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[A-1 Office Supply]

Photograph of the R. F. Scott building, which houses the A-1 Office Supply store, on the Fountain Square in Paris, Texas.
Date: November 13, 2008
Creator: Bell, Jim
Object Type: Photograph
System: The Portal to Texas History

[A-1 Office Supply]

Photograph of the exterior of the A-1 Office Supply store on Lamar Avenue in Paris, Texas. The Grand Theater and other buildings are visible in the background.
Date: November 13, 2008
Creator: Bell, Jim
Object Type: Photograph
System: The Portal to Texas History
(2,2-Bipyridyl)bis(eta5-1,2,3,4,5-pentamethylcyclopentadienyl)Strontium(II) (open access)

(2,2-Bipyridyl)bis(eta5-1,2,3,4,5-pentamethylcyclopentadienyl)Strontium(II)

In the title compound, the Sr-N distances are 2.624 (3) and 2.676 (3) Angstroms. The Sr-centroid distances are 2.571 and 2.561 Angstroms. The N-C-C-N torsion angle in the bipyridine ligand is 2.2 (4){sup o}. Interestingly, the bipyridine ligand is tilted. The angle between the plane defined by Sr1, N1 and N2 and the plane defined by the 12 atoms of the bipyridine ligand is 10.7{sup o}.
Date: July 3, 2008
Creator: Kazhdan, Daniel; Kazhdan, Daniel; Hu, Yung-Jin; Kokai, Akos; Levi, Zerubba & Rozenel, Sergio
Object Type: Article
System: The UNT Digital Library
3,2-HOPO Complexes of Near-Infra-Red (NIR) Emitting Lanthanides: Sensitization of Ho(III) and Pr(III) in Aqueous Solution (open access)

3,2-HOPO Complexes of Near-Infra-Red (NIR) Emitting Lanthanides: Sensitization of Ho(III) and Pr(III) in Aqueous Solution

There is a growing interest in Near Infra-Red (NIR) emission originating from organic complexes of Ln{sup III} cations. As a major impetus, biological tissues are considerably more transparent at these low energy wavelengths when compared to visible radiation, which facilitates deeper penetration of incident and emitted light. Furthermore, the long luminescence lifetimes of Ln{sup III} complexes (eg. Yb{sup III}, {tau}{sub rad} {approx} 1 ms) when compared to typical organic molecules can be utilized to vastly improve signal to noise ratios by employing time-gating techniques. While the improved quantum yield of Yb{sub III} complexes when compared to other NIR emitters favors their use for bioimaging applications, there has also been significant interest in the sensitized emission from other 4f metals such as Ln = Nd, Ho, Pr and Er which have well recognized applications as solid state laser materials (eg. Nd {approx} 1.06 {micro}m, Ho {approx} 2.09 {micro}m), and in telecommunications (eg. Er {approx} 1.54 {micro}m) where they can be used for amplification of optical signals. As a result of their weak (Laporte forbidden) f-f absorptions, the direct excitation of Ln{sup III} cations is inefficient, and sensitization of the metal emission is more effectively achieved using the so-called antenna effect. We …
Date: May 19, 2008
Creator: Moore, Evan G.; Szigethy, Geza; Xu, Jide; Palsson, Lars-Olof; Beeby, Andrew & Raymond, Kenneth N.
Object Type: Article
System: The UNT Digital Library
3-D Micro-Scale Machining Implementation (open access)

3-D Micro-Scale Machining Implementation

The KCP investigated milling, turning, and wire EDMing features at a micro-scale using existing equipment to find the limitations and hindrances to producing future designs.
Date: October 20, 2008
Creator: Boucher, Christopher L.
Object Type: Report
System: The UNT Digital Library
3-D Microprobe Metrology (open access)

3-D Microprobe Metrology

This report documents the results of a project undertaken to develop an ultra-high-accuracy measurement capability, which is necessary to address a rising trend toward miniaturized mechanical products exhibiting dramatically reduced product tolerances. A significant improvement in measurement capability is therefore required to insure that a 4:1 ratio can be maintained between product tolerances and measurement uncertainty.
Date: October 14, 2008
Creator: Swallow, Kevin
Object Type: Report
System: The UNT Digital Library
3-D Model of Broadband Emission from Supernova Remnants Undergoing Non-linear Diffusive Shock Acceleration (open access)

