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Posthearing Questions Related to Aviation and Port Security

Description: Correspondence issued by the General Accounting Office with an abstract that begins "This letter responds to a Congressional request that we provide answers to questions relating to our September 9, 2003, testimony on transportation security."
Date: December 12, 2003
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Tilted Thick-Disk Accretion onto a Kerr Black Hole

Description: We present the first results from fully general relativistic numerical studies of thick-disk accretion onto a rapidly-rotating (Kerr) black hole with a spin axis that is tilted (not aligned) with the angular momentum vector of the disk. We initialize the problem with the solution for an aligned, constant angular momentum, accreting thick disk around a black hole with spin a/M = J/M{sup 2} = +0.9 (prograde disk). The black hole is then instantaneously tilted, through a change in the metric, by a… more
Date: December 12, 2003
Creator: Fragile, P C & Anninos, P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Static and Dynamic Criticality: Are They Different?

Description: Let us start by stating that this paper does not contain anything new. It only contains material that has been known for decades, but which is periodically forgotten. As such this paper is intended merely to refresh people's memories. We will also mention that this paper is an example of the occasional discrepancy between textbook methodologies and real world applications, in the sense that the conclusions reached here contradict what it says in most textbooks, i.e., most textbooks incorrectly … more
Date: December 12, 2003
Creator: Cullen, D E; Clouse, C J; Procassini, R & Little, R C
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Approximating spheroid inductive responses using spheres

Description: The response of high permeability ({mu}{sub r} {ge} 50) conductive spheroids of moderate aspect ratios (0.25 to 4) to excitation by uniform magnetic fields in the axial or transverse directions is approximated by the response of spheres of appropriate diameters, of the same conductivity and permeability, with magnitude rescaled based on the differing volumes, D.C. magnetizations, and high frequency limit responses of the spheres and modeled spheroids.
Date: December 12, 2003
Creator: Smith, J. Torquil & Morrison, H. Frank
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Protein Structure Recognition: From Eigenvector Analysis to Structural Threading Method

Description: In this work, they try to understand the protein folding problem using pair-wise hydrophobic interaction as the dominant interaction for the protein folding process. They found a strong correlation between amino acid sequences and the corresponding native structure of the protein. Some applications of this correlation were discussed in this dissertation include the domain partition and a new structural threading method as well as the performance of this method in the CASP5 competition. In the f… more
Date: December 12, 2003
Creator: Cao, Haibo
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Optically Detected Magnetic Resonance and Thermal Activation Spectroscopy Study of Organic Semiconductors

Description: Organic electronic materials are a new class of emerging materials. Organic light emitting devices (OLEDs) are the most promising candidates for future flat panel display technologies. The photophysical characterization is the basic research step one must follow to understand this new class of materials and devices. The light emission properties are closely related to the transport properties of these materials. The objective of this dissertation is to probe the relation between transport and p… more
Date: December 12, 2003
Creator: Kim, Chang-Hwan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects Quarterly Report: July-September 2003

Description: This report summarizes the work done during the fourth quarter of the project. Effort was directed in two areas, namely, continued further development of the model on the role of connectivity on ionic conductivity of porous bodies, including the role of grain boundaries and space charge, and its relationship to cathode polarization; and fabrication of samaria-doped ceria porous (SDC). The work on the model development involves calculation of the effect of space charge on transport through porou… more
Date: December 12, 2003
Creator: Virkar, Anil V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Organogermanium Chemistry: Germacyclobutanes and digermane Additions to Acetylenes

Description: This dissertation comprises two main research projects. The first project, presented in Chapter 1, involves the synthesis and thermochemistry of germacyclobutanes (germetanes). Four new germetanes (spirodigermetane, diallylgermetane, dichlorogermetane, and germacyclobutane) have been synthesized using a modified di-Grignard synthesis. Diallylgermetane is shown to be a useful starting material for obtaining other germetanes, particularly the parent germetane, germacyclobutane. The gas-phase ther… more
Date: December 12, 2003
Creator: Chubb, Andrew Michael
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Thermal Properties of Starch From New Corn Lines as Impacted by Environment and During Line Development

