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Present Status of Polonium Tolerance Estimations

Description: From abstract: "This report contains a summary of biological information on distribution, excretion, and toxicity of polonium; a comparison of results obtained when maximum permissible exposure rates for man are calculated from available data by different methods; and a critical evaluation of the present status of Po tolerance estimates."
Date: October 14, 1948
Creator: Hursh, John B. & Stannard, J. Newell
Partner: UNT Libraries Government Documents Department


Description: From foreword: This is a report on the efforts of Monsanto Chemical Co. to solve some of the chemical problems involved in the atomic energy program.
Date: July 1956
Creator: Moyer, Harvey Vernon
Partner: UNT Libraries Government Documents Department


Description: A bibliography of eight general reviews on the chemistry of Po is presented. The characteristics of Po isotopes are tabulated. The oxidation states, compounds, complexes, and analytical chemistry of Po are reviewed. Radiochemical procedures for Po are presented. (D.L.C.)
Date: January 1, 1961
Creator: Figgins, P.E.
Partner: UNT Libraries Government Documents Department

Half-Life of Polonium

Description: Abstract: "The half-life of polonium has been measured by a calorimetric method using samples several thousand times larger than have been previously available. The value is found to be 138.3 +/- 0.1% days."
Date: September 9, 1946
Creator: Beamer, William H. & Easton, William E.
Partner: UNT Libraries Government Documents Department

Dibutyl Carbitol Solvent Extraction of Polonium-210 from Nitric Acid Solutions of Irradiated Bismuth

Description: Abstract: "A continuous countercurrent solvent extraction process utilizing dibutyl carbitol as the extractant has been developed for separating 210Po from large amounts of associated bismuth. Both laboratory and pilot plant data demonstrate the process is a suitable headend step in recovery of kilogram quantities of 210Po. Typically, the extraction process recovers over 98% of the 210Po, essentially free from bismuth (Bi DF>1500), in a dilute HNO3 solution suitable as a starting material for final concentration and purification steps."
Date: February 1968
Creator: Schulz, Wallace W. & Richardson, G. L.
Partner: UNT Libraries Government Documents Department

Description and Vibrational Analysis of the Molecular Spectrum of Polonium

Description: Report issued by the Oak Ridge National Laboratory discussing the vibrational analysis of the molecular spectrum of polonium. Experimental procedures, results, and analysis are presented. This report includes tables, illustrations, and photographs.
Date: January 29, 1957
Creator: Charles, G. W.; Hunt, D. J.; Pish, G. & Timma, D. L.
Partner: UNT Libraries Government Documents Department

Determination of half life of polonium-210 by counting: final report

Description: Introduction: "A number of determination have been made of the half life of polonium-210 by calorimetry. Counting affords an entirely different method of determining half lives and requires only a small amount of activity. Therefore for comparison a half-life determination by counting was undertaken with a sample of approximately 0.5 millicurie of polonium."
Date: June 1, 1951
Creator: Curtis, Mary Lou
Partner: UNT Libraries Government Documents Department

Radiometric Analysis of Thick Samples

Description: Introduction: Measurements of polonium content in solids are usually performed by dissolving the material and preparing a thin sample which can be measured with one of the available instruments. A measurement of the radiation emerging from the thick sample should be sufficient to evaluate the polonium content. For this reason a calculation has been performed and the results have been compared with those obtained by the thin sample method. Obviously this proposed method using thick samples would be faster.
Date: March 1, 1944
Creator: DeBenedetti, Sergio
Partner: UNT Libraries Government Documents Department

Gamma scale chemistry progress report, May 1--31, 1948

Description: An attempt has been made to prepare a compound of postum (Polonium 210) analogous to K{sub 2}{sup TeBr}{sub 6}. A preliminary experiment indicates possible preparation of bromides of postum and that these bromides are analogous to the chloride of postum. Photomicrographs of two crystalline forms of a product resulting from the reaction of bromine and postum are included in this report together with procedure used to form these crystals. Intermediate compounds formed in the attempted preparation of potassium postum bromide include a white residue from nitric acid containing postum and a yellow material formed on the ignition of this white residue. This yellow residue was identical in appearance to the yellow dioxide of postum. A red crystalline precipitate resulted when the yellow residue, which may well be QO{sub 2}, was treated with solution of hydrobromic acid and potassium bromide. Investigation of the use of titanium trichloride as a reducing agent to titrate, quantitatively tellurium dioxide has not yielded concordant results. An effort is being made to determine the best conditions for such a titration potentiometrically. Variations in concentrations, temperature of titration, electrode surface, acid concentration, and degree of agitation are in suspect.
Date: December 31, 1948
Creator: Martin, A.
Partner: UNT Libraries Government Documents Department

