全文获取类型
收费全文 | 401篇 |
免费 | 3篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 5篇 |
废物处理 | 28篇 |
环保管理 | 31篇 |
综合类 | 37篇 |
基础理论 | 43篇 |
污染及防治 | 165篇 |
评价与监测 | 65篇 |
社会与环境 | 31篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 3篇 |
2022年 | 26篇 |
2021年 | 42篇 |
2020年 | 11篇 |
2019年 | 11篇 |
2018年 | 18篇 |
2017年 | 22篇 |
2016年 | 30篇 |
2015年 | 11篇 |
2014年 | 26篇 |
2013年 | 37篇 |
2012年 | 22篇 |
2011年 | 30篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 14篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 10篇 |
2004年 | 5篇 |
2003年 | 8篇 |
2002年 | 8篇 |
2001年 | 3篇 |
2000年 | 4篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有408条查询结果,搜索用时 15 毫秒
261.
R. R. Miranda A. L. R. Damaso da Silveira I. P. de Jesus S. R. Grötzner C. L. Voigt S. X. Campos J. R. E. Garcia M. A. F. Randi C. A. Oliveira Ribeiro F. Filipak Neto 《Environmental science and pollution research international》2016,23(6):5179-5188
The impact of nanoparticles on fish health is still a matter of debate, since nanotechnology is quite recent. In this study, freshwater benthonic juvenile fish Prochilodus lineatus were exposed through water to three concentrations of TiO2 (0.1, 1, and 10 μg l?1) and ZnO (7, 70, and 700 μg l?1) nanoparticles, as well as to a mixture of both (TiO2 1 μg l?1?+?ZnO 70 μg l?1) for 5 and 30 days. Nanoparticle characterization revealed an increase of aggregate size in the function of concentration, but suspensions were generally stable. Fish mortality was high at subchronic exposure to 70 and 700 μg l?1 of ZnO. Nanoparticle exposure led to decreased acetylcholinesterase activity either in the muscle or in the brain, depending on particle composition (muscle—TiO2 10 μg l?1; brain—ZnO 7 and 700 μg l?1), and protein oxidative damage increased in the brain (ZnO 70 μg l?1) and gills (ZnO 70 μg l?1 and mixture) but not in the liver. Exposed fish had more frequent alterations in the liver (necrosis, vascular congestion, leukocyte infiltration, and basophilic foci) and gills (hyperplasia and epithelial damages, e.g., epithelial disorganization and epithelial loss) than the control fish. Thus, predicted concentrations of TiO2 and ZnO nanoparticles caused detectable effects on P. lineatus that may have important consequences to fish health. But, these effects are much more subtle than those usually reported in the scientific literature for high concentrations or doses of metal nanoparticles. 相似文献
262.
We assessed the effects of anoxia exposure and recovery on glycogen synthesis and mobilization, glucose uptake, and on the enzymes that control carbohydrate metabolism in the hepatopancreas of Chasmagnathus granulata crabs receiving either a carbohydrate-rich (HC) or a high-protein diet (HP). In both dietary groups, anoxia led to a reduction in glucose uptake and in glycogen synthesis, and to an increase in hepatopancreas glycogen mobilization and in hemolymph glucose concentration. During the first 4 h of exposure to anoxia, total glycogen phosphorylase (GPT) and a form activity increased in HP and HC crabs, leading to a decrease in hepatopancreas glycogen concentration. During recovery, HP and HC crabs rapidly restored the hemolymph glucose levels to pre-anoxia concentrations. In HC crabs, incorporation of 14C from glucose into glycogen increased gradually after 12 h in normoxia, leading to restoration of glycogen concentration. Also during recovery, the ratio of glycogen synthase I (GSI) to glycogen phosphorylase a (GPa) increased in the HC group. In turn, recovering HP crabs had two peaks of glycogen synthesis, related with two peaks in the ratio of GSI to GPa. Consequently, no mobilization of 14C-glycogen occurred in recovering HP animals. Anoxia in C. granulata induces a marked decrease in the synthesis of carbohydrate reserves that is accompanied by an increase in glycogen mobilization and in circulating glucose levels. During the recovery period, there is an activation of endergonic processes which cause a decrease in hemolymph glucose levels. In C. granulata, glycogen metabolism seems to be controlled by the ratio of the GSI form to the GPa form. In field conditions, theses changes in the metabolic pattern may result from environmental PO2 availability. In the winter, C. granulata stays in its holes, where environmental PO2 falls to zero. The carbohydrate or protein content of the diets administrated to the crabs seem to induce different metabolic adjustments during anoxia and recovery. 相似文献
263.
