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A Design Method for Multiple Tube Gas-Cooled Electrical Leads forthe g-2 Superconducting Magnets (open access)

A Design Method for Multiple Tube Gas-Cooled Electrical Leads forthe g-2 Superconducting Magnets

None
Date: December 15, 1994
Creator: Green, M. A.; Jia, L. X.; Addessi, L. J.; Cullen, J. R.; Esper, A. J. & and Meier, R. E.
System: The UNT Digital Library
[The North Texan, Vol. 44 No. 4, December 1994] (open access)

[The North Texan, Vol. 44 No. 4, December 1994]

A clipping from The North Texan, Vol. 44 No. 4, of an article written by Cass Brunner. The focus of the piece is Dr. R. William McCarter and his time at UNT. He is the recipient of the 1994 Higher Education Art Educator of the Year, given by the Texas Art Education Association.
Date: December 1994
Creator: Brunner, Cass
System: The UNT Digital Library
[The Dallas Morning News, December 25, 1994] (open access)

[The Dallas Morning News, December 25, 1994]

An article in The Dallas Morning News that was written by Shermakaye Bass that discusses different university programs and art groups. The UNT NTIEVA and Dallas Museum of Art pairing is one of the featured groups.
Date: December 25, 1994
Creator: Bass, Shermakaye
System: The UNT Digital Library
Disilene Addition to C{sub 70} (open access)

Disilene Addition to C{sub 70}

Semiempirical and ab initio Hartree Fock computational results indicate that the highly reactive dienophile tetramethyldisilene, Me{sub 2}Si=SiMe{sub 2}, is an excellent candidate for a novel functionalization of the equator of C{sub 70} via a [2+4] cycloaddition to the 21, 22, 23, 42 carbons. Thermal or photochemical generation of tetramethyldisilene in the presence of C{sub 70} results in similar complex mixtures in which the major product appears to be that of [2+2] cycloaddition to the 7,8 carbons of C{sub 70}. A minor product clearly results from [2+2] cycloaddition to the 1,9 carbons. Both of these products are hydrolytically unstable and are converted nonspecifically to mixtures of 1,9- and 7,8-C{sub 70}H{sub 2} which are also present in HPLC traces of the reaction mixtures.
Date: December 31, 1994
Creator: Jacobs, S. J.; Cahill, P. A. & Rohlfing, C. M.
System: The UNT Digital Library
B-Physics results from D0 (open access)

B-Physics results from D0

We report on preliminary measurements of the inclusive single muon and dimuon cross sections in p{bar p} collisions at {radical}s = 1.8 TeV using the D0 detector at the Fermilab collider. From these results, we extract the cross section for b-quark production for the kinematic range {vert_bar}yb{vert_bar} < 1.0 and 6 < p{sub t}{sup b} < 50 GeV/c. We also report measurements on the J/{psi} production, and correlations between muons in dimuon events.
Date: December 1, 1994
Creator: Hedin, D. & Markosky, L.
System: The UNT Digital Library
Flat panel display development activities at Sandia National Laboratories (open access)

Flat panel display development activities at Sandia National Laboratories

The flat panel display development activities underway at Sandia National Laboratories are described. Research is being conducted in the areas of glass substrates, phosphors, large area processes, and electron emissions. Projects are focused on improving process yield, developing large area processes, and using modeling techniques to predict design performance.
Date: December 31, 1994
Creator: DiBello, E. G.; Worobey, W.; Burchett, S.; Hareland, W.; Felter, T. & Mays, B.
System: The UNT Digital Library
The role of the LLNL Atmospheric Release Advisory Capability in a FRMAC response to a nuclear power plant incident (open access)

The role of the LLNL Atmospheric Release Advisory Capability in a FRMAC response to a nuclear power plant incident

