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CHEMISTRY OF +1 IODINE IN ALKALINE SOLUTION

Description: The iodine species formed either by adding hypochlorite to a basic iodide solution or by adding triiodide to sodium hydroxide, was identified as hypoiodite ion. The absorption spectrum of IO{sup -} was investigated in the wavelength range from 450 m{micro} to 280 m{micro}. The kinetics of the reaction I{sup -} + ClO{sup -} = IO{sup -} + Cl{sup -} was studied spectrophotometrically in alkaline solution. The forward rate law was found to be d(IO{sup -})/dt = k(I{sup -})(ClO{sup -})/OH{sup -}. At … more
Date: June 2, 1958
Creator: Chia, Yuan-tsan.
Partner: UNT Libraries Government Documents Department
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Beta-Spectra of the Mirror Nuclei with A = 19 to 39

Description: Thesis presenting data taken on experimental nuclear magnetic moments for beta spectra of the mirror nuclei with A-19 to 39.
Date: August 2, 1957
Creator: Welch, Jasper A., Jr.
Partner: UNT Libraries Government Documents Department
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Topics in particle physics and cosmology

Description: The Standard Model of particle physics, together with the Big Bang model of the early universe, constitute a framework which encompasses our current understanding of fundamental laws and beginning of our universe. Despite recent speculative trends, quantum field theory remains the theoretical tool of choice for investigating new physics either at high energy colliders, or in the early universe. In this dissertation, several field theoretic phenomena relevant to cosmology or particle physics are… more
Date: August 2, 1991
Creator: Hsu, S. D. H.
Partner: UNT Libraries Government Documents Department
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Multitasking mesoporous nanomaterials for biorefinery applications

Description: Mesoporous silica nanoparticles (MSNs) have attracted great interest for last two decades due to their unique and advantageous structural properties, such as high surface area, pore volume, stable mesostructure, tunable pore size and controllable particle morphology. The robust silica framework provides sites for organic modifications, making MSNs ideal platforms for adsorbents and supported organocatalysts. In addition, the pores of MSNs provide cavities/ channels for incorporation of metal an… more
Date: May 2, 2013
Creator: Kandel, Kapil
Partner: UNT Libraries Government Documents Department
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Imaging gene expression in real-time using aptamers

Description: Signal transduction pathways are usually activated by external stimuli and are transient. The downstream changes such as transcription of the activated genes are also transient. Real-time detection of promoter activity is useful for understanding changes in gene expression, especially during cell differentiation and in development. A simple and reliable method for viewing gene expression in real time is not yet available. Reporter proteins such as fluorescent proteins and luciferase allow for n… more
Date: November 2, 2012
Creator: Shin, Il Chung
Partner: UNT Libraries Government Documents Department
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Single crystal Processing and magnetic properties of gadolinium nickel

Description: GdNi is a rare earth intermetallic material that exhibits very interesting magnetic properties. Spontaneous magnetostriction occurs in GdNi at T{sub C}, on the order of 8000ppm strain along the c-axis and only until very recently the mechanism causing this giant magnetostriction was not understood. In order to learn more about the electronic and magnetic structure of GdNi, single crystals are required for anisotropic magnetic property measurements. Single crystal processing is quite challenging… more
Date: November 2, 2012
Creator: Shreve, Andrew John
Partner: UNT Libraries Government Documents Department
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Study of B-Meson Decays to Final States with a Single Charm Baryon

Description: A study of B-meson decays to final states with a single charm baryon is presented based on data recorded by the BABAR detector at the Stanford Linear Accelerator Center. Although the B meson is the lightest bottom-flavored meson, it is heavy enough to decay to a baryon made of three quarks and an antibaryon made of three antiquarks. By studying the baryonic weak decays of the B meson, we can investigate baryon production mechanisms in heavy meson decays. In particular, we measure the rates of t… more
Date: June 2, 2009
Creator: Majewski, Stephanie A.
Partner: UNT Libraries Government Documents Department
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In situ nanoindentation in a transmission electron microscope

Description: This dissertation presents the development of the novel mechanical testing technique of in situ nanoindentation in a transmission electron microscope (TEM). This technique makes it possible to simultaneously observe and quantify the mechanical behavior of nano-scale volumes of solids.
Date: December 2, 2002
Creator: Minor, Andrew M.
Partner: UNT Libraries Government Documents Department
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Synthesis of main group, rare-earth, and d{sup 0} metal complexes containing beta-hydrogen

Description: A series of organometallic compounds containing the tris(dimethylsilyl)methyl ligand are described. The potassium carbanions KC(SiHMe{sub 2}){sub 3} and KC(SiHMe{sub 2}){sub 3}TMEDA are synthesized by deprotonation of the hydrocarbon HC(SiHMe{sub 2}){sub 3} with potassium benzyl. KC(SiHMe{sub 2}){sub 3}TMEDA crystallizes as a dimer with two types of three-center-two-electron KH- Si interactions. Homoleptic Ln(III) tris(silylalkyl) complexes containing β-SiH groups M{C(SiHMe{sub 2}){sub 3}}{sub … more
Date: May 2, 2013
Creator: Yan, Ka King
Partner: UNT Libraries Government Documents Department
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Computational fluid dynamic modeling of fluidized-bed polymerization reactors

