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''Atomic Optics'': Nonimaging Optics on the Nanoscale (open access)

''Atomic Optics'': Nonimaging Optics on the Nanoscale

This is the final report for a one year close out extension of our basic research program that was established at the University of Chicago more than sixteen years ago to explore and develop the optical sub-discipline that has come to be known as ''nonimaging optics''. This program has been extremely fruitful, having both broadened the range of formalism available for workers in this field and led to the discovery of many new families of optical devices. These devices and techniques have applications wherever the efficient transport and transformation of light distributions are important, in particular in illumination, fiber optics, collection and concentration of sunlight, and the detection of faint light signals in physics and astrophysics. Over the past thirty years, Nonimaging Optics (Welford and Winston, 1989) has brought a fresh approach to the analysis of many problems in classical macro-scale optics. Through the application of phase-space concepts, statistical methods, thermodynamic arguments, etc., many previously established performance limits were able to be broken and many technical surprises with exciting practical applications were discovered. The most recent three-year phase of our long-term continuing program ended in late 2002 and emphasized extending our work in geometrical optics and expanding it to include …
Date: January 15, 2005
Creator: O'Gallagher, Roland Winston Joseph
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 42, Ed. 1 Saturday, January 15, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 42, Ed. 1 Saturday, January 15, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: January 15, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
CH-TRU Waste Content Codes (CH-TRUCON) (open access)

CH-TRU Waste Content Codes (CH-TRUCON)

The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container. Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 …
Date: January 15, 2005
Creator: Westinghouse TRU Solutions LLC
Object Type: Report
System: The UNT Digital Library

[CMP staff member in production control room, 1]

Photograph of a member of the Center for Media Production (CMP) staff in a production control room on the UNT campus. The man can be seen on the left side of the photograph, facing to the right of the camera. A television on the wall in front of him is displaying footage of an individual's feet in athletic shoes.
Date: January 15, 2005
Creator: University of North Texas. Center for Media Production.
Object Type: Photograph
System: The UNT Digital Library

[CMP staff member in production control room, 2]

Photograph of a member of the Center for Media Production (CMP) staff in a production control room on the UNT campus. The man can be seen on the left side of the photograph, facing to the right of the camera. A television on the wall in front of him is displaying footage of an individual standing next to a stop sign. The same footage can be seen on a second television on the left.
Date: January 15, 2005
Creator: University of North Texas. Center for Media Production.
Object Type: Photograph
System: The UNT Digital Library
Cyclotron Resonance and Quasiparticles (open access)

Cyclotron Resonance and Quasiparticles

This introductory paper contains personal perspectives about the importance of cyclotron resonance in forming our modern view of solids. The papers following this one will discuss the discovery, refinements, and some of the latest developments. Although I will touch on some of these subjects, I leave the details to the other authors and in the main focus on the conceptual impact of the work. I propose that it was experiments based on cyclotron resonance which established the quasiparticle concept.
Date: January 15, 2005
Creator: Cohen, Marvin L.
Object Type: Article
System: The UNT Digital Library
Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report (open access)

Evaluation of Roof Bolting Requirements Based on In-Mine Bolter Drilling Progress Report

In this quarter, the field, theoretical and programming works have been performed toward achieving the research goals set in the proposal. The main accomplishments in this quarter included: (1) one more field test has been conducted in an underground coal mine, (2) optimization studies of the control parameters have been conducted, (3) method to use torque to thrust ratio as indicator of rock relative hardness has also been explored, and (4) about 98% of the development work for the roof geology mapping program, MRGIS, has completed, (5) A real time roof geology mapping system for roof bolters in limestone mine, including a special version of the geology mapping program and hardware, has already been verified to perform very well in underground production condition.
Date: January 15, 2005
Creator: Peng, Syd S.
Object Type: Report
System: The UNT Digital Library
[Funeral Program for Jessie Alexander, III, January 15, 2005] (open access)

[Funeral Program for Jessie Alexander, III, January 15, 2005]

Funeral program for Jessie "Dutch" Alexander III, born August 31, 1945 and died January 8, 2005. The funeral was held January 15, 2005 at Calvary Baptist Church.
Date: January 15, 2005
Creator: unknown
Object Type: Pamphlet
System: The Portal to Texas History
Further results about field theory on the world sheet and stringformation (open access)

