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151.
The aim of this work is to use GIS integration data to characterize sedimentary processes in a SubTropical lagoon environment. The study area was the Cananéia Inlet estuary in the southeastern section of the Cananéia Lagoon Estuarine System (CLES), state of S?o Paulo, Brazil (25°03′S/47°53′W). The area is formed by the confluence of two estuarine channels forming a bay-shaped water body locally called “Trapandé Bay”. The region is surrounded by one of the most preserved tracts of Atlantic Rain Forest in Southwestern Brazil and presents well-developed mangroves and marshes. In this study a methodology was developed using integrated a GIS database based on bottom sediment parameters, geomorphological data, remote sensing images, Hidrodynamical Modeling data and geophysical parameters. The sediment grain size parameters and the bottom morphology of the lagoon were also used to develop models of net sediment transport pathways. It was possible to observe that the sediment transport vectors based on the grain size model had a good correlation with the transport model based on the bottom topography features and Hydrodynamic model, especially in areas with stronger energetic conditions, with a minor contribution of finer sediments. This relation is somewhat less evident near shallower banks and depositional features. In these regions the organic matter contents in the sediments was a good complementary tool for inferring the hydrodynamic and depositional conditions (i.e. primary productivity, sedimentation rates, sources, oxi-reduction rates).  相似文献   
152.
The problem of toxic smoke in case of an accident with fire scenario is particularly severe in long tunnels and immediate effects from combustion product exposure often include fatalities. Notwithstanding extensive studies on fire simulation in tunnel, there is still a substantial lack of information on the different toxic products from combustion of light or heavy vehicles. In particular, there is a need for reliable test methods suitable to provide toxic products yields connected to defined accidental fire scenarios. In this paper, experimental runs in a laboratory scaled tunnel, simulating accidental fires of different heat release rates allowed firstly to characterize the thermal profiles in pool and car fires and to compare results by an analytical pool fire model. Results were compared as well with those obtained in a real scale tunnel, so as to quantitatively assess the scaling effect. A series of experiments was performed simulating an accidental scenario including pool fire from collision between a light vehicle and a HazMat heavy vehicle. An extensive set of experimental data allowed performing with good accuracy and reproducibility a complete characterization of toxic gases from car model fires, together with carbon monoxide and oxygen trends. The results obtained under different heat release rates allowed evidencing the dependence of the yields of toxic gases upon the considered scenario. Based on the intrinsic toxicity data of identified compounds, it is possible to draw practical conclusions, useful to assess the potential hazard associated to exposure to toxic smoke in road tunnel.  相似文献   
153.
Plant domestication can modify flavonoid concentration, generating a decrease in plants subjected to cultivation, but when cultivated plants are transferred to their original wild area, flavonoids can be recovered. In this framework, a native shrub from Chile, Ugni molinae, has been domesticated due to their high phenolic composition. We hypothesised that plant domestication results in a decrease of flavonoid in cultivated plants, and that when they are exposed to a reciprocal transplant experiment, the flavonoid content can be recovered. Hence, a reciprocal transplant experiment for analysing the flavonoids of cultivated plants transferred to their original wild environments was carried out. Methanolic leaf extracts from two cultivated ecotypes and their respectively wild ancestors were collected for flavonoid analysis. Four flavonols and two isoflavonoids were identified and quantified by liquid chromatography. Results showed differences in flavonoids concentrations between wild (290?µg/g) and cultivated (160?µg/g) plants. Furthermore, when wild plants were transferred to cultivated areas, a reduction in flavonoids of 80?µg/g was observed. Moreover, rutin was the most abundant compound (36.09%) detected by chromatography in Mehuín wild plants. Our results showed that cultivated plants transferred to their respective wild environment presented a capacity of recover myricetin, daidzin and genistin content.  相似文献   
154.
Despite the relative recent move towards inherent safe materials, the relentless drive of consumerism requires increased quantities of dangerous goods to be manufactured, transported, stored and used year on year. The safety and effectiveness of road transport systems is to be considered a strategic goal in particular in those countries, like Italy, in which 80% of goods are transported by this means. In this paper, we face the risk from dangerous good transport by presenting a site-oriented framework for risk assessment and developing a theoretical approach for emergency planning and optimisation. In the first step, we collected field data on a pilot highway and developed a database useful to allow a realistic evaluation of the accident frequency on a given route, by means of multivariate statistical analysis. To this end, we considered both inherent factors (such as tunnels, bend radii, height gradient, slope etc), meteorological factors, and traffic factors (traffic frequency of tank truck, dangerous good truck etc.) suitable to modify the standard national accident frequency. By applying the results to a pilot area, referring to flammable and explosive scenarios, we performed a risk assessment sensitive to route features and population exposed. The results show that the risk associated to the transport of hazardous materials, in some highway stretches, can be at the boundary of the acceptability level of risk set down by the well known F/N curves established in the Netherlands. On this basis, in the subsequent step, we developed a theoretical approach, based on the graph theory, to plan optimal emergency actions. The effectiveness of an emergency planning can normally be evaluated in term of system quickness and reliability. As a case study, we applied the developed approach to identify optimal consistency and localisation in the pilot area of ‘prompt action vehicles’, properly equipped, quick to move and ready for every eventuality. Applying this method results in an unambiguous and consistent selection criterion that allows reduction of intervention time, in connection with technical and economic optimisation of emergency equipment.  相似文献   
155.
