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251.
Goal and Scope
The constant increase of traffic and the rising energy and material consumption both in industry and trade as well as in private households mean a constant challenge to environmental protection and to the air pollution control. With the commencement of the Federal ambient pollution control act in April 1974, the legal basis for the monitoring of air pollution was created. In future, the limit values laid down in the Council Directive 1999/30/EG, 2000/69/EG and 96/62/EG, will be valid. In town and regional planning there is a great demand for a simple index to evaluate the air quality. From the available data of PM10, NO2, O3, CO, SO2, trends of the air quality will be derived.Methods
The indices LQI and TLQ suggested by Mayer et al. (2002) were calculated for selected stations of the air pollution monitoring network (ZIMEN) in Rhineland-Palatine. All analysis are based on hourly recorded value, Mean values and frequency distributions are used for the interpretation. Furthermore, the characteristics and trends of the indices under different weather conditions were examined and discussed.Results
The examination figures out that the air pollutions indices at all stations show similar patterns in the period between January 2001 and December 2002. Neither the LQI, nor the TLQ shows an annual variation. Existing variations are mainly controlled by the general weather situation and the air temperature. High values of the indices appear at extremely high or low mean daily air temperature. The absolute value of the air pollution index is determined by local pollution factors.Outlook and Recommendations
Both indices are well suitable to evaluate the air quality and to assess the effects of state-aided measures for air pollutant control. Therefore, the indices TLQ and LQI should be published as an additional information in the world wide web. 相似文献252.
David M. DeMarini Virginia S. Houk Alfred Kornel Charles J. Rogers 《Chemosphere》1992,24(12):1713-1720
We evaluated the genotoxicity of dichloromethane (DCM) extracts of PCB-contaminated soil before and after the soil had been treated by a base-catalyzed dechlorination process. The treatment process involves heating a mixture of the soil, polyethylene glycol (or hydrocarbons with boiling points of 310–387°C), and sodium hydroxide to 250–350°C. Dechlorination reduced by >99% the PCB concentration of the soil, which was initially 2,200 ppm. The DCM extracts of both control and treated soils were not mutagenic in strain TA100 of Salmonella, but they were mutagenic in strain TA98. Based on results in strain TA98, the base-catalyzed dechlorination process reduced the mutagenic potency of the soil by approximately one-half. The DCM extracts of the soils before and after treatment were equally genotoxic in a prophage-induction assay in
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, which detects some chlorinated organic carcinogens that are not detected by the Salmonella mutagenicity assay. These results suggest that treatment of PCB-contaminated soil by base-catalyzed dechlorination reduced the mutagenicity of the soil slightly. 相似文献
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Alfred Stock 《Die Naturwissenschaften》1937,25(26-27):417-420
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