Amines such as those obtained by the hydrolysis of many common pesticides generally react rapidly and quantitatively with either 4-chloro-a,a,a-trifluoro-3,5-dinitrotoíuene or a,a,a,4-tetrafluoro-3-nitrotoluene in alkaline solution to produce substituted anilines. These derivatives readily undergo gas chromatography and may be detected quantitatively A rather large proportion of the pesticides now in common use contain the amine function or may be readily converted to amines. This characteristic is true whether the chemicals in question are employed as insecticides, herbicides, fungicides, or in other ways (Table I). Hydrolysis, under either acidic or basic conditions, is the most common method for conversion.Hydrolysis followed by quantitative determination of the generated amine has been widely employed in both
Fertilization and early development in the horse were studied by recovering oviductal ova at various times after postovulatory mating. Ova collected between 7 and 22 h post coitum (pc) were examined for evidence of fertilizing sperm, cellular changes accompanying fertilization, and pronuclear development. Five ova collected between 7 and 9 h pc contained a marginal metaphase plate, but had no indication of sperm components; three of these, however, showed reduced numbers of cortical granules. Two activated ova (10 and 14 h pc) were in telophase of the second meiotic division, following incorporation of the fertilizing sperm. The fertilizing sperm was situated in a slight elevation; the nucleus was expanding but lacked a nuclear envelope. The pronuclear stage in the horse began as early as 12 h pc, and lasted at least until 21 h pc. Sperm tail remnants were seen in 5 of 7 pronuclear-stage ova, although the crowding of the cytoplasm with clusters of lipid and vacuoles made discerning sperm tail remnants difficult. The spindles of the metaphase stage of the second meiotic division were oriented radially, that is, at right angles to the cell surface, in all but one ovum, so this orientation is not a response to fertilization.
cause of consumption of nitrous acid by compounds other than the primary aromatic amine. The highly colored Nnitroso and C-nitroso compounds formed with secondary and tertiary amines similarly might interfere with colorimetric methods. Simple gas chromatography would be unsuitable for nonvolatile amines. Yet, only the diazonium salt liberates nitrogen upon mild pyrolysis, thus providing a specific measure of primary aromatic amine content.Analysis of nitrite in nitrate required special modification of the diazotization conditions. Anthranilic acid was chosen for diazotization because its diazonium salt has good water solubility. Hydrochloric acid was unsuitable for reaction in the presence of high concentrations of nitrate because of the potential formation of aqua regia. Since a strong acid was required to achieve rapid, quantitative diazotization, trifluoroacetic acid was substituted. Trifluoroacetic acid is completely dissociated in aqueous solution and is readily removed upon vacuum drying. It was necessary to run reactions in dilute solution rather than platinum boats to prevent small, but significant losses of nitrous acid by volatilization. The results of analysis of synthetic nitrite-nitrate mixtures are given in Table III.
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