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open access

Extracting Short Rise-Time Velocity Profiles with Digital Down-Shift Analysis of Optically Up-Converted PDV Data

Description: This work describes the digital down-shift (DDS) technique, a new method of extracting short rise-time velocity profiles in the analysis of optically up-converted PDV data. The DDS technique manipulates the PDV data by subtracting a constant velocity (i.e., the DDS velocity νDDS) from the velocity profile. DDS exploits the simple fact that the optically up-converted data ride on top of a base velocity (ν0, the apparent velocity at no motion) with a rapid rise to a high velocity (νf) of a few k… more
Date: September 8, 2010
Creator: Abel Diaz, Nathan Riley, Cenobio Gallegos, Matthew Teel, Michael Berninger, Thomas W. Tunnell
Item Type: Refine your search to only Article
open access

Liquid Effluent Monitoring Information System (LEMIS) test plans release 1.1

Description: The Liquid Effluent Monitoring Information System (LEMIS) is being developed as the organized information repository facility in support of the liquid effluent monitoring requirements of the Tri-Party Agreement. It is necessary to provide an automated repository into which the results from liquid effluent sampling will be placed. This repository must provide for effective retention, review, and retrieval of selected sample data by authorized persons and organizations. This System Architecture d… more
Date: September 8, 1994
Creator: Adams, R. T.
Item Type: Refine your search to only Report
open access

Bendable X-ray Optics at the ALS: Design, Tuning, Performance and Applications

Description: We review the development at the Advanced Light Source (ALS) of bendable x-ray optics widely used for focusing of beams of soft and hard x-rays. Typically, the focusing is divided in the tangential and sagittal directions into two elliptically cylindrical reflecting elements, the so-called Kirkpatrick-Baez (KB) pair [1]. Because fabrication of elliptical surfaces is complicated, the cost of directly fabricated tangential elliptical cylinders is often prohibitive. This is in contrast to flat opt… more
Date: September 8, 2008
Creator: Advanced Light Source, Lawrence Berkeley National Laboratory; Yashchuk, Valeriy V.; Church, Matthew N.; Knight, Jason W.; Kunz, Martin; MacDowell, Alastair A. et al.
Item Type: Refine your search to only Article
open access

Cosmic Ray Interactions in Shielding Materials

Description: This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth’s surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that wil… more
Date: September 8, 2011
Creator: Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J. & Troy, Meredith D.
Item Type: Refine your search to only Report
open access

Gas-to-liquids synthetic fuels for use in fuel cells : reformability, energy density, and infrastructure compatibility.

Description: The fuel cell has many potential applications, from power sources for electric hybrid vehicles to small power plants for commercial buildings. The choice of fuel will be critical to the pace of its commercialization. This paper reviews the various liquid fuels being considered as an alternative to direct hydrogen gas for the fuel cell application, presents calculations of the hydrogen and carbon dioxide yields from autothermal reforming of candidate liquid fuels, and reports the product gas com… more
Date: September 8, 1999
Creator: Ahmed, S.; Kopasz, J. P.; Russell, B. J. & Tomlinson, H. L.
Item Type: Refine your search to only Article
open access

Irradiation of Nd-Fe-B permanent magnets with APS bending magnet x-rays and {sup 60}Co {gamma}-rays

Description: The Advanced Photon Source (APS), as well as other third-generation synchrotron light sources, uses permanent magnets in the insertion devices to produce x-rays for scientific research. When placed in a high-energy storage ring, these permanent magnets are subjected to irradiation from synchrotron radiation, high-energy bremsstrahlung, and bremsstrahlung-produced photoneutrons. Previous investigations have exhibited varying degrees of degradation in the intensity of magnetization of these magne… more
Date: September 8, 2000
Creator: Alderman, J.; Job, P. K. & Puhl, J.
Item Type: Refine your search to only Report
open access

Precision Electroweak Measurements on the Z Presonance

Description: The authors report on the final electroweak measurements performed with data taken at the Z resonance by the experiments operating at the electron-positron colliders SLC and LEP. the data consist of 17 million Z decays accumulated by the ALEPH, DELPHI, L3 and OPAL experiments at LEP, and 600 thousand Z decays by the SLD experiment using a polarized beam at SLC. The measurements include cross-sections, forward-backward asymmetries and polarized asymmetries. The mass and width of the Z boson, m{s… more
Date: September 8, 2005
Creator: Aleph,Delphi,L3,Opal,SLD , Collaborations
Item Type: Refine your search to only Report
open access

