全文获取类型
收费全文 | 300篇 |
免费 | 4篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 23篇 |
环保管理 | 46篇 |
综合类 | 24篇 |
基础理论 | 77篇 |
污染及防治 | 89篇 |
评价与监测 | 18篇 |
社会与环境 | 11篇 |
灾害及防治 | 3篇 |
出版年
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 10篇 |
2016年 | 7篇 |
2015年 | 3篇 |
2014年 | 10篇 |
2013年 | 24篇 |
2012年 | 8篇 |
2011年 | 28篇 |
2010年 | 15篇 |
2009年 | 9篇 |
2008年 | 14篇 |
2007年 | 16篇 |
2006年 | 22篇 |
2005年 | 10篇 |
2004年 | 11篇 |
2003年 | 9篇 |
2002年 | 12篇 |
2001年 | 19篇 |
2000年 | 5篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1983年 | 3篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1975年 | 1篇 |
1958年 | 2篇 |
1954年 | 1篇 |
1948年 | 1篇 |
1933年 | 1篇 |
1928年 | 2篇 |
1927年 | 1篇 |
1924年 | 1篇 |
排序方式: 共有305条查询结果,搜索用时 15 毫秒
261.
262.
Andersson KG Nielsen SP Thørring H Hansen HS Joensen HP Isaksson M Kostiainen E Suolanen V Pálsson SE 《Journal of environmental radioactivity》2011,102(11):1024-1031
The ECOSYS model is the ingestion dose model integrated in the ARGOS and RODOS decision support systems for nuclear emergency management. The parameters used in this model have however not been updated in recent years, where the level of knowledge on various environmental processes has increased considerably. A Nordic work group has carried out a series of evaluations of the general validity of current ECOSYS default parameters. This paper specifically discusses the parameter revisions required with respect to the modelling of deposition and natural weathering of contaminants on agricultural crops, to enable the trustworthy prognostic modelling that is essential to ensure justification and optimisation of countermeasure strategies. New modelling approaches are outlined, since it was found that current ECOSYS approaches for deposition and natural weathering could lead to large prognostic errors. 相似文献
263.
Olav R. Hansen Filippo Gavelli Mathieu Ichard Scott G. Davis 《Journal of Loss Prevention in the Process Industries》2010,23(6):857-877
The siting of facilities handling liquefied natural gas (LNG), whether for liquefaction, storage or regasification purposes, requires the hazards from potential releases to be evaluated. One of the consequences of an LNG release is the creation of a flammable vapor cloud, that may be pushed beyond the facility boundaries by the wind and thus present a hazard to the public. Therefore, numerical models are required to determine the footprint that may be covered by a flammable vapor cloud as a result of an LNG release. Several new models have been used in recent years for this type of simulations. This prompted the development of the “Model evaluation protocol for LNG vapor dispersion models” (MEP): a procedure aimed at evaluating quantitatively the ability of a model to accurately predict the dispersion of an LNG vapor cloud.This paper summarizes the MEP requirements and presents the results obtained from the application of the MEP to a computational fluid dynamics (CFD) model – FLACS. The entire set of 33 experiments included in the model validation database were simulated using FLACS. The simulation results are reported and compared with the experimental data. A set of statistical performance measures are calculated based on the FLACS simulation results and compared with the acceptability criteria established in the MEP. The results of the evaluation demonstrate that FLACS can be considered a suitable model to accurately simulate the dispersion of vapor from an LNG release. 相似文献
264.
The present work was performed to investigate the use of odorant measurements for prediction of odor concentration in facilities with growing-finishing pigs and to analyze the odorant composition in facilities with different floor and ventilation systems. Air was sampled in Nalophan bags, odor concentrations were measured by dilution-to-threshold olfactometry, and concentrations of odorants were measured by proton-transfer-reaction mass spectrometry (PTR-MS). Olfactometry and chemical analyses were synchronized to take place at identical time intervals after sampling. A principal component analysis revealed that different facilities for growing-finishing pigs can be distinguished based on the odorants. Pit ventilation comprising a small amount of the total ventilation air (10-20%) in facilities with both room and pit ventilation can be used to concentrate odorants, whereas the room ventilation contains lower concentrations of most odorants. A partial least squares regression model demonstrated that prediction of the odor concentration based on odorants measured by PTR-MS is feasible. Hydrogen sulfide, methanethiol, trimethylamine, and 4-methylphenol were identified as the compounds having the largest influence on the prediction of odor concentration, whereas carboxylic acids had no significant influence. In conclusion, chemical measurement of odorants by PTR-MS is an alternative for expressing the odor concentration in facilities with growing-finishing pigs that can be used to increase the understanding of odor from different types of facilities and improve the development of odor reduction technologies. 相似文献
265.
