Epoxy resin chamber for high voltage breakdown studies in high vacuum

As the study of electrical breakdown phenomena in vacuum systems, gains more importance, a thorough understanding of the breakdown mechanism at high voltages necessitates a chamber for experimental studies. An epoxy-resin chamber has been constructed by casting ring sections which were joined together. The advantages of such a chamber over the conventional metal or glass chamber are given especially as regards the electric field configuration, high voltage lead-in, and the ease of construction. Special facilities can be incorporated while constructing the chamber which makes it more versatile; for example, in pre-breakdown current measurements, electron beam focusing studies, etc.

Breakdown in p‐n junction diodes made on polycrystalline silicon of large grain size

This communication describes the voltage‐current characteristics in the breakdown region of p‐n junctions made on polycrystalline silicon of large grain size. The observed soft breakdown characteristics have been explained by taking into account the effect of curvature of the junction near the grain boundaries.

Analysis of effects of ambients (temperature and light intensity) on the electrical breakdown in bipolar transistors

This paper presents an analysis of the effects of ambients-temperature and light intensity on the V-l characteristics of bipolar transistors under electrical breakdown. The analysis is based on the transportation and storage of majority carriers in the base region. It is shown that this analysis can explain the observed shift in the V-l characteristics to lower voltages with increase in either temperature or light intensity.

Doing marriage and parenthood: The division of household labour across two life course events

The current study is a longitudinal investigation into changes in the division of household labour across transitions to marriage and parenthood in the UK. Previous research has noted a more traditional division of household labour, with women performing the majority of housework, amongst spouses and couples with children. However, the bulk of this work has been cross-sectional in nature. The few longitudinal studies that have been carried out have been rather ambiguous about the effect of marriage and parenthood on the division of housework. Theoretically, this study draws on gender construction theory. The key premise of this theory is that gender is something that is performed and created in interaction, and, as a result, something fluid and flexible rather than fixed and stable. The idea that couples 'do gender' through housework has been a major theoretical breakthrough. Gender-neutral explanations of the division of household labour, positing rational acting individuals, have failed to explicate why women continue to perform an unequal share of housework, regardless of socioeconomic status. Contrastingly, gender construction theory situates gender as the key process in dividing household labour. By performing and avoiding certain housework chores, couples fulfill social norms of what it means to be a man and a woman although, given the emphasis on human agency in producing and contesting gender, couples are able to negotiate alternative gender roles which, in turn, feed back into the structure of social norms in an ever-changing societal landscape. This study adds extra depth to the doing gender approach by testing whether or not couples negotiate specific conjugal and parent roles in terms of the division of household labour. Both transitions hypothesise a more traditional division of household labour. Data comes from the British Household Panel Survey, a large, nationally representative quantitative survey that has been carried out annually since 1991. Here, data tracks the same 776 couples at two separate time points - 1996 and 2005. OLS regression is used to test whether or not transitions to marriage and parenthood have a significant impact on the division of household labour whilst controlling for host of relevant socio-economic factors. Results indicate that marriage has no significant effect on how couples partition housework. Those couples making the transition from cohabitation to marriage do not show significant changes in housework arrangements from those couples who remain cohabiting in both waves. On the other hand, becoming parents does lead to a more traditional division of household labour whilst controlling for socio-economic factors which accompany the move to parenthood. There is then some evidence that couples use the site of household labour to 'do parenthood' and generate identities which both use and inform socially prescribed notions of what it means to be a mother and a father. Support for socio-economic explanations of the division of household labour was mixed although it remains clear that they, alone, cannot explain how households divide housework.

Cross-field gas breakdown in a coaxial cylinder geometry

Sparking potentials in a coaxial cylinder geometry in oxygen and dry air were measured in crossed electric and magnetic fields. From the data effective collision frequencies were calculated using the equivalent pressure concept. It is shown that the equivalent pressure concept holds good for deriving the effective collision frequencies in non-uniform electric fields.

