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Direct Observations of Sigma Phase Formation in Duplex Stainless Steels using In Situ Synchrotron X-Ray Diffraction (open access)

Direct Observations of Sigma Phase Formation in Duplex Stainless Steels using In Situ Synchrotron X-Ray Diffraction

The formation and growth of sigma phase in 2205 duplex stainless steel was observed and measured in real time using synchrotron radiation during 10 hr isothermal heat treatments at temperatures between 700 C and 850 C. Sigma formed in near-equilibrium quantities during the isothermal holds, starting from a microstructure which contained a balanced mixture of metastable ferrite and austenite. In situ synchrotron diffraction continuously monitored the transformation, and these results were compared to those predicted by thermodynamic calculations. Differences between the calculated and measured amounts of sigma, ferrite and austenite suggest that the thermodynamic calculations underpredict the sigma dissolution temperature by approximately 50 C. The data were further analyzed using a modified Johnson-Mehl-Avrami (JMA) approach to determine kinetic parameters for sigma formation over this temperature range. The initial JMA exponent, n, at low fractions of sigma was found to be approximately 7.0, however, towards the end of the transformation, n decreased to values of approximately 0.75. The change in the JMA exponent was attributed to a change in the transformation mechanism from discontinuous precipitation with increasing nucleation rate, to growth of the existing sigma phase after nucleation site saturation occurred. Because of this change in mechanism, it was not possible …
Date: July 3, 2006
Creator: Elmer, J W; Palmer, T A & Specht, E D
Object Type: Article
System: The UNT Digital Library
HOTTER, SMALLER, DENSER, FASTER...AND NEARLY-PERFECT: WHAT IS THE MATTER AT RHIC? (open access)

HOTTER, SMALLER, DENSER, FASTER...AND NEARLY-PERFECT: WHAT IS THE MATTER AT RHIC?

The experimental and theoretical status of the ''near perfect fluid'' at RHIC is discussed. While the hydrodynamic paradigm for understanding collisions at RHIC is well established, there remain many important open questions to address in order to understand its relevance and scope. It is also a crucial issue to understand how the early equilibration is achieved, requiring insight into the active degrees of freedom at early times.
Date: July 3, 2006
Creator: Steinberg, Peter
Object Type: Article
System: The UNT Digital Library
Coast Guard Deepwater Program: Background and Issues for Congress (open access)

Coast Guard Deepwater Program: Background and Issues for Congress

This report presents the background and issues for Congress related to Coast Guard Deepwater Program or Integrated Deepwater Systems(IDS) program.
Date: July 3, 2006
Creator: O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library
[TDNA Legislative Report, July 2006] (open access)

[TDNA Legislative Report, July 2006]

A legislative report for the Texas Daily Newspaper Association board of directors meeting to be held July 13, 2006 at the Headliners Club in Austin, Texas. The purpose of the legislative report is to give the board of directors and the association's members news updates on how the Texas newspaper industry fared during the year.
Date: July 3, 2006
Creator: Texas Daily Newspaper Association
Object Type: Report
System: The UNT Digital Library
[TDNA Administrative Report, July 2006] (open access)

[TDNA Administrative Report, July 2006]

An administrative report for the Texas Daily Newspaper Association board of directors meeting July 13, 2006. The document serves as a mean to update the board of directors, as well as association members, what is happening within TDNA as well as explain future goals and accomplishes.
Date: July 3, 2006
Creator: Texas Daily Newspaper Association
Object Type: Report
System: The UNT Digital Library
Snapping Supernovae at z>1.7 (open access)

Snapping Supernovae at z>1.7

We examine the utility of very high redshift Type Ia supernovae for cosmology and systematic uncertainty control. Next generation space surveys such as the Supernova/Acceleration Probe (SNAP) will obtain thousands of supernovae at z>1.7, beyond the design redshift for which the supernovae will be exquisitely characterized. We find that any z gtrsim 2 standard candles' use for cosmological parameter estimation is quite modest and subject to pitfalls; we examine gravitational lensing, redshift calibration, and contamination effects in some detail. The very high redshift supernovae - both thermonuclear and core collapse - will provide copious interesting information on star formation, environment, and evolution. However, the new observational systematics that must be faced, as well as the limited expansion of SN-parameter space afforded, does not point to high value for 1.7<z<3 SNe Ia in controlling evolutionary systematics relative to what SNAP can already achieve at z<1.7. Synergy with observations from JWST and thirty meter class telescopes afford rich opportunities for advances throughout astrophysics.
Date: July 3, 2006
Creator: Aldering, Greg; Kim, Alex G.; Kowalski, Marek; Linder, Eric V. & Perlmutter, Saul
Object Type: Article
System: The UNT Digital Library
[TDNA 2006 Annual Meeting Report] (open access)

[TDNA 2006 Annual Meeting Report]

The 2006 Annual Meeting Report from the Texas Daily Newspaper Association's meeting held on July 13, 2006 at the Headliners Club in Austin, Texas. The document reports that while TDNA is set to make a profit of one-thousand dollars from the recent TDNA, attendance continues to fall, having only sixty-eight guests in attendance.
Date: July 3, 2006
Creator: Texas Daily Newspaper Association
Object Type: Report
System: The UNT Digital Library
FLUCTUATION AND LOW TRANSVERSE MOMENTUM CORRELATION RESULTS FROM PHENIX. (open access)

FLUCTUATION AND LOW TRANSVERSE MOMENTUM CORRELATION RESULTS FROM PHENIX.