Mads Peter Heide-Jørgensen Louise M. Burt Rikke Guldborg Hansen Nynne Hjort Nielsen Marianne Rasmussen Sabrina Fossette Harry Stern 《Ambio》2013,42(5):596-610
The North Water polynya (~76°N to 79°N and 70°W to 80°W) is known to be an important habitat for several species of marine mammals and sea birds. For millennia, it has provided the basis for subsistence hunting and human presence in the northernmost part of Baffin Bay. The abundance of air-breathing top predators also represents a potential source of nutrient cycling that maintains primary production. In this study, aerial surveys conducted in 2009 and 2010 were used for the first time to map the distribution and estimate the abundance of top predators during spring in the North Water. Belugas (Delphinapterus leucas) were not detected north of 77°20′N but were found along the coast of West Greenland and offshore in the middle of the North Water with an abundance estimated at 2245 (95 % CI 1811–2783). Narwhals (Monodon monoceros) were widely distributed on the eastern side of the North Water with an estimate of abundance of 7726 (3761–15 870). Walruses (Odobenus rosmarus) were found across the North Water over both shallow and deep (>500 m) water with an estimated abundance of 1499 (1077–2087). Bearded (Erignathus barbatus) and ringed seals (Phoca hispida) used the large floes of ice in the southeastern part of the North Water for hauling out. Most polar bears (Ursus maritimus) were detected in the southern part of the polynya. The abundances of bearded and ringed seals were 6016 (3322–10 893) and 9529 (5460–16 632), respectively, and that of polar bears was 60 (12–292). Three sea bird species were distributed along the Greenland coast (eiders, Somateria spp.), in leads and cracks close to the Greenland coast (little auks, Alle alle) or widely in open water (thick-billed guillemots, Uria lomvia). 相似文献
266.
James F. Begley Eric Hansen Amanda K. Wells Samuel Fogel Gail S. Begley 《补救:环境净化治理成本、技术与工艺杂志》2009,20(1):107-117
Direct aerobic biodegradation of vinyl chloride (VC) offers a remedial solution for persistent vinyl chloride plumes that are not amenable to the anaerobic process of reductive dechlorination because of either prevailing geochemical conditions or the absence of active Dehalococcoides ethenogenes. However, tools are needed to evaluate and optimize aerobic VC bioremediation. This article describes the development and testing of two techniques—a microbiological tool and a molecular tool—for this purpose. Both methods are based on detection of bacteria that can use vinyl chloride and ethene as growth substrates in the presence of oxygen. The microbiological tool is an activity assay that indicates whether bacteria capable of degrading ethene under aerobic conditions are present in a groundwater sample. This activity assay gave positive results in the area of active VC degradation of an aerobic VC bioremediation test site. A rapid semiquantitative genetic assay was also developed. This molecular tool, based on polymerase chain reaction (PCR) detection of a gene involved in the metabolism of both ethene and VC, revealed the presence of potential VC degraders in an enrichment culture and site groundwater. These tools could provide a basis for judging the potential of aerobic VC degradation by ethenotrophs at other sites in addition to offering a mechanism for treatment monitoring and system optimization. © 2009 Wiley Periodicals, Inc. 相似文献
267.
