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Report for General Research July 10 to October 2, 1950 (Supporting Research Volume)

Description: The efficient prosecution of the research and process development on polonium, radium, actinium, waste disposal, and alpha-neutron sources requires the use of a wide variety of instrumental techniques such as: alpha, beta, gamma, and neutron counters and survey meters; emission, absorption, and mass spectroscopy: x-ray and electron diffraction; microbalances; and calorimeters. The complex and kaleidoscopic aspects of our research program require; (1) The application of standard instruments and techniques to a variety of problems; (2) The development of new techniques for the use of standard instruments; and (3) The development of new or improved Instruments. The sum of the above three categories constitutes the field of supporting research. The amplifier for counting pulses of wide dynamic range which was developed for counting beta particles in the presence of alphas has operated so satisfactorily that it has been decided to attempt to adopt it for neutron counting. Substantial improvement at medium counting rates has already been obtained but results at high counting rates are not as satisfactory. The development of a survey meter for monitoring fast neutrons has been under way for sometime. The attainment of higher efficiency has been attempted by the use of a dual-chambered counter tube. The tube operates with a filling of methane gas at two atmospheres pressure. The achievement of leak-proof seals and highest purity methane has been under investigation as their necessity has been indicated by tests. The development of a scintillation counter for surveying and measuring low levels of alpha activity has been continued. Recent efforts have been directed towards determining the correct voltages to be applied to the photomultiplier tube in order to operate under optimum conditions. Recent tests of the coincidence counter to detect scintillations in water containing alpha-active waste material have indicated the necessity of obtaining photomultiplier tubes with low noise ...
Date: November 6, 1950
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

Report for General Research September 18 to December 11, 1950 (Actinium Volume)

Description: The purpose of the research work presented in this volume is to develop a process for the separation and purification of actinium-227 produced by neutron bombardment of radium-226 and to develop methods by which uniform films of actinium metal may be deposited on metallic surfaces. The design work on the cave structure and mechanical equipment used in the actinium separation is proceeding on schedule. As the mechanical design phase is nearing completion the emphasis is being directed toward processing equipment. The process as well as the mechanical equipment has been adapted from the research work of F. T. Hagemann and the Remote Control Group at Argonne National Laboratory. Consequently, one of the first objectives is to become familiary with the chemistry of the process and the operation of the mechanical equipment. Cold runs have been made on the T.T.A. benzene extraction using lanthanum and barium in place of actinium and radium. No difficulty with the operation was observed. The formation of precipitates was one of the difficulties encountered with the process as the precipitates carry radium. It has been found that metals such as nickel cause these precipitates to form and should, therefore, be avoided in the construction of equipment. it was also found that a T.T.A. solution exposed to 0.5 curie of polonium over a period of days develops a precipitate. Some new mechanical features hav eshown promise. The use of copper-coated glassware which will hold together even though the glass is cracked has made it possible to replace custom-built heaters with standard heating mantles. A new graphite, silicone grease mixture appears to hold up in stopcocks handling benzene and, as a result, may eliminate the necessary of entering the cave for regreasing. Tests on the preparation of dense concrete have given results which meet the shielding requirements for ...
Date: January 15, 1951
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

Report for General Research September 18 to December 11, 1950 (Radium Volume)