The Federal Radiological Emergency Response Plan (FRERP) can provide several emergency response resources in response to a nuclear power plant (NPP) accident if requested by a state or local agency. The primary FRERP technical resources come from the US Department of Energy`s (DOE) Federal Radiological Monitoring and Assessment Center (FRMAC). Most of the FRMAC assets are located at the DOE Remote Sensing Laboratory (RSL) at Nellis Air Force Base, Las Vegas, Nevada. In addition, the primary atmospheric dispersion modeling and dose assessment asset, the Atmospheric Release Advisory Capability (ARAC) is located at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. In the early stages of a response, ARAC relies on its automatic worldwide meteorological data acquisition via the Air Force Global Weather Center (AFGWC). The regional airport data are supplemented with data from on-site towers and sodars and the National Oceanographic & Atmospheric Administration`s (NOAA) field-deployable real-time rawinsonde system. ARAC is prepared with three-dimensional regional-scale diagnostic dispersion model to simulate the complex mixed fission product release from a reactor accident. The program has been operational for 18 years and is presently developing its third generation system. The current modernization includes faster central computers, a new site workstation system. The current …
Date: December 31, 1994
Creator: Baskett, R. L.; Sullivan, T. J.; Ellis, J. S. & Foster, C. S.
System: The UNT Digital Library
Study of parity and time reversal violation in neutron-nucleus interactions (open access)

Study of parity and time reversal violation in neutron-nucleus interactions

The parity and time-reversal symmetries can be studies in neutron-nucleus interactions. Parity non-conserving asymmetries have been observed for many p-wave resonances in a compound nucleus and measurements were performed on several nuclei in the mass region of A{approximately}100 and A{approximately}230. The statistical model of the compound nucleus provides a theoretical basis for extracting mean-squared matrix elements from the experimental asymmetry data, and for interpreting the mean-squared matrix elements. The constraints on the weak meson-exchange couplings calculated from the compound-nucleus asymmetry data agree qualitatively with the results from few-body and light-nuclei experiments. The tests of time-reversal invariance in various experiments using thermal, epithermal and MeV neutrons are being developed.
Date: December 31, 1994
Creator: Yen, Yi-Fen; Bowman, J. D.; Frankle, C. M. & Crawford, B. E.
System: The UNT Digital Library
Manufacture and testing of the superconducting wire and cable for the RHIC dipoles and quadrupoles (open access)

Manufacture and testing of the superconducting wire and cable for the RHIC dipoles and quadrupoles

Production of superconducting wire and cable for RHIC dipoles and quadrupoles is now complete. This report presents final statistics generated during the manufacture and testing of this cable.
Date: December 31, 1994
Creator: Greene, A. F.; Garber, M. G.; Ghosh, A. K.; McChesney, D.; Morgillo, A.; Shah, R. et al.
System: The UNT Digital Library
Accelerator-based systems for plutonium destruction and nuclear waste transmutation (open access)

Accelerator-based systems for plutonium destruction and nuclear waste transmutation

Accelerator-base systems are described that can eliminate long-lived nuclear materials. The impact of these systems on global issues relating to plutonium minimization and nuclear waste disposal can be significant. An overview of the components that comprise these systems is given, along with discussion of technology development status and needs. A technology development plan is presented with emphasis on first steps that would demonstrate technical performance.
Date: December 31, 1994
Creator: Arthur, E. D.
System: The UNT Digital Library
Technical evaluation of a dual-junction same-band-gap amorphous silicon photovoltaic system at NREL (open access)

Technical evaluation of a dual-junction same-band-gap amorphous silicon photovoltaic system at NREL

On December 7, 1992, a 1.8-kW{sub ac} utility-interconnect photovoltaic (PV) system using amorphous silicon modules was brought on-line at the National Renewable Energy Laboratory`s photovoltaic test site. This system was deployed to conduct an in-situ technical evaluation of the PV array (in a high voltage configuration) and system performance and reliability in a utility-interconnect application. The system is unique due to the installation of construction-grade insulation on the back of each PV module. This use of insulation is an attempt to levelize the annual array power output by elevating the operating temperature of the modules. This paper presents array and system performance data. Emphasis is placed on quantifying the effects of individual losses as well as seasonal changes on PV array and system performance.
Date: December 1, 1994
Creator: Strand, T.; Mrig, L.; Hansen, R. & Emery, K.
System: The UNT Digital Library
Gamma-ray measurements at the WNR white neutron source (open access)

