Degradation Photolysis

DHS can significantly affect the environmental behavior of hydrophobic organic compounds and lower the possibility of direct contact of such organic compounds with various solid phases. The rate of chemical degradation, photolysis, volatilization, transfer to sediments/soils, and biological uptake may be different for the fraction of organic pollutant that is bound to DHS. If this is the case, the distribution and total mass of a pollutant in an ecosystem depends, in part, on the extent of humic matter-hydrophobic binding. 

Paints and varnishes for use on exteriors of buildings must be protected from the effects of solar radiation which accelerate their degradation (photolysis and photochemical reactions). Given that M = 500 gmol-1 emax = 15 0001 mol 1 cm"1 for Amax - 350 nm, what must be the concentration (expressed in g 1 1) of a UV additive M such that 90% of the radiation is absorbed by a coating of thickness 0.3 mm ... 

The ability of humic substances to bind hydrophobic organics can affect not only their mobility, by decreasing the sorption to sediments, but also the rate of chemical degradation, photolysis, volatilization, and biological uptake of these organics. This interaction can serve to lengthen the lifetimes and transport distances of these contaminants in the environment. 

Long-term storage in an approved landfill, concrete bunker, or abandoned mine. In-place treatment proposals have included biodegradation, chemical degradation, photolysis, and chemical stabilization. 

---