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0.5 μm E/D AlGaAs/GaAs heterostructure field effect transistor technology with DFET threshold adjust implant

Description: A doped-channel heterostructure field effect transistor (H-FET) technology has been developed with self-aligned refractory gate processing and using both enhancement- and depletion-mode transistors. D-HFET devices are obtained with a threshold voltage adjust implant into material designed for E-HFET operation. Both E- and D-HFETs utilize W/WSi bilayer gates, sidewall spacers, and rapid thermal annealing for controlling short channel effects. The 0.5 {mu}m E- HFETs (D-HFETs) have been demonstrated with transconductance of 425 mS/mm (265-310 mS/mm) and f{sub t} of 45-50 GHz. Ring oscillator gate delays of 19 ps with a power of 0.6 mW have been demonstrated using direct coupled FET logic. These results are comparable to previous doped-channel HFET devices and circuits fabricated by selective reactive ion etching rather than ion implantation for threshold voltage adjustment.
Date: April 1997
Creator: Baca, A. G.; Sherwin, M. E.; Zolper, J. C.; Shul, R. J.; Briggs, R. D.; Heise, J. A. et al.
Partner: UNT Libraries Government Documents Department

A 0. 5 to 3. 0 MeV monoenergetic positron beam

Description: An adjustable, 0.5--3 MeV monoenergetic positron beam has been constructed at Brookhaven. Currently a /sup 22/Na source with a W(100) foil transmission moderator produces a 1.1 mm FWHN beam with an intensity of 3/times/10/sup 5/ e/sup +//sec at a target located downstream from the accelerator. The divergence of the beam is less than 0.1/degree/ at 2.2 MeV energy. A SOA gun with 2 lens transport system brings the beam to a focus at the entrance of an electrostatic 3 MeV Dynamitron accelerator. The post acceleration beam transport system comprises 3 focusing solenolds, 4 sets of steering magnets and a 90/degree/ double focusing bending magnet. The beam energy spread at the target is <1 keV FWHN deduced from the beam size. Below we describe the positron extraction optics and acceleration, the construction of the beamline and the beam diagnostic devices. The salient beam parameters are listed at the end of this paper. 2 refs., 3 figs., 1 tab.
Date: 1988~
Creator: Huomo, H.; AsokaKumar, P.; Henderson, S. D.; Phlips, B. F.; Mayer, R.; McDonough, J. et al.
Partner: UNT Libraries Government Documents Department

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

0.25mm-Thick CCD Packaging for the Dark Energy Survey Camera Array

Description: Abstract: The Dark Energy Survey Camera focal plane array will consist of 62 2k x 4k CCDs with a pixel size of 15 microns and a silicon thickness of 250 microns for use at wavelengths between 400 and 1000 nm. Bare CCD die will be received from the Lawrence Berkeley National Laboratory (LBNL). At the Fermi National Accelerator Laboratory, the bare die will be packaged into a custom back-side-illuminated module design. Cold probe data from LBNL will be used to select the CCDs to be packaged. The module design utilizes an aluminum nitride readout board and spacer and an Invar foot. A module flatness of 3 microns over small (1 sqcm) areas and less than 10 microns over neighboring areas on a CCD are required for uniform images over the focal plane. A confocal chromatic inspection system is being developed to precisely measure flatness over a grid up to 300 x 300 mm. This system will be utilized to inspect not only room-temperature modules, but also cold individual modules and partial arrays through flat dewar windows.
Date: 2006-06~
Creator: Derylo, Greg; Diehl, H. Thomas & Estrada, Juan
Partner: UNT Libraries Government Documents Department

0-G experiments with advanced ceramic fabric wick structures

Description: Both Air Force and NASA future spacecraft thermal management needs span the temperature range from cryogenic to liquid metals. Many of these needs are changing and not well defined and will remain so until goals, technology, and missions converge. Nevertheless, it is certain that high-temperature (> 800 K) and medium-temperature (about 450 K) radiator systems will have to be developed that offer significant improvements over current designs. This paper discusses experiments performed in the lower temperature regime as part of a comprehensive advanced ceramic fabric (ACF) heat pipe development program. These experiments encompassed wicking tests with various ceramic fabric samples, and heat transfer tests with a 1-m long prototype ACF water heat pipe. A prototype ceramic fabric/titanium water heat pipe has been constructed and tested; it transported up to 60 W of power at about 390 K. Startup and operation both with and against gravity examined. Wick testing was begun to aid in the design and construction of an improved prototype heat pipe, with a 38-{mu}m stainless steel linear covered by a biaxially-braided Nextel (trademark of the 3M Co., St. Paul, Minnesota) sleeve that is approximately 300-{mu}m thick. Wick testing took place in 1-g; limited testing in 0-g was initiated, and results to date suggest that in 0-g, wick performance improves over that in 1-g.
Date: July 1991
Creator: Antoniak, Z.I.; Webb, B.J.; Bates, J.M.; Cooper, M.F. & Pauley, K.A.
Partner: UNT Libraries Government Documents Department

