Estimation of the Ultraviolet-C Doses from Mercury Lamps and Light-Emitting Diodes Required to Disinfect Surfaces.

Disinfection of surfaces by ultraviolet-C (UV-C) radiation is gaining importance in diverse applications. However, there is generally no accepted computational procedure to determine the minimum irradiation times and UV-C doses required for reliable and secure disinfection of surfaces. UV-C dose distributions must be comparable for devices presently on the market and future ones, as well as for the diverse surfaces of objects to be disinfected.

Trends in particle matter and its elemental composition in Santiago de Chile, 2011 - 2018.

Daily fine (PM) and coarse (PM) particle matter (PM) samples collected at Parque O'Higgins station in downtown Santiago de Chile have been studied to find the trends in concentration from 1998 to 2018. Elemental concentration was obtained using X-ray fluorescence (XRF). Regression models from previous studies indicate that the PM and PM fractions have had a continuous decrease since 1988 mostly due to several policy control measures carried out over several decades.

Modification in the soil and traffic-related sources of particle matter between 1998 and 2007 in Santiago de Chile.

Santiago de Chile is one of the most polluted South American cities, concentrating its pollution episodes during winter. Daily PM2.5 (particulate matter [PM] < or = 2.

Trends in the elemental composition of fine particulate matter in Santiago, Chile, from 1998 to 2003.

Santiago, Chile, is one of the most polluted cities in South America. As a response, over the past 15 yr, numerous pollution reduction programs have been implemented by the environmental authority, Comisión Nacional del Medio Ambiente. This paper assesses the effectiveness of these interventions by examining the trends of fine particulate matter (PM(2.

Analysis of PM10, PM2.5, and PM2 5-10 concentrations in Santiago, Chile, from 1989 to 2001.

Daily particle samples were collected in Santiago, Chile, at four urban locations from January 1, 1989, through December 31, 2001. Both fine PM with da < 2.5 microm (PM2.

Use of the light absorption coefficient to monitor elemental carbon and PM2.5--example of Santiago de Chile.

The optical absorption coefficient, particulate matter with an aerodynamic diameter <2.5 microm, and elemental carbon (EC) have been measured simultaneously during winter and spring of 2000 in the western part of Santiago, Chile (Pudahuel district). The optical measurements were carried out with a low-cost instrument recently developed at the University of Santiago.