Adsorptive stripping voltammetric behaviour of copper complexes of some heterocyclic azo compounds.

Controlled adsorptive accumulation of copper complexed with TAN, TAC, TAR and TAM (heterocyclic azo-compounds) on a static mercury drop electrode provides the basis for the direct stripping measurement of this element in the nanomolar concentration level. The ligand TAN exhibited great sensitivity and better separation of the peak current of the ligand in relation to the complex. The reduction current of adsorbed complex ions of copper is measured by linear scan cathodic stripping voltammetry, preceded by a period of accumulation of a few minutes.

An AIDS prevention program for homeless youth.

Larkin Street Youth Center (LSYC) is a multidisciplinary service center for homeless youth in San Francisco. This article describes the strategies developed by the medical clinic at LSYC for the prevention of human immunodeficiency virus infection.

Flavonoids and alkaloids from Strychnos pseudoquina.

From the leaves of Strychnos pseudoquina (Loganiaceae), isorhamnetin (1) and a new biflavone (2) named strychnobiflavone were isolated together with the alkaloids diaboline and 11-methoxydiaboline.