Temperature dependence of the Kerr effect of hydrogen sulphide

The Kerr effect fo gaseous hydrogen sulphide was measured from 254–341 K and (1.5–16.7) ×10⁵ Pa. The difference between the polarizability in the direction of the molecular dipole and the mean is (?0.029 ± 0.008) × 10^?40 C² m² J^?1. With literature data, this yields all three principal polarizabilities. The first hyperpolarizability β^K is obtained.     

The pzc of mercury in the presence of humic acids and their complexes with aluminium

Variation of the lifetime of a mercury drop with potential was used to determine the pzc of mercury in the presence of soil humic acids and their aluminium complexes. In all cases there was an overall net shift in the pzc in the cathodic direction. Variation in the extent of the shift with pH and concentration indicated greater adsorption of negatively charged species. The shift was smaller in the presence of aluminium humates, probably due to a decrease in the negative charge of the humic acid molecules after complexing. The use of electroanalytical techniques for metal speciation studies in soils and natural water, if humic materials are known to be present, might therefore be limited.