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Mn$sup 56$ COINCIDENCE COUNTING FACILITY

Description: A two-stage absolute counting facility for large liquid samples of aqueous Mn/sup 56/SO/sub 4/, primarily intended for better than 1% precision measurements of neutron source strengths by the manganese bath technique, is described. Two-liter samples are counted in a gamma - gamma coincidence arrangement that greatly improves long-term reproducibility at some sacrifice in counting statistics; this sacrifice is, however, lessened through a novel pulse- distribution scheme that allows fall utilization of the output of each detector channel. The system is calibrated on an absolute scale through another unit which counts aliquots of strongly activated samples mixed with liquid scintillator in a 4 pi BETA / gamma coincidence mode. The entire facility is designed to be readily adaptable to other radioisotope-counting requirements. (auth)
Date: August 1, 1963
Creator: DeVolpi, A.; Porges, K.G.A. & Larsen, R.N.
Partner: UNT Libraries Government Documents Department

Corrosion Product Activity Distribution Across the Chemical Process System in the Consolidated Edison Thorium Reactor Plant

Description: ABS>A study was performed to determine the corrosion product and water impurity activities in the CETR Chemical Process System. These activities were calculated as functions of the reactor operating time, primary loop blowdown purification rate, and decay time following removal from the primary loop. For the design blowdown purification rate chosen, isotopes that are important to the design of radiation shielding include Co/sup 60/ and Co/sup 58/ Fe/sup 55/, Cr/ sup 51/, and Mn/sup 56/. A simplified mathematical model is used to represent the physical situation; however, the magnitude of the activities, taken at the end of core life to represent the most conservative case, is considered sufficiently accurate for engineering calculations. (auth)
Date: September 1, 1958
Partner: UNT Libraries Government Documents Department

Residual Radiation of the LRL 184-Inch Cyclotron

Description: Residual radioactivity at the Lawrence Radiation Laboratory 184-Inch Cyclotron was measured during November 1960. The study was conducted along three principal lines: (1) general survey of radiation levels in the cyclotron vault, (2) activation of foils placed near the cyclotron, and (3) gamma-ray spectra of the cyclotron gap region, including dee structure. Initial radiation levels were less than 8 r/hr which dropped to abcut 10 mr/hr after 48 hr. The observed activities induced in copper foils were Cu/sup 64/ and Co/sup 58/; in iron foils, Mn/sup 52/, Mn/sup 54/, and Mn/sup 56/; in aluminum foils Na/sup / 2>s/sup 4/ The gamma-ray spectra from the gap region included two intense long-lived peaks, at 510 and 810 kev, caused principally by Co/sup 58/. (auth)
Date: July 12, 1961
Creator: Boom, R. W.; Toth, K. S. & Zucker, A.
Partner: UNT Libraries Government Documents Department

RADIOISOTOPIC INVESTIGATION OF OMR COOLANTS. PART I. OMRE OPERATION, JANUARY 1958-AUGUST 1960

Description: Over 30 radioisotopes were identified in the coolant of the OMRE during the period from January, l958 through August, l960. The principal gamma-emitting isotopes measured were the corrosion products: Mn/sup 56/, Fe/sup 59/ and Mn/sup 54/ the principal beta emitters were: P/sup 32/, H/sup 3/,S/sup 35/, Fe/sup 55/, and C/sup 14/. The total (gamma plus beta) activity of the coolant during normal reactor operations was estimated to have been less than l.08 mu c/gm of coolant, with Mn/sup 56/ contributing approximately 80% of the detected process radiation. (auth)
Date: December 1, 1961
Creator: Baurmash, L.; Wode, S.J. & Lawrence, D.C.
Partner: UNT Libraries Government Documents Department

The {sup 59}Co(n,{alpha}) reaction from threshold to 30 MeV

Description: Neutron-induced reactions that result in alpha-particle emission have been investigated for the target nucleus {sup 59}Co over the neutron energy range from threshold to 30 MeV with the spallation neutron source at WNR/LAMPF. Double-differential cross sections were measured at alpha-particle emission angles of 30, 60, 90 and 135{degree}. Integrated cross sections agree well with activation data below 14 MeV where only the {sup 59}Co(n,{alpha}){sup 56}Mn reaction contributes to alpha-particle emission. At higher energies, the integrated alpha-particle emission cross section exceeds the activation data. The results will be interpreted in terms of statistical and pre-compound reaction mechanisms. The sensitivity to nuclear level density parameters will be discussed.
Date: June 1, 1994
Creator: Lee, T. M.; Sterbenz, S. M. & Bateman, F. B.
Partner: UNT Libraries Government Documents Department

