This dissertation presents the research on the development of mesoporous silica based nanotechnology for applications in biofuels and plant science. Mesoporous silica nanoparticles (MSNs) have been the subject of great interest in the last two decades due to their unique properties of high surface area, tunable pore size and particle morphology. The robust nature of the silica framework is easily functionalized to make the MSNs a promising option for selective separations. Also, the independent channels that form the pores of MSN have been exploited in the use of particles as platforms for molecular delivery. Pore size and organic functionality are varied to identify the ideal adsorbent material for free fatty acids (FFAs). The resulting material is able to sequester FFAs with a high degree of selectivity from a simulated solution and microalgal oil. The recyclability and industrial implications are also explored. A continuation of the previous material, further tuning of MSN pore size was investigated. Particles with a smaller diameter selectively sequester polyunsaturated free fatty acids (PUFAs) over monounsaturated FFAs and saturated FFAs. The experimental results were verified with molecular modeling. Mesoporous silica nanoparticle materials with a pore diameter of 10 nm (MSN-10) were decorated with small gold nanoparticles. The …

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A process for the deposition of yttria stabilized zirconia (YSZ) films, on porous substrates, has been developed. These films have possible applications as electrolyte membranes in fuel cells. The films were deposited from colloidal suspensions through the vacuum infiltration technique. Films were deposited on both fully sintered and partially sintered substrates. A critical cracking thickness for the films was identified and strategies are presented to overcome this barrier. Green film density was also examined, and a method for improving green density by changing suspension pH and surfactant was developed. A dependence of film density on film thickness was observed, and materials interactions are suggested as a possible cause. Non-shorted YSZ films were obtained on co-fired substrates, and a cathode supported solid oxide fuel cell was constructed and characterized.

Many problems of physical interest have solutions which are generally quite smooth in a large portion of the region of interest, but have local phenomena such as shocks, discontinuities or large gradients which require much more accurate approximations or finer grids for reasonable accuracy. Examples are atmospheric fronts, ocean currents, and geological discontinuities. In this thesis we develop and partially analyze an adaptive finite difference mesh refinement algorithm for the initial boundary value problem for hyperbolic systems in one space dimension. The method uses clusters of uniform grids which can ''move'' along with pulses or steep gradients appearing in the calculation, and which are superimposed over a uniform coarse grid. Such refinements are created, destroyed, merged, separated, recursively nested or moved based on estimates of the local truncation error. We use a four-way linked tree and sequentially allocated deques (double-ended queues) to perform these operations efficiently. The local truncation error in the interior of the region is estimated using a three-step Richardson extrapolation procedure, which can also be considered a deferred correction method. At the boundaries we employ differences to estimate the error. Our algorithm was implemented using a portable, extensible Fortran preprocessor, to which we added records and pointers. …

We present results on a search for a heavy charged vector boson, W', decaying to an electron-neutrino pair in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample corresponding to an integrated luminosity of 205 pb{sup -1}. We found no evidence of this decay channel, and set 95% confidence level limits on the production cross section times branching fraction assuming the light neutrino. We also set the limit on the W' boson mass at M{sub W'} > 788 GeV/c{sup 2}, assuming the standard model strength couplings.

This thesis presents evidence for the B**{sup 0} and {Sigma}{sub b}{sup (*){+-}} hadrons in proton-antiproton collisions at a center of mass energy of 1.96 TeV, using data collected by the Collider Detector at Fermilab. In the search for B**{sup 0} {yields} B{sup {+-}} {pi}{sup {-+}}, two B{sup {+-}} decays modes are reconstructed: B{sup {+-}} {yields} J/{Upsilon}K{sup {+-}}, where J/{Upsilon} {yields} {mu}{sup +}{mu}{sup -}, and B{sup {+-}} {yields} {bar D}{sup 0}{pi}{sup {+-}}, where {bar D}{sup 0} {yields} K{sup {+-}} {pi}{sup {+-}}. Both modes are reconstructed using 370 {+-} 20 pb{sup -1} of data. Combining the B{sup {+-}} meson with a charged pion to reconstruct B**{sup 0} led to the observation and measurement of the masses of the two narrow B**{sup 0} states, B{sub 1}{sup 0} and B*{sub 2}{sup 0}, of m(B{sub 1}{sup 0}) = 5734 {+-} 3(stat.) {+-} 2(syst.) MeV/c{sup 2}; m(B*{sub 2}{sup 0}) = 5738 {+-} 5(stat.) {+-} 1(syst.) MeV/c{sup 2}. In the search for {Sigma}{sub b}{sup (*){+-}} {yields} {Lambda}{sub b}{sup 0}{pi}{sup {+-}}, the {Lambda}{sub b}{sup 0} is reconstructed in the decay mode {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}, where {Lambda}{sub c}{sup +} {yields} pK{sup -} {pi}{sup +}, using 1070 {+-} 60 pb{sup -1} of data. Upon combining …

