全文获取类型
收费全文 | 1922篇 |
免费 | 29篇 |
国内免费 | 19篇 |
专业分类
安全科学 | 55篇 |
废物处理 | 69篇 |
环保管理 | 315篇 |
综合类 | 310篇 |
基础理论 | 455篇 |
环境理论 | 4篇 |
污染及防治 | 515篇 |
评价与监测 | 146篇 |
社会与环境 | 93篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 20篇 |
2022年 | 22篇 |
2021年 | 28篇 |
2020年 | 27篇 |
2019年 | 25篇 |
2018年 | 40篇 |
2017年 | 48篇 |
2016年 | 47篇 |
2015年 | 51篇 |
2014年 | 54篇 |
2013年 | 137篇 |
2012年 | 80篇 |
2011年 | 121篇 |
2010年 | 81篇 |
2009年 | 95篇 |
2008年 | 105篇 |
2007年 | 126篇 |
2006年 | 88篇 |
2005年 | 82篇 |
2004年 | 77篇 |
2003年 | 71篇 |
2002年 | 83篇 |
2001年 | 35篇 |
2000年 | 26篇 |
1999年 | 19篇 |
1998年 | 20篇 |
1997年 | 23篇 |
1996年 | 18篇 |
1995年 | 23篇 |
1994年 | 26篇 |
1993年 | 14篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 12篇 |
1989年 | 12篇 |
1988年 | 17篇 |
1987年 | 12篇 |
1986年 | 16篇 |
1984年 | 8篇 |
1983年 | 10篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 8篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1974年 | 6篇 |
1955年 | 5篇 |
1954年 | 8篇 |
排序方式: 共有1970条查询结果,搜索用时 953 毫秒
631.
Baldrian P Merhautová V Cajthaml T Nerud F Stopka P Gorbacheva O Hrubý M Benes MJ 《Chemosphere》2008,72(11):1721-1726
Chelating sorbents with diethylenetriaminepenta(methylene-phosphonic acid) (DTPMPA) and ethylenediaminetetraacetic acid ligands immobilized on zirconia matrix were prepared and subsequently saturated with Cu(II). All the Cu chelates catalyzed decomposition of H(2)O(2) yielding highly reactive hydroxyl radicals. All of them were also able to catalyze degradation of polycyclic aromatic hydrocarbons (anthracene, benzo[a]pyrene and benzo[b]fluoranthene). The most effective DTPMPA-based catalysts G-32 and G-35 (10 mg ml(-1) with 100 mmol H(2)O(2)) caused almost complete decomposition of 15 ppm anthracene and benzo[a]pyrene during a five day catalytic cycle at 30 degrees C. Anthracene-1,4-dione was the main product of anthracene oxidation by all catalysts. The catalysts were active in several cycles without regeneration. 相似文献
632.
Schmitt C Oetken M Dittberner O Wagner M Oehlmann J 《Environmental pollution (Barking, Essex : 1987)》2008,152(2):322-329
The two UV screens 3-benzylidene-camphor (3-BC) and 3-(4'-methylbenzylidene)-camphor (4-MBC) were tested regarding their toxicity and estrogenic activity. The Yeast Estrogen Screen (YES) and two sediment assays with the freshwater invertebrates Lumbriculus variegatus and Potamopyrgus antipodarum were performed. In the YES, both substances activated the human estrogen receptor alpha with EC50 values of 44.2 microM for 3-BC and 44.3 microM for 4-MBC, whereby 4-MBC attained only 8% of the maximal response of 17beta-estradiol. For P. antipodarum embryo production increased after exposure to both substances (EC50 of 4.60 microM 4-MBC=1.17 mg kg(-1)dw) while mortality increased at high concentrations. The reproduction of L. variegatus was decreased by 3-BC with an EC50 of 5.95 microM (=1.43 mg kg(-1)dw) and also by 4-MBC, where no EC50 could be calculated. While reproduction decreased, the worms' weight increased after exposure to 3-BC with an EC50 of 26.9 microM (=6.46 mg kg(-1) dw), hence the total biomass remained unaffected. 相似文献
633.
Moreau X Saez G Thiéry A Clot-Faybesse O Guiraudie-Capraz G Bienboire-Frosini C Martin C De Jong L 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):574-581
A new simple and sensitive method to distinguish chemically polluted from unpolluted situations in freshwater ecosystems is reported. For this purpose, Chironomus gr thumni larvae were collected from a polluted urban river downstream a sewage treatment plant. For the first time, ELISA assay was used to semi-quantify the multixenobiotic resistance transporters (MXR) in these small pertinent bioindicators. The use of samples immediately fixed in the field gives a delay to isolate larvae and allows multi-sampling along a longitudinal transect in a river at a given time. Results exhibit an induction of MXR proteins in larvae from the polluted river and a deinduction in larvae maintained 11days in unpolluted water. They show new evidences to use midge larvae in biomonitoring environmental programs. They answer to first biomarker calibration steps for the ongoing development of MXR transporters as a detection tool of xenobiotic impacts on bioindicator invertebrates in their freshwater habitats. 相似文献
634.
