全文获取类型
收费全文 | 105篇 |
免费 | 3篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 6篇 |
环保管理 | 11篇 |
综合类 | 20篇 |
基础理论 | 29篇 |
污染及防治 | 23篇 |
评价与监测 | 5篇 |
社会与环境 | 3篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 4篇 |
2011年 | 8篇 |
2010年 | 8篇 |
2009年 | 7篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 8篇 |
2005年 | 4篇 |
2004年 | 4篇 |
2002年 | 2篇 |
2001年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1989年 | 2篇 |
排序方式: 共有108条查询结果,搜索用时 31 毫秒
51.
Pauline Coster Mouloud Benammi Vincent Lazzari Guillaume Billet Thomas Martin Mustafa Salem Awad Abolhassan Bilal Yaowalak Chaimanee Mathieu Schuster Xavier Valentin Michel Brunet Jean-Jacques Jaeger 《Die Naturwissenschaften》2010,97(8):697-706
A new African species of hystricognathous rodent, Gaudeamus lavocati sp. nov., is described herein from the early Oligocene deposits of Zallah locality (Sirt basin, Central Libya). The dental morphology of this species is very close to that of some earliest South American caviomorphs. It allows a reinterpretation of molar crest homologies among earliest caviomorphs, pentalophodonty being confirmed as the plesiomorphic molar condition in Caviomorpha. This morphological resemblance argues for close affinities between Gaudeamus and earliest South American hystricognaths. Cladistic analysis supports Gaudeamus lavocati sp. nov. as the first known African representative of Caviomorpha, implying that its ancestors were part of the African phiomyid group that crossed the South Atlantic by a direct immigration route. Alternatively, the series of derived dental features of Gaudeamus could also be interpreted as evolutionary synchronous convergences of an African hystricognath lineage towards the specialized pattern of some caviomorphs. However, the high level of similarities concerning teeth morphology and enamel microstructure and the similar age of fossiliferous strata on both continents make this interpretation less probable. The phylogenetic position of this taxon is of considerable importance because it represents an enigmatic component of the phiomorph–caviomorph radiation in Africa and appears as a new clue toward the understanding of caviomorph origins. 相似文献
52.
Toan Nguyen Solveig Heide Lucie Guilbaud Stéphanie Valence Saskia Vande Perre Eléonore Blondiaux Boris Keren Geneviève Quenum-Miraillet Jean-Marie Jouannic Laurent Mandelbrot Olivier Picone Agnès Guet Vassilis Tsatsaris Mathieu Milh Nadine Girard Marie Vincent Mathilde Nizon Céline Poirsier Alexandre Vivanti Alexandra Benachi Vincent des Portes Laurent Guibaud Olivier Patat Myrtille Spentchian Lisa Frugère Delphine Héron Catherine Garel 《黑龙江环境通报》2023,43(6):746-755
53.
Balakrishnan VK Monteil-Rivera F Gautier MA Hawari J 《Journal of environmental quality》2004,33(4):1362-1368
The polycyclic nitramine CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is being considered for use as a munition, but its environmental fate and impact are unknown. The present study consisted of two main elements. First, sorption-desorption data were measured with soils and minerals to evaluate the respective contributions of organic matter and minerals to CL-20 immobilization. Second, since CL-20 hydrolyzes at a pH of >7, the effect of sorption on CL-20 degradation was examined in alkaline soils. Sorption-desorption isotherms measured using five slightly acidic soils (5.1 < pH < 6.9) containing various amounts of total organic carbon (TOC) revealed a nonlinear sorption that increased with TOC [K(d) (0.33% TOC) = 2.4 L kg(-1); K(d) (20% TOC) = 311 L kg(-1)]. Sorption to minerals (Fe(2)O(3), silica, kaolinite, montmorillonite, illite) was very low (0 < K(d) < 0.6 L kg(-1)), suggesting that mineral phases do not contribute significantly to CL-20 sorption. Degradation of CL-20 in sterile soils having different pH values increased as follows: sandy agricultural topsoil from Varennes, QC, Canada (VT) (pH = 5.6; K(d) = 15 L kg(-1); 8% loss) < clay soil from St. Sulpice, QC, Canada (CSS) (pH = 8.1; K(d) = 1 L kg(-1); 82% loss) < sandy soil provided by Agriculture Canada (SAC) (pH = 8.1, K(d) = approximately 0 L kg(-1); 100% loss). The faster degradation in SAC soil compared with CSS soil was attributed to the absence of sorption in the former. In summary, CL-20 is highly immobilized by soils rich in organic matter. Although sorption retards abiotic degradation, CL-20 still decomposes in soils where pH is >7.5, suggesting that it will not persist in even slightly alkaline soils. 相似文献
54.
