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(02.2) Scoping experiments; (02.3) long-term corrosion testing and properties evaluation of candidate waste package basket material

(02.2) Scoping experiments; (02.3) long-term corrosion testing and properties evaluation of candidate waste package basket material

Date: December 20, 1996
Creator: VanKonynenburg, R. A.
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.
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The 2.3 {angstrom} crystal structure of cholera toxin B subunit pentamer: Choleragenoid

The 2.3 {angstrom} crystal structure of cholera toxin B subunit pentamer: Choleragenoid

Date: February 1, 1996
Creator: Zhang, Rong-Guang; Westbrook, M.L.; Maulik, P.R.; Reed, R.A.; Shipley, G.; Westbrook, E.M. et al.
Description: Cholera toxin, a heterohexameric AB{sub 5} enterotoxin released by Vibrio cholera, induces a profuse secretory diarrhea in susceptible hosts. Choleragenoid, the B subunit pentamer of cholera toxin, directs the enzymatic A subunit to its target by binding to GM{sub 1} gangliosides exposed on the luminal surface of intestinal epithelial cells. We have solved the crystal structure of choleragenoid at 2.3 {Angstrom} resolution by combining single isomorphous replacement with non-crystallographic symmetry averaging. The structure of the B subunits, and their pentameric arrangement, closely resembles that reported for the intact holotoxin (choleragen), the heat-labile enterotoxin from E. coli, and for a choleragenoid-GM{sub 1} pentasaccharide complex. In the absence of the A subunit the central cavity of the B pentamer is a highly solvated channel. The binding of the A subunit or the receptor pentasaccharide to choleragenoid has only a modest effect on the local stereochemistry and does not perceptibly alter the subunit interface.
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2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

2.5 MHz feedforward beam loading compensation in the Fermilab Main Injector

Date: May 19, 2003
Creator: Dey, Joseph E.; Kourbanis, Ioanis & Steimel, James
Description: There are five 2.5 MHz ferrite cavities (h = 28) in the Main Injector with an R/Q of 500 that are presently used for coalescing for the Tevatron. For use with the Fermilab Recycler, feedforward (FF) beam loading compensation (BLC) is required on these cavities because they will be required to operate at a net of 2 kV. Under current Recycler beam conditions, the beam-induced voltage is of this order. Recently a system using a digital bucket delay module operating at 53 MHz (h = 588) was used to produce a one-turn-delay feedforward signal. This signal was then combined with the low level RF signal to the 2.5 MHz cavities to cancel the beam induced voltage. During current operation they have shown consistently to operate with over a 20 dB reduction in beam loading.
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The 2.6 Angstrom resolution structure of Rhodobacter capsulatus bacterioferritin with metal-free dinuclear site and heme iron in a crystallographic 'special position'

The 2.6 Angstrom resolution structure of Rhodobacter capsulatus bacterioferritin with metal-free dinuclear site and heme iron in a crystallographic 'special position'

Date: October 31, 2001
Creator: Cobessi, D.; Huang, L.-S.; Ban, M.; Pon, N.G.; Daldal, F. & Berry, E.A.
Description: No abstract prepared.
Contributing Partner: UNT Libraries Government Documents Department
A 2.14 ms candidate optical pulsar in SN1987A: Ten years after

A 2.14 ms candidate optical pulsar in SN1987A: Ten years after

Date: September 1, 1997
Creator: Middleditch, J.; Kristian, J.A.; Kunkel, W.E.; Hill, K.M. & Watson, R.D.
Description: We have monitored Supernova 1987A in optical/near-infrared bands from a few weeks following its birth until the present time in order to search for a pulsar remnant. We have found an apparent pattern of emission near the frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14 ms period on numerous occasions over the next four years in data taken with a variety of telescopes, data systems and detectors, at a number of ground- and space-based observatories. The sequence of detections of this signal from Feb. `92 through August `93, prior to its apparent subsequent fading, is highly improbable (< 10{sup -10} for any noise source). We also find evidence for modulation of the 2.14 ms period with a {approx}1,000 s period which, when taken with the high spindown of the source (2-3 x 10{sup -10} Hz/s), is consistent with precession and spindown via gravitational radiation of a neutron star with a non- axisymmetric oblateness of {approx}10{sup -6}, and an implied gravitational luminosity exceeding that of the Crab Nebula pulsar by ...
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2\beta + \gamma from B^0 to D^\mp K^0 \pi^\pm Decays at BaBar: aSimulation Study

