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431.
One of the most pressing issues in studying the impacts of sea level rise (SLR) triggered by climate change is understanding the development of the hazard of permanent coastal flooding. The issue persists because available approaches are based on the mapping of the inundated area where they explore the coastal flooding development across terrain elevations, that is—horizontally. In addition, they overlook the existing structures along or in the vicinity of the coastline, which have inherent hydraulic properties that may affect the development of such flooding. The purpose of this study is to develop a novel approach for assessing the development of permanent coastal flooding due to SLR at cross sections along the coastline, that is—vertically, in full consideration of underlying hydraulic properties of the existing coastline. An approach was developed using analogy of existing coastline to a contiguous weir. This approach was named crestline approach and was developed as a four step GIS-based approach that could be applied at any coastal zone. An example application on one of the top ranked cities in the world prone to the SLR threat has been provided to illustrate exactly how to apply the crestline approach. The novelty of this approach lies in its ability to accurately identify the specific locations where coastal flooding will initiate, in full consideration of existing natural/manmade coastal structures. This study is significant for the opportunities it provides to analysts and decision makers to better understand the development of permanent coastal flooding.  相似文献   
432.
Urban water authorities and water planers in many countries are struggling to satisfy the growing urban water and sanitation demands, while at the same time achieving sustainability of the urban water system. This research focused on the assessment of the environmental impact of today's Alexandria's urban water system and on the identification of options to improve the sustainability of the system. Therefore, a life cycle assessment (LCA) methodology was used. The urban water system was modelled using SimaPro software, and the impacts of various options on the system were analyzed based on the Eco-indicator 99 assessment method. The results show that the highest impact in today's system is generated by the disposal of primary treated wastewater (68% of the total impact) and by high-energy-consuming water treatment plants (18% of the total impact). The research assessed different scenarios for improving the environmental performance of the system and a paradigm shift (decentralization and separation at-source of different kinds of household wastewater) was found to be the preferred long-term scenario.  相似文献   
433.
Regional Environmental Change - Many coasts are eroding. In the Comoros, as in many other small island developing states (SIDS), communities frequently respond to coastal erosion by building...  相似文献   
434.
In the present work, the promising bioinformatic tools, based on structure–affinity analysis, allowed to screen several pesticides supposed to bind to the insect immune Phenoloxidases (PO). First, the binding of aminoparathion, a reference compound, to the PO was structurally (3D) validated in accordance with previous reports. Second, using the same docking conditions, a range of pesticides was checked for their binding ability to the crystal 3D structure (PDB 3HSS) of the insect Manduca sexta (Lepidoptera) PO. The obtained data showed that many of the tested pesticides were able to bind, in silico, to M. sexta PO. The combination of in vitro (chemical and biochemical) and in silico (automated docking) approaches was found advantageous to elucidate the behavior of phenolic pesticides as substrate-analogues when binding to the active site of insect POs. Our findings emphasize new ecotoxicological aspects of pesticide residues in the agro-chemical and environmental circles.  相似文献   
435.
Abstract