1.2 MW klystron for Asymmetric Storage Ring B Factory

Description: A cw klystron operating at 476 MHz has been developed jointly by SLAC and Varian Associates. The unique set of characteristics of this tube were strongly guided by requirements of the fast feedback necessary to prevent oscillations of the storage ring beams caused by the detuned accelerating cavity. This requires a combination of bandwidth and short group delay within the klystron. The RF feedback stabilization scheme also requires amplitude modulation making it necessary to operate the klystron about 10% below saturation. Performance specifications and initial operating results are presented.
Date: March 1995
Creator: Fowkes, W. R.; Caryotakis, G. & Doyle, E.
Partner: UNT Libraries Government Documents Department

1/2/Sup +/. -->. 1/2/Sup -/ Beta Decay of /Sup 19/Ne and the Parity Nonconserving Nn Force

Description: A branching ratio of (1.20 +- 0.20) x 10/sup -4/ is obtained for the ..beta../sup +/ decay of /sup 19/Ne to the 110 keV 1/2/sup -/ level of /sup 19/F. This transition (presumably dominated by the ..delta..J/sup ..pi../ = 0/sup -/ axial charge operator) provides a crucial test of wavefunctions used in interpreting the parity mixing of the ground and 110 keV levels of /sup 19/F. These wavefunctions, which yield a parity mixing larger than that observed experimentally, also predict too large a ..beta../sup +/ decay rate.
Date: 1978~
Creator: Adelberger, E. G.; Hindi, M. M.; Hoyle, C. D.; Swanson, H. E. & Von Lintig, R. D.
Partner: UNT Libraries Government Documents Department

1 & 2 Thessalonians in the Lamkang Language

Description: Lamkang translation of the New Testament books of First and Second Thessalonians from the Bible. Translated into Lamkang by Tholung Daniel along with the other consultants of Lamkang.
Access: Restricted to the UNT Libraries and requires authentication.
Date: 2014
Creator: Evangel Bible Translators
Partner: UNT College of Information

1.4 Natural Gas Combustion

Description: This document focus's on the use of natural gas as a major combustion fuel and offers information on firing practices, emissions, and controls.
Date: 1998
Creator: United States. Environmental Protection Agency.
Partner: UNT Libraries Government Documents Department

A 1.5 GeV compact light source with superconducting bending magnets

Description: This paper describes the design of a compact electron synchrotron light source for producing X-rays for medical imaging, protein crystallography, nano-machining and other uses up to 35 keV. The source will provide synchrotron light from six 6.9 tesla superconducting 60{degree} bending magnet stations. In addition the ring, contains conventional quadrupoles and sextupoles. The light source has a circumference of 26 meters, which permits it to be located in a variety of industrial and medical facilities.
Date: May 1995
Creator: Garren, A. A.; Cline, D. B.; Kolonko, J. J.; Green, M. A.; Johnson, D. E.; Leung, E. M. et al.
Partner: UNT Libraries Government Documents Department

1.5 megawatt dc chopper power supplies for plasma shape control on Doublet III

Description: The Doublet III device is designed to study noncircular plasmas, including doublet and dee-shaped cross-sections. The plasma shape is determined by a system of 24 field-shaping coils which surround the vacuum vessel. Control of the magnetic flux linking these coils allows the plasma shape to be varied and controlled. This paper describes the high-speed dc chopper which is a major component of the field-shaping coil power system. The high-speed dc choppers, with a frequency response of up to 5 kHz and a switching power capability of 1.5 megawatts are used for fine tuning and feedback control of the plasma position and shape. The design and operation of two 1.5 megawatt, 3 kHz choppers used on closed loop plasma control experiments will be presented.
Date: November 1979
Creator: Rock, P. J. & Wesley, J. C.
Partner: UNT Libraries Government Documents Department

1/12-scale physical modeling experiments in support of tank 241-SY- 101 hydrogen mitigation. Final report

