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Meter a lapse of about five years the experimental attack on the secrets of the otomio nucleus hau begun again. The num her of ocientistr3 now engaged in this work and the number of particle decelerators which exact or are under coaztruction are very much greater than at any other p rcviouo time. 1ý Since the gar there have emerged several new promising methods of accelerating particles to very high enargiea. In every case the size, expense and time of eonmtruction of the o, pnratu3 are very 1nrge. The machine which is most suitable for accelerating particles to the highest energies is the proton synchrotron. Until recently this development wes confined to the BirminChe. n University, whore a machine designed to' accelerate protons to 109 eV (and possibly deuterons and of -particles to "6x 109 aV and 109 eV reapoctinely) in v2cll under construction. It id with the theory and construction of such an accelerator that this thesis is mainly concerned (Chapters III, IV and V). While building ouch a complicated picco of apparatus it in bf course essential to appreciate its likely uses. Since the proton synchrotron will be capable of deliýrering pcrtiolea over a very viide ranee of energies (protons from 2 ý- 1,000 MoV) the possible experim©nta are likely to include nearly all thoac cihich can be performed with arty accelerator. Naturally attention will be confined largely to the very high energy region.

Thesis (PhD)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Please see full text for abstract / AFRIKAANSE OPSOMMING: Sien volteks vir opsomming

The Zero Degree Calorimeter at STAR was used to calculate an asymmetry from small-angle scattering of neutral particles from proton-proton collisions at a center-of-mass energy of 500 GeV. An energy-centroid method was used to define hit positions of the neutral particles for each Shower Maximum Detector plane. An angular asymmetry analysis was done using these positions to measure both a left-right and a top-bottom asymmetry. The asymmetries were then used to calculate transversely-normal and sideways beam-polarization components for both of RHIC’s polarized-proton beams. The results of this analysis show that the Zero Degree Calorimeter Shower Maximum Detectors can be used as effective polarimeters at high beam energies, and can check the functionality of the spin rotators for longitudinally-polarized beams. The results of this analysis will be used in measurements that further the understanding of the source of a proton’s spin. / Department of Physics and Astronomy

The rate of destruction of 18F via the 18F + p reactions is of importance in both novae and X-ray burster explosive scenarios. The rate of the competing destructive reactions, 18F(p,γ)19Ne and 18F(p,α)15O, depend upon the level structure of the compound nucleus 19Ne. The first experiment in this thesis examines the level structure of 19Ne about the 18F + p threshold via elastic 15O(α,α)15O scattering. The experiment was performed at the CRC Louvain-la-Neuve. A radioactive 15O beam bombarded a thick 4He gaseous target with elastically scattered alpha particles detected using segmented silicon detectors. An R-matrix approach was used to analyse the data and extract the resonance parameters Er and Ѓα. Particular emphasis was placed on extracting information regarding the possible 3/2+ doublet, the parameters of which, to date, have been inferred from the mirror nucleus 19F. The nominal values for the doublet taken from the mirror are Er = 8 and 38 keV, with Ѓα = 0.27 and 1.3 keV respectively. Following this new analysis it has been found that the doublet straddles the threshold at Er = -22 and 3 keV, with Ѓα = 0.15 and 3.3 keV respectively. S-factor calculations and interference effects were also examined. The 18Ne(α,p)21Na reactions is believed to be a key process in X-ray bursters. It is thought to be a possible HCNO-breakout reaction; the mechanism responsible for producing energy to drive the X-ray burster. To date the reaction has been studied both directly and indirectly. The results from each previous experiment show su cient discrepancies to warrant a re-examination of the reaction rate. As such, the second experiment presented in this thesis revolves around a new direct measurement of 18Ne(α,p). The experiment was undertaken at the CRC Louvain-la-Neuve, where, a radioactive 18Ne beam impinged upon a thin gaseous 4He target. The beam energy was chosen to provide data points in common with previous experiments at Er = 1.7 and 2.5 MeV. Reaction protons were detected via a segmented silicon detector telescope system. The total cross section calculated at Er = 2.5 MeV is 1.22 0.151 mb. An upper limit for the cross-section of 0.0208 mb was evaluated at Er = 1.7 MeV.

Field Programmable Gate Arrays (FPGAs) provide a reconfigurable asset in the design of space computing. â Hardwareâ configurations are stored in FPGA memory elements, which are susceptible to Single Event Upsets (SEUs). What is the best way to detect and mitigate SEUs and correct them before they become functional errors? The Configurable Fault Tolerant Processor (CFTP) consists of a controller FPGA (X1) controlling an experiment FPGA (X2), which can be used to test different fault-mitigation techniques. This focus of this thesis was to develop and execute a radiation test plan to evaluate different experiments in a proton radiation beam at Crocker Nuclear Laboratory, Davis, CA. A shift register was designed to determine a proton flux conducive to SEU observation. The shift register was also modified to create two additional configurations, implemented with the memory elements of the Look-Up Table and Flip-flops within an FPGA Configurable Logic Block. The data collected from this program was then analyzed for SEU rates and fault susceptibility. This data was extrapolated using a radiation environment model to predict the on-orbit SEU-rate for CFTP in the NPSAT1 orbit of 560 km, 35.4 degrees inclination, as well as Virtex II FPGAs and at 1000 and 1500 km altitudes.

