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71.
Goals, Scope and Background Among other substances, sulphur dioxide (SO2), nitric oxide (NO) and nitrogen dioxide (NO2) are parameters which are routinely measured to describe basic air quality. Organic extracts of airborne particulate matter contain mutagenic chemical compounds of different origins. The aim of the study was to find correlations between routine monitoring data and mutagenic activity of organic extracts of simultaneously drawn samples.Methods Specimens were collected over a period of two years at 8 sampling sites in south-west Germany. Simultaneously, concentrations of NO, NO2, and SO2 were measured on-line within the framework of the official air monitoring network of Baden-Württemberg, Germany. Dust samples were collected for biotesting using high volume air samplers equipped with glass fibre filters. After sampling was completed, filters were extracted and samples were prepared for biological testing. Mutagenic activity was tested by means of the plate incorporation assay (Ames test) using S. typhimurium TA98 and TA100 tester strains. During the first year of the study, all tests have been performed with and without metabolic activation. Additionally, a series of tests has been performed in parallel with TA98 and TA98NR.Results and Discussion Comparison of Ames test data obtained with and without metabolic activation indicates no statistically significant difference between both methods. Therefore, during the second year of the study, all tests have been performed without metabolic activation. Average yearly activities at the sampling sites were between 1 und 27 Revertants per m3 (Rev/m3). High activities were preferably found at congested sites (Karlsruhe, up to 95 Rev/m3). However, peak values of over 100 Rev/m3 were found in other places where pollution by traffic is significantly lower. The reason for these high level values is not evident. Tests performed using TA98NR tester strain indicate a significant share (average 31%) of compounds requiring activation by nitroreductase for mutagenic activity. Average mutagenic activity can be correlated to routine monitoring parameters. Comparison of averaged data for particular sampling sites indicates significant correlation between nitric oxide and mutagenic activity in TA98 (r2=0.90), while correlation between nitrogen dioxide (0.84) or sulphur dioxide (0.52) and mutagenic activity is weaker. For TA100, correlations are generally weaker than for TA98. Comparison of data for mutagenic activity and routine monitoring data of distant sites being sampled simultaneously shows parallel behaviour.Conclusions Results from this study show that mutagenic activity can be compared to seasonal and local variations of gaseous indicator air pollutants. Tester strain TA98 generally shows the best correlations. Although pollution by particle-bound mutagenic substances is significantly higher during the cold season than during summer on average, mutagenic activity of airborne dust is not a continuous effect. During winter, peak levels as well as low pollution periods can occur. Even during winter time mutagenic activity can reach very low levels typical for summertime. Comparison of results for distant sampling sites where samples have been collected simultaneously indicate that “classical” indicators of air pollution and bacterial mutagenicity of organic extracts from airborne particulate matter are influenced by connected effects. Seasonal trend of mutagenic activity, in particular, is similar to the concentrations of nitrogen oxide. NO is a strong indicator for vehicle exhaust gases. It is concluded that the average mutagenic activity at particular sites can be estimated using NO concentrations as an indicator.  相似文献   
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Ziel und Hintergrund

In den bisherigen REACH-Verordnungsentwürfen wird als einer der wichtigen Gründe für die Gesetzes-initiative ‘die Schaffung von Anreizen für die Substitution gefährlicher durch weniger gefährliche Stoffe’ genannt (REACH 2003, 61). Damit wird die Frage aktuell, was denn Unternehmen als Wirtschaftssubjekte ‘anreizen’ oder eben auch ‘nicht anreizen’ kann, gefährliche chemikalien zu substituieren: Welche Marktkräfte wirken bereits positiv, die durch regulative Vorgaben eventuell verstärkt werden können, und welche die Substitution behindernden Marktkräfte sollten durch regulative Maßnahmen abgeschwächt werden?

Schwerpunkte

Die Autoren untersuchen auf Basis ihrer Vorarbeiten und Fallstudien zur Substitution die Rahmenbedingungen — Treiber und blockierende Faktoren — für Substitution. Dabei werden auch aktuelle Positionen zur Substitutionsproblematik einbezogen, so z.B. die Stellungnahme des Ausschusses für Umwelt, Gesundheit und Sicherheit der Royal Society of Chemistry (UK), des UK Chemicals Stakeholder Forums sowie die gegenwärtigen Kompromisse zwischen Europäischem Rat und Europäischem Parlament zur Regelung der Substitution unter REACH.

Ergebnisse und Schlussfolgerungen

Gegenwärtig fördern weder die Marktdynamik noch die Gesetzgebung Substitution effektiv genug. Die Unternehmen selbst sind zögerlich, wenn Kosten und Haftungsfragen sowie Kundenprioritäten der Substitution entgegenstehen. Substitution wird vom Gesetzgeber oft nur als Rahmengebot, als Generalklausel, als Anspruch, als Vorrangstrategie oder als Priorität gefordert. Dennoch gibt es sowohl in der Gesetzgebung als auch in der Marktentwicklung positive Ansätze, die regulativ unterstützt werden können.