Environmental status of the Hanford Reservation for December 1966. (Annual summary)

Description: Data are summarized on levels of radioactivity in environmental samples collected at Hanford during 1966, including detailed data on samples collected during December. Data are included on the radioactivity in fallout from Chinese and Russian nuclear weapons test, samples of drinking water and Columbia River water, the /sup 56/Mn content of Columbia River water sampled at various locations, the /sup 131/I content of gaseous wastes and surface waters, and the radioactivity of soil samples from the chemical separations liquid waste treatment and disposal area. The radiation dose to personnel during the year from all enviromnentl sources was estimated to be less than 0.3 percent of the applicable limits. (CH)
Date: March 20, 1967
Creator: Essig, T.H. & Hall, R.B.
Partner: UNT Libraries Government Documents Department

Nuclear Reactions Induced by Pions and Protons

Description: Effects due to elementary particle-like collisions within nuclear matter have been observed in several nuclear reactions caused by pions and protons. Simple nuclear reactions of the form ZA(a,an)Z/sup A-1/ and Z/sup A/(a,ap)(Z-1)/ sup A-1/ have excitation functions that are sensitive to changes in the elementary-particle cross sections. The excitation function for the reaction C/ sup 12/( pi /sup -/, pi /sup -/n)C/sup 11/ is measure d from 53 to 1610 Mev by bombarding targets of plastic scintillator with pions. The intensity of the pion beam is monitored with a two-counter telescope and 40 Mc scaling system. The scintillator target is mounted on a phototube and becomes the detector for the carbon-11 positron activity. Corrections are made for muon contamination in the beam, coincidence losses in the monitor system, carbon-11 activity produced by stray background at the accelerator, carbon-1l activity produced by secondaries in the target, and the efficiency of the carbon-11 detection system. The C/sup 12/( pi /sup -/, pi /sup -/n)C/sup 11/ cross sections rise to a peak of abo ut 70 mb at 190 Mev, that corresponds to the resonance in freeparticle pi /sup -/n scattering at 190 Mev. Calculations based on a knock-on'' collision mechanism and sharp-cutoff nuclear density reproduce the shape of the experimental excitation function, but the magnitudes of the calculated values are low by a factor of six, The calculation shows that the C/sup 12/( pi /sup -/, pi /sup -/ n)C/sup 11/ reaction occurs in the nuclear s urface region at all bombarding energies, The contributions to the ( pi /sup -/, pi /sup -/n) reaction predominate on the front surface of the nucleus in order to give the pion the maximum probability of escaping. The excitation functions for the reactions ured radiochemically from 400 Mev to 6.2 Bev. The slight increase in ...
Date: November 27, 1962
Creator: Reeder, P. L.
Partner: UNT Libraries Government Documents Department

An anion exchange-precipitation procedure for the determination of Na{sup 24} in reactor effluent water

Description: The isotope Na{sup 24} is one of the major short half-life constituents of reactor effluent water. It has a half-life of 15 hours and decays of emission of a 1.39 MeV maximum beta particle. Other radioisotopes present in reactor effluent water from which Na{sup 24} must be separated are Si{sup 31}, P{sup 32}, Mn{sup 56}, Cu{sup 64}, As{sup 76}, Sr{sup 91--92}, Ba{sup 139--140} and rare earths. This report describes a rapid and very simple method for the quantitative determination of Na{sup 24} in a radiochemically pure form.
Date: August 10, 1955
Creator: Perkins, R. W.
Partner: UNT Libraries Government Documents Department

