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Distribution dynamics,regional differences,and convergence of sustainable development of cities and communities in China
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作者 Guang Yang Mingle Li Chaofeng Shao 《Chinese Journal of Population,Resources and Environment》 2024年第4期443-454,共12页
China is one of the most populated and rapidly urbanizing countries worldwide and was among the earliest countries to integrate sustainable development into urban construction.To achieve high-quality development and i... China is one of the most populated and rapidly urbanizing countries worldwide and was among the earliest countries to integrate sustainable development into urban construction.To achieve high-quality development and implement the objectives of“Transforming Our World:The 2030 Agenda for Sustainable Development”,it is crucial to measure and analyze the current level of sustainable development of cities in China.Following the principles of relevance,scientific rigor,universality,reliability,and timeliness,this study constructs an assessment index system for sustainable development,covering seven themes corresponding to the UN Sustainable Development Goal 11.Through detailed calculations,we obtained sustainable development indices for 139 Chinese cities from 2016 to 2022 and analyzed them in three dimensions:distribution dynamics,regional differences,and convergence.The key findings are as follows.First,the level of sustainable development showed improvement,with the average score of included cities increasing by 11.88%from 2016 to 2022.Second,the level of sustainable development was relatively balanced,maintaining low Gini coefficients between 0.05 and 0.06.Third,a weak overallσconvergence feature existed,with increased differentiation in 2021.From a regional perspective,aσconvergence feature was observed in the northeastern but not in the western region.Fourth,both overall absoluteβ-convergence and conditionalβeffects were significant.Regional absoluteβ-convergence and conditionalβ-convergence were also significant.This study contributes to the literature by providing evidence of China’s urban sustainable development,offering policy insights for deepening the implementation of development goals in the future,and providing experiential reference for other developing countries to achieve sustainable development. 展开更多
关键词 Urban sustainability Sustainable Development Goal 11 Dynamic evolution of distribution regional differences Spatial convergence
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Spatial Distribution of Meteorological Factors During the Key Growth Periods of Apple Cultivation in Longdong Region of Gansu Province
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作者 Xuejiao ZHANG Meiyu LI Yunxia ZHANG 《Meteorological and Environmental Research》 2024年第5期1-6,共6页
With the ongoing development of the apple industry in the Longdong region of Gansu,this sector has emerged as a key driver for the government s initiatives aimed at increasing stable income for local residents and pro... With the ongoing development of the apple industry in the Longdong region of Gansu,this sector has emerged as a key driver for the government s initiatives aimed at increasing stable income for local residents and promoting rural revitalization.The Longdong region boasts a favorable geographical location and a suitable climatic environment,making it an ideal area for apple cultivation.This paper analyzes meteorological data from the national meteorological observatory in Longdong over the past forty years,focusing on average temperature,precipitation,sunshine duration,and relative humidity during three critical growth periods of apples.The research reveals significant differences in the distribution of meteorological conditions across these key growth stages.Notably,the average temperature is higher in the central and northern parts of the region,while lower temperatures are observed in the southwestern areas.The average daily maximum temperature tends to be higher in the northwest and lower in the central and southwestern regions.Conversely,the average daily minimum temperature demonstrates a distinct pattern,being higher in the south and lower in the north.Additionally,precipitation is more abundant in the southeast and less so in the northwest.Sunshine hours are greater in the northern and central regions,while the southwestern and northeastern areas receive fewer hours of sunlight.Finally,relative humidity is higher in the south and lower in the north. 展开更多
关键词 APPLE Longdong region Meteorological factor Spatial distribution
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Postmortem regional distribution of morphine in dependent rats 被引量:1
