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二氧化硫和氮氧化物是电厂产生的主要大气污染物,研究焦点越来越集中在在一个反应器内实现同时脱硫脱硝。实验以H2O溶液作为吸收液,在自制的鼓泡反应器内,对模拟烟气进行同时脱硫脱硝的实验研究,实验结果表明:H2O浓度、反应温度、NO浓度、SO2浓度、烟气流量对脱除率影响显著,pH、氧含量对脱硝率影响不大。在整个实验范围内脱硫效率总是保持在98.5%以上,脱硝效率最高达到67.4%。 相似文献
806.
环渤海地区的经济增长与工业废气污染问题研究 总被引:3,自引:0,他引:3
本文利用1981-2005年环渤海三省二市工业废气排放量、人均实际GDP以及第二产业占GDP的比重、外商直接投资占GDP的比重等两个污染控制变量的年度数据,建立panal data模型,通过实证分析验证了环境库兹涅茨曲线是否存在以及什么因素影响环境库兹涅茨曲线的形状.实证结果表明,环渤海地区工业废气排放量与人均GDP之间呈现整体向上倾斜的倒"N"形的曲线特征,随着经济发展水平的提高、经济规模的扩大和重化工业化进程的推进,环渤海地区的工业废气排放污染呈现出持续恶化的趋势:恶化速度可能存在一个先相对减缓、后加速、然后相对减缓的过程,这不同于传统的环境库兹涅茨饲"U"假说;就目前的经济发展阶段来说,环渤海地区尚未达到环境压力得到改善的转折点:产业结构的转换对工业废气污染产生显著影响;外商直接投资没有显著地加剧环渤海地区的工业废气污染,FDI导致的污染产业国际转移现象没有在这一地区发生;不同省市的个体影响具有一定的差异;工业废气排放量与人均GDP及其二次项、三次项之间存在面板协整关系,实证结果是稳健可信的. 相似文献
807.
Terrestrial carbon storage is influenced by a number of environmental factors, among which topographic and geomorphological
features are of special significance. This study was designed to examine the relationships of soil organic carbon (SOC) density
to various terrain parameters and watershed characteristics across Louisiana, USA. A polygon data set of 484 watersheds and
12 river drainage basins for Louisiana was used to form the landscape units. SOC densities were calculated for each soil map
unit using the State Soil Geographic (STATSGO) database. Average drainage densities and average slopes at watershed and basin
scales were quantified with the 1:24 K Digital Elevation Models (DEM) data, and the Louisiana hydrographic water features.
Correlation and regression analyses were performed to determine relationships among drainage density, slope, elevation, and
SOC. The study found an average watershed drainage density of 1.6 km/km2 and an average watershed slope of 2.9 degrees in Louisiana. The results revealed that SOC density at both watershed and basin
scales was closely related to drainage density, slope, and elevation. SOC density was positively correlated with watershed
drainage density, but negatively correlated with watershed slope gradient and elevation. Regression models were developed
for predicting SOC density at watershed and basin scales, obtaining regression coefficients (r
2) ranging from 0.43 to 0.83. The study showed that estimation of SOC at watershed and drainage basin scales combining DEM
data can be a feasible approach to improve the understanding of the relationships among SOC, topographic, and geomorphological
features. 相似文献
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Ground-level ozone in the Pearl River Delta and the roles of VOC and NO(x) in its production 总被引:3,自引:0,他引:3
Shao M Zhang Y Zeng L Tang X Zhang J Zhong L Wang B 《Journal of environmental management》2009,90(1):512-518
In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) emission controls. Nonetheless, ambient NO(2) levels in the Pearl River Delta remained high. The regional average concentrations of volatile organic compounds (VOCs) were 290 ppbC in summer and 190 ppbC in autumn. Local emissions and long-distance transportation of pollutants play important roles in the regional distribution of VOCs. Ambient O(3) production is significant in urban areas and also downwind of cities. The relative incremental reactivities (RIRs), determined by an observation-based model, showed that ground-level ozone formation in the Guangzhou urban area is generally limited by the concentrations of VOCs, but there are also measurable impacts of NO(x). 相似文献