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301.
302.
A May 2007 tornado destroyed 95% of aging, declining Greensburg, Kansas. The city took the opportunity to build back “stronger,
better, and greener,” enforcing upgraded codes, requiring city-owned buildings to meet LEED Platinum level standards, and
recommending energy-efficiency housing in a new Sustainable Comprehensive Plan. Using information collected from surveys of
Greensburg tornado survivors, interviews, and publications, we examined the housing-related recovery, including the emergency
provision of temporary shelter and rebuilding permanently. Although temporary shelter kept residents nearby for rebuilding,
given the gap between insurance policy limits on the aging housing stock and rebuilding costs, housing affordability is a
critical issue in Greensburg’s recovery. Local, state, and federal support have made construction of municipal buildings at
LEED Platinum level and some affordable and green housing projects possible. However, far greater public and private sector
funding for affordable workforce housing, in conjunction with broader economic and job development, is needed. 相似文献
303.
Ground snow observation data from 1999 to 2008 were used to analyze the temporal and spatial distribution of snow density in
China. The monthly maximum density shifted from north to south during the period from October to the following January, and
then moved back from south to north during the period from January to April. The maximum snow density occurred at the border
between Hunan and Jiangxi provinces in January, where snow cover duration was short and varied remarkably. Snow density in
Northeast China and the Xinjiang Uygur Autonomous Region were also high and showed less variation when the snow cover duration
was long. Ground observation data from nine weather stations were selected to study changes of snow density in Northeast
and Northwest China. A phase of stable snow density occurred from the middle ten days of November to the following February;
non-stationary density phases were observed from October to the first ten days of November and from March to April. To further
investigate the effects of climatic factors on snow density, correlations between snow density and precipitation, air temperature,
snow depth and wind velocity for Northeast and Northwest China were analyzed. Correlation analysis showed that snow depth was
the primary influence on snow density. 相似文献
304.
在北京太平庄井详细观察观测与研究了井水位、水温、流量、水化学离子、溶解气与逸出气及井区土壤气与气象因素等37项地下流体及其影响因素的短期动态。根据试验观察结果,本文初步解释出以地固体潮、大气大无畏民不动力条件的变动为共同基础的该井各测项短期-动态的内在联系,文中还对比分析了溶解气-逸出气-土壤气,水温-地温-气温等同类测项动态间的联系。 相似文献
305.
硅元素是地球第二大组成元素,深刻影响着地表物质循环,是陆海相互作用研究、全球碳循环研究的关键元素之一.从自然风化、生物过程和人类活动3个方面综述了国内外有关地表过程对硅产出影响的研究进展,重点分析了生物过程和人类活动在硅生物地球化学循环过程中的作用.综合分析指出,应着重开展生物参与下原生/次生硅酸盐矿物风化速率的研究,重视高等植物在区域硅循环中的作用;富营养化与筑坝对于河流硅的滞留都十分重要,因筑坝产生的水库清水下泄在中下游河道产生的潜在效应很可能对河口硅输入产生重要的影响.应采用地球化学示踪技术,加强这方面的定量研究、模型研究、过程研究以及系统的综合性研究,特别是对流域地表过程的改变以及与筑坝、富营养化过程的联合作用,应进行深入的多学科交叉综合研究. 相似文献
306.
奶牛隐性乳房炎发生规律探讨 总被引:2,自引:0,他引:2
通过对某奶牛场泌乳牛群隐性乳房炎的调查和分析 ,研究了奶牛隐性乳房炎的发生规律。结果表明 ,该场奶牛隐性乳房炎的阳性率为 31.4 2 %、乳区临诊阳性率达到 10 .6 0 % ;隐性乳房炎的发生随着胎次和泌乳时间的增加而增加 ;左乳区阳性率高于右侧 ,前乳区高于后乳区。在牛群(场 )里进行经常性的临床和实验室检验是必要的。 相似文献
307.
