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We Live on a Small Space Comet: The Third Extraordinary Motion of Earth towards the North Pole and Its Various Effects
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作者 Walid Nabil 《Advances in Aerospace Science and Technology》 2023年第3期21-33,共13页
The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibratio... The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibrations of traffic, and we listed successive scientific confirmations to indicate the rotation of the planet in a regular movement around its axis once every 24 hours, and it is running in another second movement around the sun once every 365¼ days, so are they only two movements, no more?! Is it possible for him to run at a regular speed in an additional direction? 展开更多
关键词 the Third Additional Regular Movement of the Planet Earth towards the north pole the Movement of the Planet Earth in Space the Spiral Path of the Earth the Speed of the Planet 1.3 Kilometers per Second the Planet Earth A Small Space Comet
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Aerial observations of sea ice and melt ponds near the North Pole during CHINARE2010 被引量:4
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作者 LI Lanyu KE Changqing +2 位作者 XIE Hongjie LEI Ruibo TAO Anqi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期64-72,共9页
An aerial photography has been used to provide validation data on sea ice near the North Pole where most polar orbiting satellites cannot cover. This kind of data can also be used as a supplement for missing data and ... An aerial photography has been used to provide validation data on sea ice near the North Pole where most polar orbiting satellites cannot cover. This kind of data can also be used as a supplement for missing data and for reducing the uncertainty of data interpolation. The aerial photos are analyzed near the North Pole collected during the Chinese national arctic research expedition in the summer of 2010(CHINARE2010). The result shows that the average fraction of open water increases from the ice camp at approximately 87°N to the North Pole, resulting in the decrease in the sea ice. The average sea ice concentration is only 62.0% for the two flights(16 and 19 August 2010). The average albedo(0.42) estimated from the area ratios among snow-covered ice,melt pond and water is slightly lower than the 0.49 of HOTRAX 2005. The data on 19 August 2010 shows that the albedo decreases from the ice camp at approximately 87°N to the North Pole, primarily due to the decrease in the fraction of snow-covered ice and the increase in fractions of melt-pond and open-water. The ice concentration from the aerial photos and AMSR-E(The Advanced Microwave Scanning Radiometer-Earth Observing System) images at 87.0°–87.5°N exhibits similar spatial patterns, although the AMSR-E concentration is approximately 18.0%(on average) higher than aerial photos. This can be attributed to the 6.25 km resolution of AMSR-E, which cannot separate melt ponds/submerged ice from ice and cannot detect the small leads between floes. Thus, the aerial photos would play an important role in providing high-resolution independent estimates of the ice concentration and the fraction of melt pond cover to validate and/or supplement space-borne remote sensing products near the North Pole. 展开更多
