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Distributing Characteristics of the Charge on the Bomb Body with Capacitance Fuze
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作者 邓甲昊 詹毅 施聚生 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期291-295,共5页
For establishing the equation of the capacitive target detection accurately, the distributing characteristics of the charges on the bomb body with capacitance fuze were explored. Continuous charges were analyzed disp... For establishing the equation of the capacitive target detection accurately, the distributing characteristics of the charges on the bomb body with capacitance fuze were explored. Continuous charges were analyzed dispersively. Based on the Coulomb's law, the dynamic equilibrium equations of the inducing charges on the bomb body were set up. For the four cases of d 0/L (the ratio between the electrode distance and the bomb length), the curves of the charge's distribution were given. It was concluded that: ① the charge density decreases steadily from the end near the frontal electrode to the bomb tail; ② the declining rate of the density is governed by d 0/L , the larger the value of d 0/L ,the higher the declining rate, and vice versa. 展开更多
关键词 proximity fuze capacitance fuze target detection distribution characteristic of charge
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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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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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Quantitative Study on Characteristics of the Weibull Distribution 被引量:4
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作者 张铁岭 郑慕侨 张祖明 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期357-363,共7页
Aim To quantitatively study three characteristics of the Weibull distribution. Methods Theoritical analysis of the three characteristics of parameters of the Weibull distribution was done and mathematics software wa... Aim To quantitatively study three characteristics of the Weibull distribution. Methods Theoritical analysis of the three characteristics of parameters of the Weibull distribution was done and mathematics software was used to make some chart analysis. Results 17 equations and 7 figures were made. Conclusion Under the standard form, the class of the Weibull probable density founction(pdf) curves appear double peak shape. Under the standard form, the maximum value point curve of the Weibull pdf takes line t =0 and t=1 as asymptotes. When β = 3 30-3 40, the Weibull distribution is the most similar to the normal distribution. 展开更多
关键词 characteristics of Weibull distributions quasi zero points probable density founction(pdf)
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Experimental study on thermal characteristics of a double skin faade building 被引量:2
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作者 王芳 张小松 +1 位作者 谭俊杰 李秀伟 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期462-466,共5页
An experimental study of the thermal characteristics of an existing office building with double skin facade DSF were conducted in hot summer daytime in Nanjing China. The temperature distributions of the DSF and indoo... An experimental study of the thermal characteristics of an existing office building with double skin facade DSF were conducted in hot summer daytime in Nanjing China. The temperature distributions of the DSF and indoor environment were measured at different control modes of DSF.The results show that the energy consumption of the air conditioning system in room B with opened exterior vents a closed interior facade and an air cavity with shading was 21.0% less than that in room A with closed exterior vents a closed interior facade and air cavity without shading in 9.5 h. The temperature distributions of the DSF and indoor environment in both horizontal and vertical directions were decisively influenced by shading conditions. The usage of shading devices strengthens the stack effect on the air cavity. Compared to room A the temperature distribution in room B is more uniform with smaller fluctuations.Meanwhile the problem of overheating in the air cavity of the DSF is still present in all tested conditions. 展开更多
关键词 double skin facade THERMAL characteristics temperature distribution energy consumption
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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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Characteristics of loess landslides triggered by different factors in the Chinese Loess Plateau 被引量:6
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作者 MENG Zhen-jiang MA Peng-hui PENG Jian-bing 《Journal of Mountain Science》 SCIE CSCD 2021年第12期3218-3229,共12页
Loess landslides are one of the most serious geological disasters in the Chinese Loess Plateau.Research has revealed that earthquake,rainfall,and human activities are common triggers for loess landslides.In order to s... Loess landslides are one of the most serious geological disasters in the Chinese Loess Plateau.Research has revealed that earthquake,rainfall,and human activities are common triggers for loess landslides.In order to study the relationship and characteristics of these landslides triggered by different factors,the paper uses historic landslide data to expound the basic motion indices of landslides triggered by different factors.More than half of loess landslides occurred on concave surface slopes,while nearly 40%of the loess landslides occurred on convex surface slopes.Human activities have a great effect on the occurrence of landslides,and the distribution density of landslides on residential land was almost five times that of bare land.Additionally,earthquakeinduced loess landslides had the largest sliding volume,whereas the excavation-induced loess landslide had the smallest sliding volume.The sliding volume of irrigation-induced and rainfall-induced loess landslides were between earthquake-induced loess landslides and excavation-induced loess landslide.Many of loess landslides were induced by a combination of these factors,such as rainfall and excavation,irrigation and excavation.Then a model that described the impact of these factors on the loess landslides was proposed. 展开更多
关键词 Loess Plateau LANDSLIDES Multiple sliding Loess disaster chain Distribution characteristics
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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 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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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 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 controlling factors of typical antibiotics and antibiotic resistance genes in river networks in western area of Wangyu River,China 被引量:2
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作者 Jing-jing Zhang Juan Chen +3 位作者 Chao Wang Pei-fang Wang Han Gao Yu Hu 《Water Science and Engineering》 EI CAS CSCD 2022年第4期318-327,共10页
