The toxicity of polycyclic aromatic hydrocarbons (PHAs) is known to be enhanced by light via photosensitization reactions (production of active oxygen) and photomodification of the chemicals (e.g., oxidation) to more toxic compounds. Anthracene (ANT) toxicity in particular has been found to increase dramatically following photomodification. The objective of this study was to identify the photoo...

1. Exposure of chloroplasts to sonic oscillation in a medium of low osmolarity rapidly inactivated the Hill reaction, photophosphorylation, and photooxidation of ascorbate in the presence of dichlorophenyl-1 , 1 -dimethylurea. Concurrently with this inactivation plastocyanin was liberated from the chloroplasts. The addition of plastocyanin during sonic oscillation prevented net loss of plastocy...

The elemental composition of laboratory chamber secondary organic aerosol (SOA) from glyoxal uptake, α-pinene ozonolysis, isoprene photooxidation, single-ring aromatic photooxidation, and naphthalene photooxidation is evaluated using Aerodyne high-resolution time-of-flight mass spectrometer data. SOA O/C ratios range from 1.13 for glyoxal uptake experiments to 0.30–0.43 for α-pinene ozonolysis....

Isotactic polypropylene/multi-walled carbon nanotube (iPP/MWCNTs) films have been exposed to accelerated weathering in a UV device for increasing times. The effect of UV irradiation on the structural and chemical changes has been investigated. The resistance to accelerated photooxidation of (iPP/MWCNTs) films has been compared to the photooxidation behaviour of unfilled polypropylene films with...

Secondary organic aerosol (SOA), formed in the photooxidation of diesel fuel, biodiesel fuel, and 20% biodiesel fuel/80% diesel fuel mixture, are prepared under high-NOx conditions in the presence and absence of sulfur dioxide (SO2), ammonia (NH3), and relative humidity (RH). The composition of condensed-phase organic compounds in SOA is measured using several complementary techniques including...

The use of Escherichia coli as a model organism for studies on the biochemistry of the action of indole-3-acetic acid has revealed that two products of the photooxidation of this plant hormone, 3.hydroxymethyloxindole and 3-methyleneoxindole, are potent inhibitors of the growth of both microorganisms and higher plants (I). The latter compound was first identified by Hinman, Bauman, and Lang (2)...

The light-induced flow of electrons in the chlorophyll-containing particles of photosynthetic bacteria can result in a phosphorylation of adenosine diphosphate to form adenosine triphosphate (l-4), a photooxidation of added mammalian cytochrome c and oxidation-reduction dyes (5), or a photoreduction of diphosphopyridine nucleotide (6). The photoreduction of diphosphopyridine nucleotide by chrom...

Oxidation of cellular structures is typically an undesirable process that can be a hallmark of certain diseases. On the other hand, photooxidation is a necessary step of photodynamic therapy (PDT), a cancer treatment causing cell death upon light irradiation. Here, the effect of photooxidation on the microscopic viscosity of model lipid bilayers constructed of 1,2-dioleoyl-sn-glycero-3-phosphoc...

The 9,lO-dicyanoanthracene-sensitized photooxidation of 2,3-diphenyl1,4-dioxene in CHICN produces ethylene glycol dibenzoate and small amounts of epoxide. Most of the diester is formed from singlet oxygen via the dioxetane, and only a small amount by electron transfer. The epoxide is a primary electron-transfer product. Various mechanistic possibilites for the electron-transfer process are cons...

This study examined the effect coextruding a clear HDPE cap layer onto HDPE/wood-flour composites has on the discoloration of coextruded composites exposed to accelerated UV tests. Chroma meter, XPS, SEM, and UV vis measurements accounted for the analysis of discoloration and degree of oxidation of both uncapped (control) and coextruded composites before and after UV exposures. Two separate dis...