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151.
We report on ambient atmospheric aerosols present at sea during the Atlantic–Mediterranean voyage of Oceanic II (The Scholar Ship) in spring 2008. A record was obtained of hourly PM10, PM2.5, and PM1 particle size fraction concentrations and 24-h filter samples for chemical analysis which allowed for comparison between levels of crustal particles, sea spray, total carbon, and secondary inorganic aerosols. On-board monitoring was continuous from the equatorial Atlantic to the Straits of Gibraltar, across the Mediterranean to Istanbul, and back via Lisbon to the English Channel. Initially clean air in the open Atlantic registered PM10 levels <10 μg m?3 but became progressively polluted by increasingly coarse PM as the ship approached land. Away from major port cities, the main sources of atmospheric contamination identified were dust intrusions from North Africa (NAF), smoke plumes from biomass burning in sub-Saharan Africa and Russia, industrial sulphate clouds and other regional pollution sources transported from Europe, sea spray during rough seas, and plumes emanating from islands. Under dry NAF intrusions PM10 daily mean levels averaged 40–60 μg m?3 (30–40 μg m?3 PM2.5; c. 20 μg m?3 PM1), peaking briefly to >120 μg m?3 (hourly mean) when the ship passed through curtains of higher dust concentrations amassed at the frontal edge of the dust cloud. PM1/PM10 ratios ranged from very low during desert dust intrusions (0.3–0.4) to very high during anthropogenic pollution plume events (0.8–1).  相似文献   
152.

Background, aim, and scope

According to the high incidence of cancer worldwide, the amount of cytostatic drugs administered to patients has increased. These compounds are excreted to wastewaters, and therefore become potential water contaminants. At this stage, very little is known on the presence and elimination of cytostatic compounds in wastewater treatment plants (WWTP). The aim of this study was to develop a liquid chromatography?Chigh-resolution mass spectrometry (LC?COrbitrap?CMS) method for the determination of cyclophosphamide and epirubicin in wastewaters. These compounds represent two outmost used cytostatic agents.

Materials and methods

Extraction and analytical conditions were optimized for cyclophosphamide and epirubicin in wastewater. Both solid-phase extraction using Oasis 200?mg hydrophilic?Clipophilic balanced (HLB) cartridges and direct injection analysis were evaluated. Mass spectral characterization and fragmentation conditions were optimized at 50,000 resolving power (full width at half maximum, m/z 200) to obtain maximum sensitivity and identification performance. Quality parameters (recoveries, limits of detection, and repetitivity) of the methods developed were determined, and best performance was obtained with direct water analysis of the centrifuged wastewater. Finally, this method was applied to determine the presence of cyclophosphamide and epirubicin in wastewaters from a hospital effluent, an urban effluent, and influents and effluents from three WWTP.

Results and discussion

Cyclophosphamide and epirubicin were recovered after 50?mL preconcentration on solid-phase extraction 200?mg Oasis HLB cartridges (87% and 37%, respectively), and no breakthrough was observed by extracting 500?mL of water. Limits of detection were of 0.35 and 2.77?ng/L for cyclophosphamide and epirubicin, respectively. On the other hand, direct injection of water spiked at 1???g/L provided recoveries of 107% for cyclophosphamide and 44% for epirubicin and limits of detection from 3.1 to 85?ng?L?1, respectively. The analysis of wastewaters using direct injection analysis revealed the presence of cyclophosphamide and epirubicin in WWTP influents and hospital and urban effluents at levels ranging from 5.73 to 24.8???g?L?1.

Conclusions

The results obtained in this study demonstrate the capability of LC?COrbitrap?CMS for accurate trace analysis of these very polar contaminants. This method permitted to identify cyclophosphamide and epirubicin in wastewaters and influents of WWTP, but no traces were detected in WWTP effluents. The methodology herein developed is sensitive and robust and applicable for screening of a large number of samples since no preconcentration is needed.  相似文献   
153.
Abstract