Description: The objectives of this research were to further characterize exotic by adapted corn inbreds by studying the impact of environment on their starch thermal properties, and investigating the development of starch thermal properties during kernel maturation by using differential scanning calorimetry (DSC). A method to expedite identification of unusual starch thermal traits was investigated by examining five corn kernels at a time, instead of one kernel, which the previous screening methods used. C… more
Date: December 12, 2003
Creator: Lenihan, Elizabeth M.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Organic Light-Emitting Devices (OLEDS) and Their Optically Detected Magnetic Resonance (ODMR)

Description: Organic Light-Emitting Devices (OLEDs), both small molecular and polymeric have been studied extensively since the first efficient small molecule OLED was reported by Tang and VanSlyke in 1987. Burroughes' report on conjugated polymer-based OLEDs led to another track in OLED development. These developments have resulted in full color, highly efficient (up to {approx} 20% external efficiency 60 lm/W power efficiency for green emitters), and highly bright (> 140,000 Cd/m{sup 2} DC, {approx}2,0… more
Date: December 12, 2003
Creator: Li, Gang
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Electromagnetic Wave Propagation in Two-Dimensional Photonic Crystals

Description: In this dissertation, they have undertaken the challenge to understand the unusual propagation properties of the photonic crystal (PC). The photonic crystal is a medium where the dielectric function is periodically modulated. These types of structures are characterized by bands and gaps. In other words, they are characterized by frequency regions where propagation is prohibited (gaps) and regions where propagation is allowed (bands). In this study they focus on two-dimensional photonic crystals… more
Date: December 12, 2003
Creator: Foteinopoulou, Stavroula
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Quantification of Soil Physical Properties by Using X-Ray Computerized Tomography (CT) and Standard Laboratory (STD) Methods

Description: The implementation of x-ray computerized tomography (CT) on agricultural soils has been used in this research to quantify soil physical properties to be compared with standard laboratory (STD) methods. The overall research objective was to more accurately quantify soil physical properties for long-term management systems. Two field studies were conducted at Iowa State University's Northeast Research and Demonstration Farm near Nashua, IA using two different soil management strategies. The first… more
Date: December 12, 2003
Creator: Sanchez, Maria Ambert
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Homogeneous Precipitation of Nickel Hydroxide Powders

Description: Precipitation and characterization of nickel hydroxide powders were investigated. A comprehensive precipitation model incorporating the metal ion hydrolysis, complexation and precipitation reactions was developed for the production of the powders with urea precipitation method. Model predictions on Ni{sup 2+} precipitation rate were confirmed with precipitation experiments carried out at 90 C. Experimental data and model predictions were in remarkable agreement. Uncertainty in the solubility pr… more
Date: December 12, 2003
Creator: Mavis, Bora
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Final Report for ''SOURCES AND SINKS OF CARBON FROM LAND-USE CHANGE AND MANAGEMENT: A GLOBAL SYNTHESIS'' Project Period September 15, 2001--September 14, 2003

Description: Land management and land-use change can either release carbon (as CO{sub 2}) to the atmosphere, for example when forests are converted to agricultural lands, or withdraw carbon from the atmosphere as forests grow on cleared lands or as management practices sequester carbon in soil. The purpose of this work was to calculate the annual sources and sinks of carbon from changes in land use and management, globally and for nine world regions, over the period 1850 to 2000. The approach had three comp… more
Date: December 12, 2003
Creator: Houghton, R.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High Level Waste Tank Gamma Profiling

