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661.
The Annual Energy Outlook forecasts published by the United States Energy Information Administration (EIA) of the Department of Energy are based on results from the National Energy Modeling system (NEMS). This paper compares NEMS, which is used only in the U.S., with the U.S. version of MARKAL-MACRO (USMM) model, which is used in more than thirty-five countries. The two models predict similar results for the base 1999 US Annual Energy Outlook (AEO), but their results with carbon constraints are quite different. The differences of the models and those of their predictions are explained. USMM can be used to provide an alternative and complementary approach to projections of renewable technologies penetration and their potential in reducing carbon dioxide emissions in the USA. 相似文献
662.
Damla Kaner Ayfer Saraç Bahire Filiz Şenkal 《Environmental geochemistry and health》2010,32(4):321-325
A new polymeric resin with amino sulfonic acid pendant functions has been prepared for the extraction of acidic and basic
dyes from water. Beaded polymer supports were prepared by suspension polymerization of vinyl benzyl chloride (0.9 mol) and
ethylene glycol dimethacrylate (0.1 mol). The resulting copolymer beads were modified with amino methane sulfonic acid. The
dye adsorption capacity of the resin was found as 0.16 g dye/g resin for ramazol black and 0.15 g dye/g resin for crystal
violet. The pH depending measurements and dye sorption kinetics of the resin were also investigated. 相似文献
663.
Alvin R. Morris 《环境质量管理》1991,1(1):31-35
By focusing on regulated businesses as “customers,” the EPA is bringing a new way of thinking to the negotiating table that is producing creative, workable solutions. The author, who was instrumental in initiating the adoption of TQM in the Environmental Protection Agency, discusses how it can be used in negotiation to resolve impasses between EPA and business and meet the needs of both. 相似文献
664.
Whole animal concentrations of Pb, Zn and Cd were measured in herbivorous (1 snail species; 1 dipteran larva species), herbivorous + detritivorous (2 slug species), detritivorous (3 woodlouse species; 3 earthworm species), and carnivorous (1 carabid beetle species; 1 lithobiid centipede species) terrestrial macroinvertebrates collected at a disused Pb/Zn mine site. No evidence was found for an accretion of any metal during transference from herbivores to carnivores; the highest metal concentrations were, in fact, generally found in detritivores. The lack of metal bio-amplification during food chain transference is probably due to the sequestration of metals (notably Pb and Zn) in insoluble inorganic-rich granules within certain target organs and cells.
Earthworms and woodlice, respectively, showed major differences in metal concentrations. These differences between closely related species frequently exceeded differences between unrelated species occupying different trophic levels, and may be attributable to a combination of ill-defined ecological and physiological differences that ensure habitat and resource partitioning. 相似文献
Earthworms and woodlice, respectively, showed major differences in metal concentrations. These differences between closely related species frequently exceeded differences between unrelated species occupying different trophic levels, and may be attributable to a combination of ill-defined ecological and physiological differences that ensure habitat and resource partitioning. 相似文献
665.
666.
Summary There is no consensus about the function of scent-rubbing, a widespread behaviour in which mammals rub their bodies vigorously in substances, many strong-smelling and some artificial, such as rotting meat, intestinal contents and engine oil. Here we suggest that scent-rubbing is involved in status advertisement and that, as in assessment using scent marks, the mechanism used by competitors to assess potential opponents may be scent-matching. In scent-matching a resource holder is assessed (identified) by comparing its odour with odours on or near the defended resource. In scent marking the odour originates from the resource holder (glandular secretion, urine and faeces); in scent-rubbing the odour originates in the environment.A prerequisite of unambiguous scent-matching is that the odour of scent-marks should be uniquely characteristic of one individual. This may be why marking substances are very complex chemically. Scent-rubbing often occurs with scent-marking and, rather than acting independently of scent-marking, the odours acquired may either (i) add to the complexity of the signal, thus reducing signal ambiguity, or (ii) increase the range of the signal by adding a strong smelling component.Subordinates could potentially cheat by rubbing in the same odours as the resource holder. Resource holders could prevent cheating (i) by checking other status cues and by testing competitors whose scent matches, then escalating contests when the competitor's fighting ability (more formally, Resource Holding Power) proves to be lower than that of a resource holder and (ii) by mixing the substances used for scent-rubbing with the unique substances used in scent-marking. 相似文献
667.
