全文获取类型
收费全文 | 362篇 |
免费 | 27篇 |
国内免费 | 237篇 |
专业分类
安全科学 | 6篇 |
废物处理 | 21篇 |
环保管理 | 15篇 |
综合类 | 333篇 |
基础理论 | 113篇 |
污染及防治 | 123篇 |
评价与监测 | 11篇 |
社会与环境 | 4篇 |
出版年
2024年 | 1篇 |
2023年 | 5篇 |
2022年 | 21篇 |
2021年 | 17篇 |
2020年 | 19篇 |
2019年 | 21篇 |
2018年 | 15篇 |
2017年 | 25篇 |
2016年 | 29篇 |
2015年 | 24篇 |
2014年 | 34篇 |
2013年 | 72篇 |
2012年 | 33篇 |
2011年 | 44篇 |
2010年 | 29篇 |
2009年 | 33篇 |
2008年 | 23篇 |
2007年 | 31篇 |
2006年 | 25篇 |
2005年 | 24篇 |
2004年 | 7篇 |
2003年 | 15篇 |
2002年 | 12篇 |
2001年 | 6篇 |
2000年 | 11篇 |
1999年 | 7篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 7篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1987年 | 1篇 |
1986年 | 1篇 |
排序方式: 共有626条查询结果,搜索用时 31 毫秒
31.
Selection of appropriate organic additives for enhancing Zn and Cd phytoextraction by hyperaccumulators 总被引:3,自引:0,他引:3
WU Qi-tang DENG Jin-chuan LONG Xin-xian MOREL Jean-louis SCHWARTZ Christophe 《环境科学学报(英文版)》2006,18(6):1113-1118
Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid (EDTA), citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid (MGWL) from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent (MR) and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration. 相似文献
32.
33.
Ingrid H. Franke-Whittle Andreas Walter Christian Ebner Heribert Insam 《Waste management (New York, N.Y.)》2014,34(11):2080-2089
A study was conducted to determine whether differences in the levels of volatile fatty acids (VFAs) in anaerobic digester plants could result in variations in the indigenous methanogenic communities. Two digesters (one operated under mesophilic conditions, the other under thermophilic conditions) were monitored, and sampled at points where VFA levels were high, as well as when VFA levels were low. Physical and chemical parameters were measured, and the methanogenic diversity was screened using the phylogenetic microarray ANAEROCHIP. In addition, real-time PCR was used to quantify the presence of the different methanogenic genera in the sludge samples. Array results indicated that the archaeal communities in the different reactors were stable, and that changes in the VFA levels of the anaerobic digesters did not greatly alter the dominating methanogenic organisms. In contrast, the two digesters were found to harbour different dominating methanogenic communities, which appeared to remain stable over time. Real-time PCR results were inline with those of microarray analysis indicating only minimal changes in methanogen numbers during periods of high VFAs, however, revealed a greater diversity in methanogens than found with the array. 相似文献
34.
35.
Phospholipid fatty acids (PLFA) have been widely used to characterize environmental microbial communities, generating community profiles that can distinguish phylogenetic or functional groups within the community. The poor specificity of organism groups with fatty acid biomarkers in the classic PLFA-microorganism associations is a confounding factor in many of the statistical classification/clustering approaches traditionally used to interpret PLFA profiles. In this paper we demonstrate that non-linear statistical learning methods, such as a support vector machine (SVM), can more accurately find patterns related to uranyl nitrate exposure in a freshwater periphyton community than linear methods, such as partial least squares discriminant analysis. In addition, probabilistic models of exposure can be derived from the identified lipid biomarkers to demonstrate the potential model-based approach that could be used in remediation. The SVM probability model separates dose groups at accuracies of ∼87.0%, ∼71.4%, ∼87.5%, and 100% for the four groups; Control (non-amended system), low dose (amended at 10 μg U L−1), medium dose (amended at 100 μg U L−1), and high dose (500 μg U L−1). The SVM model achieved an overall cross-validated classification accuracy of ∼87% in contrast to ∼59% for the best linear classifier. 相似文献
36.
37.
By using dialysis equilibrium experiments, the sorption of a branched nonylphenol isomer [4-(1-ethyl-1,3-dimethylpentyl)-phenol] (NP111) on various humic acids (HAs) isolated from river sediments and two reference HAs was studied. The HAs were characterized by solid-state 13C direct polarization/magic angle spinning nuclear magnetic resonance (13C DP/MAS NMR) spectroscopy. Sorption isotherms of NP111 on HAs were described by a linear model. The organic carbon-normalized sorption coefficient (KOC) ranged from 2.3 × 103 to 1.5 × 104 L kg−1. Interestingly, a clear correlation between KOC value and alkyl C content was observed, indicating that the aliphaticity of HAs markedly dominates the sorption of NP111. These new mechanistic insights about the NP111 sorption indicate that the fate of nonylphenols in soil or sediment depends not only on the content of HA, but also on its structural composition. 相似文献
38.
