全文获取类型
收费全文 | 2610篇 |
免费 | 113篇 |
国内免费 | 748篇 |
专业分类
安全科学 | 142篇 |
废物处理 | 169篇 |
环保管理 | 215篇 |
综合类 | 1248篇 |
基础理论 | 444篇 |
环境理论 | 1篇 |
污染及防治 | 961篇 |
评价与监测 | 116篇 |
社会与环境 | 63篇 |
灾害及防治 | 112篇 |
出版年
2023年 | 36篇 |
2022年 | 115篇 |
2021年 | 107篇 |
2020年 | 71篇 |
2019年 | 83篇 |
2018年 | 76篇 |
2017年 | 116篇 |
2016年 | 137篇 |
2015年 | 130篇 |
2014年 | 212篇 |
2013年 | 260篇 |
2012年 | 240篇 |
2011年 | 243篇 |
2010年 | 187篇 |
2009年 | 178篇 |
2008年 | 177篇 |
2007年 | 148篇 |
2006年 | 146篇 |
2005年 | 109篇 |
2004年 | 80篇 |
2003年 | 88篇 |
2002年 | 70篇 |
2001年 | 53篇 |
2000年 | 53篇 |
1999年 | 57篇 |
1998年 | 50篇 |
1997年 | 52篇 |
1996年 | 31篇 |
1995年 | 32篇 |
1994年 | 27篇 |
1993年 | 19篇 |
1992年 | 23篇 |
1991年 | 12篇 |
1990年 | 18篇 |
1989年 | 13篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1958年 | 2篇 |
排序方式: 共有3471条查询结果,搜索用时 348 毫秒
181.
表面活性剂清洗处理重度石油污染土壤 总被引:5,自引:1,他引:4
为了优化表面活性剂清洗处理重度石油污染土壤的方法和具体洗脱条件参数,采集山东省东营市胜利油田污染土壤,研究了阴离子-非离子混合表面活性剂对该土壤中石油类污染物的去除效果。应用化学热洗原理,主要考查了表面活性剂配比、投加量、清洗温度及清洗助剂对去除效果的影响。实验得到的清洗处理最佳条件为:使用LAS与TX-100质量比为8∶2的组合表面活性剂,总表面活性剂浓度为3 g/L,助剂硅酸钠浓度为5 g/L,75℃条件下搅拌1 h。清洗后土壤含油量从20%下降到4.6%,去除率达到76.9%。废水回用实验表明,清洗处理的废水对土壤中石油烃类物质仍有一定的去除效果。废水回用比从30%到100%时,对土壤中石油烃的去除率都可达到55%以上。对废水进行二次回用时仍能去除18.8%的污染物。 相似文献
182.
采用模拟重金属废水的正交试验设计,进行赭石对模拟重金属废水的吸附效果研究,探讨pH、赭石加入量和振荡时间等影响因素对吸附效果的影响。结果表明,在一定pH、赭石加入量和振荡时间条件下,赭石对6种重金属(Pb、Cd、Mn、Zn、Cr和Ni)均有较好吸附效果,对Pb、Cd、Mn、Zn和Cr的最大吸附率可达100%,对Ni的吸附率达8963%。处理后废水中重金属达到污水排放标准。各影响因素对Mn、Zn和Cr吸附效率的影响大小表现为:pH>赭石加入量>振荡时间,Ni和Cd表现为:赭石加入量>pH>振荡时间,Pb表现为:pH>振荡时间>赭石加入量。赭石对废水中重金属吸附的最佳条件为赭石加入量40 g/L,pH 10~10.5,振荡时间2 h。 相似文献
183.
利用UVC去除低浓度苯的实验研究 总被引:3,自引:1,他引:2
探讨了不同实验参数对苯的UVC去除效果的影响,获得了苯的去除率与苯的初始浓度、气体流量、相对湿度和氧气含量等参数之间的关系。数据表明,在实验条件范围内,苯的去除率的倒数与苯初始浓度、气体流量之间为线性关系;苯的去除率随相对湿度的增加呈现先升高后缓慢降低的关系,最佳相对湿度值在30%~50%之间;苯的去除率随氧气量的增加而缓慢增加;波长为185+254 nm的UV与254 nm的UV相比净化效果更为理想。还分析了苯降解产生的中间产物,探讨了苯的降解机理。 相似文献
184.
185.
固定化假单胞菌降解油烟废气的研究 总被引:1,自引:0,他引:1
将从受油烟废气污染严重的土壤中分离筛选的具有较强降解油烟能力的假单胞菌利用活性炭为填料吸附固定后制成填料床生物反应器。实验考察了进气浓度、气体流量、气体停留时间、容积负荷等对油烟去除率的影响,初步研究了生物反应器的抗冲击能力。结果表明,活性炭填料对菌体具有良好的吸附能力,当油烟进气浓度小于100 mg/L,气体流速小于8 L/h,停留时间大于30 s,容积负荷为2.6~18.9 g油烟废气/(m3·h),生物反应器的降解效率可达到95%以上,且活性炭填料床反应器具有较强的抗冲击能力。 相似文献
186.
