We have been making measurements of the rate of reactions of Oz(blC:) in a discharge flow system. The mechanisms and kinetics of the reactions involving this species have been outlined by Ogryzlo and co-workers.'*2 The 'C: state is continuously being formed in the tube by the disproportionation of two lowerlying Oz(alA,) molecules:The (IX;) is quenched either on the wall or by an added quencher:Our principal measurement is the relative intensity of the forbidden emission of the I Z : state at 7,619 A. The '2: concentration (and emission intensity) is usually that calculated from Reactions 1 through 3 using the steady-state approximation.A conventional Stern-Volmer plot of intensity as a function of quencher pressure yields only a ratio, ka/kw. The problem is to determine kw accurately so that kQ can be obtained. The decay of 7,619 A intensity along the length of the flow tube is characteristic of the decay of the 'A, source in this steady-state situation. A previous determination' of kw has necessitated a knowledge of ko and absolute intensity measurements. We have developed a new direct method for measuring kw in these systems. The technique involves placing a wire spiral in the flow (FIGURE la). With proper choice of size and material (silver plated on platinum or aluminum) the wire will preferentially quench the 'C: state more than it quenches the 'A: state. This quenching disrupts the steady-state nature of the 'Xi kinetics at one point in the tube. Below the spiral the 'C: concentration grows back into a new steady-state value (see FiGURE 1 b). The rate of this relaxation is characteristic of, and can be used to calculate, kw. From the analysis of this type of data, a value of the surface deactivation efficiency for Pyrex@ glass of about 0.02 has been obtained. This value is close to that observed by Izod and Wayne.3 This kw combined with Stern-Volmer data has yielded a kQ for H 2 0 of 4 X lo-'' cc sec-', which is intermediate between values of 20 x lo-'* reported by Sthul and Welge4* and 1 x obtained by Ogryzlo's group.' Bimolecular quenching rates can also be obtained directly with the wire spiral. In the presence of an added quencher the relaxation period is shorter, being characterized by a pseudo first-order rate constant k = (kw + ka[Q]). The slope of a plot of this rate constant versus [Q] is kQ. We get values of kQ by this method that agree with the Stern-Volmer data.

A B S T R A C T The interaction of the testis and gonadotropin secretion was studied in 15 men surviving chemotherapy for lymphoma. Azoospermia and complete destruction of all testicular germinal elements were present in 10 of the 15 men; however, Sertoli cells and Leydig cells were present. In these 10 men plasma follicle-stimulating hormone (FSH) levels were fourfold higher than in normal men of similar age whereas luteinizing hormone (LH) levels were normal. In contrast, both FSH and LH were normal in the remaining five men. Three had a full complement of spermatogenic tissue on biopsy and normal sperm concentrations. The other two men were azoospermic; one demonstrated full spermatogenesis in 30% of his tubules; the other had only a few spermatogonia in all tubules. In those patients with lower levels of gonadotropins pituitary insufficiency was excluded by the demonstration of appropriate responsiveness of FSH and LH to clomiphene administration. Similarly, Leydig cell function was normal since plasma testosterone was within the normal range in 13 of the 15 men and only slightly decreased in two. Thus, following chemotherapy, testicular damage was restricted to the germinal tissue, and this in turn was associated with a selective increase in FSH. The source of the FSH inhibitor is either the Sertoli cell or early germinal elements. However, since FSH levels are only half as high as those reported for castrate men, other testicular factors may modify FSH secretion.

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A relaxation method is developed which permits a direct measurement of O2(b1Σg+) quenching rate constants. An Al wire spiral is used to selectively quench O2(1Σ) which is normally present in discharged oxygen as a steady-state intermediate. The characteristic time for the reestablishment of the O2(1Σ) steady state is used to determine wall and bimolecular quenching rates. With this method, absolute rate constants are obtained from relative intensity measurements of the O2(1Σ) emission at 7619 Å. The rate constant for quenching by H2O is found to be 4.0 ± 0.6 × 10−12 cc sec−1. Rate constants for a number of other quenchers are reported.