title: Characterizing the cleaning process of chicken feathers.

authors: Sudalaiyandi, Ganesh

subjects: cleaning

abstract: Recently, there has been a surge in investigating the potential of using natural fibers for reinforcements in composite materials. One such natural fiber having immense potential for use in polymer composites is chicken feather fiber. Every year, over 4.8 million tonnes of chicken feathers are generated globally. Currently, feathers are hydrolyzed into feather-meal which is used as an animal feed and fertilizer. Chicken feathers are cheap, abundant and easily available. These feathers could be used as reinforcements in polymer composites. But, the feathers obtained from meat processing plants are coated with blood, offal fat, preen oil, debris and poultry processing water. This makes the feathers sticky, odoriferous and unfit for use as reinforcement. Extracting lipids from the feathers by leaching results in fibers which are not greasy and improves the fiber-matrix bonding of composites.

The objective of this study was to characterize the cleaning process of chicken feather fibers. Also, the effect of hydrogen peroxide cleaning on the mechanical properties of feather fiber was tested. The raw feathers were decontaminated with sodium hypochlorite and these samples were used for the cleaning experiments. Cleaning was carried out using 0.15 % and 0.25% of H₂O₂. Stages of cleaning and time were varied. The sample to solvent ratio was 10g/500 ml of solvent. It was found that 10 minutes of leaching for 3 stages was efficient in extracting soluble impurities from the feathers. Equilibrium experiments were conducted and a mass balance based on lipid exchange was designed. An equilibrium graph was plotted. Also, single fiber tensile tests were done on the H₂O₂ treated samples. A two parameter Weibull distribution was plotted to predict the failure strength of the fibers. It was found that H₂O₂ treatment on feathers reduces its Tensile strength (by very less magnitude). It was also observed that fibers were not damaged due to H₂O₂ treatment.

text: Characterizing the cleaning process of chicken feathers. Recently, there has been a surge in investigating the potential of using natural fibers for reinforcements in composite materials. One such natural fiber having immense potential for use in polymer composites is chicken feather fiber. Every year, over 4.8 million tonnes of chicken feathers are generated globally. Currently, feathers are hydrolyzed into feather-meal which is used as an animal feed and fertilizer. Chicken feathers are cheap, abundant and easily available. These feathers could be used as reinforcements in polymer composites. But, the feathers obtained from meat processing plants are coated with blood, offal fat, preen oil, debris and poultry processing water. This makes the feathers sticky, odoriferous and unfit for use as reinforcement. Extracting lipids from the feathers by leaching results in fibers which are not greasy and improves the fiber-matrix bonding of composites.

The objective of this study was to characterize the cleaning process of chicken feather fibers. Also, the effect of hydrogen peroxide cleaning on the mechanical properties of feather fiber was tested. The raw feathers were decontaminated with sodium hypochlorite and these samples were used for the cleaning experiments. Cleaning was carried out using 0.15 % and 0.25% of H₂O₂. Stages of cleaning and time were varied. The sample to solvent ratio was 10g/500 ml of solvent. It was found that 10 minutes of leaching for 3 stages was efficient in extracting soluble impurities from the feathers. Equilibrium experiments were conducted and a mass balance based on lipid exchange was designed. An equilibrium graph was plotted. Also, single fiber tensile tests were done on the H₂O₂ treated samples. A two parameter Weibull distribution was plotted to predict the failure strength of the fibers. It was found that H₂O₂ treatment on feathers reduces its Tensile strength (by very less magnitude). It was also observed that fibers were not damaged due to H₂O₂ treatment.

year: 2012

title: Effect of grazing on ship rat density in forest fragments of lowland Waikato, New Zealand

authors: Innes, John G.

