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Anisotropic Elastic Scattering of Neutrons (open access)

Anisotropic Elastic Scattering of Neutrons

In an elastic collision the neutron loses part of its kinetic energy to the nucleus with both the kinetic and momentum of the system being conserved. However, for many elements the scattering is not isotropic in the center-of-mass system at the higher neutron energies. Many of the present reactor multigroup codes include anisotropic scattering at the high neutron energies, while many others assume isotropic scattering at all energies. In order to consider some of the effects of including anisotropic scatting, reference is made t the multigroup equation generally assumed for the slowing-down density.
Date: March 21, 1957
Creator: Copenhaver, C. M.
System: The UNT Digital Library
Beryllium (open access)

Beryllium

The information concerning beryllium assembled herein has been selected primarily to provide information that might be pertinent to the design of the ART. The creep-rupture data in the literature have been obtained from vacuum cast and extruded beryllium, rather than from the hot-pressed beryllium which will be used in the ART. A research program is being conducted by the Brush Beryllium Company, under contract to the Oak Ridge National Laboratory, which will eventually provide the design engineers with data on the high temperature strength properties of hot-pressed beryllium. In the interim, it will be necessary for the metallurgists and design engineers to make judicious estimates and extrapolations from the data available.
Date: March 21, 1957
Creator: Whitman, M. J.
System: The UNT Digital Library
Annual Report of the Boy Scouts of America: 1962 (open access)

Annual Report of the Boy Scouts of America: 1962

Annual report submitted by the Boy Scouts of America to Congress describing highlights from 1962, activities, finance, service organizational leadership, and other information about scouting programs.
Date: March 21, 1963
Creator: Boy Scouts of America
System: The Portal to Texas History
Erosion Experiments of Powder Compacted Uranium Dioxide Under Dynamic Steam Flow (Preliminary Report) (open access)

Erosion Experiments of Powder Compacted Uranium Dioxide Under Dynamic Steam Flow (Preliminary Report)

Experiments were carried out to determine the erosion, oxidation and dimensional characteristics of purposely defected fuel elements containing unsintered UO2 powder prepared by the swaging technique. The experiments were conducted in an out-of-reactor loop under superheat conditions of pressure, temperature, flow velocity and steam chemical composition.
Date: March 21, 1961
Creator: Spalaris, C. N.; Comprelli, F. A. & Siegler, M.
System: The UNT Digital Library
The Pilot Plant Operation of a Vertical Tube, Recirculating Dissolver for the Dissolution of Uranium Dioxide in Nitric Acid (open access)

The Pilot Plant Operation of a Vertical Tube, Recirculating Dissolver for the Dissolution of Uranium Dioxide in Nitric Acid

The need for criticality control in the proposed reprocessing of slightly enriched non-production fuels at Hanford has led to the development of a geometrically "safe", vertical tube, recirculating dissolver. A study of the nitric acid dissolution of uranium dioxide in a pilot plant dissolver of this type is reported here. The study was pointed toward the comparison of uranium dioxide dissolution rates in a batch and a recirculating dissolver and the definition of hydraulic problems associated with the recirculation of nitric acid, by air lift, technique through beds of reacting uranium dioxide.
Date: March 21, 1960
Creator: Smith, P. W.
System: The UNT Digital Library
Induction Melting of Uranium Dioxide Powder (open access)

Induction Melting of Uranium Dioxide Powder

Fused uranium dioxide has desirable characteristics for fabricating high density nuclear fuel elements by swaging. Methods of preparing dense uranium dioxide particles being investigated at HAPO include are arc fusion, and sintering and crushing of low density powder. This paper reports the results of exploratory experiments to prepare fused uranium dioxide by induction heating of low density powder in graphite crucibles.
Date: March 21, 1959
Creator: Newkirk, H. W.
System: The UNT Digital Library
Exploratory Drilling in the Nash Car Locality, White Canyon Area, San Juan County, Utah (open access)

Exploratory Drilling in the Nash Car Locality, White Canyon Area, San Juan County, Utah

