The partitioning of semivolatile organic compounds between the gas phase and aerosol particles is an important source of secondary organic aerosol (SOA). Gasparticle partitioning of organic and inorganic species is influenced by the physical state and water content of aerosols, and therefore ambient relative humidity (RH), as well as temperature and organic loading levels. We introduce a novel ...

Following on from the companion study (Johnson et al., 2005a), a photochemical tra-jectory model (PTM) has been used to simulate the chemical composition of organic aerosol for selected events during the 2003 TORCH (Tropospheric Organic Chemistry Experiment) field campaign. The PTM incorporates the speciated emissions of 124 5 non-methane anthropogenic volatile organic compounds (VOC) and three...

In 2000, EU regulations for organic animal production set new guidelines for organic pig feeding requiring that this be based on mainly home-grown organic feedstuffs. Doubts were however raised whether these feeding regimes can maintain good growth performance and carcass quality of pigs. Three experiments were carried out to study different organic feeding regimes in weaned piglets and fatteni...

Following on from the companion study (Johnson et al., 2006), a photochemical trajectory model (PTM) has been used to simulate the chemical composition of organic aerosol for selected events during the 2003 TORCH (Tropospheric Organic Chemistry Experiment) field campaign. The PTM incorporates the speciated emissions of 124 nonmethane anthropogenic volatile organic compounds (VOC) and three repr...

Air quality models that generate the concentrations of semi-volatile and other condensable organic compounds using an explicit reaction mechanism require estimates of the physical and thermodynamic properties of the compounds that affect gas/aerosol partitioning: vapour pressure (as a subcooled liquid), and activity coefficients in the aerosol phase. The model of Griffin, Kleeman and coworkers ...

The techniques of membrane extraction permit the application of classical liquid-liquid extraction (LLE) chemistry to instrumental and automated operation. Various shortcomings of LLE are overcome by membrane extraction techniques as they use none or very little organic solvents, high enrichment factors can be obtained and there are no problems with emulsions. A three phase SLM system (aq/org/a...

Phytoremediation uses living higher plants for the removal and biochemical decomposition of environmental pollutants. In this paper Phase I metabolic pathways in the biotransformation reactions of organic pollutants in plants are reviewed. These reactions result in the introduction of functional groups in the xenobiotic molecule or the exposure of preexisting functional groups and lead to the f...

(S)-Hydroxynitrile lyase from Hevea brasiliensis (HbHnl) (EC 4.1.2.39) catalyzes the reversible synthesis of chiral cyanohydrins from aldehydes or ketones and HCN. The enzymatic formation of (S)-mandelonitrile (MN) from benzaldehyde (BA) and HCN was studied in two-phase systems of buffer and organic solvents (diisopropyl ether, methyl-t-butyl ether) using a Lewis cell to investigate the interac...

[1] Aqueous-phase oxidation (in clouds and aerosols) is a potentially important source of organic aerosol and could explain the atmospheric presence of oxalic acid. Methylglyoxal, a water-soluble product of isoprene, oxidizes further in the aqueous phase to pyruvic acid. Discrepancies in the literature regarding the aqueous-phase oxidation of pyruvic acid create large uncertainties in the inclo...