Importance of food quantity to structural growth rate and neutral lipid reserves accumulated in Calanus finmarchicus 总被引:1,自引:0,他引:1
Growth and developmental rates were determined for copepodids of Calanus finmarchicus (Gunnerus) from experimental seawater mesocosms in a western Norwegian fjord. The instantaneous growth rates (g) from copepodid stage I (CI) to adult ranged from 0.08 to 0.10 d−1. Daily per capita mortality rate of the cohorts was as low as 0.012 d−1 (1.2% d−1). At local increasing temperatures (5.1 to 8.3 °C), development was equiproportional, and the cumulative median development
time from egg to CV was approximately 65 d. CV moulted to males and females, and egg production was initiated. Enhancement
of food resources by nutrient addition caused a 23.4% increase in growth rates from CI to adult. Additionally, copepodid stages
showed a generally larger body size, carbon and nitrogen content and total storage lipid content (wax esters + triacylglycerols)
in response to enhanced resources. Our data support an elsewhere proposed exponential-growth hypothesis; growth of the structural
compartments and store lipids (mostly wax esters) was exponential during the copepodid stages. However, a sigmoidal pattern
of growth best described growth of adult stages if reared at high resources, and depot lipid accumulation in late CVs and
adults at high resources. Body nitrogen growth increased exponentially, however, no significant changes in nitrogen specific
growth rates were found between individuals from low and high resources. CV and adults seem to have reached near-maximal weights
at high resources, whereas structural weight continued to increase at low resources. Despite the differences in structural
growth dynamics, cohort development was similar until the end of CV. During the onset of sexual differentiation, the male:female
ratio and the adult:CV ratio were highest at high food resources, suggesting that the time used for the final moult depends
on the feeding history of the copepods in relation to food quality and quantity. It appears that relatively small changes
in food availability strongly influence the biochemical composition of C. finmarchicus copepodids.
Received: 28 May 1999 / Accepted: 10 February 2000 相似文献
268.
L G Hansen B M Francis R L Metcalf J H Reinders 《Journal of environmental science and health. Part. B》1985,20(1):97-111
Two allylthiocarbamate herbicides, diallate and triallate, were evaluated for neurotoxicity by oral and topical dosing studies with mature white leghorn hens. Diallate was tolerated for 90 days at topical doses of 40 mg/kg/day and oral doses of 20 mg/kg/day. Reversible ataxia and narcosis occurred at diallate doses of 80 mg/kg/day and higher by either route of administration. Triallate did not elicit signs of neurotoxicity at 300 mg/kg/day topically or 400 mg/kg/day orally. The oral dose, however, resulted in gastrointestinal irritation and severe weight loss, such that dosing was terminated after 25 days. Triallate was tolerated at oral dosages of 90 mg/kg/day and topical doses up to 330 mg/kg/day. 相似文献
269.
Photooxidation studies of 1,3-, 1,4-, 1,8- and 2,3-dimethylnaphthalene (DMN) suspended in and layered on seawater and distilled water have been performed in the presence and absence of crude Ekofisk oil, methylene blue and dibenzothiophene. With the exception of 2,3-DMN which was very insensitive to the reaction conditions, the course of reaction was, generally, influenced by the structure of the substrate, the salinity of the water, the oil and the presence of sulfur-containing compounds. In the absence of oil the photooxidation was fairly inefficient and took place exclusively in benzylic positions. In the presence of oil oxidation of the naphthalene moiety predominated due to abundant formation of singlet oxygen. 相似文献
270.
The sorption of the pyrethroid, esfenvalerate, to the dissolved and/or dispersed fraction of eight different natural humic compounds has been investigated. The dissolved organic matters (DOMs) included in this study originate from ground water, soil pore water, and surface waters. Sorption was modelled at DOM concentration levels where equilibrium partitioning of esfenvalerate between DOM and the aqueous bulk phase prevails. The inherent characteristics of the eight different humic materials, quantified in the preceding paper by Thomsen et al. (2002, this issue (PII: S0045-6535(02)00335-1)), have been used as explanatory variables for modelling this equilibrium partitioning. Using a reverse QSAR approach based on by projection-into-latent-structure regression (PLS-R) inherent sorbent properties determining for the sorption affinity of esfenvalerate to DOM were analysed. For all humic substances a decrease in the DOM-normalised equilibrium-partitioning coefficient, KDOM, with increasing concentration of DOM was observed. Significant variations in KDOM values, as function of the inherent characteristics of the individual humic substances, were found at DOM concentrations of 75 and 100 ppm, respectively. The latter is a strong indication of variations in sorption mechanisms of esfenvalerate to DOM of varying inherent properties. Groupings in the principal property space quantifying DOMs may indicate that separate models are needed for quantifying the equilibrium partitioning to different classes of DOM. 相似文献