2\beta + \gamma from B^0 to D^\mp K^0 \pi^\pm Decays at BaBar: aSimulation Study

Date: April 16, 2007
Creator: Polci, Francesco; Schune, Marie-Helene; Stocchi, Achille & /Orsay, LAL
Description: The authors present the results of a simulation study to perform the extraction of 2{beta} + {gamma} from B{sup 0} {yields} D{sup {-+}}K{sup 0}{pi}{sup {+-}} decays through a time-dependent Dalitz analysis of BaBar data.
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2-D and 3-D Elastic Modeling with Shared Seismic Models

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

Date: April 30, 2002
Creator: House, L.; Marfurt, K. J.; Larsen, S. & Martin, G. S.
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 and the effects of structural and stratigraphic complexities. The 2-D models are easier to design and change and synthetic calculations can be run relatively quickly in them. It will be possible to alter their layer properties and calculate time-lapse data sets from them. Field data will be available to accompany many of the 2-D models. 3-D models are more realistic, but more difficult to design and change. They also require considerably more computing resources to calculate synthetic data from them. A new 3-D model is being designed, and will be used for computing synthetic elastic data.
Contributing Partner: UNT Libraries Government Documents Department
2-D electric fields and drifts near the magnetic separatrix in divertor tokamaks

2-D electric fields and drifts near the magnetic separatrix in divertor tokamaks

Date: November 15, 1998
Creator: Mattor, N.; Porter, G. D.; Rognlien, T. D. & Ryutov, D. D.
Description: A 2-D calculation is presented for the transport of plasma in the edge region of a divertor tokamak solving continuity, momentum, and energy balance fluid equations. The model uses anomalous radial diffusion, including perpendicular ion momentum, and classical cross-field drifts transport. Parallel and perpendicular currents yield a self-consistent electrostatic potential on both sides of the magnetic separatrix. Outside the separatrix, the simulation extends to material divertor plates where the incident plasma is recycled as neutral gas and where the plate sheath and parallel currents dominate the potential structure. Inside the separatrix, various radial current terms - from viscosity, charge-exchange and poloidal damping, inertia, and {triangledown}B - contribute to the determining the potential. The model rigorously enforces cancellation of gyro-viscous and magnetization terms from the transport equations. The results emphasize the importance of E x B particle flow under the X-point which depends on the sign of the toroidal magnetic field. Radial electric field (E{sub y}) profiles at the outer midplane are small with weak shear when high L-mode diffusion coefficients are used and are large with strong shear when smaller H-mode diffusion coefficients are used. The magnitude and shear of the electric field (E{sub y}) is larger both when the ...
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2-D Finite Element Cable and Box IEMP Analysis

2-D Finite Element Cable and Box IEMP Analysis

Date: December 17, 1998
Creator: Scivner, G.J. & Turner, C.D.
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.
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2-D image segmentation using minimum spanning trees

2-D image segmentation using minimum spanning trees

Date: September 1995
Creator: Xu, Y. & Uberbacher, E. C.
Description: This paper presents a new algorithm for partitioning a gray-level image into connected homogeneous regions. The novelty of this algorithm lies in the fact that by constructing a minimum spanning tree representation of a gray-level image, it reduces a region partitioning problem to a minimum spanning tree partitioning problem, and hence reduces the computational complexity of the region partitioning problem. The tree-partitioning algorithm, in essence, partitions a minimum spanning tree into subtrees, representing different homogeneous regions, by minimizing the sum of variations of gray levels over all subtrees under the constraints that each subtree should have at least a specified number of nodes, and two adjacent subtrees should have significantly different average gray-levels. Two (faster) heuristic implementations are also given for large-scale region partitioning problems. Test results have shown that the segmentation results are satisfactory and insensitive to noise.
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2-D Imaging of Electron Temperature in Tokamak Plasmas

