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71.
In the aftermath of catastrophic natural disasters such as hurricanes, tsunamis and earthquakes, emergency management agencies come under intense pressure to provide temporary housing to address the large‐scale displacement of the vulnerable population. Temporary housing is essential to enable displaced families to reestablish their normal daily activities until permanent housing solutions can be provided. Temporary housing decisions, however, have often been criticized for their failure to fulfil the socioeconomic needs of the displaced families within acceptable budgets. This paper presents the development of (1) socioeconomic disruption metrics that are capable of quantifying the socioeconomic impacts of temporary housing decisions on displaced populations; and (2) a robust multi‐objective optimization model for temporary housing that is capable of simultaneously minimizing socioeconomic disruptions and public expenditures in an effective and efficient manner. A large‐scale application example is optimized to illustrate the use of the model and demonstrate its capabilities ingenerating optimal plans for realistic temporary housing problems.  相似文献   
72.
Small disasters are usually the product of climate variability and climate change. Analysis of them illustrates that they increase difficulties for local development—frequently affecting the livelihoods of poor people and perpetuating their level of poverty and human insecurity—and entail challenges for a country's development. In contrast to extreme events, small disasters are often invisible at the national level and their effects are not considered as relevant from a macroeconomic standpoint. Nevertheless, their accumulated impact causes economic, environmental and social problems. This paper presents the results of an evaluation of the DesInventar database, developed in 1994 by the Network for Social Studies in Disaster Prevention in Latin America. In addition, it proposes a new version of the Local Disaster Index developed in 2005 within the framework of the Disaster Risk and Management Indicators Program for the Americas, with the support of the Inter‐American Development Bank.  相似文献   
73.
The concentrations of metals (Fe, Zn, Cu, Cr, Pb, Cd, Ni, Mn and Co) in 140 street dust samples were collected from Aqaba city, Jordan. These samples were determined using flame atomic absorption spectrophotometry after digestion with aqua regia. The highest levels of metal concentrations were found in the samples from heavy traffic. While the lowest levels of metal ions were noted in the street dust samples from hospital and health centers and school gardens. The results of this study were compared with several cities around the world. The levels of the metal concentrations found were generally below the mean world-wide values of street dust samples. Metal values in urban street dust samples were several times higher than the control levels. The statistical analyses were applied to the data matrix to determine the analytical results and to identify the possible source of pollution in the studied area. Correlations between the metal concentrations of the street dust samples were obtained. Factor analysis showed that the area was mainly influenced by three sources, namely lithogenic, traffic, and industrial.  相似文献   
74.
We tested to what extent mean sea surface temperature, geometric constraints in range size frequency distributions (the mid-domain effect) and geographical coastline distance to the equator are related to species richness of coastal Mytilidae and Ostreidae in the Pacific and Atlantic coasts of South America (excluding islands). The location and magnitude of the peaks in species richness, as well as the shape of the pattern, varied between oceans. Results were not biased by spatial autocorrelation, although strong multicollinearity among predictor variables was detected. However, these regional-extent regression models suggest differences in the causal factors that explain richness gradients of studied bivalves in South American coasts, most likely related to historical events such as the Southeastern Pacific Pleistocene mass extinction of bivalves. Our results reinforced the conclusion that there is no single best explanatory cause for the latitudinal gradient in species richness and showed that the correlative approach is not useful when predictor variables are strongly correlated.  相似文献   
75.
The leaves of date palms were evaluated as a possible biomonitor of heavy metal contamination in Ma’an city, Jordan. Concentrations of (Fe), (Pb), (Zn), (Cu), (Ni), and (Cr) were determined in washed and unwashed leaves and soil samples collected from different sites with different degrees of metal contamination (urban, suburban, industrial, highway and rural sites); separate leaves were taken from outside the city to be used as a control sample. Samples collected from industrial sites were found to have high concentrations of all metals except those of Cu, Ni and Pb, which were found at high levels in the highway site samples which is associated with the road traffic. The difference between unwashed and washed samples showed that metal pollutants exist as contaminants, particularly Pb, Zn and Ni, which varied in concentration, depending on the source of the metal.  相似文献   
76.
The effect of HOx radicals (OH and HO2) and ozone (O3) on aerosol formation and aging has been studied. Experiments were performed in presence as well as in absence of oxygen in a flow-through chamber at 299 K for three organic precursor gases, isoprene, α-pinene and m-xylene. The HOx source was the UV photolysis of humidified air or nitrogen and was measured with a GTHOS (Ground-based Tropospheric Hydrogen Oxides Sensor). The precursor gases concentration was monitored with an online GC-FID. The aerosol mass was then quantified by a Tapered Element Oscillating Microbalance (TEOM). Typical oxidant mixing ratios were (0–4.5) ppm for O3, 200 pptv for OH and 3 ppbv for HO2. A simple kinetics model is used to infer the aerosol production mechanism. In the present of O3 (or O2), the SOA yields were 0.46, 0.036 and 0.12 for α-pinene with an initial concentration of 100 ppbv (RH = 37%), isoprene with an initial concentration of 177 ppbv (RH = 50%) and m-xylene with an initial concentration of 100 ppbv (RH = 37%), respectively. When the chosen precursor gases reacted with HOx in the absence of O3, the maximum SOA yields were significantly increased by factors of 1.6 for isoprene 1.1 for α-pinene, and 3 for m-xylene respectively. The comparison of the calculated and measured potential aerosol mass concentrations as function of time shows that presence of ozone or oxygen can influence the aerosol yield and the absence of ozone or oxygen in the system resulted in high concentrations of its organic aerosol products.  相似文献   
77.
