Wear Resistant Polydopamine/PTFE Nanoparticle Composite Coating for Dry Lubrication Applications

This dissertation presents an investigation into the effect of nanoparticle fillers and a polydopamine adhesive primer on the tribological performance of thin PTFE films. The principal objective of this investigation was to reduce wear in PTFE films, an issue which precludes the use of PTFE films in tribological applications requiring high durability. The friction and wear of the composite films were evaluated using a ball-on-flat configuration in linear reciprocating motion. It was found that the use of a polydopamine adhesive primer reduces the wear of PTFE films more than 600 times. X-ray photoelectron spectroscopy (XPS) results show that a tenacious layer of PTFE remains adhered to the polydopamine primer, which enables the durability of the polydopamine/PTFE film. Furthermore, the combination of a polydopamine primer, Cu nanoparticle fillers in the PTFE film, and optimal fabrication processes provided a collective effect that increased the wear life of PTFE films by more than 940 times. Because of the relatively low thickness of the film, it shows great potential for use in applications where durable, thin films are desirable

Social structural change in the English-speaking Caribbean

Includes bibliographyEstudia algunos aspectos de las tendencias dominantes en la sociedad de las Indias Occidentales en las últimas décadas. Analiza el marco social, la evolución y estructura de la economía, cambios y consecuencias en las condiciones económicas, políticas y demográficas; pronósticos

Chinese Immigrant Parents’ Communication with School Teachers

Parent-teacher communication has great influence on children’s school performance. Using Walker et al.’s model of parent involvement as a theoretical framework, this study investigated Chinese immigrant parents’ communication experience with teachers and the psychological factors that influenced such communication. The study collected data through survey and revealed that Chinese immigrant parents recognized their responsibility to maintain regular communication with school teachers and believed that such communication could bring beneficial outcomes to their children’s education. The study found that Chinese immigrant parents had more frequent communication with teachers than those recorded in previous literatures. Among the five psychological factors, communication self-efficacy seems to have the strongest relation with parents’ communication behaviors

Being Tamil, being Hindu:Tamil migrants’ negotiations of the absence of Tamil Hindu spaces in the West Midlands and South West of England

This paper considers the religious practices of Tamil Hindus who have settled in the West Midlands and South West of England in order to explore how devotees of a specific ethno-regional Hindu tradition with a well-established UK infrastructure in the site of its adherents’ population density adapt their religious practices in settlement areas which lack this infrastructure. Unlike the majority of the UK Tamil population who live in the London area, the participants in this study did not have ready access to an ethno-religious infrastructure of Tamil-orientated temples and public rituals. The paper examines two means by which this absence was addressed as well as the intersections and negotiations of religion and ethnicity these entailed: firstly, Tamil Hindus’ attendance of temples in their local area which are orientated towards a broadly imagined Hindu constituency or which cater to a non-Tamil ethno-linguistic or sectarian community; and, secondly, through the ‘DIY’ performance of ethnicised Hindu ritual in non-institutional settings

Toward an Appropriate Theoretical Framework for Agricultural Development Planning and Policy

In order to be elective, development planning and policy need to be in- formed by relevant theory. This paper at first argues that, in many important respects, the current body of agricultural development theory inadequately represents the Caribbean situation. In so far as this hypothesis is correct, it implicitly provides a partial explanation for the failure to get agriculture moving in spite of substantial government intervention and assistance in most territories of the region. It also sets the stage for the second objective of the paper: to outline some of the steps required for developing an appropriate theoretical framework and to place this selection of papers in the perspective of these considerations

Polítical economy of agricultural and rural sector planning in Caribbean societies

Incluye Bibliografí

Persistent Poverty: Underdevelopment in Plantation Ekonomies of the Third World

xxvii, 303 hlm.; 21 cm