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Spatial and Temporal Distribution Characteristics of Snowstorm in Ulanqab City in Recent 30 Years
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作者 Jie CHEN Jinhua LIU 《Meteorological and Environmental Research》 2024年第4期11-14,共4页
Based on the data of daily snowfall and weather phenomena of 11 national meteorological stations in Ulanqab City from 1991 to 2020,the spatial and temporal distribution characteristics of snowstorm were analyzed.The r... Based on the data of daily snowfall and weather phenomena of 11 national meteorological stations in Ulanqab City from 1991 to 2020,the spatial and temporal distribution characteristics of snowstorm were analyzed.The results show that the snowstorm in Ulanqab had obvious seasonal distribution characteristics,mainly happening in spring(March-May)and autumn(September-November).It also had obvious regional distribution in space,and the snowstorm center appeared in Chahar Right Wing Middle Banner and Jining District,namely the east side of the Yinshan Mountain.In the past 30 years,the amount of snowstorm in the whole year in Ulanqab showed a certain fluctuation trend,and the number of snowstorm days had shown an obvious upward trend since 2011. 展开更多
关键词 Ulanqab City SNOWSTORM Spatial and temporal distribution characteristics
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Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City 被引量:1
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作者 Ruchun ZHANG Hongjun JIANG +1 位作者 Henan MENG Ruijun WANG 《Plant Diseases and Pests》 CAS 2023年第4期38-43,47,共7页
[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of publi... [Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 families.In terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the total.The most alien invasive plants were native to America,accounting for 66.1%of the total.In terms of introduction path,the plants introduced artificially and unintentionally accounted for almost half.The species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and protection.There was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and protection.Among the 56 alien invasive plants,3 plants were toxic.From the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants. 展开更多
关键词 Alien invasive plant Garden greenbelt distribution characteristics Shijazhuang City Introduction path
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Distribution Characteristics and Shielding Effects of Ion Clouds 被引量:1
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作者 Hui YANG Zhongqiu SHI +3 位作者 Renhong GUO Yixian QIU Qiaobin WEI Yu HUANG 《Meteorological and Environmental Research》 CAS 2023年第2期42-44,49,共4页
The latest research shows that the ions generated by the corona discharge of lightning rod have dual functions of attracting and shielding lightning discharge. After the lightning rod is installed at a certain height ... The latest research shows that the ions generated by the corona discharge of lightning rod have dual functions of attracting and shielding lightning discharge. After the lightning rod is installed at a certain height on the ground,the lightning rod tip reaches the corona threshold to ionize the surrounding air and generate positive and negative ions under the action of the electric field at the end of the lightning downward leader. Constrained by Coulomb’s Law,its positive ions( opposite charges attract each other) form an upward leader( streamer),which moves towards the end of the lightning downward leader and is connected to the downward leader,establishing a discharge channel to attract lightning to the needle tip and discharge the current to the ground,and playing a role in attracting lightning. Its negative ions are repelled by the electric field at the end of the lightning downward leader( repelled by isotropic charges) and influenced by the wind,and diffuse in the downwind area to form an ion cloud,inhibiting the growth of corona at the tip of ground objects,and playing a role in shielding lightning. In this paper,Franklin’s understanding of the role of lightning rod and Yang Shaojie’s new definition of the working principle of lightning rod are briefly introduced. The formation mechanism,distribution characteristics,shielding effect,and impact on lightning strike point distribution of ion clouds are analyzed. Additionally,the important role of shielding effects of ion clouds in regional lightning protection is introduced,which provides a theoretical basis for the correct understanding and use of lightning rod. 展开更多
关键词 Lightning rod Ion clouds distribution characteristics Regional lightning protection Theoretical basis
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Study on Distribution Characteristics and Occurrence Form of Soil Fluorine in Sorghum Base of Renhuai City
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作者 Ziping PAN Maoyan SHAO +2 位作者 Xubin HUANG Ting CHEN Luyao SUI 《Agricultural Biotechnology》 CAS 2023年第1期66-71,共6页
