title: Yield of annealing on the properties of the Ti-5Al-2.5Fe alloy produced by Powder Forging

authors: Jia, Mingtu

abstract: The high cost of titanium alloys can be reduced using alternative manufacturing techniques and using cheap alloying elements. In this study, the Ti-5Al-2.5Fe alloy, a cheaper α + β alloy than the workhorse Ti-6Al-4V, was produced by powder metallurgy combined with hot thermomechanical deformation by means of forging. The forged alloy was subsequently subjected to a heat treatment at 750 °C for several annealing times in order to modify the microstructure and tailor the mechanical properties. This study demonstrates that, regardless of the forging temperature used, annealing of the forged Ti-5Al-2.5Fe alloy improves both the strength and the ductility. Generally, the longer the annealing time, the higher the gain in strength and ductility with respect to the forged alloy. Moreover, annealing is significantly more beneficial to improve the ductility rather than the strength of the powder-forged Ti-5Al-2.5Fe alloy.

text: Yield of annealing on the properties of the Ti-5Al-2.5Fe alloy produced by Powder Forging The high cost of titanium alloys can be reduced using alternative manufacturing techniques and using cheap alloying elements. In this study, the Ti-5Al-2.5Fe alloy, a cheaper α + β alloy than the workhorse Ti-6Al-4V, was produced by powder metallurgy combined with hot thermomechanical deformation by means of forging. The forged alloy was subsequently subjected to a heat treatment at 750 °C for several annealing times in order to modify the microstructure and tailor the mechanical properties. This study demonstrates that, regardless of the forging temperature used, annealing of the forged Ti-5Al-2.5Fe alloy improves both the strength and the ductility. Generally, the longer the annealing time, the higher the gain in strength and ductility with respect to the forged alloy. Moreover, annealing is significantly more beneficial to improve the ductility rather than the strength of the powder-forged Ti-5Al-2.5Fe alloy.

year: 2023

title: Tree encroachment may lead to functionally-significant changes in peatland testate amoeba communities

authors: Payne, Richard J.

subjects: Science & Technology

abstract: Climate change is likely to cause increased tree recruitment on open peatlands but we currently have little idea what consequences this vegetation change may have below-ground. Here we use transects across forested to open bog ecotones at three Russian peatland complexes to assess potential changes in the most abundant group of peatland protists – the testate amoebae. We show that the testate amoeba communities of forested and open bog are markedly different with a very abrupt boundary at, or near, the vegetation ecotone. Changes along our transects suggest that tree encroachment may reduce the trophic level of testate amoeba communities and reduce the contribution of mixotrophic testate amoebae to primary production. Our study strongly suggests that increased tree recruitment on open peatlands will have important consequences for both microbial biodiversity and microbially-mediated ecosystem processes.

text: Tree encroachment may lead to functionally-significant changes in peatland testate amoeba communities Climate change is likely to cause increased tree recruitment on open peatlands but we currently have little idea what consequences this vegetation change may have below-ground. Here we use transects across forested to open bog ecotones at three Russian peatland complexes to assess potential changes in the most abundant group of peatland protists – the testate amoebae. We show that the testate amoeba communities of forested and open bog are markedly different with a very abrupt boundary at, or near, the vegetation ecotone. Changes along our transects suggest that tree encroachment may reduce the trophic level of testate amoeba communities and reduce the contribution of mixotrophic testate amoebae to primary production. Our study strongly suggests that increased tree recruitment on open peatlands will have important consequences for both microbial biodiversity and microbially-mediated ecosystem processes.

year: 2016

title: Weaving kaupapa Māori and e-Learning

authors: Neal, Terry

subjects: New Zealand

abstract: This paper describes the creation and design of an online professional development course that aims to help educators in New Zealand to weave kaupapa Māori and e-Learning approaches together. The team sought to model weaving of kaupapa Māori and e-Learning approaches in how they worked together and the educational design for the material. The authors propose that educators with these skills are crucial if we are to effectively meet the needs of Māori learners, more than that, of all New Zealand learners, in the 21st century.

text: Weaving kaupapa Māori and e-Learning This paper describes the creation and design of an online professional development course that aims to help educators in New Zealand to weave kaupapa Māori and e-Learning approaches together. The team sought to model weaving of kaupapa Māori and e-Learning approaches in how they worked together and the educational design for the material. The authors propose that educators with these skills are crucial if we are to effectively meet the needs of Māori learners, more than that, of all New Zealand learners, in the 21st century.

year: 2006-09