全文获取类型
收费全文 | 375篇 |
免费 | 5篇 |
国内免费 | 12篇 |
专业分类
安全科学 | 23篇 |
废物处理 | 17篇 |
环保管理 | 27篇 |
综合类 | 72篇 |
基础理论 | 85篇 |
污染及防治 | 114篇 |
评价与监测 | 32篇 |
社会与环境 | 19篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 8篇 |
2017年 | 11篇 |
2016年 | 9篇 |
2015年 | 16篇 |
2014年 | 20篇 |
2013年 | 21篇 |
2012年 | 19篇 |
2011年 | 27篇 |
2010年 | 17篇 |
2009年 | 21篇 |
2008年 | 20篇 |
2007年 | 21篇 |
2006年 | 29篇 |
2005年 | 22篇 |
2004年 | 9篇 |
2003年 | 20篇 |
2002年 | 11篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 5篇 |
1998年 | 3篇 |
1997年 | 5篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1990年 | 2篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1956年 | 1篇 |
1954年 | 1篇 |
1950年 | 1篇 |
1941年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有392条查询结果,搜索用时 15 毫秒
131.
We report for the first time the use of beetroot fibers to eliminate heavy metals from polluted water. This biomass is used to remove lead, copper and zinc ions. The kinetics and beetroot fibers fixation capacities of lead, zinc and copper according to various physico‐chemical parameters such as pH, and the concentration of metal solutions were studied. The experiments were carried out in a laboratory column with fixed bed. For kinetic studies, samples of metal solutions were taken at regular intervals and measured by atomic absorption spectrometry. pH at 6.6 shows a maximum retention of the above cited metals by beetroot fibers (98%, 92%, 90% respectively). Quantity of cations retained by this biomass in simple and mixture solution is respectively estimated to be 23.6, 14.02 and 14.64 mg/g. Results indicate the usefulness of this biomass in the remediation of water contaminated by heavy metals by a rapid, practical and efficient method. 相似文献
132.
133.
The aim of this paper is to understand the temporal changes in planktonic populations and to highlight some important factors that control the biological functioning and evolution of a recently flooded reservoir, the Sep reservoir (Massif Central, France). To achieve this objective, a 1D vertical coupled physical–biological model was used and developed. It couples relevant physical processes (dispersion, advection and convection) with biological processes taking into account the complexity of interactions within the microbial food web, including the conventional grazing food chain with a microbial loop. 相似文献
134.
In populations of various ant species, many queens reproduce in the same nest (polygyny), and colony boundaries appear to
be absent with individuals able to move freely between nests (unicoloniality). Such societies depart strongly from a simple
family structure and pose a potential challenge to kin selection theory, because high queen number coupled with unrestricted
gene flow among nests should result in levels of relatedness among nestmates close to zero. This study investigated the breeding
system and genetic structure of a highly polygynous and largely unicolonial population of the wood ant Formica paralugubris. A microsatellite analysis revealed that nestmate workers, reproductive queens and reproductive males (the queens' mates)
are all equally related to each other, with relatedness estimates centring around 0.14. This suggests that most of the queens
and males reproducing in the study population had mated within or close to their natal nest, and that the queens did not disperse
far after mating. We developed a theoretical model to investigate how the breeding system affects the relatedness structure
of polygynous colonies. By combining the model and our empirical data, it was estimated that about 99.8% of the reproducing
queens and males originated from within the nest, or from a nearby nest. This high rate of local mating and the rarity of
long-distance dispersal maintain significant relatedness among nestmates, and contrast with the common view that unicoloniality
is coupled with unrestricted gene flow among nests.
Received: 8 February 1999 / Received in revised form: 15 June 1999 / Accepted: 19 June 1999 相似文献
135.
Conservative solute tracer experiments were conducted in Indian Creek, a small urban stream located in Philadelphia, Pennsylvania, USA. Estimated flow rates were between 46 Ls(-1) and 81 Ls(-1), average stream width was 5.5m and average stream depth was 0.2m. Given these dimensions, most researchers would think it reasonable to assume that the stream is completely mixed vertically and horizontally. However, we found that the stream was not vertically completely mixed in a 1.0m deep, 30 m long pool. The limited mixing was demonstrated by the vertical stratification of a tracer cloud which was completely mixed both laterally and vertically across the stream prior to entering the pool. We suggest that the cause of limited mixing is due to a balance between groundwater inflow and transverse dispersion at the cross-section. We show that the unsupported assumption of complete mixing may result in a wide range, and thus increased uncertainty, of the values of stream flow and longitudinal dispersion coefficient estimated from these data. We conclude that the assumption of complete mixing and one-dimensional modeling must be checked against actual field conditions, even in small streams. 相似文献
136.
Cui Fangda Zhao Lin Daskiran Cosan King Thomas Lee Kenneth Katz Joseph Boufadel Michel C. 《Environmental Fluid Mechanics》2020,20(6):1553-1578
Environmental Fluid Mechanics - Oil dispersion under a deep-water plunging breaker of height 0.15 m was studied by coupling the Lagrangian particle tracking code (NEMO3D) with the... 相似文献
137.
