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Urban Agglomerations in China: Characteristics and Influencing Factors of Population Agglomeration

Chinese Geographical Science 2023年第4期33卷 719-735页

作者： CAO Yongwang zhang rongrong zhang Dahao ZHOU Chunshan School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China

Urban agglomeration(UA)is an advanced spatial economic form formed and developed in the process of rapid industrialization and urbanization,and an important carrier of urbanization and economic *** economy has developed rapidly in the recent decades of China,and the UAs have also developed ***,as a large population country,the population distribution and changes of UAs in China has unique *** the fifth,sixth and seventh population census data,spatial auto-correlation and spatial econometric models,we analyzed the spatial-temporal evolution characteristics and influencing factors of population agglomeration in China’s *** revealed that:1)from 2000 to 2020,the population gradually converged into UAs,and the characteristics of population agglomeration in different development degree of UAs *** higher the development degree of UA,the higher the population agglomeration ***,UAs are the main area with the most significant population agglomeration degree,and the spatial autocorrelation show that the cities with similar degree tend to be concentrated in *** urban population gathering in UAs has a certain positive spillover effect on population size of neighboring cities.2)Economic development and social conditions factors are important factors affecting population agglomeration degree in *** main factors of population gather into UAs are similar with the outside UAs,but the positive promotion of urbanization rate and proportion of tertiary industry in GDP on population agglomeration of UAs in China are enhancing from 2000 to ***,the other factors,such as high-quality public services,good urban living environment conditions,high-quality medical and educational resources,are also important factors to promote urban population gather into *** study provides a basis for formulating the development planning of UAs in China,and enriches the relevant theoretical research of population evol

关键词： urban agglomerations(UAs) population agglomeration influencing factors spatial econometric models China

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Help from space:grant-free massive access for satellite-based IoT in the 6G era

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Digital Communications and Networks 2022年第2期8卷 215-224页

作者： Neng Ye Jihong Yu Aihua Wang rongrong zhang School of Information and Electronics Beijing Institute of TechnologyBeijing100081China Information Engineering College Capital Normal UniversityBeijing100048China

The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by ***-based communications are recognized as a highly promising technical enabler to satisfy IoT service requirements in the 6G *** study analyzes multiple access technologies,which are essential for the effective deployment of satellite-based ***,we thoroughly investigate the existing research related to massive access,including information-theory considerations as well as Non-Orthogonal Multiple Access(NOMA)and Random Access(RA)***,we explore the influence of the satellite transmission environment on multiple access *** on this study,a Non-orthogonal Massive Grant-Free Access(NoMaGFA)scheme,which reaps the joint benefits of RA and NOMA,is proposed for asynchronous transmissions in satellite-based IoT to achieve improved system throughput and enhance the system robustness under varying ***,we identify some important and interesting future developments for satellite-based IoT,including waveform design,transceiver design,resource allocation,and artificial intelligence-enhanced design.

关键词： Internet of things Satellite communications Non-orthogonal multiple access Random access Asynchronous transmission

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Printability and hardening performance of three-dimensionally-printed geopolymer based on lunar regolith simulant for automated construction of lunar infrastructure

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Frontiers of Structural and Civil Engineering 2023年第10期17卷 1535-1553页

作者： Feng LI rongrong zhang Siqi ZHOU Xingyi ZHU School of Transportation Science and Engineering Beihang UniversityBeijing 100083China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Using an in situ lunar regolith as a construction material in combination with 3D printing not only reduces the weight of materials carried from the Earth but also improves the automation of lunar infrastructure *** study aims to improve the printability of a geopolymer based on a BH-1 lunar regolith simulant,including the extrudability,open time,and buildability,by controlling the temperature and adding *** parameters were used to represent printability with different water-to-binder ratios,printing temperatures,and contents of *** mechanical properties of the hardening geopolymer with different filling paths and loading directions were *** results show that heating the printed filaments with a water-to-binder ratio of 0.32 at 80°C can adjust the printability without adding any additive,which can reduce the construction cost of lunar *** printability of the BH-1 geopolymer can also be improved by adding 0.3%Attagel-50 and 0.5%polypropylene fiber by mass at a temperature of 20℃to cope with the changeable environmental conditions on the *** curing under a simulated lunar environment,the 72-h flexural and compressive strengths of the geopolymer specimens reach 4.1 and 48.1 MPa,respectively,which are promising considering that the acceleration of gravity on the Moon is 1/6 of that on the Earth.