PHYSICS DIVISION SUMMARY REPORT

Description: Half lives were determined for 10 transitions in low-lying energy levels, excited by slow neutron capture, in Mn/sup 5//sup 6/, Rh/sup 1//sup 0// sup 4/, Cu/sup 6//sup 4/, Al/sup 2//sup 8/, and I/sup 1//sup 2//sup 8/. Internal ma gnetic fields at the nuclei of Fe/sup 5//sup 7/ and Sn/sup 1//sup 1//sup 9/ in various magnetic media were studied with the Mossbauer effect, and their nuclear Zeeman effects were snalyzed. Energy spectra, angular distributions, and reduced widths were obtained for (d,t) reactions on Fe/sup 5//sup 4/, Fe/sup 5//sup 8/, Ni/sup 5//sup 8/, Ni/sup 6//sup 0/, and Ni/sup 6/>s1< s, and the data used to provide information on the ground-state wave functions of these isotopes. The beta and gamma radiations associated with Er/sup 1//sup 7//sup 2/ decay were measured and a decay scheme proposed for Er/sup 1//sup 7//sup 2/. The level structure of F/sup 2//sup 0/ at 1 to 150 kev above the neutron binding energy was studied by the F/sup 1//sup 9/(n,n)F/sup 1//sup 9/ ess. The region around 100 kev was found to contain a cluster of levels. A polystyrene film was prepared with a thickness of 530 A and its vacuum ultraviolet spectrum determined in the range 1100 to 2300 A. Experimental data on the kinetic energies of fragments from electron bombardment of ethylene and acetylene are interpreted in terms of a "temperature." The form factors for the inelastic scattering of high-energy electrons are calculated for Sm/sup 1//sup 5//sup 2/ with the collective model of a deformed nucleus. A singleparticle rotational model, which includes band mixing, was found to give a qualitative fit to many of the properties of the low- lying states in Fe/sup 5//sup 7/ with the exception of those depending on the intrinsic wave function of the 1/2/sup -/ ground state. (D.L.C.)
Date: March 1, 1961
Partner: UNT Libraries Government Documents Department

RADIOCHEMISTRY DURING START-UP AND EARLY OPERATION OF THE NUCLEAR SHIP SAVANNAH. Final Report

Description: It was demonstrated that the radioactivity content of the primary system of the N.S. Savannah reactor plant was small and normal during the period of initial criticality and start-up, and during the sea trials and acceptance tests. The principal radioactive constituents (/sup 56/Mn, /sup 41/Ar, /sup 13/N and / sup 18/F) are either intrinsic to the primary system of the pressurized water reactor or are normally found in the coo1ant in concentrations comparable to those observed in this program. The /sup 56/Mn concentrations observed at the various reactor power levels were slightiy higher, relative to those for the other nuclides, than those observed in similar reactor plants. This slightly increased concentration is attributable to the fact that the coolant of this reactor was generally maintained between pH6 and pH7, whereas the primary coolants of the other plants were maintained at somewhat higher pH values. Data for fission product concentrations in the primary coolant indicate that their only significant source is uranium contamination of the reactor core surfaces. The observed concentrations do not represent any significant hazard or potential difficulty in plant operation. The small value of 5.6 x 10/sup -2/ mu g/cm/sup 2/ for the surface density of uranium indicates that no significant contamination of these surfaces occurred during core fabrication. No significant defect in a fuel element cladding was detected during the period in which these measurements were performed. The efficiency of the demineralizer for removal of anionic and cationic radionuclides from the primary coolant was shown to exceed 90%. Volatile radionuclides were the only radioactive constituents found in the demineralizer effluent. Data obtained for the concentrations of gross radioactivity in the waste tanks were maintained below the maximum permissible concentrations for discharge to the environment. On the basis of these radiochemistry studies, it may be concluded that the ...
Date: July 1, 1962
Creator: Battist, L; Winnowski, W S; Dieterly, D K & Koch, R C
Partner: UNT Libraries Government Documents Department

