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Monitoring the chemistry and materials of the Magma Geothermal Binary Cycle Generating Plant

Description: The Magma Binary Cycle Plant at the East Mesa KGRA is the first geothermal generating plant of its kind in the US. In cooperation with the Magma Electric Company, the Pacific Northwest Laboratory conducted a DOE sponsored program at the plant to document the chemistry and materials performance during the first two years of operation. This paper describes the methods used, the instruments and the results.
Date: October 8, 1982
Creator: Shannon, Donald W.
Partner: UNT Libraries Government Documents Department
open access

Defects in p-GaN and their atomic structure

Description: In this paper defects formed in p-doped GaN:Mg grown with Ga polarity will be discussed. The atomic structure of these characteristic defects (Mg-rich hexagonal pyramids and truncated pyramids) in bulk and thin GaN:Mg films grown with Ga polarity was determined at atomic resolution by direct reconstruction of the scattered electron wave in a transmission electron microscope. Small cavities were present inside the defects. The inside walls of the cavities were covered by GaN which grew with reve… more
Date: October 8, 2004
Creator: Liliental-Weber, Z.; Tomaszewicz, T.; Zakharov, D.; Jasinski, J. & and O'Keefe, M.
Partner: UNT Libraries Government Documents Department
open access

PROCEEDINGS OF RIKEN BNL RESEARCH CENTER WORKSHOP ENTITLED "GLOBAL ANALYSIS OF POLARIZED PARTON DESTRIBUTIONS IN THE RHIC ERA" (VOLUME 86).

Description: The determination of the polarized gluon distribution is a central goal of the RHIC spin program. Recent achievements in polarization and luminosity of the proton beams in RHIC, has enabled the RHIC experiments to acquire substantial amounts of high quality data with polarized proton beams at 200 and 62.4 GeV center of mass energy, allowing a first glimpse of the polarized gluon distribution at RHIC. Short test operation at 500 GeV center of mass energy has also been successful, indicating abse… more
Date: October 8, 2007
Creator: DESHPANDE,A. & VOGELSANG, W.
Partner: UNT Libraries Government Documents Department
open access

Amplification of an ultra short pulse laser by stimulated Raman scattering of a 1 ns pulse in a low density plasma

Description: Experiments are described in which a 1mJ, 1ps, 1200 nm seed laser beam is amplified by interaction with an intersecting 350 J, 1ns, 1054 nm pump beam in a low density (1 x 10{sup 19}/cm{sup 3}) plasma. The transmission of the seed beam is observed to be enhanced by > {approx} 25 x when the plasma is near the resonant density for stimulated Raman scattering (SRS), compared to measured transmissions at wavelengths just below the resonant value. The amplification is observed to increase rapidly… more
Date: October 8, 2007
Creator: Kirkwood, R. K.; Dewald, E.; Niemann, C.; Meezan, N.; Wilks, S. C.; Price, D. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Low-level-signal data acquisition for the MFTF superconducting-magnet system

Description: Acquisition of low level signals from sensors mounted on the superconducting yin-yang magnet in the Mirror Fusion Test Facility (MFTF) imposes very strict requirements on the magnet signal conditioning and data acquisition system. Of the various types of sensors required, thermocouples, strain gages, and voltage taps produce very low level outputs. These low level outputs must be accurately measured in the harsh environment of slowly varying magnetic fields, cryogenic temperatures, high vacuum,… more
Date: October 8, 1981
Creator: Montoya, C.R.
Partner: UNT Libraries Government Documents Department
open access

Tip-tilt compensation: Resolution limits for ground-based telescopes using laser guide star adaptive optics. Revision 2

Description: The angular resolution of long-exposure images from ground-based telescopes equipped with laser guide star adaptive optics systems is fundamentally limited by the the accuracy with which the tip-tilt aberrations introduced by the atmosphere can be corrected. Assuming that a natural star is used as the tilt reference, the residual error due to tilt anisoplanatism can significantly degrade the long-exposure resolution even if the tilt reference star is separated from the object being imaged by a … more
Date: October 8, 1992
Creator: Olivier, S. S.; Max, C. E.; Gavel, D. T. & Brase, J. M.
Partner: UNT Libraries Government Documents Department
open access

