title: Microstructure and mechanical properties of TiAl alloys produced by rapid heating and open die forging of blended elemental powder compacts

authors: Su, Yongjun

subjects: TiAl alloy

abstract: Ti-43Al-5V-4Nb (at%) intermetallic compounds were fabricated by a rapid heating and open die forging method using blended elemental powders. The process route consisted of powder blending, compacting, rapid heating, open die forging and heat treatment. During heating there is porosity in the blended and warm compacted powder billets which still persists after the first forging. In order to remove this difficulty a two stage forging process was used. A fully lamellar structure was seen in the TiAl alloy after heat treatment. Overall, the TiAl alloy showed moderately good mechanical properties at room temperature and good mechanical properties, with reasonable strength and good ductility at high temperatures.

text: Microstructure and mechanical properties of TiAl alloys produced by rapid heating and open die forging of blended elemental powder compacts Ti-43Al-5V-4Nb (at%) intermetallic compounds were fabricated by a rapid heating and open die forging method using blended elemental powders. The process route consisted of powder blending, compacting, rapid heating, open die forging and heat treatment. During heating there is porosity in the blended and warm compacted powder billets which still persists after the first forging. In order to remove this difficulty a two stage forging process was used. A fully lamellar structure was seen in the TiAl alloy after heat treatment. Overall, the TiAl alloy showed moderately good mechanical properties at room temperature and good mechanical properties, with reasonable strength and good ductility at high temperatures.

year: 2013

title: Effect of previous handling experiences on responses of dairy calves to routine husbandry procedures

authors: Stewart, Mairi

subjects: dairy calves

abstract: The nature of human–animal interactions is an important factor contributing to animal welfare and productivity. Reducing stress during routine husbandry procedures is likely to improve animal welfare. We examined how the type of early handling of calves affected responses to two common husbandry procedures, ear-tagging and disbudding. Forty Holstein–Friesian calves (n = 20/treatment) were exposed to one of two handling treatments daily from 1 to 5 weeks of age: (1) positive (n = 20), involving gentle handling (soft voices, slow movements, patting), and (2) negative (n = 20), involving rough handling (rough voices, rapid movements, pushing). Heart rate (HR), respiration rate (RR) and behaviour (activity, tail flicking) were measured before and after ear-tagging and disbudding (2 days apart). Cortisol was measured at −20 (baseline), 20 and 40 min relative to disbudding time. There were no significant treatment differences in HR, RR or behaviour in response to either procedure. However, the following changes occurred across both treatment groups. HR increased after disbudding (by 14.7 ± 4.0 and 18.6 ± 3.8 bpm, positive and negative, respectively; mean ± s.e.m.) and ear-tagging (by 8.7 ± 3.1 and 10.3 ± 3.0 bpm, positive and negative, respectively). After disbudding, there was an increase in RR (by 8.2 ± 3.4 and 9.3 ± 3.4 breaths/min, positive and negative, respectively), overall activity (by 9.4 ± 1.2 and 9.9 ± 1.3 frequency/min, positive and negative, respectively) and tail flicking (by 13.2 ± 2.8 and 11.2 ± 3.0 frequency/min, positive and negative, respectively), and cortisol increased from baseline at 20 min post procedure (by 10.3 ± 1.1 and 12.3 ± 1.1 nmol/l positive and negative, respectively). Although we recorded significant changes in calf responses during ear-tagging and disbudding, the type of prior handling had no effect on responses. The effects of handling may have been overridden by the degree of pain and/or stress associated with the procedures. Further research is warranted to understand the welfare impact and interaction between previous handling and responses to husbandry procedures.

text: Effect of previous handling experiences on responses of dairy calves to routine husbandry procedures The nature of human–animal interactions is an important factor contributing to animal welfare and productivity. Reducing stress during routine husbandry procedures is likely to improve animal welfare. We examined how the type of early handling of calves affected responses to two common husbandry procedures, ear-tagging and disbudding. Forty Holstein–Friesian calves (n = 20/treatment) were exposed to one of two handling treatments daily from 1 to 5 weeks of age: (1) positive (n = 20), involving gentle handling (soft voices, slow movements, patting), and (2) negative (n = 20), involving rough handling (rough voices, rapid movements, pushing). Heart rate (HR), respiration rate (RR) and behaviour (activity, tail flicking) were measured before and after ear-tagging and disbudding (2 days apart). Cortisol was measured at −20 (baseline), 20 and 40 min relative to disbudding time. There were no significant treatment differences in HR, RR or behaviour in response to either procedure. However, the following changes occurred across both treatment groups. HR increased after disbudding (by 14.7 ± 4.0 and 18.6 ± 3.8 bpm, positive and negative, respectively; mean ± s.e.m.) and ear-tagging (by 8.7 ± 3.1 and 10.3 ± 3.0 bpm, positive and negative, respectively). After disbudding, there was an increase in RR (by 8.2 ± 3.4 and 9.3 ± 3.4 breaths/min, positive and negative, respectively), overall activity (by 9.4 ± 1.2 and 9.9 ± 1.3 frequency/min, positive and negative, respectively) and tail flicking (by 13.2 ± 2.8 and 11.2 ± 3.0 frequency/min, positive and negative, respectively), and cortisol increased from baseline at 20 min post procedure (by 10.3 ± 1.1 and 12.3 ± 1.1 nmol/l positive and negative, respectively). Although we recorded significant changes in calf responses during ear-tagging and disbudding, the type of prior handling had no effect on responses. The effects of handling may have been overridden by the degree of pain and/or stress associated with the procedures. Further research is warranted to understand the welfare impact and interaction between previous handling and responses to husbandry procedures.

year: 2013

title: Implications and opportunities for Maori land in the Rotorua catchment

authors: Tahana, Arapeta

abstract: Arapeta is the Portfolio Manager, Waiariki Region, at Te Tumu Paeroa. He works with Maori land owners to enable them to achieve higher aspirations for their land and assets. He also collaborates with a wide range of other people and organisations, from owners in Māori land blocks, to government agencies, private sector companies and experts in many fields to find innovative and pragmatic solutions to the challenges of growing Māori. He is an elected member on the Māori Advisory Committee to RDC working to develop a meaningful partnership between Te Arawa and the Council.

text: Implications and opportunities for Maori land in the Rotorua catchment Arapeta is the Portfolio Manager, Waiariki Region, at Te Tumu Paeroa. He works with Maori land owners to enable them to achieve higher aspirations for their land and assets. He also collaborates with a wide range of other people and organisations, from owners in Māori land blocks, to government agencies, private sector companies and experts in many fields to find innovative and pragmatic solutions to the challenges of growing Māori. He is an elected member on the Māori Advisory Committee to RDC working to develop a meaningful partnership between Te Arawa and the Council.

year: 2013