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In-situ Urbanization Promoted by the Development of "Taobao Village"
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作者 Shengbo Zhang 《International Journal of Technology Management》 2015年第12期67-70,共4页
Starting from the important role of "Taobao village" in the economic development, the thesis analysed the subjective and objective reasons and promoting group and draw the general process of urbanization. It discuss... Starting from the important role of "Taobao village" in the economic development, the thesis analysed the subjective and objective reasons and promoting group and draw the general process of urbanization. It discussed the different characteristics of "Taobao village" in different economic areas and roles played in urbanizing. It also propounded some constructive suggestion to activate the industry, including strengthening industry supervision, adjusting development patterns, and emphasizing innovation. The paper consists of literature analysis, case analysis and comparative analysis to complement the demonstration. 展开更多
关键词 electronic commerce COUNTRY in-situ urbanization Taobao village
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Spatio-temporal Evolution Characteristics and Driving Forces of Winter Urban Heat Island:A Case Study of Rapid Urbanization Area of Fuzhou City,China 被引量:1
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作者 WANG Zili LU Chunyan +4 位作者 SU Yanlin SU Yue YU Qianru LI Wenzhe YANG Nuocheng 《Chinese Geographical Science》 SCIE CSCD 2024年第1期135-148,共14页
Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human... Under the influence of anthropogenic and climate change,the problems caused by urban heat island(UHI)has become increasingly prominent.In order to promote urban sustainable development and improve the quality of human settlements,it is significant for exploring the evolution characteristics of urban thermal environment and analyzing its driving forces.Taking the Landsat series images as the basic data sources,the winter land surface temperature(LST)of the rapid urbanization area of Fuzhou City in China was quantitatively retrieved from 2001 to 2021.Combing comprehensively the standard deviation ellipse model,profile analysis and GeoDetector model,the spatio-temporal evolution characteristics and influencing factors of the winter urban thermal environment were systematically analyzed.The results showed that the winter LST presented an increasing trend in the study area during 2001–2021,and the winter LST of the central urban regions was significantly higher than the suburbs.There was a strong UHI effect from 2001 to 2021with an expansion trend from the central urban regions to the suburbs and coastal areas in space scale.The LST of green lands and wetlands are significantly lower than croplands,artificial surface and unvegetated lands.Vegetation and water bodies had a significant mitigation effect on UHI,especially in the micro-scale.The winter UHI had been jointly driven by the underlying surface and socio-economic factors in a nonlinear or two-factor interactive enhancement mode,and socio-economic factors had played a leading role.This research could provide data support and decision-making references for rationally planning urban layout and promoting sustainable urban development. 展开更多
关键词 winter urban heat island(UHI) rapid urbanization area land surface temperature(LST)retrieval profile analysis GeoDetector model Fuzhou City China
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Optimal depth of in-situ pressure-preserved coring in coal seams considering roadway excavation and drilling disturbance
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作者 Peng-Fei Cui De-Lei Shang +5 位作者 Peng Chu Ju Li Da-Li Sun Tian-Yu Wang Ming-Zhong Gao He-Ping Xie 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3517-3534,共18页
Using pressure-preserved coring technique to determine in-situ gas content provides a more precise assessment of gas resource reserves and safeguard of mining safety in coal seams. How coring technique and depth affec... Using pressure-preserved coring technique to determine in-situ gas content provides a more precise assessment of gas resource reserves and safeguard of mining safety in coal seams. How coring technique and depth affect the determination of gas content is unclear due to borehole zoning rupture caused by roadway excavation and drilling disturbance. To this end, a proposed coupling model of stress distribution and gas migration was simulated and validated by FLAC^(3D) and COMSOL Multiphysics considering superposition effects of roadway excavation and drilling disturbance. The findings indicate that the roadway surrounding rock displays distinct zoning features including stress relief zone, stress concentration zone that is composed of plastic zone, elastic zone, and original stress zone;and the broken situations depending on the borehole peeping are consistent with the corresponding simulation results.On this basis, this study proposes a set of drilling coring depth calculation and prediction model for the gas desorption affected area under engineering disturbance. Optimal depth of coring drilling is not only approach to the in-situ coal bulk, but also can get the balance of the drilling workload and cost controlling. According to the typical mine site geological conditions and the numerical simulation results in this study, if the roadway excavation time is ~1 year, it is recommended that the pressure-preserved coring depth should be greater than 17 m. 展开更多