The PHENIX Experiment at the Relativistic Heavy Ion Collider has conducted a survey of fluctuations in charged hadron multiplicity in Au+Au and Cu+Cu collisions at {radical}s{sub NN} = 22, 62, and 200 GeV. A universal power law scaling for multiplicity fluctuations expressed as {sigma}{sup 2}/{mu}{sup 2} is observed as a function of N{sub part} for all species studied that is independent of the transverse momentum range of the measurement. PHENIX has also measured transverse momentum correlation amplitudes in p+p, d+Au, and Au+Au collisions. At low transverse momentum, significant differences in the correlations between the baseline p+p and d+Au data and the Au+Au data are presented.
Date: July 3, 2006
Creator: MITCHELL,J.T.
Object Type: Article
System: The UNT Digital Library
ENTROPY PRODUCTION AT HIGH ENERGY AND mu B. (open access)

ENTROPY PRODUCTION AT HIGH ENERGY AND mu B.

The systematics of bulk entropy production in experimental data on Ai-A, p + y and e{sup +}e{sup -} interactions at high energies and large {mu}{sub B} is discussed. It is proposed that scenarios with very early thermalization, such as Landau's hydrodynamical model, capture several essential features of the experimental results. It is also pointed out that the dynamics of systems which reach the hydrodynamic regime give similar multiplicities and angular distributions as those calculated in weak-coupling approximations (e.g. pQCD) over a wide range of beam energies. Finally, it is shown that the dynamics of baryon stopping are relevant to the physics of total entropy production, explaining why A+A and e{sup +}e{sup -} multiplicities are different at low beam energies.
Date: July 3, 2006
Creator: Steinberg, Peter
Object Type: Article
System: The UNT Digital Library
Overview of Theory and Simulations in the Heavy Ion Fusion Science Virtual National Laboratory (open access)

Overview of Theory and Simulations in the Heavy Ion Fusion Science Virtual National Laboratory

The Heavy Ion Fusion Science Virtual National Laboratory (HIFS-VNL) is a collaboration of Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, and Princeton Plasma Physics Laboratory. These laboratories, in cooperation with researchers at other institutions, are carrying out a coordinated effort to apply intense ion beams as drivers for studies of the physics of matter at extreme conditions, and ultimately for inertial fusion energy. Progress on this endeavor depends upon coordinated application of experiments, theory, and simulations. This paper describes the state of the art, with an emphasis on the coordination of modeling and experiment; developments in the simulation tools, and in the methods that underly them, are also treated.
Date: July 3, 2006
Creator: Friedman, A
Object Type: Article
System: The UNT Digital Library
Development and anlysis of fast, approximate 3D Algorithms for interpretation of multi-component induction logging data (open access)

Development and anlysis of fast, approximate 3D Algorithms for interpretation of multi-component induction logging data

This report addresses the effects of electrical anisotropy on the 3D inversion of single-well induction logging data when anisotropy is not considered. Of concern are possible artifacts that may lead to an incorrect interpretation of the formation about the borehole. Comparison is made of 3D isotropic inversion on a suite of model data, with and without anisotropy, consisting of an infinite layer and layer terminated at the borehole. In both cases, the layer dip (or well deviation) is varied. Inversion of the anisotropic data result in an overestimate of the layer conductivity, and the lateral extent of the layer about the borehole.
Date: July 3, 2006
Creator: Alumbaugh, David L.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 85, No. 234, Ed. 1 Monday, July 3, 2006 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 85, No. 234, Ed. 1 Monday, July 3, 2006

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: July 3, 2006
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
War on Drugs: The National Youth Anti-Drug Media Campaign (open access)

War on Drugs: The National Youth Anti-Drug Media Campaign

This report discusses the authorization of the National Youth Anti-Drug Media Campaign, a multi-media federal program to persuade America's youth not to use drugs, which expired at the end of FY2002. H.R. 2829 (passed by the House on March 13, 2006) and S. 2560 (reported by the Senate Judiciary Committee on May 25, 2006) would reauthorize the media campaign, along with the other programs run by the Office of National Drug Control Policy (ONDCP) during FY2007.
Date: July 3, 2006
Creator: Eddy, Mark
Object Type: Report
System: The UNT Digital Library
Disaster Debris Removal After Hurricane Katrina: Status and Associated Issues (open access)

Disaster Debris Removal After Hurricane Katrina: Status and Associated Issues

This report discusses issues associated with debris removal operations after a disaster on the scale of Katrina. In particular, it discusses why debris removal was an ongoing concern months after the hurricane, as well as factors that make debris removal such a costly, complex operation.
Date: July 3, 2006
Creator: Luther, Linda
Object Type: Report
System: The UNT Digital Library
Class Action Fairness Act of 2005: Early Judicial Interpretations (open access)