Gerold Gerhard Couto Eduardo Guimarães Madari Beata Emoke Jungkunst Hermann F. Amorim Ricardo Silva Santos Hohnwald Stefan Klingler Michael de Almeida Machado Pedro Luiz Oliveira Schönenberg Regine Nendel Claas 《Regional Environmental Change》2018,18(1):1-9
Regional Environmental Change - 相似文献
264.
Gerenutti M Gonçalves MM Rissato SR de Oliveira JM dos Santos Reigota MA Galhiane MS 《Environmental monitoring and assessment》2012,184(7):4425-4433
This work presents a liquid disposal monitoring originated from uranium enrichment process at Aramar Experimental Center from 1990 to 1998. Assessment of uranium, fluorides, ammoniacal nitrogen, chemical oxygen demand, and pH measurements were made in water samples and compared with results achieved in other countries, as North America and India. The liquid disposal evaluation, generated by uranium enrichment process, showed low levels, considering most parameters established by Federal and State Legislation, aiming environmental pollution control. However, uranium levels were above the limits established by Conselho Nacional do Meio Ambiente, Environment Protection Agency and mainly by the World Health Organization. 相似文献
265.
266.
Oliveira Janaína de Moura Madari Beata Emoke Carvalho Márcia Thaís de Melo Assis Paula Camylla Ramos Silveira André Luiz Rodrigues de Leles Lima Mateus Wruck Flávio Jesus Medeiros João Carlos Machado Pedro Luiz Oliveira de Almeida 《Regional Environmental Change》2018,18(1):105-116
Regional Environmental Change - Integrated farming systems (IS) are one of the main strategies of the Brazilian government to reduce or compensate for carbon emissions from agriculture with... 相似文献
267.
da Silva GS Filipak Neto F Silva de Assis HC Bastos WR de Oliveira Ribeiro CA 《Environmental monitoring and assessment》2012,184(8):4815-4827
Mercury (Hg) is a toxic metal that bioaccumulates in aquatic organisms and along food chain. Many studies have reported the problem of mercury exposure in aquatic systems from Amazon basin, but very few have focused on the potential risks to wild fish. The present study reports the bioaccumulation of mercury and alterations in target organs of the predator fish Hoplias malabaricus (traíra) from Samuel reservoir, Amazon basin, Northern Brazil. About 18% of fish had mercury levels in muscle exceeding the safe limit for ingestion through food, established by WHO (0.5 μg Hg g(-1)). Fish were separated in two groups according to mercury bioaccumulation in liver (<0.2 μg Hg g(-1)-group I and >0.2 μg Hg g(-1)-group II) for biomarker comparisons. Catalase activity and number of macrophage centers were statistically higher in group II, confirming the potential of Hg to interfere with redox balance and to recruit defense cells to the liver. Conversely, erythrocyte nuclear alterations were less frequent in group II, indicating a more rigorous selection of erythrocytes or hormesis pattern of response. Glutathione S-transferase activity, lipid peroxidation, and histopathological analyses were not statistically different in the liver and gills of both groups. Comparison of lipid peroxidation levels of these fish with others captured in Southern Brazil during another study and the high incidence of morphological alterations in the liver and gills suggest that the bioaccumulation of mercury during continuous exposure is posing potential risks to the species. 相似文献
268.