Further results about field theory on the world sheet and stringformation

The present article is the continuation of the earlier work, which used the world sheet representation and the mean field approximation to sum planar graphs in massless {phi}{sup 3} field theory. The authors improve on the previous work in two respects: A prefactor in the world sheet propagator that had been neglected is now taken into account. In addition, they introduce a non-zero bare mass for the field {phi}. Working with a theory with cutoff and using the mean field approximation, they find that, depending on the range of values of the mass and coupling constant, the model has two phases: A string forming phase and a perturbative field theory phase. They also find the generation of a new degree of freedom, which was not in the model originally. This new degree of freedom can be thought of as the string slope, which is now promoted into a fluctuating dynamical variable. Finally, they show that the introduction of the bare mass makes it possible to renormalize the model.
Date: January 15, 2005
Creator: Bardakci, Korbut
Object Type: Article
System: The UNT Digital Library
The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 23, No. 2, Ed. 1 Saturday, January 15, 2005 (open access)

The Gayly Oklahoman (Oklahoma City, Okla.), Vol. 23, No. 2, Ed. 1 Saturday, January 15, 2005

Semi-monthly newspaper from Oklahoma City, Oklahoma that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: January 15, 2005
Creator: Hawkins, Don
Object Type: Newspaper
System: The UNT Digital Library
Halliburton Composite Bridge Plug Assembly (open access)

Halliburton Composite Bridge Plug Assembly

The overall objectives of this CRADA were to assist Halliburton in analyzing a composite bridge plug and to determine why their original design was failing in the field. In Phase 1, finite element analyses were done on the original composite slip design and several alternative designs. The composite slip was the component in the bridge plug that was failing. The finite element code ABAQUS was used for these calculations and I-DEAS was used as the pre- and post-processor in the analyses. Several different designs and materials were analyzed and recommendations were made towards improving the design. In Phase 2, the objective was to develop finite element models that would accurately represent the deformations in the entire all-composite 4-1/2' diameter bridge plug assembly. The finite element code LS-DYNA was used and the results from this effort were intended to expand Halliburton's composite design and analysis capabilities with regard to developing future composite components for downhole tools. In addition to the finite element modeling, this effort involved the utilization of micromechanics to determine the necessary composite material properties that were needed as input for finite element codes.
Date: January 15, 2005
Creator: Starbuck, J. M.; Luttrell, C. R. & Aramayo, G.
Object Type: Report
System: The UNT Digital Library
Hydrogen and Nitrogen Control in Ladle and Casting Operations (open access)

Hydrogen and Nitrogen Control in Ladle and Casting Operations

In recent years there has been an increasing demand to reduce and control the amount of dissolved gases in steel. Hydrogen and nitrogen are two of the most important gases which when dissolved in liquid steel affect its properties significantly. Several steelmaking additions have been investigated in this research for their effect on the hydrogen and nitrogen content of steels. It has been established that calcium hydroxide (hydrated lime) acts as a source of hydrogen. Carburizers, such as metallurgical coke, were found to result in no hydrogen pickup when added to liquid steel. Addition of petroleum coke, on the other hand, increased the hydrogen content of liquid steel. Ferroalloy such as medium carbon ferromanganese when added to the liquid iron was found to increase its nitrogen content, the increase being proportional to the amount of ferroalloy added. Similarly, addition of pitch coke, which had a significant nitrogen impurity, increased the nitrogen content of liquid iron. A mathematical model was developed to quantify the absorption of nitrogen and hydrogen from the air bubbles entrained during tapping of liquid steel. During the bottom stirring of liquid metal in a ladle, the inert gas escaping from the top displaces the slag layer and …
Date: January 15, 2005
Creator: Fruehan, Richard J. & Misra, Siddhartha
Object Type: Report
System: The UNT Digital Library
Neutron Capture Experiments on Unstable Nuclei (open access)

Neutron Capture Experiments on Unstable Nuclei

The overall objective of this project is the measurement of neutron capture cross sections of importance to stewardship science and astrophysical modeling of nucleosynthesis, while at the same time helping to train the next generation of scientists with expertise relevant to U.S. national nuclear security missions and to stewardship science. A primary objective of this project is to study neutron capture cross sections for various stable and unstable isotopes that will contribute to the Science Based Stockpile Stewardship (SBSS) program by providing improved data for modeling and interpretation of nuclear device performance. Much of the information obtained will also be important in astrophysical modeling of nucleosynthesis. Measurements of these neutron capture cross sections are being conducted in collaboration with researchers at the Los Alamos Neutron Science Center (LANSCE) facility using the unique Detector for Advanced Neutron Capture Experiments (DANCE). In our early discussions with the DANCE group, decisions were made on the first cross sections to be measured and how our expertise in target preparation, radiochemical separations chemistry, and data analysis could best be applied. The initial emphasis of the project was on preparing suitable targets of both natural and separated stable europium isotopes in preparation for the ultimate goal …
Date: January 15, 2005
Creator: Schwantes, Jon M.; Sudowe, Ralf; Folden, Charles M., III; Nitsche, Heino & Hoffman, Darleane C.
Object Type: Report
System: The UNT Digital Library
Oral History Interview with Larry Aldrich, December 2, 2003 (open access)