Description: Hanford tank 241-SY-101 is a 75-ft-dia double-shell tank that contains approximately 1.1 M gal of radioactive fuel reprocessing waste. Core samples have shown that the tank contents are separated into two main layers, a article laden supernatant liquid at the top of the tank and a more dense slurry on the bottom. Two additional layers may be present, one being a potentially thick sludge lying beneath the slurry at the bottom of the tank and the other being the crust that has formed on the surface of the supernatant liquid. The supernatant is more commonly referred to as the convective layer and the slurry as the non-convective layer. Accumulation of gas (partly hydrogen) in the non-convective layer is suspected to be the key mechanism behind the gas burp phenomena, and several mitigation schemes are being developed to encourage a more uniform gas release rate (Benegas 1992). To support the full-scale hydraulic mitigation test, scaled experiments were performed to satisfy two objectives: 1. provide an experimental database for numerical- model validation; 2. establish operating parameter values required to mobilize the settled solids and maintain the solids in suspension.
Date: January 1993
Creator: Fort, J. A.; Bamberger, J. A.; Bates, J. M.; Enderlin, C. W. & Elmore, M. R.
Partner: UNT Libraries Government Documents Department

1/12-Scale scoping experiments to characterize double-shell tank slurry uniformity: Test plan

Description: Million gallon double-shell tanks (DSTs) at Hanford are used to store transuranic, high-level, and low-level wastes. These wastes generally consist of a large volume of salt-laden solution covering a smaller volume of settled sludge primarily containing metal hydroxides. These wastes will be retrieved and processed into immobile waste forms suitable for permanent disposal. The current retrieval concept is to use submerged dual-nozzle pumps to mobilize the settled solids by creating jets of fluid that are directed at the tank solids. The pumps oscillate, creating arcs of high-velocity fluid jets that sweep the floor of the tank. After the solids are mobilized, the pumps will continue to operate at a reduced flow rate sufficient to maintain the particles in a uniform suspension. The objectives of these 1/12-scale scoping experiments are to determine how Reynolds number, Froude number, and gravitational settling parameter affect the degree of uniformity achieved during jet mixer pump operation in the full-scale double-shell tanks; develop linear models to predict the degree of uniformity achieved by jet mixer pumps operating in the full-scale double-shell tanks; apply linear models to predict the degree of uniformity that will be achieved in tank 241-AZ-101 and determine whether contents of that tank will be uniform to within {+-} 10% of the mean concentration; and obtain experimental concentration and jet velocity data to compared with the TEMPEST computational and modeling predictions to guide further code development.
Date: October 1994
Creator: Bamberger, J. A. & Liljegren, L. M.
Partner: UNT Libraries Government Documents Department

AZ 01-14

Description: This abstract painting is predominately white with green, pink and gray vertical strokes broken by an implied horizontal line.
Date: 2001
Creator: Falsetta, Vincent
Partner: UNT College of Visual Arts + Design


Description: Haris XANTHOUDAKIS: 1 ... 789 It is the setting to music (of the "setting in rhythm", more precisely) of two Greek texts talking about the French revolution and illustrating two opposite aspects of its impact in Greece, still occupied by the Turks, of the end of the seventeenth century: a "Patriarchal letter" (sort of circular of the Patriarch of Constantinople, to read in the Orthodox churches), condemning the French who "practiced the fraticide, killed their king and lost their faith in God" (in this order) and, on the other hand, a poem by Antonios Martelaos (1754-1818), congratulating the French for having shed blood for the freedom of the people. The first text is played at the beginning and end of the song (phonetically reversed and in a normal voice, respectively). The other forms slowly, parallel to a rhythmic accompaniment, of "disco" nature. This double reconstitution will be done in steps of proportion 1: 2: 3: ...: 7: 8: 9. A portion of this proportion, namely 1: 7: 8: 9, serves to generate an interval pattern (semitone, fifth, sixth minor, sixth major) that appears in both its sequential and simultaneous forms. Repetitive music, "disco" music, serial music, for a piece that wants to celebrate a bicentennial, its contradictory way, while keeping its distance.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: 1989
Creator: Xanthoudakēs, Charēs
Partner: UNT Music Library

1-D Equilibrium Discrete Diffusion Monte Carlo

Description: We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-equilibrium diffusion, where it could be simultaneously coupled to Monte Carlo transport.
Date: August 2000
Creator: Evans, T. M.; Urbatsch, T. J. & Lichtenstein, H.
Partner: UNT Libraries Government Documents Department

1-GeV Linac Upgrade Study at Fermilab

Description: A linac injector for a new proton source complex at Fermilab is assumed to have a kinetic energy of 1 GeV. This linac would be sized to accelerate 100 mA of H{sup -} beam in a 200 microsecond pulse at a 15 Hz repetition rate. This would be adequate to produce {approximately}10{sup 14} protons per pulse allowing for future improvements of the new proton source complex. An alternate proposal is to add 600 MeV of side coupled cavity linac at 805 MHz to the existing 400 MeV Linac. This addition may either be in a new location or use the present Booster tunnel. A discussion of these possibilities will be given.
Date: September 1998
Creator: Popovic, M.; Moretti, A.; Noble, R. & Schmidt, C. W.
Partner: UNT Libraries Government Documents Department