In order to find out the effects of soil fluorine on ecological environment and crop safety in the sorghum cultivation base of Renhuai City, Guizhou Province, the content and the occurrence forms of soil fluorine and ... In order to find out the effects of soil fluorine on ecological environment and crop safety in the sorghum cultivation base of Renhuai City, Guizhou Province, the content and the occurrence forms of soil fluorine and its influencing factors of Maoba Town were investigated and studied. The results showed that the total fluorine content in the soil of the sorghum base ranged from 668.60 to 2 596.80 mg/kg, with an average of 1 483.25 mg/kg, which was 3.10 and 1.85 times of the national soil background value and the average value of the soil in endemic areas, respectively. The spatial distribution of fluorine in the soil of the study area was uneven, and the fluorine content was in the order of Anliang Village>Yangliu Village>Houba Village>Xiongfeng Village. The soil fluorine contents of various forms varied greatly, and the distribution law was as follows: residual state>water soluble state>organically bound state>exchangeable state>Fe/Mn-F state. The residual fluorine content was the highest, accounting for more than 99% of total fluorine content, while the sum of other four forms was less than 1%, with their respective proportions ranging from 0.10% to 0.30%. The content and proportion of available fluorine in water-soluble and exchangeable states were relatively low, which had limited influence on the surrounding water environment and crop safety. The physicochemical properties of soil, such as pH, organic matter, cation exchange capacity and clay particles had a certain influence on the occurrence forms of soil fluorine, thus changing the availability and migration of soil fluorine, which might endanger the ecological environment safety, food safety and human health. 展开更多
关键词 Sorghum base Soil Fluorine Occurrence form distribution characteristics Renhuai City
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Enrichment conditions and distribution characteristics of lacustrine medium-to-high maturity shale oil in China
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作者 ZHAO Wenzhi ZHU Rukai +2 位作者 LIU Wei BIAN Congsheng WANG Kun 《地学前缘》 EI CAS CSCD 北大核心 2023年第1期242-259,共18页
Successful breakthroughs have been made in shale oil exploration in several lacustrine basins in China,indicating a promising future for shale oil exploration and production.Current exploration results have revealed t... Successful breakthroughs have been made in shale oil exploration in several lacustrine basins in China,indicating a promising future for shale oil exploration and production.Current exploration results have revealed the following major conditions of lacustrine shale oil accumulation:(1)stable and widely distributed shale with a high organic abundance and appropriate thermal maturity acts as a fundamental basis for shale oil retention.This shale exhibits several critical parameters,such as total organic carbon content greater than 2%,with optimal values ranging from 3% to 4%,kerogen Ⅰ and Ⅱ_(1) as the dominant organic matter types,and vitrinite reflectance(R_(o))values greater than 0.9%(0.8% for brackish water environments).(2)Various types of reservoirs exhibiting brittleness and a certain volume of micro-nanoscale pores are critical conditions for shale oil accumulation,and these reservoirs have porosities greater than 3% to 6%.Moreover,when diagenesis is incipient,pure shales are not favorable for medium-to-high maturity shale oil enrichment,whereas tight sandstone and hybrid rocks with clay content less than 20% are favorable;however,for medium-to-late-stage diagenesis,pure shales with a clay content of 40% are favorable.(3)The retention of a large amount of high-quality hydrocarbons is the factor that best guarantees shale oil accumulation with good mobility.Free hydrocarbon content exceeding a threshold value of 2 mg/g is generally required,and the optimum value is 4 mg/g to 6 mg/g.Moreover,a gas-oil ratio exceeding a threshold value of 80 m^(3)/m^(3) is required,with the optimal value ranging from 150 m^(3)/m^(3) to 300 m^(3)/m^(3).(4)High-quality roof and floor sealing conditions are essential for the shale oil enrichment interval to maintain the overpressure and retain a sufficient amount of hydrocarbons with good quality.Lacustrine shale oil distributions exhibit the following characteristics:(1)major enrichment areas of shale oil are located in semi-deep to deep lacustrine depositional areas with external materials,such as volcanic ash fallout,hydrothermal solutions,and radioactive substances with catalytic action,as inputs;(2)intervals with“four high values and one preservation condition”govern the distribution of shale oil enrichment intervals;and(3)favorable assemblages of lithofacies/lithologies determine the distribution of enrichment area.According to preliminary estimates,China has 131×10^(8) to 163×10^(8) t of total shale oil resources with medium-to-high thermal maturity,among which 67×10^(8) to 84×10^(8) t is commercial.These resources are primarily located in the Chang 7^(1+2) interval in the Ordos Basin,Qing 1+2 members in Gulong sag in the Songliao Basin,Kongdian and Shahejie formations of Cangdong sag,Qikou sag and the Jiyang depression in the Bohai Bay Basin,and Lucaogou Formation in the Junggar Basin. 展开更多
