Aerosols containing aliphatic hydrocarbons play a substantial role in the urban atmosphere. Cyclic alkanes constitute a large fraction of aliphatic hydrocarbon emissions originating from incomplete combustion of diesel fuel and motor oil. In the present study, cholestane (C27H48) is used as a model system to examine the OH-initiated heterogeneous oxidation pathways of cyclic alkanes in a photoc...

The up-scaling of an earlier described VUV-photochemical oxidative functionalization of polystyrene aerosols depends primarily on the possibility to increase substantially the particle concentration in the gas phase, the aerosol flux and the rate of oxidation. The VUV-photolysis of tetrachloro-methane (CCl4) in the presence of air was chosen for the initiation of the oxidation of the polystyren...

A measurement campaign (IMBALANCE) conducted in 2009 was aimed at characterizing the physical and chemical properties of freshly emitted and photochemically aged combustion particles emitted from a log wood burner and diesel vehicles: a EURO3 Opel Astra with a diesel oxidation catalyst (DOC) but no particle filter and a EURO2 Volkswagen Transporter TDI Syncro without emission aftertreatment. Ic...

Optimization of electric energy consumption in degradation of Indigo Carmine based on a new cylindrical batch suspension photocatalytic reactor designing concerning the main engineering parameters such as mixing, reaction kinetic, mass transfer, catalyst illumination, and inherent potential of contaminant was done. The most degradation efficiency was observed within in air flow rate 1.2L. min-1...

The paper by Geeraert et al. sets out to determine the degradation processes of OC in the Tana River (Kenya), focusing on microbial decomposition. Microbial degradation of DOC was measured in dark incubation experiments, eliminating loss of DOC through photochemical oxidation. It was concluded that bacterial mineralization of labile DOM was significant, contrary to the findings of other studies...

In this paper, Chen et al. use kinetic analysis of OH p-HBA formation in illuminated snow samples to infer OH photochemical formation rates and steady-state concentrations in (assumed) pristine snow taken from Arctic regions. This work is important and timely: in a rapidly changing and increasingly human-impacted Arctic environment, understanding the contributions to local atmospheric reactivit...

The observed mass-independent sulfur isotopic composition (Delta33S) of volcanic sulfate from the Agung (March 1963) and Pinatubo (June 1991) eruptions recorded in the Antarctic snow provides a mechanism for documenting stratospheric events. The sign of Delta33S changes over time from an initial positive component to a negative value. Delta33S is created during photochemical oxidation of sulfur...

An improved microprocedure for the determination of tocopherol in blood serum is reported. Tocopherol is oxidized by ferric chloride and the pink complex of ferrous ions with 4,7-diphenyl10,10-phenanthroline (bathophenanthroline) is determined spectrophotometrically. The test is more sensitive than colorimetric methods using 2,2’,2” -tripyridine,2,2’-bipyridine (bipyridyl) or 2,4,6tripyridyl-s-...

This paper reports for the first time the luminescent property of polystyrene (PS), produced by pulsed ultra violet laser irradiation. We have discovered that, in air, ultra-violet (UV) irradiated PS nanospheres emit bright white light with the dominant peak at 510 nm, while in vacuum they emit in the near-blue region. From the comparison of PS nanospheres irradiated in vacuum and air, we sugge...