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Measurement of the Inclusive Branching FractionsB(B^- to D^+ Pi^- Pi^-) and B(B^- to D*^+ Pi^- Pi^-)

Description: The D{sub J}{sup 0} is a family of four orbitally excited mesons: D*{sub 2}(2460){sup 0}, D{sub 1}(2420){sup 0}, D{sub 1}(j = 1/2){sup -}, and D*{sub 0}(j = 1/2){sup 0}. This dissertation presents the measurements of the inclusive branching fractions, {Beta}(B{sup -} {yields} D*{sup +}{pi}{sup -}{pi}{sup -}) and {Beta}(B{sup -} {yields} D{sup +}{pi}{sup -}{pi}{sup -}). The D{sub J}{sup 0} provides an intermediate resonance for those two modes. The data used for this analysis consists of Runs 1-… more
Date: July 17, 2007
Creator: Eschenburg, Vance Onno & U., /Mississippi
Partner: UNT Libraries Government Documents Department
open access

Optical properties and electronic structures of d- and f-electron metals and alloys, Ag-In, Ni-Cu, AuGa sub 2 , PtGa sub 2 ,. beta. prime -NiAl,. beta. prime -CoAl, CeSn sub 3 , and LaSn sub 3

Description: Optical properties and electronic structures of disordered Ag{sub 1- x}In{sub x}(x = 0.0, 0.04, 0.08, 0.12) and Ni{sub 1-x}Cu{sub x} (x = 0.0, 0.1, 0.3, 0.4) alloys and ordered AuGa{sub 2}, PtGa{sub 2}, {beta}{prime}-NiAl, {beta}{prime}-CoAl, CeSn{sub 3}, and LaSn{sub 3} have been studied. The complex dielectric functions have been determined for Ag{sub 1-x}In{sub x}, Ni{sub 1-x}Cu{sub x}, AuGa{sub 2}, and PtGa{sub 2} in the 1.2--5.5 eV region and for CeSn{sub 3} and LaSn{sub 3} in the 1.5--4.5… more
Date: October 17, 1990
Creator: Kim, Kwang Joo
Partner: UNT Libraries Government Documents Department
open access

Behavior of the Diamond Difference and Low-Order Nodal Numerical Transport Methods in the Thick Diffusion Limit for Slab Geometry

Description: The objective of this work is to investigate the thick diffusion limit of various spatial discretizations of the one-dimensional, steady-state, monoenergetic, discrete ordinates neutron transport equation. This work specifically addresses the two lowest order nodal methods, AHOT-N0 and AHOT-N1, as well as reconsiders the asymptotic limit of the Diamond Difference method. The asymptotic analyses of the AHOT-N0 and AHOT-N1 nodal methods show that AHOT-N0 does not possess the thick diffusion limit… more
Date: April 17, 2007
Creator: Gill, D. F.
Partner: UNT Libraries Government Documents Department
open access

Heavy-Ion Elastic Scattering

Description: The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with e… more
Date: April 17, 1961
Creator: Alster, Jonas
Partner: UNT Libraries Government Documents Department
open access

Exploration of Simple Analytical Approaches for Rapid Detection of Pathogenic Bacteria

Description: Many of the current methods for pathogenic bacterial detection require long sample-preparation and analysis time, as well as complex instrumentation. This dissertation explores simple analytical approaches (e.g., flow cytometry and diffuse reflectance spectroscopy) that may be applied towards ideal requirements of a microbial detection system, through method and instrumentation development, and by the creation and characterization of immunosensing platforms. This dissertation is organized into … more
Date: December 17, 2005
Creator: Rahman, Salma
Partner: UNT Libraries Government Documents Department
open access

Synthesis and Characterization of Stimuli Responsive Block Copolymers, Self-Assembly Behavior and Applications

Description: The central theme of this thesis work is to develop new block copolymer materials for biomedical applications. While there are many reports of stimuli-responsive amphiphilic [19-21] and crosslinked hydrogel materials [22], the development of an in situ gel forming, pH responsive pentablock copolymer is a novel contribution to the field, Figure 1.1 is a sketch of an ABCBA pentablock copolymer. The A blocks are cationic tertiary amine methacrylates blocked to a central Pluronic F127 triblock copo… more
Date: December 17, 2005
Creator: Determan, Michael Duane
Partner: UNT Libraries Government Documents Department
open access

Length-Limited Data Transformation and Compression

Description: Scientific computation is used for the simulation of increasingly complex phenomena, and generates data sets of ever increasing size, often on the order of terabytes. All of this data creates difficulties. Several problems that have been identified are (1) the inability to effectively handle the massive amounts of data created, (2) the inability to get the data off the computer and into storage fast enough, and (3) the inability of a remote user to easily obtain a rendered image of the data res… more
Date: May 17, 2005
Creator: Senecal, J G
Partner: UNT Libraries Government Documents Department
open access

