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1998 wire development workshop proceedings (open access)

1998 wire development workshop proceedings

This report consists of vugraphs of the presentations at the conference. The conference was divided into the following sessions: (1) First Generation Wire Development: Status and Issues; (2) First Generation Wire in Pre-Commercial Prototypes; (3) Second Generation Wire Development: Private Sector Progress and Issues; (4) Second Generation Wire Development: Federal Laboratories; and (5) Fundamental Research Issues for HTS Wire Development.
Date: April 1, 1998
Creator: unknown
Object Type: Article
System: The UNT Digital Library
1999 vadose zone monitoring plan and guidance for subsequent years (open access)

1999 vadose zone monitoring plan and guidance for subsequent years

The US Department of Energy`s Hanford Site has the most diverse and largest amounts of radioactive waste in the US. The majority of the liquid waste was disposed to the soil column where much of it remains today. This document provides the rationale and general framework for vadose zone monitoring at cribs, ditches, trenches and other disposal facilities to detect new sources of contamination and track the movement of existing contamination in the vadose zone for the protection of groundwater. The document provides guidance for subsequent site-specific vadose zone monitoring plans and includes a brief description of past vadose monitoring activities (Chapter 3); the results of the Data Quality Objective process used for this plan (Chapter 4); a prioritization of liquid waste disposal sites for vadose monitoring (Chapter 5 and Appendix B); a general Monitoring and Analysis Plan (Chapter 6); a general Quality Assurance Project Plan (Appendix A), and a description of vadose monitoring activities planned for FY 1999 (Appendix C).
Date: August 1, 1998
Creator: Horton, D. G.; Reidel, S. P. & Last, G. V.
Object Type: Report
System: The UNT Digital Library
2020 Vision Project Summary, FY98 (open access)

2020 Vision Project Summary, FY98

The 2020 Vision project began in 1996 with two participating teachers and four classes. It has since grown to comprise more than a dozen participating teachers and hundreds of students across the country. Much of this growth took place in FY98, thanks to the accomplishment of several major goals: implementation of a mentor program, enhanced teacher training, a mid-year conference for students, recruitment of distant schools, and the development of an interactive Web site. The first part of this report describes these accomplishments, as well as future directions for 2020 Vision. The second part summarized the scenarios students wrote during the 1997-98 school year. it identifies recurrent themes in the students' scenarios and compares/contrasts them with scenarios written in the first two years of the project.
Date: November 1, 1998
Creator: Munoz, A.; Clausen, J. C.; Scott, K. P. & Gordon, K. W.
Object Type: Report
System: The UNT Digital Library
2K nonvolatile shadow RAM and 265K EEPROM SONOS nonvolatile memory development (open access)

2K nonvolatile shadow RAM and 265K EEPROM SONOS nonvolatile memory development

This paper describes Silicon Oxide Nitride Oxide Semiconductor (SONOS) nonvolatile memory development at Sandia National Laboratories. A 256K EEPROM nonvolatile memory and a 2K nonvolatile shadow RAM are under development using an n-channel SONOS memory technology. The technology has 1.2 {micro}m minimum features in a twin well design using shallow trench isolation.
Date: July 1, 1998
Creator: Nasby, R. D.; Murray, J. R.; Habermehl, S. D.; Bennett, R. S.; Tafoya-Porras, B. C.; Mahl, P. R. et al.
Object Type: Article
System: The UNT Digital Library
3d-Metal Doped into LiMn2O4 Thin Films (open access)