The X-ray fluorescence and ICP methods were used to analyze 60 outcrop samples of black shale, of which 15 were collected from Belait, 15 from the Setap Shale, 15 from Temburong, and 15 from the Trusmadi formations. The average compositions of the shales from the study area are 64.62%, 63.95%, 62.32%, 63.84% SiO2, 1.84%, 2.14%, 2.04%, 1.99% MgO, 2.55%, 3.12%, 2.89%, 2.72% K2O, 0.32%, 0.30%, 0.32%, 0.53% CaO, 5.86%, 6.06%, 7.14%, 6.60% Fe2O3, 207×10^-6, 180×10^-6, 213×10^-6, 200×10^-6 Rb, and 56×10^-6, 49×10^-6, 50×10^-6, 32×10^-6 Sr for the Setap Shale, Temburong, Belait and Trusmadi samples, respectively. The high Rb/Sr ratios of 3.8, 3.7, 4.2, and 6.1 are attributed to the lowest contents of Sr due to reducing conditions prevailing. The high Rb/K ratio sug- gests either brackish marine or rapid deposition that prevented equilibrium between Rb and K in the shales and marine waters. 相似文献
308.
With an increase in model resolution, compact high-order numerical advection scheme can improve its effectiveness and competitiveness in oceanic modeling d 相似文献
309.
Jie Wang Mingjun Zhang Shengjie Wang Zhengguo Ren Yanjun Che Fang Qiang Deye Qu 《地理学报(英文版)》2016,26(9):1277-1288
On the basis of two gridded datasets of daily precipitation and temperature with a spatial resolution of 0.5°×0.5°, and meteorological station data released by the National Meteorological Information Center (NMIC) during 1961–2013, the spatial and temporal variations of total amount of precipitation, amount of rainfall, amount of snowfall and snowfall/rainfall ratio (S/R) in the Tibetan Plateau (TP) are analyzed using Sen’s slope, the Mann–Kendall mutation test, Inverse Distance Weighting (IDW) and the Morlet wavelet. Total amount of precipitation and amount of rainfall generally show statistically significant increasing trends of 0.6 mm·a–1 and 1.3 mm·a–1, respectively, while amount of snowfall and S/R have significant decreasing trends of–0.6 mm·a–1 and–0.5% a–1, respectively. In most regions, due to significant increasing trends in total amount of precipitation and amount of rainfall, and significant decreasing trends in amount of snowfall, S/R shows a decreasing trend in the TP. Abrupt changes in total amount of precipitation, amount of rainfall, amount of snowfall and S/R are detected for 2005, 2004, 1996 and 1998, respectively. Total amount of precipitation, amount of rainfall, amount of snowfall and S/R are concentrated in cycles of approximately 5 years, 10 years, 16 years and 20 years, respectively. The trend magnitudes for total amount of precipitation and amount of rainfall all show decreasing-to-increasing trends with elevation, while amount of snowfall and S/R show decreasing trends. 相似文献
310.
东北地区的创新能力演化及其经济带动作用分析 总被引:5,自引:2,他引:3
通过建立创新能力指标体系和计算模型,并采用相关分析、回归分析、变异系数等方法,从不同空间层级剖析了东北三省的创新能力发展格局及其对经济发展的带动作用,并根据研究结果提出了相关政策建议。研究发现:① 从创新能力分析,吉林、辽宁的创新能力增长较快而黑龙江相对较慢,省际差异呈扩大态势;地级市之间的创新能力相差悬殊,呈现明显的省会城市及门户城市集聚效应,但市级差异呈缩小态势。② 从创新贡献率分析,辽宁的科技创新转化能力及其对经济发展的带动相对较强,而吉林、黑龙江相对较弱;地级市差异较大,沈阳、大连、长春、大庆的创新贡献率比较突出,而锦州、吉林、盘锦、铁岭上升较快。③ 大部分地级市的创新发展对经济带动模式为“低创新能力-弱经济带动”和“高创新能力-强经济带动”,说明各地级市的创新发展及其对经济带动的两极分化较严重。 相似文献