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Nanostructured Materials Integrated in Microfabricated Optical Devices (open access)

Nanostructured Materials Integrated in Microfabricated Optical Devices

This project combined nanocomposite materials with microfabricated optical device structures for the development of microsensor arrays. For the nanocomposite materials we have designed, developed, and characterized self-assembling, organic/inorganic hybrid optical sensor materials that offer highly selective, sensitive, and reversible sensing capability with unique hierarchical nanoarchitecture. Lipid bilayers and micellar polydiacetylene provided selective optical response towards metal ions (Pb(II), Hg(II)), a lectin protein (Concanavalin A), temperature, and organic solvent vapor. These materials formed as composites in silica sol-gels to impart physical protection of the self-assembled structures, provide a means for thin film surface coatings, and allow facile transport of analytes. The microoptical devices were designed and prepared with two- and four-level diffraction gratings coupled with conformal gold coatings on fused silica. The structure created a number of light reflections that illuminated multiple spots along the silica surface. These points of illumination would act as the excitation light for the fluorescence response of the sensor materials. Finally, we demonstrate an integrated device using the two-level diffraction grating coupled with the polydiacetylene/silica material.
Date: December 1, 2002
Creator: SASAKI, DARRYL Y.; LAST, JULIE A.; BONDURANT, BRUCE; WAGGONER, TINA A.; BRINKER, C. JEFFREY; KEMME, SHANALYN A. et al.
Object Type: Report
System: The UNT Digital Library
A NEAR REAL-TIME BERYLLIUM MONITOR WITH CAM AND WIPE ANALYSIS CAPABILITIES (open access)

A NEAR REAL-TIME BERYLLIUM MONITOR WITH CAM AND WIPE ANALYSIS CAPABILITIES

Science & Engineering Associates, Inc. (SEA), under contract No. DE-AC26-00NT40768, was tasked by the US Department of Energy--National Energy Technology Laboratory to develop and test a near real-time beryllium monitor for airborne and surface measurements. Recent public awareness of the health risks associated with exposure to beryllium has underscored the need for better, faster beryllium monitoring capabilities within the DOE. A near real-time beryllium monitor will offer significant improvements over the baseline monitoring technology currently in use. Whereas the baseline technology relies upon collecting an air sample on a filter and the subsequent analysis of the filter by an analytical laboratory, this effort developed a monitor that offers near real-time measurement results while work is in progress. Since the baseline typically only offers after-the-fact documentation of exposure levels, the near real-time capability provides a significant increase in worker protection. The beryllium monitor developed utilizes laser induced breakdown spectroscopy, or LIBS as the fundamental measurement technology. LIBS has been used in a variety of laboratory and field based instrumentation to provide real-time, and near-real-time elemental analysis capabilities. LIBS is an analytical technique where a pulsed high energy laser beam is focused to a point on the sample to be interrogated. The …
Date: December 1, 2002
Creator: Kendrick, D.T. & Saggese, Steven
Object Type: Report
System: The UNT Digital Library
New American Home: Las Vegas, Nevada--2003 (open access)

New American Home: Las Vegas, Nevada--2003

The New American Home is an annual showcase project designed by committee and co-sponsored by the National Association of Home Builder's National Council of the Housing Industry (NCHI) and Builder Magazine.. This year it was a building project for Amland Development.
Date: December 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
New Architectures for Micro-Total-Analytical Systems (open access)

New Architectures for Micro-Total-Analytical Systems

None
Date: December 1, 2002
Creator: GALAMBOS, PAUL C.; PONTAU, ARTHUR E.; OKANDAN, MURAT; JAMES, CONRAD D.; KIRBY, BRIAN J.; SHEPODD, TIMOTHY J. et al.
Object Type: Report
System: The UNT Digital Library
Norcal Waste Systems, Inc. (open access)

Norcal Waste Systems, Inc.