微电解-催化氧化法处理高浓度甲醇废水 总被引:6,自引:2,他引:4
采用微电解一催化氧化法处理某化工厂的高浓度甲醇生产废水。实验结果表明:在进水pH为2.0、铁炭质量比为2、微电解时间为14h、空气流量为500mL/min的条件下,废水经微电解处理后,出水COD由原来的约7000mg/L降至约1000mg/L,COD去除率达85%以上;在过滤后微电解出水COD约为950mg/L、微电解出水pH为6.5、空气流量为300mL/min、催化氧化时间为3h时的条件下,经催化氧化处理后,出水COD降至100mg/L以下,出水水质达到GB8978--1996《污水综合排放标准》的二级标准。 相似文献
187.
Uptake of organic contaminants by plant roots consists of two consecutive steps: sorption to plant roots and entrance into root xylem tissues through epidermal and endodermic membranes. Most research pertaining to phytoremediation assumed that sorption to plant roots is linear and non-competitive. A growing body of evidence, however, is suggesting that sorption to plant roots is nonlinear and competitive. The objective of this study was to examine the concentration effects of chemical constituents on the competitive sorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) to the roots of Typha latifolia. Competitive sorption was clearly demonstrated by the reduced sorption of TCE and PCE in bi-solute systems than in single-solute systems. Concentration is an important factor affecting the extent of competition. In bi-solute systems, the PCE/TCE ratio on root surface approximately reflected the contaminant footprints in solution. The result was attributed to limited high energetically favorable sorption sites on the root surface and similar sorption mechanisms of TCE and PCE. The results hold significant importance for the application of phytomonitoring of organic contaminant mixtures. 相似文献
188.
随着安全社区在我国推广工作的不断深入开展,与之相适应的科学方法的运用水平与有效性已经显得相对不足。由于安全社区建设和伤害预防工作涉及社会学、管理学、预防医学、安全科学、心理学等多个学科,其学科跨度及巨大复杂性,使得没有任何一个学科可以单独地应用完成,并且它具有许多不同于其他学科的特殊性,因此,关于安全社区建设过程中的科学方法研究十分必要。 相似文献
189.
Ecological risk assessment of open coal mine area 总被引:2,自引:0,他引:2
The coal mine areas in China have the serious conflicts between resources exploitation and ecology safety, therefore the coal mine ecological risk assessment is an important problem which relates to the sustainability of coal mines to regions and the whole country. In this study, open coal mine area serves as researching object, heavy metals, soil erosion and coast are screened out as risk resources, soil wireworm as the receiver of heavy metals risk, biotope ecosystem as the receiver of soil erosion and coast risk; ecological indexes are calculated with species background index, biological diversity index and natural degree index, ecological friability indexes are calculated with soil fertility index, plant coverage, plant species diversity index, soil wireworm index and maturity index, and the typical coal mine area assessment indexes system is established. In addition, the regional ecological risk assessment is conducted on the friable ecological system of Fuxin Haizhou open coal mine area. Examples are researched of Haizhou open coal mine, the coal mine risk distribution is established, and foundations are provided for the administrative decision-making. 相似文献
190.
Ma YG Cheng JP Jiao F Duo KX Rong Z Li M Wang WH 《Environmental monitoring and assessment》2008,146(1-3):127-138
Distribution and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in drinking water resources have been carried out for the first time in Henan Province, China. Water samples collected from four river systems and their tributaries, as well as groundwater resources, were analyzed according to EPA method 525.2. Total of 68 water samples were collected in 18 cities in Henan province in May, August and November, 2001. Concentrations of sum of 16 priority PAHs in water samples ranged from 15 to 844 ng/L with a mean value of 178 +/- 210 ng/L (n = 68). The spatial and temporal distribution of PAHs showed that the Huanghe and the Huaihe river systems had relatively higher concentrations of total PAHs. Higher concentrations of total PAHs were observed in August and November than in May, with respective mean values of 262, 232 and 33.6 ng/L. Ratios of Ant/(Ant + Phe) and Flur/(Flur + Pyr) were calculated to evaluate the possible sources of PAH contamination, which indicated that the coal combustion sources were the main contributors to PAHs in most drinking water resources. Some petrogenic (or pyrolytic) sources of PAHs were also found. The toxic equivalency factors (TEFs) were used to calculate benzo[a]pyrene equivalents (BaPE) for water samples. The average value of BaPE was 0.6 ng/L. The values in most stations were much lower than the guideline values in drinking water of Chinese Environmental Protection Agency (CEPA, 2.8 ng/L) and the US Environmental Protection Agency (US EPA, 200 ng/L). Overall, the drinking water resources in Henan province showed some carcinogenic potential. 相似文献