UV treatments

Some physical techniques can be classified into flame treatments, corona treatments, cold plasma treatments, ultraviolet (UV) treatment, laser treatments, x-ray treatments, electron-beam treatments, ion-beam treatments, and metallization and sputtering, in which corona, plasma, and laser treatments are the most commonly used methods to modify silicone polymers. In the presence of oxygen, high-energy-photon treatment induces the formation of radical sites at surfaces these sites then react with atmospheric oxygen forming oxygenated functions. 

Several environment-friendly surface preparation for the treatment of mbber soles with radiations have been recently studied. These treatments are clean (no chemicals or reactions by-products are produced) and fast, and furthermore online bonding at shoe factory can be produced, so the future trend in surface modification of substrates in shoe industry will be likely directed to the industrial application of those treatments. Corona discharge, low-pressure RF gas plasma, and ultraviolet (UV) treatments have been successfully used at laboratory scale to improve the adhesion of several sole materials in shoe industry. Recently, surface modification of SBR and TR by UV radiation has been industrially demonstrated in shoe industry... 

Treatment of TR with UV radiation has been shown to be successful in increasing its adhesion to polyurethane adhesive. A low-pressure mercury vapor lamp (main emission at 254 nm power = 20 mW/cm ) has been used. The UV treatment of TR improves the wettabUity, produces the formation of C—O, C=0, and COO moieties, and ablation is also produced. The extended UV treatment produces greater surface modifications, as well as the incorporation of nitrogen moieties at the surface. Peel strength values increase after UV treatment of TR, in a greater extent by increasing the treatment time. 

Romero-Sanchez M.D., Pastor-Bias M.M., Martfn-Martfnez J.M., and Walzak M.J., 2003, UV treatment of synthetic styrene-butadiene-styrene rubber, J. Adhes. Sci. Technol., 17(1), 25-46. 

Reinemann, D. J., Gouws, P., Cilliers, T., Houck, K., and Bishop, J. R. (2006). New methods for UV treatment of milk for improved food safety and product quality. ASABE Paper Number 066088. ASABE. 

The final product containers must also be pre-sterilized. This may be achieved by autoclaving or passage through special equipment that subjects the vials to a hot WFI rinse, followed by sterilizing dry heat and UV treatment. 

At metamorphosis there was equal mortality in both UV treatments, consequently the UV treatments were pooled within SPMD treatments to increase statistical power when analyzing the deformity data. When analyzed independently of SPMD treatment, no significant deformities were found to occur due to the effects of UV (p > 0.05). SPMD extracts from the site exhibiting amphibian... 

Gluing is difficult, needing pre-treatments such as, for example, chemical etching (sulfo-chromic acid etching), flame oxidation or hot-air (500°C) treatment, corona discharge, plasma or UV treatments. The exposure must be brief and superficial and the original and aged properties must be tested. 

UV treatment exposure to high-intensity UV light promotes chain scissions, cross-linking and reactive site formation. It is particularly used for polyethylene. 

As an alternative to the addition of oxidants, ultraviolet (UV) treatment may be used. UV treatment has found to be less elfective than chlorine or ozone in preventing biofouling, however unlike those methods, it does not incur additional downstream processing (Committee on Advancing Desalination Technology, National Research Council 2008 Cotmvo 2005). This eliminates the need for the use sodium bisulphite or other reducing agents and the potential for FRC or ozone to be present in the final concentrate. 

Modified PTFE surfaces show a high degree of biocompatibility with good cell adhesion and proliferation [7-11], However, the UV-treatment results also in a loss of mechanical stability due to the scission of polymer chains, especially for light-sources with wavelengths below 193 nm [6], Similarly to the ion implantation or plasma modification, also the UV light-irradiation is performed on both sides of a polymer foils in order to avoid the material torsion. 

Oxidative processes can be based on ozonation, UV treatment, hydrogen peroxide, and Fenton s reagent for the destruction of the chromopore [96-107]. 

Fig. 5 SEM images of P. aeruginosa cells sited in Xi02-coated polymer films (A) absence of light (B) after 30 min (1 kJ m ) UV-treatment. Lysed cells are in a box while cell debris are marked with arrows.

ATP (Nova Scotia) conventional STP with preliminary treatment, settling and finally UV treatment ... 

Polyacetylenes are toxic to a broad range of organisms (39) but are especially toxic to insects. At 0.5 ppm, 9 of 14 compounds tested were toxic to first instar mosquito larvae (Aedes aegypti) in 30 min treatments with sources of near UV (15 W/m ) (40). The compounds were more active in sunlight. For example CX-T killed second instar larvae Instantaneously at 4 ppm. Compounds VTI, Ct-T and PHT were especially active and were selected for further testing in dose response experiments (41). For similar near UV treatments, the LC50 for a-T was 19 ppb,... 

Paillard et al. (1988) summarized that 02/UV treatment is not suitable for the removal of aliphatic organohalogen compounds because less energy was required to remove them using air stripping. They found that an energy consumption of about 290-380 Wh m" 3 was required for 90 % removal for unsaturated organohalogen compounds, whereby no optimization was done and could reduce these numbers. 

The simplest example of an enzymic repair process is that of photoreactivation. This phenomenon was rediscovered in 1949 by Kelner, who found that UV-irradiated spores of Streptomyces showed higher survival if exposed to white light after the UV treatment (Kelner, 1949). At the time, this was not interpreted as an enzymic repair process but it was so. Enzymic action became demonstrable when it was shown that it could occur in vitro if, for example, transforming DNA of Haemophilus influenzae was incubated with cell-free extracts of yeast or E. coli after UV-treatment and then exposed to 400 nm light. (Rupert, 1958 1960). This assay made it possible to purify the enzyme from a variety of sources (e.g., Sutherland, 1974 Rupert, 1975). Once an assay for thymine dimers became available, it was shown that the action of the enzyme was to restore the dimers to monomeric thymidine in situ. 

Versari A, Parpinello GP, Tronielli GB, Ferrarini R, Giulivo C. 2001 Stilbene compounds and stilbene synthase expression during ripening, wilting and UV treatment in grape cv. Corvina. J Agric Food Chem 49 5531-5536. 

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