Description: The purpose of the research work reported in this volume is the development of a process for the separation and subsequent purification of radium from the K-65 (pitchblende) residue. Except for the accumulation of additional experimental data the process is essentially complete. After a preliminary extraction of about 85% of the lead and 40% of the silica with a 40% sodium hydroxide solution, the residue is treated with a solution containing both sodium hydroxide and sodium carbonate to obtain additional lead removal and partial conversion of the radium and barium sulfates to carbonates. After leaching out the soluble carbonates, the residue containing unconverted sulfates is treated with a sodium carbonate solution at 170{sup o} under pressure. A study of the amount and concentration of sodium carbonate required to obtain a satisfactory conversion of the sulfates has shown that the total sodium carbonate may be reduced by 40% and that smaller volumes of solution may be employed without serious decrease in the efficiency of the conversion. In order to make calculations on the number of steps and tank sizes for the radium-barium separation by fractional precipitation, equations have been developed to calculate this information from the theoretical separation factors determined experimentally. Three methods for carrying out the radium-barium separation by fractional precipitation of chromates have been studied and the separation factors determined. The methods differ in the reagent and temperature employed for the neutralization of the nitric acid solution of the chromates. The separation factor improves with decrease in temperature, and a marked improvement has been found by replacing urea which requires boiling temperatures for hydrolysis with potassium cyanate which hydrolyzes at much lower temperatures.
Date: January 15, 1951
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

A Scanning Electron Microscope Facility for Characterization of Tritium Containing Materials

Description: A scanning electron microscope (SEM) facility for the examination of tritium-containing materials is operational at Mound Laboratory. The SEM is installed with the sample chamber incorporated as an integral part of an inert gas glovebox facility to enable easy handling of radioactive and pyrophoric materials. A standard SEM (ERTEC Model B-1) was modified to meet dimensional, operational, and safety-related requirements. A glovebox was designed and fabricated which permitted access with the gloves to all parts of the SEM sample chamber to facilitate detector and accessory replacement and repairs. A separate console combining the electron optical column and specimen chamber was interfaced to the glovebox by a custom-made, neoprene bellows so that the vibrations normally associated with the blowers and pumps were damped. Photomicrographs of tritiated pyrophoric materials show the usefulness of this facility. Some of the difficulties involved in the investigation of these materials are also discussed.
Date: October 1, 1975
Creator: Downs, G. L. & Tucker, P. A.
Partner: UNT Libraries Government Documents Department

Process for Removing Radioactive Wastes from Liquid Streams

Description: The process is under development at Mound Laboratory to remove radioactive waste (principally plutonium-238) from process water prior to discharge of the water to the Miami river. The contaminated water, as normally received, is at a pH between 6 and 90. Under these conditions, plutonium in all its oxidation states is hydrolyzed; however, the level of the radioactive solids varies from about 50ppm down to about 50 ppb and the plutonium remains in a colloidal or subcolloidal condition. The permissible concentration for discharge to the river is about 50 parts per trillion. Pilot plant test show that 95-99% of the radioactive material is removed by adsorption on diatomaceous earth. The remainder is removed by passage through a bed of either dibasic or tribasic calcium phosphate. Ground phosphate rock is equally effective in removing the radioactive material if the flow rate is controlled to permit sufficient contact time. Parameters for optimizing the process are now under study. Future plans include application of the process to wastes from reactor fuels reprocessing.
Date: October 1, 1972
Creator: Kirby, H. W.; Blane, D. E. & Smolin, R. I.
Partner: UNT Libraries Government Documents Department

Reaction Diffusion in the Silver-Zinc and Silver-Aluminum Systems

Description: Multiphase diffusion was investigated in the silver-zinc and silver-aluminum binary systems using metallographic and electron microprobe techniques. Diffusion couples in the silver-zinc system were prepared by electroplating silver onto coupons of a AgZn alloy (62.2% Ag), and diffusion behavior was studied at 600 and 650 degrees C. Couples in the silver-aluminum system were prepared by electroplating silver onto coupons of a AgAl alloy (87.7% Ag) and diffusion measurements were made between 400-600 degrees C. Significant deviations from equilibrium compositions were observed at the moving interphase boundary in each couple. The nucleation of a non-equilibrium silver-rich phase was observed at the location of the initial interface in many of the couples.
Date: October 1, 1971
Creator: Braun, Japnell D. & Powell, Gordon W.
Partner: UNT Libraries Government Documents Department

