title: Equilibrium moisture content of radiata pine at elevated temperature and pressure reveals measurement challenges

authors: Pearson, Hamish

subjects: water-vapor

abstract: Relatively few studies have been performed on the equilibrium moisture content (EMC) of wood under conditions of elevated temperature and pressure. Eight studies indicated that EMC near saturation decreased between 100 and 150 A degrees C, whilst five studies indicated that EMC increased. The aim of this study was to identify the likely source of the disagreement using radiata pine (Pinus radiata D. Don) sapwood which was conditioned to a moisture content of around 3 % and then exposed for 1 h at 150 A degrees C and relative humidities of either 50, 70 or 90 %. Mean values of EMC, obtained through in situ gravimetric analyses, were 5.7, 7.6 and 12.6 % with 95 % confidence intervals of the order of 1 %. In two further experiments, the humidity was allowed to rise briefly above 90 % and the moisture content after 1 h was found to be > 30 % as in the five studies that indicated EMC increased above 100 A degrees C. The high moisture contents were attributed to condensation of liquid water on the specimen with subsequent evaporation at a rate that was too slow for the moisture content to reach equilibrium before it was measured. Reliable EMC data at elevated temperatures require (1) tight process control of experimental conditions with minimal standard error, (2) specimens with low initial moisture content to avoid unwanted wood mass loss over time, (3) a relative humidity upper limit that avoids drift above 95 %, and (4) extrapolation of data to humidity approaching 100 %.

text: Equilibrium moisture content of radiata pine at elevated temperature and pressure reveals measurement challenges Relatively few studies have been performed on the equilibrium moisture content (EMC) of wood under conditions of elevated temperature and pressure. Eight studies indicated that EMC near saturation decreased between 100 and 150 A degrees C, whilst five studies indicated that EMC increased. The aim of this study was to identify the likely source of the disagreement using radiata pine (Pinus radiata D. Don) sapwood which was conditioned to a moisture content of around 3 % and then exposed for 1 h at 150 A degrees C and relative humidities of either 50, 70 or 90 %. Mean values of EMC, obtained through in situ gravimetric analyses, were 5.7, 7.6 and 12.6 % with 95 % confidence intervals of the order of 1 %. In two further experiments, the humidity was allowed to rise briefly above 90 % and the moisture content after 1 h was found to be > 30 % as in the five studies that indicated EMC increased above 100 A degrees C. The high moisture contents were attributed to condensation of liquid water on the specimen with subsequent evaporation at a rate that was too slow for the moisture content to reach equilibrium before it was measured. Reliable EMC data at elevated temperatures require (1) tight process control of experimental conditions with minimal standard error, (2) specimens with low initial moisture content to avoid unwanted wood mass loss over time, (3) a relative humidity upper limit that avoids drift above 95 %, and (4) extrapolation of data to humidity approaching 100 %.

year: 2013

title: PBRF on the horizon

authors: Smith, Ron C.

subjects: PBRF

abstract: New Zealand universities spend a great deal of time and money evaluating the research outputs of their staff in the cause of Performance Based Research Funding (PBRF).  This time and money is wasted since the assumptions that lie behind this process are fatally flawed and the results are neither valid nor fair.  Additionally PBRF is inconsistent with the universities’ obligations to be ‘critic and conscience’ for society and to scholarship, itself.  The paper argues that no further assessments of this kind should be undertaken.

text: PBRF on the horizon New Zealand universities spend a great deal of time and money evaluating the research outputs of their staff in the cause of Performance Based Research Funding (PBRF).  This time and money is wasted since the assumptions that lie behind this process are fatally flawed and the results are neither valid nor fair.  Additionally PBRF is inconsistent with the universities’ obligations to be ‘critic and conscience’ for society and to scholarship, itself.  The paper argues that no further assessments of this kind should be undertaken.

year: 2008-09-13

title: Gendered geographies of resistance, resilience and reworking in Aotearoa feminist geography scholarship

authors: Adams-Hutcheson, Gail

abstract: Aotearoa New Zealand feminist geographies involve alliances of connected and vibrant researchers who pay close attention to the politics of knowledge production, power, intersectionality and decolonisation. Safe spaces to speak and write together have been nurtured over time ‘down under’ due to a collective politics of care and mentoring. This special issue demonstrates the strength of collective thinking on resistance, resilience and reworking contemporary geographical practice in Aotearoa. The four empirically based and theoretically informed articles develop new thinking about resistance to colonialism, patriarchy, racism, metricisation and oppression. These critical articles contribute to feminist geographical knowledges both locally and globally.

text: Gendered geographies of resistance, resilience and reworking in Aotearoa feminist geography scholarship Aotearoa New Zealand feminist geographies involve alliances of connected and vibrant researchers who pay close attention to the politics of knowledge production, power, intersectionality and decolonisation. Safe spaces to speak and write together have been nurtured over time ‘down under’ due to a collective politics of care and mentoring. This special issue demonstrates the strength of collective thinking on resistance, resilience and reworking contemporary geographical practice in Aotearoa. The four empirically based and theoretically informed articles develop new thinking about resistance to colonialism, patriarchy, racism, metricisation and oppression. These critical articles contribute to feminist geographical knowledges both locally and globally.

year: 2022-11-22