Human serum transferrin (HSTF), human serum albumin (HSA) and rat serum were compared for their interaction with AlCl3 , in a Tris‐HCl buffer solutions (pH 7.4). The AlCl3 was tested in series of concentrations in the range of 50 μM up to 500 μM . HSTF, HSA and their 1:1 mixture and rat serum were incubated at 37°C with series of AlCl3 concentrations. The protein profile of the incubated solutions were compared to control using SDS‐PAGE and FPLC tests. The results indicated that HSTF was more specifically responsive to AlCl3showing a characteristic increase in its UV absorption, peak and area dimensions. Simultaneously, HSA was less affected, but it showed a significant shift with an increase in molecular weight accompanied with a change in its profile. The respective bands of transferrin and albumin in rat serum behaved similarly. The SDS‐PAGE and FPLC data coincided and confirmed the preferential affinity of HSTF to bind with Al3+ . These results support the suggestion of using HSTF for monitoring levels of Al3+ in human blood samples of exposed population. The importance of further developing such a biomarker is the increased demand for early detection of the hazardous levels of Al3+ in relation to its long term neurotoxic adverse effects.  相似文献   
436.
A laboratory study using a bench scale model of two units operation involving coagulation process with Moringa oleifera seeds extract as a coagulant and filtration process using hollow fibre microfiltration membrane, was adopted to treat Air Hitam Sanitary Landfill leachate in Puchong, Malaysia. The performance of the microfiltration membrane in pretreated sanitary landfill leachate treatment was investigated through a continuous process. The leachate sample was passed through conventional coagulation process before being filtered through a hollow fibre microfiltration membrane of 0.1 μm surface pores. The hollow fibre microfiltration membrane decreased the turbidity, colour, total suspended solids, total dissolved solids and volatile suspended solids in the leachate by 98.30, 90.30, 99.63, 14.71 and 20%, respectively. The results showed that microfiltration is capable of removing high percentage of solids from leachate and might be considered as a polishing stage after on-site biological treatment for sanitary landfill leachate.  相似文献   
437.
Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cr, Cu, Cd, Pb, Zn, and Hg) was investigated in muscle, gill, and liver in two different fish species seasonally collected in El-Mex Bay (autumn 2004-summer 2005). In order to evaluate the pollution status of the Bay, the concentrations of the selected metals in the labile and total fractions were analysed in sediment samples collected from eight sites in El-Mex Bay during autumn 2004. Also, the Index of Geoaccumulation (Igeo) for the sediment was estimated. The total and labile fractions of the selected metals in sediment samples were 15.2 and 62.8 μg g-1 dw for Cu, 1.8 and 5.0 μg g-1 dw for Cd, 79.1 and 130.3 μg g-1 dw for Zn, 0.2 and 1.2 μg g-1 dw for Hg, 35.8 and 93.0 μg g-1 dw for Pb, and 13.9 and 31.0 μg g-1 dw for Cr. The concentrations of all metals were lower in flesh than those recorded in liver and gill due to their physiological roles. The metal pollution index for fish was calculated. Health hazard calculations for the contaminated sediments and fish consumption were calculated to evaluate the effect of pollution on health.  相似文献   
438.
Water samples were taken from 12 stations at El-Dikheila Harbour, El-Mex Bay, Western Harbour, Qayet Bey outfall, Eastern Harbour, El-Ibrahemiya, Gleem, Sidi Bishr and Mandara, during January, April, August and November 1995. the area lies between latitude 31˚ 8' and 31˚ 17' North and longitude 29˚ 47' and 30˚ East. the annual mean of chlorinity (11.69-20.5%0), pH (7.9-8.3), reactive phosphate (0.31-2.24 μM), nitrite (0.18-1.98 μM), oxidizable organic matter (1.97-8.95 mgO2 1-1), iodide (21.14-46.74 μg 1-1) and iodate (4.61-2.04 μg 1-1) were measured. Iodide content in water is three times higher than iodate. Iodide is positively correlated with chlorinity (r=0.65) and iodate (r=0.45), while it is negatively correlated with nitrite (r= -0.72), oxidizable organic matter (r= -0.55) and pH (r= -0.4).  相似文献   
439.
The biodegradation of hydrocarbons was performed in refinery wastewater obtained by natural microbial flora in Ismailia canal water. About 87% of hydrocarbons were degraded after 9 days under simulated natural conditions. It was found that the addition of fuel oil to the canal water, which already contained significant amounts of refinery wastewater, retarded biological degradation. Percentage of degradation was found to be 67%. This increase in the hydrocarbons concentration affects dramatically on the generation rate of microorganisms present naturally in canal water.  相似文献   
440.
Lake Edku is one of the Nile Delta shallow brackish water coastal lagoons with communications with the southeastern Mediterranean.

Sediment samples were recovered from the top 10 cm of the lake bottom to study principally their total, inorganic and organic phosphorus. Related sediment parameters such as particle size, organic carbon, carbonate and iron contents were also studied in detail.

It is shown that the lake sediments are generally a sand-silt-clay mud enriched with carbonate (11.4-42%), organic carbon (0.9-11.4%) and iron (1.6-5.6%).

The total phosphorus content in these sediments is 503-1329 μg/g, inorganic phosphorus, 468-954 μg/g and organic phosphorus, 35-526 μg/g.  相似文献   
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