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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Unimolecular and bimolecular reactions of alkyl radicals

Al-Niami, Kisma Hachim Ibrahim January 1988 (has links)
No description available.
142

Time-temperature-transformation (TTT) curves for and the thermal decompsition reactions of kaolinite, montmorillonite and two muscovite samples

Onike, F. N. January 1985 (has links)
No description available.
143

Some hydrogenations catalysed by nickel supported on well-defined magnesia and carbon

Payne, Christopher January 1988 (has links)
No description available.
144

Mechanistic studies of photodecarboxylation of arylacetic acids and photodehydration of hydroxybiphenyl and hydroxyterphenyl methanols

Xu, Musheng. 10 April 2008 (has links)
No description available.
145

Synthesis, Stability, and Reactions of Dichloroketene

Liddel, Harold Glenn 06 1900 (has links)
The primary objective of this work was to prepare dichloroketene.
146

Addition Reactions of Some Aromatic Aldazines

O'Dell, Stewart 08 1900 (has links)
The paper explores the conclusion that the addition compound was bicyclic, and that the addition of each of the two moles of cyanic acid was dependent upon the other.
147

Kinetics of Reactions of Substituted Group VI B Metal Carbonyls with Phosphites

Rettenmaier, Albert J. 08 1900 (has links)
The problem with which this investigation is concerned is twofold. The initial part of the problem was to prepare a non-sterically demanding bidentate phosphine ligand, 1,2-bis-(Phosphino)ethane, (P-en), and to determine the kinetics of (P-en)Mo(CO)4 with phosphites via spectrophotometric methods in an attempt to determine if steric effects are directing the type of mechanism followed.
148

Synthesis and properties of bicyclic compounds with a bridgehead nitrogen

Mouat, Deborah J. January 1989 (has links)
No description available.
149

Mechanistic electrochemistry

Williams, Nia Ann January 2000 (has links)
No description available.
150

Fine structure of the Isovector Giant Dipole Resonance: a survey with the (p,p') reaction at zero degrees

Jingo, Maxwell 05 August 2014 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, 2014. / This investigation involves a survey of the fine structure phenomenon of the Isovector Giant Dipole Resonance (IVGDR) over a wide mass range of nuclei, from 27Al, 40Ca, 56Fe, 58Ni to 208Pb, using inelastic proton scattering at 200 MeV. Proton detection is accomplished using the recently commissioned zero-degree facility of the K600 magnetic spectrometer at iThemba LABS. Inelastic proton experiments at zero degrees are very selective to excitations with low angular momentum transfer, and therefore ideal for studies of the IVGDR. This is because such experiments simplify the analysis of the many contributions to the spectra due to the complex nature of the nuclear interaction. The ability to make precise measurements of the properties of the IVGDR demonstrated by this work opens up new challenges to both experimental and theoretical work in nuclear structure. This is a survey of the (p,p′) reaction at zero degrees as a probe to study properties of the GDR and also the low energy E1 strength with high energy-resolution. Such a data base will provide more stringent tests of nuclear theory and the progress is seen in the details obtained. These tests can only be described by microscopic models including complex degrees-of-freedom. This should lead to new insights into the underlying interactions responsible for the nature of the electric dipole strength in nuclei. In the present study, double-differential cross-sections were converted to equivalent photo-absorption cross-sections and their results compared to previously published photo-absorption data. An excellent correspondence in the excitation-energy region of the Giant Dipole Resonance (GDR) was noticed between the two data sets. The fine structure observed can be described using characteristic energy scales, arising mainly from Landau damping (even though the spreading width may also play a role). The extraction of these characteristic energy scales which are a signature for the decay process was achieved through the use of wavelet analysis. Furthermore, thanks to the recent advances in computational power and techniques, microscopic shell model-based calculations lead to new insights into the underlying properties of the nuclear interaction which are responsible for the collective behaviour evidenced by the existence and properties of the IVGDR. In addition to the extraction of characteristic energy scales, this study also provides level densities of J = 1− states. In order to extract nuclear level densities, there is need to eliminate instrumental background and other contributions to the spectra from (p,p′) scattering using the model-independent Discrete Wavelet Transform (DWT) method. Level densities of J = 1− states are determined using the fluctuation analysis technique and comparisons are made with the phenomenological Back Shifted Fermi Gas (BSFG) model predictions, calculations of the Hartree Fock- Bogoluibov (HFB) microscopic model and Hartree Fock-Bardeen-Cooper-Schrieffer (HF-BCS) predictions. Finally, this survey will simultaneously provide bench-marks on the capabilities and limitations of the new zero-degree facility important for planning of the future experimental work.

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