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0. 20-m (8-in.) Primary Burner Development Report

Description: High-Temperature Gas-Cooled Reactors (HTGRs) utilize graphite-base fuels. Fluidized-bed burners are being employed successfully in the experimental reprocessing of these fuels. The primary fluidized-bed burner is a unit operation in the reprocessing flowsheet in which the graphite moderator is removed. A detailed description of the development status of the 0.20-m (8-in.) diameter primary fluidized-bed burner as of July 1, 1977 is presented. Experimental work to date performed in 0.10; 0.20; and 0.40-m (4, 8, and 16 in.) diameter primary burners has demonstrated the feasibility of the primary burning process and, at the same time, has defined more clearly the areas in which additional experimental work is required. The design and recent operating history of the 0.20-m-diameter burner are discussed, with emphasis placed upon the evolution of the current design and operating philosophy.
Date: December 1977
Creator: Stula, R. T.; Young, D. T. & Rode, J. S.
Partner: UNT Libraries Government Documents Department
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0.351 micron Laser Beam propagation in High-temperature Plasmas, 2007, December 21

Description: A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (T{sub e} = 3.5 keV), dense (n{sub e} = 5 x 10{sup 20}cm{sup -3}), long-scale length (L {approx} 2 mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I < 2 x 10{sup 15} W-cm{sup -2}. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2 keV to 3.5 keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. A plasma length scaling is also investigated extending our measurements to 4-mm long high-temperature plasmas. At intensities I < 5 x 10{sup 14} W-cm{sup -2}, greater than 80% of the energy in the laser is transmitted through a 5-mm long, high-temperature (T{sub e} > 2.5 keV) high-density (n{sub e} = 5 x 10{sup 20} w-cm{sup -3}) plasma. Comparing the experimental results with detailed gain calculations for the onset of significant laser scattering processes shows a stimulated Brillouin scattering threshold (R=10%) for a linear gain of 15; these high temperature, low density experiments produce plasma conditions comparable to those along the outer beams in ignition hohlraum designs. By increasing the gas fill density (n{sub e} = 10{sup 21} cm{sup -3}) in these …
Date: December 10, 2007
Creator: Froula, D.; Divol, L.; Meezan, N.; Ross, J.; Berger, R. L.; Michel, P. et al.
Partner: UNT Libraries Government Documents Department
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1/2 Sintering of Mullite-Containing Materials: I. Effect of Composition

Description: Sintering behavior of mullite-containing powders was studied over a range of chemical compositions (Al{sub 2}O{sub 3}/SiO{sub 2} ratio). Densification measurements were made for both liquid phase-containing and solid state systems. Small amounts of liquid phase were observed to have a significant effect on densification rate. A linear relationship was obtained between the percent of theoretical density and the logarithm of time for compositions in the range 73-75 wt% Al{sub 2}O{sub 3}. Currently available models for intermediate stage sintering kinetics were considered to be inadequate for these systems. Grain boundary transport 0r diffusion appeared to be the primary mechanism of densification.
Date: December 1, 1981
Creator: Sacks, Michael D. & Pask, Joseph A.
Partner: UNT Libraries Government Documents Department

[The 1,000th Ph.D. Recipient, #2]

Description: Photograph of the 1,000th student to graduate from North Texas State University with a Ph.D. degree. He is wearing dark-colored robes and a mortarboard, standing in the corner of a wood-paneled room. An unidentified faculty member is standing in front of him and shaking his hand.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #3]

Description: Photograph of a student wearing commencement robes and a mortarboard, shaking hands with an unidentified faculty member (left). The student is the 1,000 person to graduate from North Texas State University with a Ph.D. degree. They are standing in the corner of a wood-paneled room and several framed certificates and plaques are on the wall in the right side of the image.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #4]

Description: Photograph an unidentified faculty member shaking hands with the 1,000th person to graduate from North Texas State University with a Ph.D. degree. The student is wearing dark-colored robes with a mortarboard. They are standing in the corner of a wood-paneled room with floor-to-ceiling curtains to the left.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #5]

Description: Photograph of an unidentified faculty member with the 1,000th recipient of a North Texas State University Ph.D. degree; they are shaking hands, but turned so that both of them can look at the camera. The student is wearing dark-colored graduation robes and a mortarboard. They are standing in the corner of a wood-paneled room.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #6]

Description: Photograph of the 1,000th graduate to receive a Ph.D. from North Texas State University, shaking hands with an unidentified professor, turned so that they can both face the camera. The student is wearing dark-colored graduation robes and a mortarboard; the tassel is partially obscuring his face. They are standing in the corner of a wood-paneled room.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #7]