关键词 in-situ fidelity coring in-situ pressure preserved coring Gas content Drilling disturbance Coring depth Excavation damage zone
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Effects of urbanization and forest type on species composition and diversity,forest characteristics,biomass carbon sink,and their associations in Changchun,Northeast China:implications for urban carbon stock improvement
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作者 Yuanyuan Wang Xinzhu Dai +5 位作者 Xingling Chen Dan Zhang Guiqing Lin Yuanhang Zhou Tianyi Wang Yulong Cui 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期146-162,共17页
Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban... Differences in forest attributes and carbon sequestration of each organ and layer between broadleaved and conifer forests of central and outer urban areas are not well-defined,hindering the precise management of urban forests and improvement of function.To clarify the effect of two forest types with different urbanization intensities,we determined differences in vegetation composition and diversity,structural traits,and carbon stocks of 152 plots(20 m×20 m)in urban park forests in Changchun,which had the largest green quantity and carbon density effectiveness.We found that 1.1-fold thicker and healthier trees,and 1.6-to 2.0-fold higher,healthier,denser,and more various shrubs but with sparser trees and herbs occurred in the central urban forests(p<0.05)than in the outer forests.The conifer forests exhibited 30–70%obviously higher tree aboveground carbon sequestration(including stem and leaf)and 20%bigger trees,especially in the outer forests(p<0.05).In contrast,1.1-to 1.5-fold higher branch stocks,healthier and more diverse trees were found in broadleaved forests of both the inner and outer forests(p<0.05).Plant size and dominant species had similarly important roles in carbon stock improvement,especially big-sized woody plants and Pinus tabuliformis.In addition,a higher number of deciduous or needle species positively affected the broadleaved forest of the central urban area and conifer forest of the outer urban area,respectively.These findings can be used to guide precise management and accelerate the improvement of urban carbon function in Northeast China in the future. 展开更多
关键词 Species diversity Forest characteristics Biomass carbon sink Forest-type effect urbanization effect urban forests
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Long-term dynamics and driving factors of phytoplankton biomass during urbanization, northern China
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作者 Kangxu ZHAO Junping LÜ +5 位作者 Fangru NAN Xudong LIU Hui LING Congjie PANG Shulian XIE Jia FENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第6期1928-1942,共15页
Understanding the relative impact of nutrients and related environmental variables on phytoplankton biomass changes in urban rivers is important for river management.In this study,we explored the long-term dynamic cha... Understanding the relative impact of nutrients and related environmental variables on phytoplankton biomass changes in urban rivers is important for river management.In this study,we explored the long-term dynamic changes and driving factors of phytoplankton biomass in the process of urbanization from the perspective of time and space,and provided a scientific support to water ecological health assessment and management of urban rivers.From 2012 to 2021,the phytoplankton community composition in Taiyuan section of Fenhe River was found to be dominated by Cyanophyta,Chlorophyta,and Bacillariophyta.Among them,cyanobacteria were the main contributors to the total abundance,green algae ranked second,and diatoms were the least.The biomass of phytoplankton in different groups showed different decreasing trends.Based on 10 environmental factors to explain the changes of three main phytoplankton groups(cyanobacteria,green algae,diatoms),we found that chemical oxygen demand and water temperature had a high explanation rate for the abundance changes of the three main phytoplankton groups,which were important environmental factors affecting their biomass changes.The random forest model was used to analyze the changes in the total biomass of phytoplankton.It was found that the permanganate index had a higher contribution to the total biomass of phytoplankton in time.The contribution of air temperature to the total biomass of phytoplankton was higher in space. 展开更多
关键词 phytoplankton biomass environmental factor urbanization
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New Patterns of County In-Situ Urbanization and Rural Development: Perspective of E-Commerce 被引量:1
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作者 Xu Chan LüBin +1 位作者 Wen Tianzuo Qian Fang(译) 《China City Planning Review》 CSCD 2017年第4期34-41,共8页