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作者 王惠玲 马丽霞 +1 位作者 唐承汉 赵晏 《Journal of Medical Colleges of PLA(China)》 CAS 2003年第4期230-234,共5页
Objective: Morphine concentration measured in postmortem tissues may or may not reflect antemortem concentration. We measured levels of morphine in autopsied tissues to determine whether morphine distribution in morph... Objective: Morphine concentration measured in postmortem tissues may or may not reflect antemortem concentration. We measured levels of morphine in autopsied tissues to determine whether morphine distribution in morphine-dependent rats is altered after death. Methods: Solid-phase extraction was used to extract morphine from the samples, and morphine levels were measured at 0-96 h postmortem using gas chromatography. Results: The study of the morphine dependent rats showed a significant (P<0.05) increase of morphine concentration in postmortem cardiac blood, liver tissues and kidneys tissues. A significant increase was also observed at 72 h and 96 h postmortem in the brain, while morphine levels in cardiac tissues only increased at 24 h and 96 h postmortem. These changes were associated with an observed pH rapid decrease: pH of cardiac blood dropped from 7.36±0.15 to 6.86±0.09 (P<0.01), pH of liver tissues from 6.98±0.04 to 6.34±0.03 (P<0.05). Conclusion: The postmortem regional distribution of morphine occurs in dependent rats, but different from the change that occurs in acute poisoning rats. The morphine concentration in cardiac blood and tissues tends to increase during the period of 0-96 h postmortem in dependent rats. Morphine concentration increases with pH rapid decrease. The antemortem internal amount of morphine affects its postmortem regional distribution. It appears that several mechanisms are accountable for postmortem morphine distribution. The understanding of the mechanisms and patterns may eventually lead to better choices of samples which may better represent antemortem drug levels. 展开更多
关键词 postmortem regional distribution DEPENDENCE MORPHINE RAT
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Regional Distribution of Cotton Fiber Quality in China 被引量:2
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作者 TANG Shu-rong,YANG Wei-hua(Cotton Research Institute,Chinese Academy of Agricultural Sciences Key Laboratory of Cotton Genetic Improvement,Ministry of Agriculture,Anyang,Henan 455000,China) 《棉花学报》 CSCD 北大核心 2008年第S1期125-,共1页
The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major ... The fiber quality status is very important for super quality cotton production and diverse requirements of textile industry in China.In this study,the quality of cotton fiber samples which are collected from 13 major cotton production provinces between 2001 to 2005 were analyzed.Eight quality 展开更多
关键词 regional distribution of Cotton Fiber Quality in China
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Chinese hair arsenic content background and its regional distribution
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作者 YANG Lin-sheng HOU Shao-fan +1 位作者 WANG Wu-yi TAN Jian-an(Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第1期71-76,共6页
Some 1313 hair samples from about 200 sample sites are collected. These sites cover 103 counties with different types of natural conditions and are far from cities (towns) or polluted areas.The hair As contents are an... Some 1313 hair samples from about 200 sample sites are collected. These sites cover 103 counties with different types of natural conditions and are far from cities (towns) or polluted areas.The hair As contents are analysed by hydro-atomic fluorescence spetrophotometry and the data are calculated by SPSS. The results show that Chinese hair As contents are between 0.004 and 9.999 μu/g.The median is 0.56μg/g. The arithmetic mean is (0.927±1.213) μg/g and the geometric mean is 0.571 μg/g. There are no significant differences between sexes and ages. The results of Pelson X2 and Shapio-Wilk W tests show that the As content in the same physical geographical area has a logarithm normal distribution. Hair As contents in southern China are significantly higher than that in the northern.The geometric means are 0.2~0.4 μg/g in medium-temperate zone and 0.4~0.6 μg/g in warm-temperate zone. In north-subtropical zone the hair As geometric mean increase up to 0.767 μg/g and in medium-subtropical zone, south-subtropical zone and tropical zone, it is higher than 1.00 μg/g. There is no difference between areas in the same physical geographical zone. Hair As content in Qinghai-Tibet Plateau area is also lower (the geometric mean is 0.267 μg/g). The standard level of hair As content for determining chronic Arsenism areas in China is also discussed. 展开更多
关键词 hair As content background regional distribution endemic arsenism China
