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"Endogenous wind " Theory theory in the prevention and treatment of anti-tumor treatment-related adverse reaction related research progress
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作者 Huan-Huan Wen Hui-Yuan Wu +5 位作者 Yan-Fei Yi Lu Xiao Zi-Yang Li Xi-Ya Yuan Yang Liu Zi-Yan Huang 《Cancer Advances》 2021年第6期14-18,共5页
The treatment of malignant tumor is mainly based on modern medical treatment,after treatment,there are many adverse reactions,such as dizziness,headache,fever,numbness of limbs,pruritus,rash,spasm,phalacrosis,elevated... The treatment of malignant tumor is mainly based on modern medical treatment,after treatment,there are many adverse reactions,such as dizziness,headache,fever,numbness of limbs,pruritus,rash,spasm,phalacrosis,elevated blood pressure,anemia,myelosuppression,impaired functions of liver and kidney."Endogenous wind"is a part of Traditional Chinese medicine,and the researches are mainly focused on tumor metastasis and treatment.The researches on the adverse reactions associated with the treatment of malignant tumors are less.This paper is built on the theory of"endogenous wind"of Chinese medicine,and initially analyzes the progress of the research on adverse reactions of malignant tumors after treatment by modern medical means. 展开更多
关键词 “Endogenous wind”theory malignant tumor adverse reactions research progress
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Analysis on Status and Development Trend of Wind Erosion in Black Earth Region of Northeast China 被引量:2
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作者 刘铁军 珊丹 +2 位作者 郭建英 高天明 赵显波 《Agricultural Science & Technology》 CAS 2011年第12期1925-1928,共4页
In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In a... In this paper,areas and main factors of wind erosion in black earth region of Northeast China were systematically analyzed,as well as the development trend of wind erosion in black earth region of Northeast China.In addition,development trend of wind erosion in black earth region of Northeast China was analyzed from the aspects of the geographic position,climatic change law in recent 40 years and effects of northeast sand land desertification on wind erosion in black earth region,which had provided references for the research and prevention of wind erosion in soil of black earth region of Northeast China. 展开更多
关键词 Black earth region of Northeast China wind erosion Water loss and soil erosion wind erosion factors
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Wind speed change regionalization in China(1961-2012) 被引量:12
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作者 SHI Pei-Jun ZHANG Gang-Feng +1 位作者 KONG Feng YE Qian 《Advances in Climate Change Research》 SCIE CSCD 2015年第2期151-158,共8页
This research quantitatively recognized the wind speed change using wind speed trend and trend of wind speed variability from 1961 to 2012 and regionalized the wind speed change on a county-level basis.The mean wind s... This research quantitatively recognized the wind speed change using wind speed trend and trend of wind speed variability from 1961 to 2012 and regionalized the wind speed change on a county-level basis.The mean wind speed observation data and linear fitting method were used.The findings suggested that level-I regionalization includes six zones according to wind speed trend value in different regions,viz.Northeast ChinaeNorth China substantial declining zone,EasteCentral China declining zone,Southeast China slightly declining zone,Southwest China very slightly declining zone,Northwest China declining zone,and QinghaieTibetan Plateau slightly declining zone.Level-II regionalization divides China into twelve regions based on trend of wind speed variability and the level-I regionalization results. 展开更多
关键词 wind SPEED TREND regionALIZATION wind SPEED variab
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Projections of Wind Changes for 21st Century in China by Three Regional Climate Models 被引量:13
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作者 JIANG Ying Luo Yong +3 位作者 ZHAO Zongci SHI Ying XU Yinlong ZHU Jinhong 《Chinese Geographical Science》 SCIE CSCD 2010年第3期226-235,共10页