Nelson J. ODriscoll Emma Vost Erin Mann Sara Klapstein Robert Tordon Matthew Lukeman 《环境科学学报(英文版)》2018,30(6):151-159
Mercury is a globally distributed, environmental contaminant. Quantifying the retention and loss of mercury is integral for predicting mercury-sensitive ecosystems. There is little information on how dissolved organic carbon(DOC) concentrations and particulates affect mercury photoreaction kinetics in freshwater lakes. To address this knowledge gap,samples were collected from ten lakes in Kejimkujik National Park, Nova Scotia(DOC: 2.6–15.4 mg/L). Filtered(0.2 μm) and unfiltered samples were analysed for gross photoreduction, gross photooxidation, and net reduction rates of mercury using pseudo first-order curves. Unfiltered samples had higher concentrations(p = 0.04) of photoreducible divalent mercury(Hg(II)RED)(mean of 754 ± 253 pg/L) than filtered samples(mean of 482 ± 206 pg/L);however, gross photoreduction and photooxidation rate constants were not significantly different in filtered or unfiltered samples in early summer. DOC was not significantly related to gross photoreduction rate constants in filtered(R~2= 0.43; p = 0.08) and unfiltered(R~2= 0.02; p = 0.71) samples; DOC was also not significantly related to gross photooxidation rate constants in filtered or unfiltered samples. However, DOC was significantly negatively related with Hg(Ⅱ)_(RED) in unfiltered(R2= 0.53; p = 0.04), but not in filtered samples(R~2= 0.04;p = 0.60). These trends indicate that DOC is a factor in determining dissolved mercury photoreduction rates and particles partially control available Hg(Ⅱ)_(RED) in lake water. This research also demonstrates that within these lakes gross photoreduction and photooxidation processes are close to being in balance. Changes to catchment inputs of particulate matter and DOC may alter mercury retention in these lakes and could partially explain observed increases of mercury accumulation in biota. 相似文献
668.
Francesca Pennino Antonio Nardone Paolo Montuori Sara Aurino Ida Torre Andrea Battistone Roberto Delogu Gabriele Buttinelli Stefano Fiore Concetta Amato Maria Triassi 《Food and environmental virology》2018,10(2):187-192
Human enteroviruses (HEVs) occur in high concentrations in wastewater and can contaminate receiving environmental waters, constituting a major cause of acute waterborne disease worldwide. In this study, we investigated the relative abundance, occurrence, and seasonal distribution of polio and other enteroviruses at three wastewater treatment plants (WWTPs) in Naples, Southern Italy, from January 2010 to December 2014. Influent and effluent samples from the three WWTPs were collected monthly. One hundred and sixty-one of the 731 wastewater samples collected (22.0%) before and after water treatment were CPE positive on RD cells; while no samples were positive on L20B cells from any WWTPs. Among the 140 non-polio enterovirus isolated from inlet sewage, 69.3% were Coxsackieviruses type B and 30.7% were Echoviruses. Among these, CVB3 and CVB5 were most prevalent, followed by CVB4 and Echo6. The twenty-one samples tested after treatment contained 6 CVB4, 5 CVB3, 3 Echo11, and 2 Echo6; while other serotypes were isolated less frequently. Data on viral detection in treated effluents of WWTPs confirmed the potential environmental contamination by HEVs and could be useful to establish standards for policies on wastewater management. 相似文献
669.
Michael C. Morris 《Journal of Agricultural and Environmental Ethics》2006,19(5):495-514
Changes in attitudes toward animal welfare, with a greater emphasis on the importance of allowing animals to express normal patterns of behavior has led to an examination of the practice of keeping hens in battery cages. There is widespread scientific consensus that the conditions of confinement and the barren nature of battery cages severely restrict hens’ behavioral repertoire, and are thus detrimental to their welfare. The New Zealand Animal Welfare Act 1999, stipulates that animals must have “the opportunity to display normal patterns of behaviour.” In spite of this provision, the New Zealand government has not acted in phasing out battery cages, arguing instead that there is insufficient evidence that welfare will be improved by a phase-out. There is evidence of strong industry pressure on the government, and the use of tactics common in policy considerations where changes are resisted by powerful interests. It is important that policy processes are better managed so that welfare changes are based on both public preferences and scientific knowledge, and ways of doing this are discussed. 相似文献
670.
Measured gas emissions from four landfills in south africa and some implications for landfill design and methane recovery in semi-arid climates. 总被引:1,自引:0,他引:1
The magnitude of annual global emissions of methane from municipal solid waste landfills without landfill gas control systems implies that these landfills are significant contributors to the atmospheric load of greenhouse gases. There have been a number of field studies undertaken internationally to measure actual fluxes of methane and carbon dioxide from landfills, with a view to corroborating modelled predictions of the contribution of landfills to the global greenhouse gas budget. The vast majority of these studies have been undertaken in more temperate climates and in developed countries. This paper reports a study of landfill gas emissions from four large landfills located in the semi-arid interior of South Africa. A static accumulation chamber was used and measurements were made at each site over a period of two to three days. The results were analysed by three different methods, all of them leading to the same general conclusion that landfill gas emission rates were lower than expected. A common conclusion based on results from all four sites was that capping of landfills in semi-arid climates with low permeability covers would probably significantly retard the already low rate of waste degradation and thus gas generation. While this may be regarded as advantageous in the short term, it cannot be relied upon in perpetuity as clayey landfill covers will inevitably desiccate and crack in a semiarid environment. In addition, reasonable after-care periods for such landfills are likely to extend well beyond the currently stipulated 30-year period, and efforts to encourage energy recovery from landfills may be hampered because gas generation rates decrease as the waste dries out under conditions of minimal recharge from precipitation. A landfill cover that allows small amounts of percolation of rainfall into the waste may therefore in fact be beneficial in semiarid climates, although care would need to be taken to carefully regulate this infiltration. 相似文献