Kumpiene J Mench M Bes CM Fitts JP 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1536-1542
Field plots were established at a timber treatment site to evaluate remediation of Cu contaminated topsoils with aided phytostabilization. Soil containing 2600 mg kg−1 Cu was amended with a combination of 5 wt% compost and 2 wt% iron grit, and vegetated. Sequential extraction was combined with extended X-ray absorption fine structure (EXAFS) spectroscopy to correlate changes in Cu distribution across five fractions with changes in the predominant Cu compounds two years after treatment in parallel treated and untreated field plots. Exchangeable Cu dominated untreated soil, most likely as Cu(II) species non-specifically bound to natural organic matter. The EXAFS spectroscopic results are consistent with the sequential extraction results, which show a major shift in Cu distribution as a result of soil treatment to the fraction bound to poorly crystalline Fe oxyhydroxides forming binuclear inner-sphere complexes. 相似文献
138.
Anne-Catherine Bénard Vincent Darcos Christian Drakides Claude Casellas Jean Coudane Michel Vert 《Journal of Polymers and the Environment》2011,19(1):40-48
Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many end up in wastewater and,
later on, in wastewater-treatment plants. In order to gain an insight into their fate in such plants, fluorescence and radioactivity
labelings were compared using a lab-scale reactor designed to mimic industrial conditions. Two fermentation media were considered,
namely a mixture of E402 and E204 micro-organisms and an activated sludge collected from a water-treatment plant located in
the south of France. A sample of low molar mass commercial poly(acrylic acid) (PAA) was labeled by radioactivity with tritium
and by coupling the 6-aminofluorescein fluorescent dye. Labeled PAA-containing sludges were allowed to ferment. To monitor
the fate of the polymers, aliquots of the fermented mixtures were withdrawn at selected times and centrifuged. Liquid and
solid phases were analyzed by scintigraphy or UV spectrometry, depending of the labeling techniques. Both techniques led to
similar distributions, c.a. 75% in the supernatant and 25% in the solid phase. Distributions remained constant during the
biological tests. There was no degradation of the commercial PAA after aqueous size exclusion chromatography (SEC), in agreement
with literature. These features showed that fluorescence-labeling can be used instead of the complex and expensive radiolabeling.
The validated fluorescence-based method was then applied to a linear poly(acrylic acid) synthesized by ATRP and labeled with
6-aminofluorescein. There was no significant difference between the commercial and the linear poly(acrylic acid)s. In contrast,
a linear PAA with 5% of tert-butyl ester repeating units was predominantly found in the solid phase although adsorption or absorption by micro-organisms
could not be demonstrated. The method based on fluorescence labeling should be applicable to other water soluble polymers
provided that the dye remains attached to the polymer as it was the case for the studied poly(acrylic acid)s. 相似文献
139.
Michel P. Bonin William L. Flower Ronald F. Renzi Lawrence W. Peng 《Journal of the Air & Waste Management Association (1995)》2013,63(11):902-907
Abstract Optical measurements of particle size and concentration were made at the chromium plating tank and exhaust system at a commercial hexavalent chromium plating facility. Particles were examined at three locations in the exhaust system: 1) directly at the hexavalent chromium plating bath surface, 2) at the exit of a cyclone separator located in the exhaust system approximately three to four meters downstream of the bath, and 3) in the exhaust stack, downstream of the induced draft fan and all abatement devices. Particle diameters at the bath surface ranged from 0.3 to 25 μm. Downstream of the cyclone exit and mesh pad filters, particle top sizes were approximately 5 and 0.7 mm, respectively. On a mass basis, the collection efficiency of all abatement devices was 99.997%. Assuming that droplets in the flow consist primarily of water and chromium, correcting the total particle mass flow against water content gives a chromium emission rate of 64,000 μg/hr, which compares favorably with a value of 77,000 μg/hr measured with EPA methods. This initial agreement, which should be validated through additional measurements over a broad range of flow conditions, raises the possibility of continuous monitoring for chromium metal emissions using particle size/mass as a surrogate. 相似文献
140.
Sophie Gauthier-Clerc Isabelle Boily Michel Fournier Karine Lemarchand 《Environmental science and pollution research international》2013,20(2):612-620
Mussels are widespread in coastal environments and experience various physical, chemical, and bacteriological conditions. Owing to the increase of coastal urbanization, mussels are now commonly exposed not only to indigenous bacteria, but also to enteric bacteria originating from pulsed and chronic sewage discharges into coastal environments. Due to its broad resilience to environmental variations, the blue mussel Mytilus edulis is commonly used as an indicator of environmental quality in bio-monitoring programs. However, since mussel immune system capabilities may be affected by the presence of exogenous fecal bacteria in coastal seawater subjected to sewage discharges, we aimed to determine the effect of in vivo bacterial challenges on mussels' immune competency by using two exogenous enteric bacterial strains, Escherichia coli and Enterococcus faecalis, and an indigenous bacterial strain Vibrio splendidus (as control). Bacterial strains were tested individually, by injection into the posterior adductor muscle at three different cell densities (102, 103, and 104 cells). Unlike classic in vitro experiments using higher bacterial concentrations, neither the enteric bacteria nor the indigenous strain induced significant increase or decrease of either cell-mediated (phagocytosis, reactive oxygen species, and NO x production) or humoral components (prophenoloxidase-like, acid phosphatase, and l-leucine-aminopeptidase production) of the immune system. This study demonstrates that, at low concentrations, E. coli and E. faecalis do not represent an additional threat that could impair M. edulis immune competency and, as a consequence, its potential of survival in coastal areas subjected to sewage discharges. 相似文献