全文获取类型
收费全文 | 392篇 |
免费 | 18篇 |
国内免费 | 84篇 |
专业分类
安全科学 | 12篇 |
废物处理 | 10篇 |
环保管理 | 37篇 |
综合类 | 243篇 |
基础理论 | 23篇 |
污染及防治 | 83篇 |
评价与监测 | 72篇 |
社会与环境 | 14篇 |
出版年
2023年 | 12篇 |
2022年 | 13篇 |
2021年 | 10篇 |
2020年 | 19篇 |
2019年 | 17篇 |
2018年 | 16篇 |
2017年 | 20篇 |
2016年 | 21篇 |
2015年 | 21篇 |
2014年 | 27篇 |
2013年 | 19篇 |
2012年 | 33篇 |
2011年 | 38篇 |
2010年 | 16篇 |
2009年 | 31篇 |
2008年 | 29篇 |
2007年 | 17篇 |
2006年 | 16篇 |
2005年 | 16篇 |
2004年 | 8篇 |
2003年 | 16篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 9篇 |
1998年 | 8篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 3篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1982年 | 1篇 |
排序方式: 共有494条查询结果,搜索用时 15 毫秒
221.
222.
Selective catalytic reduction (SCR) denitration may increase the emission of NH4+ and NH3. The removal and transformation characteristics of ammonium sulfate aerosols and ammonia slip during the wet flue gas desulfurization (WFGD) process, as well as the effect of desulfurization parameters, were investigated in an experimental system equipped with a simulated SCR flue gas generation system and a limestone-based WFGD system. The results indicate that the ammonium sulfate aerosols and ammonia slip in the flue gas from SCR can be partly removed by slurry scrubbing, while the entrainment and evaporation of desulfurization slurry with accumulated NH4+ will generate new ammonium-containing particles and gaseous ammonia. The ammonium-containing particles formed by desulfurization are not only derived from the entrainment of slurry droplets, but also from the re-condensation of gaseous ammonia generated by slurry evaporation. Therefore, even if the concentration of NH4+ in the desulfurization slurry is quite low, a high level of NH4+ was still contained in the fine particles at the outlet of the scrubber. When the accumulated NH4+ in the desulfurization slurry was high enough, the WFGD system promoted the conversion of NH3 to NH4+ and increased the additional emission of primary NH4+ aerosols. With the decline of the liquid/gas ratio and flue gas temperature, the removal efficiency of ammonia sulfate aerosols increased, and the NH4+ emitted from entrainment and evaporation of the desulfurization slurry decreased. In addition, the volatile ammonia concentration after the WFGD system was reduced with the decrease of the NH4+ concentration and pH values of the slurry. 相似文献
223.
Xi Cheng Hong Li Yujie Zhang Yuping Li Weiqi Zhang Xuezhong Wang Fang Bi Hao Zhang Jian Gao Fahe Chai Xiaoxiu Lun Yizhen Chen Jian Gao Junyi Lv 《环境科学学报(英文版)》2018,30(9):150-167
Continuous observation of isoprene, α-pinene and β-pinene was carried out in a typical urban area of Beijing from March 2014 to February 2015, using an AirmoV OC online analyzer. Based on the analysis of the ambient level and variation characteristics of isoprene, α-pinene and β-pinene, the chemical reactivity was studied, and their sources were identified. Results showed that the concentrations of isoprene, α-pinene and β-pinene in the urban area of Beijing were lower than those in richly vegetated areas; the concentrations of isoprene were at a moderate level compared with those of previous studies of Beijing. Concentrations of isoprene, α-pinene and β-pinene showed different seasonal, monthly, daily and diurnal variations, and all of the three species showed higher level at night than those in the daytime as a whole, the variations of isoprene, α-pinene and β-pinene mainly influenced by emission of sources, photochemical reaction, and meteorological parameters. Isoprene was the largest contributor to the total OFP values than α-pinene and β-pinene. α-Pinene was the largest contributor to the total SOAFP values than isoprene and β-pinene in autumn, while isoprene was the largest one in other seasons. Isoprene, α-pinene and β-pinene were derived mainly from biological sources; and α-pinene level were also affected by industrial sources. To reduce the concentrations of isoprene, α-pinene and β-pinene, it is necessary to scientifically select urban green plant species, and more strict control measures should be taken to reduce the emission of α-pinene from industrial sources, such as artificial flavors and resins synthesis processes. 相似文献
224.