3-D Model of Broadband Emission from Supernova Remnants Undergoing Non-linear Diffusive Shock Acceleration

We present a 3-dimensional model of supernova remnants (SNRs) where the hydrodynamical evolution of the remnant is modeled consistently with nonlinear diffusive shock acceleration occurring at the outer blast wave. The model includes particle escape and diffusion outside of the forward shock, and particle interactions with arbitrary distributions of external ambient material, such as molecular clouds. We include synchrotron emission and cooling, bremsstrahlung radiation, neutral pion production, inverse-Compton (IC), and Coulomb energy-loss. Boardband spectra have been calculated for typical parameters including dense regions of gas external to a 1000 year old SNR. In this paper, we describe the details of our model but do not attempt a detailed fit to any specific remnant. We also do not include magnetic field amplification (MFA), even though this effect may be important in some young remnants. In this first presentation of the model we don't attempt a detailed fit to any specific remnant. Our aim is to develop a flexible platform, which can be generalized to include effects such as MFA, and which can be easily adapted to various SNR environments, including Type Ia SNRs, which explode in a constant density medium, and Type II SNRs, which explode in a pre-supernova wind. When …
Date: July 2, 2008
Creator: Lee, Shiu-Hang; Kamae, Tuneyoshi & Ellison, Donald C.
Object Type: Article
System: The UNT Digital Library
A 3-D model of superfluid helium suitable for numerical analysis (open access)

A 3-D model of superfluid helium suitable for numerical analysis

The two-fluid description is a very successful phenomenological representation of the properties of Helium II. A 3-D model suitable for numerical analysis based on the Landau-Khalatnikov description of Helium II is proposed. In this paper we introduce a system of partial differential equations that is both complete and consistent as well as practical, to be used for a 3-D solution of the flow of Helium II. The development of a 3-D numerical model for Helium II is motivated by the need to validate experimental results obtained by observing the normal component velocity distribution in a Helium II thermal counter-flow using the Particle Image Velocimetry (PIV) technique.
Date: January 1, 2008
Creator: Darve, C.; U., /Fermilab /Northwestern; Patankar, N.A.; U., /Northwestern; Van Sciver, S.W. & Lab., /Natl. High Mag. Field
Object Type: Article
System: The UNT Digital Library
[5 Days Left To Enter TDNA Awards Contest] (open access)

[5 Days Left To Enter TDNA Awards Contest]

A notice from the Texas Daily Newspaper Associations, which states that the deadline to enter the TDNA Awards is in five days, a January 15 deadline. The document requests that TDNA members pass the notice along to publishers, editors, copy editors, sportswriters, marketing and promotion staff who have worked hard to promote their newspapers to the community that the deadline is soon. The document also details the type of awards that are available. Winners will receive awards at the 2006 TDNA Annual Meeting on Monday, March 20, 2006 at the Renaissance Worthington Hotel in Fort Worth.
Date: January 10, 2008
Creator: Texas Daily Newspaper Association
Object Type: Text
System: The UNT Digital Library
12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments (open access)

12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments

A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e. mean ionization state 13-16), based on the observed ratio of K{alpha} to K{beta}. Kr gas jets provide a debris-free high energy K{alpha} source for time-resolved diagnosis of dense matter.
Date: April 22, 2008
Creator: Kugland, N.; Constantin, C. G.; Niemann, C.; Neumayer, P.; Chung, H.; Doppner, T. et al.
Object Type: Article
System: The UNT Digital Library
14-MeV Neutron Generator Used as a Thermal Neutron Source (open access)