This paper deals with the problem of defining the operational tasks, modelling and optimizing of antifire crew and their attempts. Unwanted events are generally modest and easily controlled in their starting phase. This obviously leads to considering that quickness and coordination enhance the possibility of successful fire control. Hence the importance that the first intervention of the factory antifire crew is supported by strong organization and efficiency. Immediate and appropriate response to emergency is essential to minimize severity of accidents, life losses, as well as the potential reduction in the plant future productivity. In approaching internal antifire crew optimization, it is convenient to distinguish a traditional inventory phase, a subsequent optimization and a graphic modelling phase. Optimization criterion is developed according to graph theory, with regard to intervention pathways and to consistency of antifire crew. The proposed graphic model provides, in an immediately readable way, the sequence of operator actions to be followed in order to cope with emergency situations.  相似文献   
156.
The aim of this study is to estimate the distribution of heavy metals in water and in suspended particulates in relation to the observations made on hydrology, concentrations of oxygen, nutrients and chlorophylls in different coastal areas of the Ligurian Sea.

The superficial water samples were collected during the cruise of the R/V “Bannock” in 25 stations placed at different distances from the coast at Alassio, Savona, Genova, Chiavari and Corniglia (between 0.5 and 6.1 nautical miles from the coast). Furthermore water samples were collected at a depth of 10, 20, 30, 50, 75 and 100m, on offshore stations of every transect.  相似文献   
157.
ABSTRACT: Riparian buffers are considered important management options for protecting water quality. Land costs and buffer performance, which are functions of local environmental characteristics, are likely to be key attributes in the selection process, especially when budgets are limited. In this article we demonstrate how a framework involving hydrologic models and binary optimization can be used to find the optimal buffer subject to a budget constraint. Two hydrologic models, SWAT and REMM, were used to predict the loads from different source areas with and without riparian buffers. These loads provided inputs for a binary optimization model to select the most cost efficient parcels to form a riparian buffer. This methodology was applied in a watershed in Delaware County, New York. The models were parameterized using readily available digital databases and were later compared against observed flow and water quality data available for the site. As a result of the application of this method, the marginal utility of incremental increases in buffer widths along the stream channel and the set of parcels to form the best affordable riparian buffer were obtained.  相似文献   
158.
Wet deposition and related rainwater chemistry were studied at the Itatiaia massif, on which is settled the Itatiaia National Park (INP). Samples were simultaneously collected on a weekly basis over 12 months, using automated wet and dry samplers, at the INP-Headquarters (INP-Hq; altitude=820 m) and the Itatiaia Plateau (It-Pt; altitude=2460 m). Conductivity, pH, Na(+), K(+), Mg(2+), Ca(2+), NH(4)(+), Cl(-), NO(3)(-) and SO(4)(2-) were determined in 36 rainwater samples. Volume-weighted mean (VWM) pH was lower at the INP-Hq (4.9) than at the It-Pt (5.3). Very strong correlation between Cl(-) and Na(+) was found for the INP-Hq (r=0.99). At the Itatiaia massif, SO(4)(2-), NO(3)(-), and NH(4)(+) comprised together about 60% of the total inorganic ions and appear to exert the major control on rainwater pH.  相似文献   
159.
Fetal echocardiography was performed during the third trimester in a normal primigravida. The fetal heart was severely affected with the typical cardiac manifestations of Marfan syndrome. The medical history of the father was investigated and a mild form of the syndrome was diagnosed. The neonate died at 2 months of age of congestive heart failure.  相似文献   
160.
The National Weather Service (NWS) forecasts floods at approximately 3,600 locations across the United States (U.S.). However, the river network, as defined by the 1:100,000 scale National Hydrography Dataset‐Plus (NHDPlus) dataset, consists of 2.7 million river segments. Through the National Flood Interoperability Experiment, a continental scale streamflow simulation and forecast system was implemented and continuously operated through the summer of 2015. This system leveraged the WRF‐Hydro framework, initialized on a 3‐km grid, the Routing Application for the Parallel Computation of Discharge river routing model, operating on the NHDPlus, and real‐time atmospheric forcing to continuously forecast streamflow. Although this system produced forecasts, this paper presents a study of the three‐month nowcast to demonstrate the capacity to seamlessly predict reach scale streamflow at the continental scale. In addition, this paper evaluates the impact of reservoirs, through a case study in Texas. Validation of the uncalibrated model using observed hourly streamflow at 5,701 U.S. Geological Survey gages shows 26% demonstrate PBias ≤ |25%|, 11% demonstrate Nash‐Sutcliffe Efficiency (NSE) ≥ 0.25, and 6% demonstrate both PBias ≤ |25%| and NSE ≥ 0.25. When evaluating the impact of reservoirs, the analysis shows when reservoirs are included, NSE ≥ 0.25 for 56% of the gages downstream while NSE ≥ 0.25 for 11% when they are not. The results presented here provide a benchmark for the evolving hydrology program within the NWS and supports their efforts to develop a reach scale flood forecasting system for the country.  相似文献   
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