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Thermochemical investigations of crystalline solutes in non-electrolyte solutions: Mathematical representation of solubility data and the development of predictive solubility equations in systems with specific and non-specific interactions.

Description: Understanding the thermodynamic properties of multicomponent mixtures is of critical importance in many chemical and industrial applications. Experimental measurements become progressively difficult as the number of solution components increases -- producing the need for predictive models. Problems in development of predictive models arise if the mixture has one or more components that interact through molecular complexation or association. Experimental solubilities of anthracene and pyrene di… more
Date: May 2008
Creator: Zvaigzne, Anita Ilze
Partner: UNT Libraries
open access

Observation of Disappearance of Muon Neutrinos in the NuMI Beam

Description: The Main Injector Neutrino Oscillation Search (MINOS) is a two detector long-baseline neutrino experiment designed to study the disappearance of muon neutrinos. MINOS will test the {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation hypothesis and measure precisely {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} oscillation parameters. The source of neutrinos for MINOS experiment is Fermilab's Neutrinos at the Main Injector (NuMI) beamline. The energy spectrum and the composition of the… more
Date: May 1, 2008
Creator: Pavlovic, Zarko
Partner: UNT Libraries Government Documents Department
open access

Two-photon Photoemission of Organic Semiconductor Molecules on Ag(111)

Description: Angle- and time-resolved two-photon photoemission (2PPE) was used to study systems of organic semiconductors on Ag(111). The 2PPE studies focused on electronic behavior specific to interfaces and ultrathin films. Electron time dynamics and band dispersions were characterized for ultrathin films of a prototypical n-type planar aromatic hydrocarbon, PTCDA, and representatives from a family of p-type oligothiophenes.In PTCDA, electronic behavior was correlated with film morphology and growth modes… more
Date: May 15, 2008
Creator: Yang, Aram & Yang, Aram
Partner: UNT Libraries Government Documents Department
open access

Search for pair production of scalar top quarks in jets and missing transverse energy channel with the D0 detector

Description: This dissertation describes a search for the pair production of scalar top quarks, {tilde t}{sub 1}, using a luminosity of 995 pb{sup -1} of data collected in p{bar p} collisions with the D0 detector at the Fermilab Tevatron Collider at a center-of-mass energy {radical}s = 1.96 TeV. Both scalar top quarks are assumed to decay into a charm quark and a neutralino, {tilde {chi}}{sub 1}{sup 0}, where {tilde {chi}}{sub 1}{sup 0} is the lightest supersymmetric particle. This leads to a final state wi… more
Date: May 1, 2008
Creator: Shamim, Mansoora & U., /Kansas State
Partner: UNT Libraries Government Documents Department
open access

Search for pair production of second generation scalar leptoquarks in ppbar collisions at the Tevatron

Description: As predicted by numerous extensions of the Standard Model, leptoquarks (LQ) are hypothetical bosons allowing lepton-quark transitions. Under the assumption that they couple only to quarks and leptons of the same generation, three generations of leptoquarks can be distinguished. The search for the pair production of second generation scalar leptoquarks has been carried out in p{bar p} collisions at {radical}s = 1.96TeV, using an integrated luminosity of 1 fb{sup -1} collected by the D0 experimen… more
Date: May 1, 2008
Creator: Calfayan, Philippe
Partner: UNT Libraries Government Documents Department
open access

Nanocrystal Bioassembly: Asymmetry, Proximity, and Enzymatic Manipulation

Description: Research at the interface between biomolecules and inorganic nanocrystals has resulted in a great number of new discoveries. In part this arises from the synergistic duality of the system: biomolecules may act as self-assembly agents for organizing inorganic nanocrystals into functional materials; alternatively, nanocrystals may act as microscopic or spectroscopic labels for elucidating the behavior of complex biomolecular systems. However, success in either of these functions relies heavily up… more
Date: May 1, 2008
Creator: Claridge, Shelley A
Partner: UNT Libraries Government Documents Department
open access

Measurement of the Top Quark Mass at CDF Using the Template Method in the Lepton + Jets Channel

Description: A measurement of the top quark mass in p{bar p} collisions at {radical}s = 1.96 TeV is presented. The analysis uses a template method, in which the overconstrained kinematics of the Lepton+Jets channel of the t{bar t} system are used to measure a single quantity, the reconstructed top quark mass, that is strongly correlated with the true top quark mass. in addition, the dijet mass of the hadronically decaying W boson is used to constrain in situ the uncertain jet energy scale in the CDF detecto… more
Date: May 1, 2008
Creator: Adelman, Jahred A.
Partner: UNT Libraries Government Documents Department
open access

Probing the Energy Transfer Dynamics of Photosynthetic Reaction Center Complexes Through Hole-Burning and Single-Complex Spectroscopy

Description: Photosynthesis is the process by which light energy is used to drive reactions that generate sugars to supply energy for cellular processes. It is one of the most important fundamental biological reactions and occurs in both prokaryotic (e.g. bacteria) and eukaryotic (e.g. plants and algae) organisms. Photosynthesis is also remarkably intricate, requiring the coordination of many different steps and reactions in order to successfully transform absorbed solar energy into a biochemical usable for… more
Date: May 1, 2008
Creator: Riley, Kerry
Partner: UNT Libraries Government Documents Department
open access