Gregory described the broad geologic and geographic features of the white canyon area in the reconnaissance report on San Juan county.
Date: March 21, 1957
Creator: Oertell, E. W. & Spencer, D. F
System: The UNT Digital Library
Separation of Iron by Liquid-Liquid Column Extraction (open access)

Separation of Iron by Liquid-Liquid Column Extraction

From abstract: "Iron(III) can be separated from many elements by extraction from 6 to ͟8M hydrochloric acid. The extraction is carried out by passing the aqueous hydrochloric acid solution through a column packed with 2-octanone adsorbed onto a poly-fluorocarbon resin. Fluoride, phosphate, sulfate or citrate cause no interference. Traces if iron(III) can be separated quantitatively from large amounts of copper(II) or zinc(II); traces of titanium(IV) can be separated from large amounts of iron(III)."
Date: March 21, 1962
Creator: Fritz, James S. (James Sherwood), 1924- & Hedrick, C. E.
System: The UNT Digital Library
Radical and Molecular Reaction Mechanisms for (γ, n) Activated c11 Reactions in Liquid Cyclohexane (open access)

Radical and Molecular Reaction Mechanisms for (γ, n) Activated c11 Reactions in Liquid Cyclohexane

From abstract: "A study has been made of the yields of gaseous products labeled with C11 from the C12(γ, n) reaction in liquid cyclohexane. The effects of variations in the radiation dose and in the concentration of dissolved iodine during irradiation on the yields of these products were studied in order to elucidate the reaction mechanisms. A reaction model was developed as a method of assessing the relative importance of radical and molecular processes. The data suggest (1) that the formation of C11 labeled CH4, C2H4 + C2H6, and C3H6 involves a hot radical process while (2) the formation of C2H2 is by a molecular reaction with cyclohexane."
Date: March 21, 1962
Creator: Rack, Edward P. & Voigt, Adolf F.
System: The UNT Digital Library
αZ Correction to the Bethe-Maximon Pair Production Cross Section (open access)

αZ Correction to the Bethe-Maximon Pair Production Cross Section

From abstract: "The first order correction in αZ to the Bethe-Maximon pair production cross section is calculated for the case where the incident photon and one of the electrons has an energy much greater than mc2. Comparison of these calculations to the experimental data of Plimpton and Hammer shows an improvement ina greement between theory and experiment of approximately a factor of 1+(αZ4π/15) for low positron kinetic energies. However, for positron kinetic energies of the order of 1 Mev no improvement is obtained."
Date: March 21, 1962
Creator: Moroi, David S. & Hammer, C. L.
System: The UNT Digital Library
Electrical Properties of the Tungsten Bronzes (open access)

Electrical Properties of the Tungsten Bronzes

From abstract: "The electrical resistivity of NaxWO3, LixWO3, and KxWO3 has been measured at 300°K. The range of x-values was 0.25 < x < 0.9. All resistivities were characteristic of a metal and lie on a single curve. An extrapolation of the conductivity curve to zero conductivity indicated that the tungsten bronzes should be semiconductors for x < 0.25. The resistivities that have been measured for tungsten bronzes with x < 0.25 showed semiconducting behavior. The resistivity of LixWO3 exhibited an anomalous peak in the ρ vs Τ cuve. The Hall coefficient of Li0.37WO3 indicated one free electron per alkali atom as was previously found for NaxWO3. The Seebeck coefficient of NaxWO3 depended linearly on x[superscript]-2/3 as expected from free electron theory. The implications of these and some other data are discussed."
Date: March 21, 1962
Creator: Shanks, H. R.; Sidles, Paul Howard & Danielson, G. C.
System: The UNT Digital Library
Deposit Summary (open access)

Deposit Summary

Deposit summary of $10.00 made on March 21, 2001
Date: March 21, 2001
Creator: unknown
System: The UNT Digital Library
Data Director editor user's manual. [EDIT] (open access)

Data Director editor user's manual. [EDIT]

