese Geographical Science 2024年第3期34卷 533-547页

作者： jiang Hongqiang WEI Ye MEI Lin {1. Zhaobo School of Resource and Environment Engineering Ludong UniversityYantai 264025China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Changchun university of Finance and Economics Changchun 130122China Jilin Jizhi City Architectural Design Co. LTDChangchun 130012China

Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination *** paper uses geotagging data to compare the links between attractions in beijing,{1. during four different periods:the pre-Olympic period(2.04–2.07),the Olympic Games and subsequent‘heat period’(2.08–2.1.),the post-Olympic period(2.1.–2.1.),and the COVID-1.(Corona Virus Disease 2.1.)pandemic period(2.2.–2.2.).The aim is to better understand the evolution and patterns of attraction networks at different scales in beijing and to provide insights for tourism planning in the *** results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism *** macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high *** mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of *** pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four diff

关键词： attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning beijing,{1.