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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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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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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 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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THE DISTRIBUTION REGION AND THE DISTRIBUTIVE TEMPERATURE AND HUMIDITY THRESHOLD OF OSIER WEEVIL IN CHINA
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作者 段立清 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第2期50-53,共4页
A distribution map of osier weevil (Crytorrynchus lapathi L.) was drown up based on widely collecting information and field survey. The results showed that Osier weevil has a widespread in China, stretching from 33&#... A distribution map of osier weevil (Crytorrynchus lapathi L.) was drown up based on widely collecting information and field survey. The results showed that Osier weevil has a widespread in China, stretching from 33°21' to 51°42' N latitude and 83°00' to 132°58' E longitude, and distributes in forms of big or small patches or sports uncontinously. According to the analysis of meteorological data, the temperature and humidity threshold for osier weevil's distribution were determined by methods of PCA (Principle Component Analysis) and RA(Relativity Analysis): January temperature is -30~ 0℃. Annual temperature -4~13℃, Annual precipitation from 411~ 1,136 min.The areas with January temperature under 0℃, annual temperature above 0℃ and annual precipitation of 400~ 800 mm are the optimum distributing places for osier weevil in China. 展开更多
关键词 Osier weevil Cryptorrynchus lapath distribution region Temperature and humidity threshold
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面向山区铁路工程物流基地选址的分布鲁棒优化模型
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作者 王浩 甘蜜 +3 位作者 魏力飞 何庆 王平 彭涛 《铁道学报》 EI CAS CSCD 北大核心 2024年第1期103-112,共10页
山区铁路传统工程建设运输物流基地选址模型较少将未来可能需求纳入考量范畴,忽视了此类临时工程在社会效益方面的可持续发展潜力。针对此问题,在传统工程建设运输物流基地选址模型考虑影响因素及假设基础上,加入永临结合决策变量,构建... 山区铁路传统工程建设运输物流基地选址模型较少将未来可能需求纳入考量范畴,忽视了此类临时工程在社会效益方面的可持续发展潜力。针对此问题,在传统工程建设运输物流基地选址模型考虑影响因素及假设基础上,加入永临结合决策变量,构建同时考虑未来社会需求分布的不确定性的工程选址模型。以工程地质条件、建设施工成本、道路情况等多个因素作为评价指标,采用预测未来社会需求并引入波动变量构建非精确机会约束的方式,提出适用于永临结合模式设施选址的“多面体-DRO”二阶段分布鲁棒模型。研究结果表明:服务水平是选址决策的主要影响因素;对于高海拔施工点,选择附近的高海拔设施更加可靠;为尽可能服务高海拔地区,永久设施点更倾向于在高海拔地区修建。建立的模型能够有效抵抗不确定性带来的代价,从而避免决策失误,在山区铁路工程永临结合设施修建方面有着重要理论价值和实际指导意义。 展开更多
关键词 山区铁路 设施选址 永临结合 分布鲁棒优化
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数据中心集群灵活边界下电力系统分布鲁棒优化调度方法
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作者 张锞 王旭 +1 位作者 杨宏坤 蒋传文 《电力系统自动化》 EI CSCD 北大核心 2024年第7期235-247,共13页
分布式资源的广泛接入与风、光等不可调资源的波动性使电力系统运行调控的难度显著增加。文中研究可再生能源不确定性影响下的分布式集群资源优化调度策略,挖掘多种可调资源灵活性,提高不可调资源利用率。为实现分布式可调资源的灵活调... 分布式资源的广泛接入与风、光等不可调资源的波动性使电力系统运行调控的难度显著增加。文中研究可再生能源不确定性影响下的分布式集群资源优化调度策略,挖掘多种可调资源灵活性,提高不可调资源利用率。为实现分布式可调资源的灵活调控,首先,提出了数据中心与光储集群聚合体的可调潜力时变边界计算方法,保证其聚合最优性与分解可行性。然后,基于历史数据构建契合风电随机特性的∞-Wasserstein模糊集,该方法具有良好的样本外信息描述能力。最后,提出自适应多面逼近方法解决分布鲁棒优化问题固有的无限维求解难题,将两阶段分布鲁棒调度模型转化为有限维问题以实现快速求解,并基于修改的IEEE-RTS 24节点系统仿真验证了所提方法的有效性。 展开更多
关键词 可调度域 风电消纳 分布鲁棒优化 近似求解
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Study on the regional deviation of the mac-roscopic epicenters from relevant epicenters by rapid determination in Chinese mainland
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作者 刘吉夫 王晓青 +1 位作者 陈颙 黄辅琼 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第1期39-43,共5页
The primary results have been obtained by the analyses on the deviation of macroscopic epicenters from relevant microscopic epicenters determined rapidly after the 139 earthquake events occunrred during 1989-2004. Fur... The primary results have been obtained by the analyses on the deviation of macroscopic epicenters from relevant microscopic epicenters determined rapidly after the 139 earthquake events occunrred during 1989-2004. Further study has proved the normal distributions exist in both the east and west parts of Chinese mainland partitioned along meridian 105°E. The empirical two-dimensional normal distribution functions for the deviations are presented in the paper. The results are of significance in reducing uncertainty of losses assessment immediately after a destroyed earthquake. 展开更多