关键词 medium-to-high maturity shale oil sweet-spot zone enrichment conditions distributional characteristics assessment standard onshore China
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Distribution Characteristics of COD in the Waters of Pearl River Estuary 被引量:2
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作者 杨美兰 林钦 +7 位作者 黄洪辉 甘居利 蔡文贵 吕晓瑜 王增焕 李纯厚 杜飞雁 胡德蓉 《Marine Science Bulletin》 CAS 2006年第1期68-74,共7页
The surveys on the COD in the Lingdingyang waters of Pearl River estuary were carried out in May and August of 2002. The results showed that the concentrations of COD in the waters ranged from 0,41 to 2.72 mg·L^-... The surveys on the COD in the Lingdingyang waters of Pearl River estuary were carried out in May and August of 2002. The results showed that the concentrations of COD in the waters ranged from 0,41 to 2.72 mg·L^-1 with an average of 1.21 mg·L^-1.The spatial distributions showed that COD concentration decreased gradually from the north to south of Pearl River estuary, and the concentration near coastal waters was higher than that in offshore waters. The concentration of COD in summer was higher than in spring. Evaluated by the first class (COD ≤ 2 mg·L^-1) of sea water quality standard (Chinese standard), there were about 15 % of COD concentrations over the standard. The concentration of COD showed a positive correlation with the concentration of suspend substances in spring and summer, but in summer it showed a negative correlation with the concentrations of inorganic nitrate and phosphate. 展开更多
关键词 COD Pearl River estuary distribution characteristics
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Study on Distribution Characteristics of Lightning Disasters in Hebei Province 被引量:3
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作者 王建恒 杨仲江 吴孟恒 《Meteorological and Environmental Research》 CAS 2010年第7期105-108,共4页
Based on the special landscape and regional characteristics,the lightning location information from 1999 to 2008 and conventional observation data from 1971 to 2000 provided by electricity departments in Hebei Provinc... Based on the special landscape and regional characteristics,the lightning location information from 1999 to 2008 and conventional observation data from 1971 to 2000 provided by electricity departments in Hebei Province were applied to analyze spatial and temporal distribution of lightning.With lighting disaster data since 2000 provided by meteorological department,and records from civil affair,statistics,insurance,and other departments,the lighting disaster distribution of Hebei Province was studied from aspects of economic and people losses,and some countermeasures for several lightning disasters industries were put forward. 展开更多
关键词 Lightning disasters distribution characteristics RESEARCH China
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Distribution characteristics of dissolved organic carbon in annular wetland soil-water solutions through soil profiles in the Sanjiang Plain,Northeast China 被引量:15
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作者 XI Min LU Xian-guo +1 位作者 LI Yue KONG Fan-long 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1074-1078,共5页
Overwhelming evidence reveals that concentrations of dissolved organic carbon (DOC) have increased in streams which brings negative environmental impacts. DOC in stream flow is mainly originated from soil-water solu... Overwhelming evidence reveals that concentrations of dissolved organic carbon (DOC) have increased in streams which brings negative environmental impacts. DOC in stream flow is mainly originated from soil-water solutions of watershed. Wetlands prove to be the most sensitive areas as an important DOC reserve between terrestrial and fluvial biogeosystems. This reported study was focused on the distribution characteristics and the controlling factors of DOC in soil-water solutions of annular wetland, i.e., a dishing wetland and a forest wetland together, in the Sanjiang Plain, Northeast China. The results indicate that DOC concentrations in soilwater solutions decreased and then increased with increasing soil depth in the annular wetland. In the upper soil layers of 0-10 cm and 10-20 cm, DOC concentrations in soil-water solutions linearly increased from edge to center of the annular wetland (R^2 = 0.3122 and R^2 = 0.443). The distribution variations were intimately linked to DOC production and utilization and DOC transport processes in annular wetland soil-water solutions. The concentrations of total organic carbon (TOC), total carbon (TC) and Fe(II), DOC mobility and continuous vertical and lateral flow affectext the distribution variations of DOC in soil-water solutions. The correlation coefficients between DOC concentrations and TOC, TC and Fe(II) were 0.974, 0.813 and 0.753 respectively. These distribution characteristics suggested a systematic response of the distribution variations of DOC in annular wetland soil-water solutions to the geometry of closed depressions on a scale of small catchments. However, the DOC in soil pore water of the annular wetland may be the potential source of DOC to stream flow on watershed scale. These observations also implied the fragmentation of wetland landscape could bring the spatial-temporal variations of DOC distribution and exports, which would bring negative environmental impacts in watersheds of the Sanjiang Plain. 展开更多