Reaction Rates for the Formation of Deuterium Tritide from Deuterium and Tritium

Description: The rates of formation of DT in a mixture of D2 and T2 have been measured as a function of initial T2 concentration, pressure, temperature,and methane concentration in a stainless steel reaction container which had been treated to inhibit protium ingrowth. An attempt has been made to explain the experimental resuts on the basis of ion-molecule chain reactions. Some of the observations are consistent with a gas-phase ion, ground-state molecule reaction, but some of the more interesting observations require more complicated models. The addition of excited state molecules or heterogeneous catalytic effects are possibilities that will need further experiments for confirmation.
Date: April 1, 1985
Creator: McConville, G. T.; Menke, D. A. & Ellefson, R. E.
Partner: UNT Libraries Government Documents Department

Report for General Research August 7 to October 30, 1950

Description: Investigation of the physical and chemical properties of polonium important to its behavior and for the improvement of the quantity and quality produced is being continued. A sample of polonium is approximatelyf 1 x 10{sup 9} disintegrations per minute was counted in a Logac for 250 days in order to determine the half life. A statistical treatment of the results gave a half life of 138.3562 {+-} 0.446 days. Combined with previous calorimetric determinations a new grand mean of 138.3975 {+-} 0.0091 days resulted. The wavelengths of 138 lines appearing in the spark spectrum between 3050A and 3463A (Region 4) have been tentatively assigned to polonium and have a probable error of less than 0.02A. Thirty six lines in Region 6 (4225A to 5675A) tentatively assigned to polonium have a probable error of less than D D6A. A measurement of the resistivity of polonium has given a value of about 95 microohm centimeters, and although the Hall voltage could not be measured with much precision, it was possible to set a maximum value of 0.03 millivolt. These values indicate the polonium is a metallic conductor rather than a semiconductor. A rugged but compact gauge made of stainless steel with a tantalum diaphragm has been constructed to have a good sensitivity for the vapor pressure measurement of polonium tetrachloride. Studies by X-ray methods have shown that platinum nickel, and silver form compounds with polonium under the conditions of preparation, while tantalum, gold stainless steel, and beryllium do not. Bismuth formed an alloy of no definite composition which could be separated into its components at 485{sup o} Silver plonide decomposed at 559{sup o}.
Date: December 4, 1950
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

Report for General Research December 26, 1950 to April 16, 1951 (Supporting Research Volume)

Description: This volume presents the quarterly results of that portion of the research and development which is directed towards establishing new techniques and instruments and towards improving present methods for determining levels of radioactivity accurately and safely. The locally developed amplifier of high gain and of wide dynamic range has been shown to provide plateaus suitable for the simultaneous counting of alpha and beta particles. Commercially available amplifiers have failed to exhibit suitable plateaus when used under the same conditions. This locally developed amplifier in conjunction with the Nuclear Instruments PC1 chamber has made it possible to estimate beta energies down to 0.02 million electron volt, which is to be compared to a former lower limit of 0.1 million electron volt. A fast neutron survey meter must be simple, lightweight, portable and efficient and must provide discrimination against gamma rays. The first step, which is the design of a suitable detecting device has been successfully completed as good efficiency and good discrimination against gamma rays have been achieved. The necessary electronic circuits must now be engineered to provide the requisite simplicity lightweight and portability.
Date: May 21, 1951
Creator: Haring, M.M.
Partner: UNT Libraries Government Documents Department

A Study of Catalytic Oxidation and Oxide Adsorption for the Removal of Tritium from Air

Description: An apparatus and procedure were developed for studying the containment of tritium using catalytic conversion to the oxide followed by oxide adsorption. Data were obtained on the catalytic oxidation of elemental tritium and tritiated volatile hydrocarbons from pump oils between 23 and 538 degrees C. Oxidation efficiencies as high as 99.99997% (decontamination factor = 3.3 million) were obtained for total tritium levels of 1 ppm and a tritiated hydrocarbon level of approximately 0.2 ppb. In addition, a mathematical study was made to derive equations for the conceptual design of an "Emergency Containment System" for containment of tritium following an accidental release to room air.
Date: December 21, 1972
Creator: Bixel, John C. & Kershner, Carl J.
Partner: UNT Libraries Government Documents Department