2-D Imaging of Electron Temperature in Tokamak Plasmas

Date: July 8, 2004
Creator: Munsat, T.; Mazzucato, E.; Park, H.; Domier, C. W.; Johnson, M.; Luhmann, N. C., Jr. et al.
Description: By taking advantage of recent developments in millimeter wave imaging technology, an Electron Cyclotron Emission Imaging (ECEI) instrument, capable of simultaneously measuring 128 channels of localized electron temperature over a 2-D map in the poloidal plane, has been developed for the TEXTOR tokamak. Data from the new instrument, detailing the MHD activity associated with a sawtooth crash, is presented.
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2-D linear motion system. Innovative technology summary report

2-D linear motion system. Innovative technology summary report

Date: November 1, 1998
Creator: unknown
Description: The US Department of Energy's (DOE's) nuclear facility decontamination and decommissioning (D and D) program requires buildings to be decontaminated, decommissioned, and surveyed for radiological contamination in an expeditious and cost-effective manner. Simultaneously, the health and safety of personnel involved in the D and D activities is of primary concern. D and D workers must perform duties high off the ground, requiring the use of manlifts or scaffolding, often, in radiologically or chemically contaminated areas or in areas with limited access. Survey and decontamination instruments that are used are sometimes heavy or awkward to use, particularly when the worker is operating from a manlift or scaffolding. Finding alternative methods of performing such work on manlifts or scaffolding is important. The 2-D Linear Motion System (2-D LMS), also known as the Wall Walker{trademark}, is designed to remotely position tools and instruments on walls for use in such activities as radiation surveys, decontamination, and painting. Traditional (baseline) methods for operating equipment for these tasks require workers to perform duties on elevated platforms, sometimes several meters above the ground surface and near potential sources of contamination. The Wall Walker 2-D LMS significantly improves health and safety conditions by facilitating remote operation of equipment. ...
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2-D Modeling of Energy-z Beam Dynamics Using the LiTrack Matlab Program

2-D Modeling of Energy-z Beam Dynamics Using the LiTrack Matlab Program

Date: December 15, 2005
Creator: Cauley, S.K.; /Unlisted; Woods, M. & /SLAC
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 ...
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2-D or not 2-D, that is the question: A Northern California test

2-D or not 2-D, that is the question: A Northern California test

Date: June 6, 2005
Creator: Mayeda, K; Malagnini, L; Phillips, W S; Walter, W R & Dreger, D
Description: Reliable estimates of the seismic source spectrum are necessary for accurate magnitude, yield, and energy estimation. In particular, how seismic radiated energy scales with increasing earthquake size has been the focus of recent debate within the community and has direct implications on earthquake source physics studies as well as hazard mitigation. The 1-D coda methodology of Mayeda et al. has provided the lowest variance estimate of the source spectrum when compared against traditional approaches that use direct S-waves, thus making it ideal for networks that have sparse station distribution. The 1-D coda methodology has been mostly confined to regions of approximately uniform complexity. For larger, more geophysically complicated regions, 2-D path corrections may be required. The complicated tectonics of the northern California region coupled with high quality broadband seismic data provides for an ideal ''apples-to-apples'' test of 1-D and 2-D path assumptions on direct waves and their coda. Using the same station and event distribution, we compared 1-D and 2-D path corrections and observed the following results: (1) 1-D coda results reduced the amplitude variance relative to direct S-waves by roughly a factor of 8 (800%); (2) Applying a 2-D correction to the coda resulted in up to 40% variance ...
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2-D Path Corrections for Local and Regional Coda Waves: A Test of Transportability

