title: Microstructure and thermal stability of Al₂O₃-20vol%Fe₄₈Co₅₂ composite powder particles prepared by high energy mechanical milling

authors: Yusop, Masleeyati

subjects: High energy mechanical milling

abstract: High energy mechanical milling of a mixture of alumina and nanostructured Fe₄₈Co₅₂ powders was used in producing an Al₂O₃-20vol%Fe₄₈Co₅₂ composite powder. The milling time ranged from 8 to 48 hours. The microstructural changes were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis of the powder showed significant reduction in Al₂O₃ grain size after 24h milling to 27nm and approaching the alloy grain size with further milling. However, the alloy particles demonstrated almost unchanged grain size throughout the process. As milling progressed, changes of alloy particles shapes and their location in alumina phases became apparent. After 24h, a small fraction of Al₂O₃  particles became embedded into the alloy particles, forming a complex composite structure. Small change in the microhardness of the particles was observed. It was also observed that the Fe₄₈Co₅₂ particles and Al₂O₃  matrix reacted heavily when the powder was heated to 10500°C.

text: Microstructure and thermal stability of Al₂O₃-20vol%Fe₄₈Co₅₂ composite powder particles prepared by high energy mechanical milling High energy mechanical milling of a mixture of alumina and nanostructured Fe₄₈Co₅₂ powders was used in producing an Al₂O₃-20vol%Fe₄₈Co₅₂ composite powder. The milling time ranged from 8 to 48 hours. The microstructural changes were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis of the powder showed significant reduction in Al₂O₃ grain size after 24h milling to 27nm and approaching the alloy grain size with further milling. However, the alloy particles demonstrated almost unchanged grain size throughout the process. As milling progressed, changes of alloy particles shapes and their location in alumina phases became apparent. After 24h, a small fraction of Al₂O₃  particles became embedded into the alloy particles, forming a complex composite structure. Small change in the microhardness of the particles was observed. It was also observed that the Fe₄₈Co₅₂ particles and Al₂O₃  matrix reacted heavily when the powder was heated to 10500°C.

year: 2009

title: The Bispectral Index: A measure of depth of sleep?

authors: Sleigh, James W.

subjects: BIS

abstract: How does physiological sleep affect the Bispectral Index (BIS)? We collected electroencephalographic (EEG) data from five subjects during the early part of the night, comparing the changes in the BIS with the conventional EEG stages of sleep. We found that the BIS was a consistent marker of depth of sleep. Light sleep occurred at BIS values of 75–90, slow-wave sleep occurred at BIS values of 20–70, and rapid eye movement sleep occurred at BIS values of 75–92. The effects of natural sleep on the BIS seem to be similar to the effects of general anesthesia on the BIS. The BIS may have a role in monitoring depth of sleep. Implications: Electroencephalographic data were collected from five subjects during sleep. We found that the Bispectral Index decreased during increasing depth of sleep in a fashion very similar to the decrease in Bispectral Index that occurs during general anesthesia. This study further highlights the electroencephalographic similarities of states of sleep and general anesthesia.

text: The Bispectral Index: A measure of depth of sleep? How does physiological sleep affect the Bispectral Index (BIS)? We collected electroencephalographic (EEG) data from five subjects during the early part of the night, comparing the changes in the BIS with the conventional EEG stages of sleep. We found that the BIS was a consistent marker of depth of sleep. Light sleep occurred at BIS values of 75–90, slow-wave sleep occurred at BIS values of 20–70, and rapid eye movement sleep occurred at BIS values of 75–92. The effects of natural sleep on the BIS seem to be similar to the effects of general anesthesia on the BIS. The BIS may have a role in monitoring depth of sleep. Implications: Electroencephalographic data were collected from five subjects during sleep. We found that the Bispectral Index decreased during increasing depth of sleep in a fashion very similar to the decrease in Bispectral Index that occurs during general anesthesia. This study further highlights the electroencephalographic similarities of states of sleep and general anesthesia.

year: 1999

title: 'Te Kawau Mārō' The Role of Media in Revitalising Te Reo Māori

authors: Hill, Jessie Lee Anahira

subjects: Media

abstract: The intent of this thesis is to investigate the role media plays in relation to the revitalisation of te reo Māori in Aotearoa/New Zealand society. This is essential as the media's latent potential is often underestimated and therefore underutilised. 

For Māori and inevitably te reo Māori, media has been a topic of heated contestation for over a century. It is postulated that throughout this troubled history, media's influence has contributed to an erosion of te reo Māori and then conversely, since the late 20th century, its attempted revival. The journey of te reo Māori from past to present may be likened to a voyage of a traditional 'waka hourua' (voyaging or double hulled canoe). 'Nga ngaru e toru' ('three waves') illustrates the three stages that I have defined as catalysts significantly impacting te reo Māori. 

Grounded firmly in a Kaupapa Māori methodological and theoretical framework based on careful research and intimate cultural knowledge, my innovative approaches to language revitalisation entitled the Tapatoru (triangle) Model 1 and Tapatoru Model 2 will be introduced and explained. These distinct language revitalisation paradigms illustrate the core ingredients needed in effective language revival and illustrate the positioning and function of the media within these strategic models.

text: 'Te Kawau Mārō' The Role of Media in Revitalising Te Reo Māori The intent of this thesis is to investigate the role media plays in relation to the revitalisation of te reo Māori in Aotearoa/New Zealand society. This is essential as the media's latent potential is often underestimated and therefore underutilised. 

For Māori and inevitably te reo Māori, media has been a topic of heated contestation for over a century. It is postulated that throughout this troubled history, media's influence has contributed to an erosion of te reo Māori and then conversely, since the late 20th century, its attempted revival. The journey of te reo Māori from past to present may be likened to a voyage of a traditional 'waka hourua' (voyaging or double hulled canoe). 'Nga ngaru e toru' ('three waves') illustrates the three stages that I have defined as catalysts significantly impacting te reo Māori. 

Grounded firmly in a Kaupapa Māori methodological and theoretical framework based on careful research and intimate cultural knowledge, my innovative approaches to language revitalisation entitled the Tapatoru (triangle) Model 1 and Tapatoru Model 2 will be introduced and explained. These distinct language revitalisation paradigms illustrate the core ingredients needed in effective language revival and illustrate the positioning and function of the media within these strategic models.

year: 2010