京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第24001号 / エネ博第437号 / 新制||エネ||82(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)准教授 高井 茂臣, 教授 萩原 理加, 教授 佐川 尚 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM

The National Credit Act 34 of 2005 introduced measures in an attempt to prevent overspending by consumers and, more importantly measures to prevent credit providers from lending money to consumers who cannot afford either to pay the loan amount or the interest on the loan amount. A debtor who becomes over-indebted may apply for debt review. The NCA also provide for the reorganisation of debt of a person who is overindebted, to afford such person the opportunity to survive the immediate consequences of his financial distress. Its purpose is to inter alia, prevent reckless credit granting and address the problem of over-indebted and in particular to protect the consumer. The sequestration process in terms of the Insolvency Act 24 of 1936 may provide debt relief to individual debtors because following the sequestration order the debtor may be rehabilitated. Rehabilitation has the effect of discharging all pre-sequestration debt and further relieving the debtor of every disability resulting from sequestration. The debtor can apply sequestration by way of voluntary surrender while it is possible for a creditor to sequestrate a debtor's estate by way of compulsory sequestration. The process of compulsory sequestration is often used as a debt relief measure in form of a so-called friendly sequestration. In a friendly sequestration the debtor will arrange with a friend or a family member to whom he owes a debt that he will commit an act of insolvency in terms of section 8(g), that is, where the debtor gives written notice to a creditor that he is unable to pay all or any of his debts. When enacting the NCA, the legislature did not specifically make any mention of the Insolvency Act. The question is whether the NCA impact on the Insolvency Act. However the court in Ex Parte Ford And Two Similar Cases 2009 3 SA 376 (WCC) held that section 85 of the NCA was applicable to proceedings under voluntary surrender. The court further held that an application for voluntary surrender should not be granted where the machinery of the NCA was the appropriate mechanism to be used. In Investec Bank. v Mutemeri 2010 1 SA 265 (GSJ) the court held that section 130(1) do not apply to sequestration because an application for sequestration is not application for enforcement of the sequestrating creditor‟s claim. It is therefore not subject to the requirement of section 130(1) of the NCA. The court also held that an application by a credit provider for the sequestration of a consumer does not constitute litigation or a judicial process in terms of section 88(3). On Appeal in the case of Naidoo v Absa (391/2009)[2010] ZASCA 72 (27 May 2010) the Supreme Court of Appeal confirmed the decision of Mutemeri. The appeal court held that a credit provider need not to comply with section 129(1)(a) before instituting sequestration proceedings against a debtor. The research will be conducted as to whether the NCA impact on the Insolvency Act. / Dissertation (LLM)--University of Pretoria, 2011. / Mercantile Law / unrestricted

The National Credit Act (hereinafter the Act) introduced debt review to the Republic of South Africa in 2007. Debt review was introduced to provide debt relief to over-indebted consumers. The legislature was not able to foresee and address several implementation obstacles and accordingly courts are forced to assist in the interpretation of the Act. Courts have created some legal certainty, but there are different opinions on the correctness of these interpretational principles. This study will consider current precedents and whether the current precedents are in accordance with the intention of the legislature. Section 2 of the Act stipulates that Act should be interpreted to give effect to the purposes of the Act. The purpose of the Act is contained in section 3. One of the purposes of the Act is to promote equality between the rights of consumers and credit providers in credit agreements. This dissertation illustrates that the Act aims to achieve this equality of rights in the debt review process by the inclusion of countervailing rights in part D of chapter 4 of the Act. The legislature considered recommendations made by certain role players in the debt review process. Proposed amendments were published on 29 May 2013 in the Government Gazette for public consideration. These proposed amendments were considered in the scope of this study. The dissertation concludes that the proposed amendments need to be supplemented in order to ensure that debt review becomes and remains an effective debt relief measure for over-indebted consumers, without prejudice to the rights of credit providers. / Dissertation (LLM)--University of Pretoria, 2014. / Mercantile Law / unrestricted

No description available.

