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Energy Deposition by Fast Neutrons. [Part] II, Yield of the Fricke Dosimeter at 14.6 Mev

Description: A measurement of the yield of the aerated, ferrous sulfate-sulfuric acid (Fricke) dosimeter for 14.6-Mev neutrons gave a value of GF /sub Fe/sup +5/= 11.5 plus or minus 1.8. G/sub Fe/ number of ferric ions produced per 100 ev deposited. The determination combined an analysis of the energy deposit by scattering and charged particle reactions with a determination of the neutron flux by two independent means: (1) a "long counter" method and (2) an activation technique. The result is in reasonable agreement with a prediction for G/sub Fe// sup plus or minus 5/ based on measured yields of the dosimeter to irradiations by monoenergetic charged particles.
Date: November 1963
Creator: Axtmann, Robert C. & Licari, Joseph A.
Partner: UNT Libraries Government Documents Department

Nuclear Analysis of PM Long Life Core 3

Description: Introduction. Under AEC contract the Martin Company has followed up the design and construction of the PM-1 and PM-3A nuclear power plants with R&D efforts seeking improved plant efficiency, increased core life and higher operating power. The Advanced PM cores have evolved step by step, with the addition of degrees of freedom to design latitude. A first replacement core, Core 2, has been designed to achieve 50 percent greater life than PM-1 through relatively minor design changes. Core 3 realizes the potential extensive modifications in the fuel element and control element configurations. This paper outlines an analysis effort undertaken to define what may be called a performance profile over a range of configurations of interest for Core 3. It should be emphasized that this is a parametric or concept study and not a final design effort. The results of this study clearly indicate that a lifetime of 100 Mw-yr can be obtained from a 7 ft pressurized water core. If employed as a 10-Mw heat source for present PM equipment, this core has a lifetime approaching that of the plant equipment, 90,000 full-power hours. Core 3 will be suitable for applications demanding up to 40-Mw operating thermal power.
Date: November 1963
Creator: Bagley, Raymond. & George, Critz.
Partner: UNT Libraries Government Documents Department

Effect of Fluoride Ions on the Aqueous Corrosion of Zirconium Alloys

Description: Abstract. A review has been made of the effects of fluoride ions on the corrosion behavior of zirconium alloys in high-temperature water. Corrosion was found to occur as the result of contamination of the water or the zirconium surface. A major source of fluorides is undue delay in rinsing the HF-HNO3 pickling solution during surface preparation. The oxide on corrosion-resistant material has been found to contain up to 7600 ppm fluoride from this source. The threshold concentration of fluoride in the oxide film which produces poor corrosion resistance ranges from 8500 to 17,000 ppm. Accelerated corrosion from fluorides in water at 300 to 360 C occurs at about 100 ppm, although increased corrosion has been reported at 10 ppm fluoride in water at 300 C. Fluorocarbon plastics degrade and contribute fluorides to the high-temperature water or to the alloy surface when in direct contact with zirconium. Chlorides (1 to 10,000 ppm) and iodides (1270 ppm) do not adversely affect the corrosion behavior of zirconium alloys in water at 360 C. The mechanism of corrosion is not well understood but apparently is related to the formation of insoluble zirconium oxyfluorides during pickling and during exposure to fluoride-contaminated water.
Date: November 1963
Creator: Berry, Warren E., 1922-
Partner: UNT Libraries Government Documents Department

A High Speed Readout for Multi-Channel Pulse Height Analyzers

Description: From American Nuclear Society Meeting, New York, Nov. 1963. In computer-coupled automated activation analysis such as in the Mark II system, conventional methods of data readout impose a serious restriction on the minimum handling time per sample. A data coupler for operating between the data accumulation system and the computer tape unit was developed which contributes nothing to the handling time per sample, does not distort the data, and prepares the data for direct computer entry. In addition to activation analysis, the coupler may be used to obtain successive spectra separated in time by 0.16 sec in the study of short-lived isotopes.
Date: November 1963
Creator: Wilkins, W. W.; Fite, L. E. & Wainerdi, Richard E., 1931-
Partner: UNT Libraries Government Documents Department

Automatic Exit Steam Quality Control for Boiling Water Reactors

Description: From American Nuclear Society Meeting, New York, Nov. 1963. The need for control of the flow distribution and/or steam quality in boiling reactors is discussed. A quality control device is being developed which consists of an entrance venturi and an exit venturi for measuring the flow rates into and out of the channel, means for comparing the two flow rate signals, and a value for regulating the flow rate. This device can be used either as a constant quality device or as a controlled-quality device. Results are given of air-water studies of two-phase flow in a vertical venturi.
Date: November 1963
Creator: Gall, D. A. & Doyle, E. F.
Partner: UNT Libraries Government Documents Department