关键词 Chinese mainland macroscopic epicenter microscopic epicenter regional two-dimensional normal distribution uncertainty
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考虑风电不确定性和相关性的多区域电网分布鲁棒经济调度 被引量:27
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作者 李运龙 李志刚 郑杰辉 《电力自动化设备》 EI CSCD 北大核心 2021年第8期97-104,共8页
目前基于矩的分布鲁棒优化方法没有很好地考虑风电不确定参数间的相关性导致方法比较保守。考虑风电的不确定性和相关性,使用主元分析方法构建基于矩的分布鲁棒多区域电网经济调度模型的降维模糊集。将原始模型转化为半定规划模型,并采... 目前基于矩的分布鲁棒优化方法没有很好地考虑风电不确定参数间的相关性导致方法比较保守。考虑风电的不确定性和相关性,使用主元分析方法构建基于矩的分布鲁棒多区域电网经济调度模型的降维模糊集。将原始模型转化为半定规划模型,并采用延迟约束生成算法进行求解。算例仿真结果表明所提方法可以提高计算效率以及降低电网成本。 展开更多
关键词 多区域经济调度 分布鲁棒优化 不确定性 相关性 主元分析
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Urban Expansion of China from the 1970s to 2020 Based on Remote Sensing Technology 被引量:3
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作者 LIU Fang ZHANG Zengxiang +8 位作者 ZHAO Xiaoli LIU Bin WANG Xiao YI Ling ZUO Lijun XU Jinyong HU Shunguang SUN Feifei WANG Yafei 《Chinese Geographical Science》 SCIE CSCD 2021年第5期765-781,共17页
Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the grow... Based on Remote Sensing (RS) and Geographical Information System (GIS) technology,urban expansion of 75 cities in China from the 1970s to 2020 was reconstructed by visual-interpretation method,which described the growing process of urban lands and its influences on local land use structures synchronously.By employing annual expansion area per city and urban expansion density,spatial-temporal characteristics and macro patterns of urban expansion were analyzed from the aspects of regional-distributions,administrative-levels and population-sizes comprehensively.Results indicate that:1) urban expansion in China was universal,distinct,persistent,periodic and fluctuating.In the past five decades,urban lands of 75 monitored cities in China expanded dramatically from 3606.26 km2 to 30 521.13 km2.2) Though urban expansion presented significant differences from the aspects of regional distribution,administrative levels,and population sizes,it exhibited a deceleration trend in the 13th Five-Year Plan among all kinds of cities.3) Cultivated lands were the first land resource for urban expansion,and 55.17% of newly-expanded urban lands appeared by encroaching this land use type.China’s urban expansion has caused sustained pressure on cultivated land protection,especially in super megacities,and the contradiction between urban expansion and cultivated land protection will always exist.4) The compactness of urban lands in China increased before 1987 and reduced in the next three decades,which was consistent with the implementation of major policies and the deployment of national strategies,and is expected to become compact with a stopping declining or even rebounding after the 13th Five-Year Plan. 展开更多
关键词 urban expansion PATTERN regional distribution administrative level population sizes Remote Sensing(RS) China
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Temporal and Spatial Characteristics of Wave Energy Resources in Sri Lankan Waters over the Past 30 Years 被引量:1
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作者 YANG Shaobo XI Lintong +1 位作者 LI Xingfei ZHENG Chongwei 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第3期489-500,共12页
For the survival and development of‘One Belt,One Road’,the present work aimed to evaluate the current situation of wave energy resources around Sri Lankan(SL)waters.Thirty-year ERA-Interim wind data were used to dri... For the survival and development of‘One Belt,One Road’,the present work aimed to evaluate the current situation of wave energy resources around Sri Lankan(SL)waters.Thirty-year ERA-Interim wind data were used to drive the third-generation wave model WAVEWATCH-III,and the seasonal and regional distribution characteristics of wave energy resources in SL waters were analyzed.Furthermore,the optimal season and region that contribute most to wave power in the study area were determined.On the