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Biomolecular Assembly of Gold Nanocrystals

Description: Over the past ten years, methods have been developed to construct discrete nanostructures using nanocrystals and biomolecules. While these frequently consist of gold nanocrystals and DNA, semiconductor nanocrystals as well as antibodies and enzymes have also been used. One example of discrete nanostructures is dimers of gold nanocrystals linked together with complementary DNA. This type of nanostructure is also known as a nanocrystal molecule. Discrete nanostructures of this kind have a number … more
Date: May 20, 2005
Creator: Micheel, Christine Marya
Partner: UNT Libraries Government Documents Department
open access

Search for the Higgs Boson Using High-pT Isolated Like-Sign Dil Events in 1.96-TeV Proton-Antiproton Collisions

Description: Our physics objective is to search for the neutral on using events containing a like-sign dilepton pair in the following reaction: q{bar q} {yields} W{sup {+-}} H {yields} W{sup {+-}} W*W* {yields} {ell}{sup {+-}}{ell}{sup {+-}} + X. The relevant Higgs boson mass region is above 160 GeV/c{sup 2} for the Standard Model Higgs boson where the branching fraction of H {yields} W*W* supersedes that of H {yields} b{bar b}. The search for this signature in the region at low mass (less than 135 GeV/c{su… more
Date: March 1, 2005
Creator: Kobayashi, Hirokazu
Partner: UNT Libraries Government Documents Department
open access

Search for quark-lepton compositeness in the dimuon final state at D0

Description: We used the upgraded D0 detector at the Tevatron at {radical}s = 1.96 TeV to collect data in a search for a compositeness signature of quarks and leptons. This analysis uses an integrated luminosity of 400 pb{sup -1}. The high-mass dimuon mass spectrum is compared with that predicted by Drell-Yan (DY) scattering, modified by a contact interaction. This interaction is parameterized by a compositeness energy scale factor {Lambda}. Preliminary limits on {lambda} are set at the 95% confidence level… more
Date: January 1, 2005
Creator: Xuan, Nguyen Phuoc & U., /Notre Dame
Partner: UNT Libraries Government Documents Department
open access

Systematic Comparison of the MINOS Near and Far Detector Readout Systems

Description: The MINOS experiment is a neutrino oscillation baseline experiment intending to use high resolution L/E neutrinos to measure the atmospheric neutrino oscillations parameters to unprecedented precision. Two detectors have been built to realize the measurements, a Near detector, located about 1km downstream from the beam target at the Fermi Laboratory, and a Far detector, located at 736km, at the Soudan Laboratory. The technique relies on the Near detector to measure the un-oscillated neutrino sp… more
Date: May 1, 2005
Creator: Cabrera, Anatael
Partner: UNT Libraries Government Documents Department
open access

CDF Grid computing and the decay X(3872) ---> J/psi pi+ pi- with J/psi ---> e+ e-

Description: The main aim of physics research is to obtain a consistent description of nature leading to a detailed understanding of the phenomena observed in experiments. The field of particle physics focuses on the discovery and understanding of the fundamental particles and the forces by which they interact with each other. Using methods from group theory, the present knowledge can be mathematically described by the so-called ''Standard Model'', which interprets the fundamental particles (quarks and lept… more
Date: November 1, 2005
Creator: Kerzel, Ulrich
Partner: UNT Libraries Government Documents Department
open access

Measurement of single spin asymmetry and fifth structure function for the proton(electron vec, electron Kaon+)Lambda reaction with CEBAF Large Acceptance Spectrometer (CLAS)

Description: The single spin asymmetry, A{sub LT} ?, and the polarized structure function, ?{sub LT}?, for the p(e,e?K{sup +})? reaction in the resonance region have been measured and extracted using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were taken at an electron beam energy of 2.567 GeV. The large acceptance of CLAS allows for full azimuthal angle coverage over a large range of center-of-mass scattering angles. Results were obtained that span a range in Q{sup 2} from 0.5 to … more
Date: August 31, 2005
Creator: Nasseripour, Rahksha
Partner: UNT Libraries Government Documents Department
open access