3d-Metal Doped into LiMn2O4 Thin Films

3d-metal (Me) doped LiMn{sub 2}O{sub 4} thin films were deposited by rf magnetron sputtering of Li[Mn{sub 1.9}Me{sub 0.1}]O{sub 4} targets in Ar + N{sub 2} and Ar + O{sub 2} gas mixtures and annealed at 750{degrees}C in O{sub 2} for 1 h. From XRD measurements, the structure of the Me-doped thin film was dependent upon the element and the deposition conditions. The doping level of Me/Mn of cubic phase was less than 0.1 by EDX measurements. The Ti-LiMn{sub 2}O{sub 4} films exhibited a capacity close to theoretical for stoichiometric LiMn{sub 2}O{sub 4}. This improvement at 4 V comes at the expense of the capacity at 5 V. Cells with Ti-doped films exhibited the same low capacity fade as those with undoped LiMn{sub 2}O{sub 4} cathodes. Similar electrochemical changes were observed with the Cr- and Zn-LiMn{sub 2}O{sub 4} films. The discharge capacities above 4.5 V for the Ni-doped films were about equal to those below 4.5 V, and the thin-film cells could be cycled reversibility between 3.5 and 5.3 V.
Date: November 1, 1998
Creator: Bates, J.B.; Ueda, A. & Zuhr, R.A.
Object Type: Article
System: The UNT Digital Library
3D Simulations of line emission from ICF capsules (open access)

3D Simulations of line emission from ICF capsules

Line emission from ICF implosions can be used to diagnose the temperature of the DT fuel and provides an indication of the distortion in the fuel-pusher interface. 2D simulations have provided valuable insights into the usefulness of argon and titanium dopants as diagnostics of instabilities. Characterizing the effects of drive asymmetries requires 3D modeling with large demands for computer time and memory, necessitating the use of parallel computers. We present the results of some 3D simulations achieved with a code utilizing both shared memory and distributed parallelism. We discuss the code structure and related performance issues.
Date: October 1, 1998
Creator: Langer, S.; Marinak, M. M. & Scott, H.
Object Type: Article
System: The UNT Digital Library
3He Neutral Current Detectors at SNO (open access)

3He Neutral Current Detectors at SNO

The flux of solar neutrinos measured via charged and neutral current interactions can provide a model independent test of neutrino oscillations. Since the Sudbury Neutrino Observatory uses heavy water as a target, it has a large sensitivity to both interactions. A technique for observing the neutral current breakup of the deuteron using {sup 3}He proportional counters is described.
Date: September 1, 1998
Creator: Elliott, S. R.; Browne, M. C. & Doe, P. J.
Object Type: Article
System: The UNT Digital Library
7th International Meshing Roundtable '98 (open access)

7th International Meshing Roundtable '98

The goal of the 7th International Meshing Roundtable is to bring together researchers and developers from industry, academia, and government labs in a stimulating, open environment for the exchange of technical information related to the meshing process. In the past, the Roundtable has enjoyed significant participation from each of these groups from a wide variety of countries.
Date: October 1, 1998
Creator: Eldred, T.J.
Object Type: Article
System: The UNT Digital Library
Ab Initio Calculation of Nuclear Magnetic Resonance Chemical Shift Anisotropy Tensors 1. Influence of Basis Set on the Calculation of 31P Chemical Shifts (open access)

Ab Initio Calculation of Nuclear Magnetic Resonance Chemical Shift Anisotropy Tensors 1. Influence of Basis Set on the Calculation of 31P Chemical Shifts

The influence of changes in the contracted Gaussian basis set used for ab initio calculations of nuclear magnetic resonance (NMR) phosphorous chemical shift anisotropy (CSA) tensors was investigated. The isotropic chemical shitl and chemical shift anisotropy were found to converge with increasing complexity of the basis set at the Hartree-Fock @IF) level. The addition of d polarization function on the phosphorous nucIei was found to have a major impact of the calculated chemical shi~ but diminished with increasing number of polarization fimctions. At least 2 d polarization fimctions are required for accurate calculations of the isotropic phosphorous chemical shift. The introduction of density fictional theory (DFT) techniques through tie use of hybrid B3LYP methods for the calculation of the phosphorous chemical shift tensor resulted in a poorer estimation of the NMR values, even though DFT techniques result in improved energy and force constant calculations. The convergence of the W parametem with increasing basis set complexity was also observed for the DFT calculations, but produced results with consistent large deviations from experiment. The use of a HF 6-31 l++G(242p) basis set represents a good compromise between accuracy of the simulation and the complexity of the calculation for future ab initio calculations …
Date: September 1, 1998
Creator: Alam, T.M.
Object Type: Report
System: The UNT Digital Library
ABAREX -- A neutron spherical optical-statistical-model code -- A user`s manual (open access)

