GibiaiinahiPrrrs II. @6°RD) TECHNICAL COMMAND INTERIM REPORTS. (TCIR) BEST AVAILABLE COPY TCIR - 507 - SYNTHESIS OF RADIOACTIVE METHYL iopmpE, 1131LABELED. Jess W. Thomas, Phyllis Beamer, and E. Harry ‘Bouton, 1 March 1950. UNCLASSIFIED ” (v) A method is presented for the synthesis of radioactive methyl iodide, to be used later in tests of Standard Canisters V, VII, and VIII. The synthesis was conducted using inert sodium iodide dissolved in a radio- active socéium iodide solution, and inert dimethyl sulfate. The radioactive methyl iodide product of two runs was diluted with inert methyl iodide to provide concentrations of radioactive material suitable for further investigation. These end products were essentially chemically pure, and the radiometric efficiency, or ratio of radioactive product to radioactive input, was determined as 92% and 84%, respectively, for the two runs. TOIR - 508 - DETERMINATION OF RADIOACTIVE METHYL IODIDE (1131) in arr. Jess W. Thomas, E. Harry Bouton, Phyllis Beamer, Eugene E. Grassel, and Elmer H. Engquist, 1 March 1950. CONFIDENTIAL . “he purpose of this study was to develop quantitative methods for the determination of radioactive methyl iodide in air, the ultimate objective being the standardization of test methods for gas mask sorbents. It was first establishe= that an acetate-bromine absorber satisfactorily removes inert methyl iodide from a gas-air stream. It was then determined iodometrically, that the eZficiency of the absorber, is not a function of the gas concentra- tion, at least within the 0.02% to 12.5% limits of these tests. Complementary studies were made using radioactive methyl iodide prepared as described in TCIR 507. Aqueous sodium acetate was added to the absorbed methyl iodide, and the racioiodine precipitated as silver iodide, a nonvolatile material suitable fcr counting. Zt was concluded that additional study of the preparation of radioactive samples is necessary to obtain satisfactory, reproducible results. TCIR - 514 - ACCURACY OF COUNTING RADIOACTIVE BETA EMITTERS USING ENDWINDOW GEIGER TUBES. Jesse W. Thomas, 6 March 1950. UNCLASSTFIED ' (U) To permit the confident use of statistical laws applicable to a counting assay of radioactive material, it is necessary to establish the fact that the statistical laws apply under actual operating conditions. quit SVNRC7 g