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991.
992.
长期以来,由于矿山地下水疏放工作缺乏科学的规划和管理,造成地下水资源大量浪费并引发了一系列环境地质问题。目前,解决矿山采煤"疏水和保水"矛盾的最有效方法,就是对地下水资源的疏放进行合理优化和分配。为此,本文采用最优化方法,以安徽淮南潘北煤矿西翼采区为研究对象,在分析水文地质条件和构建水文地质模拟模型基础上,建立了以水位和疏放量为约束条件,以最小疏放量为目标函数的目标规划管理模型。根据模型的最优解,对区内疏放水钻孔进行了重新分配和布置,使得A煤层的开采时间由22年后缩短为5年之内,地下水疏放量由2.31×107m3减少为1.19×10~7m~3,并经现场实际验证,该模型是正确、可行的。这将为今后类似条件下的矿山疏放水工作提供一定的借鉴作用。 相似文献
993.
994.
Nguyen Dinh Chau Paweł Jodłowski Stefan J. Kalita Paweł Olko Edward Chruściel Adam Maksymowicz Michał Waligórski Paweł Bilski Maciej Budzanowski 《Acta Geophysica》2008,56(2):505-517
The doses of gamma radiation, concentrations of radium isotopes in water and sediments, radon concentration and concentration
of alpha potential energy of radon decay products in the copper ore mine and in the mining region in the vicinity of Lubin
town in Poland are presented. These data served as a basis for the assessment of radiological hazard to the mine workers and
general public. The results of this assessment indicate that radiological hazard in the region does not differ substantially
from typical values associated with natural radiation background. The calculated average annual effective dose for copper
miners is 1.48 mSv. In general, copper ore mines can be regarded as radiologically safe workplaces. 相似文献
995.
以地层等高线和地质柱状图为建模基础信息,采用曲面样条函数进行插值计算地质曲面,并对AutoCAD进行二次开发,将二维抽象的等高线信息以三维可视化的图形效果在AutoCAD的图形窗口中直观形象地表示出来,为开采和规划决策提供依据.此方法可使煤矿主采区域、城市活断层探测以三维地层显示,对煤矿行业,地震活断层研究有一定的参考价值. 相似文献
996.
选取首都圈地区2008年8月——2009年9月ML在2.0——2.2范围内的爆破、矿塌和天然地震数据资料,从时间域和频率域进行分析对比,总结出识别爆破、矿塌和天然地震的依据.在时域方面,爆破的初动方向向上,矿塌向下,天然地震的初动方向依赖于台站的分布情况;爆破和矿塌的面波比较发育;天然地震的S波与P波最大振幅比(AS/AP)大于爆破和矿塌,同时,爆破和矿塌的能量衰减比天然地震快.在频域方面,高频成分的能量衰减快于低频;天然地震的拐角频率较高,爆破次之,矿塌的最小;在震中距200 km范围内,爆破的顶峰频率主要分布在5——7 Hz,矿塌分布在2——4 Hz,天然地震的顶峰频率较大,在10——18 Hz范围内.另外,天然地震的频率域较宽,其次为爆破、矿塌. 相似文献
997.
矿区震动能诱发多种灾害,以瓦斯突出尤为严重。以鹤岗矿区为研究对象,统计了历年来鹤岗地区地震及矿震活动规模,分析了以往典型的矿震引起的瓦斯灾害事例,总结了矿震作用下瓦斯灾害的机理,基于统计数据,提出了矿震瓦斯灾害预警需要解决的关键问题。初步研究表明:震动事件与煤矿灾害之间具有很强的关联性,呈现震动在前、灾害在后、时间间隔数分钟至数日不等的“先震后灾”的特点,基于此,通过建立矿震监测台网,给出了震动诱发煤矿瓦斯灾害预警可行性,并提出了震动引起瓦斯灾害预警思路。 相似文献
998.
Masayuki Sakakibara Yuko Ohmori Nguyen Thi Hoang Ha Sakae Sano Koichiro Sera 《洁净——土壤、空气、水》2011,39(8):735-741
Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log‐linear fashion. The bioconcentration factor for these elements decreases log‐linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals. 相似文献
999.
Abstract This paper considers the complexity in resolving the conflicts between mine drainage, water supply, and environmental protection for the coal basin of North China, and presents a management optimization framework that addresses these multiple conflicting issues simultaneously in the most cost effective manner. Due to the various unpredictable accidents which may occur in the coal mining process, such as water bursts, gas leaks, fire and collapse of coal beds, the beneficial use of drainage water from the coal mines is generally low. This case study attempts to address the problem of low beneficial usage for drainage water using the Jiaozuo coal mining district in Henan Province, China. By combining a finite-element groundwater simulation model with an optimization code, the economic benefits of using the drainage water as a stable water supply is maximized, while the adverse impact of mine drainage on the environment is controlled. The results indicate that the management model developed in this study achieves an excellent economic outcome and can serve as a potentially powerful tool for solving mining-related water management problems in the coal basin of North China. Citation Wu, Q., Hu, B. X., Wan, L. & Zheng, C. (2010) Coal mine water management: optimization models and field application in North China. Hydrol. Sci. J. 55(4), 609–623. 相似文献
1000.
There is a need to assess the long-term stability of engineered landforms associated with the rehabilitation of Ranger Uranium Mine, Northern Territory, Australia, as it is a requirement that mill tailings must be contained for periods in excess of 1000 years. The geomorphic model, SIBERIA, is calibrated on hydrologic and erosion data collected by a combination of monitoring and rainfall simulation experiments on the waste rock dumps of Ranger. Preliminary analysis of Ranger's preferred above-grade option suggests that erosion of the order of 7 to 8 m will occur on the structure in a period of 1000 years. This depth of erosion may be sufficient to compromise the integrity of containment. It is shown that SIBERIA has significant advantages over steady-state erosion models. Suggestions are made for the design that will enhance the stability of the structure and extend the structural life of the containment. © 1998 John Wiley & Sons, Ltd. 相似文献