Sources and concentrations of indoor nitrogen dioxide (NO2) were examined in Barcelona, Spain, during 1996– 1999. A total of 340 dwellings of infants participating in a hospital-based cohort study were selected from different areas of the city. Passive filter badges were used for indoor NO2 measurement over 7–30 days. Dwelling inhabitants completed a questionnaire on housing characteristics and smoking habits. Data on outdoor NO2 concentrations were available for the entire period of the study in the areas of the city where indoor concentrations were determined. Bivariate analysis was performed to investigate relationships between indoor NO2 concentrations on one hand and outdoor NO2 concentrations, housing, and occupant characteristics on the other. Stepwise multiple linear regression was performed with variables that were 1996 and 27.02 ppb in 1999, with the highest yearly value of 27.82 ppb in 1997. In the same time period, mean outdoor NO2 concentration ranged between 25.26 and 25.78 ppb with a peak of 30.5 ppb in 1998. Multiple regression analysis showed that principal sources of indoor NO2 concentrations were the use of a gas cooker, the absence of an extractor fan when cooking, and cigarette smoking. The absence of central heating was also associated with higher NO2 concentrations. Finally, each ppb increase in outdoor NO2 was associated with a 1% increase in indoor concentrations.  相似文献   
154.
Treatment of municipal solid waste (MSW) landfill leachate generally results in low percentages of nutrient removal due to the high concentration and accumulation of refractory compounds. For this reason, individual physical, chemical and biological processes have been used for the treatment of raw landfill leachate and sometimes for the mixture of domestic wastewater and landfill leachate. In this work, the possibility of treating landfill leachate was tested in a bench-scale pilot plant by a two-step method combining adsorption and coagulation-flocculation. Zeolite synthesized from coal fly ash, a by-product of coal-fired power stations, was used in this study both as a decantation aid reagent and as an adsorbent of COD and NH4-N. The coagulation-flocculation step was performed by the use of aluminium sulphate and a polyelectrolyte (ACTIPOL A-401). The leachate was collected directly from a storage unit of the organic fraction of MSW, before it was composted. For this reason the raw leachate was diluted before treatment. The sludge was recirculated to enhance the removal efficiency of nutrients as well as to optimize flocculant saving and to decrease sludge production. The results showed that it is possible to remove 43%, 53% and 82% of COD, NH4-N, and suspended solids, respectively. Therefore, this method may be an alternative for ammonium removal, as well as a suitable pre- or post-treatment step, in combination with other processes in order to meet regulatory limits.  相似文献   
155.
Six years (1998–2003) of measurements of ambient air concentrations of total suspended particulate (TSP) measured at a rural background monitoring station in Tenerife (Canary Islands), the El Río station (ER, 28°08′35″N, 16°39′20″W, 500 m a.s.l.) were studied. African dust outbreaks were objectively identified using a new quantitative tool, called the African Index. This index indicates the percentage of time that an air mass remained over an African region at one of three possible height intervals of the lower troposphere. After identifying these episodes, a study of the background TSP levels at the ER station and of direct and indirect (those which cause vertical deposition of dust) African air mass intrusion impacts was performed. Taking into account both direct and indirect episodes, a total of 322 days of African dust intrusion were objectively identified (a mean of 54 episodes per year) in the period 1998–2003, some of them caused by “transition episodes” or “return African air masses”. A subjective method confirmed that 256 of these days were caused by direct impacts of African dust on the ER station. A mean TSP value of 21.6 μg m−3 was found at the station during this period. All the episodes occurred when the TSP concentration was >28.5 μg m−3. The TSP background (14 μg m−3) can be assumed to be representative of the MBL of the Eastern North Atlantic subtropical region. The highest number of dust gravitational settlement (or indirect) episodes occurs in summer, but the highest contribution of these episodes to the TSP levels is in March with a monthly mean TSP contribution of up to 30.5 μg m−3.  相似文献   
156.
Safe amendment rates (the predicted no-effect concentration or PNEC) of seven organic wastes were estimated from the species sensitivity distribution of a battery of soil biota tests and compared with different realistic amendment scenarios (different predicted environmental concentrations or PEC). None of the wastes was expected to exert noxious effects on soil biota if applied according either to the usual maximum amendment rates in Europe or phosphorus demands of crops (below 2 tonnes DM ha−1). However, some of the wastes might be problematic if applied according to nitrogen demands of crops (above 2 tonnes DM ha−1). Ammonium content and organic matter stability of the studied wastes are the most influential determinants of the maximum amendment rates derived in this study, but not pollutant burden. This finding indicates the need to stabilize wastes prior to their reuse in soils in order to avoid short-term impacts on soil communities.  相似文献   
157.