关键词 sea ice melt pond albedo concentration aerial observation north pole
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Interdecadal and decadal variation of temperature over North Pole area and the relation with solar activity 被引量:1
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作者 QU Weizheng ZHAO Jinping DU Ling HUANG Fei FAN Tingting 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2011年第2期53-61,共9页
Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere t... Obvious tendency and periodicity of the air temperature can be detected over the North Pole area.They are reflected as follows: a.the air temperature at the earth surface and in the middle layer of the stratosphere tends to be increased either in winter or in summer.The air temperature has increased 1.3 °C for about 50 years at a speed about 0.025 °C/year in January,and 0.013 °C/year in July.The air temperature in the middle layer of the stratosphere (10 hPa) in January has increased 10 °C.The temperature rising speed in July is 0.14 °C/year.Generally speaking,the temperature rising speed is quicker in winter than in summer and quicker in the upper layer than at the earth surface.b.The air temperature at the top layer of the troposphere (100 hPa) over the North Pole area tends to be increased either in winter or in summer.The air temperature in January has decreased 5.0 °C for about 50 years at a temperature decreasing speed about 0.094 °C/year,and at a temperature decreasing speed about 0.032 °C/year in July.The speed of the temperature decreasing is greater in winter than in summer.c.Periodicity.The air temperature respectively at different altitudes over the North Pole possesses interdecadal variation with a period of 22 years.In July the amplitude of the variation with a period of 22 years decreases rapidly from the high altitude to the low.This means that the 22–year’s period is more obvious at the high altitude than at the low altitude.At the earth surface layer in North Pole there also is obvious decadal variation with a period of 11 years.The analysis indicates that the 22-years’ period temperature variation is associated with the periodic variation of the solar magnetic field.The 11-year period temperature variation is corresponding to 11 year’ period of the variation of the sunspot number. 展开更多
关键词 decadal variation of air temperature solar activity north pole area
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Silver Swallow in the Air in North Pole——Successfully fly through North Pole of the China Eastern Airline
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《China's Foreign Trade》 2001年第7期26-27,共2页
关键词 Silver Swallow in the Air in north pole Successfully fly through north pole of the China Eastern Airline
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Expedition to Mars North Pole and Creation There a Scientific Research Base 被引量:1
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作者 Alexander Rubinraut 《Advances in Aerospace Science and Technology》 2020年第1期20-43,共24页
