Complex dielectric constants have been measured at frequencies from below 20 c/s to 5 mc/s over the temperature range −40° to −75°C in glycerol, −45° to −90° in propylene glycol, and −80° to −140° in n-propanol. The results for n-propanol are described by the Debye equation, but the values for the other two require a modified equation corresponding to a broader range of dispersion at higher frequencies. In all three liquids, evidence is found for a second dispersion region at still higher frequencies, which accounts for much of the difference between the radio frequency and optical dielectric constant. The relaxation times are quantitatively described over wide ranges by an empirical rate equation of a form which also fits viscosity data. The significance of the various results is discussed.

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The decomposition temperature of the structure I1 clathrate hydrate of tetrahydrofuran has been followed to pressures above 3 kbars, where the hydrate is found to decompose incongruently in the regions of stability of ices I11 and 11, with no evidence of formation of a denser hydrate. From measurements of liquid solution densities and of volume changes at hydrate decomposition the density of the hydrate was obtained. Comparison with the X-ray lattice dimension indicates that at least 98% of the large cages are occupied, the principal uncertainty being in the lattice parameter. A similar treatment is made of Tammann and Krige's data (23) for chloroform hydrate. Analysis of the results of 18 composition determinations of structure I1 hydrates shows no statistical evidence of departure from the ideal composition of 17 mol of water per mol of hydrate former.La temperature de dCcomposition du clathrate hydrate de structure I1 du tktrahydrofuranne a Ct C suivie jusqu'a des pressions superieures a 3 kbar; il a kt6 trouve que dans ces regions de stabilitk des glaces I11 et I1 l'hydrate se decompose d'une f a~o n aberrante sans preuve de formation d'un hydrate plus dense. A partir des mesures de densite des solutions liquides et des changements de volume a la dCcomposition de I'hydrate, il a Ct C possible d'obtenir la densite de l'hydrate. La comparaison avec la dimension du reseau obtenu par rayons X indique qu'au moins 98% des grandes cages sont occupees, ]'incertitude principale &ant dans le parametre retuculaire. A partir des donnCes de Tamman et Krige une analyse similaire est effectuee pour le chloroforme hydrate. Les analyses des resultats se rapportant a 18 determinations de composition d'hydrates ayant la structure I1 ne montrent aucune preuve statistique d'ecart par rapport la composition idkale de 17 mol d'eau par mole de gCnCrateur d'hydrate. Canadian Journal o f Chemistry, 49, 2691 (1971)Among the diverse molecules now known to therefore most easily distinguished from ice and form "gas hydrates" of von Stackelberg's has been chosen for further study. structures I and I1 (1) are a number of ethers and Tetrahydrofuran hydrate was first reported ketones which are distinguished from the classical by Palmer (10) who found from melting point us. gas-hydrate formers by their solubility in water concentration curves a composition of between and by the possibility of hydrogen bonding with 13 and 16 molecules of water per molecule of the host water molecules bf the clathrate struc-tetrahydrofuran (THF), with a probable formula tures. Ethylene oxide (2, 3) and trimethylene of THF.14H20. Erva (1 1) obtained a congruent oxide (4) form hydrates of type I. Structure I1 melting point of 4.38 "C at an approximate comhydrates are formed by dimethyl ether (I), by position of THF.16H20. Several nugatory irtrimethylene oxide, tetrahydrofuran, 2,5-dihydrofuran, propylene oxide, and 1,3-dioxolane (4, 5) and by acetone (6, 7) and cyclobutanone (5,8). With the exception of the study by Glew and Rath (9) of the variable composition o...

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The effects of androgen withdrawal and replacement were investigated in six hypergonadotrophic and six hypogonadotrophic men with hypogonadism. A double blind cross-over design was used comparing testosterone undecanoate (T.U., Organon International), 160 mg daily by mouth, with placebo. There was a significant effect of T.U. on all measures of sexual interest and behaviour. Sexual interest increased within the first week of T.U. administration, ejaculation usually returning within the second week. Behavioural responses were similar in the hyper- and hypogonadotrophic groups. The rise in plasma testosterone during T.U. administration was modest, not reaching the normal range in several cases. 5 alpha dihydrotestosterone rose more substantially. There was a significant fall in sex hormone binding globulin, a rise in oestradiol and no significant change in gonadotrophin concentrations during T.U. administration.

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