A simple adhesion test method is proposed to provide estimates of the debond toughness of adhesive bonds. Notched coating adhesion (NCA) specimens consist of single substrates coated with thin layers of adhesive. The coating is notched to induce initial debonds, and the specimen is then loaded in a manner to produce tensile stresses in the coating. The substrate strain at which the coating debond propagates is then used to determine the critical strain energy release rate. Yielding of the substrate is permitted, and does not complicate the calculations. The specimen geometry results in a mode mix which drives the debond to the interface, thus obtaining a measure of interfacial behavior. Because of the geometry and testing method, the technique is simple, inexpensive and may be conducted quickly. The properties of the coating and the residual stresses of the bond must be known to predict the bond strength. Since accurate data on these properties are not always readily available, the test may be limited as a method to screen adhesive systems. Besides being a screening test, the NCA can be used as an accelerated test to study the durability of adhesive bonds. NCA specimens reach moisture equilibrium quickly because of the short diffusion path. By significantly reducing the amount of time needed for the adhesive/substrate interface to reach equilibrium moisture conditions, the time required to obtain estimates of performance in humid environments is greatly reduced. If one assumes that moisture at the interface is the cause of bond degradation, these simple tests offer the potential to rapidly estimate the durability of a given adhesive/substrate system. Accelerated durability studies were conducted on model steel/epoxy systems, and the results were compared to the results for double cantilever beam tests. / Master of Science

Die vorliegende Arbeit beschäftigt sich mit der Synthese und den Eigenschaften von linearen und verzweigten amphiphilen Polypeptid-Blockcopolymeren. Die Frage nach dem Einfluss der Topologie und Konformation der Blockcopolymere auf die supramolekularen und kolloidalen Eigenschaften bildete einen wichtigen Aspekt bei den Untersuchungen. Die Blockcopolymere wurden nach einem mehrstufigen Reaktionsschema durch Kombination von anionischer und ringöffnender Polymerisation von Aminosäuren-N-Carboxyanhydriden (NCA) synthetisiert. Die Untersuchung der Polypeptid-Blockcopolymere hinsichtlich ihres Aggregationsverhaltens in fester Phase sowie in verdünnter wässriger Lösung erfolgte mittels Streumethoden (SAXS, WAXS, DLS) sowie abbildender Methoden (TEM). Durch Einsatz der Blockcopolymere als polymere Stabilisatoren in der Emulsionspolymerisation wurden Oberflächen funktionalisierte Latizes erhalten. Als Beispiel für eine pharmazeutische Anwendung wurden bioverträgliche Polypeptid-Blockcopolymere als Wirkstoff-Trägersysteme in der Krebstherapie eingesetzt. / This work describes the synthesis and characterization of linear and branched polypeptide block copolymers having amphiphilic character. The studies focused on the impact of the block copolymers' conformation and architecture on the supramolecular and colloidal properties. The polypeptide block copolymers were prepared in a multi-step process involving the anionic synthesis of (poly)amino-functional polymers (polystyrene and polybutadiene) which where used as macroinitiators for the ring-opening polymerization of N-carboxyanhydrides (NCA) of protected a-aminoacids. Supramolecular structures of the block copolymers in the solid state as well as in diluted aqueous solution were investigated using scattering (SAXS, WAXS, DLS) and microscopic (TEM) methods. Both linear and branched polypeptide block copolymers were used as polymeric stabilizers in the emulsion polymerization of styrene to yield polypeptide-decorated latexes. Biocompatible block copolymers were used as drug-delivery systems in lymphatic cancer therapy.