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GIS Based Aroma Characteristic for Regional Distribution of Tobacco Using Kriging Interpolation Method Set in Henan Province of China
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作者 Xu Yue-qi Wang Peng-ze +5 位作者 Tao Tao Dang Xia Li Yan-zhou Wei Hui-qin Ma Wen-hui Yang Nan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2018年第4期71-78,共8页
To study the regional distribution features of aroma characteristics, the regional distribution maps of aroma characteristics of 225 tobacco leaf samples from Henan Province were drawn by Kriging interpolation method ... To study the regional distribution features of aroma characteristics, the regional distribution maps of aroma characteristics of 225 tobacco leaf samples from Henan Province were drawn by Kriging interpolation method in ArcGIS. The results showed that:(1) the aroma quality of flue-cured tobacco from Henan Province tobacco-growing areas ranged from better to slightly better and aroma quantity ranged from just a little to much. The ability of diffusiveness expressed slight to a little strong and the raw green odour, immature odour and ligneous odour were tiny;(2) there were significant differences between the aroma quality and scorched odour and no statistical differences among the aroma quantity, diffusiveness, raw green odour, ligneous odour and immature odour from different counties;(3) there were trends that scale of aroma quality increased from southwest to both north and east, aroma quantity showed a patchy distribution in space, diffusiveness decreased from east to west, scorched odour increased from west to both north and south, ligneous odour increased from north to south and green odour increased from south to north. 展开更多
关键词 tobacco leaf sensory evaluation aroma characteristic regional distribution characteristic
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Gini Index for Cities: A Preliminary Study on Regional Differences of Chinese City Size Distribution
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作者 Liu Wangbao & Zheng Bohong Department of Architecture and Urban Planing, Central South University, Changsha 410075, Hunan 《Chinese Journal of Population,Resources and Environment》 2004年第4期33-36,共4页
City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be u... City size distribution is of interest because of a number of key stylized facts, including notably Zipf's law for cities and the importance of urban primacy. But a new and more efficient method Gini index can be used for calculating regional city size distribution. This paper begins by developing a calculation method for the Gini index, dividing the whole country into 26 areas and then calculating each area's Gini index value. Based on these calculation results, this paper gives a preliminary study on regional differences of its city size distribution and the dynamics. 展开更多
关键词 Gini index city size distribution regional differences
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Retrieval and Regional Distribution Analysis of Ammonia,Sulfur Dioxide and Nitrogen Dioxide in the Urban Environment Using Ultraviolet DOAS Algorithm
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作者 Hao Chen Jie Xu +5 位作者 YiboHu Fuzhou Niu Zhiyan Li Dan Wang Guizhong Fu Chuanxin Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期1251-1262,共12页
Aiming at the in situ and mobile observation of urban environmental air pollution,a portable instrument using ultraviolet spectrum retrieval algorithm was developed based on the basis of Differential Optical Absorptio... Aiming at the in situ and mobile observation of urban environmental air pollution,a portable instrument using ultraviolet spectrum retrieval algorithm was developed based on the basis of Differential Optical Absorption Spectroscopy(DOAS)and multiple-pass cell technique.Typical trace gas pollutants,NH3,SO2,and NO2,were explored using their optical spectral characteristics in deep ultraviolet wavelength range from 210 to 215 nm.The gas concentration was retrieved by Lambert-Beer’s law and nonlinear least square method.With an optimized optical alignment,the detection limits of NH3,SO2,NO2 were estimated to be 2.2,2.3,and 36.2 ppb,respectively.The system was used in carrying out some cruise observations in Chengdu,China.During the entire period,the polluted gases showed varied distribution and typical daily average concentrations ofNH3,SO2,NO2 were 23.2,3.5,and 106.0 ppb,respectively.The contributions from different sources were analyzed combined with the HYSPLIT model.Results show that the portable DOAS system is a convenient and effective tool for regional distribution measurement and pollution source monitoring. 展开更多
关键词 Ultraviolet DOAS algorithm retrieve method white cell urban environment regional distribution
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China’s urban green innovation:Regional differences,distribution dynamics,and convergence
