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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

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

The Education, Experience, Training, and Certification of Reactor Operators at AEC-Owned Reactors

Description: Results of a questionnaire survey are presented on reactor supervisor and operator education, experience, and training, and on certification procedures by reactor category. The questionnaires were obtained from 362 supervisors, 393 operators, 44 supervisor trainees, and 139 operator trainees.
Date: October 31, 1964
Creator: Wilgus, Walter S.; McCool, Whittie J. & Biles, Martin B.
Partner: UNT Libraries Government Documents Department

Planar Dynode Multipliers for High-Speed Counting

Description: Technical report discussing a new high-speed electron multiplier using a planar dynode configuration. This multiplier has a total transit time significantly shorter than available in conventional structures of equivalent gain. It also features rise-times generally less than three nanoseconds while providing the large sensitive area of an unfocused configuration. Two basic types of planar dynodes are employed: transmission secondary emission thin films as the early multiplier stages and silver-magnesium modified mesh multipliers as the high current output stages.The relevant gain and pulse-response data for these two types of dynodes are presented. The structure is quite flexible and permits the number and types of dynodes to be easily tailored to a specific application. In particular it will be shown how the number of mesh-type dynodes may be altered to effect a trade-off between current handling capabilities and rise-time characteristics. Several possible combinations of these planar dynods have been incorporated in photomultipliers whose gain, dark current, pulse response, and operating life are discussed.
Date: February 26, 1964
Creator: Sapp, W. W. & Sternglass, Ernest J.
Partner: UNT Libraries Government Documents Department

Application of the Variational Method to the Calculation of the Time Dependence of the Neutron Flux in Small Pulsed Slabs, Cylinders and Spheres

Description: The variational method is applied to the monoenergetic time dependent transport equation to obtain a simple relation for the asymptotic decay constant in small pulsed assemblies. The results indicate that flat trial functions may be a reasonable representation of the flux distributions in the thin slab limit. This approach is superior to many of the usual transport approximations.
Date: December 16, 1963
Creator: Judge, F. D. & Daitch, Paul B. (Paul Bernard), 1925-
Partner: UNT Libraries Government Documents Department

Wire Chamber -- Computer System

Description: First paragraph of report: M. Neumann and H. Sherrard reported the development of a wire spark chamber experiment toward receiving digitized spark information. Since late 1962 our effort has been directed toward a wire-chamber with a core memory, using standard ferrite cores, and toward an on-line operation between spark chamber and computer.
Date: June 1964
Creator: Bounin, J.; Miller, R.; Neumann, M.; Sarma, J. & Sherrard, H.
Partner: UNT Libraries Government Documents Department

Control of the Dissolved Gases in the Moderator of the HWCTR

Description: The Heavy Water Components Test Reactor (HWCTR) is used to test prototype fuel elements for power reactors that are moderated with heavy water and fueled with natural or slightly enriched uranium. During the initial critical experiments in the HWCTR, it was observed that there were unexpected variations in nuclear reactivity. Investigations revealed that this effect was due to bubble of helium gas appearing and disappearing in the moderator. An examination of the expected operating conditions of the HWCTR and the solubility of helium in D2O showed that it was possible during normal operation for the helium content of the moderator to exceed saturation and thus for helium to appear as bubbles in the moderator. The possibility of helium bubbles appearing in the moderator because of solubility characteristics was eliminated by modifications to the process system so as to maintain the gas content of the moderator appreciably below saturation.
Date: September 20, 1963
Creator: Arnett, L. M.
Partner: UNT Libraries Government Documents Department

Sorption Measurements in Ultrahigh Vacuum at Constant Pressure

Description: Introduction. Sorption of gases by surfaces is the primary step in many heterogeneous processes. Because sorption processes are in general pressure-dependent, and very fast at normal pressures, low pressure system are mandatory. In gas-metal interaction studies the flash filament technique with ribbons and filaments and Wagener's technique with evaporated films allow observations at the requisite low pressures. However, these method have two major drawbacks: (1) Since the pressure changes during the sorption experiment, pressure-dependent parameters can only be obtained from indirect evidence; (2) The pressure change in the sorption cell during the experiment may cause significant interaction between the sample and the rest of the system and thus experimental data must be corrected for this effect. These drawbacks have been eliminated in a new approach based on a flow system in which the sample is exposed to constant pressure. This new technique has been employed for the study of adsorption and absorption of gases by filaments and evaporated films. This method can also be used for studying gas-metal solution equilibria.
Date: October 1963
Creator: Gibson, Richard.; Bergsnov-Hansen, B.; Endow, Noboru. & Pasternak, R. A.
Partner: UNT Libraries Government Documents Department

