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Quantum chromodynamics in few-nucleon systems (open access)

Quantum chromodynamics in few-nucleon systems

One of the most important implications of quantum chromodynamics (QCD) is that nuclear systems and forces can be described at a fundamental level. The theory provides natural explanations for the basic features of hadronic physics: the meson and baryon spectra, quark statistics, the structure of the weak and electromagnetic currents of hadrons, the scale-invariance of hadronic interactions at short distances, and evidently, color (i.e., quark and gluon) confinement at large distances. Many different and diverse tests have confirmed the basic predictions of QCD; however, since tests of quark and gluon interactions must be done within the confines of hadrons there have been few truly quantitative checks. Nevertheless, it appears likely that QCD is the fundamental theory of hadronic and nuclear interactions in the same sense that QED gives a precise description of electrodynamic interctions. Topics discussed include exclusive processes in QCD, the deuteron in QCD, reduced nuclear amplitudes, and limitations of traditional nuclear physics. 32 references. (WHK)
Date: October 1, 1983
Creator: Brodsky, Stanley J.
Object Type: Article
System: The UNT Digital Library
Initial TMX-U thermal-barrier experiments (open access)

Initial TMX-U thermal-barrier experiments

This paper describes results from the initial thermal barrier experiments in the Tandem Mirror Experiment-Upgrade (TMX-U). Strong end plugging has been produced using a combination of ECRH gyrotrons with sloshing ion beam injection. Plugging has been achieved with a central cell higher than that of the end plugs. In these low-density central cell experiments (7 x 10/sup 11/ cm/sup -3/) the axial losses (tau/sub parallel to/ = 20 to 80 ms) are smaller than the radial losses (tau/sub perpendicular to/ = 4 to 8 ms). Although no direct measurements are yet available to determine if a thermal barrier potential dip is generated, these experiments support many theoretical features of the thermal barrier concept.
Date: October 5, 1983
Creator: Simonen, T. C.; Allen, S. L.; Berzins, L.; Carter, M.; Casper, T. A.; Clauser, J. F. et al.
Object Type: Report
System: The UNT Digital Library
Fracture behavior of zircaloy spent-fuel cladding (open access)

Fracture behavior of zircaloy spent-fuel cladding

The Zircaloy cladding of water reactor fuel rods is susceptible to local breach-type failure, commonly known as pellet-cladding interaction (PCI) failure, during operational and off-normal power transients after the fuel has achieved a sufficiently high burnup. An optimization of power ramp procedures or fuel rod fabrication to minimize the cladding failure would result in a significant decrease in radiation exposure of plant personnel due to background and airborne radioactivity as well as an extension of core life in terms of allowable off-gas radioactivity. As part of a program to provide a better understanding of the fuel rod faiure phenomenon and to facilitate the formulation of a better failure criterion, a mechanistic study of the deformation and fracture behavior of high-burnup spent-fuel cladding is in progress under simulated PCI conditions.
Date: October 1, 1983
Creator: Chung, H.M.; Yaggee, F.L. & Kassner, T.F.
Object Type: Article
System: The UNT Digital Library
Non-reactor neutron irradiation facility: the Argonne Intense Pulsed Neutron Source (open access)

Non-reactor neutron irradiation facility: the Argonne Intense Pulsed Neutron Source

A new generation of neutron sources is just coming into existence with great promise for the future. These sources are based on neutron production by spallation from the interaction of high energy protons with a heavy metal target. Currently the highest flux facility of this type is the Intense Pulsed Neutron Source at Argonne National Laboratory. This machine is also unique in its dedication to both slow-neutron scattering and fast-neutron damage studies.
Date: October 1, 1983
Creator: Birtcher, R. C. & Scott, T. L.
Object Type: Article
System: The UNT Digital Library
Review of the experimental papers at the IAEA conference on noninductive current drive, Culham, 1983 (open access)

Review of the experimental papers at the IAEA conference on noninductive current drive, Culham, 1983

Three types of noninductive current drive experiments have been reported at this conference: (1) neutral beam (2) rf current drive, and (3) relativistic electron beams (REB). If we compare the effort to develop current drive to a horse race, the neutral beam horse was first out of the gates, but it quickly found greener pastures (heating) and has dropped temporarily out of the race. The lower hybrid horse now has a big lead at the first furlong (200 m), but the bulk of the race remains to be run. The fast wave and REB horses have yet to get up speed.
Date: October 1, 1983
Creator: Motley, R. W.
Object Type: Report
System: The UNT Digital Library
Maximum likelihood estimation for cytogenetic dose-response curves (open access)