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作者 Yuting Xue Shumin Dong +1 位作者 Guixiu Ren Kai Liu 《Chinese Journal of Population,Resources and Environment》 2023年第4期239-248,共10页
Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above t... Urban green innovation(UGI)is essential to environmental protection,ecological conservation,and high quality economic growth.Using green patents,our study assessed the level of UGI of 287 Chinese cities at and above the prefecture level.Then,using the Dagum Gini coefficient,kernel density estimation(KDE),and con‐vergence models,we examined regional differences,distribution dynamics,and convergence of UGI across China.The study’s findings are as follows:(1)Overall,regional differences in UGI tended to narrow,and the main contributor to these differences was the difference between economic zones.(2)KDE showed that the level of UGI was rising,which was polarized within each economic zone.(3)The national UGI in economic zones other than the Northeast and Middle Yellow River Economic Zones featured significantσconvergence,while each economic zone showed absolute and conditionalβconvergence. 展开更多
关键词 Urban green innovation regional difference distribution dynamic CONVERGENCE Green patent
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Effect of Pore Morphology and Regional Distribution of Liquid Diffusion Directionality in Nonwoven Fabrics
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作者 殷炯 周倩倩 +3 位作者 纪峰 张瑞云 王妮 王永生 《Journal of Donghua University(English Edition)》 CAS 2023年第3期267-276,共10页
The effect of pore morphology and regional distribution on liquid diffusion directionality in nonwoven fabrics was investigated in this study.Pore orientation angle(POA) and pore aspect ratio(PAR) were proposed to cha... The effect of pore morphology and regional distribution on liquid diffusion directionality in nonwoven fabrics was investigated in this study.Pore orientation angle(POA) and pore aspect ratio(PAR) were proposed to characterize the pore morphology,and α-region,β-region,and αβ-region were used to describe the characteristics of the pore regional distribution.The directional characteristics of macroscopic diffusion of liquid in nonwoven fabrics were characterized by the indicator of primary diffusion orientation angle(PDOA).Ten kinds of spunlaced nonwoven fabrics were selected.Firstly,the data of pore characteristic indices of each sample were obtained through scanning electron microscope(SEM) and the image processing technology as well,and the pore regional distribution map of each sample was further acquired.Then,the PDOA of each sample was obtained through the droplet method and image processing technology.Based on the data and statistical analysis,it was found that the PDOA of a certain volume of liquid in the nonwoven fabrics presented a significant linear relationship with the average POA of the nonwoven fabrics.And the characteristics of pore distribution affected the directionality of liquid diffusion in the nonwoven fabrics.The samples with a large proportion of α-region and good distribution had prominent liquid diffusion along the direction of laying-up,and the difference in liquid diffusion of the samples was more obvious between the directions of laying-up and vertical laying-up. 展开更多
关键词 liquid diffusion ANISOTROPY pore morphology regional distribution primary diffusion orientation angle(PDOA)
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Regional Distribution and Pollution of Energy-lntensive Industries in China
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作者 龚健健 沈可挺 《China Economist》 2011年第5期93-103,共11页
This paper investigates the regional distribution and pollution of energyintensive industries in China. Through the analysis of provincial panel data collected during 1998-2008, this work estimates the drivers of poll... This paper investigates the regional distribution and pollution of energyintensive industries in China. Through the analysis of provincial panel data collected during 1998-2008, this work estimates the drivers of pollution in 30 of China's provincial-level divisions. The paper concludes that while China's energy-intensive industries are heavily distributed in eastern and central China, the speed of development toward central and western China has, in recent years, risen continuously. Industries located in eastern China do, however, remain the primary polluters in the country. Notably, regional agglomeration of energy-intensive industries plays a positive role in energy conservation and pollution control in China. This paper also finds that patterns of pollution in China follow the environmental Kuznets curve (EKC) with strong inter-provincial discrepancies. 展开更多
关键词 energy-intensive industry POLLUTION regional distribution industrial meration environmental Kuznets curve (EKC)