basis of 30-year hindcast wave data,the significant wave height and wave power density,the occurrence of available SWH and rich WPD,the effective storage of wave energy,and the contribution and stability of wave energy were also analyzed.Results show that extremely optimistic wave energy resources are found at the western,southern,and southeastern waters of SL;moreover,the period of June,July,August(JJA)has great advantages in terms of the overall level of WPD,wave energy effective storage,and the contribution rate of wave energy.In addition,the wave energy during JJA is more stable than that of other periods and thus is benefi-cial to the transformation and development of wave energy.This study also provides important guiding value for disaster prevention and reduction,coastal zone management,and coastal development in the crucial region of the 21st Century Maritime Silk Road. 展开更多
关键词 Sri Lanka wave energy ERA-INTERIM WAVEWATCH-III seasonal and regional distribution
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Analysis of the negative effects of groundwater exploitation on geological environment in Asia 被引量:1
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作者 ZHANG Jian-kang WEN Xue-ru +2 位作者 GAO Yun YUE Chen YI Qing 《Journal of Groundwater Science and Engineering》 2015年第2期202-212,共11页
This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are genera... This paper summarizes the negative effects on geological environment caused by groundwater exploitation and its distribution. There are seven main types of the geological environment negative effects, which are generally as follows:(1) Constant decrease of groundwater level is mainly distributed in China(East Asia), India(South Asia), Tajikistan(Central Asia) and Saudi Arabia(West Asia);(2) land subsidence occurs mainly in eastern plains of East Asia and west Siberian Plain of North Asia;(3) seawater intrusion occurs mainly in China, Japan and South Korea in East Asia, Philippines and Indonesia in Southeast Asia, the Indian coastal areas in South Asia;(4) groundwater level decline caused by groundwater exploitation in oil fields;(5) mining collapse is mainly in 50° to 70° north latitude band;(6) the total area of karst collapse in China of East Asia is as much as 197.05 km^2; and(7) ground fracture is mainly distributed in the North China Plain, Fenwei Plain and the Yangtze River Delta. Asia can be divided into 6 zones in terms of the geological environment negative effect caused by groundwater exploitation. According to analysis, with the increasing intensity of human activities, geological environment issues become more and more serious, therefore it is vital to control the human activities within the scope of 5× 10~5 people/km^2 to 9.9× 10~5 people/km^2 for the effective control of the size of the affected area by geological environment problems. 展开更多
关键词 ASIA Groundwater development Geological environment negative effect and distributed regions Severity of geological environment problems
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Upper Mantle Heterogeneity in Ore-Forming Elements and Its Bearing on Metallogenesis in Qinling Belt and East China
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作者 Han Yinwen Zheng Haifei Ouyang Jianping Zhang BenrenChina University of Geosciences , Wuhan 430074 《Journal of Earth Science》 SCIE CAS CSCD 1992年第1期34-42,共9页
This paper presents the results of our recent studies on the upper mantle composition in the Qinling Belt and East China . It discusses the methods of estimating the upper mantle composition, its selected elements and... This paper presents the results of our recent studies on the upper mantle composition in the Qinling Belt and East China . It discusses the methods of estimating the upper mantle composition, its selected elements and its constitution characteristics .The results indicate that ore-forming elements on ore types and their distribution in this area are strongly controlled by the upper mantle heterogeneity . 展开更多
关键词 regional upper mantle partial melting ore-forming elements chemical heterogeneity regional ore distribution .
