全文获取类型
收费全文 | 1624篇 |
免费 | 60篇 |
国内免费 | 608篇 |
专业分类
安全科学 | 132篇 |
废物处理 | 99篇 |
环保管理 | 128篇 |
综合类 | 894篇 |
基础理论 | 282篇 |
污染及防治 | 588篇 |
评价与监测 | 44篇 |
社会与环境 | 53篇 |
灾害及防治 | 72篇 |
出版年
2024年 | 1篇 |
2023年 | 25篇 |
2022年 | 71篇 |
2021年 | 68篇 |
2020年 | 47篇 |
2019年 | 32篇 |
2018年 | 52篇 |
2017年 | 76篇 |
2016年 | 76篇 |
2015年 | 66篇 |
2014年 | 129篇 |
2013年 | 150篇 |
2012年 | 162篇 |
2011年 | 120篇 |
2010年 | 121篇 |
2009年 | 114篇 |
2008年 | 124篇 |
2007年 | 105篇 |
2006年 | 89篇 |
2005年 | 76篇 |
2004年 | 34篇 |
2003年 | 62篇 |
2002年 | 57篇 |
2001年 | 47篇 |
2000年 | 45篇 |
1999年 | 61篇 |
1998年 | 51篇 |
1997年 | 41篇 |
1996年 | 39篇 |
1995年 | 37篇 |
1994年 | 24篇 |
1993年 | 26篇 |
1992年 | 20篇 |
1991年 | 15篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 8篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有2292条查询结果,搜索用时 562 毫秒
861.
改进碳纳米管/聚氨酯复合材料吸附硝基苯 总被引:1,自引:0,他引:1
以酸化碳纳米管(CNTs)强化聚氨酯泡沫(PUF),通过原位聚合法制备碳纳米管/聚氨酯复合材料(CPUF)。借助红外光谱(FT-IR)、扫描电镜(SEM)、热失重分析(TGA)和力学性能测试等方法研究和表征了CPUF复合材料的性能和结构。研究了用CPUF复合材料对人工模拟废水中硝基苯(NB)的吸附性能、影响因素及其再生后吸附效果。结果表明,CPUF复合材料对硝基苯具有较强的吸附能力,在p H=5.4、投加量为2 g/L、接触时间24 h的条件下,升高温度会降低CPUF复合材料的饱和吸附量,但会提高初始吸附速率,等温吸附过程符合Langmuir方程,属于单分子吸附。饱和后的复合材料可采用简单热再生,再生后对NB的吸附能力没有明显下降。 相似文献
862.
建立了电感耦合等离子体质谱(ICP-MS)法测定SCR脱硝尿素中Na、Mg、Al、P、K、Ca、Cr、Fe、Ni、Cu、Zn、Pb等12种微量元素的分析方法.通过向碰撞/反应池(CRC)系统中引入氦气消除多原子离子质谱干扰,采用混合内标元素45Sc、89Y、209Bi消除基体效应.结果表明,各元素在一定范围内线性关系良好,方法的检出限为0.2~23.6 ng/L,样品的加标回收率在89.6% ~ 108.4%之间,RSD在1.6% ~3.8%之间.方法能准确测定SCR脱硝尿素中的多个微量元素,可用于SCR脱硝尿素的质量控制和安全评价. 相似文献
863.
根据微生物之间协同关系的微生态理论筛选、组合获得一种由6株功能菌组成的除臭复合菌剂,该复合菌剂对粪便原位除臭效果良好,对综合恶臭的平均去除率为54.97%,最大去除率为72.95%。通过16 S r DNA、18S r DNA和26S r DNA D1/D2区序列同源性分析,菌剂中的6种微生物为罗伦隐球酵母菌(Cryptococcus laurentii)、Bacillus safensis、枯草芽孢杆菌(Bacillus subtilis)、卷枝毛霉(Mucor circinelloides)、发酵乳杆菌(Lactobacillus fermentum)和沼泽红假单胞菌(Rhodopseudomonas palustris),鉴定结果表明,复合菌剂中有酵母菌、芽孢杆菌、霉菌、乳酸菌及光合菌,这些功能菌属于当前生物除臭复合菌剂中的主流菌群。 相似文献
864.