关键词： geopolymer lunar regolith simulant 3D printing rheology printability

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In situ synthesis of FeS/Carbon fibers for the effective removal of Cr(Ⅵ)in aqueous solution

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Frontiers of Environmental Science & Engineering 2020年第4期14卷 147-158页

作者： rongrong zhang Daohao Li Jin Sun Yuqian Cui Yuanyuan Sun School of Environmental Science and Engineering Collaborative Innovation Center for Marine Biomass FiberMaterials and Textiles of Shandong ProvinceQingdao UniversityQingdao 266071China

Iron sulfide(FeS)nanoparticles(termed FSNs)have attracted much attention for the removal of pollutants due to their high efficiency and low cost,and because they are environmentally ***,issues of agglomeration,transformation,and the loss of active components limit their ***,this study investigates in situ synthesized FeS/carbon fibers with an Fecarrageenan biomass as a precursor and nontoxic sulfur source to ascertain the removal efficiency of the *** enrichment of sulfate groups as well as the double-helix structure in i-carrageenan-Fe could effectively avoid the aggregation and loss of FSNs in practical *** obtained FeS/carbon fibers were used to control a Cr(Ⅵ)polluted solution,and exhibited a relatively high removal capacity(81.62 mg/g).T he main mechanisms included the reduction of FeS,electrostatic adsorption of carbon fibers,and Cr(Ⅲ)-Fe(Ⅲ)complexation *** pseudo-second-order kinetic model and Langmuir adsorption model both provided a good fit of the reaction process;hence,the removal process was mainly controlled by chemical adsorption,specifically monolayer adsorption on a uniform ***,co-existing anions,column,and regeneration experiments indicated that the FeS/carbon fibers are a promising remediation material for practical application.

关键词： Carrageenan FeS Double-helix structure Hexavalent chromium

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An enhanced environmental multimedia modeling system based on fuzzy-set approach： I. Theoretical framework and model development

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Frontiers of Environmental Science & Engineering 2015年第3期9卷 494-505页

作者： Chesheng ZHAN rongrong zhang Xiaomeng SONG Baolin LIU Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Department of Building and Transportation Engineering Beijing Urban Construction School Beijing 100026 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China Research Center for Climate Change Ministry of Water Resources Nanjing 210029 China School of Marine Sciences China University of Geosciences Beijing 100083 China

Multimedia environmental modeling is extremely complex due to the intricacy of the systems with the consideration of many related factors. Traditional environmental multimedia models （EMMs） are usually based on one-dimensional and first-order assumptions, which may cause numerical errors in the simulation results. In this study, a new user-friendly fuzzy-set enhanced environmental multimedia modeling system （FEEMMS） is developed, and includes four key modules： an air dispersion module, a polluting source module, an unsaturated zone module, and a groundwater module. Many improvements over previous EMMs have been achieved through dynamically quantifying the intermedia mass flux; incorporating fuzzy-set approach into environmental multimedia modeling system （EMMS）; and designing a user-friendly graphic user interface （GUI）. The developed FEEMMS can be a useful tool in estimating the timevarying and spatial-varying chemical concentrations in air, soil, and groundwater; characterizing the potential risk to human health presented by contaminants released from a contaminated site; and quantifying the uncertainties associated with modeling systems and subsequently providing robustness and flexibility for the remediationrelated decision making.