A High-Energy, Ultrashort-Pulse X-Ray System for the Dynamic Study of Heavy, Dense Materials

Description: Thomson-scattering based x-ray radiation sources, in which a laser beam is scattered off a relativistic electron beam resulting in a high-energy x-ray beam, are currently being developed by several groups around the world to enable studies of dynamic material properties which require temporal resolution on the order of tens of femtoseconds to tens of picoseconds. These sources offer pulses that are shorter than available from synchrotrons, more tunable than available from so-called Ka sources, … more
Date: September 17, 2004
Creator: Gibson, D J
Partner: UNT Libraries Government Documents Department
open access

Mesure DU Rapport D'Embranchement ET DU Facteur Deforme DE La D_Sint_Gration b0 to Pilnu, ET D_Termination DE |Vub| Avec Unetechnique DE Reconstruction Rel_Ch_E DU Neutrinoac

Description: The authors report the results of a study of the exclusive charmless semileptonic decay, B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, undertaken with approximately 227 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. They obtain partial branching fractions in 12 bins of q{sup 2}, the momentum transfer squared, from which th… more
Date: July 17, 2007
Creator: Cote, David & U., /Montreal
Partner: UNT Libraries Government Documents Department
open access

Tuning the Superconducting Properties of Magnesium Diboride

Description: This work is presented in the following order: A review of the relevant physics and discussion of theoretical predictions for a two gap superconducting compound is given in chapter 2. Chapter 3 provides a review of the basic properties of MgB{sub 2}. Details of sample synthesis and characterization are given in chapter 4. Chapter 5 presents normal state and superconducting properties of Mg(B{sub 1-x}C{sub x}){sub 2} wires. Attempts to increase critical current densities in filaments via titaniu… more
Date: December 17, 2005
Creator: Wilke, Rudeger Heinrich Theoderich
Partner: UNT Libraries Government Documents Department
open access

Sampling for Beryllium Surface Contamination using Wet, Dry and Alcohol Wipe Sampling

Description: This research project was conducted at the National Nuclear Security Administration's Kansas City Plant, operated by Honeywell Federal Manufacturing and Technologies, in conjunction with the Safety Sciences Department of Central Missouri State University, to compare relative removal efficiencies of three wipe sampling techniques currently used at Department of Energy facilities. Efficiencies of removal of beryllium contamination from typical painted surfaces were tested by wipe sampling with dr… more
Date: December 17, 2004
Creator: Kerr, Kent
Partner: UNT Libraries Government Documents Department
open access

Measurement of the B-bar 0 to D^* l ^- nu-bar Branching Fraction with a Partial Reconstruction Technique

Description: Presented is a precise measurement of the {bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}} branching fraction using 81.47 fb{sup -1} of data collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring at the Stanford Linear Accelerator Center. The measurement was performed by partially reconstructing the D*{sup +} meson from {bar B}{sup 0} {yields} D*{sup +}{ell}{sup -}{bar {nu}}{sub {ell}} decays using only the soft pion of the D*{sup +} {yields} D{sup 0}{pi… more
Date: December 17, 2009
Creator: Sonnek, Peter & U., /Mississippi
Partner: UNT Libraries Government Documents Department
open access

Photodissociation and charge transfer dynamics of negative ions studied with femtosecond photoelectron spectroscopy

Description: This dissertation presents studies aimed at understanding the potential energy surfaces and dynamics of isolated negative ions, and the effects of solvent on each. Although negative ions play important roles in atmospheric and solution phase chemistry, to a large extent the ground and excited state potential energy surfaces of gas phase negative ions are poorly characterized, and solvent effects even less well understood. In an effort to fill this gap, the author's coworkers and the author have… more
Date: December 17, 1999
Creator: Zanni, Martin T.
Partner: UNT Libraries Government Documents Department
open access

Giant Magnetoresistive Sensors and Magnetic Labels for Chip-Scale Detection of Immunosorbent Assays

Description: The combination of giant magnetoresistive sensors, magnetic labeling strategies, and biomolecule detection is just beginning to be explored. New readout methods and assay formats are necessary for biomolecules detection to flourish. The work presented in this dissertation describes steps toward the creation of a novel detection method for bioassays utilizing giant magnetoresistive sensors as the readout method. The introduction section contains a brief review of some of the current methods of b… more
Date: December 17, 2005
Creator: Millen, Rachel Lora
Partner: UNT Libraries Government Documents Department
open access

Experiential Education in Groundwater Hydrology: Bridging the Technical-Policy-Populace Gap Final Report

Description: It is well recognized that half the countries in the world will face significant fresh water shortages in the next 20 years, due largely to growing populations and increased agricultural and industrial demands (Gleick, 1997). These shortages will significantly limit economic growth, decrease the quality of life and human health for billions of people, and could potentially lead to violence and conflict over securing scarce supplies of water. In the Middle East, groundwater represents an importa… more
Date: July 17, 2003
Creator: Tompson, A. F. B.; Maxwell, R. M.; Richardson, J. H.; El Sha'r, W. A.; Rihani, J. F. F.; El-Naser, H. et al.
Partner: UNT Libraries Government Documents Department
open access