This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studi... This paper examines the capability of three regional climate models (RCMs), i.e., RegCM3 (the International Centre for Theoretical Physics Regional Climate Model), PRECIS (Providing Regional Climates for Impacts Studies) and CMM5 (the fifth-generation Pennsylvania State University-the National Center for Atmospheric Research of USA, NCAR Mesoscale Model) to simulate the near-surface-layer winds (10 m above surface) all over China in the late 20th century. Results suggest that like global climate models (GCMs), these RCMs have the certain capability of imitating the distribution of mean wind speed and fail to simulate the greatly weakening wind trends for the past 50 years in the country. However, RCMs especially RegCM3 have the better capability than that of GCMs to simulate the distribution and change feature of mean wind speed. In view of their merits, these RCMs were used to project the variability of near-surface-layer winds over China for the 21st century. The results show that 1) summer mean wind speed for 2020-2029 will be lower compared to those in 1990-1999 in most area of China; 2) annual and winter mean wind speed for 2081-2100 will be lower than those of 1971-1990 in the whole China; and 3) the changes of summer mean wind speed for 2081-2100 are uncertain. As a result, although climate models are absolutely necessary for projecting climate change to come, there are great uncertainties in projections, especially for wind speed, and these issues need to be further explored. 展开更多
关键词 wind speed PROJECTION regional climate model global climate model
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Discussion on the Assessment Method of Wind Energy Resources by Using Regional Meteorological Data 被引量:4
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作者 HE Jie-yan DAI Yu +3 位作者 JIN Xuan-xi LV Xiao-hua WANG Wei-nong LIU Cong-sheng 《Meteorological and Environmental Research》 CAS 2011年第2期10-12,17,共4页
The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resource... The exploitation status of wind energy resources was analyzed, and the distribution of wind energy resources and regional meteorological stations were introduced, and then the assessment method of wind energy resources by using data from regional meteorological station was studied taking Huangjin Regional Meteorological Station in Xinning County in Hunan Province for example, besides, corresponding software was compiled. By means of SQL database and program, the method was used simply and easily and had positive meaning for the development of wind energy resources and excavation of wind farm in inland region. 展开更多
关键词 regional meteorological station wind energy resources Assessment method China
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Numerical simulation of superhalo electrons generated by magnetic reconnection in the solar wind source region 被引量:2
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作者 Li-Ping Yang Ling-Hua Wang +4 位作者 Jian-Sen He Chuan-Yi Tu Shao-Hua Zhang Lei Zhang Xue-Shang Feng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第3期348-362,共15页
Superhalo electrons appear to be continuously present in the interplane- tary medium, even during very quiet times, with a power-law spectrum at energies above ~2 keV. Here we numerically investigate the generation o... Superhalo electrons appear to be continuously present in the interplane- tary medium, even during very quiet times, with a power-law spectrum at energies above ~2 keV. Here we numerically investigate the generation of superhalo electrons by magnetic reconnection in the solar wind source region, using magnetohydrody- namics and test particle simulations for both single X-line reconnection and multiple X-line reconnection. We find that the direct current electric field, produced in the mag- netic reconnection region, can accelerate electrons from an initial thermal energy of T ~105 K up to hundreds of keV. After acceleration, some of the accelerated elec- trons, together with the nascent solar wind flow driven by the reconnection, propagate upwards along the newly-opened magnetic field lines into interplanetary space, while the rest move downwards into the lower atmosphere. Similar to the observed superhalo electrons at 1 AU, the flux of upward-traveling accelerated electrons versus energy dis- plays a power-law distribution at ~ 2-100 keV, f(E)~ E^-δ, with a 6 of ~1.5 - 2.4. For single (multiple) X-line reconnection, the spectrum becomes harder (softer) as the anomalous resistivity parameter a (uniform resistivity η) increases. These modeling results suggest that the acceleration in the solar wind source region may contribute to superhalo electrons. 展开更多
