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271.
The primary objective of this study was to determine the presence of unregulated organic chemicals in reclaimed water using complementary targeted and broad spectrum approaches. Eleven of 12 targeted human pharmaceuticals, antioxidants, and plasticizers, and 27 tentatively identified non-target organic chemicals, were present in secondary effluent entering tertiary treatment trains at a wastewater treatment plant and two water reclamation facilities. The removal of these compounds by three different tertiary treatment trains was investigated: coagulant-assisted granular media filtration (California Title-22 water, 22 CCR 60301-60357; Barclay [2006]), lime clarification/reverse osmosis (lime/ RO), and microfiltration-reverse osmosis (MF/RO). Carbamazepine, clofibric acid, gemfibrozil, ibuprofen, p-toluenesulfonamide, caffeine, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and N-butyl benzenesulfonamide (N-BBSA) were present at low to high nanogram-per-liter levels in Title 22 water. The lime/RO product waters contained lower concentrations of clofibric acid, ibuprofen, caffeine, BHA, and N-BBSA (<10 to 71 ng/L) than their Title 22 counterparts. The MF/RO treatment reduced concentrations to levels below their detection limits, although BHT was present in MF/RO product water from one facility. The presence of the target analytes in two surface waters used as raw drinking water sources and a recharged groundwater was also examined. Surface waters used as raw drinking water sources contained caffeine, BHA, BHT, and N-BBSA, while recharged groundwater contained BHT, BHA, and N-BBSA. Nontarget compounds in recharged groundwater appeared to be attenuated with increased residence time in the aquifer.  相似文献   
272.
Researchers have applied open path optical sensing techniques to a variety of workplace and environmental monitoring problems. Usually these data are reported in terms of a path-average (or path-integrated) concentration. When assessing potential human exposures along a beam path, this path-average value is not always informative, since concentrations along the path can vary substantially from the beam average. The focus of this research is to arrive at a method for estimating the upper-bound in contaminant concentrations over a fixed open beam path. The approach taken here uses a statistical model to estimate an upper-bound concentration based on a combination of the path-average and a measure of the spatial variability computed from point samples along the beam path. Results of computer simulations and experimental testing in a controlled ventilation chamber indicate that the model produced conservative estimates for the maximum concentration along the beam path. This approach may have many applications for open path monitoring in workplaces or wherever maximum concentrations are a concern.  相似文献   
273.
The bacterium, Xenorhabdus nematophila, is a virulent insect pathogen. Part of its pathogenicity is due to impairing cellular immunity by blocking biosynthesis of eicosanoids, the major recognized signal transduction system in insect cellular immunity. X. nematophila inhibits the first step in eicosanoid biosynthesis, phospholipase A2 (PLA2). Here we report that the bacterium inhibits PLA2 from two insect immune tissues, hemocytes and fat body, as well as PLA2s selected to represent a wide range of organisms, including prokaryotes, insects, reptiles, and mammals. Our finding on a bacterial inhibitor of PLA2 activity contributes new insight into the chemical ecology of microbe–host interactions, which usually involve actions rather than inhibitors of PLA2s.  相似文献   
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The expansion of the industrial economy and the increase of population in Northeast Asian countries have caused much interestin climate monitoring related to global warming. However, new techniques and better platforms for the measurement of globalwarming and regional databases are still old-fashioned and arenot being developed sufficiently. With respect to this agenda,since 1993, at the request of the World Meteorological Organization (WMO), to monitor functions of global warming, theKorea Meteorological Administration (KMA) has set up a Global Atmospheric Watch (GAW) Station on the western coast of Korea(Anmyun-do) and has been actively monitoring global warming overNortheast Asia. In addition, atmospheric carbon dioxide (CO2) has been measured for a similar KMA global warmingprogram at Kosan, Cheju Island since 1990. Aerosol and radiationhave also been measured at both sites as well as in Seoul. Theobservations have been analyzed using diagnostics of climate change in Northeast Asia and also have been internationally compared. Results indicate that greenhouse gases are in good statistic agreement with the NOAA/Climate Monitoring and Diagnostics Laboratory (CMDL) long-term trends of monthly meanconcentrations and seasonal cycles. Atmospheric particulatematter has also been analyzed for particular Asian types interms of optical depth, number concentration and size distribution.  相似文献   
276.
Objective: Road traffic injuries (RTIs) are a major global health issue causing a global burden of mortality and morbidity. Half of all fatalities on the world’s roads are vulnerable road users (VRUs). The targeted intervention strategies based on fatality analysis focusing on VRUs can effectively contribute to reducing RTIs. This study aimed to compare VRUs and motor vehicle occupants (MVOs) in terms of epidemiology and injury profile.

Methods: We utilized a nationwide, prospective database of RTI-related mortality cases for patients who visited 23 emergency departments between January 2011 and December 2015. All fatalities due to RTIs in the prehospital phase or in-hospital were eligible, excluding patients with unknown mode of transport and those admitted to general wards. The primary and secondary outcomes were fracture injuries and visceral injuries diagnosed using the International Classification of Diseases, Tenth Revision (ICD-10). We compared fracture injuries between VRUs and MVOs using Abbreviated Injury Scale (AIS) 2? and 2+ classification.

Results: Among a total 3,694 road traffic fatalities (RTFs), 43.3% were pedestrians, followed by MVOs (27.0%), motorcyclists (18.9), bicyclists (6.6%), and agricultural vehicle users (4.2%). The elderly (>60 years old) accounted for 54.9% of VRU fatalities. RTFs occurred most frequently in the autumn and the VRU group and the MVO group showed significant differences in weekly and diurnal variation in RTFs. The injury severities (AIS 2+) of the head, neck, and thorax were significantly different between the 2 groups (P?Conclusions: Elderly pedestrians should be targeted for decreases in RTFs, and road traffic safety interventions for VRUs should be made based on the analysis of temporal epidemiology and injury profiles of RTFs.  相似文献   
277.
Journal of Material Cycles and Waste Management - The purpose of this study was to investigate biogas productivity of algal residues from bioethanol production. Pre-treatment based on enzyme was...  相似文献   
278.
As the generation of waste home appliances increases continuously with economic growth, the importance of recycling becomes more apparent. Many home appliances we use today are recyclable, and recyclable materials from the waste home appliances can be used to create new or refurbishing products. To do that, first of all, we have to know and consider the recyclable materials' recycling potential with environmental and economic information. In this study, an evaluation method to assess recycling potential considering both the environmental and economic factors was suggested for the materials recovered from waste home appliances. Life cycle assessment (LCA) method was applied to obtain the environmental score (SEnv) and an actual value and a static economic model was used to obtain the economic score (SEco). The recycling potential for recyclable materials was calculated by using the SEnv and SEco along with weighting factors derived from an analytical hierarchy process (AHP) method. With the calculated data and evaluation method for the recycling materials, this study could provide useful information for decision makers and product designers in the design for environment (DfE).  相似文献   
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A waste product generated in the sugar industry in India has been converted into a cheap potential adsorbent. This has been characterised and utilized for the removal of chromium (VI) from synthetic and actual wastewater. The sorption efficiency decreases with increase in pH. Adsorption of Cr (VI) on bagasse fly ash follows the Freundlich and Langmuir isotherms and these have been used to obtain the thermodynamic parameters of the process. The sorption capacity of this adsorbent for chromium removal is found to be comparable to other low cost adsorbents.  相似文献   
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