14-MeV Neutron Generator Used as a Thermal Neutron Source

One of the most important applications of the general purpose Monte Carlo N-Particle (MCNPS and MCNPX) codes is neutron shielding design. We employed this method to simulate the shield of a 14-MeV neutron generator used as a thermal neutron source providing an external thermal neutron beam for testing large area neutron detectors developed for diffraction studies in biology and also useful for national security applications. Nuclear reactors have been the main sources of neutrons used for scientific applications. In the past decade, however, a large number of reactors have been shut down, and the importance of other, smaller devices capable of providing neutrons for research has increased. At Brookhaven National Laboratory a moderated Am-Be neutron source with shielding is used for neutron detector testing. This source is relatively weak, but provides a constant flux of neutrons, even when not in use. The use of a 14 MeV energized neutron generator, with an order of magnitude higher neutron flux has been considered to replace the Am-Be source, but the higher fast neutron yield requires a more careful design of moderator and shielding. In the present paper we describe a proposed shielding configuration based on Monte Carlo calculations, and provide calculated neutron …
Date: August 10, 2008
Creator: Dioszegi, I.
Object Type: Article
System: The UNT Digital Library
A 15-T Pulsed Solenoid for a High-Power Target Experiment (open access)

A 15-T Pulsed Solenoid for a High-Power Target Experiment

The MERIT experiment, which ran at CERN in 2007, is a proof-of-principle test for a target system that converts a 4-MW proton beam into a high-intensity muon beam for either a neutrino factory complex or a muon collider. The target system is based on a free mercury jet that intercepts an intense proton beam inside a 15-T solenoidal magnetic field. Here, we describe the design and performance of the 15-T, liquid-nitrogen-precooled, copper solenoid magnet.
Date: June 23, 2008
Creator: Kirk, H. G.; Efthymiopoulos, I.; Fabich, A.; Haug, F.; Pereira, H.; Titus, P. et al.
Object Type: Article
System: The UNT Digital Library
20% Wind Energy by 2030 (open access)

20% Wind Energy by 2030

This analysis explores one clearly defined scenario for providing 20% of our nations electricity demand with wind energy by 2030 and contrasts it to a scenario of no new wind power capacity.
Date: July 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
20% Wind Energy by 2030: Increasing Wind Energy's Contribution to U.S. Electricity Supply; Executive Summary (Revised) (open access)

20% Wind Energy by 2030: Increasing Wind Energy's Contribution to U.S. Electricity Supply; Executive Summary (Revised)

This document is a 21-page summary of the 200+ page analysis that explores one clearly defined scenario for providing 20% of our nation's electricity demand with wind energy by 2030 and contrasts it to a scenario of no new U.S. wind power capacity.
Date: December 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
20% Wind Energy - Diversifying Our Energy Portfolio and Addressing Climate Change (Brochure) (open access)

20% Wind Energy - Diversifying Our Energy Portfolio and Addressing Climate Change (Brochure)

This brochure describes the R&D efforts needed for wind energy to meet 20% of the U.S. electrical demand by 2030. In May 2008, DOE published its report, 20% Wind Energy by 2030, which presents an in-depth analysis of the potential for wind energy in the United States and outlines a potential scenario to boost wind electric generation from its current production of 16.8 gigawatts (GW) to 304 GW by 2030. According to the report, achieving 20% wind energy by 2030 could help address climate change by reducing electric sector carbon dioxide (CO2) emissions by 825 million metric tons (20% of the electric utility sector CO2 emissions if no new wind is installed by 2030), and it will enhance our nation's energy security by diversifying our electricity portfolio as wind energy is an indigenous energy source with stable prices not subject to fuel volatility. According to the report, increasing our nation's wind generation could also boost local rural economies and contribute to significant growth in manufacturing and the industry supply chain. Rural economies will benefit from a substantial increase in land use payments, tax benefits and the number of well-paying jobs created by the wind energy manufacturing, construction, and maintenance industries. …
Date: May 1, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
[24-Hour Film Feast with Malik Yoba] captions transcript

[24-Hour Film Feast with Malik Yoba]

Video footage from The Black Academy of Arts and Letters recorded during TBAALs 2008 24-Hour Filmfeast featuring actor Malik Yoba on March 1st. The footage features a live Q&A discussion with Yoba on his career and perspective on the industry.
Date: March 1, 2008
Creator: Yoba, Malik
Object Type: Video
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0001]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0002]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0003]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0004]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0005]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0006]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0007]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library

[24-Hour FilmFeast Photograph UNTA_AR0797-138-004-0008]

Photograph taken at a 24-Hour FilmFeast event featuring Malik Yoba, sponsored by The Black Academy of Arts and Letters in Dallas, Texas.
Date: March 1, 2008
Creator: Smith, David L., III
Object Type: Photograph
System: The UNT Digital Library