全文获取类型
收费全文 | 743篇 |
免费 | 4篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 24篇 |
废物处理 | 40篇 |
环保管理 | 84篇 |
综合类 | 135篇 |
基础理论 | 105篇 |
污染及防治 | 258篇 |
评价与监测 | 65篇 |
社会与环境 | 42篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 10篇 |
2022年 | 24篇 |
2021年 | 18篇 |
2020年 | 15篇 |
2019年 | 8篇 |
2018年 | 21篇 |
2017年 | 24篇 |
2016年 | 34篇 |
2015年 | 25篇 |
2014年 | 44篇 |
2013年 | 79篇 |
2012年 | 52篇 |
2011年 | 59篇 |
2010年 | 31篇 |
2009年 | 37篇 |
2008年 | 53篇 |
2007年 | 34篇 |
2006年 | 39篇 |
2005年 | 38篇 |
2004年 | 20篇 |
2003年 | 24篇 |
2002年 | 15篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1986年 | 2篇 |
1982年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有756条查询结果,搜索用时 31 毫秒
101.
Monte L Periañez R Kivva S Laptev G Angeli G Barros H Zheleznyak M 《Journal of environmental radioactivity》2006,88(3):267-288
The performances of models are assessed to predict the wash-off of radionuclides from contaminated flooded areas. This process should be accounted for in the proper management of the aftermath of a nuclear accident. The contamination of the Pripyat River water following the inundation of a floodplain heavily contaminated by (90)Sr and (137)Cs of Chernobyl origin is used as the basis for modelling. The available experimental evidence demonstrated that remobilisation of radiostrontium is an important process implying a significant secondary radioactive load of water flowing over the contaminated floodplain. On the contrary, there is no empirical evidence of a similar behaviour for radiocaesium. In general, state-of-the-art models properly predicted the remobilisation of strontium, whereas they significantly overestimated radiocaesium concentrations in water. The necessary model improvements for a more accurate prediction of radiocaesium contamination levels include a reassessment of the values of the model parameters controlling the remobilisation process. 相似文献
102.
Christian Diaz-Ovalle Richart Vazquez-Roman Raul Lesso-Arroyo M. Sam Mannan 《Journal of Loss Prevention in the Process Industries》2012,25(6):974-981
Curtain mitigation systems are modeled here since they have experimentally shown their efficiency in reducing the concentration of certain toxic gases within dense gas clouds. Air, water and steam are analyzed in a model as the physical barriers to decrease the gas concentration. The model, developed for a steady-state mitigation process, is based on the mass, energy and momentum conservation laws. Concentration estimations during the dispersion before and after the mitigation are performed with a SLAB type model. A sensitivity analysis for each model is given to detect which variables have bigger effects. A release of chlorine is used as an example and the results are calculated in a prototype developed in Visual C++, where the model is solved using the Runge–Kutta 4th order method. The results include the effects of composition, speed, temperature and height of the releasing point as well as a comparison with CFD simulations. The proposed model is simplified and it cannot reproduce eddy effects but it is fast and robust enough. The model provides a set of equations that can be used in numerical problems where explicit derivatives are required, e.g. optimizations procedures. 相似文献
103.
Zhu Jun Fu Qingling Qiu Guohong Liu Yurong Hu Hongqing Huang Qiaoyun Violante Antonio 《Environmental Chemistry Letters》2019,17(3):1271-1280
Environmental Chemistry Letters - The sorption of heavy metals by soil constituents reduces the absorption of these pollutants by crops and vegetables, and thus limit food contamination. Low... 相似文献
104.
Tominaga Flávio Kiyoshi Silva Thalita Tieko Boiani Nathalia Fonseca de Jesus Juliana Mendonça Silva Teixeira Antonio Carlos Silva Costa Borrely Sueli Ivone 《Environmental science and pollution research international》2021,28(19):23975-23983
Environmental Science and Pollution Research - Wastewater and effluent discharges are the main causes of receiving water body pollution and important challenges in water quality management. Among... 相似文献
105.
106.
Ninon F. V. Meyer Ricardo Moreno Christopher Sutherland J. Antonio de la Torre Helen J. Esser Christopher A. Jordan Melva Olmos Josué Ortega Rafael Reyna-Hurtado Samuel Valdes Patrick A. Jansen 《Conservation biology》2020,34(1):207-219
Habitat fragmentation is a primary driver of wildlife loss, and establishment of biological corridors is a common strategy to mitigate this problem. A flagship example is the Mesoamerican Biological Corridor (MBC), which aims to connect protected forest areas between Mexico and Panama to allow dispersal and gene flow of forest organisms. Because forests across Central America have continued to degrade, the functioning of the MBC has been questioned, but reliable estimates of species occurrence were unavailable. Large mammals are suitable indicators of forest functioning, so we assessed their conservation status across the Isthmus of Panama, the narrowest section of the MBC. We used large-scale camera-trap surveys and hierarchical multispecies occupancy models in a Bayesian framework to estimate the occupancy of 9 medium to large mammals and developed an occupancy-weighted connectivity metric to evaluate species-specific functional connectivity. White-lipped peccary (Tayassu pecari), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), white-tailed deer (Odocoileus virginianus), and tapir (Tapirus bairdii) had low expected occupancy along the MBC in Panama. Puma (Puma concolor), red brocket deer (Mazama temama), ocelot (Leopardus pardalis), and collared peccary (Pecari tajacu), which are more adaptable, had higher occupancy, even in areas with low forest cover near infrastructure. However, the majority of species were subject to ≥1 gap that was larger than their known dispersal distances, suggesting poor connectivity along the MBC in Panama. Based on our results, forests in Darien, Donoso–Santa Fe, and La Amistad International Park are critical for survival of large terrestrial mammals in Panama and 2 areas need restoration. 相似文献
107.