Fact sheet describes the LNG long-haul heavy-duty trucks at Norcal Waste Systems Inc.'s Sanitary Fill Company.
Date: December 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Notes on the Acceleration of Iron Ions for the Booster Applications Facility (open access)

Notes on the Acceleration of Iron Ions for the Booster Applications Facility

N/A
Date: December 1, 2002
Creator: Gardner, C. J.
Object Type: Report
System: The UNT Digital Library
Novel Elevtrode Materials For Low-Temperature Solid-Oxide Fuel Cells (open access)

Novel Elevtrode Materials For Low-Temperature Solid-Oxide Fuel Cells

Composite electrodes consisting of silver and bismuth vanadates exhibit remarkable catalytic activity for oxygen reduction at 500-550 C and greatly reduce the cathode-electrolyte (doped ceria) resistances of low temperature SOFCs, down to about 0.53 {Omega}cm{sup 2} at 500 C and 0.21 {Omega}cm{sup 2} at 550 C. The observed power densities of 231, 332, and 443 mWcm{sup -2} at 500, 525 and 550 C, respectively, make it possible to operate SOFCs at temperatures about 500 C. Using in situ potential dependent FTIR emission spectroscopy, we have found evidence for two, possibly three distinct di-oxygen species present on the electrode surface. We have successfully identified which surface oxygen species is present under a particular electrical or chemical condition and have been able to deduce the reaction mechanisms. This technique will be used to probe the gas-solid interactions at or near the TPB and on the surfaces of mixed-conducting electrodes in an effort to understand the molecular processes relevant to the intrinsic catalytic activity. Broad spectral features are assigned to the polarization-induced changes in the optical properties of the electrode surface layer. The ability of producing vastly different microstructures and morphologies of the very same material is critical to the fabrication of functionally …
Date: December 1, 2002
Creator: Lu, X.; Xia, C.; Liu, Y.; Rauch, W. & Liu, M.
Object Type: Report
System: The UNT Digital Library
Nuclear Effects in Semi-inclusive Hadron Production (open access)

Nuclear Effects in Semi-inclusive Hadron Production

Semi--inclusive production of charged hadrons ({pi}{sup +}, {pi}{sup -}, K{sup +}, K{sup -}, p, and {bar p}) in deep inelastic scattering has been studied by the HERMES experiment. Using the 27.5 GeV positron beam at DESY, the hadron multiplicity from {sup 14}N and {sup 84}Kr has been measured and compared to that from deuterium. Significant nuclear effects have been observed suggesting a modification of the quark fragmentation process in nuclei.
Date: December 1, 2002
Creator: Gaskell, David
Object Type: Article
System: The UNT Digital Library
Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 19, No. 9, Ed. 1 Sunday, December 1, 2002 (open access)

Oklahoma Firefighter (Oklahoma City, Okla.), Vol. 19, No. 9, Ed. 1 Sunday, December 1, 2002

Monthly periodical from Oklahoma City, Oklahoma published by and for members of the Oklahoma State Firefighters Association that includes news and information along with advertising.
Date: December 1, 2002
Creator: Minx, Jim
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History
The Panola Watchman (Carthage, Tex.), Vol. 129, No. 94, Ed. 1 Sunday, December 1, 2002 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 129, No. 94, Ed. 1 Sunday, December 1, 2002

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: December 1, 2002
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Pharmacia Building Q, Skokie, Illinois (open access)

Pharmacia Building Q, Skokie, Illinois

This case study was prepared as one in a series for the Laboratories for the 21st Century program, a joint endeavor of the U.S. Environmental Protection Agency and the U.S. Department of Energy's Federal Energy Management Program. The goal of this program is to foster greater energy efficiency in new and retrofit laboratory buildings in both the public and the private sectors. The energy-efficient elements of the laboratory featured in this case study-Pharmacia Corporation's new Building Q in Skokie, Illinois-include sustainable design, light-filled interior spaces for daylighting, energy-efficient fume hoods and other equipment, occupancy sensors to reduce lighting loads, and spectrally selective glazing to allow more light and less heat into the building. Water-saving fixtures are used, as well. Building Q has been certified Gold (the second highest rating) through the U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) system.
Date: December 1, 2002
Creator: unknown
Object Type: Text
System: The UNT Digital Library
Photocharge Transport and Recombination Measurements in Amorphous Silicon Films and Solar Cells by Photoconductive Frequency Mixing: Final Subcontract Report, 20 April 1998-30 June 2002 (open access)

