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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 demonstrat… more
Date: April 1997
Creator: Baca, A. G.; Sherwin, M. E.; Zolper, J. C.; Shul, R. J.; Briggs, R. D.; Heise, J. A. et al.
Item Type: Refine your search to only Article
open access

A 1.8 K test facility for superconducting RF cavities

Description: To demonstrate the feasibility of superconducting RF technology for a high energy e{sup +}/e{sup {minus}} collider, a research and development program has begun with collaborators from Europe, Asia, and North America. The immediate goal of the R&D program is to build and operate a 50 meter-long linac at DESY with 1.3 GHz superconducting RF cavities at a temperature of 1.8 K - 2.0 K and an accelerating gradient of 15 MV/meter. The refrigeration for the test system at DESY initially will have a c… more
Date: April 1, 1994
Creator: Horlitz, G.; Knopf, U.; Lange, R.; Petersen, B.; Sellmann, D.; Trines, D. et al.
Item Type: Refine your search to only Article
open access

A 1-Joule laser for a 16-fiber injection system

Description: A 1-J laser was designed to launch light down 16, multi-mode fibers (400-{micro}m-core dia.). A diffractive-optic splitter was designed in collaboration with Digital Optics Corporation (DOC), and was delivered by DOC. Using this splitter, the energy injected into each fiber varied <1%. The spatial profile out of each fiber was such that there were no ''hot spots,'' a flyer could successfully be launched and a PETN pellet could be initiated. Preliminary designs of the system were driven by sy… more
Date: April 6, 2004
Creator: Honig, J.
Item Type: Refine your search to only Article
open access

1+ -n+ ECR Ion Source Development Test Stand

Description: A test stand for the investigation of 1+-n+ charge boosting using an ECR ion sources is currently being assembled at the Texas A&M Cyclotron Institute. The ultimate goal is to relate the charge-boosting of ions of stable species to possible charge-boosting of ions of radioactive species extracted from the diverse, low-charge-state ion sources developed for radioactive ion beams.
Date: April 7, 2006
Creator: May, Donald P.
Item Type: Refine your search to only Report
open access

2-D and 3-D Elastic Modeling with Shared Seismic Models

Description: Several elastic models, both 2-D and 3-D, are being built for use in calculating synthetic elastic seismic data. The models will be made available to the research community, along with the synthetic data that are being calculated from them. These shared models have been proposed or contributed by participants in a collaborative industry, national laboratory, and university research project. The purpose of the modeling is to provide synthetic data to better understand elastic wave propagation an… more
Date: April 30, 2002
Creator: House, L.; Marfurt, K. J.; Larsen, S. & Martin, G. S.
Item Type: Refine your search to only Article
open access

A 3-Axis Force Balanced Accelerometer Using a Single Proof-Mass

Description: This paper presents a new method for wideband force balancing a proof-mass in multiple axes simultaneously. Capacitive position sense and force feedback are accomplished using the same air-gap capacitors through time multiplexing. Proof of concept is experimentally demonstrated with a single-mass monolithic surface micromachined 3-axis accelerometer.
Date: April 1997
Creator: Lemkin, M.A.; Boser, B.E.; Auslander, D. & Smith, J.
Item Type: Refine your search to only Article
open access

A 3-D Model of Signaling and Transport Pathways in Epithelial Cells

Description: A 3-dimensional computer model was developed to simulate the spatial and chemical evolution of calcium ions inside an array of human epithelial kidney cells. This is a prototype model, intended to develop a methodology to incorporate much more complex interactions of metabolic and other processes within many types of cells and lead to increased ability to predict cellular responses to disease as well as to chemical and biological warfare situations. Preliminary tests of the model are described.
Date: April 1, 2005
Creator: Quong, Andrew A. & Westbrook, Charles K.
Item Type: Refine your search to only Report
open access

A 3-Dimensional discrete fracture network generator to examine fracture-matrix interaction using TOUGH2