Feasibility of a Liquid Phase Chemonuclear Ozone Process

Description: At the Chemonuclear Workshop held at Brookhaven National laboratory in November 1962 it was pointed out that the production of ozone from oxygen by a liquid phase fission fragment chemonuclear process appears to have reasonable economic potential. The maximum theoretical reaction yield for the formation of ozone from oxygen is a "G" value of 68 molecules for 100 ev based on heat of reaction data. The authors felt a "G" value of 15 to be reasonable for this study. the reactor system chosen has liquid oxygen as its moderator and the operating pressure and temperature were selected so as to allow boiling of the oxygen-ozone mixture. The total plant investment cost is estimated to be in the range of $100,000,000. Other system designs will be considered in the future.
Date: November 19, 1963
Creator: Cagnetta, J. P.; Goellner, D. & Steinberg, M.
Partner: UNT Libraries Government Documents Department

Fluxes and Reaction Rates in the Presence of Interferring Resonances

Description: The effects of competition between resonances of different isotopes were investigated. Flux and reaction rate calculations on a Pu/sup 239/-- U/sup 238/ system revealed that U/sup 238/ exhibits both self-shielding and interference effects, the latter becoming noticeable at enrichment of a few per cent. Gold activation was also found to be depressed by the presence of U, but was insensitive at low enrichment values, Investigation of the Pu/sup 239/ resonance integral showed an asymmetric effect involving both interference between potential and resonant scattering and interference with resonance absorption in another isotope. The interference scattering arising in each resonance level had a notable effect on the average change in the Doppler coefficient. (D.C.W.)
Date: November 1963
Creator: Kelber, Charles N.
Partner: UNT Libraries Government Documents Department

Asymptotic Neutron Spectra in Multiplying Media

Description: Asymptotic low energy neutron spectra have been measured for two multiplying systems. The reentrant hold spectrum (scalar flux) and the surface leakage spectrum were obtained for both assemblies using the pulsed-source chopper technique at the RPI linear accelerator.
Date: November 1963
Creator: Slovacek, R. E.; Fullwood, R. R.; Gaerttner, Erwin Rudolf, 1911- & Bach, D. R.
Partner: UNT Libraries Government Documents Department

Behavior of Irradiated Metallic Fuel Elements Exposed to Nuclear Excursion in TREAT

Description: In fast reactor safety studies, it is imperative to know the effects of temperature excursions on the fuel elements. Previous controlled out-of-pile experiments on the behavior of uranium fuel elements under meltdown or near-meltdown conditions have been performed using direct electrical resistance heating or furnace heating. As a step toward obtaining more complete information on reactivity effects accompanying fuel meltdown, the behavior of irradiated EBR II and Fermi A samples under transient nuclear heating in TREAT has been studied. The experiment results obtained indicate that effects of prior irradiation can produce significant effects upon reactivity changes produced by meltdown of metallic fast reactor fuel pins.
Date: November 1963
Creator: Monaweck, J. H.; Dickerman, Charles Edward, 1932- & Sowa, E. S.
Partner: UNT Libraries Government Documents Department

Effect of Radiation on Mechanical Properties of CVTR Pressure Tube Material

Description: An essential part of establishing the acceptability of warm extruded Zircaloy-4 for the CVTR pressure tube application was the determination of irradiation effects on mechanical properties of the alloy. Representative specimens were irradiated in low temperature process water in the WTR for simulated two, three and five year exposure. The effects of this irradiation were then evaluated in terms of changes in tensile, impact and creep properties. The experiment results concluded that the irradiation-induced changes in mechanical proprieties will not introduce any operational hazard to the CVTR pressure tube under anticipated operating conditions.
Date: November 1963
Creator: Smalley, W. R.
Partner: UNT Libraries Government Documents Department

The Determination of k∞ From Measurements on a Small Test Sample in a Critical Assembly