Reuse of mining wastewater in agricultural activities in Jordan   总被引:1,自引:0,他引:1  
A pilot study was completed in the Al-Abyad area near phosphate mining activity in Jordan. Six plots of 50 m2 each were planted with two types of plant species (Zea mays spp. and Medicago lupulina spp.) and irrigated using three types of water (fresh groundwater, mine wastewater, and hydride water consisting of 50% fresh and 50% mine wastewater) to investigate the suitability of utilizing mine wastewater for food production in the area. Water, soil and plant sampling was completed for each plot over different time intervals and analyzed for heavy metal (Cr+6, Ni+2, Zn+2 and Pb+2) in addition to major ionic composition of the water used for irrigation. Crop yield was estimated at the end of the experiment. Plots irrigated with mine wastewater showed slightly higher heavy metals concentrations and soil salinity during the experiment period was higher for plots irrigated with mine wastewater compared to plots irrigated with fresh water, and it was uniform through the upper 45 cm of the soil profile due to the high amount of irrigation water used during the experiment. Crop yield was inversely proportional to salinity as an increase of salinity by 2-folds resulted in reducing yield by almost 50%. However, no risk of heavy metals contamination was found in plants and soil. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
78.
Abstract

The binding site interactions of IHSS humic substances, Suwannee River Humic Acid, Suwannee River Fulvic Acid, Nordic Fulvic Acid, and Aldrich Humic Acid with various metals ions and a herbicide, methyl viologen were investigated using fluorescence emission and synchronous‐scan spectroscopy. The metal ions used were, Fe(III), Cr(III), Cr(VI), Pb(II), Cu(II) and Ni(II). Stern‐Volmer constants, KSV for these quenchers were determined at pH 4 and 8 using an ionic strength of 0.1M. For all four humic substances, and at both pH studied, Fe(III) was found to be the most efficient quencher. Quenching efficiency was found to be 3–10 times higher at pH 8. The bimolecular quenching rate constants were found to exceed the maximum considered for diffusion controlled interactions, and indicate that the fluorophore and quencher are in close physical association. Synchronous‐scan spectra were found to change with pH and provided useful information on binding site interactions between humic substances and these quenchers.  相似文献   
79.
BACKGROUND: Wastewater from textile industry contains various contaminants such as dyes, surfactants and heavy metals. Textile dyes have synthetic origin and complex aromatic molecular structures that make them difficult to biodegrade when discharged in the ecosystem. The objective of this study was to examine the decolourisation of textile effluents containing cationic dyes by filtration-adsorption on wood sawdust from two different origins; fir as an example of a conifer tree, and beech as an example of a deciduous one, and to explain the adsorption mechanism. METHODS: The process of dye removal was applied to a synthetic effluent in batch mode. Adsorption experiments were performed by suspending sawdust in the effluent and analyzing the supernatant by spectrophotometry. The effectiveness of the treatment process was evaluated by measuring coloration. RESULTS AND DISCUSSION: Experimental results showed a significant potential for wood sawdust, especially coniferous sawdust, to remove cationic dyes from textile effluents. Adsorption kinetics was influenced by the initial dye concentration, nature and amount of sorbent as well as sorbent particle size. The adsorption followed a pseudo first-order kinetics. For both basic dyes, the Langmuir adsorption equation showed a better fit than the Freundlich equation. CONCLUSION: Filtration-adsorption using an inexpensive and readily available biosorbent provided an attractive alternative treatment for dye removal, and it does not generate any secondary pollution. Recommendations and Perspectives. Laboratory studies provide promising perspectives for the utilization of wood sawdust as renewable adsorbent for reducing pollution while enhancing the reuse of textile effluents. However, the treatment process needs to be applied to the other textile dye classes in order to be used on an industrial scale.  相似文献   
80.
Particulate pollution has been clearly linked with adverse health impacts from open fire cookstoves, and indoor air concentrations are frequently used as a proxy for exposures in health studies. Implicit are the assumptions that the size distributions for the open fire and improved stove are not significantly different, and that the relationship between indoor concentrations and personal exposures is the same between stoves. To evaluate the impact of these assumptions size distributions of particulate matter in indoor air were measured with the Sioutas cascade impactor in homes using open fires and improved Patsari stoves in a rural Purepecha community in Michoacan, Mexico. On average indoor concentrations of particles less than 0.25 μm were 72% reduced in homes with improved Patsari stoves, reflecting a reduced contribution of this size fraction to PM2.5 mass concentrations from 68% to 48%. As a result the mass median diameter of indoor PM2.5 particulate matter was increased by 29% with the Patsari improved stove compared to the open fire (from 0.42 μm to 0.59 μm, respectively). Personal PM2.5 exposure concentrations for women in homes using open fires were approximately 61% of indoor concentration levels (156 μg m?3 and 257 μg m?3 respectively). In contrast personal exposure concentrations were 77% times indoor air concentration levels for women in homes using improved Patsari stoves (78 μg m?3and 101 μg m?3 respectively). Thus, if indoor air concentrations are used in health and epidemiologic studies significant bias may result if the shift in size distribution and the change in relationship between indoor air concentrations and personal exposure concentrations are not accounted for between different stove types.  相似文献   
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