EDIT allows the user to edit or create text, either interactively or in the batch mode. The text may be a source program, program data, or documents. Special provisions permit the creation or editing of APT source-language programs. EDIT processes ASCII files from any accessible Data Director library and outputs files to any such library as specified by the user.
Date: March 21, 1977
Creator: McGoldrick, P.
System: The UNT Digital Library
Preliminary three-dimensional potential flow simulation of a five-liter flask air injection experiment (open access)

Preliminary three-dimensional potential flow simulation of a five-liter flask air injection experiment

The preliminary results of an unsteady three-dimensional potential flow analysis of a five-liter flask air injection experiment (small-scale model simulation of a nuclear reactor steam condensation system) are presented. The location and velocity of the free water surface in the flask as a function of time are determined during pipe venting and bubble expansion processes. The analyses were performed using an extended version of the NASA-Ames Three-Dimensional Potential Flow Analysis System (POTFAN), which uses the vortex lattice singularity method of potential flow analysis. The pressure boundary condition at the free water surface and the boundary condition along the free jet boundary near the pipe exit were ignored for the purposes of the present study. The results of the analysis indicate that large time steps can be taken without significantly reducing the accuracy of the solutions and that the assumption of inviscid flow should not have an appreciable effect on the geometry and velocity of the free water surface. In addition, the computation time required for the solutions was well within acceptable limits.
Date: March 21, 1977
Creator: Davis, J. E.
System: The UNT Digital Library
LMFBR safety. 4. Review of current issues and bibliography of literature (1974--1975) (open access)

LMFBR safety. 4. Review of current issues and bibliography of literature (1974--1975)

This report discusses the current status of liquid-metal fast breeder reactor (LMFBR) development and one of the principal safety issues, a hypothetical core-disruptive accident (HCDA). Bibliographic information on worldwide LMFBRs relative to the development of the breeder reactor as a safe source of nuclear power is presented for the period 1974 through 1975. The bibliography consists of approximately 1554 abstracts covering early research and development and operating experiences leading up to the present design practices that are necessary for the licensing of breeder reactors. Key-word, author, and permuted-title indexes are included for completeness.
Date: March 21, 1977
Creator: Buchanan, J. R. & Keilholtz, G. W.
System: The UNT Digital Library
A Parallel Multigrid Method for the Finite Element Analysis of Mechanical Contact (open access)

A Parallel Multigrid Method for the Finite Element Analysis of Mechanical Contact

A geometrical multigrid method for solving the linearized matrix equations arising from node-on-face three-dimensional finite element contact is described. The development of an efficient implementation of this combination that minimizes both the memory requirements and the computational cost requires careful construction and storage of the portion of the coarse mesh stiffness matrices that are associated with the contact stiffness on the fine mesh. The multigrid contact algorithm is parallelized in a manner suitable for distributed memory architectures: results are presented that demonstrates the scheme's scalability. The solution of a large contact problem derived from an analysis of the factory joints present in the Space Shuttle reusable solid rocket motor demonstrates the usefulness of the general approach.
Date: March 21, 2002
Creator: Hales, J. D. & Parsons, I. D.
System: The UNT Digital Library
Distortion Correction for the Many Beam Fabry Perot Velocimeter (open access)

Distortion Correction for the Many Beam Fabry Perot Velocimeter

Graphical curves and text tables are presented that map out time and space distortions for data obtained from film records of the Many Beam Fabry Perot Velocimeter. Effective distortion corrections extracted from these mappings can be applied to upcoming velocimetry experiments, but only with limited success over periods of a year or more into the future. A method of using three fiducials to provide fresh time and space distortion data on each film record is presented as a more reliable procedure to correct distortions to an acceptable level of accuracy.
Date: March 21, 2001
Creator: Avara, G.; Collins, L. & Rivera, A.
System: The UNT Digital Library
Delineation of Fast Flow Paths in Porous Media Using Noble Gas Tracers (open access)

