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Towards the resolution of the solar neutrino problem

Description: A number of experiments have accumulated over the years a large amount of solar neutrino data. The data indicate that the observed solar neutrino flux is significantly smaller than expected and, furthermore, that the electron neutrino survival probability is energy dependent. This ''solar neutrino problem'' is best solved by assuming that the electron neutrino oscillates into another neutrino species. Even though one can classify the solar neutrino deficit as strong evidence for neutrino oscill… more
Date: August 29, 2000
Creator: Friedland, Alexander
Partner: UNT Libraries Government Documents Department
open access

A simulation-based study of HighSpeed TCP and its deployment

Description: The current congestion control mechanism used in TCP has difficulty reaching full utilization on high speed links, particularly on wide-area connections. For example, the packet drop rate needed to fill a Gigabit pipe using the present TCP protocol is below the currently achievable fiber optic error rates. HighSpeed TCP was recently proposed as a modification of TCP's congestion control mechanism to allow it to achieve reasonable performance in high speed wide-area links. In this research, simu… more
Date: April 29, 2003
Creator: Souza, Evandro de
Partner: UNT Libraries Government Documents Department
open access

Bulk gold catalyzed oxidation reactions of amines and isocyanides and iron porphyrin catalyzed N-H and O-H bond insertion/cyclization reactions of diamines and aminoalcohols

Description: This work involves two projects. The first project entails the study of bulk gold as a catalyst in oxidation reactions of isocyanides and amines. The main goal of this project was to study the activation and reactions of molecules at metal surfaces in order to assess how organometallic principles for homogeneous processes apply to heterogeneous catalysis. Since previous work had used oxygen as an oxidant in bulk gold catalyzed reactions, the generality of gold catalysis with other oxidants was … more
Date: December 29, 2011
Creator: Klobukowski, Erik
Partner: UNT Libraries Government Documents Department
open access

Adaptations in Electronic Structure Calculations in Heterogeneous Environments

Description: Modern quantum chemistry deals with electronic structure calculations of unprecedented complexity and accuracy. They demand full power of high-performance computing and must be in tune with the given architecture for superior e#14;ciency. To make such applications resourceaware, it is desirable to enable their static and dynamic adaptations using some external software (middleware), which may monitor both system availability and application needs, rather than mix science with system-related cal… more
Date: November 29, 2011
Creator: Talamudupula, Sai
Partner: UNT Libraries Government Documents Department
open access

Chromosomal Aberrations in a Natural Population of Chironomus Tentans Exposed to Chronic Low-Level Environmental Radiation

Description: The salivary gland chromosomes of Chironomus tentans larvae collected from White Oak Creek, an area contaminated by radioactive waste from the Oak Ridge National Laboratory, and from six uncontaminated areas were examined for chromosomal aberrations. White Oak Creek populations were exposed to absorbed doses as high as 230 rads per year or about 1000 times background. Chromosomal maps were constructed to make a general comparison of the banding pattern of the salivary chromosomes of the C. tent… more
Date: January 29, 1964
Creator: Blaylock, B. G.; Auerbach, S. I. & Nelson, D. J.
Partner: UNT Libraries Government Documents Department
open access

Developing New Nanoprobes from Semiconductor Nanocrystals

Description: In recent years, semiconductor nanocrystal quantum dots havegarnered the spotlight as an important new class of biological labelingtool. Withoptical properties superior to conventional organicfluorophores from many aspects, such as high photostability andmultiplexing capability, quantum dots have been applied in a variety ofadvanced imaging applications. This dissertation research goes along withlarge amount of research efforts in this field, while focusing on thedesign and development of new n… more
Date: May 29, 2006
Creator: Fu, Aihua
Partner: UNT Libraries Government Documents Department
open access

Study of Charmed Baryon Sigma(C)(2800) Production at the BaBar Experiment

Description: This dissertation reports on a study of search for an orbitally excited state of charmed baryons {Sigma}{sub c}{sup 0}(2800) and {Sigma}{sub c}{sup ++}(2800). They measure the widths, momentum spectrum and production cross-section for these states decaying into a {Lambda}{sub c}{sup +} and a charged {pi}. The analysis uses 230 fb{sup -1} of data collected at BABAR detector operating at PEP-II collider at Stanford Linear Accelerator Center. The data is collected in the region of {Upsilon}(4S) an… more
Date: February 29, 2008
Creator: Ahmded, Shamona
Partner: UNT Libraries Government Documents Department
open access

Parametric Model for Astrophysical Proton-Proton Interactions and Applications

Description: Observations of gamma-rays have been made from celestial sources such as active galaxies, gamma-ray bursts and supernova remnants as well as the Galactic ridge. The study of gamma rays can provide information about production mechanisms and cosmic-ray acceleration. In the high-energy regime, one of the dominant mechanisms for gamma-ray production is the decay of neutral pions produced in interactions of ultra-relativistic cosmic-ray nuclei and interstellar matter. Presented here is a parametric… more
Date: January 29, 2008
Creator: Karlsson, Niklas
Partner: UNT Libraries Government Documents Department
open access

