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Uekoetter F 《Environmental monitoring and assessment》2005,106(1-3):11-26
The Ringelmann smoke chart was used in the United States to assess smoke emissions in the early twentieth century. In fact, it may have been the most important method for measuring air pollution between the late 1800s and the environmental era. However, the popularity of the Ringelmann chart stood in stark contrast to its lack of precision, which smoke abatement experts recognized and discussed among themselves. However, the critique of the Ringelmann scale rarely left the circle of experts and never jeopardized its use. This article discusses the reasons for this striking phenomenon, pointing out that the Ringelmann chart had strong practical and symbolic advantages: it allowed smoke abatement to be conducted in a public and transparent way. With that, the history of the Ringelmann smoke chart is an instructive model for the social construction of measuring techniques. 相似文献
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Evaluation of heavy metal contamination hazards in nuisance dust particles, in Kurdistan Province, western Iran 总被引:3,自引:0,他引:3
The effects of natural andgeochemical factors depending on heavy metal contamination in nuisance dust particles were evaluated. The nuisance dust particles were sampled using passive deposit gauge method for one year from April2010 to March2011 and the obtained samples were measured for the total contents and the contamination levels of Fe, Mn, Cu and As usinggeo-accumulation index (Igeo ), enrichment factor (EF) and the integrated pollution index (IPI). The results showed that, the contamination levels of Fe and Mn based on Igeo values, were uncontaminated (Igeo < 0) (variations of the Igeo index was from -3.11 to -1.751 for Fe, from -0.630 to -1.925 for Mn), while the values of Cu and As were demonstrated to have moderate contamination based on Igeo values (variations of Igeo index was from -1.125 to 0.848 for Cu, and from -2.002 to 1.249 for As). The analysis of EF also revealed minor to moderate enrichment for Mn (1.215-4.214), minor to moderately severe enrichment for Cu (2.791-6.484), and As (1.370-8.462), respectively. The variation of the IPI index also showed low to moderate level of heavy metal pollution in nuisance dust particulates (0.511-1.829). The analysis of the results also approved that the natural processes andgeochemical variables (the changing meteorological parameters) can significantly affect the availability of heavy metals in nuisance dust particles in Western Iran. 相似文献