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31.
Research across several decades has mapped the way complex environmental issues with complicated policy implications are often differentially framed within the media, public, and policy agendas with major implications for how they are understood, discussed, and decided. Building on this work, this this study compared news coverage of the debate over natural gas “fracking” in New York, Pennsylvania, and North Carolina between the period 2008 and 2013. Examining state newspapers, the analysis evaluated the types of sources used, the assertions of these sources, and how the issue of fracking was framed. From a general perspective, this study reveals how differences in framing of an environmental and scientific controversy can be attributed to the locally relevant sources used in reporting, as well as the political, economic, and social factors that might be unique to a state. Specific to the debate over natural gas “fracking,” this study adds to our understanding of how such state-based factors influence the portrayal of the issue in the news media. 相似文献
32.
A survey-embedded experiment implemented around the time of the 2014 annual Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (N ≈ 1200) examined whether such summits are able to increase citizens’ awareness of climate problems. This study finds that exposure to positive or negative cues about the COP increases climate change awareness, particularly among participants who start out with a low level of awareness. Neither positive nor negative cues about the COP significantly affect people’s policy preferences. Our finding resonates with Bernard Cohen’s observation that the mass media may not often be successful in telling people what to think, but they are successful in telling readers what to think about. 相似文献
33.
Mari Luz García-Lorenzo María José Martínez-Sánchez Carmen Pérez-Sirvent Joaquín López-Sánchez José Molina-Ruiz Mari Luz Tudela 《Environmental Forensics》2015,16(1):88-95
The objective of this study was to determine the As and Sb contents in soils from the Murcia Region of Spain and the possible relationship between the mineralogical composition, soil properties, and As and Sb concentrations. In this study, 490 samples were selected from areas with different characteristics in order to study As and Sb variability. Results show that As and Sb concentrations are positively correlated with the phyllosilicate and quartz content but negatively correlated with the calcite content. The generic reference level (GRL) for these elements was determined according to the Spanish legislation. Established GRL values vary according to the established mineralogical groups, suggesting that GRL has to be determined considering the lithological characteristics of the study area. 相似文献
34.
Jeff Joireman Heather Barnes Truelove Blythe Duell 《Journal of environmental psychology》2010,30(4):358-367
It is generally acknowledged that global warming is occurring, yet estimates of future climate change vary widely. Given this uncertainty, when asked about climate change, it is likely that people’s judgments may be affected by heuristics and accessible schemas. Three studies evaluated this proposition. Study 1 revealed a significant positive correlation between the outdoor temperature and beliefs in global warming. Study 2 showed that people were more likely to believe in global warming when they had first been primed with heat-related cognitions. Study 3 demonstrated that people were more likely to believe in global warming and more willing to pay to reduce global warming when they had first been exposed to a high vs. a low anchor for future increases in temperature. Together, results reveal that beliefs about global warming (and willingness to take actions to reduce global warming) are influenced by heuristics and accessible schemas. Several practical implications are discussed. 相似文献
35.
36.
Vera Garaj-Vrhovac Višnja Oreščanin Goran Gajski Marko Gerić Damir Ruk Robert Kollar Sandra Radić Brkanac Petra Cvjetko 《Chemosphere》2013
In this research, toxicological safety of two newly developed methods for the treatment of landfill leachate from the Piškornica (Croatia) sanitary landfill was investigated. Chemical treatment procedure combined chemical precipitation with CaO followed by coagulation with ferric chloride and final adsorption by clinoptilolite. Electrochemical treatment approach included pretreatment with ozone followed by electrooxidation/electrocoagulation and final polishing by microwave irradiation. Cell viability of untreated/treated landfill leachate was examined using fluorescence microscopy. Cytotoxic effect of the original leachate was obtained for both exposure periods (4 and 24 h) while treated samples showed no cytotoxic effect even after prolonged exposure time. The potential DNA damage of the untreated/treated landfill leachate was evaluated by the comet assay and cytokinesis-block micronucleus (CBMN) assay using either human or plant cells. The original leachate exhibited significantly higher comet assay parameters compared to negative control after 24 h exposure. On the contrary, there was no significant difference between negative control and chemically/electrochemically treated leachate for any of the parameters tested. There was also no significant increase in either CBMN assay parameter compared to the negative control following the exposure of the lymphocytes to the chemically or electrochemically treated landfill leachate for both exposure periods while the original sample showed significantly higher number of micronuclei, nucleoplasmic bridges and nuclear buds for both exposure times. Results suggest that both methods are suitable for the treatment of such complex waste effluent due to high removal efficiency of all measured parameters and toxicological safety of the treated effluent. 相似文献
37.