The 2010 Oil Spill: Natural Resource Damage Assessment Under the Oil Pollution Act

Description: The 2010 Deepwater Horizon oil spill leaked an estimated 4.1 million barrels of oil into the Gulf of Mexico, damaging the waters, shores, and marshes, and the fish and wildlife that live there. When resources in the public trust are harmed by contamination, federal, state, foreign, and tribal governments may seek compensation for damage to natural resources under certain laws. This is done in two steps: first, by assessing the harm; then, by determining how and what restoration will take place.… more
Date: September 8, 2010
Creator: Alexander, Kristina
Item Type: Refine your search to only Report
open access

Smart Screening System (S3) In Taconite

Description: The conventional screening machines used in processing plants have had undesirable high noise and vibration levels. They also have had unsatisfactorily low screening efficiency, high energy consumption, high maintenance cost, low productivity, and poor worker safety. These conventional vibrating machines have been used in almost every processing plant. Most of the current material separation technology uses heavy and inefficient electric motors with an unbalanced rotating mass to generate the s… more
Date: September 8, 2006
Creator: Allaei, Daryoush
Item Type: Refine your search to only Report
open access

Pumping Characteristics for Several Simulated Variable-Geometry Ejectors With Hot and Cold Primary Flow

Description: Report presenting an investigation of the pumping characteristics of eight conical ejectors mounted on a fuselage portion of a supersonic airplane. The diameter ratio, spacing ratio, nozzle pressure, and ejector weight flows were varied. Results regarding the ejector pumping characteristics, comparison with previous results, comparison of data for cold and hot primary flow, and ejector air-supply requirements are provided.
Date: September 8, 1954
Creator: Allen, John L.
Item Type: Refine your search to only Report
open access

Pumping Characteristics for Several Simulated Variablegeometry Ejectors With Hot and Cold Primary Flow

Description: Report presenting an investigation of the pumping characteristics of eight conical ejectors mounted on a scale fuselage portion of a supersonic airplane. The configurations simulated various positions of a two-position nozzle with a fixed shroud and double-iris exit. Results regarding ejector pumping characteristics, comparison with previous results, comparison of data for cold and hot primary flow, and ejector air-supply requirements are provided.
Date: September 8, 1954
Creator: Allen, John L.
Item Type: Refine your search to only Report
open access

Using Artificial Neural Networks to Assess Microbial Communities

Description: We are evaluating artificial neural networks (ANNs) as tools for assessing changes in soil microbial communities following exposure to metals. We analyzed signature lipid biomarker data collected from two soil microcosm experiments using an autoassociative ANN. In one experiment, the microcosms were exposed to O, 100, or 250 ppm of metals, and in the other experiment the microcosms were exposed to O or 500 ppm of metals. The ANNs were able to distinguish between microcosms exposed and not expos… more
Date: September 8, 1998
Creator: Almeida, J. S.; Brand, C. C.; Palumbo, A. V.; Pfiffner, S. M. & Schryver, J. C.
Item Type: Refine your search to only Article
open access

Microarcsecond relative astrometry from the ground with a diffractive pupil

Description: The practical use of astrometry to detect exoplanets via the reflex motion of the parent star depends critically on the elimination of systematic floors in imaging systems. In the diffractive pupil technique proposed for space-based detection of exo-earths, extended diffraction spikes generated by a dotted primary mirror are referenced against a wide-field grid of background stars to calibrate changing optical distortion and achieve microarcsecond astrometric precision on bright targets (Guyon … more
Date: September 8, 2011
Creator: Ammons, S. Mark; Bendek, Eduardo A. & Guyon, Olivier
Item Type: Refine your search to only Article
open access

Electronic and magnetic structure of GaxFe1-x thin films

Description: The electronic as well as magnetic properties of Ga{sub x}Fe{sub 1-x} films were studied by soft x-ray measurements. Using x-ray magnetic circular dichroism the Fe majority-spin band was found to be completely filled for x {approx} 0.3. With further enhanced Ga content, the Fe moment as well as the angular dependence of the x-ray magnetic linear dichroism decrease strongly, which we attribute to the formation of D0{sub 3} precipitates. Moreover, the magnetocrystalline anisotropy drops significa… more
Date: September 8, 2010
Creator: Arenholz, E.; van der Laan, G.; McClure, A. & Idzerda, Y.
Item Type: Refine your search to only Article
open access