Photocharge Transport and Recombination Measurements in Amorphous Silicon Films and Solar Cells by Photoconductive Frequency Mixing: Final Subcontract Report, 20 April 1998-30 June 2002

The tasks carried out under this subcontract focused on characterizing the charge transport, opto-electronic, and structural properties of a number of amorphous and microcrystalline semiconductors prepared by several techniques. The dominant approach to accomplish the tasks of the present phase of the program is the photoconductive frequency mixing technique. This technique enabled us to determine separately the drift mobility and the photomixing lifetime of the photogenerated carriers. The technique is based on the idea of heterodyne detection for photoconductors. When two similarly polarized monochromatic optical beams of slightly different frequencies are incident on a photoconductor, the photocurrent produced, when a dc bias is applied, will contain components resulting from the square of the sum of the incident electric fields. Consequently, a photocurrent composed of a dc and a microwave current due to the beat frequency of the incident fields will be produced; these two currents allow a separate determination of the drift mobility and the photomixing lifetime. In the present work, we improved the instrumentation of the photomixing measurements by applying bias pulses of arbitrary width and frequency. The longitudinal modes of a He-Ne laser were used to generate a beat frequency of 252 MHz; all the measurements were performed …
Date: December 1, 2002
Creator: Braunstein, R.; Boshta, M.; Sheng, S.; Kattwinkel, A.; Liebe, J. & Sun, G.
Object Type: Report
System: The UNT Digital Library
Photofission-Based, Nuclear Material Detection: Technology Demonstration (open access)

Photofission-Based, Nuclear Material Detection: Technology Demonstration

The Idaho National Engineering and Environmental Laboratory (INEEL), the Los Alamos National Laboratory (LANL), and the Advanced Research and Applications Corporation (ARACOR) [Sunnyvale, California] performed a photonuclear technology demonstration for shielded nuclear material detection during August 21–22, 2002, at the LANL TA-18 facility. The demonstration used the Pulsed Photonuclear Assessment Technique (PPAT) that focused on the application of a photofission-based, nuclear material detection method as a viable complement to the ARACOR Eagle inspection platform. The Eagle is a mobile and fully operational truck and cargo inspection system that uses a 6-MeV electron accelerator to perform real-time radiography. This imaging is performed using an approved “radiation-safe” or “cabinet safe” operation relative to the operators, inspectors, and any stowaways within the inspected vehicles. While the PPAT has been primarily developed for active interrogation, its neutron detection system also maintains a complete and effective passive detection capability.
Date: December 1, 2002
Creator: Jones, James Litton; Yoon, Woo Yong; Haskell, Kevin James; Norman, Daren Reeve; Moss, C. E.; Goulding, C. A. et al.
Object Type: Report
System: The UNT Digital Library
Phylogenetic shadowing of primate sequences to find functional regions of the human genome. (open access)

Phylogenetic shadowing of primate sequences to find functional regions of the human genome.

None
Date: December 1, 2002
Creator: Boffelli, Dario; McAuliffe, Jon; Ovcharenko, Dmitriy; Lewis, Keith D.; Ovcharenko, Ivan; Pachter, Lior et al.
Object Type: Article
System: The UNT Digital Library
Plutonium Decontamination of Uranium using CO2 Cleaning (open access)

Plutonium Decontamination of Uranium using CO2 Cleaning

A concern of the Department of Energy (DOE) Environmental Management (EM) and Defense Programs (DP), and of the Los Alamos National Laboratory (LANL) and the Lawrence Livermore National Laboratory (LLNL), is the disposition of thousands of legacy and recently generated plutonium (Pu)-contaminated, highly enriched uranium (HEU) parts. These parts take up needed vault space. This presents a serious problem for LLNL, as site limit could result in the stoppage of future weapons work. The Office of Fissile Materials Disposition (NN-60) will also face a similar problem as thousands of HEU parts will be created with the disassembly of site-return pits for plutonium recovery when the Pit Disassembly and Conversion Facility (PDCF) at the Savannah River Site (SRS) becomes operational. To send HEU to the Oak Ridge National Laboratory and the Y-12 Plant for disposition, the contamination for metal must be less than 20 disintegrations per minute (dpm) of swipable transuranic per 100 cm{sup 2} of surface area or the Pu bulk contamination for oxide must be less than 210 parts per billion (ppb). LANL has used the electrolytic process on Pu-contaminated HEU weapon parts with some success. However, this process requires that a different fixture be used for every configuration; …
Date: December 1, 2002
Creator: Blau, M
Object Type: Report
System: The UNT Digital Library
Prompt gamma activation analysis: An old technique made new (open access)