Patrícia Trevisan Juliane Nascimento da Silva Alessandra Pawelec da Silva Rafael Fabiano Machado Rosa Giorgio Adriano Paskulin Flávia Valladão Thiesen Ceres Andréia Vieira de Oliveira Paulo Ricardo Gazzola Zen 《Environmental monitoring and assessment》2014,186(4):2195-2204
The search for reliable biomarkers of human exposure to benzene and its derivatives is still subject of research. Many of the proposed biomarkers have limitations ranging from the low sensitivity to the wide variability of results. Thus, the aim of our study was to assess the frequencies of chromosomal abnormalities (CA) and sister chromatid exchanges (SCE) in workers of gas stations, with (cases, n?=?19) and without (local controls, n?=?6) risk of exposure to benzene and its derivatives, comparing them with the results from the general population (external controls, n?=?38). The blood dosages of benzene, toluene, and xylenes were measured in all participants. Blood solvent levels were compared with the findings obtained in cytogenetic evaluation and a research protocol which included data of the workplace, lifestyle, and health of the individuals. We did not detect the presence of benzene and its derivatives and did not find chromosomal damage that may be associated with the gas station activity in cases. Moreover, although we found an association of increased SCE and the working time in the local controls, the values found for SCE are within normal limits. Thus, our evaluation of SCE and CA reflected the levels of benzene and its derivatives observed in the blood. We believe, therefore, that SCE and CA may actually constitute possible tests for the evaluation of these exposures. However, we believe that further studies, including individuals at risk, are important to confirm this assertion. 相似文献
269.
Cláudia B. Lopes Joana R. Oliveira Luciana S. Rocha Daniela S. Tavares Carlos M. Silva Susana P. Silva Niels Hartog Armando C. Duarte E. Pereira 《Environmental science and pollution research international》2014,21(3):2108-2121
The technical feasibility of using stopper-derived cork as an effective biosorbent towards bivalent mercury at environmentally relevant concentrations and conditions was evaluated in this study. Only 25 mg/L of cork powder was able to achieve 94 % of mercury removal for an initial mercury concentration of 500 μg/L. It was found that under the conditions tested, the efficiency of mercury removal expressed as equilibrium removal percentage does not depend on the amount of cork or its particle size, but is very sensitive to initial metal concentration, with higher removal efficiencies at higher initial concentrations. Ion exchange was identified as one of the mechanisms involved in the sorption of Hg onto cork in the absence of ionic competition. Under ionic competition, stopper-derived cork showed to be extremely effective and selective for mercury in binary mixtures, while in complex matrices like seawater, moderate inhibition of the sorption process was observed, attributed to a change in mercury speciation. The loadings achieved are similar to the majority of literature values found for other biosorbents and for other metals, suggesting that cork stoppers can be recycled as an effective biosorbent for water treatment. However, the most interesting result is that equilibrium data show a very rare behaviour, with the isotherm presenting an almost square convex shape to the concentration axis, with an infinite slope for an Hg concentration in solution around 25 μg/L. 相似文献
270.
Pâmela C. Oliveira Elizabete M. Maximiano Poliane A. Oliveira Junior S. Camargo Antonio R. Fiorucci 《Journal of environmental science and health. Part. B》2013,48(12):817-823
AbstractThis paper describes a simple, inexpensive, highly sensitive, selective, and efficient electrochemical method to determine glyphosate (GLY) in samples of milk, orange juice, and agricultural formulation. The oxidation reaction on the electrode surface was electrochemically characterised by cyclic voltammetry (CV) and square wave voltammetry (SWV). The investigation of GLY at carbon paste electrode revealed a non-reversible oxidation peak at +0.95 V versus Ag/AgCl, which was used for electrochemical detection of GLY. The operating parameters (pH, frequency, step potential, and amplitude) were optimised in relation to the peak current intensity, and a calibration curve was set up in a concentration range of 4.40?×?10?8–2.80?×?10?6 mol L?1, with a detection limit of 2?×?10?9 mol L?1. After calibration curve was plotted, the developed procedure was applied to determine GLY in previously contaminated samples: milk and orange juice, and in a commercial formulation, obtaining recovery values between 98.31% and 103.75%. These results show that the proposed method can be used for GLY quantification in different samples with high sensitivity, specificity, stability, and reproducibility. 相似文献