Effect of Ultraviolet Irradiation

Numerous tests are available for following photodegradation by ultraviolet irradiation. Infrared (IR) spectroscopy and measurements of change in the molecular weight (MW) and mechanical and electrical properties have been employed. Convenient tests have been found to be the measurement of flexural endurance for PE and change [Pg.216]

Perfluoroalkoxy ethylene Ethylene chlorotrifluoroethylene Fluorinated ethylene-propylene Silicones [Pg.217]

Cross-linked polyethylene Polyisobutylene Styrene-ethylene-styrene PS [Pg.217]

Phenol formaldehyde Polyamide 6 Polyamide 6,6 Polyamide 6,9 Polyamide 6,10 Polyamide 10 Polyamide 2 Polyamide 12 PTFE [Pg.217]

Ultraviolet light assistance of polymers to weathering is an assessment of the effect of solar UV radiation at ambient temperatures. It is used as an overall assessment of changes in physical and mechanical properties and color. In Table 11.6, an excellent rating indicates excellent resistance to weathering and a poor rating indicates poor resistance to weathering. [Pg.217]

Fig 18 Effect of Ultraviolet Irradiation on Induction Time, 50% Point, and Activation Energy of Colloidal Lead Azide (Ref 153)... [Pg.73]

P.W. Levy, Effects of Ultraviolet Irradiation on the Sensitivity of Colloidal Lead Azide , PATR 3174 (1965) 154) Anon, Phase One... [Pg.96]

The effect of ultraviolet irradiation in air on the wettability of thin films of amorphous polymers has been studied. With poly(vinyl chloride), poly(methyl methacrylate), poly(n-butyl methacrylate), poly (ethylene terephthalate), and polystyrene the changes in contact angles for various liquids with irradiation time are a function of the nature of the polymer. A detailed study of polystyrene by this technique and attenuated total reflectance spectra, both of which are sensitive to changes in the surface layers, indicates that the contact angle method is one of the most sensitive tools for the study of polymer photooxidation in its early stages. The method is useful in following specific processes and in indicating solvents to be used in the separation and isolation of photooxidation products. [Pg.80]

Matsuda Y, Kouzuki K, Tanaka M, Tanigaki J. Photostability of gelatin capsules effect of ultraviolet irradiation on the vapor transmission properties and dissolution rates of indomethacin. Yakugaku Zassi 1979 99(9) 907-913. [Pg.46]

Luduena FP, Synder AL, Lands AM. Effect of ultraviolet irradiation of phenylephrine solutions. J Pharm Pharmacol 1963 15 540-543. [Pg.373]

Anagnostou, E., "Effect of Ultraviolet Irradiation on Selected Plastic Films in Vacuum," (1965), NASA TM X-1124. [Pg.313]

Figure 19. Effect of ultraviolet irradiation on induction time, 50% point, and activation energy of colloidal lead azide [117].

Gensler HL. 1988. Enhancement of chemical carcinogenesis in mice by systemic effects of ultraviolet irradiation. Cancer Res 48 620-623. [Pg.469]

J.R. Hunter, J.H. Taylor, H.G. Moser (1979). Effect of ultraviolet irradiation on eggs and larvae of the northern anchovy, Engraulis mordax, and the Pacific mackerel. Scomber japonicus, during the embryonic stage. Photochem. Photobiol, 29,325-338. [Pg.429]

Finally, it can be concluded that the chemical effects of ultraviolet irradiation of polypropylene, as well as polyethylene, are due to the photolysis of impurities such as hydroperoxides and ketonic groups. [Pg.354]

Gonzalez, M.C., C. Marteau, J. Franchi, and D. Migliore-Samour (2001). Cytochrome P450 4A11 expression in human keratinocytes Effects of ultraviolet irradiation. Br. J. Dermatol. 145, 749-757. [Pg.505]

D-Glucitol was selected for study because the absorbing system is composed entirely of hydroxyl groups and is not complicated by the presence of the proposed acetal chromophore. The chemical effects of ultraviolet irradiation of 5 X 10 M oxygenated solutions were examined, using paper-chromatographic and isotope-dilution methods. Using un-... [Pg.51]

Ultraviolet light induced marked changes in the structure of the foui carbamate insecticides. The primary effect of ultraviolet irradiation was to cleave the esteric bond to form the phenol or heterocyclic enols of the carbamate esters which were further decomposed after prolonged exposure. The photodecomposition rate and the nature of the... [Pg.240]

EFFECT OF ULTRAVIOLET IRRADIATION ON SELECTED PLASTIC FILMS IN VACUUM. [Pg.139]

Larmi E (1989) Systemic effect of ultraviolet irradiation on nonimmunologic immediate contact reactions to benzoic acid and meAyl nicotinate. Acta Dermatol Venereol 69 296-301... [Pg.224]

Roggero JP, Garcia-Parrilla C (1995) Effects of ultraviolet irradiation on resveratrol and changes in resveratrol and various of its derivatives in the skins of ripening grapes. Sci Aliment 15 411 22... [Pg.2607]

Matak KE, Sumner SS, Duncan SE, et al. 2007. Effects of ultraviolet irradiation on chemical and sensory properties of goat milk. J Dairy Sci, 90 3178-3186. [Pg.328]

Beukers, R. and Berends, W, Effects of ultraviolet irradiation on nucleic acid and their components, Biochem. Biophys. Acta, 41, 550,1960 49, 181,1961 Leonard, N.J., Me Credie, R.S., Logne, M.W., and Cundall, R., Synthetic spectroscopic models related to coenzymes and base pairs. XI. SoHd state ultraviolet irradiation of l,l -trimethylenebisthymine and photosensitized irradiation of 1,1 -polymethylenebisthymines, /. Am. Chem. Soc., 95, 2320,1973. [Pg.1993]

The study of photo lyase began with the hrst description of photoreactivation in S. griseus in 1949. Photoreactivation is the reversal of the harmful and mutagenic effects of ultraviolet irradiation by blue-light, and in 1958, the enzyme responsible for this phenomenon, photolyase, was discovered. Photolyase uses blue-light energy to repair the two major UV photoproducts in DNA, cyclobutane pyrimidine dimers... [Pg.2685]

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