Description: Abstract. The determination of the infinite multiplication factor, k∞ , from measurement son a small test sample was investigated by both theoretical and experimental techniques. Theoretical relations were developed to calculate the error in the measurement due to a mismatch between the flux ratios in the critical assembly and those of the test sample. Experiments were carried out at the Hanford Laboratory of the General Electric Company with the PCTR, to obtain values of the multiplication factor for comparison with the theoretical results. Calculations with two-group theory gave results that agreed with the experimental results when the test sample, with natural uranium fuel, was surrounded by a buffer region of the same material. When this buffer region was loaded with highly enriched fuel, the errors in the measured values were not predicted by the two-group theory. Three-group theory relations were derived which gave calculated values in agreement with the experimental values and indicated that a mismatch of the epithermal neutron group leads to the measured differences in the value of k∞ for the two buffer types.
Date: November 1963
Creator: Lanning, David Dayton
Partner: UNT Libraries Government Documents Department

Sodium Separation From Biological Material

Description: This study is part of a research into trace element physiology of fresh water snails. As an average, biological materials contain [approximately] o.0% (fresh weight) NaCl ; this means [approximately] 3540 mg Na/1 (in snails, 0.4% NaCl [approximately] ms/1). Under these conditions, the application of neutron activation plus gamma spectrum analysis for the study of most trace elements as a routine method, is difficult. We will narrow down the scope some more and consider only the interference between Na24 and Cu64.
Date: November 1963
Creator: Spronk, N.
Partner: UNT Libraries Government Documents Department

A Talk on NMR Applied to Polymer Research Given at the Eastern Analytical Symposium - November 14, 1962

Description: The nature and types of internal molecular and thermal motions that polymer chains and polymer segments undergo have a great bearing on the physical behavior of polymeric solids. A relatively new tool is now available that permits us to observe and study internal thermally-induced motions directly at the atomic or molecular level rather than from macroscopic observations. this tool is nuclear magnetic resonance spectroscopy. This talk discusses (1) the nature of nuclear magnetic resonance, (2) NMR line shapes and the influence of temperature, (3) NMR line widths and second moments as a function of temperature, and (4) lists six general conclusions.
Date: November 14, 1962
Creator: Sauer, John A.
Partner: UNT Libraries Government Documents Department

Effect of Eddy Diffusion on Temperatures in a Fixed Bed, Particulate-Fueled Nuclear Reactor

Description: Abstract: To assess diffusion's importance, the temperature distribution in a cylindrical reactor is derived for a coolant with uniform properties and velocity, taking into account both radial and axial diffusion, for a cosine-J0 power distribution. The fractional temperature rise of the coolant is found to be [chemical formula] where E(z) = [sin(z) + sin(Z)]/2 sin(Z), z= π x/2′, x is the axial distance from the core center, -H and ′ are the core half-height and extrapolated half-height, -H≤x≤H; Fn = 1/J0(Pn)·[(Pn/2.405P)2-10, J1(Pn) = 0, P= R/R′ = core radius/extrapolated radius, ρ = r/R, r = radial distance from axis, 0≤r≤R; an = = βnH/Z, 2 Aβn + 1 =[1 + 4αβ(Pn/R)2]½, A = axial diffusivity /u, B = radial diffusivity /u, u = coolant axial velocity, and [chemical formula]. The expression is evaluated for a variety of values for all the parameters, and the results are discussed analytically and presented in tables and graphs. The effect is dependent upon the relative size of the diffusion eddies in comparison with the dimensions of the reactor. The eddy diffusivity is proportional to the size of the particles in the bed and is about ten times larger axially than radially. A small core with large fuel particles will be affected by eddy diffusion, thereby reducing hot spots, but a large core with small particles will not. For a core 8 ft in diameter cooled by sodium flowing at 2 ft/sec, the effect is perceptible with 2-in. particles, but not with 0.2-in. particles.
Date: November 1963
Creator: Barker, James J. & Benenati, Robert F.
Partner: UNT Libraries Government Documents Department

The Diffusion of Fast Neutrons

Description: From American Nuclear Society Meeting, New York, Nov. 1963. The use of the asymptotic solution to the one-velocity transport equation is considered. The angular distribution for fast neutron elastic scattering by heavy elements is discussed. An exponential angular distribution on is assumed to simplify the decay length calculation. The diffusion length of 1 to 15 Mev neutrons in iron is calculated, as well as the vector flux angular dependence. The asymptotic solution for an arbitrary angular distribution of a plane delta -function source is also found. An isotropic source is investigated, and some applications of the model are examined.
Date: November 1963
Creator: Francis, N. C.; Brooks, E. J. & Watson, R. A.
Partner: UNT Libraries Government Documents Department