The Debt Limit: History and Recent Increases

Description: This report discusses how the total debt of the federal government can increase, an historical overview of debt limits, and how the current economic slowdown has led to higher deficits and thereby a series of debt limit increases, as well as legislation related to these increases.
Date: September 8, 2010
Creator: Austin, D. Andrew & Levit, Mindy R.
Item Type: Refine your search to only Report
open access

Effects of Fire on Soil Seed Banks on the Hanford Site

Description: The Hanford wildfire in the summer of 2000 destroyed much of the vegetation on the Hanford Site, often resulting in soil erosion and dust storms. The 200 W Area has been affected by dust storms, and a re-vegetation project has been planned for the area to the west, the source of much of the dust. To determine if the seed bank in this area had been damaged by the fire, inhibiting natural re-growth, soil samples were collected from three burned areas and watered to see how much seedling emergence… more
Date: September 8, 2000
Creator: Baker, Sarah E.
Item Type: Refine your search to only Report
open access

High-temperature internal oxidation of Ag/1.2at.% Mg and Ag/0.25at.% Mg-0.25at.% Ni.

Description: High-temperature oxygen diffusion and internal oxidation in Ag, Ag/1.2 at.% Mg (Ag-Mg), and Ag/0.25 at.% Mg-0.25 at.% Ni (Ag-Mg-Ni) have been studied, mostly in air and 8% O{sub 2}, at 450-835 C. The focus of the studies was on thermogravimetric analysis, microhardness tests, and optical and electron microscopy observations of grain growth and its inhibition by oxidation. The internal oxidation of both alloys exhibited nearly identical activation energies (0.81 eV for Ag-Mg and 0.83 eV for Ag-M… more
Date: September 8, 1999
Creator: Balachandran, U.; Goretta, K. C.; McNallan, M. J.; Park, J.-H. & Prorok, B. C.
Item Type: Refine your search to only Article
open access

Impact of air-exposure on the chemical and electronic structure ofZnO:Zn3N2 thin films

Description: The chemical and electronic surface structure of ZnO:Zn3N2 ("ZnO:N") thin films with different N contents was investigated by soft x-ray emission spectroscopy. Upon exposure to ambient air (in contrast to storage in vacuum), the chemical and electronic surface structure of the ZnO:N films changes substantially. In particular, we find that the Zn3N2/(Zn3N2+ZnO) ratio decreases with exposure time and that this change depends on the initial N content. We suggest a degradation mechanism b… more
Date: September 8, 2008
Creator: Bar, M.; Ahn, K.-S.; Shet, S.; Yan, Y.; Weinhardt, L.; Fuchs, O. et al.
Item Type: Refine your search to only Article
open access

An MPI implementation of the SPAI preconditioner on the T3E

Description: The authors describe and test spai_1.1, a parallel MPIimplementation of the sparse approximate inverse (SPAI) preconditioner.They show that SPAI can be very effective for solving a set of very largeand difficult problems on a Cray T3E. The results clearly show the valueof SPAI (and approximate inverse methods in general) as the viablealternative to ILU-type methods when facing very large and difficultproblems. The authorsstrengthen this conclusion by showing that spai_1.1also has very good scal… more
Date: September 8, 1997
Creator: Barnard, Stephen T.; Bernardo, Luis M. & Simon, Horst D.
Item Type: Refine your search to only Article
open access

R. F. cavity design for synchrotron light source

Description: The cavity design for the large ring of the proposed synchrotron light source is being considered. It represents the worst case situation in all respects so that a similar design for the small ring will face no problems. Basic requirements are that the cavity provide a peak gap voltage of up to 500 kV at a frequency of 53.52 MHz. Sufficient tuning range must be provided to allow for the reactive detuning of the beam and also thermal changes. Provisions for phase and amplitude control of two cav… more
Date: September 8, 1978
Creator: Batchelor, K. & Claus, J.
Item Type: Refine your search to only Report
open access

CDF B spectroscopy results: B** and Bc{sup +}

Description: The authors report on two spectroscopy results from CDF. First, they observe the orbitally excited B** mesons in B {r_arrow} {ell}D(*) X events. They find 28 {+-} 6 {+-} 3% of light B mesons produced are B** states. A collective mass fit results in a B{sub 1} mass of 5.71 {+-} 0.02 GeV/c{sup 2}. Secondly, they observe 20.4{sub {minus}5.5}{sup +0.18} {+-} 0.03 ps lifetime. The production rate is in reasonable accordance with expectations.
Date: September 8, 1999
Creator: Bauer, G.
Item Type: Refine your search to only Article
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