全文获取类型
收费全文 | 8063篇 |
免费 | 119篇 |
国内免费 | 104篇 |
专业分类
安全科学 | 325篇 |
废物处理 | 289篇 |
环保管理 | 1276篇 |
综合类 | 1453篇 |
基础理论 | 1911篇 |
环境理论 | 6篇 |
污染及防治 | 1862篇 |
评价与监测 | 591篇 |
社会与环境 | 523篇 |
灾害及防治 | 50篇 |
出版年
2023年 | 49篇 |
2022年 | 77篇 |
2021年 | 111篇 |
2020年 | 87篇 |
2019年 | 103篇 |
2018年 | 144篇 |
2017年 | 176篇 |
2016年 | 227篇 |
2015年 | 163篇 |
2014年 | 252篇 |
2013年 | 670篇 |
2012年 | 303篇 |
2011年 | 411篇 |
2010年 | 303篇 |
2009年 | 360篇 |
2008年 | 368篇 |
2007年 | 389篇 |
2006年 | 346篇 |
2005年 | 298篇 |
2004年 | 267篇 |
2003年 | 265篇 |
2002年 | 253篇 |
2001年 | 232篇 |
2000年 | 165篇 |
1999年 | 129篇 |
1998年 | 80篇 |
1997年 | 106篇 |
1996年 | 77篇 |
1995年 | 108篇 |
1994年 | 89篇 |
1993年 | 81篇 |
1992年 | 77篇 |
1991年 | 68篇 |
1990年 | 78篇 |
1989年 | 67篇 |
1988年 | 50篇 |
1987年 | 48篇 |
1986年 | 41篇 |
1985年 | 56篇 |
1984年 | 45篇 |
1983年 | 67篇 |
1982年 | 48篇 |
1981年 | 73篇 |
1980年 | 50篇 |
1979年 | 48篇 |
1978年 | 36篇 |
1977年 | 30篇 |
1976年 | 34篇 |
1975年 | 31篇 |
1966年 | 27篇 |
排序方式: 共有8286条查询结果,搜索用时 15 毫秒
91.
The relationship between the principle of free trade and nature conservation is one of the most acute and multifaceted problems in international business. The diversity of WTO activities implies the necessity of interdisciplinary studies utilizing the expertise and experience of specialists in international law and ecologists. In this paper, provisions of the WTO set of agreements and procedures for dispute settlement within the WTO framework are considered as applied to environmental protection. 相似文献
92.
Both the ‘cascade model’ of ecosystem service provision and the Driver-Pressure-State-Impact-Response framework individually contribute to the understanding of human–nature interactions in social–ecological systems (SES). Yet, as several points of criticism show, they are limited analytical tools when it comes to reproducing complex cause–effect relationships in such systems. However, in this paper, we point out that by merging the two models, they can mutually enhance their comprehensiveness and overcome their individual conceptual deficits. Therefore we closed a cycle of ecosystem service provision and societal feedback by rethinking and reassembling the core elements of both models. That way, we established a causal sequence apt to describe the causes of change to SES, their effects and their consequences. Finally, to illustrate its functioning we exemplified and discussed our approach based on a case study conducted in the Alpujarra de la Sierra in southern Spain.
Electronic supplementary material
The online version of this article (doi:10.1007/s13280-015-0651-y) contains supplementary material, which is available to authorized users. 相似文献93.