Description: Cleanup at the Savannah River Site brings with it the need to clean out and close down the radioactive waste tanks constructed in support of the fuel rod dissolution process. An innovative technique for assaying waste tanks has been developed at the Savannah River Site. The technique uses a gamma detector in the annular space between the inner and outer walls of double walled tanks. Unique shielding, counting electronics, and deployment techniques were developed to facilitate mapping interstiti… more
Date: December 12, 2003
Creator: Moore, F.S. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Melter Off-Gas Flammability Analysis

Description: The objective of this work was to develop predictive models to assess offgas flammability for a low activity radioactive waste melter. The models had to be comprehensive enough to explicitly describe the effects of key melter operating variables such as total organic carbon in the feed, melter air purge and vapor space temperature. Once validated against pilot melter data, these models were used to simulate a series of safety scenarios involving over-batching of sugar, used as a reducing agent,… more
Date: December 12, 2003
Creator: Smith, FG III
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Process Development for Destruction of Tetraphenylborate in SRS Tank 48H

Description: SRTC investigated several options to remediate the contents of Tank 48H. Three options were examined: the Fenton reaction, Hydrolysis and Catalysis. Each option was investigated using a series of six reactions. These reactions were exploratory in nature; optimization is planned for a later date. Each experiment was conducted over a two-week period. The results of the experiments indicate that each process is a viable in-tank option, but there are limitations (discussed below) that must be addre… more
Date: December 12, 2003
Creator: Peters, T.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Low Cycle Fatigue Analysis of Storage Canisters Due to Expansion of Contents

Description: Qualification of storage canisters due to the expansion behavior of plutonium metal during phase transitions requires a combined experimental and analytical modeling effort. Tests were conducted at Los Alamos National Laboratory to define the expansion behavior of plutonium metal during the alpha-beta-gamma phase transitions. Test results showed that the expansion is anisotropic due to the container wall constraint. The plutonium expansion parameters were calculated from test data, and combined… more
Date: December 12, 2003
Creator: Flanders, H.E. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic consistency of the equation of state of strongly interacting matter

Description: Addressing strongly interacting matter in the region of energy density where the hadronic gas phase coexists with the quark-gluon plasma phase, we discuss how thermodynamic consistency can be used to constrain the equation of state for uniform matter and we illustrate the method by constructing a T{sub c}-dependent family of thermodynamically consistent equations of state based on simple spline interpolations between the gas and plasma phases.
Date: December 12, 2003
Creator: Randrup, Jorgen & Ruuskanen, Vesa P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

SPA-LEED Study of the Morphology and Nucleation of a Novel Growth Mode and the ''devil's staircase'' on Pb/Si(111)

Description: This thesis was developed to address the following questions for the Pb/Si(111) system: (1) Is it possible to control the nano-structure growth by changing the initial substrate; (2) is the nucleation theory applicable to the case of the 7-step growth mode; and (3) what phase or phases could be formed between coverage 6/5 ML and 4/3 ML? The first question was answered in chapter 2, different growth results were observed for different initial substrate, suggesting the possibility of controlling … more
Date: December 12, 2003
Creator: Yeh, Wang-Chi Vincent
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Bioanalytical Applications of Real-Time ATP Imaging Via Bioluminescence

Description: The research discussed within involves the development of novel applications of real-time imaging of adenosine 5'-triphosphate (ATP). ATP was detected via bioluminescence and the firefly luciferase-catalyzed reaction of ATP and luciferin. The use of a microscope and an imaging detector allowed for spatially resolved quantitation of ATP release. Employing this method, applications in both biological and chemical systems were developed. First, the mechanism by which the compound 48/80 induces rel… more
Date: December 12, 2003
Creator: Gruenhagen, Jason Alan
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

Final Project Report

Description: This report provides a description of the main accomplishments of the EMSP funded research, including products such as conference presentations and publications (including those still in preparation). The purpose of this study was to better understand the chemical interactions between dissolved aqueous contaminants and carbonate minerals occurring as coatings on mineral grains in the vadose zone beneath the Hanford reserve. This information is important for construction of improved reactive tra… more
Date: December 12, 2003
Creator: Eggleston, Carrick M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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