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Water Spectra and Energy Exchange Kernels

Description: Many measurement of neutron spectra have been made in water assemblies. In these system a large part of the spectrum is given by an essentially Maxwellian distribution at the moderator temperature which is insensitive to the scattering model. Hence, the test of the energy exchange scattering kernel is in the difference of the spectrum and the fundamental or Maxwellian component. The figure shows the spectrum for the Nelkin model. Once the fundamental has been subtracted neither theoretical model seems to fit the data extremely well. Below kT the Nelkin model is a closer fit than the gas model but it underestimates the deviation from the Maxwellian whereas in the joining region it overestimates the distortion.
Date: July 11, 1963
Creator: Daitch, Paul B. (Paul Bernard), 1925- & Ohanian, M. J.
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

Experimental Usefulness of the Kangaroo Rat

Description: Abstract. The kangaroo rat is readily tamed and has certain characteristics that make it unique and of interest in highly specialized research programs. Studies were conducted on its ability to exist on a dried diet with only a bare minimum of water and that obtained from succulent plants. Hematological studies indicate that the kangaroo rat exhibits a different hematological distribution of cells than the mouse or rat. The lymphocyte constitutes 81.4% of the total leuokocytes. The hematocrit has a value of 46 to 48 in spite of the high degree of water conservation practiced by the animal. The response to ionizing radiation of this species does not differ from that reported for the mouse or rat. Behavior studies indicate that the digging characteristics of the kangaroo rat are similar to those of the gerbil. Furthermore, the animal shows definite psychotic tendencies under the influence of psychotomimetics like LSD-25 and psilocybin. An evaluation of the physiological responses of isolated tissues from this animal as well as its responses to anesthetics is being undertaken to evaluate its further usefulness in the laboratory.
Date: September 13, 1963
Creator: Haley, Thomas J.
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

An Electrochemical pH-STAT

Description: An apparatus has been developed which controls automatically the acidity of unbuffered solutions in the region from pH 4 to 10. A potentiostat is used to control the potential of an inert electrode on which the hydrogen gas-hydrogen ion reaction occurs in a solution saturated with hydrogen gas. The inert electrode acts as both a sensing element and a regulating electrode for the control of acidity. Current from the potentiostat passes through the inert electrode and an auxiliary polarizing electrode in an external compartment separated from the main cell by a salt bridge or porous plate. Transients which occur during the regulating action are presented and analyzed. The electrochemical pH-stat may be used to measure corrosion rates. Limitations of the device are discussed and a modification is proposed which makes use of a differential amplifier instead of a potentiostat.
Date: October 1963
Creator: Posey, F. A. (Franz Adrian), 1930-; Morozumi, T. & Kelly, E. J.
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

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

Staffing Experience for Operation of the Plutonium Recycle Test Reactor

Description: The Plutonium Recycle Test Reactor is a research and development tool supporting the Plutonium Recycle Program and the research activities at Hanford. The present organization directly associated with the PRTR is composed of Operating, Technical Assistance, Maintenance, and Engineering Groups. Liaison with research groups utilizing PRTR facilities is accomplished through the Technical Assistance Group. the other three groups serve the PRTR in the manner suggest by the group name. This paper limits its interest to the staffing experience of the Operating Group.
Date: September 23, 1963
Creator: Koberg, D. R.
Partner: UNT Libraries Government Documents Department

Operating and Safety Problems in a Research Reactor

Description: Abstract. The purpose of this paper is to present, in the light of 20 years of reactor-operation experience at ORNL, what is being done in preparation for operation of the HFIR (High Flux Isotope Reactor). This paper considers only the areas of staffing and training; development of operating and maintenance procedures; preoperational testing of water systems; and testing of remote handling tools. The preparatory work in other areas such as the hydraulic tests, neutron tests, etc., is not covered in this presentation.
Date: October 23, 1963
Creator: McCord, R. V.
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

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

A System for Measurement of Wall Thickness of Corroded Aluminum Reactor Process Tubes

