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551.
Well blowout rates in oil fields undergoing thermally enhanced recovery (via steam injection) in California Oil and Gas District
4 from 1991 to 2005 were on the order of 1 per 1,000 well construction operations, 1 per 10,000 active wells per year, and
1 per 100,000 shut-in/idle and plugged/abandoned wells per year. This allows some initial inferences about leakage of CO2 via wells, which is considered perhaps the greatest leakage risk for geological storage of CO2. During the study period, 9% of the oil produced in the United States was from District 4, and 59% of this production was
via thermally enhanced recovery. There was only one possible blowout from an unknown or poorly located well, despite over
a century of well drilling and production activities in the district. The blowout rate declined dramatically during the study
period, most likely as a result of increasing experience, improved technology, and/or changes in safety culture. If so, this
decline indicates the blowout rate in CO2-storage fields can be significantly minimized both initially and with increasing experience over time. Comparable studies
should be conducted in other areas. These studies would be particularly valuable in regions with CO2-enhanced oil recovery (EOR) and natural gas storage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
552.
ZHANG Xiaoyu LI Chunlai L Chang Graduate University of Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China 《中国地球化学学报》2009,28(2):204-211
In the second phase of the Chang’E Program an unmanned lunar rover will be launched onto the Moon. When ground scientists
get a full understanding of the chemical composition of lunar soil around the rover, they can make more detailed survey plans
for the rover and various payloads onboard so as to satisfy their scientific objectives. There is an obvious relationship
between the reflectance of lunar soil and its chemical characteristics. Both principal component analysis (PCA) and support
vector machine (SVM) models were applied to establishing the relationship between the reflectance spectra and chemical compositions
of lunar highland and mare soil samples sent back by Apollo missions 11, 12, 14, 15, 16 and 17 and measured by Lunar Soil
Characterization Consortium (LSCC). PCA was used to reduce and select the features of the reflectance spectra of lunar soil
samples. Then, these features were put into SVM to estimate the abundances of various chemical components in lunar soil. We
also compared the results of our measurement with those obtained by the SVM model [partial least squares (PLS)] and the principal
component regression (PCR) model reported in literature. Our studies showed that with the exception of TiO2, the results of prediction of the abundances of chemical compounds in lunar soil by our model are much more reliable than
those reported in literature. The reflectance spectra of lunar soil are closely related to the materials from which it was
derived. 相似文献
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中国油田以注水开发为主,目前其平均采收率在33%左右。笔者研究认为,制约注水开发的一个重要因素是注入水温度明显低于油层温度,由此引发一系列问题,诸如注入水温度低造成油层温度持续下降,增大了原油黏度。长期剧烈的温差导致储层孔喉胶结物及骨架矿物破碎,加剧了大孔道窜流。笔者针对目前注入水温度过低对油田开发效果的不利影响,提出了一些建设性意见,诸如尽可能选择污水回注,前提是水质达标。主要是考虑到采出的地层水矿化度比较高,与油层配伍性比较好,有利于获得较高的驱油效率。同时减少污水治理和外排压力,更有利于环保和清洁生产。尽可能提高注入水的温度,缩小注入水与油层的温度差距,如果采用高于油层温度的热水驱油最为理想。由于注入水流程比较长,受地面环境温度影响较大,基于夏季注入水温度大大高于冬季注入水温度,能否考虑采取不对称注水方式,即夏季注采比高一些,冬季低一些。同时尽量缩短注水流程长度,尽可能减少沿途热损失。尽可能少注水。在满足油田地层能量补充的前提下,尽最大可能减少注水量,同时减少管外窜槽井治理、平面大孔道井治理、只注不采井治理和特高含水且高液量井治理,减少无效注水。本文围绕提高注入水温度,着重讨论地热、太阳能辅助采油构想。... 相似文献
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月壤钛铁矿微波烧结制备月球基地结构材料的初步设想 总被引:2,自引:0,他引:2
月球基地建设是当前"重返月球"的一个重要目标,为满足其建设需要大量结构材料.部分学者通过对真实月壤样品和模拟月壤进行各种高温烧结实验,分析了就地利用月壤矿物资源制备各种材料的方法.但由于月壤成分较为复杂,烧结产物的性能还很难满足实际需求.微波烧结技术作为一项新技术,具有传统烧结技术无法比拟的优势,更适合作为月球资源利用中的烧结加热技术.结合月壤中钛铁矿的含量,通过热力学分析,作者认为利用钛铁矿进行微波烧结实验来制备月球基地所需结构材料是一个值得深入研究的方案. 相似文献
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两种常用染色剂管道及淤泥条件下示踪及对比——以丁旗地下河连通试验为例 总被引:3,自引:3,他引:0
通过对丁旗地下河同一投放点同时开展二元示踪试验,探讨了当前被忽略的不同示踪剂应用对比及回收率合理性等问题。在淤泥沉积的地下河管道及流量和浊度稳定条件下,得出主要结论:(1)荧光素钠、罗丹明B回收率分别为53.91%和40.72%,前者比后者少损失13.19%;其中荧光素钠在主峰和缓慢衰减段排出量分别占85.03%和14.97%,罗丹明B则对应为65.88%、34.12%;(2) 荧光素钠对应峰值的回收强度为罗丹明B的2.95倍且最大峰值出现时间比后者提前2 h;(3) 罗丹明B由于吸附等形成的浓度曲线对管道结构分析有可能产生误导,荧光素钠则相对更准确。 相似文献