Development of methodologies to assess the safety of reusing polluted organic wastes in soil is a priority in Europe. In this study, and coupled with chemical analysis, seven organic wastes were subjected to different aquatic and soil bioassays. Tests were carried out with solid-phase waste and three different waste eluates (water, methanol, and dichloromethane).Solid-phase assays were indicated as the most suitable for waste testing not only in terms of relevance for real situations, but also because toxicity in eluates was generally not representative of the chronic effects in solid-phase.No general correlations were found between toxicity and waste pollutant burden, neither in solid-phase nor in eluate assays, showing the inability of chemical methods to predict the ecotoxicological risks of wastes. On the contrary, several physicochemical parameters reflecting the degree of low organic matter stability in wastes were the main contributors to the acute toxicity seen in collembolans and daphnids.  相似文献   
158.
Mineral dust is an important aerosol species in the Earth’s atmosphere and has a major source within North Africa, of which the Sahara forms the major part. Aerosol Time of Flight Mass Spectrometry (ATOFMS) is first used to determine the mixing state of dust particles collected from the land surface in the Saharan region, showing low abundance of species such as nitrate and sulphate internally mixed with the dust mineral matrix. These data are then compared with the ATOFMS single particle mass spectra of Saharan dust particles detected in the marine atmosphere in the vicinity of the Cape Verde islands, which are further compared with those from particles with longer atmospheric residence sampled at a coastal station at Mace Head, Ireland. Saharan dust particles collected near the Cape Verde Islands showed increased internally mixed nitrate but no sulphate, whilst Saharan dust particles collected on the coast of Ireland showed a very high degree of internally mixed secondary species including nitrate, sulphate and methanesulphonate. This uptake of secondary species will change the pH and hygroscopic properties of the aerosol dust and thus can influence the budgets of other reactive gases, as well as influencing the radiative properties of the particles and the availability of metals for dissolution.  相似文献   
159.
The relationship between specific particulate emission control and ambient levels of some PM10 components (Zn, As, Pb, Cs, Tl) was evaluated. To this end, the industrial area of Castellón (Eastern Spain) was selected, where around 40% of the EU glazed ceramic tiles and a high proportion of EU ceramic frits are produced. The PM10 emissions from the ceramic processes were calculated over the period 2000–2006, taking into account the degree of implementation of corrective measures throughout the study period. Abatement systems were implemented in the majority of the fusion kilns for frit manufacture in the area as a result of the application of the Directive 1996/61/EC, leading to a marked decrease in PM10 emissions. By contrast, emissions from tile manufacture remained relatively constant because of the few changes in the implementation of corrective measures. On the other hand, ambient PM10 levels and composition measurements were carried out from 2002 to 2006. A high correlation between PM10 emissions from frit manufacture and ambient levels of Zn, As, Pb and Cs (R2 from 0.61 to 0.98) was observed. On the basis of these results, the potential impact of the implementation of corrective measures to reduce emissions from tile manufacture was quantified, resulting in a possible decrease of 3–5 μg/m3 and 2 μg/m3 in ambient mineral PM10 (on an annual basis) in urban and suburban areas, respectively. This relatively simple methodology allows us to estimate the direct effect of a reduction in primary particulate emissions on ambient levels of key particulate components, and to make a preliminary quantification of the possibilities of air quality improvement by means of further emission reduction. Therefore, it is a useful tool for developing future air quality plans in the study area and in other industrialised areas.  相似文献   
160.
Agricultural intensification, at local and landscape scales, has caused a decrease in plant diversity and changes in species composition in cereal fields. To better understand the role of landscape complexity and farming systems in shaping plant assemblages, it is of interest to focus on functional traits rather than on floristic composition, which may help to highlight trends in vegetation patterns. We analysed the relative abundance of various functional attributes (different life forms, growth forms, wind-pollinated species and wind-dispersed species) at three contrasted field positions (boundary, edge and centre) of 29 organic and 29 conventional cereal fields distributed in 15 agrarian localities of NE Spain. Agricultural intensification affected the biological attributes of the vegetation in dryland Mediterranean cereal fields; local factors (farming system and position) had a more prominent role in affecting plant functional composition than the surrounding landscape. Local factors were important for life form distribution, growth form and pollination type, whereas landscape complexity mainly affected the proportion of wind-dispersed species. Therefore, depending on the objective of the study, it is important to select functional attributes sensitive to the different scales of agricultural intensification, especially because landscape complexity and land-use intensity are commonly related.  相似文献   
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