Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Many fabrication processes for semiconductor nanostructures rely on the understanding of surface pattern evolution during crystal growth and etching. In this thesis, the morphological evolution of GaAs surfaces during thermal chlorine etching and molecular beam epitaxial growth is investigated by atomic force microsco…
The results of thermoelectric power and electron drift mobility in Al_xGa_{1-x}N lattice-matched to GaN are calculated for different temperatures, free-electron concentrations and compositions. The two-mode nature of the polar optic phonons is considered jointly with deformation potential acoustic, piezoelectric, allo…
Construction of functional supramolecular nanoassemblies has attracted great deal of attention in recent years for their wide spectrum of practical applications. Mesoporous silica nanoparticles (MSN) in particular were shown to be effective scaffolds for the construction of drug carriers, sensors and catalysts. Herein…
High throughput synthesis and screening methods were adopted for the search of new noble metal free oxide catalysts for the selective propane combustion in the presence of CO. The Ce20Ti50Cr30 catalyst was found as the best performing from ternary composition spreads. Through special optimisation routine, catalysts su…
A thesis in the Department of Chemistry submitted to the Faculty of Science and Agriculture in partial fulfilment of the requirements for the award of the degree of Doctor of Philosophy of the University of Zululand, 2009.
Glass fiber reinforced polymer composites find widespread applications these days in hostile environment due to their several advantages like high wear resistance, strength-to-weight ratio and low cost. The performance of the composites can further be improved by adding particulate fillers to them. To this end, this w…
The Nobel Prize for Physics 1920 was awarded to C.-E. Guillaume for his discovery of properties of nickel steels. He had previously observed that certain iron-nickel alloys exhibit the Invar effect i.e. an extremely low thermal expansion coefficient over a wide range of temperature. The decades since then have seen th…
Die vorliegende Arbeit entstand in enger Zusammenarbeit mit der international besetzten Cigré Arbeitsgruppe A3.17 “Surge Arresters“. In dem mehrere tausend MO-Widerstände (Metalloxid-Widerstände) umfassenden Versuchsprogramm wurden verschiedenste Prüfungen an MO-Widerständen, die derzeit für den Bau von Überspannungsa…
Currently, there is a great interest in the use of solid state materials for the storage of hydrogen. Hydrides of light elements may represent the only viable method of achieving a high weight percent and high volume density of stored hydrogen; sodium borohydride (NaBH4) has such features [1]. NaBH4 reacts with water…
The dissociation of CO 3 2− (pK = 2.4 ± 0.2) and precipitation of MgO (pL MgO = 10.66 ± 0.1) in a KBr melt at 800°C were studied potentiometrically with the use of a Pt(O2)|ZrO2|(Y2O3) membrane oxygen electrode. The direct calibration of the electrochemical circuit allowed only the equilibrium concentration of O2− (of…
A new microfluidic reaction system capable of mixing, sample transportation and reaction is developed for synthesis of alloy magnetic nanoparticles. It allows for a rapid and cost-effective approach to accelerate the synthesis of the nanoparticles. The system integrated a micro-mixer/micro-pump, a micro-condenser, mic…
Two approaches for creating a new all-cellulose composite material have been studied: the biosynthesis of compartmentalised bacterial cellulose fibril aggregates and the compression moulding of commercial chemical wood pulps processed with only water. The objective was to study the structural changes during processing…
In this thesis, we focus on theoretical study of adsorbates on metal and oxide surfaces that are important for surface chemistry and catalysis. Based on first principles calculations, the adsorption ofCO, NO, NO2, C4H6S2, C22H27SH and other molecules or radicals on nobel metal surfaces (gold and silver) are investigat…
The organizational self-assessment process came to maturity during the Total Quality Management (TQM) movement. Although varying forms of the process had been utilized for many years, the first mature self-assessments, known as self-appraisals, were performed as a criterion for the Malcolm Baldrige National Quality Aw…
This thesis discusses four-wave mixing (4WM) in a warm ensemble of rubidium using the diamond configuration level structure. Both classical 4WM and non- classical photon-pair production are investigated. Quantum information science has spawned a great amount of experimental work on the interaction of light with collec…
Interpretation of partial discharges arising in medium voltage cable connections requires detailed knowledge of impedance values which represent substation components. A technique is presented that allows online impedance measurement in substations and ring\nmain units (RMUs) without the need of switching. The measure…
In this work we present an investigation of the occurrence of conductivity on the surface of SrTiO3 due to argon ion bombardment. We created a model to describe this process and found that the temperature during the ion milling is a crucial factor for the conductivity. Depending on the temperatures we found surface ca…
Termoplásticos reforçados com fibra vegetal têm atraído a atenção de pesquisadores devido especialmente a sua vantagem relacionada à reciclabilidade. A baixa resistência ao impacto, especialmente em baixas temperaturas, limita as aplicações de alguns termoplásticos, como o polipropileno (PP). Para minimizar esta dific…
Water is an important substance. It is part of us, of our environment, and is a fundamental prerequisite for the existence of life as we know it. The structure of water is still, after over 100 years of research on the subject, however under debate. In this thesis x-ray absorption spectroscopy (XAS) and reverse Monte…
This report presents a unique core capable of accommodating oxide fuel and metal fuel and easy to change oxide core to metal core conforming to the design requirements. For the homogeneous oxide fueled core containing TRU (transuranics) fuel with 12% of the moderator pins, the results of calculation show the TRU conve…