Description: A sector gauge was developed for routine measurement and recording of wall thicknesses between the ribs and at the top of installed aluminum reactor power tubes. The basic criteria selected for the device were that it would measure and record wall thickness over the length of the tube with an accuracy of plus or minus 2 mils at an average rate of 3 min per tube. An eddy-current measuring system was used in the device.
Date: October 1963
Creator: Dulin, Ralph V.
Partner: UNT Libraries Government Documents Department

ML-1 Power Determination

Description: The ML-1 is a nuclearly heated, electrical power producing plant being developed for the U. S. atomic Energy commission and the U. S. Army by Aeroject-General Nucleonics. The power plant is a compact, water-moderated, gas-cooled, nuclear reactor, coupled in a single closed cycle to a gas driven turbine-compressor set and alternator. The plant is designed to produce power up to 500 Kw electrical,using 3 Mw thermal supplied by the reactor. It will operate 10,000 hours without refueling and have a plant life of five years. The total weight is less than 40 tons and no single package weighs more than 15 tons.
Date: October 23, 1963
Creator: Lightle, Robert E.
Partner: UNT Libraries Government Documents Department

Bovine Thyroid I 131 in the Absence of Atmospheric Nuclear Weapons Tests

Description: Summary. Cattle in Reno, Nevada, exhibit a constant very low concentration of I 131 in their thyroid glands in the absence of known releases of I 131 to the atmosphere. This concentration is about 1 picocurie per gram of fresh thyroid tissue. ; This I 131 appears to originate below the tropopause
Date: 1962
Creator: Blincoe, Clifton & Bohman, V. R.
Partner: UNT Libraries Government Documents Department

Reactivity Control Problems in the Plutonium-Fueled EBR-1 Reactor

Description: In contrast with previous EBR-1 reactor cores which were fueled with enriched uranium, the current Mark IV core is a 7 x 8-in. cylinder made of delta-stabilized plutonium alloyed with 1 1/4 w/o aluminum. The reactivity of the reactor is largely controlled by the movement of the entire outer blanket mounted on a hydraulic elevator with a travel of 80 inches. Partial meltdown occurred in November, 1955 during the last experiment scheduled for the core which was directed toward identifying the time constants associated with the components of the over-all reactivity coefficients. The incident is reported elsewhere. The changes in reactivity apparently come about as a result of changing from operation on the high temperature system to the low temperature system or vice versa. Continuous operation from day to day on either system does not effect any significant change in reactivity. Reactivity is not dependent on the duration of a run, but rather on the maximum power attained during that run.
Date: October 1963
Creator: Haroldsen, R. O. (Ray Ottley), 1928-; McGinnis, F. D. & Smith, R. R.
Partner: UNT Libraries Government Documents Department

Training of Consumers Public Power District Personnel for the Operation of the Hallam Nuclear Power Facility

Description: Training of Consumers Public Power District (CPPD) operating personnel for the Hallam Nuclear Power Facility (HNPF) was carried out under two formalized training programs. Both programs were organized and directed by Atomics International (AI). The first program was conducted in 1960 while he HNPF was under construction. The second program was begun in September 1961, prior to the initial HNPF dry critical loading experiment, and was completed in February 1963. The conventional portion of Sheldon Station has been a commercial power plant since July 1, 1961. Sheldon Station CPPD personnel were utilized extensively as instructors for the two formalized HNPF training programs and as responsible engineers for numerous test of the HNPF. CPPD shift personnel constituted the principal operating force throughout HNPF construction, reactor startup, and testing.
Date: October 1963
Creator: Loomis, J. S.
Partner: UNT Libraries Government Documents Department