Antibiotics and antibiotic resistance genes(ARGs)pose health risks in aquatic environments because of their persistence and mobility.River networks can provide a perfect opportunity for exploring the occurrence and en... Antibiotics and antibiotic resistance genes(ARGs)pose health risks in aquatic environments because of their persistence and mobility.River networks can provide a perfect opportunity for exploring the occurrence and enrichment of ARGs and antibiotics in freshwater environments.On this basis,the abundances of four types of antibiotics(sulfonamides,quinolones,tetracyclines,and macrolides)and 13 ARGs(sulⅠ,sulⅡ,tetA,tetB,tetO,tetW,qnrA,qnrS,qnrD,ermB,ermF,ermC,and ere A)were measured in the river networks of the west bank of the Wangyu River in China.The spatial distribution and temporal variation of these antibiotics and ARGs were characterized,and their controlling factors were analyzed.All four types of antibiotics were detected with high frequencies between 41%and 100%.Quinolone antibiotics exhibited the highest average concentration(286.53 ng/L).The concentrations of quinolones,tetracyclines,and macrolides were significantly higher in the winter than in the summer,whereas the concentration of sulfonamides was higher in wet periods than in dry periods.Of the 13 ARGs,sulⅠwas the most abundant(1.28 x 10^(5)copies per milliliter),followed by sulⅡand tetO(5.41×10^(4)and 4.45×10^(4)copies per milliliter,respectively).The canonical correspondence analysis showed that environmental factors,including dissolved oxygen,water temperature,total nitrogen,pH,and total phosphorus,had significant effects on the abundance of ARGs.sulⅠ,sulⅡ,tetA,and tetB were significantly correlated with 16S ribosomal RNA sequences,indicating that the bacterioplankton community might affect the distribution of ARGs.The correlation heat map analysis showed that the spread of ARGs was influenced by specific bacterial groups,such as Acidobacteria and Cyanobacteria,indicating that these bacterioplankton may be the hosts of environmental ARGs. 展开更多
关键词 Wangyu river Antibiotic ARG Distribution characteristic Environmental factor River network
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Sediment distribution characteristics and environment evolution within 100 years in western Laizhou Bay,Bohai Sea,China 被引量:4
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作者 Mao-sheng Gao Guo-hua Hou +1 位作者 Xian-zhang Dang Xue-yong Huang 《China Geology》 2020年第3期445-454,共10页
This study is about the reconstruction of fluvial origins based on the grain size distribution of sediment deposits in the western Laizhou Bay,Bohai Sea,China.Thirteen sediment cores were selected to research sediment... This study is about the reconstruction of fluvial origins based on the grain size distribution of sediment deposits in the western Laizhou Bay,Bohai Sea,China.Thirteen sediment cores were selected to research sediment characteristics using the Sahu discriminant formula,C-M diagram,and Folk method.The results showed:(1)Bounded by the Guangli River estuary,the north sediment was affected by the water and sand flowing from the Yellow River during different periods.The south sediment came from multi-source rivers under the influence of the Xiaoqing River,Mihe River,and other coastal rivers;(2)the deposited sediments were dated by a clear historical record of the branched channel oscillation combined with the characteristics of the diversion channel,erosion,and regression.The subaqueous delta overlapped during several Yellow River channel runs(1897–1904,1929–1934,1938–1947,1947–1953,1976–1996)and the deposited sediment facies changed(the north tidal flat-abandoned subaqueous delta-lateral delta-delta front);(3)the deposited sediment characteristics can be revealed by studying the branched diversions of the Yellow River and coastal multi-rivers of the past one hundred years. 展开更多
关键词 SEDIMENT Grain size SILT Environment evolution Distribution characteristic Hydrogeological engineering Laizhou Bay Qingdao City China
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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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Distribution Characteristics of High Temperature Damage and Its Influence on the Rice Yield in the Area along Huaihe River 被引量:3
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作者 FENG De-hua1,JIANG Yue-lin1,YANG Tai-ming2,CHEN Jin-hua2 1.College of Resources & Environment,Anhui Agricultural University,Hefei 230036,China 2.Anhui Meteorological Science Research Institute,Hefei 230031,China 《Meteorological and Environmental Research》 CAS 2011年第3期73-76,80,共5页
[Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in... [Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in the area along Huaihe River during 1965-2009 and the yield data of Anhui single-season middle rice during 1967-2006 were selected.The occurrence characteristic of summer high temperature weather and the intensity of high temperature damage in the area along Huaihe River were analyzed.Based on the previous high temperature damage index of rice,Changfeng County where was the typical rice planting zone in the area along Huaihe River was as the representation,and the yield damage loss rate risk of high temperature damage in Changfeng was analyzed by combining with the historical yield data.[Result] The high temperature weather in the area along Huaihe River frequently happened.The high temperature damage presented 'N' shape trend from west to east.The occurrence frequency of high temperature weather in Huainan and Bengbu where were in the middle area along Huaihe River was more and was less in Huoqiu and Shouxian where were near the south mountain area of Anhui.The occurrence time mainly focused from the middle and last dekads of July to the first dekad of August after the plum rain.At this time,it was the booting,heading and flowering periods of single-season middle rice,and the influence on the rice yield was obvious.The damage loss rate of single-season middle rice yield in Changfeng County along Huaihe River continued to increase as the increasing of high temperature damage duration.But the occurrence probability decreased.The intensity grade of high temperature damage disaster loss rate which happened frequently concentrated mainly in levels I and II.The longer the high temperature damage duration in the reproductive growth stage of rice was,the bigger the damage loss rate was.But the corresponding occurrence probability was small,and vice versa.[Conclusion] The research provided the reference for assessing the high temperature disaster risk. 展开更多
关键词 High temperature damage Distribution characteristic RICE Disaster loss rate Area along Huaihe River China
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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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