关键词 acceleration of particles -- methods:numerical -- Sun:particle emission-- (Sun:) solar wind -- Sun: transition region
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Relationship Between Watershed Landscape Pattern Change and Runoff-Sediment in Wind-Water Erosion Crisscross Region 被引量:2
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作者 WANG Jinhua ZHANG Ronggang +2 位作者 JIN Lijun YAO Wenyi LI Zhanbin 《Journal of Landscape Research》 2017年第5期53-58,共6页
This paper selected the typical wind-water erosion crisscross region Xiliugou watershed for research to reveal the impact of the landscape pattern change of the underlying surface in wind-water erosion crisscross regi... This paper selected the typical wind-water erosion crisscross region Xiliugou watershed for research to reveal the impact of the landscape pattern change of the underlying surface in wind-water erosion crisscross region where soil erosion is most serious on rainfall and runoff as well as erosion and sediment.Based on the Landsat TM image data and measured data of runoff-sediment in that watershed,the paper analyzed the characteristics of watershed landscape pattern change and runoff-sediment and explored the relationship between landscape index and runoff-sediment yield by means of GIS and Fragstats.The results were included as follows.(1)Grassland was the dominant landscape.In terms of the number of patches and area change rate,from 1985 to 2010,cultivated land,forest land and construction land were most stable,followed by unused land.Unused land,grassland and cultivated land experienced the most dramatic conversion and maximally affected by human activities.(2)The inter-annual difference between annual runoff and annual sediment load was significant.Compared with the annual sediment load,the trend of decreasing runoff was more obvious.The correlation coefficient of runoff-sediment was 0.67,representing a significant correlation.(3)There was a significant correlation between the landscape index and runoff-sediment.The runoff was negatively correlated with the largest patch index,patch cohesion index,aggregation index and contagion index,but positively correlated with landscape morphology index and landscape division index.And the sediment was negatively correlated with the contagion index,aggregation index and plaque cohesion index,but positively correlated with other landscape indexes.The results indicate that with the increase of the largest patch index,patch cohesion index and aggregation index,the rainfall infiltration capacity increase obviously and the soil erosion reduce significantly.Therefore,increasing the largest patch index,patch cohesion and aggregation index of the watershed landscape can enhance the function of water storage and soil conservation as well as ecological optimization in the windwater erosion crisscross region.The results can provide theoretical support for the ecological environment construction and comprehensive utilization of water and soil resources. 展开更多
关键词 wind-water erosion crisscross region Landscape pattern RUNOFF SEDIMENT Xiliugou Watershed
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Changes of spring wind erosion based on wind erosion climate factor in the black soil region of Northeast China
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作者 YAN Ping JI Sheng-tai +5 位作者 LI Xiu-fen ZHU Hai-xia WANG Liang-liang ZHAI Mo WANG Ping ZHAO Hui-ying 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1712-1724,共13页
The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security ... The dry and windy climate and low ground cover in spring in the black soil region of Northeast China make the soil strongly affected by wind erosion,which seriously threatens the food security and ecological security of this region.In this paper,based on the daily observation data of 124 meteorological stations in study area from 1961 to 2020,seasonal and monthly wind erosion climate factor(C)in spring(March to May)were calculated by using the method proposed by the Food and Agriculture Organization of the United Nations(FAO),the wind erosion characterization in spring were systematically analyzed based on C by various statistical analysis methods.The results showed that in the past 60 years,spring wind erosion climate factor(CSp)and monthly C of the whole region and each province(region)all showed highly significant decreasing trend,but they began to show rebounded trend in the middle or late 2000s.CSp