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Distribution characteristics of historical earthquake classes in Jiangsu Province and South Huanghai Sea region 被引量:16
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作者 田建明 徐徐 +2 位作者 谢华章 杨云 丁政 《地震学报》 CSCD 北大核心 2004年第4期432-439,共8页
According to the analysis on the characteristics of historic earthquakes in Jiangsu Province and South Huanghai Sea region, the historical earthquakes in the studied area are divided into two kinds of comparatively sa... According to the analysis on the characteristics of historic earthquakes in Jiangsu Province and South Huanghai Sea region, the historical earthquakes in the studied area are divided into two kinds of comparatively safe class and comparatively dangerous class. Then the statistical result of earthquake class, the characteristics of geo-graphical distribution and geological structures are studied. The study shows: a) In Jiangsu Province and South Huanghai Sea region, the majority of historical strong earthquakes belong to comparatively safe class, only 13.8% belong to comparatively dangerous class; b) Most historical earthquakes belong to comparatively safe class in the land area of Jiangsu, eastern sea area of Yangtze River mouth and northern depression of South Huanghai Sea region. However, along the coast of middle Jiangsu Province and in the sea area of South Huanghai Sea, the distribution of historical earthquake classes is complex and the earthquake series of comparatively dan-gerous class and comparatively safe class are equivalent in number; c) In the studied area, the statistical results of historical earthquake classes and the characteristics of spatial distribution accord very well with the real case of present-day earthquake series. It shows that the seismic activity in the region has the characteristic of succession, and the result from this study can be used as a reference for early postseismic judgment in the earthquake emer-gency work in Jiangsu Province. 展开更多
关键词 历史地震 分类原则 分布特征 江苏及南黄海
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Magnitude and distance distribution of strong aftershocks in Sichuan-Yunnan region 被引量:4
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作者 吕晓健 高孟潭 +1 位作者 高战武 米素婷 《地震学报》 CSCD 北大核心 2008年第4期397-404,共8页
研究了川滇地区1966年以来12次主震震级Ms≥6.5的地震序列中,主震与强余震(本文定义为所有Ms≥5的余震)震级差分布特征和强余震与主震距离的分布特征。结果表明,强余震与主震震级差服从截断的指数分布,据此推导出了强余震与主震震... 研究了川滇地区1966年以来12次主震震级Ms≥6.5的地震序列中,主震与强余震(本文定义为所有Ms≥5的余震)震级差分布特征和强余震与主震距离的分布特征。结果表明,强余震与主震震级差服从截断的指数分布,据此推导出了强余震与主震震级差的概率密度函数;强余震距离分布的优势范围是距主震10-39km,且强余震与主震震中的距离服从正态分布。 展开更多
关键词 川滇地区 强余震 概率分布 空间分布
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Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China 被引量:2
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作者 CUI Yulong YANG Liu +1 位作者 XU Chong ZHENG Jun 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1564-1580,共17页
In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous ter... In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corresponding rise. In terms of spatial distribution, the rainfall-triggered landslides primarily occurred in the northeastern part of the study area, particularly in regions characterized by complex topography such as Shanzao Village in Yantan Town, Xixia Township, and Shangzhang Township. The research findings offer crucial data on the rainfallinduced landslides triggered by Typhoon Lekima, shedding light on their spatial distribution patterns. These findings provide valuable references for mitigating risks and planning reconstruction in typhoon-affected area. 展开更多
关键词 Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region
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Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:1
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作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming Zhang Jiahui Cheng Qi Zhang Wei Zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome SIRT1-PGC1α regional brain distribution whole brain clearing and imaging
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Sedimentary Facies and Distribution of Reservoir Rocks from the Feixianguan Formation in the Daxian-Xuanhan Region, NE Sichuan 被引量:11
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作者 MA Yongsheng MOU Chuanlong +2 位作者 GUO Xusheng YU Qian TAN Qinyin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期137-151,共15页
