全文获取类型
收费全文 | 11333篇 |
免费 | 79篇 |
国内免费 | 84篇 |
专业分类
安全科学 | 283篇 |
废物处理 | 504篇 |
环保管理 | 1431篇 |
综合类 | 2460篇 |
基础理论 | 2556篇 |
环境理论 | 5篇 |
污染及防治 | 2956篇 |
评价与监测 | 684篇 |
社会与环境 | 562篇 |
灾害及防治 | 55篇 |
出版年
2022年 | 91篇 |
2021年 | 96篇 |
2019年 | 69篇 |
2018年 | 149篇 |
2017年 | 131篇 |
2016年 | 222篇 |
2015年 | 172篇 |
2014年 | 243篇 |
2013年 | 821篇 |
2012年 | 304篇 |
2011年 | 427篇 |
2010年 | 337篇 |
2009年 | 397篇 |
2008年 | 428篇 |
2007年 | 492篇 |
2006年 | 432篇 |
2005年 | 353篇 |
2004年 | 369篇 |
2003年 | 373篇 |
2002年 | 332篇 |
2001年 | 428篇 |
2000年 | 312篇 |
1999年 | 205篇 |
1998年 | 115篇 |
1997年 | 123篇 |
1996年 | 108篇 |
1995年 | 154篇 |
1994年 | 148篇 |
1993年 | 123篇 |
1992年 | 130篇 |
1991年 | 149篇 |
1990年 | 119篇 |
1989年 | 127篇 |
1988年 | 132篇 |
1987年 | 114篇 |
1986年 | 83篇 |
1985年 | 99篇 |
1984年 | 124篇 |
1983年 | 125篇 |
1982年 | 123篇 |
1981年 | 97篇 |
1980年 | 93篇 |
1979年 | 106篇 |
1978年 | 89篇 |
1977年 | 84篇 |
1976年 | 78篇 |
1975年 | 90篇 |
1974年 | 101篇 |
1972年 | 69篇 |
1965年 | 74篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
882.
Liesbeth Weijs Sara Losada Krishna Das Laurence Roosens Peter J.H. Reijnders Javier F. Santos Hugo Neels Ronny Blust Adrian Covaci 《Environment international》2009,35(6):893-899
Harbour seals and harbour porpoises are top predator species from the North Sea, have long life spans and hence, are known to accumulate high levels of anthropogenic contaminants. To gain knowledge about the behaviour of naturally-produced compounds in these marine mammals, the biomagnification of naturally-produced methoxylated polybrominated diphenyl ethers (MeO-PBDEs) was assessed. The biomagnification of MeO-PBDEs (2′-MeO-BDE 68 and 6-MeO-BDE 47) was lower in harbour seals (all biomagnification factors (BMFs) < 1) compared to the same age–gender groups of the harbour porpoises (all BMFs > 1). This may indicate a better metabolic breakdown of MeO-PBDEs in harbour seals, as was previously suggested for polybrominated diphenyl ethers (PBDEs). In both predators, 6-MeO-BDE 47 had the highest concentrations (range: 45–483 ng/g lw and 2–38 ng/g lw for harbour porpoises and seals, respectively) compared to 2′-MeO-BDE 68 (range: 2–28 ng/g lw and 1–6 ng/g lw for harbour porpoises and seals, respectively). In general, the highest concentrations were found in juveniles, suggesting an increased biotransformation capacity with age or the influence of dilution by growth for both species. Here we show that naturally-produced brominated organic compounds can biomagnify and accumulate in North Sea top predators, although to a lesser extent than anthropogenic lipophilic contaminants, such as polychlorinated biphenyls (PCBs) or PBDEs. 相似文献
883.
Kenneth F. Hedden Lee A. Mulkey William A. Tucker 《Environmental monitoring and assessment》1982,2(1-2):57-69
A potentially important exposure route for humans is the ingestion of chemicals via drinking water. If comprehensive exposure assessments are to be completed for either existing or proposed new chemicals and cost effective control strategies developed, then a quantitative understanding of multimedia transport and fate of specific chemical pollutants must be achieved. Mathematical models provide a powerful framework into which quantitative relationships may be placed to provide guidance in reaching water quality goals. Existing, state-of-the-art media-specific toxic organic transport and fate models for atmospheric (DiDOT), land surface (NPS) and surface water processes (EXAMS) and potable water treatment (WTP) have been linked to demonstrate the technical feasibility of such an approach. Limited application and sensitivity testing of this linked modeling system has shown that the impact of various source loadings and control strategies on drinking water quality can be estimated. 相似文献
884.
Transport of simazine in unsaturated sandy soil and predictions of its leaching under hypothetical field conditions 总被引:2,自引:0,他引:2
Suárez F Bachmann J Muñoz JF Ortiz C Tyler SW Alister C Kogan M 《Journal of contaminant hydrology》2007,94(3-4):166-177
The potential contamination of groundwater by herbicides is often controlled by processes in the vadose zone, through which herbicides travel before entering groundwater. In the vadose zone, both physical and chemical processes affect the fate and transport of herbicides, therefore it is important to represent these processes by mathematical models to predict contaminant movement. To simulate the movement of simazine, a herbicide commonly used in Chilean vineyards, batch and miscible displacement column experiments were performed on a disturbed sandy soil to quantify the primary parameters and processes of simazine transport. Chloride (Cl(-)) was used as a non-reactive tracer, and simazine as the reactive tracer. The Hydrus-1D model was used to estimate the parameters by inversion from the breakthrough curves of the columns and to evaluate the potential groundwater contamination in a sandy soil from the Casablanca Valley, Chile. The two-site, chemical non-equilibrium model was observed to best represent the experimental results of the miscible displacement experiments in laboratory soil columns. Predictions of transport under hypothetical field conditions using the same soil from the column experiments were made for 40 years by applying herbicide during the first 20 years, and then halting the application and considering different rates of groundwater recharge. For recharge rates smaller than 84 mm year(-1), the predicted concentration of simazine at a depth of 1 m is below the U.S. EPA's maximum contaminant levels (4 microg L(-1)). After eight years of application at a groundwater recharge rate of 180 mm year(-1) (approximately 50% of the annual rainfall), simazine was found to reach the groundwater (located at 1 m depth) at a higher concentration (more than 40 microg L(-1)) than the existing guidelines in the USA and Europe. 相似文献
885.