Mobility of Cd and Cu in formulated sediments coated with iron hydroxides and/or humic acids: a DGT and DGT-PROFS modeling approach 总被引:1,自引:0,他引:1
The diffusive gradients technique in thin films (DGT) was used to investigate the kinetic resupply of Cd and Cu to pore water from the solid phase. For the sake of simplification, experiments were performed using formulated sediments that differed in the presence or absence of humic acids (HA) and/or of iron hydroxides (i.e., goethite and ferrihydrite). The effects of the time after the contamination of the solid phase (aging effect) on formulated sediments that were coated with goethite and HA and spiked with Cd were also evaluated. Kinetic DGT results were interpreted using the newly developed, multi-compartmental model DGT-PROFS.Due to Cu humate formation, the addition of HA slightly increased the Cu concentration in the pore water independent of the effect of the iron hydroxide coating on the formulated sediments and slightly decreased that of Cd. The impact of 8-190 d of aging resulted in a significant decrease in the Cd concentration of the pore water over an increasing incubation time.Modeling our results with DGT-PROFS led to the following conclusions concerning the impact of HA and iron hydroxides on Cd and Cu availability. First, in the presence of HA and absence of iron hydroxides, Cd is associated mainly with weak sites, while Cu is bound to strong sites. Similarly, in the presence of both iron hydroxides and HA, Cu appeared to be more heavily associated with the strong sites than did Cd. When the incubation time increased from 8 to 190 d, a proportion of Cd initially adsorbed onto weak sites transferred to the strong sites, suggesting that the adsorption of Cd on sediments is controlled partially by slow kinetic processes. 相似文献
39.
Szlinder-Richert J Usydus Z Malesa-Ciećwierz M Polak-Juszczak L Ruczyńska W 《Chemosphere》2011,85(11):1725-1733
Chemical analyses were performed in nine fish species that are popular on the Polish market. These included Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), marine fish imported from China (Alaska pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The nutritional composition (amino acid, micro- and macronutrients, fat-soluble vitamins - A1, D3, E) and certain contaminants (organochlorine pesticides, OCPs; indicator polychlorinated biphenyl, PCB6; polychlorinated dibenzo-paradioxins and polychlorinated dibenzofurans, PCDD/Fs; dioxin-like polychlorinated biphenyls, dl-PCBs; organotin compounds, OCTs; dyes, malachite green and crystal violet; veterinary drug residues, nitrofurans and chloramphenicol; toxic metals, Cd, Pb, Hg) in the muscle tissues of fish were determined. It was confirmed that the fish species analyzed were excellent sources of amino acids, and were rich in phosphorous and selenium. Baltic Sea fish (salmon, herring), fish farmed in Poland (carp and trout), and tilapia were also rich in vitamin D3.Traces of OCP, PCB6, OCT, dyes, veterinary drug residues, and heavy metals were detected in concentrations which do not pose a threat to consumers at the current rate of fish consumption in Poland. However, the problem might arise from the content of PCDD/Fs and dl-PCBs in fatty Baltic fish. The fish species analyzed, differed in their nutritional values and degrees of contamination. We suggest that for optimum health and safety, it is advisable that consumers include a variety of different fish species in their diets. 相似文献
40.
合成了H3PMo12O40、H4SiW12O40、H3PW12O40、H4PMo11VO40、H5PMo10V2O40和H6PMo9V3O406种杂多酸,分别采用红外光谱(FT-IR)和X射线衍射(XRD)表征杂多酸的结构,并采用气相色谱仪对6种杂多酸水溶液进行脱硫实验测试。实验结果表明:制备的6种杂多酸具有良好的Keggin型结构;H3PMo12O40、H3PW12O40和H4SiW12O40的3种水溶液中,磷钼杂多酸的脱硫性能最好,脱硫率在120 min时可达到16.38%;不同比例的多原子也会使杂多酸有不同的脱硫性能,脱硫性能顺序为:H6PMo9V3O40〉H5PMo10V2O40〉H4PMo11VO40;且6种杂多酸的脱硫稳定性的顺序为:H4PMo11VO40〉H6PMo9V3O40〉H3PMo12O40〉H5PMo10V2O40〉H4SiW12O40≈H3PW12O40。 相似文献