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371.
372.
煤矿安全生产调度指挥信息系统及其应用 总被引:4,自引:0,他引:4
介绍了煤矿安全生产指挥信息系统的由来、组成、特点、功能及其效果与前景。该系统以对煤矿安全生产指挥决策信息支持为目的 ,集矿山安全、工况监测及生产调度信息的采集、实时传输处理、图像 /图形显示、图形和数据存储管理及输出为一体 ,已在平煤集团公司多个矿区安装使用 ,产生了较好的经济效益及社会效益。 相似文献
373.
基于神经网络的煤与瓦斯突出预测模型 总被引:8,自引:1,他引:7
吴强 《中国安全科学学报》2001,11(4):69-72
在全面分析了煤与瓦斯突出影响因素的基础上 ,提出了煤与瓦斯突出预测的人工神经网络模型。介绍了突出特征指标的选取及表示方法与推理过程。实例分析表明 ,模型精度很高 ,可用于工作面煤与瓦斯突出预测 ,并分别给出图 2 ,表 3,文献 5 相似文献
374.
重金属化学活性评估方法准确性质疑--以煤矸石样品为例 总被引:5,自引:0,他引:5
重金属元素化学活性的大小是决定它们环境行为最主要的因素之一,我们曾分别用总量法,实验模拟法,环境地球化学法和化学形态分析法对煤矸石样品所含的重金属元素进行过环境影响分析,试图了解自然风化条件下这些有害元素潜在的生态环境效应,结果发现重金属元素的化学活性除了与它们在样品中含量的高低,赋存状态和化学形态等因素有关外,更主要地是取决于样品基质的组成和结构,由于大量有机质的络合和风化过程中生成的铁的胶体的吸附,从煤矸石释放出的重金属元素的化学活性受到明显限制,它们对环境的污染可能仅限于煤矸石堆周围有限的范围。 相似文献
375.
Tian HZ Zhao D He MC Wang Y Cheng K 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1613-1619
A multiple-year inventory of atmospheric antimony (Sb) emissions from coal combustion in China for the period of 1980-2007 has been calculated for the first time. Specifically, the emission inventories of Sb from 30 provinces and 4 economic sectors (thermal power, industry, residential use, and others) are evaluated and analyzed in detail. It shows that the total Sb emissions released from coal combustion in China have increased from 133.19 t in 1980 to 546.67 t in 2007, at an annually average growth rate of 5.4%. The antimony emissions are largely emitted by industrial sector and thermal power generation sector, contributing 53.6% and 26.9% of the totals, respectively. At provincial level, the distribution of Sb emissions shows significant variation. Between 2005 and 2007, provinces always rank at the top five largest Sb emissions are: Guizhou, Hunan, Hebei, Shandong, and Anhui. 相似文献
376.
377.
In order to study the influences of coal dust components on the explosibility of hybrid mixture of methane and coal dust, four kinds of coal dust with different components were selected in this study. Using the standard 20 L sphere, the maximum explosion pressure, explosion index and lower explosion limits of methane/coal dust mixtures were measured. The results show that the addition of methane to different kinds of coal dust can all clearly increase their maximum explosion pressure and explosion index and decrease their minimum explosion concentration. However, the increase in the maximum explosion pressure and explosion index is more significant for coal dust with lower volatile content, while the decrease in the minimum explosion concentration is more significant for coal dust with higher volatile content. It is concluded that the influence of methane on the explosion severity is more pronounced for coal dust with lower volatile content, but on ignition sensitivity it is more pronounced for coal dust with higher volatile content. Bartknecht model for predicting the lower explosion limits of methane/coal dust mixture has better applicability than Le Chatelier model and Jiang model. Especially, it is more suitable for hybrid mixtures of methane and high volatile coal dust. 相似文献
378.
In underground coal mining, methane explosions often can cause tremendous disasters. In the meantime, carbon monoxide (CO), generated during the process of coal oxidation, may appear in the air. Therefore, the explosion characteristics of the mixture of CH4 and CO must be investigated to prevent gas explosion accidents in coal mines. We conducted experiments by using a 20-L nearly spherical gas explosion testing device. The software FLACS was used to simulate the explosion of the mixture of CH4 and CO at various mixing concentrations, and the simulation results corresponded to experimental results. With the increase of CO concentration, both upper and lower explosive limits of CH4 decreased. On the whole, the explosion characteristic parameters of CH4 and the mixture are similar. When CH4 concentration was below the stoichiometric concentration, the addition of CO could promote the intensity of gas explosion; oppositely, excessive CO would inhibit the gas explosion reaction. The inhibitory effects become more significant as the concentration of CH4 increases. 相似文献
379.
380.
ABSTRACTAn efficient coal de-capacity quota allocation scheme is key for accelerating China’s coal supply-side structure reform. This paper allocates the coal de-capacity quota from the perspective of efficiency to seek the optimal capacity allocation in each Chinese province. First, we estimate the coal capacity of 24 coal-producing provinces based on boundary production function model. According to the actual coal overcapacity in each province, we initially allocate the coal de-capacity quota of reducing 0.8 billion tons among them. Then, we optimize the initial allocation plan by using the zero-sum gains data envelopment model (ZSG-DEA) considering backward coal capacity, coal economic output, and coal resource endowment of each province. The results indicate that: First, there is coal overcapacity all over China, and there are obvious differences among the provinces. Second, the optimal allocation results show that the large coal producing provinces, including Shanxi, Inter Mongolia, Shaanxi, etc., need to undertake most of the coal de-capacity tasks, while the old coal producing provinces in northeast and west China should undertake a heavier burden of coal de-capacity. Third, the “one-size fits-all” approach burdens the small coal producing provinces with reducing coal capacity, leading to a general low enthusiasm for coal de-capacity in these regions. 相似文献