ABAREX -- A neutron spherical optical-statistical-model code -- A user`s manual

The contemporary version of the neutron spherical optical-statistical-model code ABAREX is summarized with the objective of providing detailed operational guidance for the user. The physical concepts involved are very briefly outlined. The code is described in some detail and a number of explicit examples are given. With this document one should very quickly become fluent with the use of ABAREX. While the code has operated on a number of computing systems, this version is specifically tailored for the VAX/VMS work station and/or the IBM-compatible personal computer.
Date: June 1, 1998
Creator: Smith, A. B. & Lawson, R. D.
Object Type: Report
System: The UNT Digital Library
About the realization of laser acceleration schemes based on plasmoids in r.f. wells (open access)

About the realization of laser acceleration schemes based on plasmoids in r.f. wells

The laser acceleration of plasmoids is investigated theoretically. Preliminary studies suggest that this configuration, which is based on the forced oscillations of finite pieces of plasma contained in moving or vibrating r.f. wells, has very much simplified plasma physics compared to that of other plasma-based ion acceleration schemes. It is necessary to consider the case when the applied electric field, E, of frequency {omega}, is large, E {le} e/4{pi}{var_epsilon}{sub o}r{lambda}, where r is the Classical electron radius and when the plasma density, n, is high n < 1/r{lambda}{sup 2}. Realization of this proposal requires the development, among other things, of biresonant accelerating systems including oversized single-mode tue-like resonators and the connection of this resonator to a terawatt FELs. If these problems, which will be delineated, are overcome--and progress in optics gives one reason to believe they can be--then gradients of {approximately} 10 GeV/m can be attained. Preliminary design of a linac, based upon this proposal and of a proof-of-principle experiment are presented.
Date: June 1, 1998
Creator: Sessler, A. M.; Wurtele, J. S.; Dzergach, A. I. & Kabanov, V. S.
Object Type: Article
System: The UNT Digital Library
Absolute, soft x-ray calorimetry on the Z facility at Sandia National Laboratories (open access)

Absolute, soft x-ray calorimetry on the Z facility at Sandia National Laboratories

Simple and reliable x-ray fluence measurements, in addition to time-resolved diagnostics, are needed to understand the physics of hot Z-pinch plasmas. A commercially available laser calorimeter has been modified for measuring soft x-ray fluence from the Z facility at Sandia National Laboratories. The x-ray absorber of this calorimeter is an aluminum disk, attached to a two-dimensional thermopile and surrounded by an isoperibol shroud. The time-integral and the maximum of the thermopile voltage signal are both proportional to the x-ray energy deposited. Data are collected for 90 seconds, and the instrument has, thus far, been used in the 1--25 mJ range. A wider dynamic measuring range for x-ray fluence (energy/area) can be achieved by varying the area of the defining aperture. The calorimeter is calibrated by an electrical substitution method. Calibrations are performed before and after each x-ray experiment on the Z facility. The calibration of the time-integral of the thermopile voltage vs. energy deposited (or the peak of thermopile voltage vs. energy deposited) is linear with zero offset at the 95% confidence level. The irreproducibility of the calibration is <2%, and the imprecision in the measurement of the incident x-ray energy (inferred from signal noise and the calibration) is estimated …
Date: May 1, 1998
Creator: Fehl, D. L.; Muron, D. J.; Leeper, R. J.; Chandler, G. A.; Deeney, C. & Spielman, R. B.
Object Type: Article
System: The UNT Digital Library
Absorbers for the high luminosity insertions of the LHC (open access)

Absorbers for the high luminosity insertions of the LHC

At design luminosity and inelastic cross section {sigma}{sub pp} = 80mb there are 8 {times} 10{sup 8} inelastic collisions per second at the high luminosity interaction points IP1 and IP5 of the LHC. These interactions give rise to {approximately} 0.9 kW of power in collision products leaving an IP in each direction. The inelastic collision power carried off by neutrals, mostly neutrons and photons, in each direction and intercepted by neutral absorbers (TAN) has been estimated with the MARS13 code to be 210W. Similarly the collision power escaping the beam tube and incident on the front face of the inner triplet quadrupole absorber (TAS) has been estimated to be {approximately} 270W, mostly carried by charged pions and photons. Special purpose absorbers must intercept this power to prevent quenching the inner triplet quadrupoles (Q1 to Q3) and the twin aperture magnets outside the second beam separation dipole D2. Because of the high incident flux of collision products near zero degrees the absorbers are natural places to consider for the location of radiation hard gas ionization detectors which could be used for: (1) measurement of luminosity, (2) measurement of the beam transverse dimensions at the IP and (3) feedback control of the …
Date: June 1, 1998
Creator: Turner, W. C.; Hoyer, E. H. & Mokhov, N. V.
Object Type: Article
System: The UNT Digital Library
Abstracts of computer programs and data libraries pertaining to photon production data (open access)