Oral History Interview with Larry Aldrich, December 2, 2003

Interview with Larry Aldrich, a U.S. Air Force veteran who served in England during the Iraqi war. Aldrich describes his experiences when he enlisted including his training and work as a guard at a nuclear weapons storage facility and later, overseas at RAF Lakenheath.
Date: January 15, 2005
Creator: Thibodaux, Dana & Aldrich, Larry
Object Type: Text
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 112, No. 10, Ed. 1 Saturday, January 15, 2005 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 112, No. 10, Ed. 1 Saturday, January 15, 2005

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: January 15, 2005
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
Report on Texas Bridges as of September 2004 (open access)

Report on Texas Bridges as of September 2004

This report describes bridges and their conditions in Texas. The report provides information on the types of bridges, integrity of them, and prioritizes their need for upgrade.
Date: January 15, 2005
Creator: Texas. Department of Transportation.
Object Type: Report
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 106, No. 267, Ed. 1 Tuesday, February 15, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 267, Ed. 1 Tuesday, February 15, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 15, 2005
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Atomic-Resolution 3D Electron Microscopy with Dynamic Diffraction (open access)

Atomic-Resolution 3D Electron Microscopy with Dynamic Diffraction

Achievement of atomic-resolution electron-beam tomography will allow determination of the three-dimensional structure of nanoparticles (and other suitable specimens) at atomic resolution. Three-dimensional reconstructions will yield ''section'' images that resolve atoms overlapped in normal electron microscope images (projections), resolving lighter atoms such as oxygen in the presence of heavier atoms, and atoms that lie on non-lattice sites such as those in non-periodic defect structures. Lower-resolution electron microscope tomography has been used to produce reconstructed 3D images of nanoparticles [1] but extension to atomic resolution is considered not to be straightforward. Accurate three-dimensional reconstruction from two-dimensional projections generally requires that intensity in the series of 2-D images be a monotonic function of the specimen structure (often specimen density, but in our case atomic potential). This condition is not satisfied in electron microscopy when specimens with strong periodicity are tilted close to zone-axis orientation and produce ''anomalous'' image contrast because of strong dynamic diffraction components. Atomic-resolution reconstructions from tilt series containing zone-axis images (with their contrast enhanced by strong dynamical scattering) can be distorted when the stronger zone-axis images overwhelm images obtained in other ''random'' orientations in which atoms do not line up in neat columns. The first demonstrations of 3-D reconstruction to …
Date: February 15, 2005
Creator: O'Keefe, Michael A.; Downing, Kenneth H.; Wenk, Hans-Rudolf & Meisheng, Hu
Object Type: Article
System: The UNT Digital Library
Boerne Star & Hill Country Recorder (Boerne, Tex.), Vol. 99, No. 6, Ed. 1 Tuesday, February 15, 2005 (open access)

Boerne Star & Hill Country Recorder (Boerne, Tex.), Vol. 99, No. 6, Ed. 1 Tuesday, February 15, 2005

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: February 15, 2005
Creator: Watson, Steven G.
Object Type: Newspaper
System: The Portal to Texas History
The Broader Middle East and North Africa Initiative: An Overview (open access)

The Broader Middle East and North Africa Initiative: An Overview

The Broader Middle East and North Africa Initiative (BMENA) is a multilateral development and reform plan aimed at fostering economic and political liberalization in a wide geographic area of Arab and non-Arab Muslim countries. In December 2004, the first BMENA meeting took place in Rabat, Morocco and was called the “Forum for the Future.”At the forum, foreign ministers and finance ministers of the countries in the region stretching from Morocco to Pakistan as well as from the countries of the G8 pledged to create several new development programs and committed $60 million to a regional fund for business development. Critics of BMENA contend that the initiative focuses too heavily on economic issues instead of political reform and does little to strengthen non-governmental organizations and civil society groups in Arab and non- Arab Muslim countries.
Date: February 15, 2005
Creator: Sharp, Jeremy M.
Object Type: Report
System: The UNT Digital Library
Ceramic Laser Materials (open access)

