No abstract

The objective of this paper is to study the efficacy of the extraction and isolation of natural toxic constituents present in some well known tree borne oil seeds for effective utilization in pesticide formulations. Neem seed kernels prior to their extraction for oil were pre-treated in single stage with different solvents, viz., isopropanol, acetone and ethanol, in pure as well as in aqueous forms. The aqueous ethanol (water: ethanol 15: 85 v/v) was also employed for three stage counter-current pre-treatment of neem seed kernels, which gave the best results. Further, development of safer pesticides from natural products has been necessitated due to the fact that synthetic organochlorine and organo phosphorus pesticides have created health hazards to mammals and have polluted the ecosystem.

Ricebran oil has higher percentage of free fatty acids which accounts for its use in various industries. In the present work rice bran fatty acids have been used for maleinization. In rice bran fatty acids maleic anhydride reacts with oleic acid without loss of unsaturation in the acid and formed succinic anhydride type adduct. Hydration of the maleinized product is performed to overcome from a number of technological difficulties such as increase in the product viscosity, abrupt and uncontrollable drop of the acid number and also gelation. Inspite of its high free acid content and dark colour, rice bran oil can be conveniently used in laundry soaps directly, but conversion of oil into distilled fatty acids provides various avenues for value added products. The absence of linolenic acid in rice bran fatty acids has an excellent advantage in providing non-yellowing characteristics. This property of rice bran fatty acids opens avnues for coating industries.

Determination of functional and mechanical properties of metal owning to corrosion caused by moisture, chemicals, temperature and several environmental factors propels the demand for corrosion prevention and acid proof lining in numerous end-use industries. Corrosion preventive coatings are devised to protect structures from degradation caused due to exposure in extreme corrosive environment. By acting as a barrier between the materials and the corrosive environment, corrosion prevention coating or linings function as agents that enhance the life of structures by preventing their wear and tear.

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