Description: Photograph of a student wearing graduation robes and a mortarboard, standing between two unidentified faculty members, who are facing him. The student is the 1,000 person to graduate from North Texas State University with a Ph.D. degree. They are standing in the corner of a wood-paneled room, in front of a statue on a pedestal that is partially visible in the center of the image.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #8]

Description: Photograph of the 1,000th student to graduate from North Texas State University with a Ph.D. degree. He is wearing dark-colored robes and a mortarboard, standing in the corner of a wood-paneled room. An unidentified faculty member is standing in front of him and is excitedly waving his hands up.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #9]

Description: Photograph of a student wearing graduation robes and a mortarboard, standing between two unidentified faculty members, shaking hands with the man to his left. The student is the 1,000 person to graduate from North Texas State University with a Ph.D. degree. They are standing in the corner of a wood-paneled room.
Date: December 22, 1975
Partner: UNT Libraries Special Collections

[The 1,000th Ph.D. Recipient, #10]

Description: Photograph of a student wearing graduation robes and a mortarboard, standing between two unidentified faculty members, shaking hands with the man to his left. The student is the 1,000 person to graduate from North Texas State University with a Ph.D. degree. They are standing in the corner of a wood-paneled room.
Date: December 22, 1975
Partner: UNT Libraries Special Collections
open access

1-D Van der Waals Foams Heated by Ion Beam Energy Deposition

Description: One dimensional simulations of various initial average density aluminum foams (modeled as slabs of solid metal separated by low density regions) heated by volumetric energy deposition are conducted with a Lagrangian hydrodynamics code using a van der Waals equation of tate (EOS). The resulting behavior is studied to facilitate the design of future warm dense matter (WDM) experiments at LBNL. In the simulations the energy deposition ranges from 10 to 30 kJ/g and from 0.075 to 4.0 ns total pulse length, resulting in temperatures from approximately 1 o 4 eV. We study peak pressures and temperatures in the foams, expansion velocity, and the phase evolution. Five relevant time scales in the problem are identified. Additionally, we present a method for characterizing the level of inhomogeneity in a foam target as it is heated and the time it takes for a foam to homogenize.
Date: December 23, 2009
Creator: Zylstra, A. B.; Barnard, J. J. & More, R. M.
Partner: UNT Libraries Government Documents Department
open access

1 MeV electron irradiation of solid Xe nanoclusters in Al : an in-situ HRTEM study.

Description: Thin film samples of a simple embedded nanocluster system consisting of solid Xe precipitates in Al have been subjected to 1 MeV electron irradiation in a high-voltage electron microscope. High-resolution images have been recorded on videotape in order to monitor the changes to the system resulting from the passage of electrons through the film. Inspection of the video recordings (in some cases frame-by-frame) reveals that complex, rapid processes occur under the electron beam. These include, movement of small clusters, coalescence of neighboring clusters, shape changes, the apparent melting and resolidification of the Xe, and the creation and annealing of extended defects within the Xe lattice. A tentative interpretation of some of the observations is presented in terms of the electron-induced displacement processes at the surface of the clusters.
Date: December 5, 1997
Creator: Donnelly, S. E.; Furuya, K.; Song, M.; Birtcher, R. C. & Allen, C. W.
Partner: UNT Libraries Government Documents Department
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(02.2) Scoping experiments; (02.3) long-term corrosion testing and properties evaluation of candidate waste package basket material

Description: The work described in this activity plan addresses Information Need 2.7.3 of the Yucca Mountain Site Characterization Plan (l), which reads Determination that the design criteria in lOCFR60.130 through 60.133 and any appropriate additional design objectives pertaining to criticality control have been met. This work falls under section WBS 1.2.2.5 2 (Basket Materials) of WBS 1.2.2.5 (Waste Package Materials) in the Work Breakdown Structure of the Yucca Mountain Site Characterization Project.
Date: December 20, 1996
Creator: VanKonynenburg, R. A.
Partner: UNT Libraries Government Documents Department
open access

2-D Finite Element Cable and Box IEMP Analysis

Description: A 2-D finite element code has been developed for the solution of arbitrary geometry cable SGEMP and box IEMP problems. The quasi- static electric field equations with radiation- induced charge deposition and radiation-induced conductivity y are numerically solved on a triangular mesh. Multiple regions of different dielectric materials and multiple conductors are permitted.
Date: December 17, 1998
Creator: Scivner, G.J. & Turner, C.D.
Partner: UNT Libraries Government Documents Department
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2-D Modeling of Energy-z Beam Dynamics Using the LiTrack Matlab Program

