title: The effect of silane coupling agents on radiata pine fibre for use in thermoplastic matrix composites

authors: Pickering, Kim L.

subjects: A Thermoplastic resin

abstract: Gamma aminopropyltriethoxysilane (GS) and dichlorodiethylsilane (DCS) were employed for surface modification of radiata pine (Pinus radiata) wood fibre. Levels of fibre moisture were carefully controlled to optimise chemical and hydrogen bonding with these silane coupling agents. The effect of pre-treatment using 2% sodium hydroxide, shown to be effective in assisting silane coupling for other natural fibres [1], was also investigated. X-ray Photoelectron Spectroscopy (XPS) and Nuclear Magnetic Resonance (NMR) were used to characterise modification of the wood fibre. Concentrations of up to 3.2wt% Si were obtained on the fibre surface due to silane coupling, however, pre-treatment was found to dramatically reduce this value. NMR provided evidence that coupling had occurred between the fibre and DCS by a reaction producing ether linkages between the hydroxyl groups on the wood fibre and silane. Pre-treatment and treatment were found to have an insignificant effect on fibre strength. Composite sheets were produced by blending fibre (5, 10 and 20wt%) with polyethylene followed by extrusion. An increase in strength was obtained at fibre contents of 5wt% for all treatments compared to composites with untreated fibre. This is believed to be mainly due to increased compatibility of the fibre surface to polyethylene. However, there was no such improvement obtained at higher fibre contents. Evidence suggests that the production of voids is limiting composite strength.

text: The effect of silane coupling agents on radiata pine fibre for use in thermoplastic matrix composites Gamma aminopropyltriethoxysilane (GS) and dichlorodiethylsilane (DCS) were employed for surface modification of radiata pine (Pinus radiata) wood fibre. Levels of fibre moisture were carefully controlled to optimise chemical and hydrogen bonding with these silane coupling agents. The effect of pre-treatment using 2% sodium hydroxide, shown to be effective in assisting silane coupling for other natural fibres [1], was also investigated. X-ray Photoelectron Spectroscopy (XPS) and Nuclear Magnetic Resonance (NMR) were used to characterise modification of the wood fibre. Concentrations of up to 3.2wt% Si were obtained on the fibre surface due to silane coupling, however, pre-treatment was found to dramatically reduce this value. NMR provided evidence that coupling had occurred between the fibre and DCS by a reaction producing ether linkages between the hydroxyl groups on the wood fibre and silane. Pre-treatment and treatment were found to have an insignificant effect on fibre strength. Composite sheets were produced by blending fibre (5, 10 and 20wt%) with polyethylene followed by extrusion. An increase in strength was obtained at fibre contents of 5wt% for all treatments compared to composites with untreated fibre. This is believed to be mainly due to increased compatibility of the fibre surface to polyethylene. However, there was no such improvement obtained at higher fibre contents. Evidence suggests that the production of voids is limiting composite strength.

year: 2003

title: Jessica connects: A case study focussing on one child’s use of information and communication technology (ICT) in an early childhood education setting

authors: Archard, Sara

subjects: Information and Communication Technology (ICT)

abstract: Information and Communication Technology (ICT) is playing an ever increasing role in the lives of people which include young children; The role of ICT in early childhood educational services in Aotearoa New Zealand is still being argued despite curriculum, assessment and policy expectations that endorse and support its integration into practice. This chapter draws upon a small, qualitative case study involving young children and their uses of ICT in one early childhood education setting in Aotearoa New Zealand. A socio-cultural perspective has been used to recognise and examine the notion of children’s understanding and practices of ICT. In this chapter the focus is on Jessica, aged 4 years old, and the ways she uses ICT in her life as tool to document and share her learning and interests. These uses also reflect Jessica as a competent and confident learner using ICT as a cultural tool to mediate her learning in her home and early childhood education setting. The researchers examine the way ICT practices can contribute and fulfil curriculum and policy intentions that can support and endorse the competent, confident learner that reflects the curriculum principle of Empowerment. The chapter supports the view that ICT can be used to enhance the empowerment of the learner. We conclude that the early childhood curriculum and policy in Aotearoa New Zealand justifies the place of ICT in early childhood settings and should guide and inform teachers to use it as a valued learning and teaching tool. The researchers are of the opinion that the teachers have an active and collaborative role in responding to the needs of the 21st century learner to direct their own learning and that this can be guided by the curriculum aspirations in the principle of Empowerment.

text: Jessica connects: A case study focussing on one child’s use of information and communication technology (ICT) in an early childhood education setting Information and Communication Technology (ICT) is playing an ever increasing role in the lives of people which include young children; The role of ICT in early childhood educational services in Aotearoa New Zealand is still being argued despite curriculum, assessment and policy expectations that endorse and support its integration into practice. This chapter draws upon a small, qualitative case study involving young children and their uses of ICT in one early childhood education setting in Aotearoa New Zealand. A socio-cultural perspective has been used to recognise and examine the notion of children’s understanding and practices of ICT. In this chapter the focus is on Jessica, aged 4 years old, and the ways she uses ICT in her life as tool to document and share her learning and interests. These uses also reflect Jessica as a competent and confident learner using ICT as a cultural tool to mediate her learning in her home and early childhood education setting. The researchers examine the way ICT practices can contribute and fulfil curriculum and policy intentions that can support and endorse the competent, confident learner that reflects the curriculum principle of Empowerment. The chapter supports the view that ICT can be used to enhance the empowerment of the learner. We conclude that the early childhood curriculum and policy in Aotearoa New Zealand justifies the place of ICT in early childhood settings and should guide and inform teachers to use it as a valued learning and teaching tool. The researchers are of the opinion that the teachers have an active and collaborative role in responding to the needs of the 21st century learner to direct their own learning and that this can be guided by the curriculum aspirations in the principle of Empowerment.

year: 2016

title: Indigenous bodies: Ordinary lives

authors: Hokowhitu, Brendan

abstract: Ambivalence is the overwhelming feeling that haunts my relationship with physicality. Not only my body, but the bodies of an imagined multitude of Indigenous peoples dissected and made whole again via the violent synthesis of the colonial project. Like my own ambivalence (and by “ambivalence” I refer to simultaneous abhorrence and desire), the relationship between Indigenous peoples and physicality faces the anxiety of representation felt within Indigenous studies in general.

text: Indigenous bodies: Ordinary lives Ambivalence is the overwhelming feeling that haunts my relationship with physicality. Not only my body, but the bodies of an imagined multitude of Indigenous peoples dissected and made whole again via the violent synthesis of the colonial project. Like my own ambivalence (and by “ambivalence” I refer to simultaneous abhorrence and desire), the relationship between Indigenous peoples and physicality faces the anxiety of representation felt within Indigenous studies in general.

year: 2016