全文获取类型
收费全文 | 269篇 |
免费 | 1篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 8篇 |
废物处理 | 22篇 |
环保管理 | 10篇 |
综合类 | 23篇 |
基础理论 | 52篇 |
污染及防治 | 104篇 |
评价与监测 | 34篇 |
社会与环境 | 16篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 6篇 |
2022年 | 22篇 |
2021年 | 19篇 |
2020年 | 12篇 |
2019年 | 11篇 |
2018年 | 18篇 |
2017年 | 23篇 |
2016年 | 21篇 |
2015年 | 9篇 |
2014年 | 27篇 |
2013年 | 30篇 |
2012年 | 10篇 |
2011年 | 13篇 |
2010年 | 7篇 |
2009年 | 9篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1994年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有272条查询结果,搜索用时 15 毫秒
151.
A study on the incorporation of coal bottom ash from thermoelectric power stations as a substitute material for natural sand in the production of concrete is here presented. The normally coarse, fused, glassy texture of bottom ash makes it an ideal substitute for natural aggregates. The use of bottom ash in concrete presents several technical challenges: the physical and mineralogical characteristics of the bottom ash; the effect on water demand and the participation on cements hydratation. In the production of the concrete, substitutions in volume were used. Two different ways to employ bottom ash were used to make up the mix proportions: one considering the natural humidity present in the porous particles and the other not considering it, seeking to maintain the same strength. These considerations are fundamental given that the process of bottom ash extraction is carried out through moisture. Mechanical tests by compressive strength were performed and the elastic modulus was determined. An analysis of the influence of bottom ash in the formation of pores was carried out through tests for the water loss by air drying and water uptake by capillary absorption. The results show that the higher the bottom ash contents in the concrete, the worse the performance regarding moisture transport. However, for one bottom ash concrete type, the mechanical properties were maintained. 相似文献
152.
Peixoto NC Rocha LC Moraes DP Bebianno MJ Dressler VL Flores EM Pereira ME 《Chemosphere》2008,72(9):1327-1332
The effect of mercury and its interaction with zinc on the content of essential metals in tissues from neonate rats was investigated. Three-day-old Wistar rats were treated with saline or 27 mg kg(-1)d(-1) ZnCl2 (s.c.) for five consecutive days. From the 8th to the 12th day of life, the rats received one daily dose of saline or 5.0 mg kg(-1) HgCl2 (s.c). Twenty-four hours after the last injection liver, kidneys and blood were collected for metal quantification. The HgCl(2) exposure induced alterations on metal levels, such as increase of Fe, Hg and Zn in liver, decrease of Fe and Mg and increase of Cu and Hg contents in kidneys. The Hg exposure also increased Hg levels in the blood. The treatment with ZnCl2, administered previously to HgCl2, partially prevented the increase of Fe in the liver, and not only prevented the decrease of renal Mg but also increased it to levels higher than those found in control group. The Zn-Hg rats also presented higher renal Cu levels, and showed partially lower blood and hepatic Hg levels and higher renal Hg levels. The pre-administration of Zn caused no severe alterations in levels of essential metals (Cu, Fe, Mg and Mn). In short, Zn appears to be an alternative treatment of Hg poisoning in young animals in comparison to chelating drugs since these have low metal selectivity. 相似文献
153.
154.
Grassi Patrícia Drumm Fernanda Caroline Georgin Jordana Franco Dison Stracke Pfingsten Dotto Guilherme Luiz Foletto Edson Luiz Jahn Sérgio Luiz 《Environmental science and pollution research international》2021,28(6):6771-6783
Environmental Science and Pollution Research - In this work, for the first time, Cordia trichotoma sawdust, a residue derived from noble wood processing, was applied as an alternative biosorbent... 相似文献
155.
156.
Juliana Ferreira Floriano Natan Roberto de Barros José Luiz Ferreira Cinman Rosangela Gonçalves da Silva Augusto Villela Loffredo Felipe Azevedo Borges Ana Maria Queiros Norberto Ana Laura Destro Chagas Bruna Cambraia Garms Carlos Frederico de Oliveira Graeff Rondinelli Donizetti Herculano 《Journal of Polymers and the Environment》2018,26(6):2281-2289
Ketoprofen is an analgesic with potent anti-inflammatory activity against acute inflammation, subacute inflammation, for the acute and long-term treatment of various inflammatory pathologies, as rheumatoid arthritis and colonic adenocarcinoma. In order to minimize the incidence of systemic events related to ketoprofen, the transdermal drug delivery system development has been most important. The advantages of using natural rubber latex membranes include not only the reduction of adverse systemic events, but also the suitability of the low cost of the material together with its physicochemical properties such as flexibility, mechanical stability, surface porosity and water vapor permeability, and besides being a biocompatible material also presents biological activity to stimulate the angiogenesis, being able to be used in tissue repair. This study demonstrated that ketoprofen was successfully incorporated into natural latex membranes for drug delivery. FTIR indicated that the drug did not interact chemically with the membrane. Moreover, the natural latex membranes released 60% of the ketoprofen incorporated in 50 h. SEM images indicated that a portion of the drug was present on the membrane surface, being this portion responsible for the burst release. The tensile tests showed that the addition of the drug into the natural latex membrane did not influence on the polymer mechanical behavior. In addition, drug-natural latex membranes presented no red blood cell damaging effects. Our data shows that the ketoprofen loaded natural latex membranes is a promising system for sustained drug delivery which can be used to minimize the adverse side effects of high dose systemic drug delivery. 相似文献
157.
158.
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
159.
David W. Watkins Jr. Márcia M. G. Alcoforado de Moraes Heidi Asbjornsen Alex S. Mayer Julian Licata Jose Gutierrez Lopez Thomas G. Pypker Vivianna Gamez Molina Guilherme Fernandes Marques Ana Cristina Guimaraes Carneiro Hector M. Nuñez Hayri Önal Bruna da Nobrega Germano 《Environmental management》2015,56(6):1295-1314
160.
Sanchez Rodriguez Mdel R Lugo Vazquez A Oliva Martinez MG Verver y Vargas JG Rodriguez Rocha A Peralta Soriano L 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(4):497-503
Taxonomical composition and abundance of the planktonic ciliate assemblage in a Lake Tezozomoc, a hypertrophic pond located into an urban park in Mexico City, was investigated along the rainy season (May to October). The aims of the study were to know the main trophic roles and ecological significance of ciliates in a highly productive environment. A low number of taxa (27) and a wide abundance fluctuation (104-387 cil ml(-1)) were found. The most abundant species (up to 162 cil ml(-1)) was Halteria grandinella, an oligotrich ciliate that graze on bacteria and picoplankton, but also several big body sized species that feed on pico and nanoplankton were abundant. Sudden temporal changes in species dominance occurred. Ciliate biomass was very high and fluctuated widely (1.6-88 10(6) microm(3) ml(-1)) being dominated by the >50 microm size fraction that mainly included the pico and nanoplankton feeders. Ciliates are a very important component in the plankton of hypertrophic lakes and their main control factor seems to be the grazing by big-body size Daphnia species. 相似文献