Prompt gamma activation analysis: An old technique made new

The long list of contributors to the prompt gamma activation analysis (PGAA) project is important because it highlights the broad cast of active PGAA researchers from various facilities and backgrounds. PGAA is basically a simple process in principle that was traditionally difficult in application. It is an old technique that has for years been tied to and associated exclusively with nuclear reactor facilities, which has limited its acceptance as a general, analytical tool for identifying and quantifying elements or, more precisely, isotopes, whether radioactive or nonradioactive. Field use was not a viable option.
Date: December 1, 2002
Creator: English, Jerry; Firestone, Richard; Perry, Dale; Leung, Ka-Ngo; Reijonen, Jani; Garabedian, Glenn et al.
Object Type: Report
System: The UNT Digital Library
PROTON-CONDUCTING DENSE CERAMIC MEMBRANES FOR HYDROGEN SEPARATION (open access)

PROTON-CONDUCTING DENSE CERAMIC MEMBRANES FOR HYDROGEN SEPARATION

This project is aimed at preparation of thin membranes of a modified strontium ceramic material on porous substrates with improved hydrogen permeance. The research work conducted in this reporting period was focused on studying synthesis methods for preparation of thin thulium doped strontium cerate (SrCe{sub 0.95}Tm{sub 0.05}O{sub 3}, SCTm) membranes. The following two methods were studied in the past year: (1) polymeric-gel casting and (2) dry-pressing. The polymeric-gel casting method includes preparation of mixed metal oxide gel and coating of the gel on a macroporous alumina support. Micrometer thick SCTm films of the perovskite structure can be obtained by this method. However, the deposited films are not hermetic and it may require about 50 coatings in order to obtain gas-tight SCTm films by this method. Asymmetric SCTm membranes consisting of a thick macroporous SCTm support and a thin SCTm layer can be effectively prepared by the dry-pressing method. The membranes were prepared by pressing together a thick layer of coarse SCTm powder and a thin layer of finer SCTm powder, followed by calcination and sintering under proper conditions. The asymmetric SCTm membranes have desired phase structure and are hermetic. Hydrogen permeation flux through the SCT membranes is inversely proportional to …
Date: December 1, 2002
Creator: Lin, Jerry Y.S.
Object Type: Report
System: The UNT Digital Library
The Ranger (San Antonio, Tex.), Ed. 1 Sunday, December 1, 2002 (open access)

The Ranger (San Antonio, Tex.), Ed. 1 Sunday, December 1, 2002

Student newspaper from San Antonio College in San Antonio, Texas that includes news and information on student orientation.
Date: December 1, 2002
Creator: San Antonio College
Object Type: Newspaper
System: The Portal to Texas History
Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents (open access)

Rapid Ultrasensitive Chemical-Fingerprint Detection of Chemical and Biochemical Warfare Agents

Vibrational spectra can serve as chemical fingerprints for positive identification of chemical and biological warfare molecules. The required speed and sensitivity might be achieved with surface-enhanced Raman spectroscopy (SERS) using nanotextured metal surfaces. Systematic and reproducible methods for preparing metallic surfaces that maximize sensitivity have not been previously developed. This work sought to develop methods for forming high-efficiency metallic nanostructures that can be integrated with either gas or liquid-phase chem-lab-on-a-chip separation columns to provide a highly sensitive, highly selective microanalytical system for detecting current and future chem/bio agents. In addition, improved protein microchromatographic systems have been made by the creation of acrylate-based porous polymer monoliths that can serve as protein preconcentrators to reduce the optical system sensitivity required to detect and identify a particular protein, such as a bacterial toxin.
Date: December 1, 2002
Creator: ASHBY, CAROL I.; SHEPODD, TIMOTHY J.; YELTON, WILLIAM G. & MURON, DAVID J.
Object Type: Report
System: The UNT Digital Library
Record and Document Management System (RMS) Guidelines: Issue A (open access)