886.
F. Owen Hoffman B. Gordon Blaylock Marilyn L. Frank Kathleen M. Thiessen 《Environmental monitoring and assessment》1993,28(3):221-237
Contamination at Superfund sites can involve mixtures of chemicals and radionuclides in a variety of environmental media. Determining priorities for evaluation and remediation of various contaminants is an important part of the initial phases of any site investigation. An effective screening analysis at the beginning of the project can help by identifying both those situations in need of immediate remedial attention and those which require further sampling and evaluation. The screening approach discussed here is made up of two sets of calculations designed to provide upper- and lower-bound estimates of health risk to individuals likely to receive the highest exposures. This approach allows rapid identification of contaminants which pose a negligible risk and can be assigned a low priority for remedial attention or which pose a substantial risk and should be given the highest priority for appropriate remediation efforts. Contaminants designated as neither high- nor low-priority should be investigated in more detail prior to making decisions regarding the need for or method of remediation. The utility of this approach has already been demonstrated in the evaluation of contamination in the Clinch and Tennessee River systems originating from historical operations of atomic weapons and energy research facilities near Oak Ridge, Tennessee. 相似文献
887.
Environmental audits: Proposed terminology 总被引:1,自引:0,他引:1
This paper presents a review of the fast developing subject of environmental auditing with the authors proposing a series of definitions. Of particular concern is a move towards the development of an accepted vocabulary for environmental impact assessment, even though the international dimension of the subject makes this a difficult task. Use of the word audit has become an accepted part of EIA vocabulary, however there are several types of audits being undertaken today. Presently, there are no commonly accepted definitions, consequently this paper will attempts to address this issue. Definitions for seven types of environmental audits are suggested, derived from the experience of the authors and from a review of the current literature. It is hoped that by the presentation of these definitions that such terms will be advocated for future EIA work, and thereby reducing confusion that otherwise may occur. The paper concludes with a brief review of the status of auditing. 相似文献
888.
Larissa Stieven Montagna Thaís Larissa do Amaral Montanheiro Fábio Roberto Passador Ana Paula Lemes Mirabel Cerqueira Rezende 《Journal of Polymers and the Environment》2018,26(4):1511-1519
The potential use of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/graphite nanosheets (GNS) as a biodegradable nanocomposite has been explored. PHBV/GNS nanocomposites films were prepared by solution casting at various concentrations of GNS—0.25, 0.50 and 1.00 wt% GNS. The films were exposed to artificial ultraviolet radiation (UV) during 52 h. The effect of GNS on PHBV photodegradation was investigated and compared to neat PHBV film. The artificial photodegradation induced changes in physical (weight loss), chemical carbonyl index by Fourier transform infrared spectroscopy, thermal degree of crystallinity and melting temperature by differential scanning calorimetry and morphological scanning electron microscopy characteristics. Based on the results obtained from aforementioned analyzes it was verified that GNS inhibits the oxidative degradation of PHBV matrix. 相似文献
889.
Chemical, biological, and ecotoxicological assessment of pesticides and persistent organic pollutants in the Bahlui River, Romania 总被引:1,自引:0,他引:1
Mariana Neamtu Ioan M. Ciumasu Naela Costica Mihai Costica Magda Bobu Mircea N. Nicoara Cezar Catrinescu Kristin Becker van Slooten Luiz F. De Alencastro 《Environmental science and pollution research international》2009,16(Z1):76-85
Background, aim, and scope
Current knowledge on environmental impacts of industrial activities in Romania, particularly persistent organic pollutants (POPs), indicates that environmental standards of the European Union are not systematically met. In our study area, additional sources of POPs are agriculture and domestic wastes. Very scarce information is available upon environmental contaminations and effects. In the present study, we investigated the chemical pollution and their eventual impact on the ecosystem by measuring POPs and by using biological indicators of pollution. 相似文献890.
Patchy distributions: Optimising sample size 总被引:1,自引:0,他引:1
J. E. Hewitt G. B. Mcbride R. D. Pridmore S. F. Thrush 《Environmental monitoring and assessment》1993,27(2):95-105
A method for estimating sample size which does not require an a priori definition of desired precision, or the assumption that the population is normally distributed with constant variance, has recently been proposed. This paper discusses this method and presents five modifications which make the method easier to use and reduce the probability of estimating a larger sample size than is actually required. The method is extended and used to estimate the mean abundance of patchily distributed benthic organisms. The technique can be used to guide the design of any environmental sampling programme, be it physical, chemical or biological, where comparisons between times and/or locations are required. Trade-offs between numbers of replicates and numbers of levels/sites are discussed. 相似文献