关键词 dissolved organic carbon (DOC) distribution characteristics annular wetland soil-water solutions Sanjiang Plain
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Temporal and spatial distribution characteristics of water resources in Guangdong Province based on a cloud model 被引量:9
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作者 Qi Zhou Wei Wang +2 位作者 Yong Pang Zhi-yong Zhou Hui-ping Luo 《Water Science and Engineering》 EI CAS CSCD 2015年第4期263-272,共10页
With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distr... With a focus on the difficulty of quantitatively describing the degree of nonuniformity of temporal and spatial distributions of water resources, quantitative research was carried out on the temporal and spatial distribution characteristics of water resources in Guangdong Province from 1956 to 2000 based on a cloud model. The spatial variation of the temporal distribution characteristics and the temporal variation of the spatial distribution characteristics were both analyzed. In addition, the relationships between the numerical characteristics of the cloud model of temporal and spatial distributions of water resources and precipitation were also studied. The results show that, using a cloud model, it is possible to intuitively describe the temporal and spatial distribution characteristics of water resources in cloud images. Water resources in Guangdong Province and their temporal and spatial distribution characteristics are differentiated by their geographic locations. Downstream and coastal areas have a larger amount of water resources with greater uniformity and stronger stability in terms of temporal distribution. Regions with more precipitation possess larger amounts of water resources, and years with more precipitation show greater nonuniformity in the spatial distribution of water resources. The correlation between the nonuniformity of the temporal distribution and local precipitation is small, and no correlation is found between the stability of the nonuniformity of the temporal and spatial distributions of water resources and precipitation. The amount of water resources in Guangdong Province shows an increasing trend from 1956 to 2000, the nonuniformity of the spatial distribution of water resources declines, and the stability of the nonuniformity of the spatial distribution of water resources is enhanced. 展开更多
关键词 Water resources Temporal and spatial distribution characteristics Cloud model Guangdong Province
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Distribution Characteristics of Cobalt-rich Ferromanganese Crust Resources on Submarine Seamounts in the Western Pacific 被引量:6
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作者 ZHANG Fuyuan ZHANG Weiyan +4 位作者 ZHU Kechao GAO Shuitu ZHANG Haisheng ZHANG Xiaoyu ZHU Benduo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第4期796-803,共8页
Based on the survey data of five submarine seamount provinces (chains) in the Western Pacific, the distribution characteristics of cobalt-rich ferromanganese crust resources have been researched in this paper by usi... Based on the survey data of five submarine seamount provinces (chains) in the Western Pacific, the distribution characteristics of cobalt-rich ferromanganese crust resources have been researched in this paper by using the relative reference data and applying the theories of hotspot and seafloor spreading. The main research results obtained are as follows: The Co-rich crust thickness in the study area is gradually increasing from east to west and from south to north having a negative correlation (r = -0.59) with longitude and a positive correlation (r = 0.48) with latitude. The crust thickness varying along longitude and latitude is influenced by the hotspot and seafloor spreading. The oceanic crusts and seamounts in the northwest part of the study area are older, and the crust resources are superior to those in the southeast part. In the depth of 〈1500 m, 1500-2000 m, 2000-2500 m in the study area, the cobalt crust thickness is respectively 5.45 cm, 4.34 cm and 3.55 cm, and in the depth of 2500-3000 m and 3000-3500 m, it drops respectively to 2.84 cm and 3.37 cm. The Co-rich crust resources are mainly concentrated in the seamount summit margins and the upper flanks in the depth of 〈2500 m. There is a strong negative correlation (r = -0.67) between the cobalt crust abundance and the slope of the seamount, 75 kg/m^2 and 50 kg/mz at the slopes of 0°-20° and 20°-34° respectively. Cobalt crusts are mainly distributed in the parts whose slopes are less than 20°. It is consistent with the fractal result that the slope threshold of cobalt crust distribution is 19°, and slopes over 20° are not conducive to the crust growth. The cobalt crusts of high grade are mainly enriched in the region within 150°E-140°W and 30°S-30°N in the Pacific, where there are about 587 seamounts at the depth of 3500- 6000 m and over 30 Ma of the oceanic crusts. The perspective area rich in cobalt crust resources is about 41×104 km^2 and the resource quantity is approximately 27 billion tons. 展开更多