Ernesto Azzurro Antonio Pais Pierpaolo Consoli Franco Andaloro 《Marine Biology》2007,151(6):2245-2253
Ecological information on coastal fish distribution patterns and habitat use can be greatly improved by nocturnal samplings
and observations. To this purpose, the structure of a Mediterranean fish assemblage inhabiting the shallow rocky littoral
of Linosa Island (Sicily Strait, Italy) was examined by using visual census to detect possible diel variations in species
composition and abundance. Day–night fish distribution patterns were investigated by multivariate and univariate analyses.
Overall, 42 fish taxa belonging to 19 families were recorded: 35 during the day and 24 during the night. Seventeen species
were common to both diurnal and nocturnal assemblages. Within the diurnal assemblage, Chromis chromis was the most represented species (37.2%), followed by Thalassoma pavo (23.2%) and Sparisoma cretense (10.8%). Within the nocturnal assemblage, the most abundant taxon was Atherina spp. (33.9%), followed by Apogon imberbis (26.4%) and Boops boops (11.5%). Our results indicated wide variation in the abundance and species composition during the day and during the night.
Multi Dimensional Scaling plot showed a clear-cut separation between the two assemblages and analysis of similarities found
significant differences as well. SIMPER analysis revealed that ten species individually contributed by more than 2.5% to the
dissimilarity between diurnal and nocturnal assemblages, T. pavo, C. chromis and S. cretense being the first three species in order of decreasing percentage. ANOVA performed on species richness and fish abundance detected
significant differences between diurnal and nocturnal assemblages, the latter showing far lower average values for both variables. 相似文献
108.
Natural History: Hobby or Science? 总被引:1,自引:0,他引:1
Jesús Antonio Rivas 《Conservation biology》1997,11(3):811-812
109.
Antonio Brante 《Marine Biology》2006,149(2):269-274
Oxygen supply inside egg masses has been reported as a constraint of embryo development. Many species that enclose their eggs in jelly masses or ovicapsules have strategies to avoid or reduce intracapsular hypoxia. In some amphibian species, a decrease in the wall thickness of the egg capsule over time produces an increase in oxygen conductance of the wall, reducing the problem of intracapsular oxygen limitation. Previous studies of gastropods have reported a decrease in the thickness of the capsules during development. However, there are no studies relating capsule thinning to the oxygen limitation problem in this group. This study links the thinning of egg capsules with oxygen diffusion as a possible mechanism to reduce or avoid hypoxia inside the capsules of the gastropod Fusitriton oregonensis. Capsule thickness, capsule area, oxygen partial pressure inside and outside the capsule, and oxygen consumption of the embryos at early and late developmental stages were measured. The conductance and the diffusion coefficients of the capsule were estimated using these measurements. Results showed that (1) capsule thickness decreased throughout development by about 50%, (2) oxygen consumption of embryos increased from early to late stages, (3) oxygen partial pressure inside the capsule did not change during development, (4) conductance coefficient increased with time, and (5) estimation of diffusion coefficient was lower than amphibian egg jelly, shark capsules, egg fishes, and eggs of giant cuttlefish. The reduction in the thickness of the capsule wall and the associated increase in its conductance during embryonic development may reduce oxygen constraints, especially at late developmental stages. 相似文献
110.
Antonio J. Palazzo 《Environmental geochemistry and health》1994,16(1):3-7
Frequently, turfgrass seedings have been sown in the late fall, which usually results in a poor vegetative stand and the possibility of soil erosion the following spring. This study evaluates the effects of a spun-bonded polyester soil cover placed over a late-fall seeding on subsequent seedling growth and overwintering. Clemfine, Mustang, Rebel, and Rebel II cultivars of tall fescue (Festuca arundinacea Schreb.) were sown on a silt loam soil in late fall (on 17 October in 1989 and 19 October in 1990) and allowed to grow with and without a soil cover until June. In the spring the temperature under the soil cover was greater than 2°C warmer than the uncovered soil from mid-April through May. Over the winter, leaf and root weights showed no detrimental effects from being under the cover. Individual cultivars grown under the cover produced 2 to 11 times greater leaf yields and 38 to 270% better stand establishment than those sown on the exposed soil. However, plant winter injury was observed under the soil cover in small soil depressions which accumulated water originating from thawing. All cultivars had similar amounts of growth under the cover. However, leaf yields for Rebel were 30-55% less than the other cultivars when grown under the cover and this was probably related to a low seed germination rate. The covers also promoted weed growth, which comprised from 34–65% of total leaf weights and was found to be negatively correlated (r = –0.66) to the yields of the sown grass. The soil cover was found to be beneficial to improving the success of seedling establishment of late seedings of tall fescue in cold areas. 相似文献