Gamma-ray measurements at the WNR white neutron source

Photon production data have been acquired in the incident neutron energy range, 1 < E{sub n} < 400 MeV, for a number of target nuclei, gamma-ray energy ranges, and reactions, using the continuous-energy neutron beam of the WNR facility at Los Alamos. Gamma-ray production measurements using high resolution Ge detectors have been employed for gamma-rays in the energy range, 0.1 < E{sub {gamma}} < 10 MeV. These measurements allow identification of reactions from the known energies of the gamma-ray transitions between low-lying states in the final nucleus. Some of the targets studied include: N, O, Al, Na, {sup 56}Fe, and {sup 207,208}Pb. These data are useful both for testing nuclear reaction models at intermediate energies and for numerous applied purposes. BGO detectors do not have the good energy resolution of Ge detectors, but have much greater detection efficiency for gamma rays with energies greater than a few MeV. We have used an array of 5 BGO detectors to measure cross sections and angular distributions for photon production from C and N. A large, well-shielded BGO detector has been used to measure fast neutron capture in the giant resonance region with a maximum gamma-ray energy of 52 MeV. We present results …
Date: December 31, 1994
Creator: Nelson, R. O.; Wender, S. A. & Mayo, D. R.
System: The UNT Digital Library
Proceedings of the workshop on future hadron facilities in the US (open access)

Proceedings of the workshop on future hadron facilities in the US

This report discusses the following topics on future hadron facilities: Workshop on future hadron facilities in the US; 30 {times} 30 TeV-summary report; A high luminosity, 2 {times} 2 TeV collider in the tevatron tunnel; magnets working group; cryogenics discussion; vacuum report; antiproton source production; injector working group; interaction region working group; lattice/beam dynamics working group; LEBT for high-luminosity colliders; some notes on long-range beam-beam effects for the 2TeV collider; synchrotron radiation masks for high energy proton accelerators. Emittance preservation in a proton synchrotron; beam-beam interaction effects on betatron tunes; analytic solutions for phase trombone modules; and chromatic corrections of RHIC when one or two insertions is at {Beta}* = 0.5m.
Date: December 31, 1994
Creator: unknown
System: The UNT Digital Library
Optical properties of fractal nanocomposites (open access)

Optical properties of fractal nanocomposites

Optical prossesses in nanostructured fractal composites are shown to be strongly enhanced. The enhancement occurs because of a localization of dipolar eigenmodes in subwavelength areas.
Date: December 31, 1994
Creator: Markel, V. A.; Kim, W.; Armstrong, R.; Shalaev, V. & Stechel, E. B.
System: The UNT Digital Library
Accelerator modeling system for the future (open access)

Accelerator modeling system for the future

Many computer programs and a variety of models exist for the design of accelerator lattices and the correction of errors. Many physicists contributed to this work by developing codes to suit a variety of machines. At present, we are integrating some of these codes into a unified framework to design and control any type of machine. We will refer to this system of interactive accelerator design, control, and analysis codes as the All-In-One Modeling system (AIM). This paper will explore the utilities of AIM for future accelerator modeling and control. As an example, we will describe a procedure to produce both a linear and a nonlinear model for SPEAR.
Date: December 1, 1994
Creator: Lee, M.; Cai, Y. & Tran, P.
System: The UNT Digital Library
Effects of carbon blending and granule size layering on butane breakthrough curves (open access)

Effects of carbon blending and granule size layering on butane breakthrough curves

None
Date: December 1, 1994
Creator: Wood, G. O. & Karwacki, C.
System: The UNT Digital Library
Taylor series expansion and modified extended Prony analysis for localization (open access)