Starting with the connotation of e-commerce and its development in counties,this paper analyzes the impact of e-commerce upon the urbanization pattern in China,and argues that influenced by the growing popularity of e... Starting with the connotation of e-commerce and its development in counties,this paper analyzes the impact of e-commerce upon the urbanization pattern in China,and argues that influenced by the growing popularity of e-commerce in the internet era,human resources and economies at all city levels will get increasingly equal access to opportunities,and the centrality of big cities is compromised.In addition,counties and villages within their jurisdiction are presented with unprecedented opportunities.Development in rural areas will achieve a radical transition from being industrialization-driven to information-driven.This paper further sheds light on the fact that under this new urbanization trend,county in-situ urbanization and rural development driven by e-commerce will be a new approach toward urbanization in China.Then,in-depth analysis into the connotation and approaches of county in-situ urbanization is given,alongside with three different patterns for rural development which are the extension pattern,intervention pattern,and endogenesis pattern respectively,providing implication for the new urbanization in the context of information age of China. 展开更多
关键词 E-COMMERCE COUNTY urbanization rural area
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Examining the Spatiotemporal Dynamics and Determinants of Land Urbanization in Prefecture-level Cities,China
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作者 YANG Zhen ZHU Huxiao +1 位作者 ZHANG Xinlin OU Xiangjun 《Chinese Geographical Science》 SCIE CSCD 2024年第1期19-33,共15页
Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change... Examining the spatiotemporal dynamics and determinants of land urbanization is critical for promoting healthy urban development and the rational use of land resources.Based on the dataset consisting of land use change data and selected factors in 2010 and2020,this study used visual analysis to reveal the spatiotemporal dynamics of land urbanization across prefecture-level cities in China.Meanwhile,the driving forces underlying land urbanization were examined by using geographical detector technique.Following are the findings:1)we find that there exist notable spatial variances in land urbanization across prefecture-level cities.Currently,the differentiation in land urbanization between the northern and southern cities is more pronounced than that between the coastal and inland cities,or between the eastern and western cities.Prefecture-level cities located in central and western China have experienced the most rapid growth in land urbanization.Conversely,the growth rate in northeastern China is the lowest,while the velocity in eastern China remains relatively stable.By using spatial autocorrelation analysis,this study reveals that the land urbanization level in prefecture-level cities has significant spatial agglomeration.2)We further find that land urbanization in China is influenced by factors related to urban land supply and demand,and urban population growth,economic growth,land financial and political incentive have greater impact on land urbanization than other factors.3)We also find that the impacts of determinants on China’s land urbanization vary over time,the explanatory power of economic development increased,while the explanatory power of state forces declined.We argue that integrating the supply and demand factors of land urbanization can provide a more comprehensive understanding of the driving mechanisms underlying land urbanization in China and other transitional countries,and help decision-makers in these countries formulate more detailed and specific land urbanization policies. 展开更多
关键词 land urbanization spatial pattern influencing factor geographical detector China
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Evolutionary characteristics and influencing factors of agricultural regional system in the Loess Plateau of China under rapid urbanization
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作者 LI Shunke LIU Yansui +2 位作者 LI Yuheng SHAO Yajing WANG Xiaochen 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3650-3668,共19页
The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanizatio... The rapid expansion of cities seriously threatens the sustainable development of agriculture in China.Exploring the evolution law and influencing mechanism of agricultural regional system in the process of urbanization is of great significance for promoting sustainable development of agriculture in China.This paper takes the Loess Plateau(LP)as an example,and constructs a research framework to study the effect of urbanization on agricultural regional system through the lens of human-earth interaction,aiming at elucidating the evolutionary characteristics of agricultural regional system and revealing the impact law of urbanization.The results show that:(1)The growth trend of the evolution index of the agricultural regional system in the LP was significant,gradually evolving into a spatial pattern of"high in the north and south,low in the east and west".(2)The hot spot and sub-hot spot zones of the agricultural regional system evolution index in the LP were mainly distributed in the south and north,while the cold spot and sub-cold spot zones were primarily located in the center,east and west.(3)The levels of agricultural mechanization,agricultural land productivity,cropland area,and agricultural labor productivity were the main internal influencing factors of the agricultural regional system in the LP.The obstacle degree of agricultural mechanization level,cropland area,and the proportion of agricultural employees increased over time,while the obstacle degree of agricultural land productivity and grain yield capacity decreased.(4)The impact of population urbanization in the LP showed a spatial pattern of"inhibition in the southeast and promotion in the northwest",the impact of economic urbanization was dominated by inhibition,and the impact of land urbanization showed a spatial pattern of"promotion in the whole and inhibition in the local".This study provides ideas for the comprehensive research on the evolution and influencing factors of agricultural regional system,and offers practical references for achieving sustainable agricultural development in LP. 展开更多