We investigated seasonal variability of essential fatty acids (EFA) and methyl mercury (MeHg) concentrations in four size categories of planktonic organisms in two coastal lakes. MeHg concentrations increased significantly with increasing plankton size and were independent of plankton taxonomy. However, total EFA increased from seston to mesozooplankton, but decreased in the cladoceran-dominated macrozooplankton size-class. Analysis of EFA patterns revealed that linoleic, alpha-linolenic, arachidonic, and eicosapentaenoic acids increased with increasing zooplankton size, but docosahexaenoic acid (DHA) in the cladoceran-dominated macrozooplankton was generally lower than in seston. This consistent pattern demonstrates that cladocerans, although bioaccumulating MeHg, convey less DHA than similar-sized copepods to their consumers. It is thus evident that fish consuming cladocerans have restricted access to DHA, yet unrestricted dietary access to MeHg. Thus, the structure of planktonic food webs clearly affects the composition of EFA and regulates dietary supply of these essential nutrients, while MeHg bioaccumulates with increasing zooplankton size. 相似文献
635.
Shanley JB Alisa Mast M Campbell DH Aiken GR Krabbenhoft DP Hunt RJ Walker JF Schuster PF Chalmers A Aulenbach BT Peters NE Marvin-DiPasquale M Clow DW Shafer MM 《Environmental pollution (Barking, Essex : 1987)》2008,154(1):143-154
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1ng L(-1) and MeHg was less than 0.2ng L(-1). THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56)ng L(-1) at Sleepers River, Vermont; 112 (0.75)ng L(-1) at Rio Icacos, Puerto Rico; and 55 (0.80)ng L(-1) at Panola Mt., Georgia. Filtered (<0.7microm) THg increased more modestly with flow in association with the hydrophobic acid fraction (HPOA) of DOC, with maximum filtered THg concentrations near 5ng L(-1) at both Sleepers and Icacos. At Andrews Creek, Colorado, THg export was also episodic but was dominated by filtered THg, as POC concentrations were low. MeHg typically tracked THg so that each site had a fairly constant MeHg/THg ratio, which ranged from near zero at Andrews to 15% at the low-relief, groundwater-dominated Allequash Creek, Wisconsin. Allequash was the only site with filtered MeHg consistently above detection, and the filtered fraction dominated both THg and MeHg. Relative to inputs in wet deposition, watershed retention of THg (minus any subsequent volatilization) was 96.6% at Allequash, 60% at Sleepers, and 83% at Andrews. Icacos had a net export of THg, possibly due to historic gold mining or frequent disturbance from landslides. Quantification and interpretation of Hg dynamics was facilitated by the small watershed approach with emphasis on event sampling. 相似文献
636.
Patterson PH Adrizal A Hulet RM Bates RM Myers CA Martin GP Shockey RL van der Grinten M 《Journal of environmental science and health. Part. B》2008,43(2):199-204
This study sought to evaluate the potential of trees planted around commercial poultry farms to trap ammonia (NH(3)), the gas of greatest environmental concern to the poultry industry. Four plant species (Norway spruce, Spike hybrid poplar, Streamco willow, and hybrid willow) were planted on eight commercial farms from 2003 to 2004. Because temperature (T) can be a stressor for trees, T was monitored in 2005 with data loggers among the trees in front of the exhaust fans (11.4 to 17.7 m) and at a control distance away from the fans (48 m) during all four seasons in Pennsylvania. Norway spruce (Picea abies) foliage samples were taken in August 2005 from one turkey and two layer farms for dry matter (DM) and nitrogen (N) analysis. The two layer farms had both Norway spruce and Spike hybrid poplar (Populus deltoides x Populus nigra) plantings sampled as well allowing comparisons of species and the effect of plant location near the fans versus a control distance away. Proximity to the fans had a clear effect on spruce foliar N with greater concentrations downwind of the fans than at control distances (3.03 vs. 1.88%; P < or = 0.0005). Plant location was again a significant factor for foliar N of both poplar and spruce on the two farms with both species showing greater N adjacent to the fans compared to the controls (3.75 vs. 2.32%; P < or = 0.0001). Pooled foliar DM of both plants was also greater among those near the fans (56.17, fan vs. 44.67%, control; P < or = 0.005). Species differences were also significant showing the potential of poplar to retain greater foliar N than spruce (3.52 vs. 2.55%; P < or = 0.001) with less DM (46.00 vs. 54.83%; P < or = 0.05) in a vegetative buffer setting. The results indicated plants were not stressed by the T near exhaust fans with mean seasonal T (13.04 vs. 13.03 degrees C, respectively) not significantly different from controls. This suggested poultry house exhaust air among the trees near the fans would not result in dormancy stressors on the plants compared to controls away from the fans. 相似文献
637.