Taylor series expansion and modified extended Prony analysis for localization

In the multiple source localization problem, many inverse routines use a rooting of a polynomial to determine the source locations. The authors present a rooting algorithm for locating an unknown number of three-dimensional, near-field, static sources from measurements at an arbitrarily spaced three-dimensional array. Since the sources are near-field and static, the spatial covariance matrix is always rank one, and spatial smoothing approaches are inappropriate due to the spatial diversity. The authors approach the solution through spherical harmonics, essentially replacing the point source function with its Taylor series expansion. They then perform a modified extended Prony analysis of the expansion coefficients to determine the number and location of the sources. The full inverse method is typically ill-conditioned, but a portion of the algorithm is suitable for synthesis analysis. They present a simulation for simplifying point charges limited to a spherical region, using an array of voltage potential measurements made outside the region. Future efforts of this work will focus on adapting the analysis to the electroencephalography and magnetoencephalography.
Date: December 1, 1994
Creator: Mosher, J. C. & Lewis, P. S.
System: The UNT Digital Library
Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations (open access)

Buried Waste Integrated Demonstration lessons learned: 1993 technology demonstrations

An integrated technology demonstration was conducted by the Buried Waste Integrated Demonstration (BWID) at the Idaho National Engineering Laboratory Cold Test Pit in the summer of 1993. This program and demonstration was sponsored by the US Department of Energy Office of Technology Development. The demonstration included six technologies representing a synergistic system for the characterization and retrieval of a buried hazardous waste site. The integrated technology demonstration proved very successful and a summary of the technical accomplishments is presented. Upon completion of the integrated technology demonstration, cognizant program personnel participated in a lessons learned exercise. This exercise was conducted at the Simplot Decision Support Center at Idaho State University and lessons learned activity captured additional information relative to the integration of technologies for demonstration purposes. This information will be used by BWID to enhance program planning and strengthen future technology demonstrations.
Date: December 31, 1994
Creator: Kostelnik, K. M. & Owens, K. J.
System: The UNT Digital Library
Magnetic and structural properties of Fe/Pd multilayers studied by magnetic x-ray dichroism and x-ray absorption spectroscopy (open access)

Magnetic and structural properties of Fe/Pd multilayers studied by magnetic x-ray dichroism and x-ray absorption spectroscopy

The results of magnetic circular x-ray dichroism (MCXD) measurements and extended x-ray absorption fine structure measurements (EXAFS) of the Fe K-edges of textured Fe(110)/Pd(111) multilayers are reported. The EXAFS results indicates that the iron in the system goes from bcc to a more densely packed system as the thickness of the iron layer is decreased. The magnetic properties were measured by SQUID magnetometry from 5-350 K. For all the samples, the saturation magnetization was significantly enhanced over the bulk values indicating the interface Pd atoms are polarized by the Fe layer. The enhancement corresponds to a moment of {approx}2.5{mu}{sub B} per interface Pd atom.
Date: December 1, 1994
Creator: Mini, S. M.; Fullerton, E. E.; Sowers, C. H.; Fontaine, A.; Pizzini, S.; Bommannavar, A. S. et al.
System: The UNT Digital Library
Status of nuclear data for ITER applications (open access)

Status of nuclear data for ITER applications

As the development of a near-term fusion reactor, such as the International Thermonuclear Experimental Reactor (ITER), enters the engineering design activity phase, one of the essential elements leading to the successful design, construction and operation of such a reactor is nuclear data. High quality nuclear data for all reactor materials relevant to ITER will be required in order to assess the nuclear performance, radiation damage, and safety and environmental aspects of all reactor components. In this paper the authors review the current ITER design, noting which materials and associated nuclear data are important in the various reactor components. They also review the contents of the Fusion Evaluated Nuclear Data Library (FENDL) accepted for use by ITER, and identify materials for which nuclear data improvements are required.
Date: December 31, 1994
Creator: Larson, D. C.; Cheng, E. T.; Mann, F. M. & Saji, G.
System: The UNT Digital Library
Long-Baseline Neutrino Oscillation Experiments (open access)