Choosing the Arranged One, Arranging the Chosen One – Imagining an Indian Modernity: Reconciling Love, Marriage and Family On and Off the Screen

This is a study on the changing practices of kinship in Northern India. The change in kinship arrangements, and particularly in intermarriage processes, is traced by analysing the reception of Hindi popular cinema. Films and their role and meaning in people´s lives in India was the object of my research. Films also provided me with a methodology for approaching my other subject-matters: family, marriage and love. Through my discussion of cultural change, the persistence of family as a core value and locus of identity, and the movie discourses depicting this dialogue, I have looked for a possibility of compromise and reconciliation in an Indian context. As the primary form of Indian public culture, cinema has the ability to take part in discourses about Indian identity and cultural change, and alleviate the conflicts that emerge within these discourses. Hindi popular films do this, I argue, by incorporating different familiar cultural narratives in a resourceful way, thus creating something new out of the old elements. The final word, however, is the one of the spectator. The “new” must come from within the culture. The Indian modernity must be imaginable and distinctively Indian. The social imagination is not a “Wild West” where new ideas enter the void and start living a life of their own. The way the young women in Dehra Dun interpreted family dramas and romantic movies highlights the importance of family and continuity in kinship arrangements. The institution of arranged marriage has changed its appearance and gained new alternative modes such as love cum arranged marriage. It nevertheless remains arranged by the parents. In my thesis I have offered a social description of a cultural reality in which movies act as a built-in part. Movies do not work as a distinct realm, but instead intertwine with the social realities of people as a part of a continuum. The social imagination is rooted in the everyday realities of people, as are the movies, in an ontological and categorical sense. According to my research, the links between imagination and social life were not so much what Arjun Appadurai would call global and deterritorialised, but instead local and conventional.

AC breakdown characteristics of epoxy alumina nanocomposites

Experiments were conducted to measure the ac breakdown strength of 0.5 mm, thick epoxy alumina nanocomposites with different filler concentrations of 0.1, 1 and 5wt%. The experiments were performed as per the ASTM D 149 standard. It was observed that the ac breakdown strength was marginally lower up to 1wt% filler concentration and then increased at 5wt% filler concentration as compared to the unfilled epoxy. The Weibull shape parameter (β) increased with the addition of nanoparticles to epoxy. The dependence of thickness on the ac breakdown strength was also analyzed by conducting experiments on 1mm and 3mm thick unfilled epoxy and epoxy alumina nanocomposites of 1wt% and 5wt% filler concentrations. The DSC analysis was done to understand the material properties at the filler resin interface in order to study the effect of the filler concentration and thereby the influence of the interface on the ac breakdown strength of epoxy nanocomposites.

Trends in consanguineous marriage in Karnataka, South India, 1980–89

Analysis of data on 106,848 marriages in the cities of Bangalore and Mysore, South India, between 1980 and 1989 showed that levels of consanguineous marriage varied between cities through time and by religion. The average coefficient of inbreeding was higher in Bangalore (F = 0·0339) than in Mysore (F = 0·0203), principally reflecting large-scale, post-Independence rural migration into Bangalore. Although there was some evidence of a decline in consanguineous marriages in Mysore, there was no convincing support in either city for earlier projections of a rapid reduction in the popularity of unions between close biological relatives.

AC Breakdown Characteristics of Epoxy Nanocomposites

Experiments were conducted to measure the ac breakdown strength of epoxy alumina nanocomposites with different filler loadings of 0.1, 1 and 5 wt%. The experiments were performed as per the ASTM D 149 standard on samples of thickness 0.5 mm, 1 mm and 3 mm in order to study the effect of thickness on the ac breakdown strength of epoxy nanocomposites. In the case of epoxy alumina nanocomposites it was observed that the ac breakdown strength was marginally lower for 0.1 wt% and 1 wt% filler loadings and then increased at 5 wt% filler loading as compared to the unfilled epoxy. The Weibull shape parameter (beta) increased with the addition of nanoparticles to epoxy as well as with the increasing sample thickness for all the filler loadings considered. DSC analysis was done to study the material properties at the filler resin interface in order to understand the effect of the filler loading and thereby the influence of the interface on the ac breakdown strength of epoxy nanocomposites. It was also observed that the decrease in ac electric breakdown strength with an increase in sample thickness follows an inverse power-law dependence. In addition, the ac breakdown strength of epoxy silica nanocomposites have also been studied in order to understand the influence of the filler type on the breakdown strength.