Application of nuclear resonance scattering for in vivo measurements

Description: Nuclear resonance scattering is applied in our laboratory to measure hepatic and cardiac iron overload. For iron analysis, a gaseous source of 4 mg MnCl/sub 2/ is introduced into an evacuated quartz vial. Following irradiation in a nuclear reactor, /sup 56/Mn decays by beta emission to the 847-keV level of /sup 56/Fe, which subsequently decays to the ground state of /sup 56/Fe with a 7 ps half-life. The principal aim of this work is to evaluate the efficacy of the iron chelation therapy. Serial measurements over a time period of 6 to 12 months of a given patient will enable us to see how the iron is removed from the critical organs.
Date: January 1, 1983
Creator: Wielopolski, L.; Vartsky, D. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Determination of Mn sup 56 in reactor effluent water

Description: The isotope Mn{sup 56} is the major short half-life constituent of reactor effluent water. It has half-life of 2.59 hours and decays by emission of a 2.86 mev maximum beta to stable Fe{sup 56}. This report describes a rapid method for the quantitative determination of Mn{sup 56} in a radiochemically pure form for use as a routine control procedure. A carrier-precipitation procedure has been developed which successfully separates Mn{sup 56} from other radioisotopes in reactor effluent water. It involves addition of Mn{sup ++} carrier to the sample followed by oxidation to MnO{sub 4}, removal of radioactive cations by stirring with Dowex 50 cations resin, and precipitation as MnO{sub 2}{center dot}xH{sub 2}O. The MnO{sub 2}{center dot}xH{sub 2}O is dried and weighed and its radioactivity measured by beta counting. A self-adsorption and self-water and self-scatter curve for Mn{sup 56}O{sub 2}{center dot}xH{sub 2}O was prepared by using a Mn{sup 56} spike prepared from reactor effluent water. For samples of interest a correction for self-absorption and self-scatter will be unnecessary. 2 refs., 2 figs., 3 tabs.
Date: November 9, 1954
Creator: Perkins, R.W.
Partner: UNT Libraries Government Documents Department

Nuclear resonance fluorescence: new technique for in vivo iron determination in man

Description: A technique for the measurement of body iron stores utilizing nuclear resonant scattering of gamma-rays has been developed. 847keV photons emitted from a gaseous /sup 56/MnCl/sub 2/ source are resonantly scattered from /sup 56/Fe present in the liver and are detected by two large volume Ge(Li) detectors. Due to the very narrow resonance of the absorption cross section the technique is very specific to the element under investigation. The spatial uniformity of activation, the sensitivity of the detection system and the limits of detection have been investigated. Measurements were made of liver of a man-like phantom. The sensitivity and the limit of detection obtained for the NRS technique developed in this study are adequate for detection of iron in livers of normal individuals and are certainly sufficient for livers of persons with iron overload.
Date: January 1, 1979
Creator: Vartsky, D.; Ellis, K.J. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Production test 105-2-P (Supplement A) - Activity of pile discharge water (Activation of manganese and iron)

Description: This report discusses the Production Test 105-2-P (Supplement A) -- Activity of Pile Discharge Water. Previous studies of pile discharge water have shown that one of two processes is responsible for the large but variable amount of Mn{sup 56} activity present in the water. One process is the production of Mn{sup 56} by the reaction Mn{sup 55} on manganese impurity in the water. The amount of such impurity has been shown to be too small to produce the observed amount of Mn{sup 56} unless the mean irradiation time is increased by a large factor due to temporary sticking of manganese on the surfaces in the tubes. The other process is the production by the reaction Fe{sup 56} on iron in the film. The present production test was designed to determine which of these processes is responsible for the troublesome Mn{sup 56} activity and to what extent the activity is increased due to sticking of manganese or iron in the tubes. 4 figs.
Date: May 8, 1946
Creator: West, J.M.
Partner: UNT Libraries Government Documents Department

Use of nuclear resonant scattering of gamma rays for in vivo measurement of iron

Description: A technique for determination of elements in human body in-vivo, utilizing nuclear resonant scattering of gamma rays has been developed. 847 keV photons emitted from a gaseous /sup 56/MnCl/sub 2/ source are resonantly scattered from /sup 56/Fe present in the body. The detection of these gamma rays is used to estimate the iron content of the liver or heart of patients. Details of the calibration procedure and potential molecular effects are described.
Date: January 1, 1981
Creator: Vartsky, D.; Wielopolski, L.; Ellis, K.J. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Transport and deposition of activation products in a helium cooled fusion power plant