Record and Document Management System (RMS) Guidelines: Issue A

RMS Guidelines defines the processes and conventions to manage both records and documents for the ASCI Verification and Validation Program at Sandia National Laboratories, employing the ASCI V&V RMS application. It is the definitive source for all information regarding the creation, submittal, use, maintenance, and disposition of records and documents. This document is also used as evidence of meeting records management requirements as stated in DOE Order 414.1A, Quality Assurance, and Sandia National Laboratories Corporate Technical Business Practice TBP-500, Records Management.
Date: December 1, 2002
Creator: Eaton, Shelley M. & Northrop-Salazar, Christine L.
Object Type: Report
System: The UNT Digital Library
Recovery and Sequestration of co2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Progress Report: July-September 2002 (open access)

Recovery and Sequestration of co2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Progress Report: July-September 2002

Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.
Date: December 1, 2002
Creator: Nakamura, T.; Olaizola, Miguel & Masutani, Stephen M.
Object Type: Report
System: The UNT Digital Library
A REDUCED ORDER MODEL OF TWO-PHASE FLOW, HEAT TRANSFER AND COMBUSTION IN CIRCULATING FLUIDIZED-BEDS (open access)

A REDUCED ORDER MODEL OF TWO-PHASE FLOW, HEAT TRANSFER AND COMBUSTION IN CIRCULATING FLUIDIZED-BEDS

This report summarizes the objectives, tasks and accomplishments of the second year of this research project. The report presents the following program deliverables: (1) visualization tools for reconstructing simulated data; (2) algorithms for reducing the partial differential equations to ordinary differential equations; and (3) visualization tools for Galerkin ordinary differential equations.
Date: December 1, 2002
Creator: Cizmas, Paul
Object Type: Report
System: The UNT Digital Library
Review of Air Flow Measurement Techniques (open access)

Review of Air Flow Measurement Techniques

Airflow measurement techniques are necessary to determine the most basic of indoor air quality questions: ''Is there enough fresh air to provide a healthy environment for the occupants of the building?'' This paper outlines airflow measurement techniques, but it does not make recommendations for techniques that should be used. The airflows that will be discussed are those within a room or zone, those between rooms or zones, such as through doorways (open or closed) or passive vents, those between the building and outdoors, and those through mechanical air distribution systems. Techniques that are highlighted include particle streak velocimetry, hot wire anemometry, fan pressurization (measuring flow at a given pressure), tracer gas, acoustic methods for leak size determination, the Delta Q test to determine duct leakage flows, and flow hood measurements. Because tracer gas techniques are widely used to measure airflow, this topic is broken down into sections as follows: decay, pulse injection, constant injection, constant concentration, passive sampling, and single and multiple gas measurements for multiple zones.
Date: December 1, 2002
Creator: McWilliams, Jennifer
Object Type: Report
System: The UNT Digital Library
A Review of Production System Models of Cognition and Example Demonstration (open access)

A Review of Production System Models of Cognition and Example Demonstration

There have been significant efforts to develop cognitively plausible software architectures of human information processing in the last three decades. This report summarizes several architectures that continue to be developed. The specific type of cognitive models developed are known as production system architectures, which refers to the characterization of knowledge in terms of procedural (''how-to'' knowledge) condition-action relationships consisting of declarative (''what'' or factual) knowledge. To illustrate the ability for these models to instantiate human cognitive performance, a simulation using ACT-R (Adaptive Control of Thought - Rational) was implemented for a supervisory control task. Correlations between simulated and human learning of the task were measured and yielded correlations as high as 0.93.
Date: December 1, 2002
Creator: BRANNON, NATHAN G.
Object Type: Report
System: The UNT Digital Library