Margaret O. James Kevin M. Kleinow 《Environmental science and pollution research international》2014,21(10):6324-6333
There is extensive evidence that fish from waters with polychlorinated biphenyls (PCB)-contaminated sediments accumulate PCBs and related chemicals and that people who eat fish from contaminated waters have higher body burdens of PCBs and PCB metabolites than those who do not. PCBs and their metabolites are potentially toxic; thus, it is important to human health to understand the uptake, biotransformation, and elimination of PCBs in fish since these processes determine the extent of accumulation. The intestinal uptake of PCBs present in the diet of fish into fish tissues is a process that is influenced by the lipid composition of the diet. Biotransformation of PCBs in fish, as in mammals, facilitates elimination, although many PCB congeners are recalcitrant to biotransformation in fish and mammals. Sequential biotransformation of PCBs by cytochrome P450 and conjugation pathways is even less efficient in fish than in mammalian species, thus contributing to the retention of PCBs in fish tissues. A very important factor influencing overall PCB disposition in fish is water temperature. Seasonal changes in water temperature produce adaptive physiological and biochemical changes in fish. While uptake of PCBs from the diet is similar in fish acclimated to winter or summer temperatures, there is evidence that elimination of PCBs occurs much more slowly when the fish is acclimated at low temperatures than at warmer temperatures. Research to date suggests that the processes of elimination of PCBs are modulated by several factors in fish including seasonal changes in water temperature. Thus, the body burden of PCBs in fish from a contaminated location is likely to vary with season. 相似文献
94.
Philip G. Crandall Steven C. Ricke Corliss A. O’Bryan Nicole M. Parrish 《Journal of environmental science and health. Part. B》2013,48(7):736-741
We evaluated the in vitro activity of citrus oils against Mycobacterium tuberculosis and other non-tuberculous Mycobacterium species. Citrus essential oils were tested against a variety of Mycobacterium species and strains using the BACTEC radiometric growth system. Cold pressed terpeneless Valencia oil (CPT) was further tested using the Wayne model of in vitro latency. Exposure of M. tuberculosis and M. bovis BCG to 0.025 % cold pressed terpeneless Valencia orange oil (CPT) resulted in a 3-log decrease in viable counts versus corresponding controls. Inhibition of various clinical isolates of the M. avium complex and M. abscessus ranged from 2.5 to 5.2-logs. Some species/strains were completely inhibited in the presence of CPT including one isolate each of the following: the M. avium complex, M. chelonae and M. avium subsp. paratuberculosis. CPT also inhibited the growth of BCG more than 99 % in an in vitro model of latency which mimics anaerobic dormancy thought to occur in vivo. The activity of CPT against drug-resistant strains of the M. avium complex and M. abscessus suggest that the mechanism of action for CPT is different than that of currently available drugs. Inhibition of latently adapted bacilli offers promise for treatment of latent infections of MTB. These results suggest that the antimycobacterial properties of CPT warrant further study to elucidate the specific mechanism of action and clarify the spectrum of activity. 相似文献
95.
96.
T.M. McIntire O.S. Ryder P.L. Gassman Z. Zhu S. Ghosal B.J. Finlayson-Pitts 《Atmospheric environment (Oxford, England : 1994)》2010,44(7):939-944
It is commonly assumed that atmospheric oxidation of hydrocarbon particles or hydrocarbon coatings on particles leads to polar products and increased water uptake, altering atmospheric visibility and increasing the likelihood they will act as cloud condensation nuclei (CCN). We show here through laboratory experiments that increased water uptake depends on the 3-dimensional structure of the particles. Laboratory studies of particles formed during ozonolysis of surface-bound alkenes, present as terminally unsaturated self-assembled monolayers (C8= SAM) on a silica substrate, were carried out at room temperature and 1 atm pressure. SAMs were exposed to ~1013 O3 molecules cm?3 for 40 min and resultant particles were analyzed using single particle Fourier transform infrared micro-spectroscopy (micro-FTIR) and secondary ion mass spectroscopy (SIMS). Spectroscopy results show that –COOH and other polar groups are formed but are buried inside a hydrophobic shell, consistent with earlier observations (McIntire et al., 2005, Moussa et al., 2009) that water uptake does not increase after reaction of the terminal alkene with O3. These insights into the 3-D structure of particles formed on oxidation have important implications for the ability of secondary organic aerosols to act as CCN. In addition, the nature of the surface of the particles is expected to determine their uptake into biological systems such as the surface of the lungs. 相似文献
97.