Description: The transport and deposition of neutron activation products in a helium cooled tokamak fusion power plant are investigated. Stainless steel is used as coolant channel material for a helium/steam system. The important gamma emitting nuclides /sup 56/Mn, /sup 54/Mn, /sup 57/Co, /sup 58/Co, /sup 60/Co, /sup 51/Cr, and /sup 99/Mo are considered. The dominant release mechanism identified is direct daughter recoil emission from (n,x) type reactions. Corrosion and evaporation are discussed. The radionuclide inventory released by these mechanisms is predicted to exceed 1 x 10/sup 4/ Ci for a reference reactor design after only several days of operation, and approach 3.5 x 10/sup 4/ Ci in equilibrium. A mass transport model is then used to predict the deposition pattern of this inventory in the reactor cooling system.
Date: September 1, 1980
Creator: Bickford, W.E.
Partner: UNT Libraries Government Documents Department

Estimates of Columbia River radionuclide concentrations: Data for Phase 1 dose calculations

Description: Pacific Northwest Laboratory is conducting the Hanford Environmental Dose Reconstruction Project to estimate the radiation doses people may have received from historical Hanford Site operations. Under the direction of an independent Technical Steering Panel, the project is being conducted in phases. The objective of the first phase is to assess the feasibility of the project-wide technical approach for acquiring data and developing models needed to calculate potential radiation doses. This report summarizes data that were generated for the Phase 1 dose calculations. These included monthly average concentrations of specific radionuclides in Columbia River water and sediments between Priest Rapids Dam and McNary Dam for the years 1964 to 1966. Nine key radionuclides were selected for analysis based on estimation of their contribution to dose. Concentrations of these radionuclides in the river were estimated using existing measurements and hydraulic calculations based on the simplifying assumption that dilution and decay were the primary processes controlling the fate of radionuclides released to the river. Five sub-reaches between Priest Rapids Dam and McNary Dam, corresponding to population centers and tributary confluences, were identified and monthly average radionuclide concentrations were calculated for each sub-reach. The hydraulic calculations were performed to provide radionuclide concentration estimates for time periods and geographic locations where measured data were not available. The validity of the calculation method will be evaluated in Phase 2. 12 refs., 13 figs., 49 tabs.
Date: May 1, 1991
Creator: Richmond, M.C. & Walters, W.H.
Partner: UNT Libraries Government Documents Department

Container effects in /sup 56/Mn sources for iron determination in the human body by NRS technique

Description: Iron overloads in liver and heart are detected in vivo by nuclear resonant scattering (NRS) technique. The method is based on the resonant scattering of 847 keV gamma ray from the first nuclear level in /sup 56/Fe. The source of radiation is provided by /sup 56/MnCl/sub 2/ maintained in a gaseous phase in an evacuated quartz vial at 1030/sup 0/C. It was observed that the time dependent NRS yield, from an iron slab, differed appreciably from the 2.58 h half-life of /sup 56/Mn. Inasmuch as the NRS system responds only to the source in the gaseous phase, the discrepancy is attributed to the interaction between the gaseous source and the walls of the vial. Fused silica vials and fused quartz vials demonstrate entirely different time behavior.
Date: January 1, 1982
Creator: Wielopolski, L.; Vartsky, D.; Rorer, D.C.; Levy, P.W. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

Calculation of /sup 59/Co neutron cross sections between 3 and 50 MeV

Description: Knowledge of the /sup 59/Co(n,p), (n,..cap alpha..), and (n,xn) cross sections up to 50 MeV are necessary to satisfy priority dosimetry data needs of the FMIT facility. Since experimental data extend only to 25 MeV in the case of (n,xn) reactions (and lower energies for the others), these cross sections as well as those from competing reactions were calculated for neutron energies between 3 and 50 MeV. Neutron optical parameters were determined that were valid from several hundreds of keV to 50 MeV. Other parameters were determined or verified through analysis of various experimental data types. A basis for complete and consistent nuclear model calculations of n + /sup 59/Co reactions was thus provided. 9 figures, 1 table.
Date: January 1, 1980
Creator: Arthur, E.D.; Young, P.G. & Matthes, W.K.
Partner: UNT Libraries Government Documents Department