Barcelo-Quintal MH Cebada-Ricalde MC Trejo-Irigoyen AR Rendon-Osorio RB Manzanilla-Cano JA 《Journal of environmental science and health. Part. B》2008,43(2):120-126
Kinetic studies of endosulfan photochemical degradation in controlled aqueous systems were carried out by ultraviolet light irradiation at lambda = 254 nm. The photolysis of (alpha + beta: 2 + 1) endosulfan, alpha-endosulfan and beta-endosulfan were first-order kinetics. The observed rate constants obtained from linear least-squares analysis of the data were 1 x 10(-4) s(-1); 1 x 10(-4) s(-1); and 2 x 10(-5) s(-1), respectively, and the calculated quantum yields (phi) were 1, 1 and 1.6, respectively. Preliminary differential pulse polarographic (DPP) analysis allowed to observe the possible endosulfan photochemical degradation pathway. This degradation route involves the formation of the endosulfan diol, its transformation to endosulfan ether and finally the ether's complete degradation by observing the potential shifts. 相似文献
638.
Wölz J Engwall M Maletz S Olsman Takner H van Bavel B Kammann U Klempt M Weber R Braunbeck T Hollert H 《Environmental science and pollution research international》2008,15(7):536-553
Background, aim, and scope
As a consequence of flood events, runoff and remobilized sediments may cause an increase of ecotoxicologically relevant effects from contaminant reservoirs. Aquatic and terrestrial organisms as well as cattle and areas of settlement are exposed to dislocated contaminants during and after flood events. In this study, the impacts of two flood events triggered by intense rain at the rivers Neckar and Rhine (Southern Germany) were studied. Effects in correlation to flood flow were assessed at the river Neckar using samples collected at frequent intervals. River Rhine suspended particulate matter (SPM) was sampled over a longer period at normal flow and during a flood event. Three cell lines (H4L1.1c4, GPC.2D.Luc, RTL-W1) were used to compare Ah receptor agonist activity in different biotest systems. Multilayer fractionation was performed to identify causative compounds, focusing on persistent organic contaminants. 相似文献639.
Vojtch Ettler Tom Navrtil Martin Mihaljevi
Jan Rohovec Milan Zuna Ondej ebek Ladislav Strnad Maria Hojdov 《Atmospheric environment (Oxford, England : 1994)》2008,42(24):5968-5977
Mercury (Hg) concentration profiles and historical accumulation rates were determined in three 210Pb-dated cores from a peat deposit in the vicinity of a lead (Pb) smelter at Příbram, Czech Republic. The Hg concentrations in peat samples ranged from 66 to 701 μg kg−1. Cumulative Hg inventories from each core (for the past 150 yr) varied by a factor of 1.4 (13.6–18.5 mg Hg m−2), indicating variations of net Hg accumulation rate within the peat deposit. Historical changes in vegetation cover (leading to variable interception by trees) are probably responsible for this variation in space and time. The uncorrected Hg accumulation rates peaked between the 1960s and 1980s (up to 226 μg m−2 yr−1). Recent findings show that Hg records from peat tend to overestimate historical levels of Hg deposition. Therefore we used the mass loss compensation factor (MLCF) to normalize Hg accumulation rates. These corrected Hg accumulation rates were significantly lower (maximum 129 μg m−2 yr−1) and better corresponded to changes in historical smelter emissions, which were highest in the 1960s. The agreement between the corrected Hg accumulation rates in the uppermost peat sections (2–38 μg m−2 yr−1) and biomonitoring of atmospheric deposition by mosses in several recent years (4.7–34.4 μg m−2 yr−1) shows the usefulness of MLCF application on Hg accumulation in peat archives. However, the MLCF correction was unsuitable for Pb. The recent Pb deposition rates obtained by an independent biomonitoring study using mosses (0.5–127 mg m−2 yr−1) were better correlated with net Pb accumulation rates recorded in peat (7–145 mg m−2 yr−1) than with corrected rates obtained by the MLCF approach (1–28 mg m−2 yr−1). 相似文献
640.