Mathieu Giraudeau Camille Duval Noel Guillon Vincent Bretagnolle Claude Gutierrez Philipp Heeb 《Die Naturwissenschaften》2010,97(6):577-581
Preen glands exist in almost every bird species and several non-exclusive functions have been proposed for this gland and
the oils that it produces. One function generally admitted is that the oily secretions of the preen gland would provide a
waterproofing layer when spread over feathers. Alternatively, several authors have proposed that plumage waterproofness is
mostly due to the spatial micro-structure of feathers. The purpose of this study was to examine, by manipulating the access
to the preen gland, the effect of the preen oil on the plumage waterproofness and condition. To explore this question, we
carried out two independent experiments where we temporarily blocked access to the preen gland secretions with a removable
mechanism in one group of captive mallards (Anas platyrhynchos), whilst a second group of birds had access to gland secretions. In a long-term experiment (3 months of treatment) and a
short-term experiment (10 days), we measured plumage water retention and condition. After 3 months without access to preen
glands, we found a significant decrease of plumage condition and an associated increase in plumage water retention. Moreover,
we found a significant correlation between plumage condition and water retention ability. In contrast, after 10 days of treatment,
no significant effect was found on plumage condition and water retention. Our study shows that preen oil acts to maintain
plumage condition and suggests that feather microstructure is essential to maintain plumage waterproofness. 相似文献
55.
56.
Mark Thompson Jan Vlok Mathieu Rouget M. T. Hoffman Andrew Balmford R. M. Cowling 《Environmental management》2009,43(4):585-596
Improved techniques for measuring and monitoring the state of biodiversity are required for reporting on national obligations
to international and regional conservation institutions. Measuring the extent of grazing-related degradation in semi-arid
ecosystems has proved difficult. Here we present an accurate and cost-effective method for doing this, and apply it in a South
African semi-arid region that forms part of a globally significant biodiversity hotspot. We grouped structurally and functionally
similar vegetation units, which were expert-mapped at the 1:50,000 scale, into four habitat types, and developed habitat-specific
degradation models. We quantified degradation into three categories, using differences between dry and wet season values of
the Normalized Difference Vegetation Index (NDVI) for the three succulent karoo habitats, and the difference between maximum
and mean NDVI values for the subtropical thicket habitat. Field evaluation revealed an accuracy of 86%. Overall, degradation
was high: 24% of the study area was modeled as severely degraded, and only 9% as intact. Levels of degradation were highest
for bottomland habitats that were most exposed to grazing impacts. In sharp contrast to our methods, a widely used, broad-scale
and snapshot assessment of land cover in South Africa was only 33% accurate, and it considerably underestimated the extent
of severely degraded habitat in the study area. While our approach requires a multidisciplinary team, and in particular expert
knowledge on the characteristics and spatial delimitation of vegetation types, it is repeatable, rapid, and relatively inexpensive.
Consequently, it holds great promise for monitoring and evaluation programs in semi-arid ecosystems, in Africa, and beyond. 相似文献
57.
Model reduction via principal component truncation for the optimal design of atmospheric monitoring networks 总被引:1,自引:0,他引:1
Olivier Saunier Marc Bocquet Anne Mathieu Olivier Isnard 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):4940-4950
A numerically efficient methodology for the optimal design of monitoring networks aiming at the surveillance of accidental atmospheric release is proposed in this paper. In a realistic context, the design of such a network requires the knowledge of a database of potential dispersion accidents occurring in the domain of the study. An objective function measures the ability of a potential network to provide measurements in order to reconstruct any accidental plume taken from the database. In the optimisation of such cost functions with respect to networks, most of the computational time is spent in the evaluation of the function, especially if the accidents database is large. In this paper we show how to optimally reduce this database and how this affects the design via a mathematical expansion in the cost function. We introduce methods based on principal component analysis, which are rigorous when the cost function is of least-squares type. These methods are then tested and validated with success on the design of a radionuclides monitoring network to be deployed over France. This is the so-called Descartes network which will be operated by the French Institute for Radiation and Nuclear Safety. These techniques are then applied on Descartes to solve several issues that are computationally demanding, but are also of more general interest, such as: how should one sequentially deploy the stations of the network? How is affected the optimal network when other European potential radiological sources are taken into account? 相似文献
58.