A project of the expedition to the north pole of Mars, which is carried out in two stages, has been developed. In the first stage, a space refueller and a mobile solar battery are delivered to the icy surface of the n... A project of the expedition to the north pole of Mars, which is carried out in two stages, has been developed. In the first stage, a space refueller and a mobile solar battery are delivered to the icy surface of the north pole of Mars. The delivery is carried out with the help of electric rocket ER-7, driven by the electric rocket engine “MARS”, and the source of electricity is a solar battery from gallium arsenide. In the second stage, the space train is formed from two interconnected ER-7 rockets and an orbital takeoff-landing capsule TLC-2, in which three astronauts land on the surface and carry out a complex of physical, biological and geological researches on Mars surface. The space refueller has been developed, which melts the water ice on the surface of Mars and with the help of an electrolyser and a liquefier produces fuel and oxidizer for the operation of the chemical rocket engine of the takeoff-landing capsule. To move astronauts from the north pole to the equator, a spacecraft—?marsoplane, which consists of the electric rocket ER-7 and the takeoff-landing capsule TLC-1 is developed. The duration of the expedition is 110 days at a cost of 2 billion dollars. 展开更多
关键词 MARS north pole Electrical Rocket ER-7 Takeoff-Landing Capsule TLC-1 and TLC-2 Space Refueller Marsoplane Superconducting Electrorocket Engine MARS
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Tibetans Studying In the North Pole
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《China's Tibet》 2002年第2期31-32,共2页
EDITOR'S NOTE: Longyearbyen, capital of the Svalbard Islands, entered its annualprolonged period of darkness on October9,2001.The sun was not due to rise againuntil March 8, 2002.During the five-month-long period ... EDITOR'S NOTE: Longyearbyen, capital of the Svalbard Islands, entered its annualprolonged period of darkness on October9,2001.The sun was not due to rise againuntil March 8, 2002.During the five-month-long period of perpetual night,people livingin the northernmost human settlement see only stars, snow and ice. In this part of theworld, however, there are four students from the Tibet Autonomous Regionjoint-venture school. 展开更多
关键词 In Tibetans Studying In the north pole
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Interannual Variations of Phytoplankton, Zooplankton and Chlorophyll a in the Arctic Seas and Their Relations to ENSO and AO 被引量:1
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作者 Zhang Haisheng Chen Jianfang +6 位作者 Han Zhengbing Ji Zhongqiang Xu Xudan Han Xibing Liu Zilin Peter, H.-U Vetter Walter 《Meteorological and Environmental Research》 CAS 2017年第2期37-48,53,共13页
To study effects of variations in climate-marine environment in the Arctic Ocean on ecology,based on the actual and reestablished data by biomarkers of algae in sediment in 1997,1999,2003,2008,and 2010,the interannual... To study effects of variations in climate-marine environment in the Arctic Ocean on ecology,based on the actual and reestablished data by biomarkers of algae in sediment in 1997,1999,2003,2008,and 2010,the interannual and spatial variations of phytoplankton,zooplankton and chlorophyll a concentration in the Chukchi Sea and the Bering Sea as well as their