关键词： environmental multimedia modelling fuzzyset approach theoretical framework environmental protection

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An enhanced environmental multimedia modeling system based on fuzzy-set approach： II. Model validation and application

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Frontiers of Environmental Science & Engineering 2015年第6期9卷 1025-1035页

作者： rongrong zhang Chesheng ZHAN Xiaomeng SONG Baolin LIU Department of Building and Transportation Engineering Beijing Urban Construction School Beijing 100026 China Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 China Research Center for Climate Change Ministry of Water Resources Nanjing 210029 China School of Marine Sciences China University of Geosciences Beijing 100083 China

Part I of this study develops an enhanced environmental multimedia modeling system （EMMS） based on fuzzy-set approach. Once the model development is complete, the composite module and the entire modeling system need to be tested and validated to ensure that the model can simulate natural phenomena with reasonable and reliable accuracy. The developed EMMS is first tested in a complete case study. And then verification results are conducted to compare with extensively researched litera- ture data. In the third step, the data from an experimental landfill site is used for a pilot-scale validation. The comparisons between EMMS outputs and the literature data indicate that the EMMS can perform accurate modeling simulation. The modules of EMMS could support the entire environmental multimedia modeling system. Further field-scale validation is finished. The results are satisfactory. Most of the modeling yields closely match the monitoring data collected from sites. In addition, with the aid of fuzzy-set approach, EMMS can be a reliable and powerful tool to address the complex environmental multimedia pollution problems and provide an extensive support for decision makers in managing the contaminated environmental systems.

关键词： environmental multimedia modelling system fuzzy-set approach application model validation uncer-tainty analysis

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Microwave-promoted Synthesis of Novel Fused Osthole Analogues

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Chinese Journal of Chemistry 2016年第12期34卷 1344-1352页

作者： Mingzhi zhang rongrong zhang Jiaqun Wang Xiang Yu Yaling zhang Qingqing Wang Weihua zhang Jiangsu Key Laboratory of Pesticide Science College of Sciences Nanjing Agricultural University Nanjing Jiangsu 210095 China

Osthole is a natural coumarin derivative and has a broad scope of biological activities. Two series of novel fused osthole analogues were designed, and synthesized through a highly efficient microwave-promoted synthetic proto- col via the reaction of 4-hydroxycoumarins and fl-ketoesters. The reaction conditions including solvent, catalyst, microwave power and irradiation time were also optimized. The pyrano[3,2-c]chromene-2,5-diones and furo[3,2-c]- coumarins were obtained through two distinct intramolecular cyclization processes, and the proposed mechanism was also discussed.

关键词： osthole microwave-promoted synthesis pyrano[3,2-c]chromene-2,5-diones furo[3,4-c]coumarins mechanism

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Metal-oxoacid-mediated oxyhydroxide with proton acceptor to break adsorption energy scaling relation for efficient oxygen evolution

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Journal of Energy Chemistry 2023年第5期80卷 594-602,I0013页

作者： rongrong zhang Beibei Guo Lun Pan Zhen-Feng Huang Chengxiang Shi Xiangwen zhang Ji-Jun Zou Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207FujianChina Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Metal oxyhydroxides(MOOH)generated from irreversible reconstructions of transition metal compounds are intrinsic active species for oxygen evolution reaction,whose activities are still constrained by sluggish deprotonation kinetics and inherent adsorption energy scaling ***,we construct a tunable proton acceptor(TPA)on oxyhydroxides by in-situ reconstruction of metal oxoacids such as NiC2O4to accelerate deprotonation and break adsorption energy scaling relations during *** modified C_(2)O_(4)^(2-)as a TPA can easily extract H of*OH(forming*HC2O4intermediate)and then promote deprotonation by the transmitted hydrogen bond with*OOH along conjugated(H...)O=C-O(-H)*** a result,Ni OOH-C2O4shows non-concerted proton-electron transfer and improved deprotonation rate,and delivers a good OER activity(270 mV@10 mA cm-2).The conjugate acidity coefficient(pKa)of the modified oxoacid group can be a descriptor for TPA *** TPA strategy can be universally applied to Co-,Fe-,and Ni-based oxyhydroxides to facilitate OER efficiency.

