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Time-Reversal Analysis for Scatterer Characterization (open access)

Time-Reversal Analysis for Scatterer Characterization

Only the simplest monopole scattering behavior has usually been treated in previous time-reversal analyses. A new application of time-reversal processing of wave scattering data permits characterization of scatterers by analyzing the number and nature of the singular functions (or eigenfunctions) associated with individual scatterers when they have multiple contributions from monopole, dipole and/or quadrupole scattering terms. We discuss acoustic, elastic, and electromagnetic scattering problems for low frequencies (ka < 1, k being the wavenumber and a the radius of the scatterer). Specific examples for electromagnetic scattering from one of a number of small conducting spheres show that each sphere can have up to six distinct time-reversal eigenfunctions associated with it.
Date: November 5, 2003
Creator: Chambers, D H & Berryman, J G
Object Type: Article
System: The UNT Digital Library
A New Lifshitz Transition and the Equation of State of Osmium (open access)

A New Lifshitz Transition and the Equation of State of Osmium

We have measured the equation of state (EoS) of osmium to 75 GPa under hydrostatic conditions at room temperature using angle dispersive x-ray diffraction. A least-squares fit of the data using a third order Birch-Murnaghan EoS yields K{sub 0} = 411 {+-} 6 GPa and K'{sub 0} = 4.0 {+-} 0.2, showing osmium is in fact more compressible than diamond. Most importantly, we have documented an anomaly in the compressibility at 20.3 GPa associated with a large discontinuity in the first pressure derivative of the c/a ratio. This discontinuity likely arises from the collapse of the small hole-ellipsoid in the Fermi surface near the L point. There has been much interest in the possibility of a Lifshitz [1] or electronic topological transition (ETT) in zinc at high-pressure near 10 GPa. Interestingly, while the experimental data remain somewhat ambiguous [2-5], most simulations suggest the ETT exists in this pressure range [6-8]. Recently, Steinle-Neumann et al. [8] have shown that the transition arises from changes in the band structure near the high-symmetry point K where three bands cross the Fermi surface upon compression. Thus one might expect that other hcp metals should exhibit similar phenomena. The hcp 4d and 5d transition elements …
Date: November 5, 2003
Creator: Occelli, F.; Aracne, C. M.; Teter, D. M.; Hanfland, M.; Canny, B.; Couzinet, B. et al.
Object Type: Article
System: The UNT Digital Library
Recommendations for SZ/TSPA Model Uncertainty Analysis Concerning the Yucca Mountain Project (open access)

Recommendations for SZ/TSPA Model Uncertainty Analysis Concerning the Yucca Mountain Project

This report considers the problem of how best to evaluate the stability (i.e., sampling reliability) of Monte Carlo outputs obtained for two Yucca Mountain Project (YMP) modeling components, namely, outputs for the Saturated Zone (SZ) model, and for the Total System Performance Assessment (TSPA) model. One approach considered is the one that has been employed to date, namely, the application of Monte Carlo methods. Also considered in this context are potential improvements that might be obtained by the additional use of a Monte Carlo ''quitting rule'', such as that defined by Woo (1991), to select the number of Monte Carlo sample runs to perform. By the Monte Carlo approach, each output-value sample (realization) is calculated as a function of a sample-value vector of stochastic realizations, each of which in turn corresponds to a value of a corresponding distributed input variable. Abstractions from the SZ model and the Biosphere model are both used as input to the TSPA model. Sets of stochastic realizations required for SZ and TSPA abstractions ''expensive'' to generate, so the practical issue addressed by a ''quitting rule'' is how to determine what number of realizations is ''enough'' for the purpose of characterizing sampling error in the Monte …
Date: November 5, 2003
Creator: Bogen, K T
Object Type: Report
System: The UNT Digital Library
Surface Sensitivity of Fast Superconducting Ion Detectors for Time-of-Flight Mass Spectrometry (open access)

Surface Sensitivity of Fast Superconducting Ion Detectors for Time-of-Flight Mass Spectrometry

We are developing the spatial uniformity of superconducting tunnel junction detectors with a size of 200 {micro}m is improved by increasing the Al thickness of the Nb/Al proximitized electrodes in an energy range of 5-10 keV, which is in the same order as an acceleration energy in time-of-flight mass spectroscopy (TOF-MS). It has been confirmed in TOF experiments with Ta ions and Ta clusters that the proximitized junction detectors clearly separate different ionic states and multi-hit events in impact energy spectra, and moreover can reveal a difference in ion species or ion-surface collision dynamics. However, a better spatial uniformity is not always good for TOF-MS, because a detector with the thicker Al layers has a lower superconducting energy gap, which results in improper detector operation because of a temperature rise due to heat radiation.
Date: November 5, 2004
Creator: Ohkubo, M; Ukibe, M; Saito, N; Kushino, A; Ichimura, S & Friedrich, S
Object Type: Article
System: The UNT Digital Library
Raman spectroscopy under extreme conditions (open access)

