全文获取类型
收费全文 | 1925篇 |
免费 | 21篇 |
国内免费 | 29篇 |
专业分类
安全科学 | 80篇 |
废物处理 | 131篇 |
环保管理 | 175篇 |
综合类 | 300篇 |
基础理论 | 325篇 |
污染及防治 | 634篇 |
评价与监测 | 188篇 |
社会与环境 | 131篇 |
灾害及防治 | 11篇 |
出版年
2023年 | 30篇 |
2022年 | 66篇 |
2021年 | 77篇 |
2020年 | 37篇 |
2019年 | 33篇 |
2018年 | 82篇 |
2017年 | 79篇 |
2016年 | 103篇 |
2015年 | 61篇 |
2014年 | 94篇 |
2013年 | 190篇 |
2012年 | 132篇 |
2011年 | 140篇 |
2010年 | 102篇 |
2009年 | 83篇 |
2008年 | 119篇 |
2007年 | 96篇 |
2006年 | 106篇 |
2005年 | 88篇 |
2004年 | 62篇 |
2003年 | 39篇 |
2002年 | 32篇 |
2001年 | 13篇 |
2000年 | 6篇 |
1999年 | 11篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 5篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1979年 | 2篇 |
1966年 | 2篇 |
1962年 | 2篇 |
1961年 | 2篇 |
1960年 | 2篇 |
1959年 | 2篇 |
1953年 | 2篇 |
1936年 | 2篇 |
1935年 | 2篇 |
1934年 | 2篇 |
1928年 | 2篇 |
排序方式: 共有1975条查询结果,搜索用时 15 毫秒
881.
Elisabeth Krausmann Ana Maria Cruz Bastien Affeltranger 《Journal of Loss Prevention in the Process Industries》2010,23(2):242-248
This study describes the results of a field trip to the area affected by the 12 May, 2008, Wenchuan earthquake to analyse its impact on industrial facilities. The damage severity correlates well with the age of the plant, with older facilities having suffered more extensive and severe damage than those built more recently according to the latest design codes. The main cause of worker death and injury was the collapse of warehouses, office and manufacturing buildings. This concerned mostly concrete structures with insufficient confinement or poor reinforcement. The falling debris resulted in equipment damage and loss, as well as pipe severing and crushing. Pipes were also severed or bent when connected tanks were displaced or buildings collapsed. Numerous hazardous-materials releases occurred with spills being the dominant accident scenario. In some sites soil–liquefaction induced damage was evident, highlighting the need to consider potential site effects when selecting the location for a facility. The impact of the Wenchuan earthquake on chemical facilities confirms the findings from other earthquakes in terms of typical Natech damage and failure modes, as well as of hazardous-materials release potential and mechanisms. 相似文献
882.
Estimating tree bole volume using artificial neural network models for four species in Turkey 总被引:2,自引:0,他引:2
Ramazan Özçelik Maria J. Diamantopoulou John R. Brooks Harry V. Wiant 《Journal of environmental management》2010,91(3):742-753
Tree bole volumes of 89 Scots pine (Pinus sylvestris L.), 96 Brutian pine (Pinus brutia Ten.), 107 Cilicica fir (Abies cilicica Carr.) and 67 Cedar of Lebanon (Cedrus libani A. Rich.) trees were estimated using Artificial Neural Network (ANN) models. Neural networks offer a number of advantages including the ability to implicitly detect complex nonlinear relationships between input and output variables, which is very helpful in tree volume modeling. Two different neural network architectures were used and produced the Back propagation (BPANN) and the Cascade Correlation (CCANN) Artificial Neural Network models. In addition, tree bole volume estimates were compared to other established tree bole volume estimation techniques including the centroid method, taper equations, and existing standard volume tables. An overview of the features of ANNs and traditional methods is presented and the advantages and limitations of each one of them are discussed. For validation purposes, actual volumes were determined by aggregating the volumes of measured short sections (average 1 meter) of the tree bole using Smalian's formula. The results reported in this research suggest that the selected cascade correlation artificial neural network (CCANN) models are reliable for estimating the tree bole volume of the four examined tree species since they gave unbiased results and were superior to almost all methods in terms of error (%) expressed as the mean of the percentage errors. 相似文献
883.
884.