Maximum likelihood estimation for cytogenetic dose-response curves

In vitro dose-response curves are used to describe the relation between the yield of dicentric chromosome aberrations and radiation dose for human lymphocytes. The dicentric yields follow the Poisson distribution, and the expected yield depends on both the magnitude and the temporal distribution of the dose for low LET radiation. A general dose-response model that describes this relation has been obtained by Kellerer and Rossi using the theory of dual radiation action. The yield of elementary lesions is kappa(..gamma..d + g(t, tau)d/sup 2/), where t is the time and d is dose. The coefficient of the d/sup 2/ term is determined by the recovery function and the temporal mode of irradiation. Two special cases of practical interest are split-dose and continuous exposure experiments, and the resulting models are intrinsically nonlinear in the parameters. A general purpose maximum likelihood estimation procedure is described and illustrated with numerical examples from both experimental designs. Poisson regression analysis is used for estimation, hypothesis testing, and regression diagnostics. Results are discussed in the context of exposure assessment procedures for both acute and chronic human radiation exposure.
Date: October 1, 1983
Creator: Frome, E.L & DuFrain, R.J.
Object Type: Report
System: The UNT Digital Library
Neutral transport in the ALT-I limiter (open access)

Neutral transport in the ALT-I limiter

The behavior of neutral atoms and molecules in the TEXTOR pump limiter ALT-I has been investigated with the aid of the 2-D Monte Carlo neutral transport code DEGAS. The code incorporates the full set of relevant collision processes (atomic and molecular), and it has a standard wall model which includes fast-neutral reflection and molecular desorption. The limiter was modeled with a 2-D geometry, which included corrections for 3-D effects. Among the quantities predicted by the code which are directly relevant to experiment include the neutral pressure within the plenum and along the duct leading into the plenum, the gettering rates, and the heat flux to the walls of the duct. These have been calculated for a variety of plasma parameters in the inlet, and the behavior with respect to variations of the duct widths has been studied. Because of the presence of the long duct separating the entrance chamber from the plenum, a high probability of ionization generally results, suggesting that a calculation allowing the plasma to adjust to the neutral sources might show a large amount of recycling.
Date: October 1, 1983
Creator: Boley, C. D.; Heifetz, D. B.; Post, D. E. & Malinowski, M. E.
Object Type: Report
System: The UNT Digital Library
Granular flow considerations in the design of a cascade solid breeder reaction chamber (open access)

Granular flow considerations in the design of a cascade solid breeder reaction chamber

Both horizontally and vertically oriented rotating chambers with granular material held on the inner surface by centrifugal action are examined. Modifications to the condition for controlled quasi-static flow on an incline plane, phi/sub w/ < ..cap alpha.. < phi/sub r/, where phi/sub w/ is the wall friction angle, ..cap alpha.. is the angle of inclination of the plane, and phi/sub r/ is the drained angle of repose of the material are examined for the case of horizontal and vertical surfaces of revolution. Allowed included half angles for horizontally oriented chambers are likely to be in the range of 30/sup 0/ +- 10/sup 0/ for ceramic particles and metal surfaces. For vertical orientations the maximum half-angle of the top cone is slightly less than the wall friction angle phi/sub w/ while the lower portion can have a half angle as large as (90/sup 0/ - phi/sub w). Percolation of fines through shearing granular solids is briefly discussed and recommended experimental and calculational studies to obtain a better understanding of this behavior are described.
Date: October 1, 1983
Creator: Walton, O.R.
Object Type: Report
System: The UNT Digital Library
Fracture behavior of high-burnup spent-fuel cladding (open access)

Fracture behavior of high-burnup spent-fuel cladding

PCI-like, brittle-type failures, characterized by pseudocleavage-plus-fluting features in the fracture surface, branching cracks, and small diametral strain, were observed to occur at 292 to 325/sup 0/C in some batches of spent power-reactor fuel-cladding tubes under internal gas-pressurization and expanding-mandrel loading conditions in which the tests were not influenced by fission product simulants. Fractographic characteristics per se do not provide evidence for a PCI failure mechanism but should be deemed only as cooroborative in nature. Evaluation of TEM thin-foil specimens, obtained from regions adjacent to the brittle-type fracture sites, characteristically revealed extensive amounts of Zr/sub 3/O precipitates and a lack of slip dislocations. The precipitation of the Zr/sub 3/O phase appears to be enhanced by a high density of irradiation-induced defects. The brittle-type failure produced in the spent-fuel cladding tubes appears to be associated with segregation of oxygen to dislocation substructures and irradiation-induced defects, which leads to the formation of an ordered zirconium-oxygen phase of Zr/sub 3/O, an immobilization of dislocations, and minimal plastic deformation in the cladding material.
Date: October 1, 1983
Creator: Chung, H.M.; Yaggee, F.L. & Kassner, T.F.
Object Type: Article
System: The UNT Digital Library
Unconventional petroleum: a current awareness bulletin (open access)