subjects: fencing

abstract: Ship rat (Rattus rattus) density was assessed by snap-trapping during summer and autumn in eight indigenous forest fragments (mean 5 ha) in rural landscapes of Waikato, a lowland pastoral farming district of the North Island, New Zealand. Four of the eight were fenced and four grazed. In each set of four, half were connected with hedgerows, gullies or some other vegetative corridor to nearby forest and half were completely isolated. Summer rat density based on the number trapped in the first six nights was higher in fenced (mean 6.5 rats ha–1) than in grazed fragments (mean 0.5 rats ha–1; P = 0.02). Rats were eradicated (no rats caught and no rat footprints recorded for three consecutive nights) from all eight fragments in January–April 2008, but reinvaded within a month; time to eradication averaged 47 nights in fenced and 19 nights in grazed fragments. A second six-night trapping operation in autumn, 1–3 months after eradication, found no effect of fencing (P = 0.73). Connectedness to an adjacent source of immigrants did not influence rat density within a fragment in either season (summer P = 0.25, autumn P = 0.67). An uncalibrated, rapid (one-night) index of ship rat density, using baited tracking tunnels set in a 50 × 50 m grid, showed a promising relationship with the number of rats killed per hectare over the first six nights, up to tracking index values of c. 30% (corresponding to c. 3–5 rats ha–1). The index will enable managers to determine if rat abundance is low enough to achieve conservation benefits. Our results confirm a dilemma for conservation in forest fragments. Fencing protects vegetation, litter and associated ecological processes, but also increases number of ship rats, which destroy seeds, invertebrates and nesting birds. Maximising the biodiversity values of forest fragments therefore requires both fencing and control of ship rats.

text: Effect of grazing on ship rat density in forest fragments of lowland Waikato, New Zealand Ship rat (Rattus rattus) density was assessed by snap-trapping during summer and autumn in eight indigenous forest fragments (mean 5 ha) in rural landscapes of Waikato, a lowland pastoral farming district of the North Island, New Zealand. Four of the eight were fenced and four grazed. In each set of four, half were connected with hedgerows, gullies or some other vegetative corridor to nearby forest and half were completely isolated. Summer rat density based on the number trapped in the first six nights was higher in fenced (mean 6.5 rats ha–1) than in grazed fragments (mean 0.5 rats ha–1; P = 0.02). Rats were eradicated (no rats caught and no rat footprints recorded for three consecutive nights) from all eight fragments in January–April 2008, but reinvaded within a month; time to eradication averaged 47 nights in fenced and 19 nights in grazed fragments. A second six-night trapping operation in autumn, 1–3 months after eradication, found no effect of fencing (P = 0.73). Connectedness to an adjacent source of immigrants did not influence rat density within a fragment in either season (summer P = 0.25, autumn P = 0.67). An uncalibrated, rapid (one-night) index of ship rat density, using baited tracking tunnels set in a 50 × 50 m grid, showed a promising relationship with the number of rats killed per hectare over the first six nights, up to tracking index values of c. 30% (corresponding to c. 3–5 rats ha–1). The index will enable managers to determine if rat abundance is low enough to achieve conservation benefits. Our results confirm a dilemma for conservation in forest fragments. Fencing protects vegetation, litter and associated ecological processes, but also increases number of ship rats, which destroy seeds, invertebrates and nesting birds. Maximising the biodiversity values of forest fragments therefore requires both fencing and control of ship rats.

year: 2010

title: Māori Waiata: Discourse structuring, sub-genres and aesthetics

authors: Roa, Raukura

subjects: Te reo Māori

abstract: With particular reference to a discourse-based analysis of five waiata tangi from Ngāti Hauā, it is argued here that different types of Māori waiata (songs and chants) may be characterised by different types of overall discourse structuring. It is also suggested that discourse structuring may be a significant aspect of the aesthetics of Māori waiata.

text: Māori Waiata: Discourse structuring, sub-genres and aesthetics With particular reference to a discourse-based analysis of five waiata tangi from Ngāti Hauā, it is argued here that different types of Māori waiata (songs and chants) may be characterised by different types of overall discourse structuring. It is also suggested that discourse structuring may be a significant aspect of the aesthetics of Māori waiata.

year: 2004-02