2-D Path Corrections for Local and Regional Coda Waves: A Test of Transportability

Date: July 13, 2005
Creator: Mayeda, K M; Malagnini, L; Phillips, W S; Walter, W R; Dreger, D S & Morasca, P
Description: Reliable estimates of the seismic source spectrum are necessary for accurate magnitude, yield, and energy estimation. In particular, how seismic radiated energy scales with increasing earthquake size has been the focus of recent debate within the community and has direct implications on earthquake source physics studies as well as hazard mitigation. The 1-D coda methodology of Mayeda et al. [2003] has provided the lowest variance estimate of the source spectrum when compared against traditional approaches that use direct S-waves, thus making it ideal for networks that have sparse station distribution. The 1-D coda methodology has been mostly confined to regions of approximately uniform complexity. For larger, more geophysically complicated regions, 2-D path corrections may be required. We will compare performance of 1-D versus 2-D path corrections in a variety of regions. First, the complicated tectonics of the northern California region coupled with high quality broadband seismic data provides for an ideal ''apples-to-apples'' test of 1-D and 2-D path assumptions on direct waves and their coda. Next, we will compare results for the Italian Alps using high frequency data from the University of Genoa. For Northern California, we used the same station and event distribution and compared 1-D and 2-D path ...
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A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media

A 2-D Pore-Network Model of the Drying of Single-Component Liquids in Porous Media

Date: January 20, 2000
Creator: Yortsos, Yanic C.; Yiotis, A. G.; Stubos, A. K. & Boundovis, A. G.
Description: The drying of liquid-saturated porous media is typically approaching using macroscopic continuum models involving phenomenological coefficients. Insight on these coefficients can be obtained by a more fundamental study at the pore- and pore-network levels. In this report, a model based on pore-network representation of porous media that accounts for various process at the pore-scale is presented. These include mass transfer by advection and diffusion in the gas phase, viscous flow in liquid and gas phases and capillary effects at the gas-liquid menisci in the pore throats.
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2-D Reflectometer Modeling for Optimizing the ITER Low-field Side Reflectometer System

2-D Reflectometer Modeling for Optimizing the ITER Low-field Side Reflectometer System

Date: September 2, 2005
Creator: Kramer, G.J.; Nazikian, R.; Valeo, E.J.; Budny, R.V.; Kessel, C. & Johnson, D.
Description: The response of a low-field side reflectometer system for ITER is simulated with a 2?D reflectometer code using a realistic plasma equilibrium. It is found that the reflected beam will often miss its launch point by as much as 40 cm and that a vertical array of receiving antennas is essential in order to observe a reflection on the low-field side of ITER.
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A 2-D Self-Consistent DSMC Model for Chemically Reacting Low Pressure Plasma Reactors

A 2-D Self-Consistent DSMC Model for Chemically Reacting Low Pressure Plasma Reactors

Date: June 17, 1999
Creator: Bartel, Timothy J.; Economou, Demetre & Johannes, Justine E.
Description: This paper will focus on the methodology of using a 2D plasma Direct Simulation Monte Carlo technique to simulate the species transport in an inductively coupled, low pressure, chemically reacting plasma system. The pressure in these systems is typically less than 20 mtorr with plasma densities of approximately 10{sup 17} {number_sign}/m{sup 3} and an ionization level of only 0.1%. This low ionization level tightly couples the neutral, ion, and electron chemistries and interactions in a system where the flow is subsonic. We present our strategy and compare simulation results to experimental data for Cl{sub 2} in a Gaseous Electronics Conference (GEC) reference cell modified with an inductive coil.
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2-D Simulations of Drainage Winds and Diffusion Compared to Observations