Quantum Dynamical Behaviour in Complex Systems - A Semiclassical Approach

Description: One of the biggest challenges in Chemical Dynamics is describing the behavior of complex systems accurately. Classical MD simulations have evolved to a point where calculations involving thousands of atoms are routinely carried out. Capturing coherence, tunneling and other such quantum effects for these systems, however, has proven considerably harder. Semiclassical methods such as the Initial Value Representation (SC-IVR) provide a practical way to include quantum effects while still utilizing… more
Date: May 22, 2008
Creator: Gliebe, Cheryn E & Ananth, Nandini
Partner: UNT Libraries Government Documents Department
open access

Inclusive Rates and Spectra of the Lambda, Cascade, and Omega Hyperons atBaBar

Description: We employ Runs 1-4 off-peak data sample (about 21.5 fb{sup -1}) to produce the current world-best spectra and production rates measurements for three strangely-flavored baryons: the {Lambda} hyperon, the cascade hyperon, and the {Omega} hyperon. These improved measurements shall enable theoretical and phenomelogical workers to generate more realistic models for the hadronization process, currently one of the unresolved problem areas in the standard model of particle physics. This analysis was c… more
Date: May 19, 2008
Creator: Chien, Andrew L.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the production rate of the charm jet recoiling against the W boson using the D0 detector at the Fermilab Tevatron Collider

Description: This dissertation describes a measurement of the rate of associated production of the W boson with the charm jet in the proton and anti-proton collisions at the center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider. The measurement has direct sensitivity to the strange quark content inside the proton. A direct measurement of the momentum distribution of the strange quark inside the proton is essential for a reliable calculation of new physics signal as well as the background proce… more
Date: May 1, 2008
Creator: Ahsan, Mahsana & U., /Kansas State
Partner: UNT Libraries Government Documents Department
open access

Measurement of top quark mass in the all hadronic channel in s**(1/2) = 1.96 TeF, ppbar collisions at D0

Description: A measurement of the top quark mass in proton-antiproton collisions at {radical}s = 1.96 TeV using 1040fb{sup -1} of data collected in D detector at Fermilab is presented. This analysis focuses on the all-hadronic decay mode of the top quark and therefore only events with six or more calorimeter jets in the final state are considered.
Date: May 1, 2008
Creator: Lam, David Wai Kui & U., /Notre Dame
Partner: UNT Libraries Government Documents Department
open access

Intense Ion Beam for Warm Dense Matter Physics

Description: The Neutralized Drift Compression Experiment (NDCX) at Lawrence Berkeley National Laboratory is exploring the physical limits of compression and focusing of ion beams for heating material to warm dense matter (WDM) and fusion ignition conditions. The NDCX is a beam transport experiment with several components at a scale comparable to an inertial fusion energy driver. The NDCX is an accelerator which consists of a low-emittance ion source, high-current injector, solenoid matching section, induct… more
Date: May 23, 2008
Creator: Coleman, Joshua Eugene
Partner: UNT Libraries Government Documents Department
open access

Model Independent Search For New Physics At The Tevatron

Description: The Standard Model of elementary particles can not be the final theory. There are theoretical reasons to expect the appearance of new physics, possibly at the energy scale of few TeV. Several possible theories of new physics have been proposed, each with unknown probability to be confirmed. Instead of arbitrarily choosing to examine one of those theories, this thesis is about searching for any sign of new physics in a model-independent way. This search is performed at the Collider Detector at F… more
Date: May 1, 2008
Creator: Choudalakis, Georgios
Partner: UNT Libraries Government Documents Department
open access

Odd-Z Transactinide Compound Nucleus Reactions Including the Discovery of 260Bh

Description: Several reactions producing odd-Z transactinide compound nuclei were studiedwith the 88-Inch Cyclotron and the Berkeley Gas-Filled Separator at the LawrenceBerkeley National Laboratory. The goal was to produce the same compound nucleus ator near the same excitation energy with similar values of angular momentum via differentnuclear reactions. In doing so, it can be determined if there is a preference in entrancechannel, because under these experimental conditions the survival portion of Swiatec… more
Date: May 14, 2008
Creator: Nelson, Sarah L & Nelson, Sarah L
Partner: UNT Libraries Government Documents Department
open access

Measurement of electroweak single top quark production in proton-antiproton collisions at 1.96 TeV

Description: The top quark is an extremely massive fundamental particle that is predominantly produced in pairs at particle collider experiments. The Standard Model of particle physics predicts that top quarks can also be produced singly by the electroweak force; however, this process is more difficult to detect because it occurs at a smaller rate and is more difficult to distinguish from background processes. The cross section of this process is related to the Cabbibo-Kobayashi-Maskawa matrix element |V{su… more
Date: May 1, 2008
Creator: Dong, Peter Joseph
Partner: UNT Libraries Government Documents Department
open access