Field and Current Amplification in the SSPX Spheromak

Description: Results are presented from experiments relating to magnetic field generation and current amplification in the SSPX spheromak. The SSPX spheromak plasma is driven by DC coaxial helicity injection using a 2MJ capacitor bank. Peak toroidal plasma currents of up to 0.7MA and peak edge poloidal fields of 0.3T are produced; lower current discharges can be sustained up to 3.5msec. When edge magnetic fluctuations are reduced below 1% by driving the plasma near threshold, it is possible to produce plasm… more
Date: October 8, 2002
Creator: Hill, D. N.; Blumer, R. H.; Cohen, B. I.; Hooper, E. B.; McLean, H. S.; Moller, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Recent Advances in Indirect Drive ICF Target Physics

Description: In preparation for ignition on the National Ignition Facility, the Lawrence Livermore National Laboratory's Inertial Confinement Fusion Program, working in collaboration with Los Alamos National Laboratory, Commissariat a lEnergie Atomique (CEA), and Laboratory for Laser Energetics at the University of Rochester, has performed a broad range of experiments on the Nova and Omega lasers to test the fundamentals of the NIF target designs. These studies have refined our understanding of the importan… more
Date: October 8, 2002
Creator: Hammel, B.; Lindl, J.; Amendt, P. A.; Bernat, G. W.; Collins, G. W.; Glenzer, S. H. et al.
Partner: UNT Libraries Government Documents Department
open access

The Importance of High Temporal Resolution in Modeling Renewable Energy Penetration Scenarios

Description: Traditionally, modeling investment and dispatch problems in electricity economics has been limited by computation power. Due to this limitation, simplifications are applied. One common practice, for example, is to reduce the temporal resolution of the dispatch by clustering similar load levels. The increase of intermittent electricity from renewable energy sources (RES-E) changes the validity of this assumption. RES-E already cover a certain amount of the total demand. This leaves an increasing… more
Date: October 8, 2010
Creator: Nicolosi, Marco; Mills, Andrew D & Wiser, Ryan H
Partner: UNT Libraries Government Documents Department
open access

Electron-Cloud Build-Up: Theory and Data

Description: We present a broad-brush survey of the phenomenology, history and importance of the electron-cloud effect (ECE). We briefly discuss the simulation techniques used to quantify the electron-cloud (EC) dynamics. Finally, we present in more detail an effective theory to describe the EC density build-up in terms of a few effective parameters. For further details, the reader is encouraged to refer to the proceedings of many prior workshops, either dedicated to EC or with significant EC contents, incl… more
Date: October 8, 2010
Creator: Furman, M. A.
Partner: UNT Libraries Government Documents Department
open access

Semi-automated x-ray gauging process control system. [For pressed-material components]

Description: An x-ray gauging method was developed and a production gauging system was subsequently fabricated to control the quality of precision manufactured components. The gauging system measures via x-ray absorption the density of pressed finely divided solids held in a dissimilar container. The two dissimilar materials condition necessitated a ''two scan'' technique: first, the x-ray attenuation (absorption) of the empty container prior to loading and then, the attenuation of the loaded container are … more
Date: October 8, 1976
Creator: Draut, C. F. & Homan, D. A.
Partner: UNT Libraries Government Documents Department
open access

Turbulent energy generated by accelerations and shocks

Description: The turbulent energy generated at the interface between two fluids undergoing a constant acceleration or a shock is calculated. Assuming linear density profiles in the mixed region we find E/sub turbulent//E/sub directed/ = 2.3A/sup 2/% (constant acceleration) and 9.3A/sup 2/% (shock), where A is the Atwood number. Diffusion models predict somewhat less turbulent energy and a density profile with a tail extending into the lower density fluid. Eddy sizes are approximately 27% (constant accelerat… more
Date: October 8, 1986
Creator: Mikaelian, Karnig O.
Partner: UNT Libraries Government Documents Department
open access

Observation of relativistic effects in collective Thomson scattering

Description: We observe relativistic modifications to the Thomson scattering spectrum in a traditionally classical regime: v{sub osc}/c = eE{sub 0}/cm{omega}{sub 0} << 1 and T{sub e} < 1 keV. The modifications result from scattering off electron-plasma fluctuations with relativistic phase velocities. Normalized phase velocities v/c between 0.03 and 0.12 have been achieved in a N{sub 2} gas-jet plasma by varying the plasma density from 3 x 10{sup 18} cm{sup -3} to 7 x 10{sup 19} cm{sup -3} and elect… more
Date: October 8, 2009
Creator: Ross, J S; Glenzer, S H; Palastro, J P; Pollock, B B; Price, D; Divol, L et al.
Partner: UNT Libraries Government Documents Department
open access