The solution chemistry of polonium (Ad Interim Report)

Description: This document is a March 1949 Ad Interim Report from the Mound Laboratory on the solution chemistry of polonium. A consideration of the valences of the elements of the Group VI-A would indicate that the oxidation states of -2, 2, 4, and 6 might be expected for polonium. From the decrease in stability of the hydrides of these elements with increase in atomic number, one would expect that the compound H{sub 2} Po would be very unstable and that the oxidation state of -2 would not occur in solution. Furthermore, the stability of the oxidation state +6 as well as the stability of the highest oxidation state of a given element decreases as the atomic number increases in Group VI-A and Period VI respectively. For these reasons, the oxidation state +6 for polonium would be expected to occur only in a strongly oxidizing medium. The +4 state would be expected to be stable. The work discussed herein indicates that polonium exists as PoO{sup ++} in a nonoxidizing or reducing medium.
Date: March 22, 1949
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

Report for General Research April 1 to August 7, 1950 (Polonium Volume)

Description: Research on polonium chemistry and physics is being continued on a reduced scale. Those problems which have direct bearing on the preparation of the metal and those which will lead to a better understanding of any phenomenon encountered are being continued. Data from the calorimetric measurements of polonium on Calorimeters 39 and 46 were treated by the method of least squares to give a grand mean half life of polonium equal to 138.3993 {+-} 0.0093 days (1-13). New apparatus has been constructed for the measurement of the vapor pressure of polonium and its compounds in the low and the high temperature ranges. Technical difficulties have delayed the actual collection of data (1-22). The constant current magnet to be used for the measurement of the Hall effect of polonium has been tested and found satisfactory. A device utilizing nuclear magnetic resonance absorption for determining field strength has been constructed on a preliminary basis (1-24). A total of 208 lines in the ultraviolet region between 3200 A and 1900 A have been measured with an error of less than {+-}0.02 A (1-28). Studies on the X-ray and spark spectra of polonium and its compounds have been conducted. A preliminary study by X-ray analysis has shown an equilibrium state of polonium between 65{sup o} and 100{sup o}. No sharp change of alpha polonium to the beta form has been noted below 100{sup o} (1-49). Previous evidence of a third phase of polonium at liquid air temperatures could not be duplicated (1-53). Confirmation of previous measurements of the coefficient of expansion of polonium with a more accurate temperature control has been achieved. A study of a platinum polonide sample has been carried out (1-55). Measurements of the Hall coefficient of polonium is being delayed until the pole caps for the completed magnet are obtained ...
Date: September 11, 1950
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

Polonium purification

Description: Three processes for the purification of {sup 210}Po from irradiated bismuth targets are described. Safety equipment includes shielded hotcells for the initial separation from other activation products, gloveboxes for handling the volatile and highly toxic materials, and provisions for ventilation. All chemical separations must be performed under vacuum or in inerted systems. Two of the processes require large amounts of electricity; the third requires vessels made from exotic materials.
Date: September 1, 1996
Creator: Baker, J.D.
Partner: UNT Libraries Government Documents Department

Physics group progress report, May 1--31, 1948

Description: Various studies conducted at Mound Laboratory concerning physical properties of postum (Polonium 210) are described. Some studies are entitled Purity of Postum (Vacuum Balance Method); Vapor Pressure of Postum; X-ray Studies; Vapor Pressure by Effusion; Molecular Weigh of Postum; and Weighing Procedures for Macroassay.
Date: December 31, 1948
Creator: Knauss, H.P.
Partner: UNT Libraries Government Documents Department

Density of metallic polonium

Description: Determinations of the density and coefficient of thermal expansions of postum (Polonium 210) were attempted on 20 curies of polonium as obtained from production foils.
Date: May 18, 1948
Creator: Brody, B.
Partner: UNT Libraries Government Documents Department