Preliminary Measurement of Neutrino Oscillation Parameters By NuMI/MINOS and Calibration Studies for Improving this Measurement

Description: This thesis explains the origins of neutrinos and their interactions, and the phenomenon of neutrino oscillations. Experiments for measuring neutrino oscillations are mentioned and the experiment investigated in this thesis, the ''Main Injector Neutrino Oscillation Search'', and its neutrino beam, the Fermi National Accelerator Laboratory's ''Neutrinos At The Main Injector'', are described. MINOS is a long baseline (735 km) neutrino oscillation experiment with a near and a far detector, intende… more
Date: November 1, 2005
Creator: Symes, Philip Andrew & U., /Sussex
Partner: UNT Libraries Government Documents Department
open access

Measurement of z0 gamma production in ppbar collisions at s**(1/2) = 1.96 TeV

Description: The cross-section of p{bar p} {yields} Z{sup 0}{gamma} + X production at {radical}s = 1.96 TeV using the CDF II detector at the Fermilab Tevatron is measured using 202 pb{sup -1} of data from March 2002 to September 2003, collected with high P{sub T} lepton triggers. The number of events observed and their kinematic distributions are compared to the NLO Standard Model prediction in both the Z{sup 0} {yields} e{sup +}e{sup -} and Z{sup 0} {yields} {mu}{sup +}{mu}{sup -} channels. For a minimum l… more
Date: March 1, 2005
Creator: Hayward, Helen Sarah
Partner: UNT Libraries Government Documents Department
open access

Search for neutrino oscillations in the MINOS experiment by using quasi-elastic interactions

Description: The enthusiasm of the scientific community for studying oscillations of neutrinos is equaled only by the mass of their detectors. The MINOS experiment determines and compares the near spectrum of muonic neutrinos from the NUMI beam to the far one, in order to measure two oscillation parameters: {Delta}m{sub 23}{sup 2} and sin{sup 2} (2{theta}{sub 23}). The spectra are obtained by analyzing the charged current interactions which difficulty lies in identifying the interactions products (e.g. muon… more
Date: September 1, 2005
Creator: Piteira, Rodolphe
Partner: UNT Libraries Government Documents Department
open access

A neural jet charge tagger for the measurement of the B/s0 anti-B/s0 oscillation frequency at CDF

Description: A Jet Charge Tagger algorithm for b-flavour tagging for the measurement of {Delta}m{sub s} at CDF has been presented. The tagger is based on a b-track probability variable and a b-jet probability variable, both obtained by combining the information available in b{bar b} events with a Neural Network. The tagging power measured on data is 0.917 {+-} 0.031% e+SVT sample; 0.938 {+-} 0.029% {mu}+SVT sample which is {approx}30% larger than the cut based Jet Charge Tagger employed for the B{sub s}{sup… more
Date: July 1, 2005
Creator: Lecci, Claudia
Partner: UNT Libraries Government Documents Department
open access

Cosmic ray muon charge ratio in the MINOS far detector

Description: The MINOS Far Detector is a 5.4 kiloton (5.2 kt steel plus 0.2 kt scintillator plus aluminum skin) magnetized tracking calorimeter located 710 meters underground in the Soudan mine in Northern Minnesota. MINOS is the first large, deep underground detector with a magnetic field and thus capable of making measurements of the momentum and charge of cosmic ray muons. Despite encountering unexpected anomalies in distributions of the charge ratio (N{sub {mu}{sup +}}/N{sub {mu}{sup -}}) of cosmic muon… more
Date: December 1, 2005
Creator: Beall, Erik B
Partner: UNT Libraries Government Documents Department
open access

