Kinetics of the precipitation of palladium dimethylglyoximate from homogeneous solution.
The kinetics of formation of palladium dimethylglyoximate in the post-nucleation and pre-nucleation stages, and the effect of palladium on the reaction of biacetyl and hydroxylamine, have been studied.
The oximation of biacetyl
Abstract Spectrophotometric evidence indicates that the reaction of biacetyl with hydroxylamine proceeds through the formation of two carbinolamine intermediates. The second of these intermediates is also encountered in the reaction of biacetyl monoxime with hydroxylamine. The rate-limiting step in the oximation of biacetyl is the slow dehydration of the initially formed intermediate, as is evidenced from the various rate constants obtained for the two reactions over the range 0–10°. When niekel(II) is present in the biacetyl-hydroxylamine system, the formation of nickel dimethylglyoximate proceeds by two independent mechanisms, whereas only a single mechanism is responsible for precipitate formation in the biacetyl monoxime-hydroxylamine system.
Effects of diet on urine composition of cats with calcium oxalate urolithiasis.
Ten client-owned cats with calcium oxalate (CaOx) urolithiasis were evaluated to determine the effect of diet on urine CaOx saturation. Two dietary treatments were evaluated in each cat: the diet consumed just prior to urolith detection and a canned diet formulated to prevent CaOx uroliths. This study revealed that hypercalciuria is a consistent abnormality in cats with CaOx urolith formation. When urolith-forming cats consumed a diet formulated to prevent urolith formation, activity product ratios for CaOx (which estimate the degree to which urine is saturated with CaOx) were significantly lower. These results suggest that consumption of an appropriately formulated urolith-prevention diet will reduce recurrence of CaOx urolithiasis.