Class Action Fairness Act of 2005: Early Judicial Interpretations

This report provides early Judicial interpretations of Class Action Fairness Act of 2005.
Date: July 3, 2006
Creator: Wallace, Paul Starett, Jr.
Object Type: Report
System: The UNT Digital Library
Evaluating the Current Stance of Monetary Policy Using a Taylor Rule (open access)

Evaluating the Current Stance of Monetary Policy Using a Taylor Rule

None
Date: July 3, 2006
Creator: Labonte, Marc
Object Type: Report
System: The UNT Digital Library
Aging Infrastructure: Dam Safety (open access)

Aging Infrastructure: Dam Safety

To help inform discussions on the federal role in dam safety, this report provides background information on the nation’s dam safety activities and funding mechanisms.
Date: July 3, 2006
Creator: Lane, Nic
Object Type: Report
System: The UNT Digital Library
War on Drugs: The National Youth Anti-Drug Media Campaign (open access)

War on Drugs: The National Youth Anti-Drug Media Campaign

None
Date: July 3, 2006
Creator: Eddy, Mark
Object Type: Report
System: The UNT Digital Library
Design of a Virtual Quadrant Receiver for 4-ary Pulse Position Modulation/Optical CDMA (4-ary PPM/O-CDMA) (open access)

Design of a Virtual Quadrant Receiver for 4-ary Pulse Position Modulation/Optical CDMA (4-ary PPM/O-CDMA)

We describe a receiver that performs optical code division multiple access (O-CDMA) decoding followed by pulse position modulation (PPM) symbol detection that behaves like a radar quadrant receiver. Simulations determine the impact of multi-access interference on symbol detection for up to 32 users.
Date: July 3, 2006
Creator: Mendez, A. J.; Gagliardi, R. M.; Hernandez, V. J.; Bennett, C. V. & Lennon, W. J.
Object Type: Article
System: The UNT Digital Library
First principles study of the Young's modulus of Si <001> nanowires (open access)

First principles study of the Young's modulus of Si <001> nanowires

We report the results of first-principles calculations of the Young's modulus and other mechanical properties of hydrogen-passivated Si &lt;001&gt; nanowires. The nanowires are taken to have predominantly {l_brace}100{r_brace} surfaces, with small {l_brace}110{r_brace} facets according to the Wulff shape. The Young's modulus, the equilibrium length and the constrained residual stress of a series of prismatic beams of differing sizes is found to have a size dependence that scales like the surface area to volume ratio for all but the smallest beam. The results are compared with two different models (and the results of classical atomistic calculations based on an empirical potential). We discuss the physics of the hydrogen interactions on the surface and the charge density variations within the beam that may account for the discrepancies of the models and the first principles results.
Date: July 3, 2006
Creator: Lee, B & Rudd, R E
Object Type: Article
System: The UNT Digital Library
Exploration of methods to identify polymorphisms associated with variation in DNA repair capacity phenotypes (open access)

Exploration of methods to identify polymorphisms associated with variation in DNA repair capacity phenotypes

Elucidating the relationship between polymorphic sequences and risk of common disease is a challenge. For example, although it is clear that variation in DNA repair genes is associated with familial cancer, aging and neurological disease, progress toward identifying polymorphisms associated with elevated risk of sporadic disease has been slow. This is partly due to the complexity of the genetic variation, the existence of large numbers of mostly low frequency variants and the contribution of many genes to variation in susceptibility. There has been limited development of methods to find associations between genotypes having many polymorphisms and pathway function or health outcome. We have explored several statistical methods for identifying polymorphisms associated with variation in DNA repair phenotypes. The model system used was 80 cell lines that had been resequenced to identify variation; 191 single nucleotide substitution polymorphisms (SNPs) are included, of which 172 are in 31 base excision repair pathway genes, 19 in 5 anti-oxidation genes, and DNA repair phenotypes based on single strand breaks measured by the alkaline Comet assay. Univariate analyses were of limited value in identifying SNPs associated with phenotype variation. Of the multivariable model selection methods tested: the easiest that provided reduced error of prediction of …
Date: July 3, 2006
Creator: Jones, I. M.; Thomas, C. B.; Xi, T.; Mohrenweiser, H. W. & Nelson, D. O.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 108, No. 80, Ed. 1 Monday, July 3, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 108, No. 80, Ed. 1 Monday, July 3, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: July 3, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 254, Ed. 1 Monday, July 3, 2006 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 91, No. 254, Ed. 1 Monday, July 3, 2006

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: July 3, 2006
Creator: Stone, Greg
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Individuals with Disabilities Education Act (IDEA): Supreme Court Decisions (open access)

The Individuals with Disabilities Education Act (IDEA): Supreme Court Decisions

This report discusses the Supreme Court's decisions under the Individuals with Disabilities Education Act (IDEA).
Date: July 3, 2006
Creator: Jones, Nancy Lee
Object Type: Report
System: The UNT Digital Library