Ion Deflection for Final Optics in Laser Inertial Fusion Power Plants

Description: Left unprotected, both transmissive and reflective final optics in a laser-driven inertial fusion power plant would quickly fail from melting, pulsed thermal stress, or degradation of optical properties as a result of ion implantation. One potential option for mitigating this threat is to magnetically deflect the ions such that they are directed to a robust energy dump. In this paper we detail integrated studies that have been carried out to assess the viability of this approach for protecting … more
Date: December 12, 2005
Creator: Abbott, R P
Partner: UNT Libraries Government Documents Department
open access

Synthesis, Structure, and Reactivity ofbis(1,2,4-tri-t-butylcyclopentadienyl) Complexes of Cerium

Description: The sterically demanding 1,2,4-tri-t-butylcyclopentadienylligand (1,2,4-(Me3C)3C5H2, hereafter Cp') has been used to preparemonomeric cerium metallocenes, Cp 2CeX (X = Cl, I, OSO2CF3), which areused to synthesize the benzyl, Cp'2CeCH2C6H5. The benzyl is a usefulstarting material for preparing other complexes in the Cp'2CeZ system (Z= BF4, F, NH2, C6H5, H). X-ray crystal structures of Cp'2CeOSO2CF3,Cp'2CeF, Cp'2CeCH2C6H5, and Cp'2CeH are presented. The benzyl slowlydecomposes in solution to tolu… more
Date: May 19, 2005
Creator: Werkema, Evan L.
Partner: UNT Libraries Government Documents Department
open access

Preparation, crystallography, magnetic and magnetothermal properties of Ce5SiGe4-x alloys

Description: An investigation of the crystal structure and the phase relationships in the Ce{sub 5}Si{sub 4-x}Ge{sub x} system has been carried out. The crystal structures of the single phase intermetallics were characterized using X-ray powder diffraction and subsequent refinement employing the Rietveld analysis technique was performed. The intermetallic system was found to crystallize in three distinct crystal structures. The Ce{sub 5}Si{sub 4}-based solid solution extends from x = 0 to x = 2.15 and it wa… more
Date: May 1, 2005
Creator: Vijayaraghavan, Rangarajan
Partner: UNT Libraries Government Documents Department
open access

Synthesis and application of new polymer bound catalysts

Description: Nitric acid has been shown to be a weak acid in acetonitrile. It is conceivable that a nitrate salt of a weakly Lewis acidic cation could furnish a ''naked'' nitrate anion as a basic catalyst in a variety of reactions in non-aqueous solvents. Such a nitrate salt could also be bound to a polymeric support via the cation, thereby allowing for reclamation and recycling of the nitrate ion. This subject is dealt with in Chapter 2, wherein my contributions consisted of performing all the reactions wi… more
Date: August 1, 2005
Creator: Fetterly, Brandon Michael
Partner: UNT Libraries Government Documents Department
open access

An Analytic Tool to Investigate the Effect of Binder on the Sensitivity of HMX-Based Plastic Bonded Explosives in the Skid Test

Description: This project will develop an analytical tool to calculate performance of HMX based PBXs in the skid test. The skid-test is used as a means to measure sensitivity for large charges in handling situations. Each series of skid tests requires dozens of drops of large billets. It is proposed that the reaction (or lack of one) of PBXs in the skid test is governed by the mechanical properties of the binder. If true, one might be able to develop an analytical tool to estimate skid test behavior for new… more
Date: February 1, 2005
Creator: Hayden, D. W.
Partner: UNT Libraries Government Documents Department
open access

I. Excluded Volume Effects in Ising Cluster Distributions and Nuclear Multifragmentation II. Multiple-Chance Effects in Alpha-Particle Evaporation

Description: In Part 1, geometric clusters of the Ising model are studied as possible model clusters for nuclear multifragmentation. These clusters may not be considered as non-interacting (ideal gas) due to excluded volume effect which predominantly is the artifact of the cluster's finite size. Interaction significantly complicates the use of clusters in the analysis of thermodynamic systems. Stillinger's theory is used as a basis for the analysis, which within the RFL (Reiss, Frisch, Lebowitz) fluid-of-sp… more
Date: May 16, 2005
Creator: Breus, Dimitry E.
Partner: UNT Libraries Government Documents Department
open access