Ceramic Laser Materials

Transparent ceramic materials have several major advantages over single crystals in laser applications, not the least of which is the ability to make large aperture parts in a robust manufacturing process. After more than a decade of working on making transparent YAG:Nd, Japanese workers have recently succeeded in demonstrating samples that performed as laser gain media as well as their single crystal counterparts. Since then several laser materials have been made and evaluated. For these reasons, developing ceramic laser materials is the most exciting and futuristic materials topic in today's major solid-state laser conferences. We have established a good working relationship with Konoshima Ltd., the Japanese producer of the best ceramic laser materials, and have procured and evaluated slabs designed by us for use in our high-powered SSHCL. Our measurements indicate that these materials will work in the SSHCL, and we have nearly completed retrofitting the SSHCL with four of the largest transparent ceramic YAG:Nd slabs in existence. We have also begun our own effort to make this material and have produced samples with various degrees of transparency/translucency. We are in the process of carrying out an extensive design-of-experiments to establish the significant process variables for making transparent YAG. Finally …
Date: February 15, 2005
Creator: Soules, T F; Clapsaddle, B J; Landingham, R L & Schaffers, K I
Object Type: Report
System: The UNT Digital Library
Comments on 'Pore-Scale Visulization of Colloid Transport andRetention in Partly Saturated Porous Media' (open access)

Comments on 'Pore-Scale Visulization of Colloid Transport andRetention in Partly Saturated Porous Media'

The recent study by Crist et al. (2004) attempted to provide pore scale insights into mechanisms responsible for controlling colloid transport in unsaturated porous media. However, because they relied on images obtained along surfaces that were open to the atmosphere, artificial evaporation resulted in 2 more critical artifacts; formation of air-water-solid (AWS) contact lines, and advection/deposition of colloids to AWS contact lines. These evaporation-related artifacts need to be addressed because they account for most of the colloid deposition at AWS contact lines reported in Crist et al. (2004)...As stated in Crist el al. (2004), ''... the front panel was removed to avoid light reflections that obscured the view and, thus, exposed one side of the sand column to air''. Although a more recent paper (Crist et al., 2005) also presents results using the same methods and is therefore also affected by evaporation, we will restrict our present comments to Crist et al. (2004). Here, we show that removal of the front panel results in a sequence of three critical artifacts; (1) significant evaporation, (2) drying of thin films and formation of air-water-solid (AWS) contact lines, and (3) advection of colloids to AWS contact lines where they are deposited. As explained …
Date: February 15, 2005
Creator: Wan, Jiamin & Tokunaga, Tetsu K.
Object Type: Article
System: The UNT Digital Library
Contract Management: The Air Force Should Improve How It Purchases AWACS Spare Parts (open access)

Contract Management: The Air Force Should Improve How It Purchases AWACS Spare Parts

A letter report issued by the Government Accountability Office with an abstract that begins "Over the past several years, the Air Force has negotiated and awarded more than $23 million in contracts to the Boeing Corporation for the purchase of certain spare parts for its Airborne Warning and Control System (AWACS) aircraft. Since they first became operational in March 1977, AWACS aircraft have provided U.S. and allied defense forces with the ability to detect, identify, and track airborne threats. In March 2003, GAO received allegations that the Air Force was overpaying Boeing for AWACS spare parts. This report provides the findings of GAO's review into these allegations. Specifically, GAO identified spare parts price increases and determined whether the Air Force obtained and evaluated sufficient information to ensure the prices were fair and reasonable. GAO also determined the extent to which competition was used to purchase the spare parts."
Date: February 15, 2005
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The crystal structure of Rv1347c, a putative antibiotic resistance protein from Mycobacterium tuberculosis, reveals a GCN5-related fold and suggests an alternative function in siderophore biosynthesis (open access)

The crystal structure of Rv1347c, a putative antibiotic resistance protein from Mycobacterium tuberculosis, reveals a GCN5-related fold and suggests an alternative function in siderophore biosynthesis

Mycobacterium tuberculosis, the cause of TB, is a devastating human pathogen. The emergence of multi-drug resistance in recent years has prompted a search for new drug targets and for a better understanding of mechanisms of resistance. Here we focus on the gene product of an open reading frame from M. tuberculosis, Rv1347c, which is annotated as a putative aminoglycoside N-acetyltransferase. The Rv1347c protein does not show this activity, however, and we show from its crystal structure, coupled with functional and bioinformatic data, that its most likely role is in the biosynthesis of mycobactin, the M. tuberculosis siderophore. The crystal structure of Rv1347c was determined by MAD phasing from selenomethionine-substituted protein and refined at 2.2 {angstrom} resolution (R = 0.227, R{sub free} = 0.257). The protein is monomeric, with a fold that places it in the GCN5-related N-acetyltransferase (GNAT) family of acyltransferases. Features of the structure are an acylCoA binding site that is shared with other GNAT family members, and an adjacent hydrophobic channel leading to the surface that could accommodate long-chain acyl groups. Modeling the postulated substrate, the N{sup {var_epsilon}}-hydroxylysine side chain of mycobactin, into the acceptor substrate binding groove identifies two residues at the active site, His130 and Asp168, …
Date: February 15, 2005
Creator: Card, G. L.; Peterson, N. A.; Smith, C. A.; Rupp, B.; Schick, B. M. & Baker, E. N.
Object Type: Article
System: The UNT Digital Library