The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangc... The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangcang marine basin. Outcrops, well logs and seismic data have disclosed that three sedimentary facies can be identified for the formation: open platform, platform exposed shoal and restricted platform facies. During the early stage of deposition of the Feixianguan Formation, there existed a sedimentary framework all the same as the Late Permian one: open platform in the west, and platform exposed shoal, restricted platform and open platform eastwards. The gradual increase of the shoal area permitted eastward migration of the shoal facies. During the deposition of the third member of the Feixianguan Formation, the study area was invaded by temporary transgressions. Till the deposition of the fourth member of the formation, the study area was prevailed over the unified restricted platform deposits, as indicated by the sedimentary model for the typical carbonate platform shoal deposits. The reservoir rocks in the Feixianguan Formation consist mostly of solution opening dolostone, and the rock types are assembled by oolitic dolostone, residual oolitic dolostone and sucrosic residual oolitic medium- to coarse-grained dolostone. The deep and shallow dual laterologs show relatively high resistivity, clear amplitude differences and time difference saltation of acoustic waves in some intervals. The seismic responses are indicated by low-frequency and highly variable amplitudes and chaotic reflection configurations. The reservoir rocks are characterized by high porosity-high permeability and medium porosity-medium permeability, showing a marked correlation between porosity and permeability. Solution openings are extremely developed in the reservoir rocks, including cast pores, intergranular solution openings, intercrystal pores, intercrystal solution openings, solution openings (caves) and minute fissures. Macropores and coarse pore throats are common. The reservoir rocks are apparently controlled by sedimentary facies in distribution patterns. Vertically, they occur dominantly in the second and first members of the Feixianguan Formation, and laterally in the platform exposed shoals and restricted platforms, where good natural gas potential is expected. 展开更多
关键词 Daxian-Xuanhan region Feixianguan Formation carbonate platform exposed shoal physical property distribution of reservoir rocks
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Zonal Distribution of the Erosion-Landslide and Soil Micromorphological Features in Purple Hilly Region 被引量:6
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作者 HEYurong LIAOChaolin XUPei ZHANGBaohua 《Journal of Mountain Science》 SCIE CSCD 2005年第1期42-49,共8页
In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, so... In the purple hilly region, erosions and landslides are all serious, and it is of great scientific value and practical significance to study their formation mechanism and distribution features there. In this paper, soil micromorphological methods and techniques were used to study the erosion zonal distribution in the region. The results indicated: (1) According to erosion process, the spacial distribution zones of the erosions and landslides in the purple hilly region with different solums were divided into scouring erosion zone, transport-diffusion zone, rocks and soil turbulence zone and sediment-bury zone; (2) The soil micromorphologic taxonomic feature identifying different erosion-landslide zone were found by studying the soil micromorphology of erosive zone in purple hilly region; (3) As for the erosion–landslide formation in the region, besides the external factors, the internal factors were found more important and favorable for landslide formation through the studies on the micormorphological features of slide soil. 展开更多
关键词 Purple hilly region erosion-landslide zonal distribution soil micromorphology
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Arsenic distribution and source in groundwater of Yangtze River Delta economic region, China 被引量:2
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作者 ZHOU Xun 《Journal of Groundwater Science and Engineering》 2017年第4期343-353,共11页
This thesis focuses Arsenic(As) distribution and occurrence in groundwater of Yangtze River Delta economic region, East China. 2019 groundwater samples were collected to analyze 26 chemical compositions, including As.... This thesis focuses Arsenic(As) distribution and occurrence in groundwater of Yangtze River Delta economic region, East China. 2019 groundwater samples were collected to analyze 26 chemical compositions, including As. The Principal Component Analysis(PCA) was used to find out As source in groundwater. The results show that average As concentration in groundwater of this study is 9.33 μg/l, and maximum As concentration is up to 510 μg/l. The variation coefficient is 314.34%. High arsenic phreatic water(>10 μg/l) distributes along the Yangtze River and its estuary. Weak hydrodynamic conditions, wide p H value variation range and deteriorating environment are dominating factors, especially in Yangtze River Delta. The PCA suggests that arsenic in phreatic water is mainly of natural origin. Part of arsenic may directly originate from sediment organics and be related to organics decomposition. 展开更多