关键词 Western Pacific SEAMOUNTS Co-rich crusts RESOURCES distribution characteristics
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Distribution characteristics and impact on pump's efficiency of hydro-mechanical losses of axial piston pump over wide operating ranges 被引量:4
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作者 XU Bing HU Min +1 位作者 ZHANG Jun-hui MAO Ze-bing 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期609-624,共16页
A novel performance model of losses of pump was presented,which allows an explicit insight into the losses of various friction pairs of pump.The aim is to clarify that to what extent the hydro-mechanical losses affect... A novel performance model of losses of pump was presented,which allows an explicit insight into the losses of various friction pairs of pump.The aim is to clarify that to what extent the hydro-mechanical losses affect efficiency,and to further gain an insight into the variation and distribution characteristics of hydro-mechanical losses over wide operating ranges.A good agreement is found in the comparisons between simulation and experimental results.At rated speed,the hydro-mechanical losses take a proportion ranging from 87% to 89% and from 68% to 97%,respectively,of the total power losses of pump working under 5 MPa pressure conditions,and 13% of full displacement conditions.Furthermore,within the variation of speed ranging from 48% to 100% of rated speed,and pressure ranging from 14% to 100% of rated pressure,the main sources of hydro-mechanical losses change to slipper swash plate pair and valve plate cylinder pair at low displacement conditions,from the piston cylinder pair and slipper swash plate pair at full displacement conditions.Besides,the hydro-mechanical losses in ball guide retainer pair are found to be almost independent of pressure.The derived conclusions clarify the main orientations of efforts to improve the efficiency performance of pump,and the proposed model can service for the design of pump with higher efficiency performance. 展开更多
关键词 axial piston pump EFFICIENCY hydro-mechanical losses digital prototyping distribution characteristics over wideoperating ranges
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Distribution Characteristics and Influencing Factors of Geological Hazards in Tibet 被引量:5
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作者 FAN Jihui WU Caiyan Cheng Genwei 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期806-812,共7页
Tibet is one of the areas with most serious geological hazards in China, and the distribution of disasters has obvious local charac teristics. Tibet can be classified as three parts through zoning the danger degree, t... Tibet is one of the areas with most serious geological hazards in China, and the distribution of disasters has obvious local charac teristics. Tibet can be classified as three parts through zoning the danger degree, the mountain canyon high danger zone of east and southeast Tibet, the plateau mountain lake basin and valley middle danger zone of south Tibet, and the Plateau Mountain lake basin low danger zone of south Tibet. This paper takes the debris flow, collapse, landslide as the key points to analyze the distribution characteristics of geological hazards, and analyze the factors which influence the distribution of geological hazards, such as terrain landform, formation lithology, geologic structure pattern, precipitation, earthquake, human activity and so on. finally, as a conclusion., in whole Tibet, the geological hazards are more in southeast than in northwest, more in mountainous area which in the edge of plateau and river valley than in the interior of plateau and lake basin. And most hazards distribute in the regions where human activity is stronger than in other regions, for example towns or strips along the highway. 展开更多
关键词 TIBET geological hazards distribution characteristics influencing factors
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Distribution characteristics of heavy metals in surface sediments and core sediments of the Shenzhen Bay in Guangdong Province,China 被引量:4
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作者 ZUO Ping WANG Yaping MIN Fengyang CHENG Jun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第6期53-60,共8页
The concentration of zinc, chromium, cadmium, nickel, lead and copper was measured on both surface sediments and core sediments in the Shenzhen Bay. The average contents of all metals have exceeded the background valu... The concentration of zinc, chromium, cadmium, nickel, lead and copper was measured on both surface sediments and core sediments in the Shenzhen Bay. The average contents of all metals have exceeded the background values in the coastal zone of Guangdong Province. Cadmium is a heavy pollution matter which indicates a strong pollution level according to the ecological risk coefficient method. The ecological risk index of the whole area is 299 which belongs to middle and strong level. The area with strong pollution level is the near shore area closing to the inside of Shenzhen Bay, Shakou area is in the middle level while the weak pollution level occurs in Shenzhenhe Estuary according to ecological risk index. The four sediment cores can be divided into two parts based on lead-210 dating, sediments size analysis and economic development period in surrounding areas since 1950 with strong human intervention. The sediment size, deposition rate and human activities have positive relationship with the contents of heavy metals which directly impact the pollution level of heavy metals in sediments in Shenzhen Bay. 展开更多