Abstracts of computer programs and data libraries pertaining to photon production data

Abstracts, or descriptions, of computer programs and data libraries pertaining to Photon Production Data (Measurements, Evaluations and Calculations) maintained in the collections of the Radiation Safety Information Computational Center, Oak Ridge, Tennessee USA and at the OECD/NEA Data Bank, Paris, are collected in this document.
Date: June 1, 1998
Creator: White, J.E.; Manneschmidt, J.B.; Finch, S.Y. & Dickens, J.K.
Object Type: Report
System: The UNT Digital Library
An AC phase measuring interferometer for measuring dn/dT of fused silica and calcium fluoride at 193 nm (open access)

An AC phase measuring interferometer for measuring dn/dT of fused silica and calcium fluoride at 193 nm

A novel method for the measurement of the change in index of refraction vs. temperature (dn/dT) of fused silica and calcium fluoride at the 193 nm wavelength has been developed in support of thermal modeling efforts for the development of 193 nm-based photolithographic exposure tools. The method, based upon grating lateral shear interferometry, uses a transmissive linear grating to divide a 193 nm laser beam into several beam paths by diffraction which propagate through separate identical material samples. One diffracted order passing through one sample overlaps the undiffracted beam from a second sample and forms interference fringes dependent upon the optical path difference between the two samples. Optical phase delay due to an index change from heating one of the samples causes the interference fringes to change sinusoidally with phase. The interferometer also makes use of AC phase measurement techniques through lateral translation of the grating. Results for several samples of fused silica and calcium fluoride are demonstrated.
Date: September 1, 1998
Creator: Shagam, R.N.
Object Type: Report
System: The UNT Digital Library
Accelerated Cleanup Risk Reduction (open access)

Accelerated Cleanup Risk Reduction

There is no proven technology for remediating contaminant plume source regions in a heterogeneous subsurface. This project is an interdisciplinary effort to develop the requisite new technologies so that will be rapidly accepted by the remediation community. Our technology focus is hydrous pyrolysis/oxidation (HPO) which is a novel in situ thermal technique. We have expanded this core technology to leverage the action of steam injection and place an in situ microbial filter downstream to intercept and destroy the accelerated movement of contaminated groundwater. Most contaminant plume source regions, including the chlorinated solvent plume at LLNL, are in subsurface media characterized by a wide range in hydraulic conductivity. At LLNL, the main conduits for contaminant transport are buried stream channels composed of gravels and sands; these have a hydraulic conductivity in the range of 10{sup -1} to 10{sup -2} cm/s. Clay and silt units with a hydraulic conductivity of 10{sup -1} to 10{sup -6} cm/s bound these buried channels; these are barriers to groundwater movement and contain the highest contaminant concentrations in the source region. New remediation technologies are required because the current ones preferentially access the high conductivity units. HPO is an innovative process for the in situ destruction of …
Date: February 1, 1998
Creator: Knapp, R. B.; Aines, R. M.; Blake, R. G.; Copeland, A. B.; Newmark, R. L. & Tompson, A. F. B.
Object Type: Report
System: The UNT Digital Library
Accelerating cleanup: Paths to closure (open access)