MINOS is a long-baseline neutrino oscillations experiment located at Fermi National Accelerator Laboratory (FNAL), USA. It makes use of the NuMI neutrino beamline and two functionally identical detectors located at distances of {approx}1km and {approx}735km from the neutrino production target respectively. The Near Detector measures the composition and energy spectrum of the neutrino beam with high precision while the Far Detector looks for evidence of neutrino oscillations. This thesis presents work conducted in two distinct areas of the MINOS experiment: analysis of neutral current and charged current interactions. While charged current events are only sensitive to muon neutrino disappearance, neutral current events can be used to distinguish oscillations into sterile neutrinos from those involving only active neutrino species. A complete, preliminary neutral current study is performed on simulated data. This is followed by a more detailed investigation of neutral current neutrino interactions in the MINOS Near Detector. A procedure identifying neutral current interactions and rejecting backgrounds due to reconstruction failures is developed. Two distinct event classification methods are investigated. The selected neutral current events in the Near Detector are used to extract corrections to the neutral current cross-section in the MINOS Monte Carlo simulation as a function of energy. The …

I have performed a search for t-channel single top quark production in p{bar p} collisions at 1.96 TeV on a 366 pb{sup -1} dataset collected with the D0 detector from 2002-2005. The analysis is restricted to the leptonic decay of the W boson from the top quark to an electron or muon, tq{bar b} {yields} lv{sub l}b q{bar b} (l = e,{mu}). A powerful b-quark tagging algorithm derived from neural networks is used to identify b jets and significantly reduce background. I further use neural networks to discriminate signal from background, and apply a binned likelihood calculation to the neural network output distributions to derive the final limits. No direct observation of single top quark production has been made, and I report expected/measured 95% confidence level limits of 3.5/8.0 pb.

The work presented in this thesis is mainly focused on the application in a {Delta}m{sub s} measurement. Chapter 1 starts with a general theoretical introduction on the unitarity triangle with a focus on the impact of a {Delta}m{sub s} measurement. Chapter 2 then describes the experimental setup, consisting of the Tevatron collider and the CDF II detector, that was used to collect the data. In chapter 3 the concept of parameter estimation using binned and unbinned maximum likelihood fits is laid out. In addition an introduction to the NeuroBayes{reg_sign} neural network package is given. Chapter 4 outlines the analysis steps walking the path from the trigger level selection to fully reconstructed B mesons candidates. In chapter 5 the concepts and formulas that form the ingredients to an unbinned maximum likelihood fit of {Delta}m{sub s} ({Delta}m{sub d}) from a sample of reconstructed B mesons are discussed. Chapter 6 then introduces the novel method of using neural networks to achieve an improved signal selection. First the method is developed, tested and validated using the decay B{sup 0} {yields} D{pi}, D {yields} K{pi}{pi} and then applied to the kinematically very similar decay B{sub s} {yields} D{sub s}{pi}, D{sub s} {yields} {phi}{pi}, {phi} {yields} …

At a hadron collider, diphoton (γγ) production allows detailed studies of the Standard Model (SM), as well as as searches for new phenomena, such as new heavy resonances, extra spatial dimensions or cascade decays of heavy new particles. Within the SM, continuum γγ+X production is characterized by a steeply-falling γγ mass spectrum, on top of which a heavy resonance decaying into γγ can potentially be observed. In particular, this is considered one of the most promising discovery channels for a SM Higgs boson at the LHC, despite the small branching ratio of BR (H → γγ) {approx} 0.2% for 110 < M_Higgs < 140 GeV. At the Tevatron, the dominant SM Higgs boson production mechanism is gluon fusion, followed by associated production with a W or Z boson, and vector boson fusion. While the SM Higgs production rate at the Tevatron is not sufficient to observe it in the γγ mode, the Hgg and Hγγ couplings, being loop-mediated, are particularly sensitive to new physics effects. Furthermore, in some models beyond the SM, for instance, fermiophobic Higgs, with no couplings to fermions, the BR (H → γγ) can be enhanced significantly relative to the SM prediction, while has the SM-like production …

