全文获取类型
收费全文 | 366篇 |
免费 | 1篇 |
国内免费 | 8篇 |
专业分类
安全科学 | 7篇 |
废物处理 | 12篇 |
环保管理 | 29篇 |
综合类 | 105篇 |
基础理论 | 67篇 |
环境理论 | 1篇 |
污染及防治 | 106篇 |
评价与监测 | 26篇 |
社会与环境 | 19篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 7篇 |
2022年 | 4篇 |
2021年 | 18篇 |
2020年 | 10篇 |
2019年 | 6篇 |
2018年 | 17篇 |
2017年 | 17篇 |
2016年 | 18篇 |
2015年 | 13篇 |
2014年 | 17篇 |
2013年 | 29篇 |
2012年 | 26篇 |
2011年 | 28篇 |
2010年 | 10篇 |
2009年 | 18篇 |
2008年 | 16篇 |
2007年 | 26篇 |
2006年 | 22篇 |
2005年 | 9篇 |
2004年 | 15篇 |
2003年 | 13篇 |
2002年 | 3篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1979年 | 1篇 |
1975年 | 1篇 |
1967年 | 1篇 |
1962年 | 1篇 |
1961年 | 2篇 |
1957年 | 2篇 |
1956年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有375条查询结果,搜索用时 156 毫秒
341.
Lars T. Waser Meinrad Kuechler Markus Schwarz Eva Ivits Silvia Stofer Christoph Scheidegger 《Environmental Modeling and Assessment》2007,12(4):315-328
The present study focuses on developing models to predict lichen species richness in a UNESCO Biosphere Reserve of the Swiss
Pre-Alps following a gradient of land-use intensity combining remote sensing data and regression models. The predictive power
of the models and the obtained r ranging from 0.5 for lichens on soil to 0.8 for lichens on trees can be regarded as satisfactory to good, respectively. The
study revealed that a combination of airborne and spaceborne remote sensing data produced a variety of ecological meaningful
variables. 相似文献
342.
Thöni L Brang P Braun S Seitler E Rihm B 《Environmental monitoring and assessment》2004,98(1-3):93-107
Gaseous ammonia (NH3) is an important form of N deposition to ecosystems, but it is not being routinely monitored in Switzerland. Therefore, a study was conducted to estimate annual means and seasonal patterns of NH3 concentrations for different site types in Switzerland, and to compare annual measured and modelled NH3 concentrations. NH3 concentrations were measured using the 'Zürcher' passive sampler, a Palmes type sampler with an acidic solution as absorbent. Twenty-four sampling sites were run for one year, and 17 for two years. The samplers were changed fortnightly or monthly. Spatial emission patterns were mapped by combining information on (1) the location of emission sources, (2) national statistics on NH3-emitting activities and (3) activity-specific emission factors. The spatial resolution was one hectare. The mean annual NH3 concentration in the ambient air of the 41 sites was 2.5+/-0.3 microg m(-3) (mean+/-standard error). It ranged from 0.4 to 7.5 microg m(-3). The site type and the season were the most important factors explaining the variation in the seasonal mean concentration. NH3 concentrations were highest in intensively used agricultural areas and in cities, and lowest in Alpine sites remote from emission sources. At 39 out of 41 sites, the NH3 concentrations were higher in summer (3.1+/-0.3 microg m(-3)) than in winter (2.0+/-0.3 microg m(-3)). Modelled NH3 concentrations did not systematically deviate from measured concentrations (r2 = 0.69). With the combined monitoring and modelling approach, it is now possible to obtain a reasonable and consolidated picture of the overall NH3 situation in Switzerland. 相似文献
343.
Katarina Tokarova Jaromir Vasicek Rastislav Jurcik Andrej Balazi Eva Kovacikova 《Journal of environmental science and health. Part. B》2019,54(6):459-466
In the present study, we aimed to assess antioxidant status in erythrocytes in vitro after patulin (PAT) and epicatechin exposure by measuring antioxidant enzymes (superoxide-dismutase – SOD, glutathione peroxidase – GPx and catalase – CAT) and parameters associated with oxidative stress (malondialdehyde – MDA and ROS). We also investigated the effect of PAT on viability and count of lymphocytes and lymphocyte subpopulations in rabbit blood in vitro. Whole blood of rabbits was used for analysis of antioxidant changes in rabbit erythrocytes after epicatechin and PAT treatment (separately or in combination, at concentrations of 0.2; 2; 20; 200?µg mL–1 of epicatechin and 0.5; 5; 10?µg mL–1 of PAT). Whole blood of rabbits was also used for analysis of count and viability of lymphocytes after PAT treatment at concentrations of 10; 25 and 50?µg mL–1. Results from our experiment confirmed the ability of epicatechin to protect cells against oxidative stress and lipoperoxidation. Our findings indicate that mycotoxin PAT in low concentrations did not affect the activity of antioxidant enzymes in erythrocytes of rabbits significantly. Only slight non-significant changes in lymphocytes count after treatment with low doses of PAT in rabbit blood were observed. 相似文献
344.