O.H. Manscher N.Z. Heidam J. Vikelse P. Nielsen P. Blinksbjerg H. Madsen L. Pallesen T.O. Tiernan 《Chemosphere》1990,20(10-12)
During the last two years an extensive series of dioxin measurements has been conducted on Danish municipal and hospital solid waste incinerators. The study was directed toward finding the total annual dioxin emissions from MSWI in Denmark, now estimated to be 3 kg. of dioxines and furanes. This sum is equivalent to 50 g. of 2,3,7,8-TCDD according to the Nordic Equivalents. Measurements were carried out according to a statistical design following a plan of pre-randomized sampling. This procedure allowed causal interpretation of the correlations found between the dioxin emissions and certain operating parameters. The statistical model obtained describes the emissions by variations between incinerators, by variation in time, and by changes in the load, the excess air and the HCl concentration in the flue gas. 相似文献
225.
汽车排放标准与控制技术的发展 总被引:3,自引:0,他引:3
介绍汽车排放标准发展趋势,分析实现排放控制指标的相关支撑技术,从中可以看到排放问题在很长一段时间内,仍将主导汽车发动机的研制与开发,国内汽车排放控制尚处于起步阶段,与国际接轨还有很长的路要走。 相似文献
226.
AIJ试点项目评估方法研究——商丘热电厂热电联产试点项目 总被引:3,自引:0,他引:3
在 AIJ评估中 ,主要的问题包括项目边界 ,基准线的选择 ,温室气体减排量的计算 ,减排增量成本的计算等。本文主要结合商丘热电厂 AIJ项目的具体案例对 AIJ项目评估中存在的这些问题进行研究。该项目的供热基准线是分散式小锅炉 ,供电基准线是河南省电网。商丘热电厂的供热和供电煤耗明显比基准线低 ,从而具有明显的节能和温室气体减排效应。但同时此项目的供热供电成本比基准线高 ,具有减排增量成本 相似文献
227.
江苏省温室气体排放研究 总被引:3,自引:0,他引:3
根据IPCC Guidelines(1995)提供的方法,对1990年江苏省温室气体排放清单统计计算,分析该地区能源、工业及农业CO_2、CH_4等温室气体排放量的状况.江苏省年人均排放CO_2为1970kg、CH_4为22.65kg、N_2O为0.11kg,与全国平均水平接近、为全球均值一半.能源消耗是江苏省各项活动中CO_2的排放主要因素,占总排放量的91.6%;CH_4的排放主要来自水稻田,占总排放量的44.1%. 相似文献
228.
制定污水中控制项目地方排放标准的几点考虑 总被引:1,自引:0,他引:1
以新疆石河子市为例,阐述了实行水污染物排放许可证制度,制定污水中控制项目的地方排放标准时应考虑的几点原则和确定标准值的思路. 相似文献
229.
现代科学技术发展的一个显著特点是多学科综合发展,物理光进学与化学分析相结合所产生的现代物理化学分析新技术──发光光谱分析在环境监测领域得到了广泛的应用。本文针对这一新技术的原理和特点作了简要介绍,并对近年来在环境监测中的应用作了较详细的介绍和评述。 相似文献
230.
抚顺市大气颗粒物主要排放源的成分谱研究 总被引:4,自引:0,他引:4
抚顺市的5种大气颗粒物主要排放源中土壤风沙尘的特征元素为K,钢铁尘的特征元素为Fe,建筑水泥尘的特征元素为Ca,煤烟尘的特征元素为Ti。土壤风沙尘和扬尘中含量最高的元素为Al,煤烟尘中含量最高的元素为EC,钢铁尘中含量最高的元素为Fe,建筑水泥尘中含量最高的元素为Ca。 相似文献