关键词 Agricultural regional system Loess Plateau urbanization Geographically and temporally weighted regression
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Anthropogenic nesting materials and reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China
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作者 Xingmin Chen Qin Zhang +3 位作者 Sisi Lan Qin Huang Shuihua Chen Yanping Wang 《Avian Research》 SCIE CSCD 2024年第4期431-437,共7页
Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wil... Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wildlife.Interestingly,an emerging trend has been observed that birds are incorporating anthropogenic materials into their nests.However,the relationship between anthropogenic nesting materials(ANMs)and the reproductive performance of urban birds is unclear.In this study,we investigated the relationship between the incorporation of ANMs into nests and the reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)by monitoring and collecting data on 136 breeding nests in Hangzhou,China.We gathered data on seven reproductive traits of Chinese Bulbuls,including laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate.We then calculated the urbanization synthetic index as a measure of the level of urbanization and examined its relationship with the proportion and weight of ANMs.Through examination of nest components,we observed significant increase in the proportion and weight of ANMs with the urbanization synthetic index.Notably,we found a higher hatching success rate of Chinese Bulbuls with an increasing proportion of ANMs.However,the inclusion of ANMs in nests was not correlated with other reproductive traits of Chinese Bulbuls.Overall,the use of ANMs by Chinese Bulbuls is consistent with the adaptive hypothesis and the availability hypothesis.Further studies should use controlled experiments to investigate the impact of ANMs on avian reproductive success. 展开更多
关键词 Adaptive hypothesis Anthropogenic nesting materials Availability hypothesis Hatching success Reproductive traits urbanization
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Impact of air pollution on urbanization:evidence at China’s city level
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作者 Yanchun Yi Yixin Geng +1 位作者 Jiawen Wu Yinling Liu 《Chinese Journal of Population,Resources and Environment》 2024年第3期268-274,共7页
This paper investigates the effect and transmission mechanism of air pollution on urbanization based on data from China’s 107 cities during 2005–2018.In order to identify the impact of air pollution on China’s urba... This paper investigates the effect and transmission mechanism of air pollution on urbanization based on data from China’s 107 cities during 2005–2018.In order to identify the impact of air pollution on China’s urbanization,we utilized night light data to represent the level of urbanization and used temperature inversion as an instrumental variable to mitigate endogeneity within the two-stage least squares framework.The results suggest that air pollution significantly slowed China’s urbanization process with economic growth acting as the transmission mechanism.The heterogeneity analyses revealed that air pollution had a greater negative impact on urbanization in northern regions than that in southern regions,and a greater negative impact in resource-oriented cities than that in non-resource-based cities.We also find that air pollution was to the detriment of urbanization in larger cities,which have more than 3 million residents,while it did not have a significant impact on Type II large cities,which have fewer than 3 million residents. 展开更多
关键词 Air pollution urbanization Influencing mechanism 2SLS Night light data Instrumental variable
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Research on the Digital Economy's Impact on China's Economic Growth:Based on the Variations in Urbanization Levels Across China's Eastern,Central,and Western Regions and Sectoral Heterogeneity
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作者 Qiu Jin Yan Hong 《Contemporary Social Sciences》 2024年第3期27-44,共18页
