全文获取类型
收费全文 | 448篇 |
免费 | 5篇 |
国内免费 | 24篇 |
专业分类
安全科学 | 148篇 |
废物处理 | 14篇 |
环保管理 | 41篇 |
综合类 | 175篇 |
基础理论 | 14篇 |
污染及防治 | 45篇 |
评价与监测 | 28篇 |
社会与环境 | 5篇 |
灾害及防治 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 2篇 |
2021年 | 12篇 |
2020年 | 12篇 |
2019年 | 1篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2016年 | 12篇 |
2015年 | 14篇 |
2014年 | 26篇 |
2013年 | 29篇 |
2012年 | 39篇 |
2011年 | 20篇 |
2010年 | 8篇 |
2009年 | 21篇 |
2008年 | 22篇 |
2007年 | 13篇 |
2006年 | 18篇 |
2005年 | 12篇 |
2004年 | 21篇 |
2003年 | 25篇 |
2002年 | 11篇 |
2001年 | 18篇 |
2000年 | 15篇 |
1999年 | 31篇 |
1998年 | 22篇 |
1997年 | 17篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有477条查询结果,搜索用时 250 毫秒
211.
煤层注水中水分蒸发现象的研究 总被引:2,自引:0,他引:2
对煤层注水的水分蒸发现象进行了研究 ;提出了注入水分蒸发的力学平衡公式 ;研究了影响水分蒸发的各项因素。在此基础上 ,提出了在注水钻孔中添加粘尘棒 ,阻止注入水分过早蒸发的新方法 ,并进行了纯水和粘尘棒溶液在煤体中蒸发的试验。 相似文献
212.
基于山西省王庄煤矿采煤塌陷和废弃物压占土地等主要环境问题和矿区生态条件,提出了生态恢复模式设计主要包括平面结构、垂直结构、食物链网、时间节律和工程措施等五项内容,并在此基础上优化集成了立体共生、设施农业、物质循环、农林鱼禽系统、旅游景观开发、科普园区设计等六种生态恢复模式;最后在典型塌陷区进行了经济、社会和生态效益的示范性评价,结果良好。这一切均为建设生态矿区、和谐矿区提供了理论依据。 相似文献
213.
本文按照《环境影响评价技术导则地下水环境》(HJ610-2011)的要求,结合煤炭开采对地下水的影响方式,从评价等级及评价范围的确定,现状调查内容和评价、预测内容和方法、地下水保护措施、地下水动态监测等方面提出了煤矿地下水环境影响评价的要点,为煤矿项目地下水环境影响评价提供参考。 相似文献
214.
215.
Policy shocks affect the rent distribution in long-term contracts, which can lead to such contracts being renegotiated. We seek an understanding of what aspects of contract design, in the face of a substantial policy shock, affect the propensity to renegotiate. We test our hypotheses using data on U.S. coal contracts after the policy shock of the 1990 Clean Air Act Amendments. Contracts are divided into two categories, those that were renegotiated following the shock and those that were not. Characteristics of the contract are used to explain whether or not the contract was ultimately renegotiated. Results provide guidance on rent re-distribution and contract renegotiation more generally and are applicable to contemporary policy issues such as climate change legislation. 相似文献
216.
217.
矿井安全评价中的几个问题的初步研究 总被引:1,自引:0,他引:1
研究了矿井灾害系统危险评价中的几个关键问题,分析了煤矿灾害系统的结构特点,针对矿井灾害系统这样一个过程性本质模糊的灾害发生环境,提出了危险程度的模糊风险度量理论和基于此理论的定量表示方法,以及对不同灾害事故后果相关性计算方法。还论述了全矿与其各组成部分的危险程度之间的相互关系。 相似文献
218.
Olga Popovichev Elena Molozhnikov Sergey Nasonov Vladimir Potemkin Ivan Penner Marina Klemashev Irina Marinaite Ludmila Golobokov Stergios Vratolis Konstantinos Eleftheriadis Tamara Khodzher 《环境科学学报(英文版)》2021,33(9):49-64
Lake Baikal is the biggest reservoir of fresh water with unique flora and fauna; presently it is negatively affected by climate change, water warming, industrial emissions, shipping, touristic activities, and Siberian forest fires. The assessment of air pollution - related Baikal's ecosystem damage is an unsolved problem. Ship, based expedition exploring the Baikal atmospheric aerosol loading, was performed over the lake area in July 2018. We combine the aerosol near - water and vertical distributions over the Lake Baikal basin with meteorological observations and air mass transportation simulations. Lidar sounding of aerosol fields in the troposphere assesses the atmospheric background in the pristine areas and the pollution during fire-affected periods. Aerosol optical properties (scattering and spectral absorption) converted to the particle number size, black carbon (BC) mass, and Absorption Angstrom Exponent (AAE) provide the inside into aerosol characterization. Transport of industrial emissions from Krasnoyarsk and Irkutsk regions, and wildfire plumes from Republic of Yakutia relates the pollution sources to the increased concentrations of fine particle numbers, PM10 and BC mass over Southern and Northern/Central Baikal, respectively. The highest PM10 and BC are associated to the harbor and touristic areas of intensive shipping and residential biomass burning. Deposition estimates applied to aerosol data exhibit the pollution fluxes to water surface over the whole Baikal area. AAE marks the impact of coal combustion, residential biomass burning, and wildfires indicating the high pollution level of the Lake Baikal ecological system . 相似文献
219.
Ventilation plays an important role in the spontaneous heating of coal in an underground coal mine. If the ventilation rate is too high, heat is carried away by convection. If the ventilation rate is too low, the reaction rate becomes oxygen-limited. The effect of ventilation on the spontaneous heating of coal was investigated in an isothermal oven in this study. Experiments were conducted on three U.S. coal samples with ventilation rates ranging from 100 to 500 cm3/min. Experiments under ventilation were conducted to determine the critical ambient temperature, which is the minimum oven temperature required for a coal sample to achieve thermal runaway. Spontaneous heating tests were then conducted at various ventilation rates at the critical ambient temperature and the results were compared with spontaneous heating tests without ventilation. It was found that there is an optimum ventilation flow to produce the maximum rate of temperature rise at the critical ambient temperature. When the coal sample particle size was increased, a higher critical ambient temperature was required. The results in this study have application in the prevention of spontaneous combustion in underground coal mines. 相似文献
220.
Safety line method for the prediction of deep coal-seam gas pressure and its application in coal mines 总被引:2,自引:0,他引:2
Gas pressure is an important index for evaluating the outburst risk and determining the gas content in coal seams. It is recommended to predict coal-seam gas pressure of the workface at deep levels before extending mining activities to deeper levels. According to the prediction results, measurements are taken for gas outburst prevention and control and for workload estimation. At present, regression methods are always used to process the numerous gas pressure data for prediction. Because there are many factors that influence the gas pressure which could lead to a deviation from actual values, the measured data do not possess basic conditions for regression methods; this can cause unexpected dangers if the methods are adopted.Based on a statistical analysis of actual measured results of coal-seam gas pressure in a same geological section in certain coal mine, two symbol measured points are selected to make a line for prediction, i.e. safety line, and the other measured points should be below the line except the abnormal points due to the confined water. It has been successfully applied in numerous coal mines in China. Particularly, this method is analyzed in this paper for the case of the No. 82 coal seam in the Taoyuan coal mine in Huaibei coalfield, China. By comparatively analyzing the relationship between gas pressure and depth from surface using regression methods, it is found that the safety line method could lead to a better prediction for deep coal-seam gas pressure, and therefore promote early warning ability and mining safety. 相似文献