Raman spectroscopy under extreme conditions

We report the results of Raman measurements of various materials under simultaneous conditions of high temperature and high pressure in the diamond anvil cell (DAC). High temperatures are generated by laser heating or internal resistive (ohmic) heating or a combination of both. We present Raman spectra of cubic boron nitride (cBN) to 40 GPa and up to 2300 K that show a continuous pressure and temperature shift of the frequency of the transverse optical mode. We have also obtained high-pressure Raman spectra from a new noble metal nitride, which we synthesized at approximately 50 GPa and 2000 K. We have obtained high-temperature spectra from pure nitrogen to 39 GPa and up to 2000 K, which show the presence of a hot band that has previously been observed in CARS measurements. These measurements have also allowed us to constrain the melting curve and to examine changes in the intramolecular potential with pressure.
Date: November 5, 2004
Creator: Goncharov, A F & Crowhurst, J C
Object Type: Article
System: The UNT Digital Library
CSEWG SYMPOSIUM, A CSWEG RETROSPECTIVE. 35TH ANNIVERSARY CROSS SECTION EVALUATION WORKING GROUP, NOV. 5, 2001, BROOKHAVEN NATIONAL LABORATORY. (open access)

CSEWG SYMPOSIUM, A CSWEG RETROSPECTIVE. 35TH ANNIVERSARY CROSS SECTION EVALUATION WORKING GROUP, NOV. 5, 2001, BROOKHAVEN NATIONAL LABORATORY.

None
Date: November 5, 2001
Creator: Dunford, C.; Holden, N. & Pearlstein, S.
Object Type: Report
System: The UNT Digital Library
The Llano News (Llano, Tex.), Vol. 122, No. 6, Ed. 1 Wednesday, November 5, 2008 (open access)

The Llano News (Llano, Tex.), Vol. 122, No. 6, Ed. 1 Wednesday, November 5, 2008

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2008
Creator: Moreno, Eric L.
Object Type: Newspaper
System: The Portal to Texas History
[Letter from the Board of Directors Nominations Committee to the Publisher-Representatives of Member Papers on November, 5, 2007] (open access)

[Letter from the Board of Directors Nominations Committee to the Publisher-Representatives of Member Papers on November, 5, 2007]

Letter from the Board of Directors Nominations Committee to the Publisher-Representatives of Member Papers on November, 5, 2007. The letter is in regards to the nominations committee submitting the following nominations for places on the association's Board of Directors for the Texas Daily Newspapers Association.
Date: November 5, 2007
Creator: Board of Directors
Object Type: Letter
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 20, Ed. 1 Tuesday, November 5, 2002 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 88, No. 20, Ed. 1 Tuesday, November 5, 2002

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2002
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 45, Ed. 1 Monday, November 5, 2001 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 45, Ed. 1 Monday, November 5, 2001

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2001
Creator: Quinnelly, Lorrie J.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 46, Ed. 1 Wednesday, November 5, 2003 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 46, Ed. 1 Wednesday, November 5, 2003

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2003
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 46, Ed. 1 Friday, November 5, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 46, Ed. 1 Friday, November 5, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 361, Ed. 1 Sunday, November 5, 2006 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 361, Ed. 1 Sunday, November 5, 2006

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2006
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 94, No. 46, Ed. 1 Wednesday, November 5, 2008 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 94, No. 46, Ed. 1 Wednesday, November 5, 2008

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2008
Creator: Shance, Brenda
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 38, Ed. 1 Thursday, November 5, 2009 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 38, Ed. 1 Thursday, November 5, 2009

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2009
Creator: Shance, Brenda
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 308, Ed. 1 Monday, November 5, 2007 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 92, No. 308, Ed. 1 Monday, November 5, 2007

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: November 5, 2007
Creator: Mattox, Jami
Object Type: Newspaper
System: The Gateway to Oklahoma History
Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 22, No. 63, Ed. 1 Sunday, November 5, 2000 (open access)

Levelland and Hockley County News-Press (Levelland, Tex.), Vol. 22, No. 63, Ed. 1 Sunday, November 5, 2000

Semiweekly newspaper from Levelland, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2000
Creator: Rigg, John
Object Type: Newspaper
System: The Portal to Texas History
Yoakum Herald-Times (Yoakum, Tex.), Vol. 111, No. 45, Ed. 1 Wednesday, November 5, 2003 (open access)

Yoakum Herald-Times (Yoakum, Tex.), Vol. 111, No. 45, Ed. 1 Wednesday, November 5, 2003

Weekly newspaper from Yoakum, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2003
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 344, Ed. 1 Tuesday, November 5, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 344, Ed. 1 Tuesday, November 5, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 340, Ed. 1 Wednesday, November 5, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 340, Ed. 1 Wednesday, November 5, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 83, No. 337, Ed. 1 Friday, November 5, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 83, No. 337, Ed. 1 Friday, November 5, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 49, No. 62, Ed. 1 Friday, November 5, 2004 (open access)

Hudspeth County Herald and Dell Valley Review (Dell City, Tex.), Vol. 49, No. 62, Ed. 1 Friday, November 5, 2004

Weekly newspaper from Dell City, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2004
Creator: Lynch, Mary Louise
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 331, Ed. 1 Saturday, November 5, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 331, Ed. 1 Saturday, November 5, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 340, Ed. 1 Monday, November 5, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 340, Ed. 1 Monday, November 5, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: November 5, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History