Nutrient and dissolved inorganic carbon are two important factors that influence the development and species composition of submerged macrophyte communities in shallow lake ecosystems. Yet little is known about their potential interactive effects on the submerged macrophytes and competition outcome of macrophyte–phytoplankton. We performed a mesocosm experiment to investigate the growth and photosynthetic performance of three submerged macrophytes in relation to phytoplankton/epiphyton with nutrient and bicarbonate enrichment. During the experimental period (42 d), increase in nutrient loading in water column resulted in a substantial burst of phytoplankton and epiphyton growth and increased light attenuation. When combined with nutrient loading, bicarbonate enrichment also resulted in a heavily phytoplankton- and epiphyton-dominated state, although bicarbonate enrichment per se does not cause the phytoplankton and epiphyton growth. However, increase in nutrient loading in water column had significant negative impact on individual performances (growth and photosynthesis) of the three submerged macrophytes and bicarbonate enrichment increased the effect of eutrophication on two dissected-leaf macrophytes (M. spicatum and E. nuttallii). Furthermore, our results also suggest that species-specific photosynthetic performances occurred when submerged macrophytes in an environment with high abundance of phytoplankton/epiphyton. This study highlighted that increase in nutrient loading and bicarbonate in water column is likely to interactively impact both abiotic and biotic properties of a freshwater ecosystem. The interactions of these two factors could select macrophyte species that are able to resist the shading from phytoplankton/epiphyton, making these species more dominant in natural freshwater ecosystems. 相似文献
865.
An innovative haloacetic acid (HAA) removal process was developed. The process consisted of a zero-valent iron (Fe0) column followed by a biologically active carbon (BAC) column that were efficient in degrading tri- and di-HAAs, and mono- and di-HAAs, respectively. The merit of the process was demonstrated by its performance in removing trichloroacetic acid (TCAA). An empty bed contact time of 10 min achieved nearly complete removal of 1.2 μM TCAA and its subsequent products, dichloroacetic acid (DCAA) and monochloroacetic acid (MCAA). HAA removal was a result of chemical dehalogenation and biodegradation rather than physical adsorption. Preliminary kinetic analyses were conducted and the pseudo-first-order rate constants were estimated at ambient conditions for Fe0 reduction of TCAA and biodegradation of DCAA and MCAA by BAC. This innovative process is highly promising in removing HAAs from drinking water, swimming pool water, and domestic or industrial wastewater. 相似文献
866.
Kai Wang Jin Cai Jia Feng Shulian Xie 《Environmental monitoring and assessment》2014,186(12):8667-8681
Removing phenol from wastewater has become a major challenge of international concern. Phytoremediation is a novel and eco-friendly method and is attracting an increasing amount of attention for treating phenol in wastewater. We studied the ability of Polygonum orientale, which is frequently present around water bodies and in wetlands in China, to phytoremediate phenol. We determined the inhibition concentration for phenol on P. orientale using emergency toxicology experiments and morphological observations. Isothermal and kinetic models were created to assess the adsorption process involved in phenol removal. Comparison tests in sterile conditions demonstrated that metabolic removal was the main way in which the phenol concentrations were decreased, and removal by adsorption played a smaller role. An orthogonal test was performed to determine the optimum conditions under which P. orientale will remove phenol, and these were found to be an initial phenol concentration of 5 mg L?1, 100 % natural light, and a 13-day treatment time. These results provide a theoretical basis for increasing our understanding of the mechanisms involved in the removal of phenol by P. orientale and will help in developing its application in the greening of urban areas to provide both phytoremediation and esthetic landscaping. 相似文献
867.
868.
Xie Z Ebinghaus R Flöser G Caba A Ruck W 《Environmental pollution (Barking, Essex : 1987)》2008,156(3):1190-1195
The potential of triclosan (TCS) acting as an endocrine disruptor has led to growing concern about the presence of TCS in the environment. In this study, seawater samples were collected from the German Bight during sampling campaigns conducted with the German research ships Gauss and Ludwig Prandtl. TCS was determined both in the dissolved phase and in the suspended particulate matters with concentrations ranging 0.8-6870 pg L−1 and <1-95 pg L−1, respectively. High concentrations of TCS were present in the estuaries of the Elbe and the Weser, indicating significant input of TCS by the river discharge. The correlation coefficient (R2) between the dissolved concentration and salinity was 0.79 for the data obtained from the Gauss cruise, showing an obvious declining trend from the coast to the open sea. 相似文献
869.
870.