Abstract: A proving system is described wherein there is a cylinder and a moving piston within the cylinder having an indicator rod extending out of the cylinder and a cursor on the rod adapted to move relative to a scale. A jacket surrounds the cylinder to which liquid propane will be circulated in order to equalize the temperature of the prover system prior to proving a meter to be proved. Once the temperature of the prover has been equalized the temperature of the liquid propane by continuously circulating the liquid propane through the jacket, the circulation to the jacket will be shut off and test runs of the liquid propane through the meter can be initiated.

Abstract: A process for the preparation of a fatty acid tagged with radioactive iodine, wherein a brominated or iodized fatty acid is reacted, preferably in the omega position, with radioactive iodide in the dry state or with an aqueous solution of radioactive iodide, in the presence of vehicling iodide, to exchange the bromine or iodine of such fatty acid for radioactive iodine.Application to use as radio-pharmaceutical products for studying cardiac metabolism troubles in human beings by scintigraphy.