Unconventional petroleum: a current awareness bulletin

The summaries in this bulletin cover both secondary and tertiary recovery of petroleum and the following topics under Oil Shales and Tar Sands: reserves and exploration; site geology and hydrology; drilling, fracturing, and mining; oil production, recovery, and refining; properties and composition; direct uses and by-products; health and safety; marketing and economics; waste research and management; environmental aspects; and regulations. These summaries and older citations to information on petroleum, oil shales, and tar sands back to the 1960's are available for on-line searching and retrieval on the Energy Data Base using the DOE/RECON system or commercial on-line retrieval systems. Retrospective searches can be made on any aspect of petroleum, oil shales, or tar sands, or customized profiles can be developed to provide current information for each user's needs.
Date: October 30, 1983
Creator: Grissom, M.C. (ed.)
Object Type: Report
System: The UNT Digital Library
PUREX environmental radiological surveillance - preoperational and operational support program conducted by Pacific Northwest Laboratory (open access)

PUREX environmental radiological surveillance - preoperational and operational support program conducted by Pacific Northwest Laboratory

This report describes the radiological environmental sampling program that is being conducted at the US Department of Energy's (DOE) Hanford Site in support of resumed operation of the PUREX fuel processing plant. The report also summarizes preoperational radiological environmental data collected to date. The activities described herein are part of the ongoing Hanford Environmental Surveillance Program, operated by the Pacific Northwest Laboratory (PNL) for the DOE.
Date: October 1, 1983
Creator: Sula, M. J. & Price, K. R.
Object Type: Report
System: The UNT Digital Library
Evaluation of stainless steel pipe cracking: causes and fixes (open access)

Evaluation of stainless steel pipe cracking: causes and fixes

Leaks and cracks in the heat-affected zones of weldments in austenitic stainless steel piping and associated components of boiling water reactors (BWRs) have been observed since the mid-1960s. Since that time, cracking has continued to occur and indications have been found in all parts of the recirculation system, including the largest diameter lines. Proposed solutions include remedies primarily intended to produce a more favorable residual stress state, materials which are more resistant to stress corrosion cracking (SCC), and changes in the reactor environment which decrease the susceptibility to cracking. In addition to evaluating these remedies, it is also important to gain a better understanding of key variables such as residual stresses, crack growth rates, and the leak-before-break margin in flawed piping, which may impact regulatory decisions on operating plants. The main areas of effort during the past year have been (1) studies of impurity effects on susceptibility to intergranular stress corrosion cracking (IGSCC), (2) crack growth rate measurements, (3) finite-element studies of residual stress produced by induction heating stress improvement (IHSI) and the addition of weld overlays to flawed piping, (4) leak-before-break analyses of piping with 360/sup 0/ part-through cracks, and (5) parametric studies on the effect of through-wall residual …
Date: October 1, 1983
Creator: Shack, W. J.; Kassner, T. F.; Maiya, P. S.; Nichols, F. A.; Park, J. Y.; Ruther, W. et al.
Object Type: Report
System: The UNT Digital Library
Acoustic imaging of vapor bubbles through optically non-transparent media (open access)

Acoustic imaging of vapor bubbles through optically non-transparent media

A preliminary investigation of the feasibility of acoustic imaging of vapor bubbles through optically nontransparent media is described. Measurements are reported showing the echo signals produced by air filled glass spheres of various sizes positioned in an aqueous medium as well as signals produced by actual vapor bubbles within a water filled steel pipe. In addition, the influence of the metallic wall thickness and material on the amplitude of the echo signals is investigated. Finally several examples are given of the imaging of spherical bubbles within metallic pipes using a simulated array of acoustic transducers mounted circumferentially around the pipe. The measurement procedures and a description of the measuring system are also given.
Date: October 1, 1983
Creator: Kolbe, W.F.; Turko, B.T. & Leskovar, B.
Object Type: Article
System: The UNT Digital Library
Littoral processes: US Coast Guard Station, Fort Point, San Francisco (open access)