This dissertation describes a measurement of the forward-backward asymmetry(A_FB) in p$\bar{p}$ → Z/γ* → ee events using 5.0 fb^-1 data collected by the D0 detector at the Fermilab Tevatron. The AFB is measured as a function of the invariant mass of the electron-positron pair. Along with obtaining normalized differential cross section 1/σ x dσ/dM and Z to light quark couplings, we measured the Standard Model(SM) fundamental parameter, the effective weak mixing angle sin² θ$lept\atop{eff}$, with an unprecedented precise in light quark sector, namely the single D0 measurement has surpassed the LEP combination of four experiment results of inclusive hadronic charge asymmetry.

The top quark has been discovered by CDF and D0 experiments in 1995 at the proton-antiproton collider Tevatron. The amount of data recorded by both experiments makes it possible to accurately study the properties of this quark: its mass is now known to better than 1% accuracy. This thesis describes the measurement of the top pair cross section in the electron muon channel with 4, 3 fb^-1 recorded data between 2006 and 2009 by the D0 experiment. Since the final state included a muon, improvements of some aspects of its identification have been performed : a study of the contamination of the cosmic muons and a study of the quality of the muon tracks. The cross section measurement is in good agreement with the theoretical calculations and the other experimental measurements. This measurement has been used to extract a value for the top quark mass. This method allows for the extraction of a better defined top mass than direct measurements as it depends less on Monte Carlo simulations. The uncertainty on this extracted mass, dominated by the experimental one, is however larger than for direct measurements. In order to decrease this uncertainty, the ratio of the Z boson and …

Understanding the universe, its birth and its future is one of the biggest motivations in physics. In order to understand the cosmos, the fundamental particles forming the universe, the components our matter is built of need to be known and understood. Over time physicists have built a theory which describes the physics of the known fundamental particles very well: the Standard Model (SM) of particle physics. The SM describes the particles, their interactions and phenomena with high precision. So far no proven deviations from the SM have been found, though recently evidence for possible physics beyond the SM has been observed. The SM is not describing the mass of the elementary particles however and even with the addition of the Higgs mechanism giving mass to the particles, we have no full theory for all four fundamental forces. We know the model needs to be extended or replaced by another one, as gravitation is not included in the SM. Having a theory which describes all fundamental particles found so far and all but one fundamental interaction is a great success. However, all this describes about 4% of the universe we live in. 23% is dark matter and 73% is dark energy. …

The development of Superconducting QUantum Interference Device (SQUID)-based magnetometer for two applications, in vivo prepolarized, ultra-low field MRI of humans and dispersive readout of SQUIDs for micro- and nano-scale magnetometery, are the focus of this thesis.

The MINOS experiment is a long-baseline neutrino oscillation experiment which sends a high intensity muon neutrino beam through two functionally identical detectors, a Near detector at the Fermi National Accelerator Laboratory in Illinois, 1km from the beam source, and a Far detector, 734km away, in the Soudan Mine in Minnesota. MINOS may be able to measure the neutrino mixing angle parameter sin{sup 2} 2{theta}{sub 13} for the first time. Detector granularity, however, makes it very hard to distinguish any {nu}{sub e} appearance signal events characteristic of a non-zero value of {theta}{sub 13} from background neutral current (NC) and short-track {nu}{sub {mu}} charged current (CC) events. Also, uncertainties in the hadronic shower modeling in the kinematic region characteristic of this analysis are relatively large. A new data-driven background decomposition method designed to address those issues is developed and its results presented. By removing the long muon tracks from {nu}{sub {mu}}-CC events, the Muon Removed Charge Current (MRCC) method creates independent pseudo-NC samples that can be used to correct the MINOS Monte Carlo to agree with the high-statistics Near detector data and to decompose the latter into components so as to predict the expected Far detector background. The MRCC method also provides …

