The development of a neural network based electron finder designed for the ZEUS calorimeter is described. A study of elastic and inelastic J/ψ meson production in electron-proton collisions at HERA using the ZEUS detector is presented. During the 1993 and 1994 running periods, the ZEUS detector collected ~ 500 nb^-1 and ~ 3 pb^-1 of data respectively. The direct inelastic J/ψ photoproduction cross-section is measured for both running periods and an attempt is made to extract the gluon density inside the proton using the 1994 inelastic J/ψ sample.

This thesis is a study of solid halogenated organic compounds by Nuclear Magnetic Resonance Spectroscopy (NMR) in an attempt to extract previously inaccessible information. The first part of the thesis is concerned with three fluorinated steroids, studied by observing (^1)H, (^13)C and (^19)F nuclei. A number of experimental techniques are employed to verify solution-state and solid-state spectral assignments, and spectral anomalies are discussed. Both proton-coupled and proton-decoupled (^19)F solid-state spectra, recorded using specially designed spectrometer hardware, are presented. The huge gain in resolution afforded by the implementation of proton decoupling allows static and MAS spectra to yield previously inaccessible information pertaining to various NMR parameters of the fluorine nuclei. Advantages of (^1)H→(^19)F cross-polarisation experiments over single-pulse experiments are explained and rotational resonance, dipolar dephasing, T(_1), measurement and spin-exchange experiments are presented from which information regarding phenomena such as spin diffusion and polymorphism is gleaned. The second part of the thesis focusses on the topic of residual dipolar coupling, the transfer of quadrupolar effects to spin-1/2 nuclei via dipolar coupling and/or anisotropy m indhect coupling. Unexpected, field-dependent, multiplicities for signals in spectra of spin-1/2 nuclei are observed, which can be used to evaluate certain fundamental NMR parameters including the quadrupolar coupling constant and, m favourable cases, anisotropy in indirect coupling. The phenomenon is comprehensively studied for the (^13)C, (^35,37)Cl and (^13)C, (^79,81)Br spin-pairs in a range of solid halogenated compounds. Coupling to more than one halogen nucleus and long- range (non-bonded) coupling are considered. First-order perturbation, inverse first- order and "exact" theories, that allow the multiplet line positions to be predicted, are introduced and their results are subsequently compared to the experimentally observed the positions. Rapid molecular motion is shown to negate the effects of residual dipolar coupling and the phenomenon is analysed with the aid of NQR measurements.

Fragmentation is the process by which bare quarks dress themselves up as hadrons. Since we cannot get reliable calculations of this process using perturbative quantum chromodynamics, the fragmentation properties of quarks must be obtained empirically. We report on the signal extraction and relative transverse momentum (pT) spectrum determination that will lead to a high precision measurement of relative fragmentation fractions of b quarks into B hadrons, in 1.96 TeV pp¯ collisions. Using 1.9 fb-1 of data taken with the CDF-II detector, we fully reconstruct 473 +/- 42 B0s→D-sp + , 15206 +/- 203 B0 → D-pi+, 1483 +/- 45 B0 → D*-pi + and 4444 +/- 297 L0b→L+ cp- candidate decays. In order to reduce systematic uncertainties, ratios of pT spectra are reported. We find that Bs and B0 mesons are produced with similar pT and Λb baryons are produced with lower pT than B0 mesons. Our results are consistent with previous CDF measurements suggesting a difference between fragmentation processes observed at lepton and hadron colliders.

No description available.

N-methyl-6-hydroxyquinolinium (NM6HQ) is a powerful excited-state proton donor, exhibiting a huge pKa drop from 7.2 in the ground state to -7 in the excited state. The zwitterionic nature of the proton transfer product encourages intramolecular electron transfer away from the hydroxyl moiety to the distal ring, allowing for a large pKa jump in the excited state. This process is reversible, making the NM6HQ salts powerful transient superacids. We have investigated the excited-state proton transfer (ESPT) from NM6HQ salts to various basic solvents (alcohols, DMSO). A model has been developed that adequately describes the ion-dipole interactions in the ESPT geminate-recombination process. Our studies have shown that the counterion plays a large role in the ESPT. Likewise, initiation of cationic polymerization is controlled by the counterion. NM6HQ perfluoroalkylsulfonates appear to be the first molecules reported which are capable of initiating aliphatic epoxide polymerization at room temperature through a proton transfer mechanism.

Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 62-64)

Thesis (Ph.D.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 280-297)

Proefschrift Universiteit van Amsterdam. / Met bibliogr., lit. opg. - Met samenvatting in het Nederlands.

Techn. Univ., Diss., 2006--Darmstadt

Universiẗat, Diss., 2007--Frankfurt (Main). / Zsfassung in dt. und engl. Sprache.