This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth a... This paper uses inter-provincial panel data from 2011 to 2017,a linear regression model,and a threshold model to conduct empirical analyses of the impact of the digital economy on China's overall economic growth and the three main sectors of industry.The paper then investigates the impact and effects the digital economy has had on the economic growth of the three main sectors of industry in China's eastern,central,and western regions.Finally,the paper investigates the most significant differences among the various regions and the threshold effects of urbanization levels on the relationship between the digital economy and economic growth.The findings indicate a significantly positive correlation between the digital economy and regional economic growth.Moreover,geographical factors notably influence this correlation.The digital economy exerts a positive effect on all sectors of industry.It may not substantially impact industrial development in regions with highly developed infrastructure.Regarding the other regions,the digital economy exhibits varying degrees of impact due to the differences in the specific indicators.The conclusion drawn by the threshold model is that the magnitude of the threshold effect correlates with geographic factors.No threshold effect was observed in the eastern region,while the threshold effect occurred in the central region when the urbanization levels for the provinces were below 0.6645.Similarly,the threshold effect was noted in the western region when the urbanization level was below 0.3931.Considering all of this,the study also offers policy recommendations that will help balance the regional development of digital economies,accelerate the digital transformation of traditional industries,enhance digital infrastructure construction,refine the formulation and implementation of data policy,and establish relevant incentive mechanisms. 展开更多
关键词 digital economy economic growth regional differences urbanization level threshold models
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The Implications of Urbanization Processes in Developed Countries for Africa
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作者 YANG Li LI Kaili 《International Relations and Diplomacy》 2024年第2期51-58,共8页
Urbanization is the inevitable path of national economic development,and the level of urbanization development in most African countries is still low.By analyzing five typical developed countries in the United States,... Urbanization is the inevitable path of national economic development,and the level of urbanization development in most African countries is still low.By analyzing five typical developed countries in the United States,Britain,France,Germany,and Japan,this paper discusses the promoting factors and problems of the rapid urbanization development in their specific years,as well as the experiences and lessons that Africa can learn,so as to prevent Africa from taking the detour in the urbanization process of Western developed countries and promote the balanced regional development of various African countries. 展开更多
关键词 developed countries AFRICA urbanization
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Local Climate Change Induced by Urbanization on a South China Sea Island
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作者 郝宇 李磊 +2 位作者 陈柏纬 孙伟 戴永久 《Journal of Tropical Meteorology》 SCIE 2024年第1期11-19,共9页
The South China Sea is a hotspot for regional climate research.Over the past 40 years,considerable improvement has been made in the development and utilization of the islands in the South China Sea,leading to a substa... The South China Sea is a hotspot for regional climate research.Over the past 40 years,considerable improvement has been made in the development and utilization of the islands in the South China Sea,leading to a substantial change in the land-use of the islands.However,research on the impact of human development on the local climate of these islands is lacking.This study analyzed the characteristics of local climate changes on the islands in the South China Sea based on data from the Yongxing Island Observation Station and ERA5 re-analysis.Furthermore,the influence of urbanization on the local climate of the South China Sea islands was explored in this study.The findings revealed that the 10-year average temperature in Yongxing Island increased by approximately 1.11℃from 1961 to 2020,and the contribution of island development and urbanization to the local warming rate over 60 years was approximately 36.2%.The linear increasing trend of the annual hot days from 1961–2020 was approximately 14.84 days per decade.The diurnal temperature range exhibited an increasing trend of 0.05℃per decade,whereas the number of cold days decreased by 1.06days per decade.The rapid increase in construction on Yongxing Island from 2005 to 2021 led to a decrease in observed surface wind speed by 0.32 m s^(-1)per decade.Consequently,the number of days with strong winds decreased,whereas the number of days with weak winds increased.Additionally,relative humidity exhibited a rapid decline from 2001 to 2016 and then rebounded.The study also found substantial differences between the ERA5 re-analysis and observation data,particularly in wind speed and relative humidity,indicating that the use of re-analysis data for climate resource assessment and climate change evaluation on island areas may not be feasible. 展开更多
关键词 local climate climate change Yongxing Island a South China Sea island climate change induced by urbanization
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Recent urbanization increases exposure to humid-heat extreme events over populated regions of China 被引量:1
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作者 Huopo Chen Wenyue He Shuhui Zhang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第2期7-12,共6页