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SIMULATION OF THE SPATIAL DISTRIBUTION OF CLIMATIC ELEMENTS IN MOUNTAINOUS REGIONS 被引量:1
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作者 傅抱璞 《Acta meteorologica Sinica》 SCIE 1989年第5期669-676,共8页
In this paper,an effective method of simulating the spatial distribution of climatic elements in mountainous areas by using the semi-empirical theory is presented.As an example,the spatial distributions of temperature... In this paper,an effective method of simulating the spatial distribution of climatic elements in mountainous areas by using the semi-empirical theory is presented.As an example,the spatial distributions of temperature, vapor pressure,relative humidity,wind speed and precipitation in the Jianyang region and the Shaxi basin of Fujian Province are computed with this method,and the simulated results are in good agreement with the observations. 展开更多
关键词 SIMULATION OF THE SPATIAL distribution OF CLIMATIC ELEMENTS IN MOUNTAINOUS regionS
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Epidemiological characteristics of 369 tuberculosis patients with multidrug resistance inHainan Island: A cross-sectional study
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作者 Xiu-Juan Zhao Lin Liu +4 位作者 Xing-Yong Wu Hui-Min Fu Biao Liu Hua Pei Qian-Feng Xia 《Journal of Hainan Medical University》 2022年第3期6-10,共5页
Objective:To investigate the epidemic characteristics of multidrug resistant tuberculosis in Hainan,China,to provide basic information and theories for the prevention and control of multidrug resistant tuberculosis.Me... Objective:To investigate the epidemic characteristics of multidrug resistant tuberculosis in Hainan,China,to provide basic information and theories for the prevention and control of multidrug resistant tuberculosis.Methods:A retrospective descriptive epidemiological study was conducted.Data of multidrug resistant tuberculosis in Hainan Island from January 1,2014 to December 31,2019 were collected for statistical analysis.The counting data were described by frequency(percentage),and the measurement data were described by mean±standard deviation.Chi square test was used to compare the differences between different groups.If P<0.05,the difference was statistically significant.Results:From 2014 to 2019,the multidrug resistant rate of tuberculosis in Hainan Island was 24.9%(369/1484),8.0%(63/791)in newly-treated tuberculosis,and 44.2%(306/693)in retreatedmultidrug resistant rate of tuberculosis in Hainan Island was 24.9%(369/1484),8.0%(63/791)in newly-treatedtuberculosis,and 44.2%(306/693)in retreated tuberculosis.The multidrug resistant rate of newly-treated tuberculosis decreased by 0.05%per year,while that of retreated tuberculosis increased by 0.03%per year.multidrug resistant tuberculosis was mainly distributed in the city of Haikou(83 cases),Danzhou(44 cases),Wenchang(42 cases),Wanning(37 cases)and Dongfang(32 cases),accounting for 64.5%of all multidrug resistant tuberculosis.Among 369 multidrug resistant tuberculosis,81.0%were male.The proportion of newly-treated cases was 17.1%(63/369),while the proportion of retreated cases was 82.9%(306/369),which was significantly higher than that of newly-treated cases.The multidrug resistant rate of tuberculosis in different years was different.Conclusion:The drug resistance rate of tuberculosis in Hainan Island is higher than the national average level,which needs attention.The epidemiological characteristics of multidrug resistant tuberculosis with different treatment history were different. 展开更多
关键词 Mycobacterium tuberculosis Multi-drug resistant tuberculosis Time distribution regional distribution Population distribution
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Compilation of hydrogeological map of China
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作者 ZHANG Jian-kang DONG Hua +2 位作者 CHENG Yan-pei YUE Chen LIU Kun 《Journal of Groundwater Science and Engineering》 2020年第4期381-395,共15页
Hydrogeological map is one of the important carriers of groundwater related information.It directly reflects the hydrogeological conditions and previous investigation and research results of a mapping area.The hydroge... Hydrogeological map is one of the important carriers of groundwater related information.It directly reflects the hydrogeological conditions and previous investigation and research results of a mapping area.The hydrogeological map of China is a map reflecting the characteristics of hydrogeology and groundwater dynamics on a national scale.On the basis of the hydrogeological map of China(1:4000000)compiled in 1988,this map compilation attempted to update and enhance the existing map,with the latest survey results from the project of National Investigation and Evaluation of Groundwater Resources and Environmental