Use Of Sodium Sulfite Research Articles

Vitamin C microscopic demonstration and Golgi apparatus

Sodium thiosulphale may operate directly upon the silver nitrate adsorbed by various cellular and tissular structures, giving rise to a black precipitate of silver sulphide. This precipitate would give rise to a technical artefact, appearing as something added to the genuine picture given by the direct reduction of silver nitrate by the vitamin. The application of a cytochemical method, involving adequate use of sodium sulphite after the acid silver nitrate and prior to the thiosulphate, prevents the silver sulphide precipitate, and shows: a) that vitamin C appears only in the form of granules, irregularly distributed in the cytoplasm; b) that vitamin C storage inside the Golgi apparatus or mitochondria never occurs; c) that the Golgi-like pictures that may occasionally be observed when using the classical silver method, do most probably represent silver impregnation pictures of the Golgi apparatus. This must not be accepted as an equivalent of the silver nitrate reduction by vitamin C stored in the Golgi apparatus.

Sur la thermogravimétrie des précipités analytiques : Dosage du gallium

With the help of the Chcvcnard thcrmobalancc the authors have determined the minimum temperatures necessary for quantitatively converting the derivatives of gallium into oxide Ga 20 3. Hydroxide by ammonium hydroxide 408° Hydroxide by ammonia 400° Hydroxide by urea 475° Hydroxide by aniline 546° Hydroxide by sulpliitc 813° Hydroxide by tannin 520° Cupfcrron 745° Camphoratc 478° Dibromo-oxinate 817° They do not recommend methods of precipitation as fcrrocyanidc and as oxinatc. Precipi- tation by trombe's method is excellent. C-impliorate .ind dibromo-oxinatc can be weighed anhydrous within tlie specified limits of temperature. Finally, the authors solve, in a new certain manner, the problem of separation of gallium and iron by use of sodium sulphite.