Measurement of the W boson production charge asymmetry in p pbar collisions

Description: We present a measurement of the W boson production charge asymmetry using the W {yields} e{nu} decay channel. We use data collected the Collider Detector at Fermilab (CDF) from p{bar p} collisions at {radical}s = 1.96 TeV. The data were collected up to February 2006 (Run II) and represent an integrated luminosity of 1 fb{sup -1}. The experimental measurement of W production charge asymmetry is compared to higher order QCD predictions generated using MRST2006 and CTEQ6 parton distribution functi… more
Date: May 1, 2008
Creator: Han, Bo-Young
Partner: UNT Libraries Government Documents Department
open access

The Component-Based Application for GAMESS

Description: GAMESS, a quantum chetnistry program for electronic structure calculations, has been freely shared by high-performance application scientists for over twenty years. It provides a rich set of functionalities and can be run on a variety of parallel platforms through a distributed data interface. While a chemistry computation is sophisticated and hard to develop, the resource sharing among different chemistry packages will accelerate the development of new computations and encourage the cooperatio… more
Date: May 1, 2008
Creator: Peng, Fang
Partner: UNT Libraries Government Documents Department
open access

Role of Nucleation and Growth in Two-Phase Microstructure Formation

Description: During the directional solidification of peritectic alloys, a rich variety of two-phase microstructures develop, and the selection process of a specific microstructure is complicated due to the following two considerations. (1) In contrast to many single phase and eutectic microstructures that grow under steady state conditions, two-phase microstructures in a peritectic system often evolve under non-steady-state conditions that can lead to oscillatory microstructures, and (2) the microstructure… more
Date: May 1, 2008
Creator: Shin, Jong Ho
Partner: UNT Libraries Government Documents Department
open access

Hadronic Production of psi(2S) Cross section and Polarization

Description: The hadronic production cross section and the polarization of {psi}(2S) meson are measured by using the data from p{bar p} collisions at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The datasets used correspond to integrated luminosity of 1.1 fb{sup -1} and 800 pb{sup -1}, respectively. The decay {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} is used to reconstruct {psi}(2S) mesons in the rapidity range |y({psi}(2S))| < 0.6. The coverage of the p{sub T} range is 2.0 GeV/c… more
Date: May 1, 2008
Creator: Chung, Kwangzoo
Partner: UNT Libraries Government Documents Department
open access

Top quark pair production cross section in the lepton+jets channel using b-tagging at D0

Description: The top quark pair production cross section measurement in the lepton+jets channel with b-tagging algorithm is described. About 900 pb{sup -1} data collected by the D0 detector at the Fermilab Tevatron are used for this analysis. In this thesis, event selection, background estimation, and cross section calculation are discussed in detail. In addition, calibration of the Luminosity Monitor readout electronics and a new b-tagging algorithm, the SLTNN tagger, are also discussed in this thesis.
Date: May 1, 2008
Creator: Yoo, H.D. & U., /Brown
Partner: UNT Libraries Government Documents Department
open access

A Measurement of the t anti-t Production Cross Section in p anti-p Collisions at s**(1/2) = 1.96-TeV using Soft Muon Tagging

Description: I present a measurement of the t{bar t} production cross section at {radical}s = 1.96 TeV using 2034 pb{sup -1} of CDF Run II data using events with a high transverse momentum electron or muon, three or more jets, and missing transverse energy. The measurement assumes a t {yields} Wb branching fraction of 100 percent. Events consistent with t{bar t} decay are found by identifying jets containing heavy-flavor semileptonic decays to muons. The dominant backgrounds are evaluated directly from the … more
Date: May 1, 2008
Creator: Grundler, Ulysses A.
Partner: UNT Libraries Government Documents Department
open access

Search for pair production of scalar top quarks decaying to a tau lepton and a b quark in 1.96 TeV ppbar collisions

Description: I present the results of a search for pair production of scalar top quarks ({tilde t}{sub 1}) in an R-parity violating supersymmetric scenario using 322 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected by the upgraded Collider Detector at Fermilab. I assume each {tilde t}{sub 1} decays into a {tau} lepton and a b quark, with branching ratio {beta}, and search for final states containing either an electron or a muon from a leptonic {tau} decay, a hadronically decaying {tau} l… more
Date: May 1, 2008
Creator: Khotilovich, Vadim, G. & A-M, /Texas
Partner: UNT Libraries Government Documents Department
open access

Laser desorption/ionization mass spectrometry for direct profiling and imaging of small molecules from raw biological materials

Description: Matrix-assisted laser desorption/ionization(MALDI) mass spectrometry(MS) has been widely used for analysis of biological molecules, especially macromolecules such as proteins. However, MALDI MS has a problem in small molecule (less than 1 kDa) analysis because of the signal saturation by organic matrixes in the low mass region. In imaging MS (IMS), inhomogeneous surface formation due to the co-crystallization process by organic MALDI matrixes limits the spatial resolution of the mass spectral i… more
Date: May 15, 2008
Creator: Cha, Sangwon
Partner: UNT Libraries Government Documents Department
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