In this dissertation, we present the results of a time-dependent angular analysis of B_s → J/ΨΦ decays performed with the use of initial-state flavor tagging. CP violation is observed in this mode through the interference of decay without net mixing and decay with net mixing, that is, B_s → J/ΨΦ and B_s → $\bar{B}$_s → J/ΨΦ . The time-dependent angular analysis is used to extract the decay widths of the heavy and light B_s eigenstates and the difference between these decay widths ΔΓ_s {triple_bond} Γ_s^L-Γ_s^H. Initial-state flavor tagging is used to determine the matter-antimatter content of the B_s mesons at production time. We combine flavor tagging with the angular analysis, which statistically determines the contributions of the CP-even and CP-odd components at decay time, to measure the CP-violating phase β_s. The phase β_s is expressed in terms of elements of the Cabibbo-Kobayashi-Maskawa matrix as β_s {triple_bond} arg (-V_tsV*_tb/V_csV*_cb), and is predicted by the Standard Model to be close to zero, β_s^SM = 0.02. In the measurement of ΔΓ_s, we use a dataset corresponding to 1.7 fb^-1 of luminosity, collected at the CDF experiment from proton-antiproton collisions at a center of mass energy √s = 1.96 TeV. In the measurement of …

High Pressure Scanning Tunneling Microscopy (HP-STM) and Ambient Pressure X-ray Photoelectron Spectroscopy were used to study the structural properties and catalytic behavior of noble metal surfaces at high pressure. HP-STM was used to study the structural rearrangement of the top most atomic surface layer of the metal surfaces in response to changes in gas pressure and reactive conditions. AP-XPS was applied to single crystal and nanoparticle systems to monitor changes in the chemical composition of the surface layer in response to changing gas conditions. STM studies on the Pt(100) crystal face showed the lifting of the Pt(100)-hex surface reconstruction in the presence of CO, H₂, and Benzene. The gas adsorption and subsequent charge transfer relieves the surface strain caused by the low coordination number of the (100) surface atoms allowing the formation of a (1 x 1) surface structure commensurate with the bulk terminated crystal structure. The surface phase change causes a transformation of the surface layer from hexagonal packing geometry to a four-fold symmetric surface which is rich in atomic defects. Lifting the hex reconstruction at room temperature resulted in a surface structure decorated with 2-3 nm Pt adatom islands with a high density of step edge sites. Annealing …

This paper contains a detailed interpretation of E-field ratio telluric, bipole-dipole resistivity mapping, and dipole-dipole resistivity data obtained in the course of geophysical exploration of the Leach Hot Springs area of Grass Valley, Nevada. Several areas are singled out as being worthy of further investigation of their geothermal potential. Comparison of the three electrical exploration techniques indicates that: the bipole-dipole resistivity mapping method is the least useful; the dipole-dipole resistivity method can be very useful, but is, for practical purposes, exceptionally expensive and difficult to interpret; the E-field ratio telluric method can be a highly successful reconnaissance technique for delineating structures and relating the resistivities of different regions within the survey area.

This thesis describes the measurement of the inclusive three-jet cross section in proton-antiproton collisions at √s = 1.96 TeV measured at the D0 experiment at the Fermilab Tevatron Collider in the Fermi National Accelerator Laboratory, Batavia, Illinois, USA. The cross section as a function of three-jet invariant mass is provided in three regions of the third jet transverse momentum and three regions of jet rapidities. It utilizes a data sample collected in the so called Run IIa data taking period (2002-2006) corresponding to the integrated luminosity of about 0.7 fb^-1. The results are used to test the next-to-leading order predictions of Quantum chromodynamics computed using the latest parton distribution functions.

An atomic-beam magnetic-resonance apparatus operating on the flop-in principle was used to measure the nuclear spins and hyperfine-structure separations of the /sup 2/S/sub 1/2, electronic ground state for several radioactive isotopes of silver and gold. The results of these experiments, together with calculated values of the nuclear magnetic-dipole moments, are given (auth)

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This paper is a two-dimensional numerical model study and comparison of the polar dipole-dipole and Schlumberger resistivity arrays. A catalog of dipole-dipole and Schlumberger apparent resistivity pseudo-sections is presented. It is concluded that: for the Schlumberger array, data can be accurately interpreted only if the resistivity structure is horizontally layered, and conductive bodies having a depth of burial greater than their width are not observed; for the dipole-dipole array, complex anomaly patterns unrelated in appearance to the causative structure result from simple models, hence, a familiarity with model results is essential to interpretation of these data.