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931.
Vijgen J Abhilash PC Li YF Lal R Forter M Torres J Singh N Yunus M Tian C Schäffer A Weber R 《Environmental science and pollution research international》2011,18(2):152-162
Purpose
Hexachlorocyclohexane (HCH) isomers (??-, ??- and ??- (Lindane)) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention, and therefore, the legacy of HCH and Lindane production became a contemporary topic of global relevance. This article wants to briefly summarise the outcomes of the Stockholm Convention process and make an estimation of the amount of HCH waste generated and dumped in the former Lindane/HCH-producing countries.Results
In a preliminary assessment, the countries and the respective amount of HCH residues stored and deposited from Lindane production are estimated. Between 4 and 7 million tonnes of wastes of toxic, persistent and bioaccumulative residues (largely consisting of alpha- (approx. 80%) and beta-HCH) are estimated to have been produced and discarded around the globe during 60 years of Lindane production. For approximately 1.9 million tonnes, information is available regarding deposition. Countries are: Austria, Brazil, China, Czech Republic, France, Germany, Hungary, India, Italy, Japan, Macedonia, Nigeria, Poland, Romania, Slovakia, South Africa, Spain, Switzerland, Turkey, The Netherlands, UK, USA, and former USSR. The paper highlights the environmental relevance of deposited HCH wastes and the related POPs?? contaminated sites and provides suggestions for further steps to address the challenge of the legacy of HCH/Lindane production.Conclusion
It can be expected that most locations where HCH waste was discarded/stockpiled are not secured and that critical environmental impacts are resulting from leaching and volatilisation. As parties to the Stockholm Convention are legally required to take action to stop further POPs pollution, identification and evaluation of such sites are necessary. 相似文献932.
Matilda Palm Madelene Ostwald Indu K. Murthy Rajiv K. Chaturvedi N. H. Ravindranath 《Regional Environmental Change》2011,11(2):423-435
This paper analyses environmental and socio-economic barriers for plantation activities on local and regional level and investigates
the potential for carbon finance to stimulate the increased rates of forest plantation on wasteland, i.e., degraded lands,
in southern India. Building on multidisciplinary field work and results from the model GCOMAP, the aim is to (1) identify
and characterize the barriers to plantation activities in four agro-ecological zones in the state of Karnataka and (2) investigate
what would be required to overcome these barriers and enhance the plantation rate and productivity. The results show that
a rehabilitation of the wasteland based on plantation activities is not only possible but also anticipated by the local population
and would lead to positive environmental and socio-economic effects at a local level. However, in many cases, the establishment
of plantation activities is hindered by a lack of financial resources, low land productivity and water scarcity. Based on
the model used and the results from the field work, it can be concluded that certified emission reductions such as carbon
credits or other compensatory systems may help to overcome the financial barrier; however, the price needs to be significantly
increased if these measures are to have any large-scale impact. 相似文献
933.
P. Valkering R. van der Brugge A. Offermans N. Rijkens-Klomp 《Regional Environmental Change》2011,11(2):229-241
Climate adaptation is a complex task surrounded by uncertainty. To support climate adaptation policies, a new scenario approach
is pursued to explore possible discontinuous future developments of societal perspectives on climate adaptation issues. The
scenario approach was tested for a case study on Dutch river management. In a series of scenario development workshops, a
select group of stakeholders explored the perspectives on the management of the River Meuse in the past, present, and future.
The process was supported by an analytical perspectives mapping tool to illustrate and analyze the development of perspectives
over time. The process and analytical tools contributed to insight into the drivers of perspective change for the case study
at hand. Moreover, the stakeholders highlighted the potential of the approach for water management policy for creating awareness
about the plurality of perspectives and the dynamics of perspective change, monitoring perspectives and perspective change
as part of a flexible policy approach, and anticipating on the occurrence of shock events. Further work is required to better
represent the social dynamics of perspectives change, to better empirically ground the perspective change model, and to apply
integrated water models in the scenario development process to assess water–society interactions. 相似文献
934.
The states of the populations of five dominant species of predatory mammals living in the area affected by the Kalinin Nuclear
Power Plant (NPP) and in remote districts of Tver’ oblast have been compared. A total of 1120 skulls, including 708 skulls
from the vicinity of the NPP, have been examined. The data on parameters characterizing similarities between the samples,
the degree and structure of intrapopulation diversity, and ontogenetic stability suggest with a high probability that the
Kalinin NPP has no effect on wild populations of predatory mammals. 相似文献
935.
V. V. Rozhnov E. Yu. Zvychainaya A. N. Kuksin A. D. Poyarkov 《Russian Journal of Ecology》2011,42(6):439-444
Molecular genetic methods were used to perform the species and individual identification of 117 samples of hair and feces
of carnivores collected in natural habitats. The species were identified for 85.5% of the samples. The analysis of the nucleotide
sequences of the cytochrome b mitochondrial gene was used to identify the samples of hair and feces of snow leopards (Uncia uncia, 40%), red foxes (Vulpes vulpes, 48%), wolves (Canis lupus, 6%), and lynx (Lynx lynx, 5%). The analysis of eight microsatellite loci allowed the genotypes of 13 snow leopards to be described. The sex of 11
animals was identified. 相似文献
936.