Perspektive

Der entscheidende Punkt für die Frage der regulativen Substitutionsvorgaben ist, auf welche Weise der Staat die Marktdynamik durch Setzen von Innovationszielen befördern kann. Der Staat sollte in Kooperation mit den Stakeholdern in technischen Dossiers die bekannten Substitutionsmöglichkeiten und Risikominderungsmaßnahmen zusammen stellen, einen Realisierungszeitpunkt vorgeben, Mindeststandards vorschrieben und auch detaillierte Regulation androhen, falls nichts geschieht. Eine case-to-case-Beurteilungs-Methode ist der Substitutionsproblematik in der Regel angemessen, um den Aufwand und die erforderlichen Maßnahmen annähernd genau zu bestimmen.  相似文献   
76.
The GMS countries, supported by the Asian Development Bank, have adopted a holistic, multidimensional approach to strengthen infrastructural linkages and facilitate cross border trade through (i) the establishment of a trans-boundary road connecting two economic nodes across marginalised areas, followed by 2) facilitation of environmentally and socially sound investments in these newly connected areas as a means to develop livelihoods. The North–South Economic Corridor is currently in its second phase of development, with investment opportunities to be laid out in the NSEC Strategy and Action Plan (SAP). It targets the ecologically and culturally sensitive border area between PR China's Yunnan Province, Northern Lao PDR, and Thailand. A trans-boundary, cross-sectoral Strategic Environmental Assessment was conducted to support the respective governments in assessing potential environmental and social impacts, developing alternatives and mitigation options, and feeding the findings back into the SAP writing process. Given the spatial dimension of corridor development—both with regard to opportunities and risks—particular emphasis was put in the application of spatial modelling tools to help geographically locate and quantify impacts as a means to guide interventions and set priorities.  相似文献   
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The simulated concentrations from a numerical 3-dimensional regional air quality model (MC2AQ) are compared to those of ground-based observations in north-eastern Canada and the United States. The model has oxidant chemistry for both inorganic and organic species and deposition routines driven online by a mesoscale compressible community meteorological model (MC2). A standard emission inventory of anthropogenic, natural and biogenic sources for the year 1990 for 21 atmospheric trace species was used in the simulation. The model was run for July 1999, because of the occurrence of a high ozone episode and the availability of the monitoring data for surface O3, SO2, NO, NO2 and NOx. The comparisons during the episode show that the model performs quite well for predicting concentrations and diurnal variations of the surface ozone. The predictions for other gaseous species show some discrepancies with observations, but they are consistent with the results from other models evaluated in the literature. The uncertainties in the emission inventory for these species might be the main causes of the discrepancies. Further studies are needed to improve the predictability of SO and NOx, especially as the model is developed to include particulate matter formation as a result of these gaseous precursors.  相似文献   
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Several methods were developed to detect the cyclic volatile methylsiloxanes (cVMSs) including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) in water, sediment, soil, biota, and biosolid samples. Analytical techniques employed to optimize measurement of this compound class in various matrices included membrane-assisted solvent extraction in water, liquid–solid extraction for sediment, soil, biota, and biosolid samples. A subsequent analysis of the extract was conducted by large-volume injection–gas chromatography−mass spectrometry (LVI−GC−MS). These methods employed no evaporative techniques to avoid potential losses and contamination of the volatile siloxanes. To compensate for the inability to improve detection limits by concentrating final sample extract volumes we used a LVI–GC–MS. Contamination during analysis was minimized by using a septumless GC configuration to avoid cVMS’s associated with septum bleed. These methods performed well achieving good linearity, low limits of detection, good precision, recovery, and a wide dynamic range. In addition, stability of cVMS in water and sediment was assessed under various storage conditions. D4 and D5 in Type-I (Milli-Q) water stored at 4 °C were stable within 29 d; however, significant depletion of D6 (60–70%) occurred only after 3 d. Whereas cVMS in sewage influent and effluent were stable at 4 °C within 21 d. cVMS in sediment sealed in amber glass jars at −20 °C and in pentane extracts in vials at −15 °C were stable during 1 month under both storage conditions.  相似文献   
80.
ABSTRACT

The city of East St. Louis, IL, has a history of abundant industrial activities including smelters of ferrous and non-ferrous metals, a coal-fired power plant, companies that produce organic and inorganic chemicals, and petroleum refineries. A protocol for soil analysis was developed to produce sufficient information on the extent of heavy metal contamination in East St. Louis soils. Soil cores representing every borough of East St. Louis were analyzed for heavy metals—As, Cd, Cu, Cr, Hg, Ni, Pb, Sb, Sn, and Zn. The topsoil contained heavy metal concentrations as high as 12.5 ppm Cd, 14,400 ppm Cu, ppm quantities of Hg, 1860 ppm Pb, 40 ppm Sb, 1130 ppm Sn, and 10,360 ppm Zn. Concentrations of Sb, Cu, and Cd were well correlated with Zn concentrations, suggesting a similar primary industrial source. In a sandy loam soil from a vacated rail depot near the bank of the Mississippi River, the metals were evenly distributed down to a 38-cm depth. The clay soils within a half-mile downwind of the Zn smelter and Cu products company contained elevated Cd (81 ppm), Cu (340 ppm), Pb (700 ppm), and Zn (6000 ppm) and displayed a systematic drop in concentration of these metals with depth. This study demonstrates the often high concentration of heavy metals heterogeneously distributed in the soil and provides baseline data for continuing studies of heavy metal soil leachability.  相似文献   
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