Pedro Daleo Juan Alberti Maria Soledad Avaca Maite Narvarte Paulina Martinetto Oscar Iribarne 《Marine Biology》2012,159(10):2359-2365
Feeding decisions under predation risk can be a key in the life of scavenger organisms, and tuned recognition of predation alarm cues and flexibility in the response are fundamental. The effect of injured conspecifics on the response behavior of the whelk Buccinanops globulosum to feeding opportunities was experimentally evaluated in a Patagonian Bay (40°45′S, 64°56′W, Argentina) in September 2010. The effect of sex, size, body condition, or starvation on anti-predatory behavior was assessed. The number of B. globulosum feeding on carrion was reduced by half when damaged conspecifics were present. Smaller, lighter, and starved individuals responded less to the presence of damaged conspecifics. These results indicate that, under natural conditions, feeding avoidance after detecting damaged conspecifics is a common and important anti-predatory strategy of B. globulosum and show that morphology and starvation are significant factors in the context of the trade-off between feeding and avoiding predation risk. 相似文献
885.
José S. Antunes do Carmo Maria G. Neves Mechteld ten Voorde 《Journal of Coastal Conservation》2011,15(1):99-112
Multifunctional artificial reefs are submerged breakwaters that serve several purposes. As well as protecting the local coastline,
they enhance surfing possibilities and/or increase the environmental value of the area where they are situated. Multifunctional
artificial reefs (MFARs) have some promising new aspects, too: first, they provide an unimpaired visual amenity, and second,
they can offer tourist and economic benefits by improving the surfing conditions. Regarding the functionality of an MFAR,
much research has been carried out on surfability, i.e. whether a wave is good for surfers. However, no research has yet been
done on the influence of the submergence and the length of the reef slope on the breaker type, even though this is important
for the design of the reef in terms of surfability. A preliminary design was achieved step by step, making use of the theory
and state of the art of multifunctional artificial reefs (Voorde et al. 2009a, 2009b). This reef geometry was then used as an initial design in physical and numerical tests. These were performed to ascertain
the capacity of a multifunctional reef to serve as a submerged breakwater and so protect the local coastline of Leirosa, Portugal,
and improve the local surfing possibilities. This paper describes the numerical study conducted to analyze the influences
of the main relevant parameters in the vertical plane, namely: the height, the submergence, and the length and slope of the
reef. The investigation was conducted using the COBRAS-UC numerical model in the vertical plane and the main results and conclusions
are described and presented; a brief discussion and some recommendations for future work are also included. 相似文献
886.
Maria Luiza D.P. Godoy José Marcus Godoy Luiz Alfredo Roldão Daniela S. Soluri Raquel A. Donagemma 《Atmospheric environment (Oxford, England : 1994)》2009,43(14):2366-2374
The metropolitan area of Rio de Janeiro is one of the twenty biggest urban agglomerations in the world, with 11 million inhabitants in the metropolitan area, and has a high population density, with 1700 hab. km?2. For this aerosol source apportionment study, the atmospheric aerosol sampling was performed at ten sites distributed in different locations of the metropolitan area from September/2003 to December/2005, with sampling during 24 h on a weekly basis. Stacked filter units (SFU) were used to collect fine and coarse aerosol particles with a flow rate of 17 L min?1. In both size fractions trace elements were analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) as well as water-soluble species by Ion-Chromatography (IC). Also gravimetric analysis and reflectance measurements provided aerosol mass and black carbon concentrations. Very good detection limits for up to 42 species were obtained. Mean annual PM10 mass concentration ranged from 20 to 37 μg m?3, values that are within the Brazilian air quality standards. Receptor models such as principal factor analysis, cluster analysis and absolute principal factor analysis were applied in order to identify and quantify the aerosol sources. For fine and coarse modes, circa of 100% of the measured mass was quantitatively apportioned to relatively few identified aerosol sources. A very similar and consistent source apportionment was obtained for both fine and coarse modes for all 10 sampling sites. Soil dust is an important component, accounting for 22–72% and for 25–48% of the coarse and fine mass respectively. On the other hand, anthropogenic sources as vehicle traffic and oil combustion represent a relatively high contribution (52–75%) of the fine aerosol mass. The joint use of ICP-MS and IC analysis of species in aerosols has proven to be reliable and feasible for the analysis of large amount of samples, and the coupling with receptor models provided an excellent method for quantitative aerosol source apportionment in large urban areas. 相似文献
887.