This thesis is divided into two parts. In Section I a description is given of a liquid hydrogen bubble chamber expansion system designed for use with the Imperial College 40cm. hydrogen chamber, and as a prototype system for the 150 cm. British National chamber. Section II contains a study of - proton interactions at an incident pion momentum of 4 Gev/c. The Saclay 81cm. liquid hydrogen bubble chamber was exposed to a beam from the CERN proton synchroton, and produced 60,000 useful pictures. The analysis of those events with two charged secondaries, excluding strange particle events, is presented. Chapter II reviews the background to and objectives of the experiment. In Chapter III an account is given of the apparatus and methods used in the processing of the film. The individual identification of events is described in Chapter IV. Cross-sections, angular and momentum distributions, and resonance production for the different reaction channels are presented and discussed in Chapters V and VI. Finally in Chapter VII, a brief description is given of some preliminary results of an investigation of +-proton interactions of 4Gev/c.

by Edwina Po Sau Man. / The "0" & "1" in the title are subscripts. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 81-86). / Abstract --- p.II / Acknowledgment --- p.IV / Abbreviations --- p.V / List of Tables --- p.VIII / List of Figures --- p.IX / Table of Contents --- p.XII / Chapter Section 1 --- Introduction --- p.1 / Chapter 1.1 --- Photosynthesis --- p.1 / Chapter 1.2 --- Site of Photosynthesis --- p.3 / Chapter 1.3 --- The Structure of ATPase --- p.6 / Chapter 1.3.1 --- Functions of the Subunits of CF1 --- p.9 / Chapter 1.3.1.1 --- The ε - Subunit --- p.9 / Chapter 1.3.1.2 --- The δ - Subunit --- p.9 / Chapter 1.3.1.3 --- The γ- Subunit --- p.10 / Chapter 1.3.1.4 --- The α- and β- Subunits --- p.10 / Chapter 1.4 --- "Photosynthetic Electron Transport, Δ pH and Phosphorylation inside Chloroplasts" --- p.12 / Chapter 1.5 --- Pesticides --- p.16 / Chapter 1.5.1 --- Paraquat --- p.17 / Chapter 1.5.2 --- Carbamates --- p.20 / Chapter 1.6 --- Objectives of the Study --- p.21 / Chapter Section 2 --- Materials and Methods --- p.22 / Chapter 2.1 --- Apparatus --- p.22 / Chapter 2.2 --- Materials --- p.24 / Chapter 2.2.1 --- Reagents and Buffers for assay of Proton Transport --- p.25 / Chapter 2.2.2 --- Pesticides --- p.26 / Chapter 2.2.3 --- Buffers for SDS-PAGE --- p.27 / Chapter 2.2.4 --- Reagents of Bradford Protein Assay --- p.31 / Chapter 2.3 --- Methods --- p.32 / Chapter 2.3.1 --- Determination of ChlorophyllContent --- p.32 / Chapter 2.3.2 --- Determination of Protein Content in Chloroplast Thylakoids --- p.33 / Chapter 2.3.3 --- Measurement of Proton Transport --- p.34 / Chapter 2.3.3.1 --- Pesticide Concentration Study --- p.36 / Chapter 2.3.3.2 --- Time Course Study --- p.36 / Chapter 2.3.3.3 --- Kinetic Analysis of the Effects of Pesticides on Chloroplast Thylakoids Before and After Illumination --- p.37 / Chapter 2.3.3.4 --- Study of the Combined Effects of Two Pesticides --- p.37 / Chapter 2.3.4 --- Effect of Pesticides on Chloroplast Membranes by SDS-PAGE --- p.38 / Chapter Section 3 --- Results --- p.39 / Chapter 3.1 --- Pesticide Concentration Study --- p.39 / Chapter 3.1.1 --- Paraquat Dichloride --- p.39 / Chapter 3.1.2 --- Methyl Carbamate --- p.41 / Chapter 3.1.3 --- Ethyl Carbamate --- p.43 / Chapter 3.1.4 --- Pyridinol Carbamate --- p.45 / Chapter 3.1.5 --- Pyrrolidinedithiocarbamate --- p.47 / Chapter 3.1.6 --- Diethyldithiocarbamic Acid --- p.49 / Chapter 3.1.7 --- Summary of the Pesticides Concentration Study --- p.51 / Chapter 3.2 --- Time-course Study --- p.52 / Chapter 3.3 --- Kinetic Analysis of the Effects of Pesticides on Chloroplast Thylakoids Before and After Illumination --- p.53 / Chapter 3.3.1 --- Paraquat Dichloride --- p.53 / Chapter 3.3.2 --- Methyl Carbamate --- p.56 / Chapter 3.3.3 --- Ethyl Carbamate --- p.57 / Chapter 3.3.4 --- Pyridinol Carbamate --- p.58 / Chapter 3.3.5 --- Pyrrolidinedithiocarbamate --- p.59 / Chapter 3.3.6 --- Diethyldithiocarbamic Acid --- p.60 / Chapter 3.4 --- Combined Effects of Paraquat and Carbamates --- p.61 / Chapter 3.4.1 --- Paraquat and Methyl Carbamate --- p.61 / Chapter 3.4.2 --- Paraquat and Ethyl Carbamate --- p.64 / Chapter 3.4.3 --- Paraquat and Pyridinol Carbamate --- p.66 / Chapter 3.4.4 --- Paraquat and Pyrrolidinedithiocarbamate --- p.69 / Chapter 3.4.5 --- Paraquat and Diethyldithiocarbamic Acid --- p.71 / Chapter 3.5 --- Gel Electrophoresis --- p.73 / Chapter Section 4 --- Discussion --- p.75 / Chapter Section 5 --- Conclusion --- p.80 / Chapter Section 6 --- References --- p.81 / References --- p.81 / Appendix I Kinetic Analysis of Pesticides with Chloroplast Thylakoids upon Illumination --- p.87 / Appendix II Kinetic Analysis of Pesticides with Chloroplast Thylakoids in the Dark --- p.88 / Appendix III The Initial Rate of Proton Transport in Chloroplast Thylakoids with Different Pesticides --- p.89 / Appendix IV The Conversion of Equivalent Protons from pH Changes --- p.90 / Appendix V Calculation of Proton Transport (%) --- p.91 / Appendix VI Determination of Protein Content in Chloroplast Thylakoids --- p.92 / Appendix VII Calculaiton of Relative Mobility (Rf) --- p.93

