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41.
锚杆(索)加固边坡的最小势能稳定分析方法研究 总被引:2,自引:1,他引:1
最小势能边坡稳定性分析方法是一种正处于发展完善中的新型边坡稳定分析方法。建立了采用锚杆(索)加固边坡后的最小势能稳定分析新方法,并进一步提出了一个考虑滑床剪切势能影响的近似计算模型,算例表明:(1)最小势能边坡稳定分析方法的结果,不论有无锚固均与现在工程常用的极限平衡方法的结果较为一致,表明了这一新方法的适用性;(2)滑床剪切势能计算模型引进与否对单一地层边坡的安全系数影响微小,可忽略不计,而对多地层边坡有较明显影响。总之,最小势能方法求取安全系数的过程简洁、概念明确合理、结果可显式表示,与极限平衡方法或有限元方法等方法相比,更具有实用价值。 相似文献
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介绍了利用GPS掩星资料反演大气重力波势能的方法,给出了从COSMIC(constellation observing system for meteorology, ionosphere and climate)干温廓线出发,扰动温度廓线提取及势能廓线反演的具体流程,进而对2011年夏季和冬季20~30 km重力波势能的全球分布及季节变化特征进行了分析,结果与国内外已有文献基本一致。 相似文献
43.
Hydrocarbon—Generating Characteristics of Barkinite—Rich Colas from Late Permian Longtan Formation ,South China 总被引:1,自引:0,他引:1
孙旭光 《中国地球化学学报》2000,19(3):227-232
Leping coal (including barkinite-rich coal) is a unique kind of coal,which is widely distrbuted in the Late Permian Longan Formation,South China,In this paper,ROck-Eval,Py-GC and simulation experiment via an open-system were used to study the hydrocarbon-generating potential,hydrocarbon composition.and hydrocarbon-generating model of barkiniterich coals from the shuicheng coal field of Guizhou Province,Southwest China.The results show that barkinite-rich coals have high hydrocarbon-generating potential,with S1 S2 being 211-311mg/g,and can produce large amounts of hydrocorbon at the high-maturity stage,mostly within the temperature range of 420-450℃(corresponding to VR0 1.1-1.5%);barkinite-rich coal is one of the better oil sources and light hydrocarbon and wet gas are the major hydrocarbon components,which account for 45% and 33% of the total hydrocarbons.respectively.These characteristics are of importance for exploring oil and gas resources in the Late permian Longtan Formation coals,southwest China. 相似文献
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对流层中层大气能量转换特征与暴雨激发和维持的关系 总被引:2,自引:0,他引:2
利用NCEP/NCAR再分析资料和中国2 513个测站逐日降水资料,分析了2008年9月22—27日四川盆地持续性暴雨过程中对流层中层大气风场动能和势能的相互转换和分布特征。结果表明,在暴雨迅速发展阶段,受环流形势和地形等条件的影响,动能能量转换成驻波形式的波动势能;在强降水维持并减弱阶段,动能和势能之间的转换趋于平缓。在整个暴雨过程中,强降水区与500hPa风场能量大值区分布基本一致。此外,台风"黑格比"也为此次暴雨过程提供了必要的水汽。 相似文献
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利用2019年1月1—7日AIRS观测的(80°—100°W,30°—45°N)范围内0—45 km高度的大气温度剖面数据,根据重力波的线性理论,分别采用垂直滑动窗口法、双滤波器法、单滤波器法对温度廓线数据进行处理,从中得到初始扰动剖面,再使用分离出来的对流层到平流层低层的背景温度和重力波扰动剖面计算重力波势能,最后根据提取结果比较三种方法的差异。结果表明:1) 采用垂直滑动窗口法提取的重力波势能对波长较小的波动有很好的反映,在对流层顶区域重力波势能异常偏大。2) 采用双滤波器法提取的重力波势能很好地反映各个波长的波动,更符合真实情况。3) 采用单滤波器法能够提取波长较大的重力波扰动,且扰动在对流层贡献更大;而采用双滤波器提取的重力波扰动分别在对流层顶和平流层贡献更大。 相似文献
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在经典的四阶Runge-Kutta(简记为RK)方法的基础上,得到一种新的解Schrdinger方程的修正的RK方法,并证明这个方法的代数阶为4。这个方法的稳定性和相性质分析也在本文中给出,新方法的相误差阶为6,耗散误差阶为5,并且通过数值试验证明了新方法的高效性。 相似文献
50.
THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER—SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR 总被引:5,自引:0,他引:5
The Hexi Corridor is an important base of agriculture development in Northwest China. According to recent statistics, there
are 65.94×108m3 of water resources available in the Hexi Corridor. At present, net consumption in development and utilization is 43.33×108m3. Water supply and demand reach a balance on the recent level of production, but loss of evaporation and evapotranspiration
is as much as 25.69×108m3. So net use efficiency of water resources is 59%. Based on analyzing balance between water and land considering ecological
environment at present, there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded.
There is a comparative balance between supply and demand of water resource in the Heihe River system; and the Sule River system
has some surplus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass
for 6.9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water-saving efficiency
of irrigation is about 10% by using such traditional technologies as furrow and border-dike irrigation and small check irrigation,
and water-saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. cansave more
than 60% of irrigated water. Incremental irrigation area for water-saving potential in the Hexi Corridor has been estimated
as 56% – 197% to original irrigation area. So the second water sources can be developed from water saving agriculture in the
Hexi Corridor under Development of the Western Part of China in large scale. This potential can be realized step by step through
developing the water-saving measures, improving the ecological condition of oasis agriculture, and optimizing allocation of
water resources in three river systems.
Foundation item: Under the auspices of the Key innovation Project Engineering of Chinese Academy of Sciences (KZcx-1-10-03)
Biography: GAO Qian-zhao (1942 –), male, a native of Changzhou, Jiangsu, Professor and supervisor of Ph. D students. His research
interests include hydrology and rational utilization of water resources in the arid zone. 相似文献