全文获取类型
收费全文 | 4106篇 |
免费 | 395篇 |
国内免费 | 2232篇 |
专业分类
安全科学 | 160篇 |
废物处理 | 132篇 |
环保管理 | 313篇 |
综合类 | 3660篇 |
基础理论 | 1247篇 |
污染及防治 | 649篇 |
评价与监测 | 411篇 |
社会与环境 | 132篇 |
灾害及防治 | 29篇 |
出版年
2024年 | 38篇 |
2023年 | 132篇 |
2022年 | 201篇 |
2021年 | 209篇 |
2020年 | 211篇 |
2019年 | 206篇 |
2018年 | 220篇 |
2017年 | 243篇 |
2016年 | 276篇 |
2015年 | 358篇 |
2014年 | 356篇 |
2013年 | 585篇 |
2012年 | 437篇 |
2011年 | 394篇 |
2010年 | 334篇 |
2009年 | 334篇 |
2008年 | 321篇 |
2007年 | 330篇 |
2006年 | 317篇 |
2005年 | 209篇 |
2004年 | 186篇 |
2003年 | 158篇 |
2002年 | 116篇 |
2001年 | 107篇 |
2000年 | 69篇 |
1999年 | 67篇 |
1998年 | 58篇 |
1997年 | 47篇 |
1996年 | 51篇 |
1995年 | 37篇 |
1994年 | 21篇 |
1993年 | 19篇 |
1992年 | 24篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 3篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有6733条查询结果,搜索用时 31 毫秒
751.
印染污泥焚烧烟气污染控制案例分析 总被引:1,自引:0,他引:1
以广东省某两家印染厂的印染污泥焚烧项目为主要研究对象,从污泥处理技术路线、焚烧设备及烟气处理流程等各方面入手,对各厂印染污泥与煤混烧烟气中颗粒物、NOx、SO2、酸性气体(HF、HCl)和重金属等污染物的进行采样分析,并对各厂现有烟气污染物控制设施的运行效果进行调研,结果表明,布袋除尘的效果较为理想,除尘效率可达99%以上;使用印染废水作为吸收液的湿法脱硫技术对SO2及酸性气体的去除效果不理想;SNCR对NOx具有一定的去除效果,是一种较为经济、高效的脱硝技术;焚烧后,大部分重金属最终以飞灰的形式被除尘器去除,但仍有部分重金属如Hg在出口烟气中的浓度仍然很高,需要采取必要的措施控制烟气中的重金属. 此外,基于印染污泥焚烧实例分析,提出适于印染污泥与煤混烧烟气处理工艺流程. 相似文献
752.
The hypotheses on the de novo syntheses of polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo‐p‐dioxins (PCDDs), based on known literature, are presented. Polychlorinated benzenes and polychlorinated phenols are probably key intermediates. In the present article, hypotheses that may account for the presence of polychlorinated dibenzofurans (PCDFs) and dibenzo‐p‐dioxins (PCDDs) in the effluents from municipal and industrial incinerators are put forward. These hypotheses are based on the previously surveyed literature (Ref. 203–206) and experimental results on laboratory scale and thermodynamic calculations are considered. The interconnections of various reaction steps are speculative and no technological information was added to account for conditions in real incinerators. Conclusion of the discussions on the related subject matter, presented in the Parts I‐IV (Ref. 203–206), are also described in this paper. 相似文献
753.
An anayltical procedure based on a sequential extraction scheme is applied to samples of suspended particulates from an urban area of Barcelona. This area presents high levels of air pollution owing to automotive emissions and industrial activity. The procedure allows the partitioning of particulate trace metals into four fractions: soluble and exchangeable, bound to carbonates and iron‐manganese oxides, bound to organic matter and residual. In this work, the chemical associations of Fe, Pb, Cu, Mn, Cr and Cd have been investigated. In the analysed samples, only the cadmium is predominantly in the first fraction whereas the other metals are largely associated to carbonates and Fe‐Mn oxides. 相似文献
754.
Surficial sediment samples were wet digested (HNO3‐HCI‐HF) and analysed by atomic absorption spectroscopy. The background values in the area, and the Pollution Index Load in the sampling points were calculated. Metal inputs of continental origin are specially important in Deva, Oria and Urola river mouths. 相似文献
755.