A Cladding Failure Monitor for Liquid Metal-Cooled Reactor Systems

Description: A cladding failure monitor using the principle of detection of rare gas fission products in the cover gas system of liquid metal-cooled reactors, was developed which efficiently discriminates against AR41. This discrimination is accomplished by electrostatic precipitation of the rare gas daughter nuclides; since K41, the daughter of Ar41, is not radioactive, the activity of the precipitation is chiefly due to decay of various Rb and Cs fission products. The monitor equipment is described. Results of monitor testing in EBR-1 are reported; a simulated fuel road failure experiment was made which shows that the charged-wire cover gas monitoring principle should be useful in other sodium-cooled fast reactors systems.
Date: October 1963
Creator: Smith, R. R. & Doe, B. B.
Partner: UNT Libraries Government Documents Department

Detection and Identification of a Ruptured Fuel Element at the SM-1 (APR-1) Nuclear Power Plant

Description: Summary. In October 1960, increases in the fission product activity of the primary coolant of the SM-1 power plant indicated that a fuel element failure had occurred. Low power tests were run first to determine the nature and magnitude of the defect. Flux tilting experiments were then performed to determine the general location of the failed element. Finally, the primary coolant flowing through each of the fuel elements was sampled at low reactor power for relative iodine activity to determine the exact location of the defective element.. The element was found and replaced. Upon return to power, the fission product activity dropped back to its normal full power value.
Date: 1961
Creator: Misenheimer, Leo J.; Purple, Robert A. & Brown, Paul S.
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

Approximate Models for Distributed-Parameter Heat-Transfer Systems

Description: Summary: The use of dimensionless-parameter frequency response diagrams to determine accuracies of lumped-parameter approximations is demonstrated by two examples: calculation of the heat flux at the surface of a semi-infinite solid due to temperature fluctuations of an adjacent fluid; and the response of a counterflow heat exchanger to inlet fluid temperature perturbations. Dimensionless system parameters make it possible to use general-purpose plots to find the error in particular approximations as a function of the frequency of perturbation. Such plots are directly applicable to control-system stability problems, where the highest frequency of interest is usually apparent.
Date: August 20, 1963
Creator: Ball, S. J.
Partner: UNT Libraries Government Documents Department

Electronic Data Processing an Application to Nuclear Materials Management

Description: Abstract: This report is concerned with the application of an electronic data processing system to the unique combination of scientific and commercial data processing requirement of nuclear materials management. The organization and flow of data from the plant through the data processing equipment to the final report is the principle topic of the report. Included in the discussion, however, are topics concerned with the impact of conversion to electronic data processing on personnel, materials management costs, and on other plant organizations. Portions of the report are devoted to programming systems and decision-making abilities of data processing equipment which make these systems readily adaptable to nuclear materials management.
Date: 1963
Creator: Hudson, J. F.
Partner: UNT Libraries Government Documents Department

Removal of Radioisotopes From Solution by Earth Materials From Eastern Idaho

Description: Abstract: Naturally occurring earth materials from Idaho, primarily from localities near the National Reactor Testing Station (NRTS), were used in laboratory tests for the removal of radioisotopes from aqueous solutions. These earth materials included lignitic deposits, clay-like materials, and specific minerals; ion exchange resins were also considered for a specific application. The aqueous solutions were low-level radioactive cooling water or synthetic solutions made up to represent low-level radioactive wastes at the NRTS. Cation exchange capacities and other properties which affect the removal of radioisotopes from solution were determined the cation exchange capacities varied from 0.006 to 1.0 meq/g of solid. Earth materials with cation exchange capacities greater than 0.3 meq/g, in general, had distribution coefficients in excess of 1000. The highest distribution coefficients for cesium and strontium occurred in the pH range from 6.0 to 9.0 The possible use of these materials for decontaminating low-level radioactive waste at the NRTS is discussed. The result of laboratory studies using these materials and an organic ion exchange resign for decontaminating a specific NRTS waste are given. A material high in clinoptilolite from a location near the NRTS was considered to be the most promising material for use in large beds or ion exchange-type columns.
Date: April 1964
Creator: Wilding, M. W. & Rhodes, D. W. (Donald Walter), 1919-
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