This thesis deals with the current methods available for X-ray structure determination and with the crystal and molecular structure determination of five compounds using these methods. The five compounds are 1) [ 2,3-Bis (dimethylarsino)- 1, 1, 1,4, 4, 4-hexaf luorobut-2-ene-As,As]tricarbonyldiiodotungsten(II),Me₂AsC (CF₃):C (CF₃) AsMe₂WI₂(CO)₃ 2) Dimethylammonium trichlorotris(dimethylsulphoxide}-ruthenate(II) , [ ( (CE₃)₂ SQ)₃ RuCl₃ ]⁻ [ (CH₃)₂ NH ₂]+ 3) Dichlorotetrakis{dimethylsulphoxide)ruthenium(II), (Me₂SO)₄fRuCl₂ 4) 1,3,7-Triraethyl-2,6-dioxypuriae hydrochloride dihydrate (caffeine hydrochloride dihydrate), CH₁₁C1N₄0₂-2H₂0 .5) 1-Acetyl-3-benzamido-2-keto-4- (2,3, 4, 6-tetra-O-acetyl-β-D-glucopyranosyloxy)-Δ³-pyrroline, C ₂₇H₃₀N₂O₁₃ The structures of compounds 1), 2), and 3) were determined by Patterson syntheses, compound 4) by centrosymmetric direct methods and compound 5) by non-centrosymmetric direct methods. All structures were then refined using full-matrix least-sguares procedures. The relevant crystal data for all five compounds can be found in Table A In the tungsten compound [1) the tungsten atom is seven-coordinate with a distorted capped octahedral environment, the capping group being a carbonyl. The capped face consists of the two remaining carbonyl groups and one of the arsenic atoms from the bidentate ligand. The uncapped face contains the two iodine atoms and the remaining arsenic. Crystal data for the five compounds examined atom. The structure of the ruthenium compound [ 2) ] consists of two crystallcgraphically non-equivalent anions in the asymmetric unit linked by hydrogen bonding via dimethylammonium cations. The coordination geometry about the structurally similar anions is essentially that of an octahedron with the DHSO ligands being bonded to Ru via the sulphur atoms. The co-ordination geometry about the ruthenium atom for compound 3) is essentially octahedral with cis chlorine atoms; Of the four DMSO ligands three are S-bonded and one is O-bonded, the O-bonded ligand being trans to a S-bonded ligand. For caffeine hydrochloride [ 4) ] the fused ring system is essentially planar and protonated at the 9-positioh. The crystal contains two types of hydrogen bonding involving 0-H...C1 and N-H...0 interactions. The structure of compound 5) consists of a pyranose ring in the chair conformation with the four 0-acetyl substituents in equatorial positions; the pyranose ring is connected to a planar pyrroline ring via a β-oxygen bridge. / Science, Faculty of / Chemistry, Department of / Graduate

Customs administrations, worldwide, are adopting the trend towards risk-based processing of international cargoes as a means of facilitating trade. This has lead to the introduction of innovative processes ably supported by technology to realize improvements in customs effectiveness and overall efficiency. Widespread use of e-commerce in trade-customs transactions and exchanges, likewise necessitates complimentary technical support where Customs has need to intervene in a specific import, export or transit consignment. South African Revenue Service (SARS) is presently developing and enhancing its core competencies through training of its personnel in the disciplines of risk management, anti-smuggling and post clearance audit. It therefore becomes essential that these capacity building initiatives be complimented with the most appropriate tools for conducting cargo examination. The current physical examination process and inspection techniques are both time consuming and costly for business and render the goods liable to damage and theft. Recent historical events, specifically the 9/11 tragedy in New York, has caused international organizations such as the G8 and World Customs Organization (WCO) to consider the implications and effects of terrorism on international maritime transportation. The G8 adopted a Co-operative Action Plan on Security covering all aspects of transportation security and the WCO adopted a Resolution on Security and Facilitation of the International Supply Chain. Both initiatives aim to ensure safer and more secure maritime trade on the global scale. Fundamental to SARS Customs ability to successfully implement such measures are the following: Availability of advance electronic customs data Automated risk profiling and targeting capability Availability of non-intrusion inspectional devices (X-ray cargo scanners) to examine cargo. These three criteria are essential for SARS to participate in supply chain security initiatives and to facilitate the transportation of international consignment. Accordingly this research project explores how the external and internal environment impacts on SARS. It further critically analyses the core competencies and resource strengths of SARS. To support SARS in its effort and in its process of starting a project to improve controls and facilitation of goods at ports of entry within the Republic, this study explores and expounds on infrastructure and business application needs of SARS. Finally the research project concludes with a recommendation of the most effective approach towards the implementation of cargo scanner 'shared, outsourced service." / Thesis (MBA)-University of Natal, Durban, 2003.

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, 2015.

Advances in computer automation and control, compact and portable x-ray sources, and reliable and efficient detector systems over the last ten years have allowed X-Ray Determination of Residual Stress (XRDRS) measurements to become a viable method of evaluating the state of stress in metals, alloys, and ceramics. However, problems associated with incorrect XRDRS equipment operation and poor experimental technique are prevalent, necessitating better operator training and education. Therefore, an interactive computer workstation, called RS/hyper, was developed to lead the operator towards correct operating procedures and reliable experimental technique. RS/hyper teaches the operator proper machine setup, machine maintenance, radiation safety, experimental technique, theoretical understanding, and provides limited data evaluation. Graphical aids are used extensively to avoid confusion and misinterpretation during the learning process. Since RS/hyper is interactive, the operator may select the desired level of understanding on a particular topic. These topics are linked, through a hypertext interface, so that the information is presented coherently and efficiently. Compared to written texts and references, RS/hyper has been shown in preliminary tests to reduce XRDRS training and problem solving time by a factor of 16. RS/hyper will train novice users of XRDRS equipment so that the data acquired from such machines will be reliable in an industrial environment. Since the software educates the user, the results of the data will be more accurately represented before interpretation. The experienced user should find RS/hyper useful as a reference of XRDRS and related information. / Master of Science