Description: Short bunches and the bunch length distribution have important consequences for both the LCLS project at SLAC and the proposed ILC project. For both these projects, it is important to simulate what bunch length distributions are expected and then to perform actual measurements. The goal of the research is to determine the sensitivity of the bunch length distribution to accelerator phase and voltage. This then indicates the level of control and stability that is needed. In this project I simulated beamlines to find the rms bunch length in three different beam lines at SLAC, which are the test beam to End Station A (ILC-ESA) for the ILC studies, Linac Coherent Light Source (LCLS) and LCLS-ESA. To simulate the beamlines, I used the LiTrack program, which does a 2-dimensional tracking of an electron bunch's longitudinal (z) and the energy spread beam (E) parameters. In order to reduce the time of processing the information, I developed a small program to loop over adjustable machine parameters. LiTrack is a Matlab script and Matlab is also used for plotting and saving and loading files. The results show that the LCLS in Linac-A is the most sensitive when looking at the ratio of change in phase degree to rate of change. The results also show a noticeable difference between the LCLS and LCLS-ESA, which suggest that further testing should go into looking the Beam Switch Yard and End Station A to determine why the result of the LCLS and LCLS-ESA vary.
Date: December 15, 2005
Creator: Cauley, S .K. & Woods, M.
Partner: UNT Libraries Government Documents Department
open access

2-D time evolution of T/sub e/ during sawtooth crash based on fast ECE (electron cyclotron emission) measurements on TFTR

Description: Electron cyclotron emission measurements taken at 20 locations in the horizontal midplane during a sawtooth crash have been analysed based on the assumption of fast rigid rotation of the plasma. Due to this fast rotation (approx.100..mu..sec), which remains fairly constant throughout the sawtooth crash, we have been able to make time-to-space reconstructions of half the poloidal plane using points which are separated in time by not more than 40..mu..sec. The existence of a temperature flattening in the precursor phase, which we interpret as an m = 1 temperature island, is clearly demonstrated, and its location and width agree well with local emissivity measurements from soft x-ray tomography viewing the same poloidal plane. The rotating temperature island in the precursor phase, the outward movement of the region of high T/sub c/ during the crash phase, and the shape of T/sub e/ during the crash phase, and the shape of T/sub e/ distribution after the crash during the successor phase have all been documented in a time sequence of color contours. 4 refs., 10 figs.
Date: December 1, 1988
Creator: Kuo-Petravic, G.
Partner: UNT Libraries Government Documents Department
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2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures

Description: The work done consists of three parts: optimizing the disk-and-washer (DAW) structure at ..beta.. = 0.5662 corresponding to E = 200 MeV; comparing the DAW structure with the side-coupled (SCS) structure at various values of beta, ranging from ..beta.. = 0.4569 and E = 116 MeV to ..beta.. = 0.7131 and E = 400 MeV; and re-optimizing the DAW structure at ..beta.. = 0.7131. 4 refs., 51 figs., 41 tabs.
Date: December 1, 1987
Creator: Larry, L.D. Jr.
Partner: UNT Libraries Government Documents Department
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2 MV Injector as the Elise Front-End and as an Experimental Facility

Description: We report on progress in the preparation of the 2 MV Injector at LBNL as the front-end of Elise, and as a multi-purpose experimental facility for Heavy Ion Fusion beam dynamics studies. Recent advances on the performance and understanding of the injector are described, and some of the on-going experimental activities are summarized.
Date: December 7, 1999
Creator: Yu, S. S.; Eylon, S.; Henestroza, E.; Peters, C.; Reginato, L.; Tauschwitz, A. et al.
Partner: UNT Libraries Government Documents Department
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3-D field computations for accelerator magnets using finite element and integral codes

Description: Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960`s, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: December 1, 1992
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Partner: UNT Libraries Government Documents Department
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A 3-D numerical study of pinhole diffraction to predict the accuracy of EUV point diffraction interferometry

Description: A 3-D electromagnetic field simulation is used to model the propagation of extreme ultraviolet (EUV), 13-nm, light through sub-1500 {Angstrom} dia pinholes in a highly absorptive medium. Deviations of the diffracted wavefront phase from an ideal sphere are studied within 0.1 numerical aperture, to predict the accuracy of EUV point diffraction interferometersused in at-wavelength testing of nearly diffraction-limited EUV optical systems. Aberration magnitudes are studied for various 3-D pinhole models, including cylindrical and conical pinhole bores.
Date: December 1, 1995
Creator: Goldberg, K.A.; Tejnil, E. & Bokor, J.
Partner: UNT Libraries Government Documents Department
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3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface

Description: Under ER63662, 3-D Seismic Experimentation and Advanced Processing/Inversion Development for Investigations of the Shallow Subsurface, we have completed a number of subprojects associated with the Hill Air Force Base (HAFB) high resolution 3-D reflection/tomography dataset.
Date: December 1, 2004
Creator: Levander, Alan R.
Partner: UNT Libraries Government Documents Department
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