Design Review and Safety Analysis of Experiments in ORNL Research Reactors

Description: Since 1943 when the oak Ridge Graphite Reactor was put into operation, literally thousands of individual irradiation have been performed in this reactor and in other ORNL research reactors. Over the years there have been many minor incidents caused by experiments. Such incidents have provided a basis cor continued improvement in experiment design review and safety-analysis procedures. The reports lists the Design Review and Safety Analysis (1) objectives, (2) principles and rules of design, and (3) limits of application of the review process. The report includes a review of 19 incidents at ORNL research reactors.
Date: October 1963
Creator: Stanford, L. E. & Costner, R. A., Jr.
Partner: UNT Libraries Government Documents Department

Operational Control Rod Reactivity Worths From Observed Heat Generation Rates

Description: Introduction. The reactivity difference associated with a reactor change can be simply related to the coincident changes in the neutron loss and generation rates. Unfortunately, in many instances these rates are difficult to measure directly during high-level operation; thus relativity values are normally found by other methods such as buckling calculations or low-level rising period measurements. However, with certain applicable control rod systems, it may be feasible to use heat generation rate in the rods as a measure of the reactivity-compensation effect. The neutron absorption rate in the Hanford reactor control rods can be determined under equilibrium conditions (and without disturbing these conditions) from the heat transfer rate to the control rod coolant. This information, when combined with a measurement of the change in reactor leakage caused by rod insertion, allows the calculation of control rod strength.
Date: October 1963
Creator: Fredsall, J. R. & Bowers, C. E.
Partner: UNT Libraries Government Documents Department

Selection of Personnel for Reactor Operator Training

Description: Over the past six years, the hiring practices of the Reactor Operations Division of Argonne National Laboratory have been conducted to determine the highest level of personnel who would be willing to remain in the position of reactor operator. We have discontinued the hiring of personnel who have a bachelor's degree from an accredited institution or who are close to receiving such a degree. We now hire men from three general categories: (1) graduates from two-year technical institutes, (2) men who have had a number of years of experience in related operating jobs such as the petroleum industry or the chemical industry, and (3) men who have served in the nuclear programs of the armed forces. The following tests are given: (1) Wonderlic personnel Test, score above 43 percentile is mandatory, (2) Oral Directions Test, score above 80 percentile is expected, (3) mechanical Comprehension Test, score above 80 percentile is expected, (4) Arithmetic Reasoning Test, score above 60 percentile is expected, and (5) Primary Mental Abilities Test, used primarily as a check on the other tests given. Applicant is interviewed by at least three supervisors in the Division. All three supervisors must concur before an offer of employment is made.
Date: October 23, 1963
Creator: Martens, Frederick H. (Frederick Hilbert), 1921-2012.
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

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

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

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

Buckling Measurements : Heavy Natural Uranium Tubular Fuel Assemblies

Description: One-region buckling measurements that were made on a series of D/sub 2/O- moderated lattices of heavy uranium metal tubes in the Process Development Pile at Savannah River Laboratory are presented. The purposes of these measurements are to provide normalization points for lattice bucklings and to extend the study of natural uranium- D/sub 2/O systems. The dependence of buckiing on the moderator-to-fuel ratio is studied for two types of lattices.
Date: November 20, 1963
Creator: Dunklee, A. E. & Graves, William E. (William Ernest), 1941-
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

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

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

Advanced Designs and Special Applications for Fast Breeders

Description: The purpose of this paper is to describe a few of the suggested advanced concepts for fast breeder reactors and to compare these with the standard approach as to their potential advantage. I have attempted to estimate the economic effect of full technical success with each of the proposed concepts. The proposed concepts include: (1) single sodium system, (2) steam-cooled core concept, (3) direct cycle reactor using potassium as reactor coolant and working fluid, (4) molten plutonium-fuel alloy circulated and cooled by a jet of sodium, (5) settled-bed core, (6) molten salt concept, and (7) paste-fuel system.
Date: November 11, 1963
Creator: Hammond, R. Philip
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

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

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