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711.
略谈清洁生产战略在医院废物处理中的指导意义 总被引:1,自引:0,他引:1
清洁生产战略作为环境管理的一项手段 ,是实现可持续发展战略的一项重要举措。医院废物作为一种危险废物 ,在其处理处置过程中 ,也应引入清洁生产思想 ,这对于有效利用资源和能源 ,减轻环境压力 ,都具有重要意义。 相似文献
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Ibarra-Berastegi G Madariaga I 《Environmental science and pollution research international》2003,10(6):361-367
GOAL. SCOPE. BACKGROUND: In urban environments, the measured levels of ozone are the result of the interaction between emissions of precursors (mainly VOCs and NOx) and meteorological effects. In this work, time series of daily values of ozone, measured at three locations in Bilbao (Spain), have been built. Then, after removing meteorological effects from them, ozone and traffic data have been analyzed jointly. The goal was to identify traffic situations and link them to ozone levels in the area of Bilbao. METHODS: To remove meteorological effects from the selected ozone time series, the technique developed by Rao and Zurbenko was used. This is a widely used technique and, after its application, the fraction obtained from a given ozone time series represents an ozone forming capability attributable to emissions of precursors. This fraction is devoid of any meteorological influence and includes only the apportion of periodicities above 1.7 years. In the case of Bilbao, the ozone fractions obtained at three locations have been compared on that time scale with traffic data from the area. RESULTS AND DISCUSSION: For the 1993-1996 period, a regression analysis of the ozone and traffic fractions due to periodicities above 1.7 years (long-term fractions), shows that traffic is the main explanatory factor for ozone with R2 ranging from 0.916 to 0.996 at the three locations studied. Analysis of these longterm fractions has made it possible to identify two traffic regimes for the whole area, associated to different profiles of ozone forming capability. The first one favors low ozone forming capability, and is associated with a situation of fluent traffic. The second one shows high ozone forming capability and represents congestion. Joint analysis of raw data of ozone and traffic do not show any clear pattern due to the strong masking effects that seasonal-meteorological effects (mainly radiation) have on the measured ozone signal. If only immission data of ozone are available, as in this case, a comparison between ozone and traffic can only be made on the long-term time scale, since that is the only fraction embedded in the ozone time series that can exclusively be attributed to emissions of precursors. This fact stresses the need to study the different fractions embedded in the time series of ozone measured levels separately. CONCLUSION: Though the coefficients obtained in the regression are only valid for the 1993-1996 period, these traffic regimes represent long-term targets (congestion or fluent traffic) that can inspire policies for a joint management of the traffic and pollution by ozone in the area of Bilbao beyond that period. RECOMMENDATIONS AND OUTLOOK: The results of this work show the need of a joint management of ozone and traffic in Bilbao. Since an accurate knowledge of traffic was not available, the use of emission factors to relate traffic and actual ozone levels has not been possible. For this reason, this study has focused on the long-term fractions of traffic and ozone. In the future, if a more accurate knowledge of traffic is available, it will be possible to find relationships between traffic and ozone on all time scales. 相似文献
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介绍了一种电除尘器脉冲供电的基本原理及其在锌沸腾炉电除尘器上的应用试验情况。结果表明,在基本保持同一工况条件下,脉冲供电比直流供电降低出口烟气含尘浓度50.4%~79.6%;脉冲供电能改善电除尘器运行性能,提高电除尘器改善系数达1.32;脉冲供电运行安全可靠。 相似文献
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本文通过对加压溶气过程的分析 ,建立了理想加压溶气过程模型 ,在此基础上推导出新的理论溶气量计算公式 ,并与现有的计算公式进行了比较。 相似文献
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