Description: Polyethylene is one of the most widely used plastics, and over 60 million tons are produced worldwide every year. Polyethylene is obtained by the catalytic polymerization of ethylene in gas and liquid phase reactors. The gas phase processes are more advantageous, and use fluidized-bed reactors for production of polyethylene. Since they operate so close to the melting point of the polymer, agglomeration is an operational concern in all slurry and gas polymerization processes. Electrostatics and … more
Date: November 2, 2012
Creator: Rokkam, Ram
Partner: UNT Libraries Government Documents Department
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United abominations: Density functional studies of heavy metal chemistry

Description: Carbonyl and nitrile addition to uranyl (UO{sup 2}{sup 2+}) are studied. The competition between nitrile and water ligands in the formation of uranyl complexes is investigated. The possibility of hypercoordinated uranyl with acetone ligands is examined. Uranyl is studied with diactone alcohol ligands as a means to explain the apparent hypercoordinated uranyl. A discussion of the formation of mesityl oxide ligands is also included. A joint theory/experimental study of reactions of zwitterionic b… more
Date: April 2, 2012
Creator: Schoendorff, George
Partner: UNT Libraries Government Documents Department
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Large-Eddy Simulation of the Evolving Stable Boundary Layer Over Flat Terrain

Description: The stable boundary layer (SBL) in the atmosphere is of considerable interest because it is often the worse case scenario for air pollution studies and health effect assessments associated with the accidental release of toxic material. Traditional modeling approaches used in such studies do not simulate the non-steady character of the velocity field, and hence often overpredict concentrations while underpredicting spatial coverage of potentially harmful concentrations of airborne material. The … more
Date: January 2, 2002
Creator: Townsend, Richard Townsend
Partner: UNT Libraries Government Documents Department
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RHEED studies of Ag/Si(111) growth at low temperatures

Description: This thesis showed that it is possible to achieve well ordered growth at low temperatures when chaing fluxes during the course of the deposition. It was also demonstrated that nucleation theory fails to predict or explain at least part of the results, in particular when deposition takes place at an initially low rate, with presumably a relatively low nucleation density, followed by a change to a high flux rate. This points to an inherent lack of nucleation theory; alternative explanations are p… more
Date: January 2, 1996
Creator: Koehler, U.
Partner: UNT Libraries Government Documents Department
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A new post-column reactor-laser induced fluorescence detector for capillary electrophoresis

Description: Capillary zone electrophoresis (CZE), a powerful separation method based on the differential migration of charged species under the influence of an electric field, has been widely used for separations covering from small ions to big biomolecules. Chapter 1 describes the method, then discusses detection of the separated analytes by laser induced fluorescence and by chemical derivatization, and the use of O-phthaldialdehyde (OPA) as a post-column reagent. Chapter 2 describes a post-column reactor… more
Date: January 2, 1996
Creator: Liling, Zhang
Partner: UNT Libraries Government Documents Department
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Rare earth chalcogenides for use as high temperature thermoelectric materials

Description: In the first part of the thesis, the electric resistivity, Seebeck coefficient, and Hall effect were measured in X{sub y}(Y{sub 2}S{sub 3}){sub 1-y} (X = Cu, B, or Al), for y = 0.05 (Cu, B) or 0.025-0.075 for Al, in order to determine their potential as high- temperature (HT)(300-1000 C) thermoelectrics. Results indicate that Cu, B, Al- doped Y{sub 2}S{sub 3} are not useful as HT thermoelectrics. In the second part, phase stability of {gamma}-cubic LaSe{sub 1.47-1.48} and NdSe{sub 1.47} was mea… more
Date: January 2, 1996
Creator: Michiels, J.
Partner: UNT Libraries Government Documents Department
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A cross section measurement of charm hyperons {Xi}{sub c}{sup +} and {Xi}{sub c}{sup 0} in 250 GeV p/K/{pi}-nucleon interactions

Description: Fermilab Experiment 769 used a charge-selected, hadron beam of mean energy 250 GeV/c, composed of pions, kaons, and protons, impinging on beryllium, aluminum, copper and tungsten targets. Using a sample of approximately 4000 {Xi}{sub s}{sup {minus}} {yields} {Lambda}{sup 0}{pi}{sup {minus}} decays, measurements of the charm baryon forward cross sections times branching ratio {pi}{sup {+-}}N {yields} {Xi}{sub c}{sup +}X and {pi}{sup {+-}}N {yields} {Xi}{sub c}{sup 0}X are presented. Upper limits… more
Date: May 2, 1995
Creator: Francisco, J. & Vergara, A.
Partner: UNT Libraries Government Documents Department
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Laser-plasma interactions relevant to Inertial Confinement Fusion

Description: Research into laser-driven inertial confinement fusion is now entering a critical juncture with the construction of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL). Many of the remaining unanswered questions concerning NIF involve interactions between lasers and plasmas. With the eventual goal of fusion power in mind, laser-plasma interactions relevant to laser fusion schemes is an important topic in need of further research. This work experimentally addres… more
Date: November 2, 1998
Creator: Wharton, Kenneth Bradford
Partner: UNT Libraries Government Documents Department
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