A Summary Review of Mound Laboratory's Experience in D & D of Radioactive Facilities 1949-1973

Description: The objective of Mound Laboratory's Decontamination and Decommissioning (D&D) projects has been the effective termination of radioactive material processing facilities with no significant personnel exposures or environmental releases. This objective must be met with available resources and manpower. Mound has effectively decontaminated and/or decommissioned four major facilities in the 1949 through 1973 time period. Many minor areas were also decontaminated and/or decommissioned during this period. The major D & D projects involved the following isotopes: polonium-210, radium-226, actinium-227, and plutonium-238. To achieve a D & D status, Mound has employed several control and decontamination techniques such as: "Navy Cocooning", entombment, removal, foaming, bagging, tents, chutes, portable exhausters, dry ice, vents, bubble suits, three-zones, fire watches, painting and sealing, in-line cleaning, high pressure water blaster, and chemical cleaning.
Date: June 1, 1974
Creator: Garner, J. M. & Davis, W. P.
Partner: UNT Libraries Government Documents Department

A Surface Protective System

Description: Part of the design and development work connected with the erection of the chemistry "cave" in the "GP" Building entailed an investigation of various protective measures for materials of construction. This work was based on the observations and recommendations of personnel engaged in work at a similar installation at Argonne National Laboratory.
Date: November 1, 1950
Creator: Brown, W. T.
Partner: UNT Libraries Government Documents Department

A Technique for the Metallographic Preparation of Lead

Description: A technique is described which enables lead to be metallographically prepared to reveal the true microstructure with good edge retention. The technique consists of a series of mechanical grinding and polishing steps each of which is followed by a chemical polish. The depth of the deformed metal layer, due to grinding, was measured as well as the rate of metal removed by the chemical polish. The technique can be used to achieve relatively good results in a short period of time.
Date: October 1, 1971
Creator: Downs, Gene L. & Jones, V. Dean
Partner: UNT Libraries Government Documents Department

Techniques and Facilities for Handling and Packaging Tritiated Liquid Wastes for Burial

Description: Methods and facilities have been developed for the collection, storage, measurement, assay, solidification, and packaging of tritiated liquid wastes (concentrations up to 5 Ci/ml) for disposal by land burial. Tritium losses to the environment from these operations are less than 1 ppm. All operations are performed in an inert gas-purged glovebox system vented to an effluent removal system which permits nearly complete removal of tritium from the exhaust gases prior to their dischardge to the environment. Waste oil and water from tritium processing areas are vacuum-transferred to glovebox storage tanks through double-walled lines. Accommodations are also available for emptying portable liquid waste containers and for removing tritiated water from molecular sieve beds with heat and vacuum. The tritium concentration of the collected liquids is measured by an in-line calorimeter. A low-volume metering pump is used to transfer liquids from holding tanks to heavy walled polyethylene drums filled with an absorbent or cement for solidification. Final packaging of the sealed polyethylene drums is in either an asphalt-filled combination 30- and 55- gallon metal drum package or a 30-gallon welded stainless steel container.
Date: June 1, 1974
Creator: Rhinehammer, T. B. & Mershad, E. A.
Partner: UNT Libraries Government Documents Department

Tertiary Containment in a Multi-Room Tritium Facility

Description: An experimental system to provide tertiary containment at Mound has been upgraded to support a new multi-room tritium handling facility. This system is used to remove tritium from room air in the event of primary (process) and secondary (glovebox) containment failure. The upgraded system includes a faster response time, piping and valves that are more leaktight, and a new control panel that better indicates the system status and operating conditions.
Date: April 1, 1985
Creator: Kent, L. R.
Partner: UNT Libraries Government Documents Department