The results of studies on the radial increment of larch and pine in central Yakutia are presented. The application of dendroclimatological
methods to the study of tree-ring chronologies has made it possible to evaluate tree growth response to the dynamics of climatic
factors over the past 120 years. The results of analysis of radial tree increment show that the onset of the growing season
has shifted to earlier dates by the end of the 20th century. 相似文献
937.
Concerns regarding the impacts of pesticides on aquatic species and drinking water sources have increased demands on water quality monitoring programs; however the costs of sample analysis can be prohibitive. In this study we investigated enzyme-linked immunosorbent assay (ELISA) as a cost-effective, high through-put method for measuring pesticide concentrations in surface waters. Seven hundred and thirty-nine samples from 158 locations throughout Ontario were analysed for atrazine and metolachlor from April to October 2007. Concentrations ranged from <0.1 to 3.91 μg L−1 (median = 0.12 μg L−1) for atrazine and from <0.1 to 1.83 μg L−1 (median = 0.09 μg L−1) for metolachlor. Peak concentrations occurred in late spring/early summer, in rural agricultural locations, and decreased over the remainder of the growing season for both herbicides. About 3% of the samples that had ELISA results occurring above the limit of quantification (0.10 μg L−1) were evaluated against gas chromatography-mass spectrometry (GC-MS). Linear regression analysis revealed a R2 value of 0.88 and 0.39, for atrazine and metolachlor, respectively. ELISA tended to overestimate concentrations for atrazine and metolachlor, most likely because the ELISA kits also detect their metabolites. Atrazine data suggest that ELISA may be used complementary with GC-MS analysis to enhance the spatial and temporal resolution of a water quality monitoring study. The commercially available metolachlor ELISA kit requires further investigation. ELISA may be used to detect atrazine and metolachlor in surface water samples, but it is not recommended as a quantitative replacement for traditional analytical methods. 相似文献
938.
Bouo FX Kouamé JK Tchétché Y Kré RN Moussé ML Assamoi P Cautenet S Cautenet G 《Chemosphere》2011,84(11):1617-1629
The purpose of this paper is to study the redistribution of chemical species (OH, HO2, H2O2, HNO3 and H2SO4) over West Africa, where the cloud cover is ubiquitously present, and where deep convection often develops. In this area, because of these cloud systems, chemical species are redistributed by the ascending and descending flow, or leached if they are soluble. So, we carry out a mesoscale study using the Regional Atmospheric Modelling System (RAMS) coupled to a code of gas and aqueous chemistry (RAMS_Chemistry). It takes into account all processes under mesh. We examine several cases following the period (November and July), with inputs emissions (anthropogenic, biogenic and biomass burning). The radicals OH and HO2 are an indicator of possibilities for chemical activity. They characterize the oxidizing power of the atmosphere and are very strong oxidants. The acids HNO3 and H2SO4 are interesting in their transformation into nitrates and sulfates in precipitation. In November, when photochemistry is active during an event of biomass burning, concentrations of chemical species are higher than those of November in the absence of biomass burning. The concentrations of nitric acid double and sulfuric acid increases 70 times. In addition, the concentrations are even lower in July if there is a deep convection. Compared to measures of the African Monsoon Multidisciplinary Analysis (AMMA), the results and observations of radicals OH and HO2 are the same order of magnitude. Emissions from biomass burning increase the concentrations of acid and peroxide, and a deep convection cloud allows the solubility and the washing out of species, reducing their concentration. Rainfalls play a major role in solubility and washing out acids, peroxides and radicals in this region. 相似文献
939.
Many professionals in the environmental industry have questioned whether the rapid expansion in shale gas development, particularly in the Marcellus Shale Play, is providing business opportunities. While gas production is a routine practice, the development of shale gas requires a process (fracturing, or, more commonly, “fracing'') that uses chemicals and is far more intrusive to the subsurface environment than traditional gas production. In this Editor's Perspective, we evaluate the environmental issues surrounding shale gas development, with a specific focus on the Marcellus Shale Play because it is currently the most active play in the United States, from both the drilling and political perspectives. In addition, we examine where the business opportunities are likely to be for environmental professionals relative to shale gas development. © 2011 Wiley Periodicals, Inc. 相似文献
940.
N. Mithil Kumar K. Varaprasad G. Ramachandra Reddy G. Siva Mohan Reddy Y. Sivabharathi G. Venkata Subba Reddy S. Venkata Naidu 《Journal of Polymers and the Environment》2011,19(1):225-229
Synthesis and characterization of novel biodegradable, water soluble and optically active DL-malic acid (DMA) and citric acid
(CA) copolymers were studied for possible use as antibacterial agents. The copolymers were synthesized by direct bulk melt
condensation in the absence of a catalyst above 150 °C. Characterization of obtained copolymers was carried out with the help
of infrared absorption spectra, differential scanning calorimetry and thermo gravimetric analysis. The antibacterial activity
of copolymers against bacteria was investigated. The results obtained shows the above copolymers possess a broad wound dressing
activity against different types of bacteria and may be useful as antibacterial agents. 相似文献