目前对于高温的研究主要侧重于干热,针对湿热的研究相对较少,但它通常会造成更大的社会影响,尤其对人体健康的威胁.已有研究证实,当环境湿球温度超过35℃时,它会破坏人体正常生理代谢,进而威胁人体健康.本研究指出在过去四十年,中国区... 目前对于高温的研究主要侧重于干热,针对湿热的研究相对较少,但它通常会造成更大的社会影响,尤其对人体健康的威胁.已有研究证实,当环境湿球温度超过35℃时,它会破坏人体正常生理代谢,进而威胁人体健康.本研究指出在过去四十年,中国区域日最高湿球温度几乎没有超过35℃,但部分地区日最高湿球温度超过了30℃,主要集中在中国的人口密集区,包括华东,华南和四川盆地等.进一步分析发现,中国区域近期的快速城市化加剧了极端湿热事件的社会影响,城市地区暴露于极端湿热事件的范围的增加速率明显大于其他地区,这也意味着快速城市化使得人口密集区暴露于极端湿热事件的风险明显增加.初步估算指出,自2000年以来,中国区域暴露于极端湿热事件的人口数以每年每天约3100人次的速率显著增加. 展开更多
关键词 极端湿热 湿球温度 城市化 暴露
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Overview of in-situ oxygen production technologies for lunar resources
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作者 Youpeng Xu Sheng Pang +5 位作者 Liangwei Cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期233-255,共23页
The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extract... The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial resources.Oxygen,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic oxides.This oxygen and metal extraction can be achieved using existing metallurgical techniques.Furthermore,the ample reserves of water ice on the Moon offer another means for oxygen production.This paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental conditions.It delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar regolith.The two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the Moon.Considering the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the Moon.This review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives. 展开更多
关键词 lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis
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From earthquake resistance structure to earthquake resilience city–urban seismic resilience assessment
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作者 Xie Lili Zhao Yonggang +1 位作者 Wen Weiping Zhai Changhai 《Earthquake Engineering and Engineering Vibration》 2025年第1期1-13,共13页
Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept o... Earthquakes pose significant perils to the built environment in urban areas.To avert the calamitous aftermath of earthquakes,it is imperative to construct seismic resilient cities.Due to the intricacy of the concept of urban seismic resilience(USR),its assessment is a large-scale system engineering issue.The assessment of USR should be based on the notion of urban seismic capacity(USC)assessment,which includes casualties,economic loss,and recovery time as criteria.Functionality loss is also included in the assessment of USR in addition to these criteria.The assessment indicator system comprising five dimensions(building and lifeline infrastructure,environment,society,economy,and institution)and 20 indicators has been devised to quantify USR.The analytical hierarchy process(AHP)is utilized to compute the weights of the criteria,dimensions,and indicators in the urban seismic resilience assessment(USRA)indicator system.When the necessary data for a city are obtainable,the seismic resilience of that city can be assessed using this framework.To illustrate the proposed methodology,a moderate-sized city in China was selected as a case study.The assessment results indicate a high level of USR,suggesting that the city possesses strong capabilities to withstand and recover from potential future earthquakes. 展开更多
关键词 urban seismic capacity urban seismic resilience assessment analytic hierarchy process functionality loss
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Multiphysics simulation and optimization of the in-situ beneficiation process of ilmenite minerals from lunar regolith
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作者 Peng ZHANG Xin LIU +11 位作者 Guanghui LIU Wei DAI Hanzhe YANG Haibo ZHENG Zhi WANG Ran NIU Yifan BAI Yang ZHANG Chengbao LIU Ge YANG Junwei YANG Guang ZHANG 《Science China Earth Sciences》 2025年第1期195-207,共13页
The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions.The classified collection and processing of lunar minerals is the basic prerequisite for the in-... The exploration and utilization of lunar resources have become the major objectives of future lunar exploration missions.The classified collection and processing of lunar minerals is the basic prerequisite for the in-situ exploration and utilization of lunar resources.In this study,we propose a scheme for in-situ separation of magnetic minerals from lunar soils using the dry magnetic separation method.The scheme can realize the purpose of separating magnetic minerals from lunar regolith by altering the motion trajectory of lunar regolith particles with different magnetic properties.Detailed modeling of the dry magnetic separation device is conducted,and the three-dimensional distribution of magnetic parameters is calculated and analyzed.Based on the characterization and analysis of the Chang E-5's samples,the morphologies and physical parameters of lunar regolith particles are modeled and simulated.A discrete element simulation of the motion process of lunar regolith particles under multi-physical field conditions is performed,and the influences of key parameters on the beneficiation performance of lunar magnetic minerals are investigated.Our results indicate that optimal separation and beneficiation of lunar regolith particles can be achieved under specific conditions of magnetic field strength and drum speed.Additionally,we analyze the effects of lunar weak gravity conditions and the charged nature of lunar particles on the beneficiation process,showing that these factors can obviously enhance the beneficiation process of lunar ilmenites.This study demonstrates the feasibility of using the dry magnetic separation method for the beneficiation of magnetic minerals from lunar regolith,providing a theoretical basis for the scientific tasks of collecting,processing,and utilizing lunar mineral resources. 展开更多