Littoral processes: US Coast Guard Station, Fort Point, San Francisco

The US Coast Guard Station, Fort Point is located three-quarters of a nautical mile southeast of the Golden Gate Strait, the entrance to San Francisco Bay. The existing storm wave conditions at Fort Point Station pier make it extremely dangerous for the SAR crews to get on and off the Motor Life Boats at times requiring the vessels to be moored at the San Francisco Yacht Harbor about 1.5 miles east of the Fort Point Station. To mitigate these harsh working conditions the US Coast Guard is considering the feasibility of constructing suitable all-weather moorings for the three Motor Life Boats at the Fort Point Station to enable unimpeded SAR operations, to provide safe working conditions for Coast Guard small boat crews, and to improve small boat maintenance conditions at Fort Point Station. The purpose of this report is to identify, analyze and evaluate physical environmental factors that could affect all-weather moorings siting, configuration and entrance location, as well as potential post construction alterations to littoral conditions and processes. This report includes a description of the site, description of pertinent littoral processes, evaluation of how these processes could affect construction of all-weather moorings, and discussion of design considerations, as well …
Date: October 1, 1983
Creator: Ecker, R.M. & Whelan, G.
Object Type: Report
System: The UNT Digital Library
Response to W. W. Kellogg carbon dioxide and climatic change: implications for mankind's future (open access)

Response to W. W. Kellogg carbon dioxide and climatic change: implications for mankind's future

The writer objects to the consensus that doubled CO/sub 2/ levels will lead to a global temperature increase of 3/sup 0/C and the associated implications for mankind. In this paper he presents his reasons for doubting the majority view on two climatic feedback processes: (1) the ice-albedo feedback, and (2) the water vapor feedback. (ACR)
Date: October 1, 1983
Creator: Ellsaesser, H.W.
Object Type: Article
System: The UNT Digital Library
Universality of the topology of period doubling dynamical systems (open access)

Universality of the topology of period doubling dynamical systems

The evolution of the topology of the invariant manifolds of the attractors of 3-D autonomous dynamical systems during period doubling is shown to be universal. The overall topology of the nth attractor is shown to depend only on the topology of the first attractor at birth.
Date: October 1, 1983
Creator: Beiersdorfer, P.
Object Type: Report
System: The UNT Digital Library
Chiral anomalies and differential geometry (open access)

Chiral anomalies and differential geometry

Some properties of chiral anomalies are described from a geometric point of view. Topics include chiral anomalies and differential forms, transformation properties of the anomalies, identification and use of the anomalies, and normalization of the anomalies. 22 references. (WHK)
Date: October 1, 1983
Creator: Zumino, B.
Object Type: Article
System: The UNT Digital Library
Aging degradation of cast stainless steel: status and program (open access)

Aging degradation of cast stainless steel: status and program

A program has been initiated to investigate the significance of in-service embrittlement of cast duplex stainless steels under light-water reactor operating conditions. The existing data are reviewed to determine the critical parameters that control the aging behavior and to define the objectives and scope of the investigation. The test matrices for microstructural studies and mechanical property measurements are presented. The initial experimental effort is focussed on characterizing the microstructure of long-term, low-temperature aged material. Specimens from three heats of cast CF-8 and CF-8M stainless steel aged for up to 70,000 h at 300, 350, and 400/sup 0/C were obtained from George Fisher Ltd., of Switzerland. Initial analyses reveal the formation of three different types of precipitates which are not ..cap alpha..'. An FCC phase, similar to the M/sub 23/C/sub 6/ precipitates, was present in all the long-term aged material. 15 references, 10 figures, 2 tables.
Date: October 1, 1983
Creator: Chopra, O. K. & Ayrault, G.
Object Type: Report
System: The UNT Digital Library
Analysis/plot generation code with significance levels computed using Kolmogorov-Smirnov statistics valid for both large and small samples (open access)

Analysis/plot generation code with significance levels computed using Kolmogorov-Smirnov statistics valid for both large and small samples

This report describes a version of the TERPED/P computer code that is very useful for small data sets. A new algorithm for determining the Kolmogorov-Smirnov (KS) statistics is used to extend program applicability. The TERPED/P code facilitates the analysis of experimental data and assists the user in determining its probability distribution function. Graphical and numerical tests are performed interactively in accordance with the user's assumption of normally or log-normally distributed data. Statistical analysis options include computation of the chi-square statistic and the KS one-sample test statistic and the corresponding significance levels. Cumulative probability plots of the user's data are generated either via a local graphics terminal, a local line printer or character-oriented terminal, or a remote high-resolution graphics device such as the FR80 film plotter or the Calcomp paper plotter. Several useful computer methodologies suffer from limitations of their implementations of the KS nonparametric test. This test is one of the more powerful analysis tools for examining the validity of an assumption about the probability distribution of a set of data. KS algorithms are found in other analysis codes, including the Statistical Analysis Subroutine (SAS) package and earlier versions of TERPED. The inability of these algorithms to generate significance levels …
Date: October 1, 1983
Creator: Kurtz, S.E. & Fields, D.E.
Object Type: Report
System: The UNT Digital Library
Current status of the FASTGRASS/PARAGRASS models for fission product release from LWR fuel during normal and accident conditions (open access)