of the study area showed a significant upward trend since 2008 with an increase of 4.59(10a)^(-1).The main contributors to this upward trend are the changes of C in March and in April.For the four provinces(regions),CSp in Heilongjiang,Jilin,Liaoning and eastern Inner Mongolia all showed rebounded since 2008,2011,2008 and 2009,respectively.The rebounded trend of CSp in eastern Inner Mongolia was the most obvious with a tendency rate of 11.27(10a)^(-1),and its mutation occurred after 1984.The rebound trend of CSp in Heilongjiang Province takes the second place,with a trend rate of 4.72(10a)^(-1),but there’s no obvious time mutation characteristics.The spatial characteristics of CSpand monthly C are similar,showing decreasing characteristics centered on the typical black soil belt of Northeast China.Compared with 1961-1990,in the period from 1991 to 2020,the proportion of high value areas(CSp>35,monthly C>10)has decreased to varying degrees,while the proportion of low value areas(CSp≤10,monthly C≤4)has increased.The trends of seasonal and monthly C in 82.2%~87.7%of the stations show significant decreases at 95%confidence level.CSp is closely related to wind speed at 2m height,temperature difference,minimum temperature and precipitation in the same period,of which the correlation between CSp and wind speed is the strongest,indicating that the main control factor for CSp in the study area is wind speed,but the impact of the change of temperature and precipitation on CSp cannot be ignored. 展开更多
关键词 wind erosion climate erosivity Spatiotemporal 1characteristics Climate change Rebounded trend Typical black soil region Northeast China
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Landscape Visual Environment Impact Analysis of Wind Power Project in Plain Region--Case in One Wind Power Farm Project of Zhanjiang
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作者 Xiao Chaoming Liu Xucheng 《Meteorological and Environmental Research》 CAS 2016年第2期27-30,共4页
The construction of wind power project is conducive to saving energy,reducing emissions and regulating energy structure. But it inevitably causes some impacts on the environment in the construction process. Because th... The construction of wind power project is conducive to saving energy,reducing emissions and regulating energy structure. But it inevitably causes some impacts on the environment in the construction process. Because that the height of wind power generator generally exceeds 100 m,and visual range in plain region is farther,it is necessary to scientifically and rationally evaluate and analyze landscape visual environment impact of wind power generator in plain region. One wind power farm project of Zhanjiang is located in typical plain region of Guangdong coast. Referring to traditional analytic method of landscape visual impact and comparing with actual situation for the same kind of project in the region,results show that it is " extremely sensitive" area at 0- 2. 5 km from wind power generator, " very sensitive" area at 2. 5- 5. 0 km, " sensitive" area at 5- 10 km, "generally sensitive" area at 10- 20 km,and non-sensitive area outside 20 km. 展开更多
关键词 wind power project Plain region Landscape vision Environmental Impact Assessment China
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Assessment on Development of Wind Energy in Offshore Regions of Estonia
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作者 T. Tomson A. Kallis 《Journal of Energy and Power Engineering》 2011年第9期794-801,共8页
Up to now legislation of economical usage of Estonian sea shelf is lacking, what breaks development of wind farms. Therefore it is expedient to look the potential of wind resources and prablems to use it. In this pape... Up to now legislation of economical usage of Estonian sea shelf is lacking, what breaks development of wind farms. Therefore it is expedient to look the potential of wind resources and prablems to use it. In this paper the potential resource of four characteristic offshore regions in Estonia are assessed. Two different approaches have been used to assess the dynamic quality of the wind power, both of which lead to the same result. The dynamic quality of the load of the grid is also assessed since any consumer will be affected by the total influence of both these dynamic processes. These processes do limit the usage of wind power due to peculiarities of the Estonian electrical grid. 展开更多
关键词 Offshore regions dynamic quality wind power.
