A programme of research on agricultural guanidine fungicides, represented by a complex mixture of several components (guazatine) and by a single compound (dedine[?] ), was carried out. The studies involved the synthesis of several guanidine derivatives and their characterization by spectroscopic methods such as carbon-13 NMR, MS. and FAB/MS. The synthetic routes have been described and different routes for the preparation of guazatine were also established.

People with disabilities, and in particular people who are blind or vision impaired, are not embracing computing and Internet-related technologies at the same rate as the able-bodied population. The purpose of this study was to find the reasons behind this digital divide for people with disabilities and provide solutions. The investigation into this 'disability divide' initially examined the historical significance of the social construction of disability, the developments of computing and Internet-related technologies and the evolution of associated government and corporate policies. In order to gain an understanding of the specific elements in the current disability divide, interviews were conducted with a range of government representatives, multinational information technology developers and online information providers in Australia and the United States of America. In order to gain an understanding of what people with disabilities required from information technology, a national survey was conducted with people who are blind or vision impaired to determine their computing and Internet experiences. This study clearly identified that people with vision disabilities have a high level of computing and Internet expertise and it is specific barriers, rather than lack of will, that has prevented access to computing and Internet-related technologies. These barriers include issues relating to the perception of disability in society, Federal and state government policy, corporate policy, mainstream computing products, assistive technologies, real-time online communication, poverty and a lack of educational opportunities. Addressing the issues in these areas will significantly reduce the impact of the disability divide, allowing people who are blind or vision impaired to participate more effectively in the information age.

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Die vorliegende Dissertation beschäftigt sich hauptsächlich mit zwei Fragen: Erstens, welche Faktoren beein-flussen den Prozess, durch den sich neue Technologien unter Firmen verbreiten? Zweitens, welche Konsequen-zen ergeben sich aus der Verbreitung neuer Technologien? Beide Fragen beschäftigen sich mit der Dynamik des technologischen Wandels. Die Analyse wird am konkreten Beispiel von e-Business Technologien durchgeführt. Dabei werden insbesondere die Konsequenzen von interdependenten Technologien untersucht. Es wird ge-zeigt, dass es zu steigenden Erträgen der Adoption kommen kann, wenn verwandte Technologien sich nicht in ih-ren Funktionalitäten substituieren. Dies kann zu einer endogenen Beschleunigung der technologischen Entwick-lung führen. Dies bedeutet, dass die Wahrscheinlichkeit der Adoption einer Technologie mit der Anzahl der zu-vor adoptierten, verwandten Technologien ansteigt. Diese Theorie wird empirisch getestet und in vier verschie-denen Untersuchungen mit zwei verschiedenen, großen Datensätzen bestätigt. Die Existenz einer wachsenden di-gitalen Kluft in der e-Business Technologie-Ausstattung der Unternehmen wird für den Zeitraum von 1994-2002 nachgewiesen. Außerdem wird argumentiert, dass die Adoption neuer Technologien in Firmen strategische Bedeutung hat da sich daraus Möglichkeiten zur Durchführung von Innovationen ergeben. Diese können sich entweder durch redu-zierte Produktionkosten für bestehende Produkte, neue Produkte und Dienstleistungen, oder neue Distributions-kanäle manifestieren. Empirische Evidenz zeigt, dass e-Business Technologien derzeit wichtige Enabler von In-novationen sind und dass innovative Firmen mit höherer Wahrscheinlichkeit wachsen. Außerdem wird gezeigt, dass durch e-Business Technologien induzierte Innovationen gegenüber anderen Innovationsarten nicht inferior sind in Bezug auf deren gleichzeitiges Auftreten mit finanziellen Leistungsindikatoren. Die Arbeit diskutiert die Implikationen dieser Ergebnisse aus volks- und betriebswirtschaftlicher Perspektive. / This dissertation primarily deals with two questions: First, what determines the process by which new tech-nologies spread among enterprises over time? Second, what are the consequences of the spread of new technolo-gies? Both questions concern the dynamics of technological change. They are analyzed considering the diffusion and implications of e-business technologies as a concrete example. Particular attention is given to technological interdependencies. It is shown that increasing returns to adoption can arise if related technologies do not substitute each other in their functionalities. This can lead to an endoge-nous acceleration of technological development. Hence, the probability to adopt any technology is an increasing function of previously adopted, related technologies. The theory is empirically tested and supported in four inde-pendent inquiries, using two different exceptionally large datasets and different econometric methods. The exis-tence of a growing digital divide among companies is demonstrated for the period between 1994 and 2002. In addition, it is argued that the adoption of new e-business technologies by firms has strategic relevance be-cause this creates opportunities to conduct innovation, either to reduce production costs for a given output, to create a new product or service, or to deliver products to customers in a way that is new to the enterprise. Empiri-cal evidence is presented showing that e-business technologies are currently an important enabler of innovations. It is found that innovative firms are more likely to grow. Also, e-business related innovations are not found to be inferior to traditional kinds of innovations in terms of simultaneous occurrence with superior financial perform-ance of enterprises. Implications of these findings are discussed both for economists and management researchers.