In a previous study, the efficacy of commercial and prototype impactors for sampling diesel particulate matter (DPM) in coal mines was investigated. Laboratory and field samples were collected on quartz-fiber filters and analyzed for organic and elemental carbon. Coal dust contributed a minimal amount of elemental carbon when commercial cascade impactors and prototype impactors, designed by the...

Cross-polarized magic-angle-spinning NMR (CPMAS-NMR) techniques are assumed to be only semi-quantitative in the assessment of carbon distribution in humic substances or natural organic matter, due to a number of interferences such as spinning side bands (SSB) in spectra, paramagnetic species in samples, and low or remote protonation of aromatic carbons. Fast rotor spin rates or direct polarizat...

The referee noticed that we had handled sites and clusters differently: we normalized clusters before computing the average over the continental US but did not normalize sites before calculating the weekly cycles for clusters. The referee suggested that it would be more consistent if we normalized the individual sites before averaging into the clusters. In response to this comment, we have perf...

this paper presents a systematic study of the surface chemistry, porous texture and adsorptive characteristics of prepared new activated carbon using persian mesquite grain. several techniques and methodologies such as, proximate analysis, n2 adsorption–desorption isotherms, scanning electron microscope (sem), fourier transform infrared spectroscopy(ft-ir), x-ray diffraction (xrd), x-ray photoe...

ICx Technologies is currently fielding a real-time, wearable elemental carbon monitor designed to determine real-time diesel particulate levels in mines. Diesel particulates are composed primarily of elemental and organic carbon and have been found to present a health hazard. Diesel particulate levels can be particularly high in underground mines. The Mine Safety and Health Administration (MSHA...

The elemental abundances of carbon, nitrogen, and oxygen in three carbon stars (TX Psc, V Aql, and BL Ori) are determined from high-resolution infrared spectra in a selfconsistent manner, with the dependence of the atmospheric structure on the chemical composition fully taken into account. For this purpose, we have constructed a grid of line-blanketed model atmospheres using a revised Band Mode...