全文获取类型
收费全文 | 895篇 |
免费 | 51篇 |
国内免费 | 34篇 |
专业分类
安全科学 | 118篇 |
废物处理 | 6篇 |
环保管理 | 53篇 |
综合类 | 720篇 |
基础理论 | 16篇 |
污染及防治 | 23篇 |
评价与监测 | 8篇 |
社会与环境 | 6篇 |
灾害及防治 | 30篇 |
出版年
2024年 | 2篇 |
2023年 | 10篇 |
2022年 | 10篇 |
2021年 | 20篇 |
2020年 | 17篇 |
2019年 | 15篇 |
2018年 | 9篇 |
2017年 | 10篇 |
2016年 | 16篇 |
2015年 | 17篇 |
2014年 | 564篇 |
2013年 | 14篇 |
2012年 | 18篇 |
2011年 | 21篇 |
2010年 | 18篇 |
2009年 | 22篇 |
2008年 | 25篇 |
2007年 | 30篇 |
2006年 | 15篇 |
2005年 | 21篇 |
2004年 | 13篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 11篇 |
1997年 | 7篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 5篇 |
排序方式: 共有980条查询结果,搜索用时 156 毫秒
31.
32.
33.
34.
A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3^-, NH4^+, SO4^2-, and SOA were calculated in the fine particle size range (〈2.5 μm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign (IMC). Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio. 相似文献
35.
Tao Zhang Qiucheng Li Lili Ding Hongqiang Ren Ke Xu Yonggang Wu Dong Sheng 《环境科学学报(英文版)》2011,23(6):881-890
Chemical precipitation to form magnesium ammonium phosphate (MAP) is an effective technology for recovering ammonium
nitrogen (NH4
+-N). In the present research, we investigated the thermodynamic modeling of the PHREEQC program for NH4
+-N
recovery to evaluate the effect of reaction factors on MAP precipitation. The case study of NH4
+-N recovery from coking wastewater
was conducted to provide a comparison. Response surface methodology (RSM) was applied to assist in understanding the relative
significance of reaction factors and the interactive effects of solution conditions. Thermodynamic modeling indicated that the saturation
index (SI) of MAP followed a polynomial function of pH. The SI of MAP increased logarithmically with the Mg2+/NH4
+ molar ratio
(Mg/N) and the initial NH4
+-N concentration (CN), respectively, while it decreased with an increase in Ca2+/NH4
+ and CO3
2??/NH4
+
molar ratios (Ca/N and CO3
2??/N), respectively. The trends for NH4
+-N removal at different pH and Mg/N levels were similar to the
thermodynamic modeling predictions. The RSM analysis indicated that the factors including pH, Mg/N, CN, Ca/N, (Mg/N) (CO3
2??/N),
(pH)2, (Mg/N)2, and (CN)2 were significant. Response surface plots were useful for understanding the interaction effects on NH4
+-N
recovery. 相似文献
36.
The study investigated the effects of ethanol on the adsorption properties of bentonite and kaolin for benzene and toluene removal. 相似文献
37.
为评估工业水污染物减排潜力、探究污染防治技术模拟在污染物总量控制、污染物排放限值等环境管理中的应用,按照"原料-工艺-技术-产品"的耦合关系建立了"工业污染物减排潜力分析及环境管理"模型,集成自下而上建模和情景分析等方法在我国造纸行业进行案例研究.结果表明,在政策组合情景下,废水、COD、氨氮在2015年的减排潜力分别为7×108t、39×104t、0.3×104t,2020年分别为13.8×108t、56×104t和0.5×104t;2010~2020年期间加强末端治理仍然是主要减排途径,但2015~2020年间行业结构调整的作用将逐渐提升,并使行业产污水平在2015年和2020年基本达到国内或国际先进水平,废水和氨氮指标在2015年和2020年基本满足排放标准,但COD难以达标. 相似文献
38.
39.