Biotransformation rates of xenobiotic compounds in relation to enzymes activities: A critical review
Many biotransformation reactions and many activities of enzymes involved in the biotransformation of xenobiotics in fish have been described. Therefore, the prediction of biotransformation of (other) xenobiotics through literature data seems to be possible. However, very few data allow correlation of in vitro enzyme activities with in vivo biotransformation rates. This is mainly due to a lack of quantitative data. Suggestions are made for future research, which may help to relate enzyme activities and biotransformation in fish. 相似文献
756.
Gram negative bacteria classified as Alcaligenes eutrophus and carrying large resistance plasmids (generally two) were found in various industrial sites highly contaminated by heavy metals (Zn++, Cu++, Co++,...). These strains were detected by DNA hybridization with a probe made with a 9kb fragment (ccz+ fragment) encoding for resistances to Cd++, Co++ and Zn++, and cloned from plasmid pMOL30. This plasmid was isolated from the representative strain A. eutrophus CH34 which harbours the plasmids pMOL30 (240 kb) and pMOL28 (165 kb). Phenotypes related to pMOL28 and pMOL30 include the tolerance to Cd++, Co++, Cr04 =, Cu++, Hg++, Ni++, Pb++ and Zn++. The described genetic properties of these plasmids refer to some cloned or mapped functions and to some plasmid rearrangements. Plasmid pMOL85 (250 kb) which is related to pMOL30 was also described. Its host (A. eutrophus DS185) was isolated from a zinc desert. pMOL85 can efficiently self transfer in plasmidfree derivatives. 相似文献
757.
The levels of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and Hg are estimated by atomic absorption in the muscle of six commercial species of fish belonging to five freshwater lakes of Pakistan. The species included Mastacembelus armatus, Tor putitura, Mystus seenghala, Wallago attu, Catla catla and Labeo rohita. The fish were procured in comparable weight ranges so that a viable comparison of trace metal content could be effected. As, Fe, Pb, Zn and Hg showed elevated levels of 0.006–6.967, 0.933–6.133, 0.060–4.108, 0.978–5.363 and 0.030–3.211 μg/g, wet weight. The relevant statistical parameters, such as standard deviation, standard error, skewness and its t‐value are also reported for establishing the randomness of the distribution in relation to the corresponding data of freshwater lakes of the world and examined in view of species‐specificity and origin. 相似文献
758.
A receptor modeling approach has been applied to identify and apportion sources of airborne particulate matter in Thessaloniki, Greece. The absolute principal component analysis source apportionment technique used, provided quantitative information regarding both source particle characteristics and impacts. The analysis identified four major sources of heavy metals within total suspended particles (TSP) in the centre of the city: oil burning, pyrometallurgical non‐ferrous metal processes, motor vehicles and soil resuspension. Their contributions to TSP estimated by regression on absolute principal component scores (APCS) were 12%, 8%, 5% and 4%, respectively. A similar analysis conducted for a sampling site close to the industrial area identified five major sources: oil burning, industrial Cr source, soil resuspension, pyrometallurgical non‐ferrous metal processes and motor vehicles with contributions 20%, 15%, 9%, 8% and 4%, respectively. 相似文献
759.
This review describes the toxic effects of agrochemicals on earthworms. Carbamates are described as extremely toxic to earthworms in comparison to organophosphorus insecticides. Some pesticides have drastic effect on the nervous system of the earthworm. Earthworm can accumulate heavy metals from the soil in higher levels than any other animal. Mercury is twenty times more toxic than chromium. 相似文献
760.
以城市污泥为主要原料制备了污泥基活性炭(SAC),考察了其对重金属离子的吸附去除效能和吸附动力学规律.并选择了2种商品活性炭(煤质炭,MAC和椰壳炭,YAC)作为对比,以初始浓度为50mg/L的Cu(II),Pb(II),Cd(II),Cr(VI)4种重金属离子为去除对象,分别进行了3种活性炭的表面理化性质分析及其对4种重金属离子的吸附试验.结果表明,SAC的比表面积和微孔容积仅为YAC和MAC的1/3~1/2,吸附速率也相对较慢,但其对Cu(II),Pb(II),Cr(VI),Cd(II)的平衡吸附量却远大于2种商品活性炭,分别为9.9,8.9,8.2,5.4mg/g,说明SAC表面的高酸性基团含量对重金属离子的吸附起到了关键作用;Langmuir与Freundlich吸附等温模型均能较好地拟合SAC对Cu(II)和Pb(II)的吸附,SAC对Cr(VI)的吸附过程更符合Langmuir模型,而SAC对于Cd(II)的吸附过程用Langmuir与Freundlich两个模型均不能较好地拟合,说明SAC表面缺少能够与Cd(II)发生反应的结合位点. 相似文献