In concentration of hydrogen peroxide, first, the solution should be quite pure, and then, it concentrate with methods such as vacuum distillation and cooling crystallization, because impurities in the hydrogen peroxide solution in high concentrations are causing decomposition of this substance; that is very dangerous. The purpose of this article is separation of chromium and magne...

The present work is carried out to study the antioxidant potential of ethanolic extract of Alstonia scholaris Linn. ( Apocynaceae ) using various in vitro tests including 1,1-diphenyl-2-picryl-hydrazil (DPPH . ) free radical scavenging, metal ion chelating, hydrogen peroxide scavenging, superoxide anion radical scavenging, and ferric thiocyanate reducing ability.   Ethanolic ex...

The importance of a constant hydrogen ion concentration of the arterial blood to normal tissue function has been greatly stressed within the past decade. The apparent dependency of tissue acidity on blood acidity coupled with the constancy of the arterial hydrogen ion concentration in the normal individual seemed to justify this emphasis. This constancy of hydrogen ion concentration of the arte...

1. It has been shown quantitatively that the degree of response of the hind limbs of tadpoles to the action of thyroxin is dependent upon the lengths of the limbs at the beginning of treatment. 2. Both the potency of the inducing substance and the rate of penetration of the substance into the animal might be involved in the effects of hydrogen ion concentration on induced development. 3. Change...

1. The hydrolysis of gelatin at a constant hydrogen ion concentration follows the course of a monomolecular reaction for about one-third of the reaction. 2. If the hydrogen ion concentration is not kept constant the amount of hydrolysis in certain ranges of acidity is proportional to the square root of the time (Schütz's rule). 3. The velocity of hydrolysis in strongly acid solution (pH less th...

In the title molecular salt, 3C5H12N(+)·HSO4 (-)·SO4 (2-), each cation adopts a chair conformation. In the crystal, the hydrogen sulfate ion is connected to the sulfate ion by a strong O-H⋯O hydrogen bond. The packing also features a number of N-H⋯O hydrogen bonds, which lead to a three-dimensional network structure. The hydrogen sulfate anion accepts four hydrogen bonds from two cations, where...

1. Pepsin in solution at 38 degrees C. is most stable at a hydrogen ion concentration of about 10(-5) (pH 5.0). 2. Increasing the hydrogen ion concentration above pH 5.0 causes a slow increase in the rate of destruction of pepsin. 3. Decreasing the hydrogen ion concentration below pH 5.0 causes a very rapid increase in the rate of destruction of the enzyme. 4. Neither the purity of the enzyme s...