Microstructual investigation of mixed rar earth iron boron processed vis melt-spinning and high-pressure gas-atomization for isotrophic bonded permanent magnets

Description: A solid solution of three rare earths (RE) in the RE{sub 2}Fe{sub 14}B structure have been combined to create the novel mixed rare earth iron boron (MRE{sub 2}Fe{sub 14}B) alloy family. MRE{sub 2}Fe{sub 14}B exhibits reduced temperature dependent magnetic properties; remanence and coercivity. The desired form of MRE{sub 2}Fe{sub 14}B is a powder that can be blended with a polymer binder and compression or injection molded to form an isotropic polymer bonded permanent magnet (PBM). Commercially,… more
Date: August 1, 2005
Creator: Buelow, Nicholas Lee
Partner: UNT Libraries Government Documents Department
open access

A Performance Comparison of Tree and Ring Topologies in Distributed System

Description: A distributed system is a collection of computers that are connected via a communication network. Distributed systems have become commonplace due to the wide availability of low-cost, high performance computers and network devices. However, the management infrastructure often does not scale well when distributed systems get very large. Some of the considerations in building a distributed system are the choice of the network topology and the method used to construct the distributed system so as … more
Date: December 19, 2005
Creator: Huang, Min
Partner: UNT Libraries Government Documents Department
open access

Probing Properties of Glassy Water and Other Liquids with Site Selective Spectroscopies

Description: The standard non-photochemical hole burning (NPHB) mechanism, which involves phonon-assisted tunneling in the electronically excited state, was originally proposed to explain the light-induced frequency change of chemically stable molecules in glassy solids at liquid helium temperatures by this research group more than two decades ago. The NPHB mechanism was then further elucidated and the concept of intrinsic to glass configurational relaxation processes as pre-mediating step to the hole burni… more
Date: August 12, 2005
Creator: Dang, Nhan Chuong
Partner: UNT Libraries Government Documents Department
open access

Effects of Various Blowout Panel Configurations on the Structural Response of LANL Building 16-340 to Internal Explosions1

Description: The risk of accidental detonation is present whenever any type of high explosives processing activity is performed. These activities are typically carried out indoors to protect processing equipment from the weather and to hide possibly secret processes from view. Often, highly strengthened reinforced concrete buildings are employed to house these activities. These buildings may incorporate several design features, including the use of lightweight frangible blowout panels, to help mitigate blas… more
Date: September 30, 2005
Creator: Wilke, Jason P.
Partner: UNT Libraries Government Documents Department
open access

Theory for dynamical self arrest and gelation in microemulsions and the block copolymer systems

Description: The main purpose of this work is to investigate the glassy behavior of microemulsions and block copolymers. The origin of glassy behavior in microemulsions and block copolymers is frustration due to a competition between short-range interaction and long range interaction. According to the charge frustrated Ising model, the competition between ferromagnetic interaction and antiferromagnetic interaction is the origin of frustration in microemulsions. The competition between entropic effects and s… more
Date: May 1, 2005
Creator: Wu, Sangwook
Partner: UNT Libraries Government Documents Department
open access

Controlled Electron Injection into Plasma Accelerators and SpaceCharge Estimates

Description: Plasma based accelerators are capable of producing electron sources which are ultra-compact (a few microns) and high energies (up to hundreds of MeVs) in much shorter distances than conventional accelerators. This is due to the large longitudinal electric field that can be excited without the limitation of breakdown as in RF structures.The characteristic scale length of the accelerating field is the plasma wavelength and for typical densities ranging from 1018 - 1019 cm-3, the accelerating fiel… more
Date: September 1, 2005
Creator: Fubiani, Gwenael J.
Partner: UNT Libraries Government Documents Department
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