Subunits of highly Fluorescent Protein R-Phycoerythrin as Probes for Cell Imaging and Single-Molecule Detection

Description: The purposes of our research were: (1) To characterize subunits of highly fluorescent protein R-Phycoerythrin (R-PE) and check their suitability for single-molecule detection (SMD) and cell imaging, (2) To extend the use of R-PE subunits through design of similar proteins that will be used as probes for microscopy and spectral imaging in a single cell, and (3) To demonstrate a high-throughput spectral imaging method that will rival spectral flow cytometry in the analysis of individual cells. We… more
Date: December 17, 2005
Creator: Isailovic, Dragan
Partner: UNT Libraries Government Documents Department
open access

Measurements of Branching Fraction and CP Violation inB Meson Rare Decays to Final States containing eta or eta' Mesons in the BaBar Experiment at SLAC

Description: Note that the main goal of this thesis work is the measurement of the branching fractions, charge asymmetry, and Time-Dependent CP Violation in {eta}'K{sup 0} mode. All other measurements are reported here for completion because they are connected by similar physics arguments. They are part of the Milan analysis activity, done by undergraduate students. They should not be considered as done in this thesis work. The measurements of the two body-modes {eta}{eta}, {eta}{phi}, and {eta}'{phi} are u… more
Date: July 17, 2007
Creator: Lazzaro, Alfio & U., /Milan
Partner: UNT Libraries Government Documents Department
open access

Time Dependent CP Asymmetries and Branching RatioMeasurements in Charmless Three Body B Decays at BABAR

Description: In this work we presented measurements of CP violation and decay rates of B decays in final states not involving a charm quark in the final state. In particular, the time-dependent CP asymmetries of decays which proceed through b {yields} s elementary transition is a particularly sensitive probe of physics beyond the Standard Model. In fact, even if the precise measurements of CP conserving and CP violating processes show the success of the CKM picture of the flavour physics, the sector of b {y… more
Date: July 17, 2007
Creator: Di Marco, Emanuele & U., /Rome
Partner: UNT Libraries Government Documents Department
open access

Two-dimensional nuclear magnetic resonance of quadrupolar systems

Description: This dissertation describes two-dimensional nuclear magnetic resonance theory and experiments which have been developed to study quadruples in the solid state. The technique of multiple-quantum magic-angle spinning (MQMAS) is extensively reviewed and expanded upon in this thesis. Specifically, MQMAS is first compared with another technique, dynamic-angle spinning (DAS). The similarity between the two techniques allows us to extend much of the DAS work to the MQMAS case. Application of MQMAS to … more
Date: September 17, 1997
Creator: Wang, Shuanhu
Partner: UNT Libraries Government Documents Department
open access

Search for the Rare Decay B to pi l+l- in the BaBar Experiment

Description: The rare decay B {yields} {pi}{ell}{sup +}{ell}{sup -} is the simplest manifestation of a b {yields} d{ell}{sup +}{ell}{sup -} flavor-changing neutral current (FCNC) process. This type of process only proceeds through penguin loop or box diagrams and is sensitive to physics at the electroweak scale. It can be used to constrain parameters of the Standard Model and its extensions. B {yields} {pi}{ell}{sup +}{ell}{sup -} events have not yet been observed; the branching fraction is expected to be a… more
Date: July 17, 2007
Creator: Ofte, Ingrid
Partner: UNT Libraries Government Documents Department
open access

Transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates: Catalysts for asymmetric olefin hydroamination and acceptorless alcohol decarbonylation

Description: The research presented and discussed in this dissertation involves the synthesis of transition metal complexes of oxazolinylboranes and cyclopentadienyl-bis(oxazolinyl)borates, and their application in catalytic enantioselective olefin hydroamination and acceptorless alcohol decarbonylation. Neutral oxazolinylboranes are excellent synthetic intermediates for preparing new borate ligands and also developing organometallic complexes. Achiral and optically active bis(oxazolinyl)phenylboranes are s… more
Date: December 17, 2012
Creator: Manna, Kuntal
Partner: UNT Libraries Government Documents Department
open access

Measurement of D0 lifetime with the BaBar detector

Description: This work is the result of the researchers carried out during a three years Ph.D. period in the BABAR experiment. The first chapter consists in an introduction to the theoretical aspects of the D{sup 0} meson lifetime determination and CP violation parameters, as well as an overview of the CP violation in the B sector, which is the main topic of the experiment. The description of the experimental apparatus follows with particular attention to the Silicon Vertex Tracker detector, the most critic… more
Date: December 17, 2009
Creator: Simi, Gabriele & /SLAC, /Pisa U.
Partner: UNT Libraries Government Documents Department
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