关键词 surface sediments core sediments distribution characteristics pollution assessments Shenzhen Bay in Guangdong Province
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Distribution Characteristics and Accumulation Model for the Coal-formed Gas Generated from Permo-Carboniferous Coal Measures in Bohai Bay Basin, China: A Review 被引量:4
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作者 JIANG Youlu HU Hongjin +1 位作者 Jon GLUYAS ZHAO Kai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第6期1869-1884,共16页
Coal-formed gas generated from the Permo-Carboniferous coal measures has become one of the most important targets for deep hydrocarbon exploration in the Bohai Bay Basin,offshore eastern China.However,the proven gas r... Coal-formed gas generated from the Permo-Carboniferous coal measures has become one of the most important targets for deep hydrocarbon exploration in the Bohai Bay Basin,offshore eastern China.However,the proven gas reserves from this source rock remain low to date,and the distribution characteristics and accumulation model for the coal-formed gas are not clear.Here we review the coal-formed gas deposits formed from the Permo-Carboniferous coal measures in the Bohai Bay Basin.The accumulations are scattered,and dominated by middle-small sized gas fields,of which the proven reserves ranging from 0.002 to 149.4×108 m3 with an average of 44.30×108 m3 and a mid-point of 8.16×108 m3.The commercially valuable gas fields are mainly found in the central and southern parts of the basin.Vertically,the coal-formed gas is accumulated at multiple stratigraphic levels from Paleogene to Archaeozoic,among which the Paleogene and PermoCarboniferous are the main reservoir strata.According to the transporting pathway,filling mechanism and the relationship between source rocks and reservoir,the coal-formed gas accumulation model can be defined into three types:"Upward migrated,fault transported gas"accumulation model,"Laterally migrated,sandbody transported gas"accumulation model,and"Downward migrated,sub-source,fracture transported gas"accumulation model.Source rock distribution,thermal evolution and hydrocarbon generation capacity are the fundamental controlling factors for the macro distribution and enrichment of the coal-formed gas.The fault activity and the configuration of fault and caprock control the vertical enrichment pattern. 展开更多
关键词 distribution characteristics of natural gas accumulation model coal-formed gas Permo-Carboniferous coal measures Bohai Bay Basin
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Porosity Distribution Characteristics and Geological Analysis of Brine Storage Medium in the Qaidam Basin, Western China 被引量:2
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作者 HU Shuya XIAO Changlai +4 位作者 LIANG Xiujuan ZHAO Quansheng WANG Guangcai ZHANG Jianwei FENG Juan 《Chinese Geographical Science》 SCIE CSCD 2018年第4期707-716,共10页
Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. P... Underground brine is an unusual water resource that contains abundant mineral resources. It is distributed widely in the Qaidam Basin, western China, a hyperarid inland basin located in the northern Tibetan Plateau. Pores in the brine storage medium act as storage space and transmission channels of underground brine. Therefore, the porosity of brine storage medium determines its ability to store brine. In this study, Mahai Salt Lake was used as the research area as a modern saline lake located in the north area of the Qaidam Basin. A total of 100 porosity samples were collected from eight sampling points in two profiles of the research area at sampling depths of 1.30–314.78 m. The porosity distribution characteristics and influencing factors in brine storage medium were analysed according to the measured porosity data. Based on analysis of the pore structure characteristics, the brine storage medium contains intercrystalline pores, unlike conventional freshwater storage mediums. Moreover, the primary salt rock is susceptible to dissolution by lighter brine, facilitating the formation of secondary porosity. Due to the formation of secondary pores, a porosity greater than 20% remains even at buried depths greater than 100 m. Based on the geological statistical analysis, due to the geographic location, salt formation time, and depositional environment, the porosity values of Mahai Salt Lake do not exhibit a wider distribution, but also show more extreme values than a nearby salt lake. Based on the porosity characteristics by depth, due to the presence of secondary pores, flooding, stratigraphic static pressure, and other factors, porosity shows fluctuations with increasing depth. 展开更多