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Unlocking multidirectional and broadband wind energy harvesting with triboelectric nanogenerator and vortex-induced vibration of sphere
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作者 Lanbin ZHANG Yixiang HE +2 位作者 Bo MENG Huliang DAI Lin WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第11期1895-1912,共18页
A unique oscillating wind-driven triboelectric nanogenerator(OWTENG)based on the sphere's vortex-induced vibration(VIV)behavior is proposed in this study,which can harvest wind energy across a multitude of horizon... A unique oscillating wind-driven triboelectric nanogenerator(OWTENG)based on the sphere's vortex-induced vibration(VIV)behavior is proposed in this study,which can harvest wind energy across a multitude of horizontal directions.With the Euler-Lagrange method,the coupled governing equations of the OWTENG are established and subsequently validated by experimental tests.The vibrational properties and output performance of the OWTENG for varying wind speeds are analyzed,demonstrating its effectiveness in capturing wind energy across a broad range of wind speeds(from 2.20 m/s to 8.84 m/s),and the OWTENG achieves its peak output power of 106.3μW at a wind speed of 5.72 m/s.Furthermore,the OWTENG maintains a steady output power across various wind directions within the speed range of 2.20 m/s to 7.63 m/s.Nevertheless,when the wind speed exceeds 7.63 m/s,the vibrational characteristics of the sphere shift based on the wind direction,leading to fluctuations in the OWTENG's output power.This research presents an innovative approach for designing vibrational triboelectric nanogenerators,offering valuable insights into harvesting wind energy from diverse directions and speeds. 展开更多
关键词 wind energy harvesting triboelectric nanogenerator vortex-induced vibration(VIV) lock-in region
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Analysis of Short-term Heavy Precipitations in a Regional Heavy Rainstorm in Shannxi Province
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作者 王楠 《Agricultural Science & Technology》 CAS 2013年第3期411-416,共6页
[Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanx... [Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanxi Province in late July 2010 as an example, data of five Doppler weather radars in Shaanxi Province were employed for a detailed analysis of the evolution of the heavy rainstorm pro- cess. [Result] Besides the good large-scale weather background conditions, the de- velopment and evolution of some mesoscale and small-scale weather systems direct- ly led to short-term heavy precipitations during the heavy rainstorm process, involv- ing the intrusion of moderate IS-scale weak cold air and presence of small-scale wind shear, convergence and adverse wind area. In addition, small-scale convection echoes were arranged in lines and formed a "train effect", which would also con- tribute to the generation of short-term heavy precipitation. [Conclusion] This study provided basic information for more clear and in-depth analysis of the formation mechanism of short-term heavy precipitations. 展开更多
关键词 Short-term heavy precipitation Doppler weather radar adverse wind area: Train effect
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基于Region Manager的北京土壤可风蚀性研究 被引量:3
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作者 赵峰 韩煜 《水土保持研究》 CSCD 北大核心 2008年第6期24-27,共4页
在对北京市各种类型土壤进行调查的基础上,采用美国土壤学家D.W.Fryrear等人的计算土壤可蚀部分含量方程,计算北京主要土壤类型(亚类)表层的可蚀含量,建立了北京市可风蚀性数据库。用Region Manager地理信息系统制作北京土壤可风蚀性风... 在对北京市各种类型土壤进行调查的基础上,采用美国土壤学家D.W.Fryrear等人的计算土壤可蚀部分含量方程,计算北京主要土壤类型(亚类)表层的可蚀含量,建立了北京市可风蚀性数据库。用Region Manager地理信息系统制作北京土壤可风蚀性风分级图,并对北京地区主要土壤类型的可风蚀性进行分析与讨论,为正确评价北京土壤风蚀危害提供科学依据。 展开更多
关键词 北京 风蚀 土壤类型 分级图
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A review of the research on complex erosion by wind and water 被引量:3
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作者 SONG Yang YAN Ping LIU Lianyou 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期231-241,共11页
Complex erosion by wind and water, which is also called aeolian-fluvial interactions, is an important erosion process and landscape in arid and semiarid regions. The effectiveness of links between wind and water proce... Complex erosion by wind and water, which is also called aeolian-fluvial interactions, is an important erosion process and landscape in arid and semiarid regions. The effectiveness of links between wind and water process, spatial environmental transitions and temporal environmental change are the three main driving forces determining the geomorphologic significance of aeolian-fluvial interactions. As a complex interrelating and intercoupling system, complex erosion by wind and water has spatial- temporal variation features. The process of complex erosion by wind and water can be divided into palaeoenvironmental process and contemporary process. Early work in drylands has often been attributed to one of two schools advocating either an 'aeolianist' or a 'fluvialist' perspective, so it was not until the 1930s that the research on complex erosion by wind and water had been conducted. There are two obstacles restricting the research of complex erosion by wind and water. Firstly, how to transform in different temporal and spatial scales is still unsettled; and secondly, the research methodology is still immature. In the future, the mechanism and control of erosion, the complex soil erodibility in wind and water erosion will be the focus of research on complex erosion by wind and water. 展开更多