Ultrasonic Assembly of Thermoplastic Parts

Description: Four ultrasonic methods were evaluated for assembly of experimental plastic parts for detonators: (1) welding, (2) crimping and staking, (3) insertion, and (4) reactivation of adhesives. For welding, staking and insertion, plastics with low elastic moduli, such as acrylics and polycarbonate, produced the best results. Thermosetting, hot-melt, and solution adhesives could all be activated ultrasonically to form good bonds on plastics and other materials. This evaluation indicated that thermoplastic detonator parts could be assembled ultrasonically in shorter times than by present production techniques with high bond strengths and high product acceptance rates.
Date: March 31, 1970
Creator: Schurman, W. R.
Partner: UNT Libraries Government Documents Department

A Physicochemical Evaluation of the HQ-1 Core from the Pricetown I, Underground Coal Gasification Test Site

Description: Core samples of coal and rock were obtained from the HQ-1 environmental test well at the Pricetown I, Underground Coal Gasification Test Site. A comprehensive analytical program was performed to characterize the coal samples. The rocks associated with the coals are composed of clay size material containing low amounts of organic matter and hydrocarbon gas relative to the coal seams. The fine grained sediment above and below the coal seams appear to be an effective gas seal. The coals were encountered in two intervals of 1 foot and 6 feet thickness separated by 2 feet of shale. The coals are classified as high volatile A or B bituminous based on vitrinite reflectance, fixed carbon, and calorific value. Coal maceral analysis shows that the coal is heterogeneous in petrographic properties. The vitrinite group is the predominant maceral constituent. Fusinite, semi-fusinite, massive micrinite, and sporinite are present in varying amounts. The distribution of porous fusinite layers within the coal seams may be important in the reverse linkage stage of the gasification process. The coal in the bottom seam contains an average of 45.6 standard cubic feet of free methane per ton of coal. This methane may assist in initiating the gasification process. Thermal Conductivity and Laser Thermal Diffusivity experiments were also performed on selected coal samples as well as on samples of the grout used in the instrumentation wells. While the thermal conductivity values were influenced by the tars and oils generated during the heating of the coal, the laser thermal diffusivity values were obtained at sufficiently low temperatures to minimize the influence of the tars and oils.
Date: September 20, 1978
Creator: Zielinski, R. E. & Larson, R. J.
Partner: UNT Libraries Government Documents Department

Plutonium Isotopic Measurements by Gamma-Ray Spectroscopy

Description: The nondestructive assay of plutonium is important as a safeguard tool in accounting for stategic nuclear material. Several nondestructive assay techniques, e.g., calorimetry and spontaneous fission assay detectors, require a knowledge of plutonium and americium isotopic ratios to convert their raw data to total grams of plutonium. This paper describes a nondestructive technique for calculating plutonium-238, plutonium-240, plutonium-241 and americium-241 relative to plutonium-239 from measured peak areas in the high resolution gamma-ray spectra of solid plutonium samples. Gamma-ray attenuation effects have been minimized by selecting sets of neighboring peaks in the spectrum whose components are due to the different isotopes. Since the detector efficiencies are approximately the same for adjacent peaks, the accuracy of the isotopic ratios are dependent on the half-lives, branching intensities and measured peak areas. The data presented describes the results obtained by analyzing gamma-ray spectra in the energy region from 120 to 700 keV. The majority of the data analyzed was obtained from plutonium material containing 6% plutonium-240. Sample weights varied from 0.25 g to approximately 1.2 kg. The methods have also been applied to plutonium samples containing up to 23% plutonium-240 with weights of 0.25 to 200g. Results obtained by gamma-ray spectroscopy are compared to chemical analyses of aliquots taken from the bulk samples.
Date: May 1, 1976
Creator: Haas, Francis X. & Lemming, John F.
Partner: UNT Libraries Government Documents Department