2-D Simulations of Drainage Winds and Diffusion Compared to Observations

Date: May 29, 2001
Creator: Garrett, A. J.
Description: A vertically integrated dynamical drainage flow model is developed from conservation equations for momentum and mass in a terrain-following coordinate system. Wind fields from the dynamical model drive a Monte Carlo transport and diffusion model. The model needs only topographic data, an Eulerian or Lagrangian time scale and a surface drag coefficient for input data, and can be started with a motionless atmosphere. Model wind and diffusion predictions are compared to observations from the rugged Geysers CA area. Model winds generally agree with observed surface winds, and in some cases may give better estimates of area-averaged flow than point observations. Tracer gas concentration contours agree qualitatively with observed contours, and point predictions of maximum concentrations were correctly predicted to within factors of 2 to 10. Standard statistical tests of model skill showed that the accuracy of the predictions varied significantly from canyon to canyon in the Geysers are a. Model wind predictions are also compared to observations from the Savannah River Plant of SC which has gently rolling terrain. The model correctly simulated the slower development of drainage winds and slower deepening of the drainage layer in the Savannah River Valley, relative to the Geysers CA simulations. The SC simulations ...
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2-Fold G.M. Coincidence Unit

2-Fold G.M. Coincidence Unit

Date: 1947
Creator: U.S. Atomic Energy Commission
Description: Report containing a diagram of a coincidence unit, outlining resistor values and other technical specifications.
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A 2-GHz Rectangular Corrugated Horn

A 2-GHz Rectangular Corrugated Horn

Date: October 1, 1991
Creator: Bersanelli, M.; Bensadoun, M.; De Amici, Giovanni; Limon, M.; Smoot, George F.; Tanaka, S. et al.
Description: We have designed, constructed and tested a large, rectangular horn antenna with a center frequency of 2.0 GHz, corrugated on the E-plane walls, made out of aluminum sheet. A new technique has been developed to solder thin aluminum strips onto the back plane to form the corrugations. The radiation beam pattern shows half-power beamwidths of 12{sup 0} and 14{sup 0} in the H and E planes respectively, and side lobe response below -40 dB at angles greater than 50{sup 0} from horn axis. The measured return loss is less than -20 dB (VSWR &lt; 1.22) between 1.7 and 2.3 GHz; insertion loss is less than 0.15 dB.
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2 HZ, 30 T SPLIT PULSE WATER COOLED MAGNET FOR NEUTRON SCATTERING EXPERIMENTS (MATERIALS CHARACTERIZATION AND DESIGN OPTIONS)

2 HZ, 30 T SPLIT PULSE WATER COOLED MAGNET FOR NEUTRON SCATTERING EXPERIMENTS (MATERIALS CHARACTERIZATION AND DESIGN OPTIONS)

Date: August 26, 1997
Creator: EYSSA, Y. M.; WALSH, R. P.; MILLER, J. R.; MILLER, G. E.; PERNAMBUCO-WISE, P.; BIRD, M. D. et al.
Description: No abstract prepared.
Contributing Partner: UNT Libraries Government Documents Department
2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade

2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade

Date: July 30, 2005
Creator: unknown
Description: Community Correspondence - 2 Letters from concerned citizens in response to the recommendation regarding the Defense Office of Hearings and Appeals in Fort Meade
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2-MV electrostatic quadrupole injector for heavy-ion fusion

2-MV electrostatic quadrupole injector for heavy-ion fusion

Date: November 10, 2004
Creator: Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan, J.W.; Prost, L. & Seidl, P.A.
Description: High current and low emittance are principal requirements for heavy-ion injection into a linac driver for inertial fusion energy. An electrostatic quadrupole (ESQ) injector is capable of providing these high charge density and low emittance beams. We have modified the existing 2-MV Injector to reduce beam emittance and to double the pulse length. We characterize the beam delivered by the modified injector to the High Current Transport Experiment (HCX) and the effects of finite rise time of the extraction voltage pulse in the diode on the beam head. We demonstrate techniques for mitigating aberrations and reducing beam emittance growth in the injector.
Contributing Partner: UNT Libraries Government Documents Department