Current status of the FASTGRASS/PARAGRASS models for fission product release from LWR fuel during normal and accident conditions

The theoretical FASTGRASS model for the prediction of the behavior of the gaseous and volatile fission products in nuclear fuels under normal and transient conditions has undergone substantial improvements. The major improvements have been in the atomistic and bubble diffusive flow models, in the models for the behavior of gas bubbles on grain surfaces, and in the models for the behavior of the volatile fission products iodine and cesium. The thoery has received extensive verification over a wide range of fuel operating conditions, and can be regarded as a state-of-the-art model based on our current level of understanding of fission product behavior. PARAGRASS is an extremely efficient, mechanistic computer code with the capability of modeling steady-state and transient fission-product behavior. The models in PARAGRASS are based on the more detailed ones in FASTGRASS. PARAGRASS updates for the FRAPCON (PNL), FRAP-T (INEL), and SCDAP (INEL) codes have recently been completed and implemented. Results from an extensive FASTGRASS verification are presented and discussed for steady-state and transient conditions. In addition, FASTGRASS predictions for fission product release rate constants are compared with those in NUREG-0772. 21 references, 13 figures.
Date: October 1, 1983
Creator: Rest, J.; Zawadski, S.A. & Piasecka, M.
Object Type: Article
System: The UNT Digital Library
Energy and technology review (open access)

Energy and technology review

Three review articles are presented. The first describes the Lawrence Livermore Laboratory role in the research and development of oil-shale retorting technology through its studies of the relevant chemical and physical processes, mathematical models, and new retorting concepts. Second is a discussion of investigation of properties of dense molecular fluids at high pressures and temperatures to improve understanding of high-explosive behavior, giant-planet structure, and hydrodynamic shock interactions. Third, by totally computerizing the triple-quadrupole mass spectrometer system, the laboratory has produced a general-purpose instrument of unrivaled speed, selectivity, and adaptability for the analysis and identification of trace organic constituents in complex chemical mixtures. (GHT)
Date: October 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Imperial County geothermal development quarterly report, July 1-September 30, 1983 (open access)

Imperial County geothermal development quarterly report, July 1-September 30, 1983

The highlights of geothermal development in Imperial County during July, August, and September 1983 are discussed. Topics include the status of geothermal development projects in the county, geothermal staff activities and research projects, and other geothermal-related topics.
Date: October 1, 1983
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Cytometric analysis of shape and DNA content in mammalian sperm (open access)

Cytometric analysis of shape and DNA content in mammalian sperm

Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. Sperm were analyzed by flow cytometry and slit-scan flow analysis for injury following the exposure of testes to mutagens. The utility of flow cytometry in genotoxin screening and monitoring of occupational exposure was evaluated. The technique proved valuable in separation of X- and Y-chromosome bearing sperm and the potential applicability of this technique in artificial insemination and a solution, of accurately assessing the DNA content of sperm were evaluated-with reference to determination of X- and Y-chromosome bearing sperm.
Date: October 10, 1983
Creator: Gledhill, B.L.
Object Type: Article
System: The UNT Digital Library
Normal-zone detectors for the MFTF-B coils. Revision 1 (open access)

Normal-zone detectors for the MFTF-B coils. Revision 1

In order to protect a set of inductively coupled superconducting magnets, it is necessary to locate and measure normal zone voltages that are small compared with the mutual and self-induced voltages. The method described in this report uses two sets of voltage measurements to locate and measure one or more normal zones in any number of coupled coils. One set of voltages is the outputs of bridges that balance out the self-induced voltages. The other set of voltages can be the voltages across the coils, although alternatives are possible. The two sets of equations form a single combined set of equations. Each normal zone location or combination of normal zones has a set of these combined equations associated with it. It is demonstrated that the normal zone can be located and the correct set chosen, allowing determination of the size of the normal zone. Only a few operations take place in a working detector: multiplication of a constant, addition, and simple decision-making. In many cases the detector for each coil, although weakly linked to the other detectors, can be considered to be independent. An example of the detector design is given for four coils with realistic parameters. The effect on …
Date: October 10, 1983
Creator: Owen, E. W. & Shimer, D. W.
Object Type: Report
System: The UNT Digital Library