关键词 complex erosion by wind and water aeolian-fluvial interactions semiarid regions sediment contemporary process
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Numerical Simulation of Icing on Nrel 5-MW Reference Offshore Wind Turbine Blades Under Different Icing Conditions 被引量:3
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作者 CAO Hui-qing BAI Xu +2 位作者 MA Xian-dong YIN Qun YANG Xiang-yu 《China Ocean Engineering》 SCIE EI CSCD 2022年第5期767-780,共14页
Offshore wind energy resources are operational in cold regions,while offshore wind turbines will face the threat of icing.Therefore,it is necessary to study icing of offshore wind turbines under different icing condit... Offshore wind energy resources are operational in cold regions,while offshore wind turbines will face the threat of icing.Therefore,it is necessary to study icing of offshore wind turbines under different icing conditions.In this study,icing sensitivity of offshore wind turbine blades are performed using a combination of FLUENT and FENSAP-ICE software,and the effects of liquid water content(LWC),medium volume diameter(MVD),wind speed and air temperature on blade icing shape are analyzed by two types of ice,namely rime ice and glaze ice.The results show that the increase of LWC and MVD will increase the amount of ice that forms on the blade surface for either glaze ice or rime ice,and an increase of MVD will expand the adhesion surface between ice and blade.Before reaching the rated wind speed of 11.4 m/s,it does not directly affect the icing shape.However,after reaching the rated wind speed,the attack angle of the incoming flow decreases obviously,and the amount of ice increases markedly.When the ambient air temperature meets the icing conditions of glaze ice(i.e.,−5℃ to 0℃),the lower the temperature,the more glaze ice freezes,whereas air temperature has no impact on the icing of rime ice.Compared with onshore wind turbines,offshore wind turbines might face extreme meteorological conditions,and the wind speed has no impact on the amount of ice that forms on the blade surface for most wind speeds. 展开更多
关键词 environmental parameters cold regions offshore wind turbine RIME GLAZE numerical simulation
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A field investigation of wind erosion in the farming–pastoral ecotone of northern China using a portable wind tunnel: a case study in Yanchi County 被引量:1
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作者 nan ling dong zhibao +5 位作者 xiao weiqiang li chao xiao nan song shaopeng xiao fengjun du lingtong 《Journal of Arid Land》 SCIE CSCD 2018年第1期27-38,共12页
The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we co... The farming-pastoral ecotone in northern China is an extremely fr@e ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we conducted field simulated wind erosion experiments combined with laboratory analysis to investigate wind erosion of soils in trampled rangeland, non-tilled cropland and tilled cropland in Yanchi County, China. The results showed that compared with rangeland, the cropland had a higher soil water holding capacity and lower soil bulk density. The wind erosion rate of trampled rangeland was much higher than those of non-tilled cropland and tilled cropland. For cropland, the wind erosion rate of the soil after tilling was surprisingly less than that of the soil before tilling. With increasing of wind speed, the volume mean diameter of the eroded sediment collected by the trough in the wind tunnel generally increased while the clay and silt content decreased for all soils. The temporal variation in wind erosion of the trampled rangeland indicated that particle entrainment and dust emission decreased exponentially with erosion time through the successive wind erosion events due to the exhaustion of erodible particles. 展开更多
关键词 wind erosion rate wind tunnel eroded sediment soil particle size CROPLAND RANGELAND semi-arid region
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Relationship analysis between September precipitation in western China and 700 hPa wind field in East Asia 被引量:1
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作者 ShaoYong Chen Quan Xia +1 位作者 JunTin Guo Shu Lin 《Research in Cold and Arid Regions》 2011年第5期419-425,共7页
