No abstract

The magnetic circular dichroism of the absorption ( M C O ~) of Vi: in GH-silicon carbide shows a strong temperature dependence. Within a crystal field approach the MCOA and g-factors of the hexagonal site defect could be explained, whereas the situation is more complicated for both quasi-cubic site defects owing to a dynamical Jahn-Teller effect.

No abstract

No abstract

Arsenite ion, as arsenic trichloride was extracted into benzene from strongly acidified tissue homogenates. Following this, arsenite was extracted from the benzene into water, made up in 1N HCl and analyzed polarographically. Arsenate ion, left in the homogenate after arsenite extraction is isolated in exactly the same way following treatment of the homogenate with cuprous ion to reduce arsenate to arsenite ion. Treatment of the acidified homogenate with cuprous ion prior to extraction gives a homogenate which is readily analyzed for total "inorganic" arsenic. The method was efficient to a maximum level of about 20 mug inorganic arsenic since at higher levels lower recoveries were found. Analysis of a variety of marine biological specimens, with levels of total arsenic up to 40.5 ppm, indicated little of this arsenic was present in an inorganic form. Post mortem reduction of arsenate to arsenite was found to occur rapidly in fish tissue.