Problems led by China Geological Survey.Task of the mapping program included redefining groundwater types,quantifying the classification standard of the groundwater and adding the pore-fissure water in laterite layer of hilly basin.The multilayer structures for porous,karst and porous-fractured groundwater and their water-rich grades are reflected on the map.Based on the comprehensive summary of the latest hydrogeological data of China,this research conducts an in-depth analysis of the regional distribution characteristics of groundwater in China,utilizes a digital mapping process and establishes a cartographic database for the purpose of further use.With the enrichment of the content and the continuous improvement of cognitive level,mapping content can be updated quickly,which has practical significance for the concept of surveying and mapping and scientific popularization. 展开更多
关键词 Hydrogeology map Mapping methods Groundwater types Water-bearing degree Groundwater regional distribution characteristics
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STUDY ON THE SEQUENCE STRUCTURE OF SBR BY ^(13)C-NMR METHOD Ⅱ. PEAK ASSIGNMENT FOR ALIPHATIC CARBONS SPECTRA
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作者 焦书科 陈晓农 +1 位作者 胡力平 严宝珍 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第1期25-35,共11页
The study on ^(13)C-NMR spectra of aliphatic carbon region of emuision-processed and solution-processed (by lithium catalyst) SBR was carried out. The assignments for more than thirty odd peaks observed experimentally... The study on ^(13)C-NMR spectra of aliphatic carbon region of emuision-processed and solution-processed (by lithium catalyst) SBR was carried out. The assignments for more than thirty odd peaks observed experimentally were made by using 'corresponding analysis' method, combined with the empirical parameters reported in literature. The peak intensifies were calculated based on BemouUian statistic assumption. 展开更多
关键词 Corresponding analysis method peak assignment for aliphatic carbon region sequence distribution of SBR empirical parameter method.
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Changes of Precipitation Intensity Spectra in Different Regions of China's Mainland During 1961-2006 被引量:11
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作者 江志红 沈雨辰 +2 位作者 马婷婷 翟盘茂 方思达 《Journal of Meteorological Research》 SCIE 2014年第6期1085-1098,共14页
The spectral characteristics of precipitation intensity during warm and cold years are compared in six regions of China based on precipitation data at 404 meteorological stations during 1961-2006.In all of the studied... The spectral characteristics of precipitation intensity during warm and cold years are compared in six regions of China based on precipitation data at 404 meteorological stations during 1961-2006.In all of the studied regions except North China,with the increasing temperature,a decreasing trend is observed in light precipitation and the number of light precipitation days,while an increasing trend appears in heavy precipitation and the heavy precipitation days.Although changes in precipitation days in North China are similar to the changes in the other five regions,heavy precipitation decreases with the increasing temperature in this region.These results indicate that in most parts of China,the amount of precipitation and number of precipitation days have shifted towards heavy precipitation under the background of a warming climate;however,the responses of precipitation distributions to global warming differ from place to place.The number of light precipitation days decreases in the warm and humid regions of China(Jianghuai region,South China,and Southwest China),while the increasing amplitude of heavy precipitation and the number of heavy precipitation days are greater in the warm and humid regions of China than that in the northern regions(North China,Northwest China,and Northeast China).In addition,changes are much more obvious in winter than in summer,indicating that the changes in the precipitation frequency are more affected by the increasing temperature during winter than summer.The shape and scale parameters of the Γ distribution of daily precipitation at most stations of China have increased under the background of global warming.The scale parameter changes are smaller than the shape parameter changes in all regions except Northwest China.This suggests that daily precipitation shifts toward heavy precipitation in China under the warming climate.The number of extreme precipitation events increases slightly,indicating that changes in the Γ distribution fitting parameters reflect changes in the regional precipitation distribution structure. 展开更多
关键词 precipitation intensity distribution different regions Γ distribution
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