关键词： Electrocatalysis Metal oxyhydroxide Oxoacid group Tunable proton acceptor Oxygen evolution reaction

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Dc GA20ox2 and DcGA2ox1 alter endogenous gibberellin contents and adjust lignin accumulation in carrot

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Horticultural Plant Journal 2024年第6期10卷 1398-1413页

作者： Min Jia Yahui Wang Chen Chen rongrong zhang Guanglong Wang Aisheng Xiong State Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization Ministry of Agriculture and Rural Affairs Key Laboratory of Biology and Germplasm Enhancement of Horticultural Crops in East ChinaCollege of HorticultureNanjing Agricultural UniversityNanjingJiangsu 210095China School of Life Science and Food Engineering Huaiyin Institute of TechnologyHuaianJiangsu 223003China

Gibberellins(GAs)are a class of plant hormones that can affect plant growth and ***-oxidases are rate-limiting enzymes,which play a direct role in GA accumulation in ***,the roles of GA-oxidase on carrot(Daucus carota L.)taproot development are still *** this study,two GA-oxidase genes,DcGA20ox2 and DcGA2ox1,were identified in *** carrot plants were obtained by using Agrobacterium-mediated genetic transformation *** results showed that overexpression of DcGA20ox2 significantly promoted the accumulation of active GAs in carrot,increased plant height,generated more branches,and enhanced xylem *** of DcGA2ox1 significantly reduced the total contents of active GAs compared with the control group,resulting in a dwarf phenotype and markedly increased lignin content of the transgenic *** expression profiling showed that the genes of GA metabolic pathway responded to the negative feedback regulation *** the same time,the expression of most genes in lignin biosynthesis and polymerization process was up-regulated,corresponding to the massive accumulation of *** findings indicated that DcGA20ox2 and DcGA2ox1affected carrot growth and development by regulating the levels of endogenous *** results from current work might shed light on further studies aimed to regulate lignification in carrot and other crops.

关键词： Daucus carota Gibberellin GA-oxidase Lignin GA accumulation

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Genome-wide evolution of MAPKs family and their expression in response to bacterial infection in seahorse Hippocampus erectus

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Journal of Oceanology and Limnology 2021年第6期39卷 2309-2321页

作者： Kai WANG Xin WANG Qiang ZOU Han JIANG rongrong zhang Yanan TIAN Lele zhang Qiang LIN School of Agriculture Ludong UniversityYantai 264025China CAS Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Yantai Branch of Shandong Technology Transfer Center Chinese Academy of SciencesYantai 264003China University of Chinese Academy of Sciences Beijing 100049China

Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic *** mitogenactivated protein kinases(MAPKs)are known to be involved in various important biological processes including growth,differentiation,immunity,and stress ***,we hypothesized that the adaptive evolution and expression of the MAPK gene family in seahorse may differ from those of other teleost *** identified positive selection sites in the erk2,erk5,jnk1,and p38αMAPK genes of the lined seahorse Hippocampus erectus and tiger-tailed seahorse Hippocampus comes.A novel expression profile of MAPK cascade genes was found in seahorse larvae during the first day after birth based on the RNA-seq data of ***,which refl ected vital signs of immune response to its parental immune *** expression patterns of the four positively selected MAPK genes were analyzed following the bacterial challenge of Vibrio fortis,revealing their upregulation pattern in brood pouch and other immune *** study enriched our knowledge of the evolution of the *** MAPK subfamilies,and could help better understanding the functional role of MAPKs in teleosts.

关键词： mitogen-activated protein kinases(MAPKs) Hippocampus erectus genomic structure positive selection immune regulation

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