全文获取类型
收费全文 | 2927篇 |
免费 | 469篇 |
国内免费 | 1466篇 |
专业分类
安全科学 | 232篇 |
废物处理 | 132篇 |
环保管理 | 397篇 |
综合类 | 2921篇 |
基础理论 | 298篇 |
污染及防治 | 319篇 |
评价与监测 | 321篇 |
社会与环境 | 226篇 |
灾害及防治 | 16篇 |
出版年
2024年 | 41篇 |
2023年 | 139篇 |
2022年 | 202篇 |
2021年 | 251篇 |
2020年 | 228篇 |
2019年 | 210篇 |
2018年 | 204篇 |
2017年 | 239篇 |
2016年 | 260篇 |
2015年 | 274篇 |
2014年 | 242篇 |
2013年 | 307篇 |
2012年 | 320篇 |
2011年 | 342篇 |
2010年 | 205篇 |
2009年 | 177篇 |
2008年 | 123篇 |
2007年 | 147篇 |
2006年 | 156篇 |
2005年 | 111篇 |
2004年 | 82篇 |
2003年 | 112篇 |
2002年 | 68篇 |
2001年 | 86篇 |
2000年 | 69篇 |
1999年 | 67篇 |
1998年 | 34篇 |
1997年 | 36篇 |
1996年 | 30篇 |
1995年 | 25篇 |
1994年 | 20篇 |
1993年 | 13篇 |
1992年 | 9篇 |
1991年 | 9篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1972年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有4862条查询结果,搜索用时 15 毫秒
71.
为了解污水处理过程中各处理单元NH3的排放特征,采集石家庄某制药企业各污水处理单元以及经过废气治理后排放的样品,计算各采样点NH3浓度及排放量。结果表明:各污水处理单元中,水解酸化池NH3浓度和单位体积污水NH3排放量均为最高,分别为62.89和3 360 mg∕m 3。各污水处理单元NH3总排放量为0.97 kg∕h,单位体积污水NH3排放量为9 312 mg∕m 3;经废气治理后,排入环境的NH3为0.25 kg∕h,单位体积污水NH3排放量为2 400 mg∕m 3,去除率为74.2%,经治理后NH3排放量明显降低。南区、北区废气治理采用碱洗+氧化+水洗工艺,NH3去除率分别为93.3%和83.1%;生物区废气治理采用生物滴滤床工艺,NH3去除率为39.1%,碱洗+氧化+水洗工艺对NH3的去除效果好于生物滴滤床工艺。 相似文献
72.
73.
74.
Vahab Vaezzadeh Aileen Tan Shau-Hwai Zelina Zaiton Ibrahim Shuhaimi Mustafa Mehrzad Keshavarzifard 《Environmental Forensics》2015,16(2):135-142
This article is the most recent report of polycyclic aromatic hydrocarbons (PAHs) in the Muar River and Pulau Merambong, Peninsular Malaysia. A total of 16 priority pollutant PAHs in addition to methylphenanthrene among alkylated PAHs were analyzed in surface sediments during May 2013. Total PAHs ranged from 212 to 440 and 151 to 412 ng g?1 dw in sediments from the Muar River and the Pulau Merambong, respectively. The Muar River showed an increasing trend of PAH concentrations, while no previous data exist for the Pulau Merambong. Generally, mixed petrogenic and pyrogenic sources of PAHs with predominance of the latter were detected in the study area. Effective management of oil pollution has caused a drastic decrease in petrogenic sources of PAHs. 相似文献
75.
可交易排污许可证在传统的排污许可证基础上,引入市场机制。不但对企业选择污染控制手段赋予更大的灵活性,而且可以大大节约水污染控制费用、剌激企业开发并建设更加经济有效的污染控制技术。国外十多年的研究和实践证明可交易排污许可证是一种经济而有效的环境管理手段。水污染排放许可证制度在我国的应用已有一定基础。在条件具备的地区可以引进可交易水污染物排放许可证制度,本文回顾了“可交易水污染许可证制度”的理论分析和国外实践,进而探讨在中国的应用前景 相似文献
76.
随着我国对VOCs监测控制的持续推进,VOCs标准气体的配套应用及其管理思路也面临着新要求和挑战。本文通过梳理我国VOCs类标准气体对涉VOCs企业污染物监测和管理支撑的现状,指出了VOCs监测管理中对标准气体的应用要求尚待细化、已有VOCs标准气体应用不够充分、VOCs标准气体对排放标准实施的精准支撑作用不足等问题。在探究现状与问题的基础上,提出进一步细化VOCs排放监测对标准气体应用要求、加强企业自行监测中VOCs标准气体的应用指导、加强短缺标准气体的研制与应用的建议。 相似文献
77.
The Ria Formosa lagoon, Portugal, receives organic matter from many natural and anthropogenic sources. This paper presents an overview of the contribution these sources made through the use of lipid biomarkers. Sixty-one surface sediment samples were collected and analysed for a range of lipids. Sewage materials were confined to regions within 2 km of discharge points; phytoplankton biomarkers (sterols and fatty acids) suggest production was greatest in the inner parts of the lagoon that also have greatest inorganic nutrient enrichment; terrestrial organic matter was present in relatively low concentrations as shown by both sterol and fatty alcohols; bacteria were widespread although the Sulphate Reducing Bacteria (SRBs, shown by the presence of 3-OH fatty acids) were located near but not adjacent to sewage discharge points. 相似文献
78.
An automated method for the indirect determination of fluoride by inductively coupled plasma atomic emission spectrometry using discontinuous-flow analysis has been developed. A modified flow injection analysis system was used for sample preparation. The method is based on the determination of excess cerium(III) ion after precipitation of CeF3. Separation of the precipitate is performed online on a syringe membrane filter that is cleaned each analysis cycle by 1 M nitric acid, ensuring a long life-time for the filter. As a result of the short reaction time, a detection limit of 9.5 mg L?1 was obtained. The precision (RSD) of the proposed method is 1.02% at fluoride concentration of 28 mg L?1. The applicability of the technique for groundwater monitoring of fluoride-contaminated area is demonstrated. 相似文献
79.
Kebede Nigussie Mekonnen Bhagwan Singh Chandravanshi Mesfin Redi-Abshiro Robert Ian McCrindle 《毒物与环境化学》2013,95(10):1501-1515
For the determination of 15 potentially toxic elements (V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Se, Ag, Cd, Sn, Hg, and Pb) in plant and sediment samples of the Akaki River, Ethiopia, inductively coupled plasma–mass spectrometry, inductively coupled plasma–optical emission spectrometry, and a RA-915+ mercury analyzer were applied. Sediment and plant samples were mineralized using a closed-vessel microwave-assisted digestion system. The elemental concentrations varied considerably in plant and sediment samples. The minimum concentration was observed for known toxic elements (As, Hg, and Cd) while the highest concentration was observed for the elements of relatively low toxicity Zn, Mn, and Fe. The concentration of Cr, Fe, Pb, Zn, and As in Swiss chard surpassed the maximum permissible levels at specific sites. At some of the sites, the sediment quality guidelines are surpassed for Cu, Zn, and Pb. 相似文献
80.
There exist a vast variety of data sources, either manual sources or computerized databases in the field of environmental chemicals. To facilitate the access and to retrieve the information wanted efficiently, we built up two “databanks of data sources”, one called “Databank of Manual Sources (DMAS)” and the other named “Databank of Databases (DADB)”. The set‐up of these databanks is explained and the load status statistics are shown. DMAS has 164 and DADB 106 hits. 相似文献