Long-Baseline Neutrino Oscillation Experiments

There is no unambiguous definition for long baseline neutrino oscillation experiments. The term is generally used for accelerator neutrino oscillation experiments which are sensitive to {Delta}m{sup 2} < 1.0 eV{sup 2}, and for which the detector is not on the accelerator site. The Snowmass N2L working group met to discuss the issues facing such experiments. The Fermilab Program Advisory Committee adopted several recommendations concerning the Fermilab neutrino program at their Aspen meeting immediately prior to the Snowmass Workshop. This heightened the attention for the proposals to use Fermilab for a long-baseline neutrino experiment at the workshop. The plan for a neutrino oscillation program at Brookhaven was also thoroughly discussed. Opportunities at CERN were considered, particularly the use of detectors at the Gran Sasso laboratory. The idea to build a neutrino beam from KEK towards Superkamiokande was not discussed at the Snowmass meeting, but there has been considerable development of this idea since then. Brookhaven and KEK would use low energy neutrino beams, while FNAL and CERN would plan have medium energy beams. This report will summarize a few topics common to LBL proposals and attempt to give a snapshot of where things stand in this fast developing field.
Date: December 31, 1994
Creator: Crane, Dan & Goodman, Maury
System: The UNT Digital Library
The hard truth (open access)

The hard truth

In the Bayesian methodology, the posterior probability combines uncertainty about prior knowledge, and available data about alternative models of reality. The posterior quantifies the degree of certainty one has in inferring the truth in terms of those models. We propose a method to determine the reliability of a specific feature of a Bayesian solution. Our approach is based on an analogy between the negative logarithm of the posterior and a physical potential. This analogy leads to the interpretation of gradient of this potential as a force that acts on the model. As model parameters are perturbed from their maximum a posteriori (MAP) values, the strength of the restoring force that drives them back to the MAP solution is directly related to the reliability of those parameter estimates. The correlations between the uncertainties of parameter estimates can be elucidated.
Date: December 31, 1994
Creator: Hanson, K. M. & Cunningham, C. S.
System: The UNT Digital Library
High surface area, high permeability carbon monoliths (open access)

High surface area, high permeability carbon monoliths

The goal of this work is to prepare carbon monoliths having precisely tailored pore size distribution. Prior studies have demonstrated that poly(acrylonitrile) can be processed into a precursor having tailored macropore structure. Since the macropores were preserved during pyrolysis, this synthetic process provided a route to porous carbon having macropores with size =0.1 to 10{mu}m. No micropores of size <2 nm could be detected in the carbon, however, by nitrogen adsorption. In the present work, the authors have processed a different polymer, poly(vinylidene chloride) into a macroporous precursor, Pyrolysis produced carbon monoliths having macropores derived from the polymer precursor as well as extensive microporosity produced during the pyrolysis of the polymer. One of these carbons had BET surface area of 1,050 m{sup 2}/g and about 1.2 cc/g total pore volume, with about 1/3 of the total pore volume in micropores and the remainder in 1{mu}m macropores. No mesopores in the intermediate size range could be detected by nitrogen adsorption. Carbon materials having high surface area as well as micron size pores have potential applications as electrodes for double layer supercapacitors containing liquid electrolyte, or as efficient media for performing chemical separations.
Date: December 31, 1994
Creator: Lagasse, R. R. & Schroeder, J. L.
System: The UNT Digital Library
Tau as a probe for new physics (open access)

Tau as a probe for new physics

The usage of polarimetry and spin-correlation tests to determine the complete Lorenz structure of the tau lepton`s charged and neutral- current couplings is reviewed. The emphasis is on tests for ``something`` in a (V-A)+ ``something`` structure in J{sup charged} Lepton current, so as to bound the scales {lambda} for ``new physics`` such as arising from tau weak magnetism, weak electricity, and/or second-class currents. Tests for T and for CP violation are discussed.
Date: December 31, 1994
Creator: Nelson, C. A.
System: The UNT Digital Library