全文获取类型
收费全文 | 449篇 |
免费 | 9篇 |
专业分类
安全科学 | 26篇 |
废物处理 | 20篇 |
环保管理 | 67篇 |
综合类 | 69篇 |
基础理论 | 95篇 |
环境理论 | 1篇 |
污染及防治 | 108篇 |
评价与监测 | 41篇 |
社会与环境 | 28篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 5篇 |
2022年 | 15篇 |
2021年 | 15篇 |
2020年 | 8篇 |
2019年 | 6篇 |
2018年 | 16篇 |
2017年 | 19篇 |
2016年 | 25篇 |
2015年 | 15篇 |
2014年 | 21篇 |
2013年 | 47篇 |
2012年 | 26篇 |
2011年 | 27篇 |
2010年 | 21篇 |
2009年 | 16篇 |
2008年 | 22篇 |
2007年 | 15篇 |
2006年 | 23篇 |
2005年 | 14篇 |
2004年 | 15篇 |
2003年 | 16篇 |
2002年 | 12篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 4篇 |
1996年 | 3篇 |
1995年 | 6篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1978年 | 1篇 |
排序方式: 共有458条查询结果,搜索用时 265 毫秒
291.
Toxicology and detection methods of the alkaloid neurotoxin produced by cyanobacteria, anatoxin-a 总被引:1,自引:0,他引:1
Freshwater resources are under stress due to naturally occurring conditions and human impacts. One of the consequences is the proliferation of cyanobacteria, microphytoplankton organisms that are capable to produce toxins called cyanotoxins. Anatoxin-a is one of the main cyanotoxins. It is a very potent neurotoxin that was already responsible for some animal fatalities. In this review we endeavor to divulgate much of the internationally published information about toxicology, occurrence and detection methods of anatoxin-a. Cyanobacteria generalities, anatoxin-a occurrence and production as well as anatoxin-a toxicology and its methods of detection are the aspects focused in this review. Remediation of anatoxin-a occurrence will be addressed with a public health perspective. Final remarks call the attention for some important gaps in the knowledge about this neurotoxin and its implication to public health. Alterations of aquatic ecosystems caused by anatoxin-a is also addressed. Although anatoxin-a is not the more frequent cyanotoxin worldwide, it has to be regarded as a health risk that can be fatal to terrestrial and aquatic organisms because of its high toxicity. 相似文献
292.
293.
Erik Stenvall Sandra Tostar Antal Boldizar Mark R.StJ. Foreman Kenneth Möller 《Waste management (New York, N.Y.)》2013,33(4):915-922
The compositions of three WEEE plastic batches of different origin were investigated using infrared spectroscopy, and the metal content was determined with inductively coupled plasma. The composition analysis of the plastics was based mainly on 14 samples collected from a real waste stream, and showed that the major constituents were high impact polystyrene (42 wt%), acrylonitrile–butadiene–styrene copolymer (38 wt%) and polypropylene (10 wt%). Their respective standard deviations were 21.4%, 16.5% and 60.7%, indicating a considerable variation even within a single batch. The level of metal particle contamination was found to be low in all samples, whereas wood contamination and rubber contamination were found to be about 1 wt% each in most samples. In the metal content analysis, iron was detected at levels up to 700 ppm in the recyclable waste plastics fraction, which is of concern due to its potential to catalyse redox reactions during melt processing and thus accelerate the degradation of plastics during recycling. Toxic metals were found only at very low concentrations, with the exception of lead and cadmium which could be detected at 200 ppm and 70 ppm levels, respectively, but these values are below the current threshold limits of 1000 ppm and 100 ppm set by the Restriction of Hazardous Substances directive. 相似文献
294.