L'optimisation de la durée de vie d'une batterie nécessite la prédiction de son vieillissement et donc l'identification des mécanismes de vieillissement qui en sont à l'origine. Pour pallier les limitations des outils de caractérisation du vieillissement classiquement utilisés (mesures intermittentes de performance au cours du vieillissement et tests de caractérisation post-mortem), des outils d'étude non destructive de l'état des électrodes en cours de vie ont été mis au point et testés. Il s'agit d'un modèle multiphysique de fonctionnement de la batterie lithium-ion et de deux méthodes d'extraction de paramètres in-situ : la première basée sur le traitement de la dérivée du profil de tension et la seconde sur la différence des pentes de profils de tension entre l'état neuf et l'état considéré. Les paramètres non disponibles mais nécessaires à l'établissement du modèle multiphysique d'un élément ont été estimés pour différents états de charge et différentes températures. Ce modèle a été validé par comparaison avec des mesures expérimentales. L'application de ces outils est illustrée dans le cas de trois mécanismes de vieillissement différents. En outre, ces outils ont été plus particulièrement appliqués au vieillissement par dépôt de lithium. L'utilisation du modèle de l'élément commercial VL41M Saft a permis de dresser un abaque de ses courants limites de fonctionnement et a fait l'objet d'une validation expérimentale mettant en oeuvre la méthode dite de la dérivée / Optimisation of a battery life time requires the prediction of its ageing and the identification of the involved ageing mechanisms. In order to avoid the limitations due to standard ageing characterisation methods (performance evaluations conducted regularly along ageing and post-mortem characterisations), other tools allowing assessment of the electrode state without deterioration along the life time, have been tested. It concerns a multiphysic model of lithium-ion battery and two methods for in-situ parameter extraction: the first is based on the study of the derivative of the tension profile and the second one, on the difference between the slope of the tension profiles at the fresh state and at the considered state. The non-available parameters required for set up of the multiphysic model for one battery have been evaluated for different states of charge and various temperatures. This model has been validated by comparison with experimental measurements. The application of these tools is illustrated for three different ageing mechanisms. Moreover these methods have been especially applied for the case of lithium plating ageing. Use of the VL41M Saft model allowed to set up an abacus of the limiting charge currents and an experimental validation has been performed in using the method so-called derivation method

Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2008. / This dissertation can be broken into two parts comprising different strategies to synthesise novel poly-amino acid based polymers. The use of recently developed nickel(0) and cobalt(0) metal catalysts for the living polymerization of α-amino acid-N-carboxyanhydrides (NCAs) to synthesise novel poly-amino acid polymers, comprising a polar, hydrophilic block and a neutral hydrophobic block, were investigated in the first part of this study. The hydrophilic block was made up of a random sequence of arginine (Arg, R), glycine (Gly, G) and aspartic acid (Asp, D) - poly-RGD. This was followed by a polyleucine (Leu, L) hydrophobic block. Success was limited with this system due to polymer precipitation during the polymerization reaction. Because of this precipitation, the amino acid composition of the hydrophilic block was changed to a random sequence of glutamic acid (Glu, E), cystein (Cys, C) and aspartic acid – poly-ECD. Here also, the success was limited because of polymer precipitation. A novel approach to the synthesis of hybrid poly-amino acid – synthetic polymer materials constitutes the second part of this study. The final polymeric structure can be described as a carboxylic acid functionalized polyethylene glycol (PEG) sheathed polylysine polymer. The technology involves the synthesis of a lysine NCA functionalized at the ε-amino group with an α,ω-bis(carboxymethyl) ether PEG. The distal carboxylic acid group was protected as a benzyl ester during synthesis and subsequent polymerization of the PEG-lysine-NCA macro-monomer. The polymerization was successfully initiated using n-butyl amine to form short homopolymer strands. Copolymerization with lysine-NCA was also achieved as well as the successful initiation using a generation 1.0 dendritic amine initiator, N,N,N’,N’-tetrakis(3-aminopropyl)-1,4-butanediamine (DAB-Am-4). These polymers were characterized by 1H NMR.

This dissertation considers the possible impact of certain requirements of the National Credit Act 34 of 2005 (hereafter “NCA”) on ordinary civil procedural rules relating specifically to debt enforcement procedures. It further identifies problem areas created by some of the provisions of the NCA in this regard, and ultimately proposes potential solutions thereto. However, as indicated in various sections of the dissertation, it is not always clear what the legislature had in mind with certain provisions. This uncertainty calls for interpretation, which gives rise to further confusion in certain instances. In view of the aims of the NCA as stated in section 3 thereof, as well as various procedural provisions discussed in this dissertation, it is clear that the NCA mainly has the protection of the consumer at heart when devising procedures relating to, or ancillary to debt enforcement procedures utilised by credit providers to collect outstanding debt sounding in money. Since the NCA must operate within an existing legal system and procedural regime where certain terms have become entrenched, a broad background on some legal concepts and relevant civil procedures are provided where after the impact of the NCA thereon is considered and analysed. As the NCA will only affect general civil procedure where a credit provider attempts to enforce obligations to which the NCA applies, the exact application of the NCA and the general enforcement procedures contained therein are determined. Against this background the impact of specific procedures prescribed by the NCA on existing rules of civil procedure are critically analysed. This dissertation illustrates that although the NCA improves the position of the consumer in many ways, also with regard to debt enforcement procedures, the legislature should have drafted some provisions more carefully which would have resulted in some vital issues being clearer. Although practice and precedent will eventually even out many of the practical difficulties currently experienced it will take time and money to do so. It is therefore submitted that some areas should be reconsidered for amendment by the legislature in order to allow this significant piece of legislation to operate smoothly. Ultimately, two sets of conclusions are drawn together in this dissertation. Firstly, the general conclusions relating to the impact of the NCA on general civil debt enforcement procedures are stipulated and, secondly, specific areas that should be reconsidered by the legislature in order to allow the NCA to function optimally are identified. Copyright / Dissertation (LLM)--University of Pretoria, 2010. / Procedural Law / unrestricted