关键词 POROSITY brine storage medium distribution characteristics geological analysis salt lakes in Qaidam Basin
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Temporal distribution characteristics of GNSS ionospheric occultation data and its effects in earthquake-ionosphere anomaly detection 被引量:2
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作者 Zhao Ying An Jiachun 《Geodesy and Geodynamics》 2013年第4期33-40,共8页
The temporal distribution characteristics of COSMIC occultation data are analyzed in detail, and the limitations in earthquake-ionosphere anomaly detection caused by the temporal distribution characteristics of COSMIC... The temporal distribution characteristics of COSMIC occultation data are analyzed in detail, and the limitations in earthquake-ionosphere anomaly detection caused by the temporal distribution characteristics of COSMIC occultation data are discussed using the example of the Wenchuan earthquake. The results demonstrate that there is no fixed temporal resolution for COSMIC occultation data when compared with other ionospheric observation techniques. Therefore, occultation data cannot currently be independently utilized in research studies but can only be used as a complement to other ionospheric observation techniques for applications with high temporal resolution demands, such as earthquake-ionosphere anomaly detection. 展开更多
关键词 CNSS radio occultation IONOSPHERE temporal distribution characteristics EARTHQUAKE
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Research on Correlation between TCM Syndrome Distribution Characteristics and Prognosis of Hypertensive Intracerebral Hemorrhage Operation 被引量:2
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作者 Gang Yang Jianju Feng +6 位作者 Shaojun Yang Junjie Lv Donghai Yuan Chenbing Wang Feng Ding Chao Gu Gaofeng Shao 《Journal of Biosciences and Medicines》 2021年第4期138-144,共7页
<strong>Objective: </strong>This study is to analyze correlation between traditional Chinese medicine (TCM) syndrome distribution characteristics and prognosis of hypertensive intracerebral hemorrhage (HIC... <strong>Objective: </strong>This study is to analyze correlation between traditional Chinese medicine (TCM) syndrome distribution characteristics and prognosis of hypertensive intracerebral hemorrhage (HICH) operation. <strong>Methods: </strong>In this study, a total of 150 patients who had received HICH operation from April, 2017 to December, 2020 in our hospital and conformed to inclusion standards were selected. According to classification of TCM syndromes, amount of bleeding of patients was recorded through multiple radiological technologies, baseline information was collected, and prognosis was investigated. The final event was long-term follow-up visit of all-cause mortalities. Moreover, correlation between prognosis and TCM syndromes was analyzed. <strong>Results:</strong> It found through investigations that there are no statistically significant differences in composition ratio of TCM syndromes among patients with different genders and different age ranges (P > 0.05). Among so many TCM syndromes, bleeding amount of patients with declining vitality and distraction is the highest, while bleeding amount of patients with stirring wind due to yin deficiency is the lowest. With respect NIHSS scores, the patients with declining vitality and distraction show the highest NIHSS scores at admission and 10 d of the course of the disease, followed by patients with upward disturbance of wind-fire. There are statistically significant differences among these two groups (P < 0.05). In this study, follow-up visits are performed to all 150 patients and the average follow-up visit time ranges within 2 - 15 months. A total of 13 deaths are reported. Number of all-cause deaths has statistically significant differences among different syndromes (P < 0.05). <strong>Conclusions:</strong> Evolutionary characteristics of TCM syndromes of HICH are manifested by development from evidence-based symptoms to deficiency syndromes. Different syndromes are correlated with prognosis of patients. On the one hand, this can be used as an objective index for TCM syndrome classification. On the other hand, this is conducive to judge prognosis recovery of patients and to apply the corresponding symptomatic treatment. 展开更多
关键词 HICH TCM Syndromes distribution characteristics PROGNOSIS CORRELATION
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Spatial distribution characteristics and main controlling factors of germanium in soil of northern Dabie Mountains, China 被引量:1
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作者 Qiu-yao Dong Jiao Xiang +3 位作者 Chao Song Pan Wang Hao-tian Wen Ming-jiang Yan 《Journal of Groundwater Science and Engineering》 2022年第4期381-392,共12页