The regional wind index influencing September precipitation in western China has been defined using the 700 hPa u and v components of NCAR/NCEP reanalysis data of 1961 to 2006. There are three regional wind field indi... The regional wind index influencing September precipitation in western China has been defined using the 700 hPa u and v components of NCAR/NCEP reanalysis data of 1961 to 2006. There are three regional wind field indices: southwest, southeast, and north, and these indices reflect the change of East Asian monsoon. The relationship between the indices was studied, and results show that they not only have a close relationship, but also have independence. Moreover, there is an obvious relationship between the wind indices and the autumn in particular the September precipitation in western China. The effect of wind indices on rain occurrence is most different: the influenced area of the southwest wind index is larger than that of the southeast wind index, and the southwest wind index is a controlling factor on autumn precipitation in western China. The weakening of southwest wind is the main cause resulting in reduction of autumn precipitation on the east side of the Tibetan Plateau. 展开更多
关键词 western China September precipitation 700 hPa wind field regional wind index
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The Emission Heights of Transition Region Lines in an Equatorial Coronal Hole and the Surrounding Quiet Sun 被引量:1
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作者 Hui Tian Li-Dong Xia +2 位作者 Jian-Sen He Bo Tan Shuo Yao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第6期732-742,共11页
Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the... Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the surrounding quiet Sun region. We found that for all of the six lower-transition-region lines, the emission height is about 4-5 Mm in the equatorial coronal hole, and around 2 Mm in the quiet Sun region. This result confirms the previous findings that plasma with different temperature can coexist at the same layer of transition region. In the quiet Sun region, the emission height of the upper-transition-region line Ne VIII is almost the same that of the lower-transition-region line, but in the coronal hole, it is twice as high. This difference reveals that the outflow of Ne VIII is a signature of solar wind in the coronal hole and is just a mass supply to the large loops in the quiet Sun. 展开更多
关键词 Sun: transition region Sun: magnetic fields Sun: solar wind Sun: UV radiation
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Distribution of charged lunar dust in the south polar region of the moon 被引量:1
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作者 Qing Xia Ming-Hui Cai +3 位作者 Liang-Liang Xu Rui-Long Han Tao Yang Jian-Wei Han 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期441-448,共8页
Lunar dust is one of the most threatening problems confronting the return of human beings to the moon.In this work we studied the spatial distribution behavior of charged lunar dust in the solar wind plasma environmen... Lunar dust is one of the most threatening problems confronting the return of human beings to the moon.In this work we studied the spatial distribution behavior of charged lunar dust in the solar wind plasma environment in the south polar region of the moon and considered the influence of a mini-crater using Spacecraft Plasma Interactions Software.The distribution of dust and plasma at low solar altitude angles of 20°and 0°was studied,and the spatial density of lunar dust was~10^(10.4)m^(-3)and~10^(11.5)m^(-3),respectively.This is because a higher surface potential will result in transportation of small dust particles and photoelectrons can also neutralize positively charged lunar dust.The dust density in the plasma void region created by a mini-crater with a 5 m high wall was studied.We obtained a quasi-neutral electric environment in the plasma void region of the mini-crater,and the dust density was about a magnitude lower than that in other regions.The dust risk to a spacesuit is much lower on the nightside than on the dayside,but there is severe charged lunar dust transport in the region between light and shade,which is dominated by the difference in surface and plasma potential caused by photoelectrons. 展开更多
关键词 lunar dust south polar region solar wind mini-crater
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Quasi-periodic outflows observed by the X-Ray Telescope onboard Hinode in the boundary of an active region 被引量:2
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作者 Li-Jia Guo Hui Tian Jian-Sen He 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2010年第12期1307-1314,共8页
Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly und... Persistent outflows have recently been detected at the boundaries of some active regions. Although these outflows are suggested to be possible sources of the slow solar wind, the nature of these outflows is poorly understood. Through an analy- sis of an image sequence obtained by the X-Ray Telescope onboard the Hinode spacecraft, we found that quasi-periodic outflows are present in the boundary of an active region. The flows are observed to occur intermittently, often with a period of 5-10 min. The proj ected flow speed can reach more than 200 km s^-1, while its distribution peaks around 50 km s^-1. This sporadic high-speed outflow may play an important role in the mass loading process of the slow solar wind. Our results may imply that the outflow of the slow solar wind in the boundary of the active region is intermittent and quasiperiodic in nature. 展开更多
关键词 solar wind -- Sun: UV radiation -- active region
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