A CW normal-conductive RF gun for free electron laser and energy recovery linac applications

Description: Currently proposed energy recovery linac and high average power free electron laser projects require electron beam sources that can generate up to {approx} 1 nC bunch charges with less than 1 mmmrad normalized emittance at high repetition rates (greater than {approx} 1 MHz). Proposed sources are based around either high voltage DC or microwave RF guns, each with its particular set of technological limits and system complications. We propose an approach for a gun fully based on mature RF and mec… more
Date: October 8, 2008
Creator: Baptiste, Kenneth; Corlett, John; Kwiatkowski, Slawomir; Lidia, Steven; Qiang, Ji; Sannibale, Fernando et al.
Partner: UNT Libraries Government Documents Department
open access

X-ray absorption spectroscopy at the Ni-K edge in Stackhousia tryonii Bailey hyperaccumulator

Description: Young plants of Stackhousia tryonii Bailey were exposed to 34 mM Ni kg-1 in the form of NiSO4- 6H2O solution and grown under controlled glasshouse conditions for a period of 20 days. Fresh leaf, stem and root samples were analysed in vivo by micro x-ray absorption spectroscopy (XAS) at the Ni-K edge.Both x-ray absorption near edge structure and extended x-ray absorption fine structure spectra were analysed, and theresulting spectra were compared with spectra obtained from nine biologically impo… more
Date: October 8, 2007
Creator: Ionescu, Mihail; Bhatia, Naveen P.; Cohen , David D.; Siegele, R.; Marcus, Matthew A.; Fakra, Sirine C. et al.
Partner: UNT Libraries Government Documents Department
open access

Study of Dark Matter inspired cMSSM scenarios at a TeV-class Linear Collider

Description: The accuracy in the measurement of the masses of sleptons and heavy Higgs bosons in cMSSM scenarios, compatible with the WMAP result on cold dark matter, has been re-analysed in view of the requirements for predicting this density to a few percent level from SUSY measurements at the linear collider.
Date: October 8, 2004
Creator: Battaglia, Marco
Partner: UNT Libraries Government Documents Department
open access

CRYSTALLIZATION IN MULTICOMPONENT GLASSES

Description: In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may sett… more
Date: October 8, 2009
Creator: AA, KRUGER & PR, HRMA
Partner: UNT Libraries Government Documents Department
open access

E-Cloud Effects on Singe-Bunch Dynamics in the Proposed PS2

Description: One of the options considered for future upgrades of the LHC injector complex entails the replacement of the PSwith the PS2, a longer circumference and higher energy synchrotron. Electron cloud effects represent an importantpotential limitation to the achievement of the upgrade goals. We report the results of numerical studies aimingat estimating the e-cloud density thresholds for the occurrence of single bunch instabilities.
Date: October 8, 2010
Creator: Venturini, M.; Furman, M. & Vay, J. L.
Partner: UNT Libraries Government Documents Department
open access

IN-SITU MONITORING OF CORROSION DURING A LABORATORY SIMULATION OF OXALIC ACID CHEMICAL CLEANING

Description: The Savannah River Site (SRS) will disperse or dissolve precipitated metal oxides as part of radioactive waste tank closure operations. Previously SRS used oxalic acid to accomplish this task. To better understand the conditions of oxalic acid cleaning of the carbon steel waste tanks, laboratory simulations of the process were conducted to determine the corrosion rate of carbon steel and the generation of gases such as hydrogen and carbon dioxide. Open circuit potential measurements, linear pol… more
Date: October 8, 2007
Creator: Wiersma, B; John Mickalonis, J; Michael Poirier, M; John Pareizs, J; David Herman, D; David Beam, D et al.
Partner: UNT Libraries Government Documents Department
open access

Pitfalls of elastomer compatibility testing

Description: An extensive compatibility test program was conducted starting with 34 compounds and six 190 C fluids. Both immersion tests and simulation tests were conducted for time periods ranging from 46 hours to over six months. Deficiencies in both types of tests were determined. Immersion tests, while useful for reducing the number of candidate compounds, can easily lead to incorrect conclusions. it is essential that simulation tests be conducted before a final elastomer is selected for use in a critic… more
Date: October 8, 1982
Creator: Friese, Gilbert J.
Partner: UNT Libraries Government Documents Department
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