title: Significance of an early date from an adzed tree stump in Northland

authors: Higham, Thomas F.G.

abstract: Ogle, Jones, Sutton and Wallace (1998) have recently investigated the radiocarbon dating of a tree stump ('Ogle's stump’) which had evidence of adze marks, near the site of Taumatawhana pa, Houhora, Northland. The conventional radiocarbon age of 938 ± 31 BP was obtained at the Institute of Geological and Nuclear Sciences Ltd (formerly INS) laboratory in 1971. Ogle et al.(1998) considered the 'inbuilt age' of the wood (see McFadgen, 1982) and assessed its contribution to the radiocarbon determination. In this brief paper we re-evaluate that methodology and question the conclusion of Ogle et al. (1998) that the date is reliable. We are particularly concerned with the comparison of the date with an associated radiocarbon result obtained by Elliot et al. (1995) from a nearby site at Lake Taumatawhana, which we think is misleading.

text: Significance of an early date from an adzed tree stump in Northland Ogle, Jones, Sutton and Wallace (1998) have recently investigated the radiocarbon dating of a tree stump ('Ogle's stump’) which had evidence of adze marks, near the site of Taumatawhana pa, Houhora, Northland. The conventional radiocarbon age of 938 ± 31 BP was obtained at the Institute of Geological and Nuclear Sciences Ltd (formerly INS) laboratory in 1971. Ogle et al.(1998) considered the 'inbuilt age' of the wood (see McFadgen, 1982) and assessed its contribution to the radiocarbon determination. In this brief paper we re-evaluate that methodology and question the conclusion of Ogle et al. (1998) that the date is reliable. We are particularly concerned with the comparison of the date with an associated radiocarbon result obtained by Elliot et al. (1995) from a nearby site at Lake Taumatawhana, which we think is misleading.

year: 1998

title: A critical race analysis of Māori representation in university strategic documents in Aotearoa New Zealand

authors: Waitoki, Waikaremoana

subjects: critical race theory

abstract: Following the recent claims lodged at two universities in Aotearoa New Zealand alleging the existence of racism, there has been scepticism towards the professed commitments by universities to create an inclusive and safe environment for Indigenous Māori. As a Kaupapa Māori-informed study, we (a group of Māori and Tauiwi scholars) employed tenets of Critical Race Theory to examine how the representation of Māori is racialised and subordinated in university strategic documents. We located five predominant discourses portraying different mechanisms that reify whiteness in university practices such as the selective interpretation of Te Tiriti articles, targeted recruitment of Māori, framing of Māori as dependent on the Crown to succeed, commodification of mātauranga Māori, and avoidance of conversations about structural racism, colonisation, and racial equity. Our findings suggest that university strategic goal statements need to incorporate a critical race analysis, or else risk perpetuating practices that fall short of challenging the status quo.

text: A critical race analysis of Māori representation in university strategic documents in Aotearoa New Zealand Following the recent claims lodged at two universities in Aotearoa New Zealand alleging the existence of racism, there has been scepticism towards the professed commitments by universities to create an inclusive and safe environment for Indigenous Māori. As a Kaupapa Māori-informed study, we (a group of Māori and Tauiwi scholars) employed tenets of Critical Race Theory to examine how the representation of Māori is racialised and subordinated in university strategic documents. We located five predominant discourses portraying different mechanisms that reify whiteness in university practices such as the selective interpretation of Te Tiriti articles, targeted recruitment of Māori, framing of Māori as dependent on the Crown to succeed, commodification of mātauranga Māori, and avoidance of conversations about structural racism, colonisation, and racial equity. Our findings suggest that university strategic goal statements need to incorporate a critical race analysis, or else risk perpetuating practices that fall short of challenging the status quo.

year: 2024

title: Curing kinetics and effects of fibre surface treatment and curing parameters on the interfacial and tensile properties of hemp/epoxy composites

authors: Islam, Mohammad Saiful

subjects: hemp fibre

abstract: The curing kinetics of neat epoxy (NE) and hemp fibre/epoxy composites was studied and assessed using two dynamic models (the Kissinger and Flynn-Wall-Ozawa Models) and an isothermal model (the Autocatalytic Model) which was generally supported by the experimental data obtained from dynamic and isothermal differential scanning calorimetry (DSC) scans. The activation energies for the curing of composites exhibited lower values compared to curing of NE which is believed to be due to higher nucleophilic activity of the amine groups of the curing agent in the presence of fibres. The highest tensile strength, σ was obtained with composites produced with an epoxy to curing agent ratio of 1:1 and the highest Young's modulus, E was obtained with an epoxy to curing agent ratio of 1:1.2. Alkali treated hemp fibre/epoxy (ATFE) composites were found to have higher σ and E values compared to those for untreated hemp fibre/epoxy (UTFE) composites which was consistent with the trend for interfacial shear strength (IFSS) values. Composites σ and E were found to be higher for a processing temperature of 70°C than for 25°C for both UTFE and ATFE composites, but were found to decrease as the curing temperature was increased further to 120°C.

text: Curing kinetics and effects of fibre surface treatment and curing parameters on the interfacial and tensile properties of hemp/epoxy composites The curing kinetics of neat epoxy (NE) and hemp fibre/epoxy composites was studied and assessed using two dynamic models (the Kissinger and Flynn-Wall-Ozawa Models) and an isothermal model (the Autocatalytic Model) which was generally supported by the experimental data obtained from dynamic and isothermal differential scanning calorimetry (DSC) scans. The activation energies for the curing of composites exhibited lower values compared to curing of NE which is believed to be due to higher nucleophilic activity of the amine groups of the curing agent in the presence of fibres. The highest tensile strength, σ was obtained with composites produced with an epoxy to curing agent ratio of 1:1 and the highest Young's modulus, E was obtained with an epoxy to curing agent ratio of 1:1.2. Alkali treated hemp fibre/epoxy (ATFE) composites were found to have higher σ and E values compared to those for untreated hemp fibre/epoxy (UTFE) composites which was consistent with the trend for interfacial shear strength (IFSS) values. Composites σ and E were found to be higher for a processing temperature of 70°C than for 25°C for both UTFE and ATFE composites, but were found to decrease as the curing temperature was increased further to 120°C.

year: 2009