Mónica A. Silva Rui Prieto Sara Magalh?es Maria I. Seabra Ricardo S. Santos Philip S. Hammond 《Marine Biology》2009,156(2):179-192
Very little is known about the ecology of common bottlenose dolphins (Tursiops truncatus) living in oceanic waters. This study investigated the ranging and residence patterns of bottlenose dolphins occurring in
the Azores (Portugal), the most isolated archipelago in the North Atlantic. Data were collected during standardized boat-based
surveys conducted over a 6-year period in an area of approximately 5,400 km2 (main study area). To investigate the extent of movements of individual animals, non-systematic surveys were also conducted
outside this area. Only 44 individuals out of 966 identified were frequently sighted within and between years. The remaining
individuals were either temporary migrants from within or outside the archipelago, or transients. Resident dolphins showed
strong geographic fidelity to the area. Long-distance movements (of almost 300 km), consistent with foraging or exploratory
trips, were observed among non-resident dolphins. Home range size was estimated for 31 individuals sighted ≥10 times. Range
areas of these dolphins varied in size and location, but considerable overlap was observed in the areas used, suggesting the
absence of habitat partitioning between resident and non-resident dolphins. Estimates of home range size of bottlenose dolphins
in the Azores were found to be considerably larger than those previously reported for this species. It is hypothesized that
dolphins living in the Azores carry out extensive movements and have large home ranges in response to the lower density and
patchy distribution of prey compared to other areas. The extensive ranging behaviour and the lack of territoriality provide
an opportunity for interbreeding between dolphins associated with different islands, thus preventing genetic differentiation
within the population of the Azores. 相似文献
888.
Halley M. S. Durrant Graeme F. Clark Symon A. Dworjanyn Maria Byrne Emma L. Johnston 《Marine Biology》2013,160(8):1903-1911
Ocean warming and acidification are co-occurring stressors likely to affect marine biota through climate-driven change to the ocean. We investigated the effects of increased temperature and lowered pH, solely and in combination, on the growth of the endemic Australian bryozoan, Celleporaria nodulosa. Two temperatures and three pH levels were fully crossed in experimental treatments performed in winter 2008 (August) and summer 2009 (February/March). Fragments of C. nodulosa colonies (clones) were collected from Coffs Harbour, NSW, Australia, (30°18′S, 153°09′E) and elongation of colonies was assessed periodically over a 12-day incubation period. Lowered pH in winter significantly decreased growth. Elevated temperatures during the summer significantly impeded the growth of bryozoan colonies, possibly masking the effect of ocean acidification and discovering a maximal thermal tolerance at around 27 °C for C. nodulosa. The effects of decreased pH and increased temperature may be seasonally dependent and particularly acute during the summer months. Thermal stress may in fact be the initial stressor before ocean acidification, negatively affecting organisms in such a way that they are unable to survive before feeling the effects of ocean acidification. 相似文献
889.
Isequiel Dos S. Mendes Maria Olímpia Oliveira Rezende 《Journal of environmental science and health. Part. B》2013,48(5):374-380
The herbicidal potential of aqueous extracts prepared from leaves and seeds of Canavalia ensiformis was tested by applying them postemergence to the crop weeds Ipomoea grandifolia and Commelina benghalensis. Considering the possible objective of using this bioherbicide on soybean fields, the extracts were also tested for deleterious effects on both transgenic and conventional soybean (Glycine max). In addition, the concentrations of four phenolic compounds and alkaloids with allelopathic properties in these extracts were estimated by high-performance liquid chromatography. The seed extract at concentrations of 25 g L?1 and 50 g L?1 was the most efficient postemergent bioherbicide. By applying these extracts, the development of the weed seed was progressively hindered until no recovery was observed. The application of 3.5 mL of crude extract on a plant that takes 30 days after germination of the seed to develop is sufficient for full control of the species within 5 days. Since both Ipomoea grandifolia and Commelina benghalensis are broadleaf dicotyledons, it is possible that other species with these characteristics can also be controlled or suffer the same effects under the action of the seed extract, if the same volume and mode of application are used. The selectivity of the treatments with 25 g L?1 and 50 g L?1 was assessed on transgenic and conventional cultivars. The treatments did not visibly affect the soybean cultivars, which developed normally during the observation period that continued up to 15 days after the death of the weeds. 相似文献
890.
Joan Colón Maria Mestre-Montserrat Ignasi Puig-Ventosa Antoni Sánchez 《Waste management (New York, N.Y.)》2013,33(5):1097-1103
In modern societies, disposable diapers constitute a significant percentage of municipal solid wastes. They have been traditionally landfilled or incinerated as only limited recycling processes are being implemented in some parts of Europe. With the implementation of separated collection systems for the organic fraction of municipal solid wastes (OFMSWs) and the need to preserve the environment, compostable diapers have appeared in the market to avoid the main environmental impacts associated to non-biodegradable disposable diapers. In this study, a full-scale composting of door-to-door collected OFMSW with a 3% (w/w) of compostable diapers has also been carried out. Previously, lab-scale experiments confirmed that almost 50% of carbon of compostable diapers is emitted as CO2 under aerobic controlled conditions. The results obtained at full-scale demonstrate that both the composting process and the final end product (compost) are not altered by the presence of compostable diapers in crucial aspects such as pathogenic content, stability and elemental composition (including nutrients and heavy metals). The main conclusion of this study is that the collection of the OFMSW with compostable diapers can be a new way to transform this waste into high-quality compost. 相似文献