Despite its negative effects, formalin has been often used for the expulsion of earthworms due to its high efficiency; however it is not known whether it will affect any significant measurable molecular processes in sampled earthworms. The aim of this research was to investigate effects of formalin on the activities of chosen molecular biomarkers in Eisenia andrei earthworms previously exposed to temephos. Additionally, the inhibitory effect of temephos, hitherto evaluated only on laboratory-bred earthworm species, was confirmed on two earthworm species obtained from their natural environment – Dendrobaena octaedra and Lumbricus rubellus. Earthworms were first exposed to the sub-lethal concentration of temephos for 2 h and then to formalin 15 min in order to simulate the sampling procedure. Besides acetylcholinesterase (AChE) inhibition – a known biomarker of exposure to organophosphate insecticides – the concentration of oximes and the activities of catalase (CAT) and efflux pump were measured. Results showed that in all species temephos caused inhibition of AChE and CAT activity. Exposure of E. andrei to formalin caused inhibition of AChE, however after post-exposure to formalin for 15 min significant increase in AChE activity was recorded. Similar results were obtained with the measurement of oximes concentrations. Exposure to only formalin and combination of temephos (2 h) and formalin (15 min) led to an increase in the CAT activity. The obtained results showed that exposure to formalin during the sampling could affect measured molecular biomarkers and also may change effects caused by exposure to temephos. 相似文献
295.
Iván N. Pérez-Maldonado Antonio Trejo-Acevedo Sandra Teresa Orta-García Ángeles C. Ochoa-Martinez José Antonio Varela-Silva Francisco Javier Pérez-Vázquez 《Journal of environmental science and health. Part. B》2013,48(2):87-93
The aim of this study was to assess the levels of dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethylene (DDE) in the blood of children living in the southeastern region of Mexico. In this study, we found high levels of DDT and its principal metabolite (DDE) in the blood of children residing in the communities studied. The levels of total DDT found in our study ranged from 4,676.4 ng/g lipid to 64,245.2 ng/g lipid. All of the children in the study had detectable levels of DDT and/or DDE. In conclusion, our data indicate that children living within the study areas are exposed to high levels of DDT and DDE. Moreover, these results can be used as a trigger to revisit local policies on environmental exposures. 相似文献
296.
297.
298.
299.
Spatial Targeting of Agri-Environmental Measures: Cost-Effectiveness and Distributional Consequences
Sandra Uthes Bettina Matzdorf Klaus Müller Harald Kaechele 《Environmental management》2010,46(3):494-509
Agri-environmental measures are payments to farmers to reduce environmental risks or to preserve cultivated landscapes. These
measures are codified in European Union regulations. Poor spatial targeting is one of the major causes of low cost-effectiveness
in agri-environmental measures. Existing studies on spatial targeting focus primarily on selected individual measures; hence,
they do not allow for conclusions at the program level, where the planning and implementing of decisions on a number of different
measures has to be made. In this study, we analyzed the impacts of two spatial targeting options (targeting of erosion-reducing
measures on erosion vulnerable areas; targeting of grassland extensification on N-pollution vulnerable areas) on the cost-effectiveness
of the single measures and the entire agri-environmental program of the federal state of Brandenburg in Germany. The methodological
steps included an analysis of empirical data on land use and program participation, an expert-based environmental impact assessment
and a spatial allocation procedure based on linear programming. The environmental impact assessment delivered goal-specific
index values for each measures-land parcel combination expressing the suitability of the measures for contributing to four
regionally relevant program objectives. The cost-effectiveness of the measures and the program were calculated by putting
budgetary costs in relation to the achieved environmental index sum. The calculated cost-effectiveness of the program in 2006
was 89.6% of the simulated optimal cost-effectiveness. The spatial targeting of erosion-reducing measures on erosion vulnerable
areas caused an increase in the cost-effectiveness at the measures level and almost no changes at the program level. The spatial
targeting of grassland extensification on N-pollution vulnerable areas, despite also improving the cost-effectiveness of this
measure, had negative effects on the cost-effectiveness of the program. 相似文献
300.
Lavorel Sandra Grigulis Karl Leitinger Georg Kohler Marina Schirpke Uta Tappeiner Ulrike 《Regional Environmental Change》2017,17(8):2251-2264
Regional Environmental Change - Land use and spatial patterns which reflect social-ecological legacies control ecosystem service (ES) supply. Yet, temporal changes in ES bundles associated with... 相似文献