Podiatry services at clinics of a local health department

Images

Induced rapid release and uptake of phosphate by microorganisms

Cultures of bacteria and of mixed microorganisms are able to release actively a large proportion of their phosphorus to the medium in a matter of hours when kept under anoxic conditions. Only phosphorus is lost, probably as orthophosphate and apparently mostly from the acid-soluble fraction of the cells. The process, which is completely reversible upon aeration, has a change in rate (for a change of 10 degrees C) of 2 to 2.5.

Vacuum Filtration of Large Volumes in the Laboratory

Laboratory vacuum filtration of large volumes of liquids may be safely, easily, and economically accomplished without the use of pumps and without the necessity for placing receivers under vacuum. In the method described the lowered pressure is generated by the filtrate as it falls down a vertical tube.

Freezing-Out, a Safe Technique for Concentration of Dilute Solutions

The principle of freezing-out has been adapted for the quantitative concentration of small or large volumes of dilute solutions. Mechanical stirring is an essential part of the process. The method should prove of greatest value where volatile or heat-labile substances are to be concentrated and is applicable to solutions in certain organic solvents as well as to aqueous solutions.