Delineation of Fast Flow Paths in Porous Media Using Noble Gas Tracers

Isotopically enriched xenon isotopes are ideal for tracking the flow of relatively large volumes of groundwater. Dissolved noble gas tracers behave conservatively in the saturated zone, pose no health risk to drinking water supplies, and can be used with a large dynamic range. Different Xe isotopes can be used simultaneously at multiple recharge sources in a single experiment. Results from a tracer experiment at a California water district suggests that a small fraction of tracer moved from the recharge ponds through the thick, unconfined, coarse-grained alluvial aquifer to high capacity production wells at a horizontal velocity of 6 m/day. In contrast, mean water residence times indicate that the average rate of transport is 0.5 to 1 m/day.
Date: March 21, 2002
Creator: Hudson, G. B. & Moran, J. E.
System: The UNT Digital Library
IR Extinction Coefficient Measurements of CH and CD GDP Shells (open access)

IR Extinction Coefficient Measurements of CH and CD GDP Shells

None
Date: March 21, 2003
Creator: Cook, R C & Nikroo, A
System: The UNT Digital Library
Determination of /sup 232/U daughter products released from HTGR fuel during refabrication. Part 2 (open access)

Determination of /sup 232/U daughter products released from HTGR fuel during refabrication. Part 2

During the heat treatment step of High Temperature Gas-Cooled Reactor (HTGR) fuel beads, the /sup 233/U-loaded fuel beads are exposed to temperatures as high as 1700/sup 0/C. Since /sup 233/U fuel beads unavoidably contain a small percentage of /sup 232/U, decay products of /sup 232/U might be released during the heat treatment step. To avoid shielding requirements, experiments were conducted using /sup 232/Th-loaded fuel beads rather than /sup 232/U-loaded fuel beads. Decay products of /sup 232/U and /sup 232/Th are the same after /sup 228/Th. Experimental data were obtained by monitoring the 583 and 2614 keV gamma emissions of /sup 208/Tl. Computer simulations of the decay process and experimental data were used to infer what relative amount of the daughter products was removed. The carbonization step (300 to 500/sup 0/C) has an effect on the loss of daughter products in the conversion step. Using uncarbonized fuel beads, approximately 50 percent of /sup 220/Rn was removed at 300/sup 0/C and approximately 20 percent of /sup 220/Rn was removed at 200/sup 0/C. At most, 5 percent of /sup 220/Rn was removed from uncarbonized beads at 25/sup 0/C. Marginal /sup 220/Rn loss was detected at 100/sup 0/C using pre-carbonized beads. At 1400/sup 0/C, …
Date: March 21, 1975
Creator: Bencini-Tibo, L. F.; Horton, J. R. & Kelley, D. F.
System: The UNT Digital Library
Required Be Capsule Strength For Room Temperature Transport (open access)

Required Be Capsule Strength For Room Temperature Transport

The purpose of this memo is to lay out the criteria for the Be capsule strength necessary for room temperature transport. Ultimately we will test full thickness capsules by sealing high pressures inside, but currently we are limited to both thinner capsules and alternative measures of capsule material strength.
Date: March 21, 2005
Creator: Cook, B
System: The UNT Digital Library
Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005 (open access)

Ultrasonic Examination of Double-Shell Tank 241-AP-102. February 2005

COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AP-102. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-AP-102 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plan (ETP), RPP-22571 (Jensen 2004) and summarized on page 1 of this document, are reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations.
Date: March 21, 2005
Creator: Pardini, Allan F. & Posakony, Gerald J.
System: The UNT Digital Library
Total Pion Cross Section Measurements. Annual Progress Report, January 1, 1978--December 31, 1978. (open access)

Total Pion Cross Section Measurements. Annual Progress Report, January 1, 1978--December 31, 1978.

None
Date: March 21, 1979
Creator: unknown
System: The UNT Digital Library
Chemical Processing Department monthly report for February 1960 (open access)

Chemical Processing Department monthly report for February 1960

Production Pu nitrate and unfabricated Pu metal during Feb. was below forecast; however FY output is above forecast. Production of UO{sub 3} exceeded commitments; shipments met schedule. Decontamination performance of Purex solvent extraction system was subnormal. Pu nitrate solutions were concentrated. A fire occurred in Purex N Cell during conversion of ion exchange prototype to production facility.
Date: March 21, 1960
Creator: unknown
System: The UNT Digital Library