Description: Water fluxes in unsaturated, fractured rock involve the physical processes occurring at fracture-matrix interfaces within fracture networks. Modeling these water fluxes using a discrete fracture network model is a complicated effort. Existing preprocessors for TOUGH2 are not suitable to generate grids for fracture networks with various orientations and inclinations. There are several 3-D discrete-fracture-network simulators for flow and transport, but most of them do not capture fracture-matrix… more
Date: April 9, 2003
Creator: Ito, Kazumasa & Yongkoo, Seol
Item Type: Refine your search to only Article
open access

3-dimensional wells and tunnels for finite element grids

Description: Modeling fluid, vapor, and air injection and extraction from wells poses a number of problems. The length scale of well bores is centimeters, the region of high pressure gradient may be tens of meters and the reservoir may be tens of kilometers. Furthermore, accurate representation of the path of a deviated well can be difficult. Incorporating the physics of injection and extraction can be made easier and more accurate with automated grid generation tools that incorporate wells as part of a bac… more
Date: April 1, 1996
Creator: Cherry, T.A.; Gable, C.W. & Trease, H.
Item Type: Refine your search to only Report
open access

4. International reservoir characterization technical conference

Description: This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The… more
Date: April 1997
Item Type: Refine your search to only Article
open access

A 5-cm dipole for the SSC-DE-1

Description: A 5cm SSC superconducting dipole that develops 6.6 tesla at 5790 A is proposed. The two layer magnet has 12% more transfer function than the present design as a result of using thin collars and close in'' iron. The thin collars provide precise positioning of the coils; they also provide minimum prestress (perhaps 2000 psi) as aid for magnet assembly. A welded skin around the iron provides the final prestress and shapes and the coil geometry. A prestressed aluminum bar placed between the vertica… more
Date: April 30, 1990
Creator: Caspi, S.
Item Type: Refine your search to only Report
open access

7-GeV Advanced Photon Source Conceptual Design Report

Description: During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of … more
Date: April 1, 1987
Item Type: Refine your search to only Report
open access

8-oxoguainine enhances bending of DNA that favors binding of glycosylases

Description: Molecular dynamics (MD) simulations were carried out on the DNA oligonucleotide GGGAACAACTAG:CTAGTTGTTCCC in its native form and with guanine in the central G19:C6 base pair replaced by 8-oxoguanine (8oxoG). A box of explicit water molecules was used for solvation and Na+ counterions were added to neutralize the system. The direction and magnitude of global bending were assessed by a technique used previously to analyze simulations of DNA containing a thymine dimer. The presence of 8oxoG did no… more
Date: April 23, 2003
Creator: Miller, John H.
Item Type: Refine your search to only Article
open access

12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments

Description: A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temp… more
Date: April 22, 2008
Creator: Kugland, N.; Constantin, C. G.; Niemann, C.; Neumayer, P.; Chung, H.; Doppner, T. et al.
Item Type: Refine your search to only Article
open access

16-APR-03 Final Release of ENDF/B-V for use with LLNL Codes

Description: The new data files were prepared in two steps. First, the ENDF/B-V database was translated to an ENDL-format ascii database. The ENDL ascii format is a point-wise tabular storage scheme where intermediate values are extracted via interpolation. Sufficient point-wise information was generated in the translation to insure an extraction tolerance of 0.1% for most of the data. The only exception is along the incident neutron energy axis of the outgoing particle energy probability density function w… more
Date: April 16, 2003
Creator: Hill, T S; McNabb, D P; Hedstrom, G W; Beck, B & Hagmann, C A
Item Type: Refine your search to only Report
open access

A 40 GByte/s read-out system for GEM

Description: The preliminary design of the read-out system for the GEM (Gammas, Electrons, Muons) detector at the Superconducting Super Collider is presented. The system reads all digitized data from the detector data sources at a Level 1 trigger rate of up to 100 kHz. A total read-out bandwidth of 40 GBytes/s is available. Data are stored in buffers that are accessible for further event filtering by an on-line, processor farm. Data are transported to the farm only as they are needed by the higher-level tri… more
Date: April 1994
Creator: Bowden, M.; Carrel, J.; Dorenbosch, J. & Kapoor, V.
Item Type: Refine your search to only Report
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