Pekárek V Karban J Fiserová E Bures M Pacáková V Vecerníková E 《Environmental science and pollution research international》2003,10(1):39-43
BACKGROUND, AIMS AND SCOPE: It is well known that the fly ash from filters of municipal waste incinerators (MWI-FA) shows dehalogenation properties after heating it to 240-450 degrees C. However, this property is not general, and fly ash samples do not possess dehalogenation ability at all in many cases. Fly ash has a very variable composition, and the state of the fly ash matter therefore plays the decisive role. In the present paper, the function of important components responsible for the dehalogenation activity of MWI-FA is analysed and compared with the model fly ash. METHODS: With the aim of accounting for the dehalogenation activity of MWI-FA, the following studies of hexachlorobenzene (HCB) dechlorination were performed: The role of copper in dehalogenation experiments was evaluated for five types of metallic copper. The gasification of carbon in MWI-FA was studied in the 250-350 degrees C temperature range. Five different kinds of carbon were used, combined with conventional Cu(o) and activated nanosize copper powder. The dechlorination experiments were also carried out with Cu(II) compounds such as CuO, Cu(OH)2, CuCl2 and CuSO4. The results were discussed from the standpoint of thermodynamics of potential reactions. Based on these results, the model of fly ash was proposed, containing silica gel, metallic copper and carbon. The dechlorination ability of MWI-FA and the model fly ash are compared under oxygen-deficient atmosphere. CONCLUSIONS: The results show that, under given experimental conditions, copper acts in the dechlorination as a stoichiometric agent rather than as a catalyst. The increased surface activity of copper enhances its dechlorination activity. It was found further that the presence of copper leads to a decrease in the temperature of carbon gasification. The cyclic valence change from Cu(o) to Cu+ or Cu2+ is a prerequisite for the dehalogenation to take place. RECOMMENDATION AND OUTLOOK: Thermodynamic analysis of the dechlorination effect, as well as the comparison of dechlorination pathways on MWI-FA and model fly ash, can provide a deeper understanding of the studied reaction. 相似文献
345.
This article contributes to the debate on the role of local sustainability indicators in ongoing democratisation efforts. We examine the extent to which five different systems of local sustainability indicators within two Swedish municipalities—Stockholm and Sundsvall—are either expert or citizen oriented, and relate these findings to the indicator systems' profile, function and political/ administrative context. Even though three of the indicator systems can be classified as citizen oriented, there are few signs of true engagement and dialogue with the citizens over a longer period of time. The remaining two indicator systems are expert oriented with an environmental focus. Hence, we conclude that the systems in use are largely symbolic responses to the demands for democracy within the agenda for sustainable development albeit attempts to include environmental, economic, social and democratic perspectives of sustainability. Despite the fact that Stockholm and Sundsvall show differences in governing styles in their approaches to sustainability indicators it seems difficult for both municipalities to put sustainable development into practice in terms of citizen participation. 相似文献
346.
Ingolf Schuphan Sabine Maier-Gaipl Eva Herlitz Jutta Schreiner Ursula Tietz 《Environmental Sciences Europe》1997,9(1):7-11
Initial values and windows of competence together with a biological test system are introduced to identify soil contaminations. Theinitial values are defined as the amount of extract equivalent to a defined amount of soil (gramm soil equivalent) and the same amount of test medium. This is equivalent to a complete replacement of the test medium with the soil being tested. Theeffect limits should be at least the double standard deviation of the blank values. Based on the values found when testing uncontaminated soils, a higher threshold value has to be established for some test systems. Should no relationship be found to a standard test medium (e.g. agar as a matrix in the Ames assay), the so-calledwindow of competence is defined. Within this window no natural response is found when ex amining uncontaminated soil. For mutagenicity tests, the double spontaneous reversion rate (reversion coefficient of 2) as related o the blank sample is evaluated as the effect limit. 相似文献
347.
Summary. By means of gas chromatography, gas
chromatographic coupled mass spectrometry and behavioral
analysis the major trail pheromone components from the
hindgut of the formicine species Camponotus castaneus, C.
balzani and C. sericeiventris were identified. The trail
pheromone of C. castaneus is 3,5-dimethyl-6-(1-methylpropyl)-
tetrahydro-2H-pyran- 2-one, and that of the other
two species is 3,4-dihydro-8-hydroxy-3,5,7-trimethylisocoumarin.
Although both compounds release precise trail
following behavior in the respective species, the major
recruitment signal in the three Camponotus species appears
to be formic acid discharged from the poison gland. The
composition of the Dufour gland secretions of C. castaneus
and C. sericeiventris is similar, but that of the hypertrophied
Dufour gland of C. balzani is very different from any other
Camponotus Dufour gland content described up to date: it
contains large amounts of esters, the major compound of
which is octyl hexanoate, which makes up 97% a/a of the
total volatiles. 相似文献
348.
Bart Wouters Marijn Nijssen Gertjan Geerling Hein Van Kleef Eva Remke Wilco Verberk 《Journal of Coastal Conservation》2012,16(1):89-99
Encroachment of tall grasses and shrubs in coastal dunes has resulted in loss of vegetation heterogeneity. This is expected
to have negative effects on animal diversity. To counteract encroachment and develop structural heterogeneity grazing is a
widely used management practice. Here, we aim to functionally interpret changes in vegetation composition and configuration
following grazing management on habitat suitability for sand lizards. Aerial photographs taken over a period of 16 years were
used to quantify changes in vegetation composition. A GIS-based method was developed to calculate habitat suitability for
sand lizards in a spatially explicit manner, encompassing differences in vegetation structure and patch size. From 1987 to
2003 dune vegetation shifted from small patches of moss and sand to larger patches covered by shrubs and grasses. Grazing
management did not have any significant effect on the overall level of heterogeneity, measured as habitat suitability for
sand lizards. However, on a more local scale highly suitable patches in 1987 were deteriorating whereas unsuitable patches
became more suitable in 2003. This inversion results from a broad shift with shrubs being a limiting habitat element in 1987
to sandy patches being the limiting element in 2003. Future changes are believed to negatively impact sand lizards. The habitat
suitability model has proven to be a useful tool to functionally interpret changes in coastal dune vegetation heterogeneity
from an animal’s perspective. Further research should aim to include multiple species operating on different scale levels
to fully capture the natural landscape dynamics. 相似文献
349.
350.