Sabine Douxchamps Mark T. Van Wijk Silvia Silvestri Abdoulaye S. Moussa Carlos Quiros Ndèye Yacine B. Ndour Saaka Buah Léopold Somé Mario Herrero Patricia Kristjanson Mathieu Ouedraogo Philip K. Thornton Piet Van Asten Robert Zougmoré Mariana C. Rufino 《Regional Environmental Change》2016,16(5):1305-1317
Adaptation strategies to reduce smallholder farmers’ vulnerability to climate variability and seasonality are needed given the frequency of extreme weather events predicted to increase during the next decades in sub-Saharan Africa, particularly in West Africa. We explored the linkages between selected agricultural adaptation strategies (crop diversity, soil and water conservation, trees on farm, small ruminants, improved crop varieties, fertilizers), food security, farm household characteristics and farm productivity in three contrasting agro-ecological sites in West Africa (Burkina Faso, Ghana and Senegal). Differences in land area per capita and land productivity largely explained the variation in food security across sites. Based on land size and market orientation, four household types were distinguished (subsistence, diversified, extensive, intensified), with contrasting levels of food security and agricultural adaptation strategies. Income increased steadily with land size, and both income and land productivity increased with degree of market orientation. The adoption of agricultural adaptation strategies was widespread, although the intensity of practice varied across household types. Adaptation strategies improve the food security status of some households, but not all. Some strategies had a significant positive impact on land productivity, while others reduced vulnerability resulting in a more stable cash flow throughout the year. Our results show that for different household types, different adaptation strategies may be ‘climate-smart’. The typology developed in this study gives a good entry point to analyse which practices should be targeted to which type of smallholder farmers, and quantifies the effect of adaptation options on household food security. Subsequently, it will be crucial to empower farmers to access, test and modify these adaptation options, if they were to achieve higher levels of food security. 相似文献
59.
Marc Crampon Yoann Copard Guillaume Favreau Julie Raux Nadine Merlet-Machour Mathieu Le Coz Maïmouna Ibrahim Valérie Peulon-Agasse Florence Portet-Koltalo 《Environmental science and pollution research international》2014,21(18):10601-10613
Increased use of agrochemical products to improve yields for irrigated crops in sub-Saharan Africa has been accompanied by a significant increase in the risk of environmental contamination. Detailed examples of the fate of pesticides after initial spreading on crop fields are scarce in tropical regions, where safe practices and related health risks are poorly understood by smallholder farmers. In the semi-arid environment of the Lake Chad Basin, SE Niger, both intrinsic properties of pesticides and extrinsic factors such as soil and climate helped to characterize processes leading to an accumulation of pesticides in soils. Analysis by HPLC-UV of a 6 m deep soil profile showed the presence of Paraquat at concentrations from 953?±?102 μg kg?1 to 3083?±?175 μg kg?1 at depths between 0.80 and 2.75 m below the land surface. Soil analysis revealed that up to approximately 15 % of the total soil matrix consists of smectites, a clay mineral capable of retaining cationic pesticides such as Paraquat, and a very low content of organic matter (<0.15 wt.% TOC). Paraquat could be stored and not bioavailable in a clayey barrier at approximately 2-m depth and therefore does not represent an immediate risk for populations or environment in this form. However, if the Paraquat application rate remains constant, the clayey barrier could reach a saturation limit within 150–200 years and 180–220 years if we consider a DT50 in soil of ~1,000 days (FAO). Consequently, it could lead to a deeper infiltration and so a pollution of groundwater. Such a scenario can represent a health risk for drinking water and for the Lake Chad, which is a major resource for this densely populated region of semi-arid Africa. Further analyses should focus on deeper layers and groundwater Paraquat contents to validate or invalidate the hypothesis of storage in this clay-rich layer. 相似文献
60.
Deloge-Abarkan M Ha TL Robine E Zmirou-Navier D Mathieu L 《Journal of environmental monitoring : JEM》2007,9(1):91-97
Aerosols of water contaminated with Legionella bacteria constitute the only mode of exposure for humans. However, the prevention strategy against this pathogenic bacteria risk is managed through the survey of water contamination. No relationship linked the Legionella bacteria water concentration and their airborne abundance. Therefore, new approaches in the field of the metrological aspects of Legionella bioaerosols are required. This study was aimed at testing the main principles for bioaerosol collection (solid impaction, liquid impingement and filtration) and the in situ hybridization (FISH) method, both in laboratory and field assays, with the intention of applying such methodologies for airborne Legionella bacteria detection while showering. An aerosolization chamber was developed to generate controlled and reproducible L. pneumophila aerosols. This tool allowed the identification of the liquid impingement method as the most appropriate one for collecting airborne Legionella bacteria. The culturable fraction of airborne L. pneumophila recovered with the liquid impingement principle was 4 and 700 times higher compared to the impaction and filtration techniques, respectively. Moreover, the concentrations of airborne L. pneumophila in the impinger fluid were on average 7.0 x 10(5) FISH-cells m(-3) air with the fluorescent in situ hybridization (FISH) method versus 9.0 x 10(4) CFU m(-3) air with the culture method. These results, recorded under well-controlled conditions, were confirmed during the field experiments performed on aerosols generated by hot water showers in health institutions. This new approach may provide a more accurate characterization of aerobiocontamination by Legionella bacteria. 相似文献