Policy and research issues in the framing and qualities of uncertainties in risks are analyzed, based on the assessments of
dioxin-like compounds (DLCs) and other ingredients in Baltic Sea fish, a high-profile case of governance. Risks are framed
broadly, to then focus on dioxins and beneficial fatty acids, fish consumption, human health, and science-management links.
Hierarchies of uncertainty (data, model, decision rule, and epistemic) and ambiguity (of values) are used to identify issues
of scientific and policy contestation and opportunities for resolving them. The associated complexity of risks is illustrated
by risk–benefit analyses of fish consumption and by evaluations of guideline values, highlighting value contents and policy
factors in presumably scientific decision criteria, and arguments used in multi-dimensional risk and benefit comparisons.
These comparisons pose challenges to narrow assessments centered, for e.g., on toxicants or on food benefits, and to more
many-sided and balanced risk communication and management. It is shown that structured and contextualized treatment of uncertainties
and ambiguities in a reflexive approach can inform balances between wide and narrow focus, detail and generality, and evidence
and precaution. 相似文献
38.
Real C Ángel Fernández J Aboal JR Carballeira A 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2797-2800
Multivariate analysis of environmental data sets requires the absence of missing values or their substitution by small values. However, if the data is transformed logarithmically prior to the analysis, this solution cannot be applied because the logarithm of a small value might become an outlier. Several methods for substituting the missing values can be found in the literature although none of them guarantees that no distortion of the structure of the data set is produced. We propose a method for the assessment of these distortions which can be used for deciding whether to retain or not the samples or variables containing missing values and for the investigation of the performance of different substitution techniques. The method analyzes the structure of the distances among samples using Mantel tests. We present an application of the method to PCDD/F data measured in samples of terrestrial moss as part of a biomonitoring study. 相似文献
39.
In addition to providing key ecological functions, large old trees are a part of a social realm and as such provide numerous social‐cultural benefits to people. However, their social and cultural values are often neglected when designing conservation policies and management guidelines. We believe that awareness of large old trees as a part of human identity and cultural heritage is essential when addressing the issue of their decline worldwide. Large old trees provide humans with aesthetic, symbolic, religious, and historic values, as well as concrete tangible benefits, such as leaves, branches, or nuts. In many cultures particularly large trees are treated with reverence. Also, contemporary popular culture utilizes the image of trees as sentient beings and builds on the ancient myths that attribute great powers to large trees. Although the social and cultural role of large old trees is usually not taken into account in conservation, accounting for human‐related values of these trees is an important part of conservation policy because it may strengthen conservation by highlighting the potential synergies in protecting ecological and social values. Incorporación del Significado Social y Cultural de Árboles Añejos a Políticas de Conservación 相似文献
40.
Ernest A. Meyer Joe Glicker Alan K. Bingham Roger Edwards 《Journal of the American Water Resources Association》1989,25(2):335-340
ABSTRACT: In a study to measure the efficacy of chioramines at inactivating Giardia cysts, the ability of cysts to excyst was measured after exposure to different concentrations of chloramines, for different times, and at different temperatures and pH. The chloramines were generated by mixing ammonium sulfate and sodium hypochlorate in water to approximate a 7:1 chlorine:ammonia ratio by weight. Times of 40, 80, 180, and 270 minutes; temperatures of 3, 10, and 18°C; target chioramine concentrations of 0.4, 1.4, 2.0, and 2.6 mg/L; and pH of 7.0 and 8.5 were the actual values tested. The combinations of these variables that were able to inactivate >99.8 percent of the cysts were a minimum chloramine concentration of 2.26 mg/L applied for 270 minutes at a water temperature of 10°C; and at 18°C, averaged minimum chloramine concentrations of 2.14 and 1.55 mg/L applied for 180 and 270 minutes, respectively. The minimum CT values corresponding to these combinations capable of >99.8 percent cyst inactivation, are 610 at 10°C and 385 at 18°C. Temperature was noted to exert a major effect on the ability of chloramines to inactivate cysts. Modifications of the methods used to generate chloramines may have an effect on the capacity of this disinfectant to inactivate cysts. 相似文献