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The electrical and magnetic properties of single crystals of 1:1 charge-transfer complexes of protonated flavins and phenols have been investigated. The results indicate the following pattern for the electronic behavior of these materials. Charge carriers produced in the dark or by illumination are rapidly trapped and contribute to the electrical conductivity by virtue of thermal release from trapping sites. The photocurrent is composed essentially equally of positive and negative carriers, with a rate limitation imposed by carrier migration. Electron paramagnetic resonance results indicate that complete electron-transfer processes can occur at lattice imperfection sites which are produced either during the crystallization process or by removal of solvent from already formed crystals. The unpaired spins so produced behave as localized, doublet state, free radicals.

Results of a study of broad and narrow optical absorption bands of F‐aggregate color centers in NaF are given in terms of correspondence between optical absorption band and defect model. Comparison is given to previous work. New results or results which modify previous conclusions are reported for F2+, F3+, M′, M, and N centers, as well as for an impurity center which gives rise to a prominent optical absorption band at 312 mμ (300°K). It is proposed that this center consists of an oxygen‐impurity–F‐center complex. A number of identifications were made possible through use of OH− and O−− dopings, which favor centers with net positive and net negative charges, respectively.

Un homogenat brut deTribolium confusum Duval peut hydrolyser les molecules d'ATP, d'ADP, d'AMP et d'α-glycerophosphate. L'activite de l'ATPase depend des ions Mg++ et Ca++. La courbe illustrant les variations de l'activite de cette ATPase en fonction du pH, montre deux pH optima, l'un a 7.5 et l'autre a 8.5. L'activite de l'ATPase est elevee durant la periode larvaire, alors que la croissance est active et elle est faible durant la periode pupale. La concentration de l'ATP est toujours inversement proportionnelle a l'activite de l'ATPase et cela a tous les stades du cycle vital de l'insecte.

HYDROPHOBIC interactions are important in maintaining the conformations of proteins and various macromolecules. The free energies of these interactions are entropic in origin, for the enthalpy changes are actually unfavourable at low temperatures (ΔH>0). It is generally believed that around the nonpolar parts of the solutes in contact with water there is an increased ordering1–3 of the water molecules as a result of hydrogen bonding, and that on the formation of the hydrophobic bond this order is diminished so that there is a positive entropy change. We have recently shown4 that there are solvophobic interactions in ethylene glycol, a polar nonaqueous solvent, chiefly on the grounds of the formation of micelles by several cationic detergents and the limited solubility of hydrocarbons in this solvent.