relations to El Nino-Southern Oscillation( ENSO) and Arctic Oscillation( AO) were analyzed. The results show that there were spatial and temporal anomalies in the phytoplankton community structure reestablished by biomarkers of algae in the Chukchi Sea and the Bering Sea in 1999 and 2010. The total content of biomarkers( brassicasterol,dinosterol,C37 alkenones and chlesterol) in sediment collected in 2010 was far lower than that in 1999,but brassicasterol was dominant in the two years,that is,diatom was dominant,which was consistent with the actual structure and distribution of phytoplankton community in 1999 and 2010; there were great changes in the dominant species of plankton in the two seas in 1999 and 2010,which could be regarded as the ecological response of the North Pole under the background of global warming. Chlorophyll a concentration in the water of the Bering Sea was 0. 720 μg/dm^3 at 0 m and 0. 765μg/dm^3 at 10 m in 1997 and 0. 723 μg/dm^3 at 0 m and 0. 731 μg/dm^3 at 10 m in 2003,and the concentration was very close to each other,which was affected by El Ni1 o and the negative phase of AO. It was 0. 395 μg/dm^3 at 0 m in 1999 and 0. 399 μg/dm^3 at 0 m and 0. 357 μg/dm^3 at 10 m in 2008,which was influenced by La Ni1 a and the positive phase of AO. The phases and intensity of AO and ENSO had various effects on the quantity and dominant species of phytoplankton and zooplankton in the Chukchi Sea and the Bering Sea. During the period of AO with positive or negative phase and El Ni1o( in 1997 and 2003),their combination was favorable to the growth of phytoplankton and zooplankton,while the combination of negative phase of AO and La Nina( in 2010) had adverse effects on the growth of phytoplankton. The combination of AO with positive phase and strong La Nina( in 1999 and 2008) had small effects on phytoplankton community. 展开更多
关键词 the north pole Sea area PHYTOPLANKTON ZOOPLANKTON CHLOROPHYLL a ENSO AO
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NUTRIENTS NEAR THE ARCTIC POLE REGION
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作者 沈志良 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1996年第4期303-307,共5页
The distributions of SiO<sub>3</sub>-Si, PO<sub>4</sub>-P, NO<sub>3</sub>-N and NO<sub>2</sub>-N concentrations in the seawater, iceand snow from 82°45′21″W, 88&#... The distributions of SiO<sub>3</sub>-Si, PO<sub>4</sub>-P, NO<sub>3</sub>-N and NO<sub>2</sub>-N concentrations in the seawater, iceand snow from 82°45′21″W, 88°01′20″N to the North Pole are reported and the exchange of thenutrients among the seawater, ice and snow are discussed. The average concentrations of the nutrients inthe seawater near the North Pole were 4.9±2.4μmol/L for SiO<sub>3</sub>-Si; 0.60±0.10μmol/L for PO<sub>4</sub>-P,3.4±1.7μmol/L for NO<sub>3</sub>-N and 0.13±0.04μmol/L for NO<sub>2</sub>-N. The nutrient concentrations inthe ice and snow in the North Pole were 0.20 and 0.65μmol/L for SiO<sub>3</sub>-Si; 0.22 and 0.25μmol/L forPO<sub>4</sub>-P; 1.6 and 5.8μmol/L for NO<sub>3</sub>-N, 0.19 and 0.15μmol/L for NO<sub>2</sub>-N. 展开更多
关键词 north pole NUTRIENTS
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Progress of International Meridian Circle Program
