Oils, microbial attack

Another major use for semi-rigid polyurethane foams is as shoe soles. In this application, their light weight, abrasion resistance, and shock absorbing properties are important. In safety shoes, chemical and oil resistance are important. Polyether-based foams are used in applications where microbial attack is common, such as shoes intended primarily for use on soil or grass. 

Shennan, I. L., Microbial Attack on Sulphur-Containing Hydrocarbons Implications for the Biodesulfurization of Oils and Coals../. Chem.Tech. Biotechnol., 1996. 67 p. 109. 

The biomarker molecules are particularly resistant to microbial attack, and thus the ratio of other hydrocarbon components to the biomarker will decrease as the crude oil is biodegraded (Wang et al., 1994). In the case of an ongoing oil discharge into the soil, this ratio will be highest nearest the source and will decrease with increasing distance from the source. Thus, the ratio may be used to locate the source of the contaminant (Whittaker et al., 1995). 

Magno et al. [65] reported an amperometric biosensor for fructose using an electrode prepared by dispersion of MWCNT within mineral oil (60/40 % w/w) and covered by a polymer obtained from the electropolimerization of dihydroxybenzaldehyde. The fructose dehydrogenase was immobilized on different membranes placed on the top of CNTPEs and then covered with an additional polycarbonate membrane (0.03 pm pore size) to prevent fouling and microbial attack. 

Hydrocarbon compounds such as fuels, lubricating oils and creosote contain toxic components. Naphthalene and its methyl-substituted derivatives are some of the most acutely toxic, water-soluble components of crude oils. As the molecular size of hydrocarbons increases, their lipophilicty, environmental persistence and mutagenicity also increase. Many chemicals represent classes of molecules not previously investigated, some have no close structural analogs in nature, and there are those that were intentionally developed to be resistant to microbial attack and to persist in nature. 

Such subtle average profile changes could also establish specific points of microbial attack and help design microbial cleanup schemes for oil spills. 

Thermoplastic elastomers (TPE) and thermoplastic rubbers (TPR) show a varying level of susceptibility to microbial attack. The oils and other additives present in these materials can provide a food source to the... 

Although non-ionic surfactants are often chosen for emulsified systems because of their relatively low toxicity, several problems in formulation have arisen with their use. Most emulsions of edible fats and oils must be preserved against microbial attack. The most effective preservatives have often been the p-hydroxybenzoic acids. Unfortunately, these acids are inactivated by interaction... 

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