The decarboxylation of malic acid by <i>Lactobacillus arabinosus</i>

Abstract

A simple but efficient filter for transmitting the short- wave ultraviolet light from a mercury arc lamp may be made from two 25 ml. fused silica round-bottomed flasks (Vitreosil T/A4/407). One contains the cobalt- nickel solution (CoSO4. 7H20 100 g. + NiSO4. 7H20 350 g./l.) and is placed with its centre about 7-5 cm. from the mercury lamp and acts as a lens, forming an image of the lamp about 7-5-8 cm. on the other side. It is stopped down to about 30 mm. diameter by two diaphragms which may be cut in a sheet of metal which is then bent into a U-shape, and the flask pushed in so that the holes grip it. The second flask, which has a glass stopper ground in, is filled with dry chlorine gas. The stopper is greased with vaseline and may with advantage be made hollow so that it can hold some anhydrous calcium chloride held in place with a little glass wool. This flask is so placed that the image of the lamp is formed in its centre, in which position the light passes through