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881.
Fernanda F. Heleno Maria Eliana L. R. de Queiroz Antônio Augusto Neves Romenique S. Freitas Lêda Rita A. Faroni André Fernando De Oliveira 《Journal of environmental science and health. Part. B》2013,48(2):94-101
The effect of ozone fumigation on the reduction of difenoconazole residue on strawberries was studied. Strawberries were immersed in 1.0 L of aqueous solution containing 400 μL of the commercial product (250 g L?1 of difenoconazole) for 1 min. Then, they were dried and exposed to ozone gas (O3) at concentrations of 0.3, 0.6 and 0.8 mg L?1 for 1 h. The ozone fumigation treatments reduced the difenoconazole residue on strawberries to concentrations below 0.5 mg kg?1, which corresponds to a 95% reduction. The strawberries treated with ozone and the control group, which was not treated with ozone, were stored at 4°C for 10 days. Some characteristics of the fruit were monitored throughout this period. Among these, pH, weight loss and total color difference did not change significantly (P > 0.05). The fumigation with ozone significantly affected the soluble solids, titratable acidity and ascorbic acid content (vitamin C) of the strawberries preventing a sharp reduction of these parameters during storage. 相似文献
882.
Maria Widerszal-Bazyl Dorota Żołnierczyk 《International journal of occupational safety and ergonomics》2013,19(1):29-41
This study investigates whether a consistent relationship exists between computerization and job control. It also examines the role of job control as a predictor of stress symptoms typical for data entry and word processing (VDU) work. Two groups of VDU users and two comparable non-VDU-user groups took part in this study. A special questionnaire made it possible to assess global job control and four indexes of control related to specific aspects of work (control over choice of tasks and methods, control over time frame, control related to one’s skill, and control related to participation in the decision-making process). Results did not show an unequivocal relation between computerization and the latitude of control. The latitude of control depends on the task performed and the aspect of control we are considering. Regression analyses showed that global control is a good predictor of job satisfaction, some mood disturbances, and visual complaints. The other aspects of control are related in a variety of ways to stress symptoms. The role of a Type A behavior pattern in the relationship between job control and stress symptoms varies depending on which aspect of control is being considered. It was concluded that because of the high functional differences between various aspects of control, it is better to avoid using the concept of global control and, when possible, apply specific indexes of control. 相似文献
883.
Carolina Lourencetti Mary R. R. De Marchi Maria L. Ribeiro 《Journal of environmental science and health. Part. B》2013,48(10):949-958
This study reports the influence of sugar cane vinasse on the persistence, sorption and leaching potential of diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea), hexazinone (3-cyclohexyl-6-(dimethylamino)-1-methyl-1,3,5-triazine-2,4-dione) and tebuthiuron (1-(5-tert-butyl-1,3,4-thiadiazol-2-yl)-1,3-dimethylurea) in both a clay and sandy soil from a tropical area of Brazil. The experiments were conducted out under controlled laboratory conditions. The addition of sugarcane vinasse to soil influenced the persistence and sorption of the herbicides in both the studied clay and sandy soils, with a considerable decrease in the diuron DT50 values in clay soil. The Ground Water Ubiquity Score (GUS) Index classifies the herbicides as leachers in both soils and treatments, with the exception of diuron, which is classified as a non-leacher in clay soil-vinasse and as a transient herbicide in sandy soil. These results suggest that special attention should be given to areas such as those where the sandy soil was collected in this study, which is a recharge area of the Guarani Aquifer and is likely to experience groundwater contamination due to the high leaching potential of the applied pesticides. 相似文献
884.
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
885.
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
886.
887.
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
888.
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
889.
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
890.
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