关键词 GROUNDWATER ARSENIC distribution SOURCE YANGTZE River DELTA economic region
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Enhancing Autonomy Capability in Regional Power Grids:A Strategic Planning Approach with Multiple Autonomous Evaluation Indexes
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作者 Jie Ma Tong Zhao +8 位作者 Yuanzhao Hao Wenwen Qin Haozheng Yu Mingxuan Du Yuanhong Liu Liang Zhang Shixia Mu Cuiping Li Junhui Li 《Energy Engineering》 EI 2024年第9期2449-2477,共29页
After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and de... After the integration of large-scale DistributedGeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between power generation and demand in the distribution network,exacerbating the phenomenon of wind and solar power wastage.As a novel power system model,the fundamental concept of Regional Autonomous Power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of DGs.Therefore,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for autonomy.First,a regional Energy Storage(ES)configuration strategy is proposed.This strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES capacity.Then,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy capabilities.The final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on average.The proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluctuation of power exchange between the regional grid and the higher-level grid.This presents a rational and effective planning solution for the regional grid,facilitating the coordinated development between the region and the distribution network. 展开更多
关键词 regional autonomous power grid distributed generation distributed energy storage regional planning strategy evaluation index
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Remote Sensing-based Spatiotemporal Distribution of Grassland Aboveground Biomass and Its Response to Climate Change in the Hindu Kush Himalayan Region 被引量:3
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作者 XU Cong LIU Wenjun +4 位作者 ZHAO Dan HAO Yanbin XIA Anquan YAN Nana ZENG Yuan 《Chinese Geographical Science》 SCIE CSCD 2022年第5期759-775,共17页
The grassland in the Hindu Kush Himalayan(HKH) region is one of the large st and most biodiverse mountain grassland types in the world,and its ecosystem service functions have profound impacts on the sustainable devel... The grassland in the Hindu Kush Himalayan(HKH) region is one of the large st and most biodiverse mountain grassland types in the world,and its ecosystem service functions have profound impacts on the sustainable development of the HKH region.Monitoring the spatiotemporal distribution of grassland aboveground biomass(AGB) accurately and quantifying its response to climate change are indispensable sources of information for sustainably managing grassland ecosystems in the HKH region.In this study,a pure vegetation index model(PVIM) was applied to estimate the long-term dynamics of grassland AGB in the HKH region during 2000-2018.We further quantified the response of grassland AGB to climate change(temperature and precipitation) by partial correlation and variance partitioning analyses and then compared their differences with elevation.Our results demonstrated that the grassland AGB predicted by the PVIM had a good linear relationship with the ground sampling data.The grassland AGB distribution pattern showed a decreasing trend from east to west across the HKH region except in the southern Himalayas.From 2000 to 2018,the mean AGB of the HKH region increased at a rate of 1.57 g/(m~2·yr) and ranged from 252.9(2000) to 307.8 g/m~2(2018).AGB had a positive correlation with precipitation in more than 80% of the grassland,and temperature was positively correlated with AGB in approximately half of the region.The change in grassland AGB was more responsive to the cumulative effect of annual precipitation,while it was more sensitive to the change in temperature in the growing season;in addition,the influence of climate varied at different elevations.Moreover,compared with that of temperature,the contribution of precipitation to grassland AGB change was greater in approximately 60% of the grassland,but the differences in the contribution for each climate factor were small between the two temporal scales at elevations over 2000 m.An accurate assessment of the temporal and spatial distributions of grassland AGB and the quantification of its response to climate change are of great significance for grassland management and sustainable development in the HKH region. 展开更多
关键词 grassland aboveground biomass(AGB) climate change ELEVATION spatiotemporal distribution Hindu Kush Himalayan(HKH)region
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