With the increasing application of germanium(Ge)elements in modern industry,military and medical health industries,especially with the growing demand for Ge-rich agricultural products,the study of Ge-rich soil has bec... With the increasing application of germanium(Ge)elements in modern industry,military and medical health industries,especially with the growing demand for Ge-rich agricultural products,the study of Ge-rich soil has become particularly important,but the enrichment pattern and control factors of Ge-rich soil are still not well understood due to the high dispersion and high migration of Ge-rich soil.In this paper,495 surface soil(0-20 cm)and 149 deep soil(150-200 cm)samples were collected from the northern foothills of Dabie Mountain using a double-layer grid layout,and the spatial distribution and enrichment characteristics of Ge were studied by high-resolution method,and the controlling factors affecting the distribution of Ge-rich soil was analyzed by geo-statistics and spatial analogy.The results show an average Ge content of 1.34 mg/kg for the surface and 1.36 mg/kg for the deep soil.In the assessment grade classification of surface and deep soil for Ge,the abundant and sub-abundant grades account for 37.97%and 31.70%,respectively,covering 752 km2 and 634 km2.Surface Ge-rich regions are distributed in concentrated strips in the north-central part of the studied region,and there is no clear pattern in the spatial distribution of deep soils.In the areas under study,such as Fenlukou,Dingji,and Jiangjiadian,the surface soil is very rich in Ge and has a high enrichment factor,which is valuable for agricultural development.In surface soils,river deposits and shallow metamorphic rock parent materials have the highest content of Ge,while in deep soils,the highest content has been found in the parent material of moderately acidic rock.Both surface and deep soils have the highest Ge content in purple paddy soils and plain areas.The source of Ge in the soils of the study area is most influenced by the lithology of the soil-forming parent material,while the distribution of Ge in the surface soils is jointly influenced by pH,SiO_(2),TFe_(2)O_(3),and Al_(2)O_(3) in the soil.This study has implications for understanding the enrichment pattern of Ge in soil and its controlling factors as well as for the development of Ge-rich agricultural products. 展开更多
关键词 GERMANIUM SOIL Enrichment feature distribution characteristics Influencing factors
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Distribution characteristics and source of BTEX in groundwater in Guangzhou,Guangdong Province,P.R.China 被引量:1
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作者 LIU Chun-yan SUN Ji-chao +2 位作者 JING Ji-hong ZHANG Ying GUO Wei-xuan 《Journal of Groundwater Science and Engineering》 2016年第3期238-246,共9页
In order to find out the distribution characteristics of BTEX in groundwater, which include Benzene, Toluene, Ethylbenzene, p-Xylene, m-Xylene, and o-Xylene, 82 groups of groundwater samples and 10 surface water sampl... In order to find out the distribution characteristics of BTEX in groundwater, which include Benzene, Toluene, Ethylbenzene, p-Xylene, m-Xylene, and o-Xylene, 82 groups of groundwater samples and 10 surface water samples collected from Guangzhou in Guangdong during 2005 to 2008 were tested by gas chromatography and mass spectrum(GC/MS). The result showed that the BTEX concentration in groundwater does not exceed the standard. The detection rate of BTEX is 14.63% in groundwater, and the total BTEX concentration is lower than 9.5 μg/L. Of 6 kinds of BTEX, toluene had the highest detection rate(12.20%) and detection value(9.5 μg/L), which was followed by Benzene, with the detection rate of 3.65%, and detection value of 4.9 μg/L respectively; most of samples with BTEX are distributed in Huangpu district, Baiyun district, Huadu district and other industrialized areas; this spatial distribution and urban distribution have obvious consistency. With economic development, plant expansion and population growth led to a large amount of waste water discharge, and infrastructure construction is lagging behind, indicating that rapid urbanization is a major driving force of BTEX in groundwater, and through the analysis of a typical area, it is found that benzene system surface water infiltration was an important source of BTEX in groundwater of Guangzhou. 展开更多
关键词 GUANGZHOU GROUNDWATER BTEX distribution characteristics Source to investigate
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Distribution Characteristics of Spermophilus dauricus in Manchuria City in China in 2015 through ‘3S' Technology 被引量:1
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作者 FAN Long Xing WU En Qi +3 位作者 QU Xiao Chen LIU Chao NING Bao An LIU Ying 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第8期603-608,共6页
Plague is a virulent infectious disease in China. In this study, '3S' technology was used to perform spatial autocorrelation analysis and spatial interpolation analysis for Spermophilus dauricus (S. Dauricus, a spe... Plague is a virulent infectious disease in China. In this study, '3S' technology was used to perform spatial autocorrelation analysis and spatial interpolation analysis for Spermophilus dauricus (S. Dauricus, a species of ground squirrel) captured in Manchuria City in 2015. The results were visually inspected. During the two-month (May to July) plague surveillance in 2015, 198 S. 展开更多
关键词 TECHNOLOGY distribution characteristics of Spermophilus dauricus in Manchuria City in China in 2015 through
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