L’électrolyse est une technologie qui permet de répondre à deux problématiques cruciales. D’une part, répondre au besoin en stockage d’énergie liée à l’intégration de sources intermittentes sur les réseaux électriques. D’autre part, répondre à la croissance de la demande en hydrogène, liée aux marchés naissants de l’hydrogène énergie. La nature des besoins liés au développement de la technologie d’électrolyse implique des sollicitations intermittentes dont les impacts quant au fonctionnement du système sont encore méconnus. En ce sens, et face aux manques de la littérature quant à la modélisation à l’échelle système de la technologie d’électrolyse PEM, un nouveau modèle est développé. Pour cela, le formalisme de modélisation graphique Bond Graph est utilisé, notamment pour sa capacité à représenter tout type d’échange énergétique de manière unifiée. Le modèle développé permet de représenter l’intégralité d’un système d’électrolyse PEM, ses différents composants et lois de contrôle associées. Il est validé sur la base du comportement dynamique d’une installation semi-industrielle disponible au CEA. Ce modèle est ensuite utilisé pour identifier et comprendre les enjeux liées à une sollicitation intermittente d’un système d’électrolyse PEM d’un point de vue de l’efficacité du système, de sa flexibilité et de sa capacité de suivi de charge, de sa fiabilité, de sa sûreté ou encore de sa durabilité. Différentes modifications de conception sont simulées et évaluées à la lumière de ces différents enjeux. Finalement, le modèle Bond Graph est exploité d’un point de vue de ses propriétés structurelles afin d’analyser les conditions de surveillabilité d’un système d’électrolyse PEM. / PEM Electrolysis is a technology which to enable to face two major challenges : (i) Fulfill the need of energy storage caused by the integration of intermittent energy sources on electricity networks; (ii) Cope with the growing need of carbon free hydrogen caused by the future market applications of hydrogen energy. These particular needs, regarding electrolysis technology development, involve an intermittent operating mode which impacts on the dynamic behavior of the system remain unknown. Modelling is a critical tool to understand these issues and provide a thorough analysis. State of the art of existing modelling works highlighted that only a few models take into account the dynamic of the whole system including Balance of Plant. Therefore a new dynamic and multiphysic model was developed under Bond Graph formalism. This graphical modelling formalism was selected especially thanks to its ability to represent any kind of power exchange in a unified way. The model enables to represent the whole system including balance of plant and associated control laws. It is validated on the dynamic behavior of an experimental device available in CEA. The model is then used in order to identify and understand the issues related to intermittent operation of a PEM electrolysis system. These issues are related to system efficiency, flexibility, reliability, safety and durability. Regarding these issues, some design changes are simulated and assessed. Finally, the Bond Graph model and its structural properties enable to perform diagnosis and monitorability analyses of a PEM electrolysis system.

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