MEASUREMENTS OF DIRECT CP VIOLATION AND CONSTRAINT ON THE CKM TRIANGLE IN B->K*pi DECAYS

Description: We constrain the apex of the Cabibbo-Kobayashi-Maskawa unitarity triangle with measurements of B {yields} K*{pi} amplitudes from analyses of B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} and B{sup 0} {yields} K{sub S}{pi}{sup +}{pi}{sup -} decays. This constraint is consistent with the world average. The B{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0} decay mode is reconstructed from a sample of 454 million B{sup 0}{bar B}{sup 0} events collected by the BABAR detector at SLAC. We measure di… more
Date: April 29, 2010
Creator: Wagner, Andrew Phillips
Partner: UNT Libraries Government Documents Department
open access

Searches for the Theta_s(1540)+ Strange-Pentaquark Candidate in e+e- Annihilation, Hadroproduction and Electroproduction with the BaBar Detector

Description: Since early in 2003, several experiments have presented evidence for the existence of a positive strangeness baryon state of mass around 1540 MeV/c{sup 2} and width <8 MeV, the {Theta}(1540), which decays to K{sup +}n and K{sup 0}p. Such a state has minimum quark content udud{bar s} and consequently has been interpreted as the S = +1 member of the anti-decuplet of pentaquark states proposed by Diakonov et al. Subsequently, the NA49 experiment presented evidence for the S = -2 member of the a… more
Date: July 29, 2009
Creator: Coleman, Jonathan P.
Partner: UNT Libraries Government Documents Department
open access

I: Low Frequency NMR and NQR Using a dc SQUID. II: Variable-temperature 13C CP/MAS of Organometallics

Description: NMR and NQR at low frequencies are difficult prospects due to small nuclear spin polarization. Furthermore, the sensitivity'of the inductive pickup circuitry of standard spectrometers is reduced as the frequency is lowered. I have used a cw-SQUID (Superconducting QUantum Interference Device) spectrometer, which has no such frequency dependence, to study the local atomic environment of {sup 14}N via the quadrupolar interaction. Because {sup 14}N has spin I = 1 and a 0-6 MHz frequency range, it i… more
Date: November 29, 1995
Creator: Ziegeweid, M.A.
Partner: UNT Libraries Government Documents Department
open access

Direct Contact Condensation With Two Immiscible Fluids

Description: 87p. The theory, design techniques, and relative economics are presented for three basically different direct-contact condensation processes involving fluids whose condensed phases are immiscible. In the specific system developed for the study, Aroclor 1248 (Monsanto Chemical Corporation) and steam were used. The processes investigated include the injection, and the induction of steam into a highvelocity stream of Aroclor in the throat section of a Venturi. The bubbling of steam into a low-velo… more
Date: June 29, 1962
Creator: Lackey, D. L.
Partner: UNT Libraries Government Documents Department
open access

Toward a New Generation of Student Outcome Measures: Connecticut's Common Core of Learning Assessment

Description: A report, "Toward a New Generation of Student Outcome Measures: Connecticut's Common Core of Learning Assessment" by Joan Boykoff Baron, Pascal D. Forgione, Jr. Douglas A. Rindone, Hanna Kruglanksi and Bruce Davey. Connecticut State, Department of Education, Division of Research, Evaluation and Assessment. 165 Capitol Avenue - Room 340. Hartford, Connecticut. Presented at American Education Association Annual Meeting, San Francisco, California. Part of Symposium 28.01 Beyond Effective Schools: … more
Date: March 29, 1989
Creator: Baron, Joan Boykoff; Forgione, Pascal D., Jr.; Rindone, Douglas A.; Kruglanksi, Hannah & Davey, Bruce
Partner: UNT Libraries Special Collections
open access

Calculations of Bottom Quark Production at Hadron Colliders

Description: This thesis studies Monte Carlo simulations of QCD heavy flavor production processes (p{bar p} {yields} Q({anti Q})X) at hadron colliders. ISAJET bottom quark cross-sections are compared to the O({alpha} {sub s}{sup 3}) perturbative calculation of Nason, Dawson, and Ellis. These Monte Carlo cross-sections are computed from data samples which use different parton distribution functions and physics parameters. Distributions are presented in the heavy quark`s transverse momentum and rapidity. Corr… more
Date: June 29, 1991
Creator: Kuebel, D.
Partner: UNT Libraries Government Documents Department
open access

Experimental Studies of the Stimulated Brillouin Scattering Instability in the Saturated Regime

Description: An experimental study of the stimulated Brillouin scattering (SBS) instability has investigated the effects of velocity gradients and kinetic effects on the saturation of ion-acoustic waves in a plasma. For intensities less than I < 1.5 x 10{sup 15} W cm{sup -2}, the SBS instability is moderated primarily by velocity gradients, and for intensities above this threshold, nonlinear trapping is invoked to saturate the instability. We report direct evidence of detuning of SBS by a velocity gradie… more
Date: October 29, 2002
Creator: Froula, D
Partner: UNT Libraries Government Documents Department
open access

Analysis of Hypothetical Promoter Domains of DKFZp564A1164, NPHS1 and HSPOX1 Genes

Description: For this study, a high throughput method for identifying and testing regulatory elements was examined. In addition, the validity of promoters predicted by FirstEF was tested. It was found that by combining computer based promoter and first exon predictions from FirstEF (Davuluri et al., 2001) with PCR-based cloning to generate luciferase reporter constructs, and by testing reporter activity in cultured mammalian cells plated in a 96 well format one could identify promoter activity in a relative… more
Date: November 29, 2003
Creator: Hammond, S S
Partner: UNT Libraries Government Documents Department
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