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作者 WANG Chi BLANC Michel +13 位作者 ZHANG Shunrong DENARDINI Clezio Marcos LIU William SHEN Xuhui WU Jian XU Jiyao LI Hui ZHANG Qinghe REN Liwen ZHU Yajun LI Guozhu DING Zonghua LIU Zhengkuan YANG Fang 《空间科学学报》 CAS CSCD 北大核心 2024年第4期741-745,共5页
In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the I... In 2024,the Chinese Meridian Project(CMP)completed its construction,deploying 282 instruments across 31 stations.This achievement not only provides a robust foundation but also serves as a reference template for the International Meridian Circle Program(IMCP).The IMCP aims to integrate and establish a comprehensive network of ground-based monitoring stations designed to track the propagation of space weather events from the Sun to Earth.Additionally,it monitors various disturbances generated within the Earth system that impact geospace.Over the past two years,significant progress has been made on the IMCP.In particular,the second phase of construction for the China-Brazil Joint Laboratory for Space Weather has been completed,and the North Pole and Southeast Asia networks are under active construction.The 2024 IMCP joint observation campaign was successfully conducted.To facilitate these developments,the scientific program committee of IMCP was established,following the success of 2023 IMCP workshop and the space weather school,which was co-hosted with the Asia-Pacific Space Cooperation Organization(APSCO)and sponsored by Chinese Academy of Sciences(CAS)and Scientific Committee on Solar-Terrestrial Physics(SCOSTEP).Preparations are now underway for the 2024 workshop in collaboration with the National Institute for Space Research(INPE)in Brazil. 展开更多
关键词 Chinese Meridian Project(CMP) International Meridian Circle Program(IMCP) China-Brazil Joint Laboratory for Space Weather north pole and Southeast Asia networks
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Artificial, Natural, Underlying Factors That Affect the Arctic Climate
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作者 Zhenzhou Weng 《Journal of Geoscience and Environment Protection》 2018年第11期101-108,共8页
In recent years, the Arctic climate has changed dramatically. This paper sums up the remarkable performance of climate change in the Arctic Circle by going deep into the Arctic Circle, collecting climate data and comp... In recent years, the Arctic climate has changed dramatically. This paper sums up the remarkable performance of climate change in the Arctic Circle by going deep into the Arctic Circle, collecting climate data and comparing it with previous years’ data and literature. The factors affecting climate change in the Arctic Circle are discussed from three aspects: artificial factors, natural factors and potential factors. The study finds out that the main factors that affect the Arctic climate are the large amount of greenhouse gases emitted by human activities, the warming of tropical ocean currents, and the potential eruption of solar flares. 展开更多
关键词 the north pole CLIMATE Change SCIENTIFIC EXPEDITIONS
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North Pole
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作者 黄红艳 《中学英语园地(八九年级适用)》 2008年第3期18-19,共2页
Near the North Pole there are two seasons: winter and summer. The winter nights are long. For more than two months, you can3t see the sun,
