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IntroductionExtraction of pesticide residues from grains and grain products Clean-up of pesticide residue extracts from grains and grain products Gas chromatographic determination of organophosphate, pyrethroid and carbamate insecticides High-performance liquid chromatographic determination of organophosphate, pyrethroid and ca rbamate insecticides Conclusion References

of Contents introduction Recovery procedures for antioxidants Qua ntif icat ion of ant ioxida n ts Colorimetric methods Spectrophotometric methods in the ultraviolet region Paper and thin-layer chromatographic methods Gas chromatographic methods Methods based on high-performance liquid chromatography Miscellaneous techniques

The radiation-induced formation of trapped radicals in cellulose, both in vacuum and air, has been studied by e.p.r, spectroscopy. Factors affecting radical concentration have been examined, including total dose, dose rate, heat, cellulose pretreatment, and kinetics of radical decay. All spectra were asymmetric in shape. Variables affecting line shape have been studied, including oxygen, irradiation conditions such as the presence of water, acetic acid, copper sulphate solution, methanol, ethanol, potassium iodide, and liquid ammonia. The data indicate that the observed cellulose e.p.r, spectrum is composed of an overlapping singlet with a triplet. Studies of radical decay show that a significant concentration of e.p.r. species still remains in irradiated cellulose after 4 years at ambient temperature.

The results of a study of grafting to pre-irradiated cellulose are presented using the monomers styrene, vinyl acetate, and 2- and 4-vinylpyridines. The effect of pre-irradiation dose has been examined over the range 1-10 Mrad in air at dose rates of 0.114-1.16 Mrad/hr. Of a number of additives included in the grafting solutions, small amounts (10-23%) of acridine completely suppressed grafting, anthracene inhibited it, and the halobenzenes produced a sensitization in the reaction.