Protection against UV radiation

Cover skin with a sunscreen lotion with a skin protection factor (SPF) of at least 15, protecting against UV radiation (both UVA and UVB). 

Sinapoyl esters are phenolic compounds found in members of the Brassicaceae, which includes the model plant Arabidopsis thaliana. The two major sinapoyl esters are sinapoyl malate (3.92) and sinapoyl choline (3.93), which accumulate in leaves and seeds, respectively. Sinapoylmalate plays a role in the protection against UV-radiation (Landry et al., 1995), whereas sinapoyl choline may be used as a storage form of choline in seeds (Shirley and Chappie, 2003). The precursor of these two esters is sinapate (3.35). 

Polyoxymethylenes have a low water absorption (0.6% at 20° C). Copolymers are very stable to long exposure in hot water and their properties remain almost unchanged after 1 year of immersion at 82° C. In order to be protected against UV radiation, suitable additives such as benzophe-none or benzotriazole may be included. 

Vitamin E keeps your skin youthful by protecting against UV-radiation. 

Co-A ester ofp-coumaric acid (Fig. 2.29), as well as via an acetate pathway. Flavonoids are often found as glycosides (i.e. they are complexed with sugars in a similar way to tannins) and appear to offer protection against UV radiation and microbial attack, as well as providing the colour in petals and autumn leaves. 

Aramids have been developed from the need to enhance the chemical stability of polyamides. Because of the stability of aromatic rings, aramids also have higher tensile strength and thermal resistance than aliphatic polyamides. These qualities make aramids popular for use in impact resistance applications. However, aramids - along with PA - have low UV resistance. If used in outdoor applications, they must be heavily coated to protect against UV radiation. 

PVC-coated polyester fabrics are used as the building materials for the majority of membrane constmctions. In certain cases, fabrics and yam reinforcements made of polyester require special protection against UV radiation. Because of the need for lower water and/or dirt absorption at the edge of polyester fabrics, specially treated Tow wick yarns are used to avoid the unwanted wick effect (see Rg. 3.5, ref. Mehler). 

Documented effects A tincture of the plant is used to treat arteriosclerosis in patients with normal blood pressure (Nuraliev 1989). In modem medicine this species is used as an expectorant, diuretic, and antiseptic (Khodzhimatov 1989). Metabolites of isoflavones found in the plant were found to protect against UV radiation-induced inflammation and immunosuppression (Widyarini et al. 2001). Isoflavones found in red clover inhibited COX enzyme activity in certain cancer cell types (Lam et al. 2004). Extracts of red clover and individual flavonoid constituents exhibited estrogenic activity in a variety of in vitro assays (Overk et al. 2005). 

Normally UV comes from the sun. The polymers for outdoor applications here is an example of photovoltaic module, need protection against UV radiation (Figure 6.4). In electrical and electronics applications, not only the sun but also the light can be the source of the UV radiation. For example, the modules in liquid crystal display (LCD) also need to be protected against UV radiation emitted by the back light. The fluorescent light possess specific sharp emission of UV radiation and the materials need protection against it. 

Plastics can be protected against UV radiation in three ways. One possibility is the addition of molecules or pigments, which extensively absorb UV radiation and convert the radiation energy directly into heat energy. The particular effectiveness of fine carbon black has already been discussed. Carbon black not only absorbs UV radiation but also binds free radicals through a number of organic compounds adsorbed on the carbon black surface. Absorbent light-protective substances, such as carbon black, display their full effectiveness only when a certain thickness of the exposed layer is available. 

Studies completed on model color-sensitive beverages further illustrate the effectiveness of low level naphthalate modification in protecting against UV radiation exposure (33). The model beverage consisted of 20 ppm Yellow 5, 1000 ppm citric acid, 200 ppm sodium benzoate, and 100 ppb iron. This model... 

The PUR adhesive bond-line must be protected against UV radiation. This can... 

One purpose of the skin is to assure the protection of the body. It works in different fields physical (protection against impacts, mechanical injuries, and chemicals), light (protecting against UV radiation), and also against electricity, cold, and heat. The keratin layer which encloses the human body is an adaptation which allowed leaving the maritime milieu millions of years ago and allowed existence on dry land. The keratin layer allows maintenance of an internal liquid milieu comparable to the primitive maritime milieu. 

Zinc oxide is widely used in skin creams and talcum powders, and is an ingredient in sunscreen lotions for protection against UV radiation. One of its major applications is in the rubber industry, where it lowers the vulcanization temperature and facilitates faster vulcanization (see Section 16.4). Both ZnO and ZnS are used as white pigments, although for most pmposes Ti02 is superior (see Box 21.3 and Section 28.5). 

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