关键词 Lunar regolith in-situ resource utilization Magnetic separation Classified sampling
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Spatiotemporal variation and driving factors of vegetation net primary productivity in the Guan-zhong Plain Urban Agglomeration,China from 2001 to 2020
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作者 LIU Yuke HUANG Chenlu +1 位作者 YANG Chun CHEN Chen 《Journal of Arid Land》 2025年第1期74-92,共19页
Studying the spatiotemporal variation and driving mechanisms of vegetation net primary productivity(NPP)in the Guanzhong Plain Urban Agglomeration(GPUA)of China is highly important for regional green and low-carbon de... Studying the spatiotemporal variation and driving mechanisms of vegetation net primary productivity(NPP)in the Guanzhong Plain Urban Agglomeration(GPUA)of China is highly important for regional green and low-carbon development.This study used the Theil-Sen trend analysis,Mann-Kendall trend test,coefficient of variation,Hurst index,and machine learning method(eXtreme Gradient Boosting and SHapley Additive exPlanations(XGBoost-SHAP))to analyze the spatiotemporal variation of NPP in the GPUA from 2001 to 2020 and reveal its response to climate change and human activities.The results found that during 2001-2020,the averageNPP in the GPUA showed a significant upward trend,with an annual growth rate of 10.84 g C/(m^(2)•a).The multi-year average NPP in the GPUA was 484.83 g C/(m^(2)•a),with higher values in the southwestern Qinling Mountains and lower values in the central and northeastern cropland and built-up areas.The average coefficient of variation of NPP in the GPUA was 0.14,indicating a relatively stable state overall,but 72.72%of the study area showed weak anti-persistence,suggesting that NPP in most areas may have declined in the short term.According to XGBoost-SHAP analyses,elevation,land use type and precipitation were identified as the main driving factors of NPP.Appropriate precipitation and higher temperatures promote NPP growth,whereas extreme climates,high population density,and nighttime lighting inhibit NPP.This study has important theoretical and practical significance for achieving regional sustainable development,offers a scientific basis for formulating effective ecological protection and restoration strategies,and promotes green,coordinated,and sustainable development in the GPUA. 展开更多
关键词 net primary productivity(NPP) Theil-Sen trend analysis machine learning climate change urbanization Guanzhong Plain urban Agglomeration(GPUA)
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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses
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作者 Bin Sun Yi Liu +4 位作者 Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 《Acta Geochimica》 2025年第1期112-127,共16页
The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambigu... The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibit a narrow range(19-31),with a pronounced correlation between the contents of Y and Ho and a similar trend in their variation.This consistency suggests that the Guanfang deposit has undergone a uniform or comparable evolutionary process,implying a stable ore-forming fluid across diff erent mineralization stages. 展开更多
关键词 Guanfang W deposit Trace elements of scheelite in-situ Sr isotopes Southeast Yunnan
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Dynamic partition of urban network considering congestion evolution based on random walk
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作者 Zhen-Tong Feng Lele Zhang +1 位作者 Yong-Hong Wu Mao-Bin Hu 《Chinese Physics B》 2025年第1期530-534,共5页
The successful application of perimeter control of urban traffic system strongly depends on the macroscopic fundamental diagram of the targeted region.Despite intensive studies on the partitioning of urban road networ... The successful application of perimeter control of urban traffic system strongly depends on the macroscopic fundamental diagram of the targeted region.Despite intensive studies on the partitioning of urban road networks,the dynamic partitioning of urban regions reflecting the propagation of congestion remains an open question.This paper proposes to partition the network into homogeneous sub-regions based on random walk algorithm.Starting from selected random walkers,the road network is partitioned from the early morning when congestion emerges.A modified Akaike information criterion is defined to find the optimal number of partitions.Region boundary adjustment algorithms are adopted to optimize the partitioning results to further ensure the correlation of partitions.The traffic data of Melbourne city are used to verify the effectiveness of the proposed partitioning method. 展开更多
关键词 urban road networks dynamic partitioning random walk Akaike information criterion perimeter control
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