关键词 north pole
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俄罗斯北极地区油气资源潜力及加强中俄油气合作建议 被引量:2
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作者 牟德刚 孟凡洋 苗淼 《国际石油经济》 2024年第3期38-45,共8页
分析北极地区中俄油气合作的历史背景及战略意义、俄罗斯北极主要盆地油气地质特征、资源潜力以及中俄(北极)油气能源合作现状、机会与风险,提出在北极地区加强中俄油气合作的4点建议:1)在俄北极西部加大亚马尔半岛、格达半岛液化天然... 分析北极地区中俄油气合作的历史背景及战略意义、俄罗斯北极主要盆地油气地质特征、资源潜力以及中俄(北极)油气能源合作现状、机会与风险,提出在北极地区加强中俄油气合作的4点建议:1)在俄北极西部加大亚马尔半岛、格达半岛液化天然气项目的参股力度,提升“冰上丝绸之路”合作水平;2)在俄北极中部,常规与非常规并举,加快推进新兴勘探区油气勘探开发合作;3)推进双方在俄东部低勘探程度盆地开展联合油气普查和资源评价工作;4)推进技术合作攻关与交流,拓展海外工程技术服务市场。 展开更多
关键词 俄罗斯 北极地区 油气资源 油气合作
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The Subversion of Modernity and Socialism in Mu Shiying's Early Fiction
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作者 Christopher Rosenmeier 《Frontiers of Literary Studies in China-Selected Publications from Chinese Universities》 2013年第1期1-22,共22页
Mu Shiying's first short story collection, North Pole, South Pole (Nanbeiji) from 1932, is usually seen as socialist or proletarian literature preceding his later modernist writings. I argue that this view needs to... Mu Shiying's first short story collection, North Pole, South Pole (Nanbeiji) from 1932, is usually seen as socialist or proletarian literature preceding his later modernist writings. I argue that this view needs to be revised. In one short story Mu deliberately parodies the social agenda of contemporary leftist writers. The protagonists are neither enlightened workers nor victims of social injustice. On the contrary, they turn to rage, misogyny, and self-righteous violence, and their motives are rooted in their sexual frustrations and inability to cope with modem life. Their righteous ideals are based on fiction and an imagined tradition. Mu's construction of the fictive tradition plays an important part in these early short stories, and, in this respect, I compare them with Shi Zhecun's writings. 展开更多
关键词 Mu Shiying north pole South pole (Nanbeiji) Xin ganjue pal (New Sensationalism) proletarian literature
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楚科奇海与白令海表层沉积中的钙质和硅质微体化石研究 被引量:27
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作者 陈荣华 孟翊 +1 位作者 华棣 王汝建 《海洋地质与第四纪地质》 CAS CSCD 北大核心 2001年第4期25-30,共6页
通过对北冰洋楚科奇海和白令海 41个表层沉积样品中的有孔虫、介形类等钙质微体化石和硅藻、放射虫、海绵骨针等硅质微体化石的定量分析 ,发现表层沉积中浮游有孔虫几乎缺失 ,这可能与该区表层生产力相对低、碳酸盐溶解作用较强有关 ,... 通过对北冰洋楚科奇海和白令海 41个表层沉积样品中的有孔虫、介形类等钙质微体化石和硅藻、放射虫、海绵骨针等硅质微体化石的定量分析 ,发现表层沉积中浮游有孔虫几乎缺失 ,这可能与该区表层生产力相对低、碳酸盐溶解作用较强有关 ,而底栖有孔虫和硅质微体化石的丰度分布则明显受表层沉积物类型、表层初级生物生产力和碳酸盐溶解作用所控制。其中 ,北冰洋楚科奇海陆架区有孔虫丰度和分异度低 ,含少量浅水介形类 ,放射虫在陆架浅水区缺失 ,但含有较多硅藻和海绵骨针等其它硅质微体化石 ,反映该区由于海冰、表层海水温度较冷而导致表层初级生产力相对低。白令海陆坡区底栖有孔虫丰度比楚科奇海高一个数量级 ,底栖有孔虫分异度也相对高 ,硅藻、放射虫、海绵骨针等硅质微体化石的丰度与钙质化石一样 ,其丰度比楚科奇海明显高 ,反映表层初级生产力相对高。根据白令海陆坡区底栖有孔虫和硅质微体化石丰度、底栖有孔虫胶结质壳比值的水深变化 ,推测该区碳酸盐溶跃层和补偿深度 (CCD)相对浅 ,分别位于水深 2 0 0 0 m和 380 0 展开更多
关键词 微体化石 碳酸盐溶解作用 表层沉积 北极 楚科奇海 白令海 气候变化
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500hPa高度场上两极和赤道位势高度气候演变规律的研究 被引量:5
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作者 严华生 宋国琼 +1 位作者 杨素雨 李万彪 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2007年第1期58-65,共8页