Accelerating cleanup: Paths to closure

This report describes the status of Environmental Management`s (EM`s) cleanup program and a direction forward to complete achievement of the 2006 vision. Achieving the 2006 vision results in significant benefits related to accomplishing EM program objectives. As DOE sites accelerate cleanup activities, risks to public health, the environment, and worker safety and health are all reduced. Finding more efficient ways to conduct work can result in making compliance with applicable environmental requirements easier to achieve. Finally, as cleanup activities at sites are completed, the EM program can focus attention and resources on the small number of sites with more complex cleanup challenges. Chapter 1 describes the process by which this report has been developed and what it hopes to accomplish, its relationship to the EM decision-making process, and a general background of the EM mission and program. Chapter 2 describes how the site-by-site projections were constructed, and summarizes, for each of DOE`s 11 Operations/Field Offices, the projected costs and schedules for completing the cleanup mission. Chapter 3 presents summaries of the detailed cleanup projections from three of the 11 Operations/Field Offices: Rocky Flats (Colorado), Richland (Washington), and Savannah River (South Carolina). The remaining eight Operations/Field Office summaries are in Appendix …
Date: June 1, 1998
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Accelerator Physics R and D. Final Technical Report for the Period December 15, 1993--December 14, 1997 (open access)

Accelerator Physics R and D. Final Technical Report for the Period December 15, 1993--December 14, 1997

During the 1990's, we focused our Accelerator Physics program on research and development of TeV polarized proton beams using Siberian snakes (a Siberian snake is a device which forces an accelerator ring's depolarizing fields to cancel themselves by rotating each proton's spin by 180{degree} on each turn around the ring): (1) Siberian snake experiments at the IUCF Cooler ring; (2) Design of polarized beam capability for the SSC; (3) Design of polarized beam capability for the Main Injector and Tevatron (funded by Fermilab); and (4) Design of polarized beam capability for HERA (funded by DESY). During FY 1994 to 1997, our Siberian snake experiments at IUCF continued to be unexpectedly successful. Their data have helped us to design polarized proton beam capability for Fermilab's Tevatron and Main Injector and now for DESY'S HERA.
Date: May 1, 1998
Creator: Krisch, A.D.
Object Type: Report
System: The UNT Digital Library
Accelerator Production of Tritium - Design Execution Plan (open access)

Accelerator Production of Tritium - Design Execution Plan

None
Date: September 1, 1998
Creator: Gattoni, W.C.
Object Type: Report
System: The UNT Digital Library
Accelerator Production of Tritium PPO Management Plan (open access)

Accelerator Production of Tritium PPO Management Plan

None
Date: March 1, 1998
Creator: Fultonberg, D.N.
Object Type: Report
System: The UNT Digital Library
Accelerator Production of Tritium Software Management Plan (open access)

Accelerator Production of Tritium Software Management Plan

None
Date: June 1, 1998
Creator: Olsen, B.
Object Type: Report
System: The UNT Digital Library
Accelerator Production of Tritium Waste Characterization and Certification Challenges (open access)

Accelerator Production of Tritium Waste Characterization and Certification Challenges

This paper summaries the processes and methods APT used for the identification and classification of the waste streams, the characterization and certification of the waste streams, and waste minimization.
Date: June 1, 1998
Creator: Ades, M. J.; England, J. L.; Nowacki, P. L.; Hane, R.; Tempel, K. L.; Pitcher, E. et al.
Object Type: Article
System: The UNT Digital Library
Accelerator scenario and parameters for the first muon collider and front-end of a muon collider (open access)

Accelerator scenario and parameters for the first muon collider and front-end of a muon collider

None
Date: March 1, 1998
Creator: Ankenbrandt, C. & Geer, S.
Object Type: Article
System: The UNT Digital Library
Accident sequences simulated at the Juragua nuclear power plant (open access)

Accident sequences simulated at the Juragua nuclear power plant

Different hypothetical accident sequences have been simulated at Unit 1 of the Juragua nuclear power plant in Cuba, a plant with two VVER-440 V213 units under construction. The computer code MELCOR was employed for these simulations. The sequences simulated are: (1) a design-basis accident (DBA) large loss of coolant accident (LOCA) with the emergency core coolant system (ECCS) on, (2) a station blackout (SBO), (3) a small LOCA (SLOCA) concurrent with SBO, (4) a large LOCA (LLOCA) concurrent with SBO, and (5) a LLOCA concurrent with SBO and with the containment breached at time zero. Timings of important events and source term releases have been calculated for the different sequences analyzed. Under certain weather conditions, the fission products released from the severe accident sequences may travel to southern Florida.
Date: August 1, 1998
Creator: Carbajo, J. J.
Object Type: Report
System: The UNT Digital Library