In this thesis I investigate several aspects of local quantum criticality, a concept of key importance in a number of physical contexts ranging from critical heavy fermion compounds to quantum dot systems. Quantum critical points are associated with second order phase transitions at zero temperature. In contrast to their finite-temperature counterparts, the zero-point motion cannot be neglected near a quantum critical point. As a result, the incorporation of quantum dynamics leads to an effective dimension larger than the spatial dimension of the system for the order parameter fluctuations within the Ginzburg-Landau-Wilson treatment of criticality. This so-called quantum-to-classical mapping works well for the critical properties in insulating systems but apparently fails in systems containing gapless fermions. This has been experimentally most clearly been demonstrated within a particular class of intermetallic compounds called heavy fermions. A particular way in which the Ginzburg-Landau-Wilson paradigm fails is for critical Kondo destruction that seems to underlie the unconventional quantum criticality seen in the heavy fermions. I focus on studying the properties of critical Kondo destruction and the emergence of energy-over-temperature-scaling in systems without spatial degrees of freedom, i.e., so-called quantum impurity systems. In particular, I employ large-N techniques to address critical properties of this class of quantum phase transitions in and out of equilibrium. As quantum critical systems are characterized by a scale-invariant spectrum with many low-lying excitations, it may appear that any perturbation can lead to a response beyond the linear response regime. Understanding what governs the non-linear response regime near quantum criticality is an interesting area. Here, I first present a path integral version of the Schrieffer-Wolff transformation which relates the functional integral form of the partition function of the Anderson model to that of its effective low-energy model. The equivalence between the low-energy sector of the Anderson model in the Kondo regime and the spin-isotropic Kondo model is usually established via a canonical transformation performed on the Hamiltonian, followed by a projection. The resulting functional integral assumes the form of a spin path integral and includes a geometric phase factor, i.e. a Berry phase. The approach stresses the underlying symmetries of the model and allows for a straightforward generalization of the transformation to more involved models. As an example of the efficiency of the approach I apply it to a single electron transistor attached to ferromagnetic leads and derive the effective low-energy model of such a magnetic transistor. As Kondo screening is a local phenomenon, it and its criticality can be studied using the appropriate impurity model. A general impurity model to study critical Kondo destruction is the pseudogap Bose-Fermi Kondo model. Here, I concentrate on the multi-channel version of the model using the dynamical large-N study. This model allows to study the non-trivial interplay between two different mechanisms of critical Kondo destruction. The interplay of two processes that can each by itself lead to critical Kondo destruction. The zero-temperature residual entropy at various fixed points for the model is also discussed. The two channel Anderson model exhibits several continuous quantum phase transitions between weak- and strong-coupling phases. The non-crossing approximation (NCA) is believed to give reliable results for the standard two-channel Anderson model of a magnetic impurity in a metal. I revisit the reliability of the NCA for the standard two channel Anderson model (constant conduction electron density of states) and investigate its reliability for the two-channel pseudogap Anderson model. This is done by comparing finite-temperature, finite-frequency solutions of the NCA equations and asymptotically exact zero-temperature NCA solutions with numerical renormalization-group calculations. The phase diagram of this model is well established. The focus here will be on the dynamical scaling properties obtained within the NCA. Finally, I study the thermal and non-thermal steady state scaling functions and the steady-state dynamics of the pseudogap Kondo model. This model allows us to study the concept of effective temperatures near fully interacting as well as weak-coupling fixed points and compare the out-of-equilibrium scaling properties of critical Kondo destruction to those of the traditional spin-density wave (SDW) scenario. The differences I identify can be experimentally probed. This may be helpful in identifying the nature of the quantum critical points observed in certain heavy fermion compounds.