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Large quantities of water are consumed during the washing of granular aggregates in laboratory tests. In this study, the volume of water used when is designed a hot mix asphalt - HMA was estimated. Besides, the effect of washing the aggregate in different quantities of mass and with two levels of water speed flow was evaluated. An analysis of variance (ANOVA) was performed to verify if the results obtained are significant or statically equal. As a general conclusion, it is reported that water consumption decreases significantly when larger amounts of material are washed at the same time and used to wash the particles, lower flow rates. [ABSTRACT FROM AUTHOR]

This article studies the relationship between atmospheric condition (AC) and human mortality rate associated with coarse particulate matter (PM10) in a high-altitude mega-city (Bogotá-Colombia). Information was collected from three automatic monitoring stations equipped with measuring instruments for PM10, temperature, solar radiation and wind speed. The sampling period lasted six years. The results showed the best possible scenario for the maximum hourly concentrations of PM10 (52.3-135 µg/m3). These events occurred during daytime periods where the predominant AC was between unstable and very unstable. The risk from exposure to PM10 showed that February>March>January were the highest risks. These months showed PM10 concentrations 35.9% higher than those observed during the months of lower risk (August>June>July). A higher mortality rate (+2.0%) was suggested in urban sectors with less atmospheric instability (AI) and predominance of impervious cover compared to sectors with higher AI and predominance of vegetated cover. [ABSTRACT FROM AUTHOR]