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The elementary reaction of NH(a1Δ) with the saturated hydrocarbons: was studied for R = CH4, C2H6, C3,H8, and n-C4H10 at room temperature in the gas phase at low pressure (10 < p/mbar ≤ 40). NH(a) was produced by HN3 laser photolysis (λL = 248 nm) and detected by laser induced fluorescence. Time resolution was obtained from the variable delay between the photolysis pulse and the detecting laser pulse. – The rate constants (in cm3/mol s) were found to be: independent of pressure in the above given range. – The product NH2(X) and the quenching pathway (NH(X)) were followed directly and quantitatively by laser induced fluorescence. The quenching pathway was found to be unimportant([NH(X)]α /[NH(a)]0 < 1%) for all alkanes. The fraction of NH2(X) formed, {[NH2(X)]α/[NH(a)]0} decreases with increasing chain length from (CH4) = 1.0; (C2H6) = (0.34 ± 0.06); C3H8 = (0.20 ± 0.02) to n-C4H10 = (0.07 ± 0.02). These ratios did not change with pressure (10 ≤ p/mbar ≤ 40). – The increase in the rate constants for the reactions with H–(CH2)n – H with increasing n (1 ≤ n ≤ 4) and the decrease in the NH2 yield demonstrate that NH2 is not formed by abstraction but by an insertion mechanism.

Lipoxygenasen sind fur die Bewertung der Qualitat von Olen und Olsaaten von groser Bedeutung. Deshalb ist die selektive Bestimmung der Aktivitat verschiedener Isoenzyme mit einfachen analytischen Methoden Gegenstand dieser Arbeit. Es werden Methoden aus der Literatur auf ihre Anwendbarkeit untersucht und optimiert. Am Beispiel der Sojabohnen-Lipoxygenase wird die getrennte Bestimmung der Isoenzyme L-1, L-2 und L-3 mit einer UV-photometrischen Methode vorgestellt. Als Substrat wird bei den Bestimmungen Linolsaure verwendet. Der relative Fehler der Bestimmung betragt fur L-1 und L-2 2%, fur Lipoxygenase L-3 etwa 2,1%.