Hardiljeet K. Boparai Meera Joseph Denis M. O’Carroll 《Environmental science and pollution research international》2013,20(9):6210-6221
Nano zerovalent iron (nZVI) is an effective remediant for removing various organic and inorganic pollutants from contaminated water sources. Batch experiments were conducted to characterize the nZVI surface and to investigate the effects of various solution properties such as pH, initial cadmium concentration, sorbent dosage, ionic strength, and competitive ions on cadmium removal by nZVI. Energy-dispersive X-ray and X-ray photoelectron spectroscopy results confirmed removal of Cd2+ ions by nZVI through adsorption. Cd2+ adsorption decreased in the presence of competitive cations in the order: Zn2+?>?Co2+?>?Mg2+?>?Mn2+?=?Cu2+?>?Ca2+?>?Na2+?=?K+. Higher concentrations of Cl? significantly decreased the adsorption. Cadmium removal increased with solution pH and reached a maximum at pH 8.0. The effects of various solution properties indicated Cd2+ adsorption on nZVI to be a chemisorption (inner-sphere complexation) process. The three surface complexation models (diffuse layer model, constant capacitance model, and triple layer model) fitted well to the adsorption edge experimental data indicating the formation of nZVI–Cd bidentate inner-sphere surface complexes. Our results suggest that nZVI can be effectively used for the removal of cadmium from contaminated water sources with varying chemical conditions. 相似文献
98.
Anthropogenic effects such as contamination affect the genetic structure of populations. This study examined the temporal and geographical patterns of genetic diversity among populations of the benthic crustacean amphipod Melita plumulosa in the Parramatta River (Sydney, Australia), following an industrial chemical spill. The spill of an acrylate/methacrylate co-polymer in naphtha solvent occurred in July 2006. M. plumulosa were sampled temporally between December 2006 and November 2009 and spatially in November 2009. Genetic variation was examined at the mitochondrial cytochrome c oxidase subunit I locus. Notably, nucleotide diversity was low and Tajima’s D was significantly negative amongst amphipods collected immediately downstream from the spill for 10 months. We hypothesize that the spill had a significant localized effect on the genetic diversity of M. plumulosa. Alternate explanations include an alternate and unknown toxicant or a localized sampling bias. Future proposed studies will dissect these alternatives. 相似文献
99.
100.
Joy Romanski Anastasia Romanou Michael Bauer George Tselioudis 《Regional Environmental Change》2014,14(5):1713-1723
We analyze daily wintertime cyclone variability in the central and eastern Mediterranean during 1958–2001 and identify four distinct “cyclone states,” corresponding to the presence or absence of cyclones in each basin. Each cyclone state is associated with wind flows that induce characteristic patterns of cooling via turbulent (sensible and latent) heat fluxes in the eastern Mediterranean basin and Aegean Sea. The relative frequency of occurrence of each state determines the heat loss from the Aegean Sea during that winter, with largest heat losses occurring when there is a storm in the eastern but not central Mediterranean (eNOTc) and the smallest occurring when there is a storm in the central but not eastern Mediterranean (cNOTe). Time series of daily cyclone states for each winter allow us to infer Aegean Sea cooling for winters prior to 1985, the earliest year for which we have daily heat flux observations. We show that cyclone states conducive to Aegean Sea convection occurred in 1991/1992 and 1992/1993, the winters during which deepwater formation was observed in the Aegean Sea, and also during the mid-1970s and the winters of 1963/1964 and 1968/1969. We find that the eNOTc cyclone state is anticorrelated with the North Atlantic Oscillation (NAO) prior to 1977/1978. After 1977/1978, the cNOTe state is anticorrelated with both the NAO and the North Caspian Pattern, showing that the area of influence of large-scale atmospheric teleconnections on regional cyclone activity shifted from the eastern to the central Mediterranean during the late 1970s. A trend toward more frequent occurrence of the positive phase of the NAO produced less frequent cNOTe states since the late 1970s, increasing the number of days with strong cooling of the Aegean Sea surface waters. 相似文献