本文运用近50 a来500 hPa层次上南极、赤道和北极位势高度以及南北半球西风指数的资料,分析了它们的时间演变规律及其相互间的关系.结果表明,南极位势高度显著下降;赤道位势高度显著上升.南极、赤道和北极位势高度都存在着显著的年际、... 本文运用近50 a来500 hPa层次上南极、赤道和北极位势高度以及南北半球西风指数的资料,分析了它们的时间演变规律及其相互间的关系.结果表明,南极位势高度显著下降;赤道位势高度显著上升.南极、赤道和北极位势高度都存在着显著的年际、年代际变化特征.总体上,南极位势高度与赤道位势高度有极其显著的负相关关系,北极与赤道的位势高度之间以及两极位势高度之间相关关系不显著;在共振的特定频率中,北极位势高度振荡落后于南极位势高度,赤道位势高度振荡又落后于两极位势高度振荡,气候变化最先开始的区域为南极地区.进一步分析表明,伴随着以上三个区域的位势高度趋势变化及其周期振荡,必然引起高空西风的增强与周期振荡.研究表明,南北两半球西风指数都存在显著的上升趋势,且存在显著的年代际变化特征.其中,南半球西风指数上升幅度较北半球大,其振荡落后于南极位势高度. 展开更多
关键词 北极 赤道 位势高度 西风指数
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地震仪器定向与磁偏角 被引量:9
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作者 吕永清 蔡亚先 程骏玲 《大地测量与地球动力学》 CSCD 北大核心 2006年第2期120-123,共4页
在安装地震仪器时,方位精度要求到6′,而在许多台站的摆房里预先没有划好方位线,故不得不借助罗盘定向,且必须用磁偏角修正。阐述了磁偏角的变化,提出了计算磁偏角的方法,推出了实用的计算公式。
关键词 地震仪器定向 磁偏角 罗盘 磁北极 地理北极
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中国二代卫星导航系统设计覆盖范围的探讨 被引量:19
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作者 郝晓光 陈晓峰 +2 位作者 张赤军 柳林涛 胡小刚 《大地测量与地球动力学》 CSCD 北大核心 2007年第1期119-122,共4页
根据“北半球版世界地图”表示的概念,探讨了中国二代卫星导航系统的设计覆盖范围。指出其往东即向太平洋方向延伸的设计较合理,而往北极方向的延伸距离不足。此设计有可能影响二代卫星导航系统作用的发挥,建议增加中国及周边地区的覆... 根据“北半球版世界地图”表示的概念,探讨了中国二代卫星导航系统的设计覆盖范围。指出其往东即向太平洋方向延伸的设计较合理,而往北极方向的延伸距离不足。此设计有可能影响二代卫星导航系统作用的发挥,建议增加中国及周边地区的覆盖范围。 展开更多
关键词 北半球版世界地图 卫星导航系统 覆盖范围 北极方向 中国周边地区
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1962-2010年潜在干旱对中国冬小麦产量影响的模拟分析 被引量:10
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作者 曹阳 杨婕 +3 位作者 熊伟 武永峰 冯灵芝 杨晓光 《农业工程学报》 EI CAS CSCD 北大核心 2014年第7期128-139,共12页
旱灾是冬小麦生产中常见的气象灾害,该研究旨在了解气候变化背景下中国冬小麦小麦受干旱的历史影响及变化情况,这对合理指导冬小麦生产的减灾、防灾,稳定冬小麦产量有重要的指导意义和作用。该研究采用CERES-Wheat模型,模拟了1962-2010... 旱灾是冬小麦生产中常见的气象灾害,该研究旨在了解气候变化背景下中国冬小麦小麦受干旱的历史影响及变化情况,这对合理指导冬小麦生产的减灾、防灾,稳定冬小麦产量有重要的指导意义和作用。该研究采用CERES-Wheat模型,模拟了1962-2010年潜在干旱对中国冬小麦产量影响的时空变化趋势,并分析其与大气环流因子间的关系,以期了解中国近50a来冬小麦受旱程度的变化情况。结果表明:1)1962-2010年中国冬小麦因干旱造成的潜在产量损失总体呈上升的趋势,但不同时期表现不同,其中20世纪60年代、20世纪80年代表现为下降趋势。2)在过去近50a里,中国冬小麦潜在旱灾产量损失中心有向西北移动的趋势,这主要是受黄土高原和河西走廊地区受旱程度增强的影响。3)中国冬小麦潜在旱灾产量损失中心的经纬度和影响中国降水的副热带高压、北极涡系统的部分指数具有显著的负相关关系。冬小麦生长季同期(前一年10月-当年5月)的副热带高压系列指数与中心的相关关系表现显著,而生长季同期和生长季前期(前一年6月-前一年9月)的北极涡系列指数与中心都具有显著的相关关系。当冬小麦生长季同期北半球的西太平洋副高、印度副高和南海副高的强度偏强、范围偏大时,潜在旱灾产量损失中心的位置将会偏西;当北极涡在冬小麦生长季前期或同期偏大偏强时,中国冬小麦潜在产量损失中心将偏南,反之亦然。 展开更多
关键词 干旱 农作物 模型 冬小麦 副热带高压 北极涡
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华北基性岩墙群的古地磁极及其哥伦比亚超大陆重建意义 被引量:17
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作者 侯贵廷 Henry HALLS +3 位作者 Don DAVIS 黄宝玲 杨默函 王传成 《岩石学报》 SCIE CAS CSCD 北大核心 2009年第3期650-658,共9页
从华北克拉通的中西部和东部发育的基性岩墙群获得三个精确定年的实际古地磁极位置(VGPs)。华北克拉通中西部恒山GU岩墙的斜锆石U-Pb年龄为1769±3Ma,该岩墙的古地磁给出古地磁极位置在北纬36°,东经247°(dp=2,dm=4);华北... 从华北克拉通的中西部和东部发育的基性岩墙群获得三个精确定年的实际古地磁极位置(VGPs)。华北克拉通中西部恒山GU岩墙的斜锆石U-Pb年龄为1769±3Ma,该岩墙的古地磁给出古地磁极位置在北纬36°,东经247°(dp=2,dm=4);华北克拉通东部DY岩墙的斜锆石U-Pb年龄为1620.8±6.9Ma,获得的古地磁极位置为北纬6.9°东经81.9°(dp=4.31,dm=6.09);东部另一条岩墙LW4的SHRIMP U-Pb年龄为1157±18Ma,获得的古地磁极位置为北纬27.1°东经162°(dp=15.8,dm=18.7)。通过将这三个从基性岩墙获得的华北克拉通古地磁极位置与加拿大地盾的中元古代视极移曲线对比,在中元古代早期(1800~1600Ma),华北克拉通与加拿大地盾一起同属哥伦比亚超大陆,而在中元古代晚期(1600~1200Ma),华北克拉通与加拿大地盾分离,响应哥伦比亚超大陆的最终裂解事件。 展开更多
关键词 基性岩墙群 古地磁极 华北克拉通 加拿大地盾 哥伦比亚超大陆
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北方冬季植物配置与造景的简约设计 被引量:5
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作者 杨芳绒 苏志国 李卓 《北方园艺》 CAS 北大核心 2007年第12期137-139,共3页
北方的冬季自然景观单调。在城市中,塑造良好的冬季植物景观就变得非常重要。通过对郑州、北京、哈尔滨3个北方城市的冬季植物景观的现状调查,分析了植物冬季形态特征和市民休闲需求,认为简约设计是冬季植物配置与造景的适宜手法。
关键词 北方 冬季 植物景观 简约
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