The photostability of wool doped with photocatalytic titanium dioxide nanoparticles

Photoyellowing of wool is a serious problem for the wool industry. This study assessed the role of photocatalytic nanocrystalline titanium dioxide (P-25) as a potential antagonist or catalyst in the photoyellowing of wool. Untreated, bleached and bleached and fluorescent-whitened wool slivers were processed into fine wool powders for the purpose of even and intimate mixing with the TiO2 nanoparticles in the solid state. Pure wool and wool/TiO2 mixtures were then compressed into solid discs for a photoyellowing study under simulated sunlight and under UVB and UVC radiations. Yellowness and photo-induced chemiluminescence (PICL) measurements showed that nanocrystalline TiO2 could effectively reduce the rate of photoyellowing by inhibiting free radical generation in doped wool, and that a higher concentration of TiO2 contributed to a lower rate of photooxidation and reduced photoyellowing. Hence nanocrystalline TiO2 acts primarily as a UV absorber on wool in dry conditions and not as a photocatalyst.

Coarser wool is not a necessary consequence of sheep aging: allometric relationship between fibre diameter and fleece-free liveweight of Saxon Merino sheep

The mean fibre diameter (MFD) of wool is the primary determinant of price, processing performance and textile quality. This study determines the primary influences on MFD as Saxon Merino sheep age, by allometrically relating MFD to fleece-free liveweight (FFLwt). In total, 79 sheep were grazed in combinations of three stocking rates and two grazing systems (GS: sheep only; mixed with Angora goats) and studied over 3 years. Measurements were made over 14 consecutive periods (Segments), including segments of FFLwt gain or FFLwt loss. Using shearing and liveweight records and dye-bands on wool, the FFLwt and average daily gain (ADG) of each sheep were determined for each segment. The mean and range in key measurements were as follows: FFLwt, 40.1 (23.1 to 64.1) kg; MFD, 18.8 (12.7 to 25.8) μm. A random coefficient restricted maximum likelihood (REML) regression mixed model was developed to relate the logarithm of MFD to the logarithm of FFLwt and other effects. The model can be written in the form of ${\rm MFD}\,{\equals}\,\rkappa \left( {{\rm GS,}\,{\rm A}{\rm ,}\,{\rm Segment}{\rm .Plot,}\,{\rm Segment,}\,{\rm ADG}} \right){\times}{\rm FFLwt}^{{\left( {\ralpha \left( {{\rm GS}} \right){\plus}\rbeta \left(\rm A \right){\plus}\rgamma \left( {{\rm Segment}{\rm .Plot}} \right)} \right)}} $ , where $\ralpha \left( {{\rm GS}} \right)\,{\equals}\,\;\left\{ {\matrix{\!\! {0.32\left( {{\rm SE}\,{\equals}\,{\rm 0}{\rm .038}} \right)\,{\rm when}\,{\rm sheep}\,{\rm are}\,{\rm grazed}\,{\rm alone}} \hfill \cr \!\!\!\!{0.49\left( {{\rm SE}\,{\equals}\,{\rm 0}{\rm .049}} \right)\,{\rm when}\,{\rm sheep}\,{\rm are}\,{\rm mixed}\,{\rm with}\,{\rm goats}} \hfill \cr } } \right.$ β(A) is a random animal effect, γ(Segment.Plot) a random effect associated with Segment.plot combinations, and κ a constant that depends on GS, random animal effects, random Segment.plot combination effects, Segment and ADG. Thus, MFD was allometrically related to the cube root of FFLwt over seasons and years for sheep, but to the square root of FFLwt for sheep grazed with goats. The result for sheep grazed alone accords with a primary response being that the allocation of nutrients towards the cross-sectional growth of wool follicles is proportional to the changes in the skin surface area arising from changes in the size of the sheep. The proportionality constant varied systematically with ADG, and in sheep only grazing, was about 5 when sheep lost 100 g/day and about 6 when sheep gained 100 g/day. The proportionality constant did not systematically change with chronological age. The variation in the allometric coefficient between individual sheep indicates that some sheep were more sensitive to changes in FFLwt than other sheep. Key practical implications include the following: (a) the reporting of systematic increases in MFD with age is likely to be a consequence of allowing sheep to increase in size during shearing intervals as they age; (b) comparisons of MFD between sheep are more likely to have a biological basis when standardised to a common FFLwt and not just to a common age;

Fabric and greasy wool handle, their importance to the Australian wool industry: a review

Handle-related properties of woollen fabrics have been demonstrated to be major factors affecting consumer buying attitudes. Handle is the combination of both textural and compressional attributes. Compressional handle has demonstrated processing advantages in woven and knitted fabrics. The handle of processing lots can be manipulated using a variety of technologies but direct manipulation of textural greasy wool handle pre-processing is still crude. On-farm, there is documented evidence that including handle assessment in a selection index provides additional improvements in genetic gain. However, the assessment of greasy wool handle is based on a tactile evaluation of the wool staple by sheep and wool classers, and its application is affected by a lack of framework that instructs assessors on a standard method of assessment. Once a reliable and repeatable protocol is developed, further understanding of the effect greasy wool handle has on final garment quality will be possible.

Functionality of nano titanium dioxide on textiles with future aspects: focus on wool

The consumption of titanium dioxide in today's world is on the increase. As the most popular nano substance, TiO 2 is used in various industries notably in the textile industry. More and more recently, through a synergistic combination of photocatalytic features of nanoparticles, fabrics with novel properties are produced. Self-cleaning and stability against UV rays as well as chemical media, to name but a few, are among new prominent properties, obtained on textiles. A common subject reported in most studies has been the diverse approaches to immobilize the nanoparticles on the surface of fabrics. Wool is among common textile materials that have undergone numerous processes to be modified. This review intends to bring to light different aspects of application of nano titanium dioxide in the textile industry especially on wool, and also presents a concise overview on the rigorous pieces of research conducted in this realm.

Electrical conductivity of single walled and multiwalled carbon nanotube containing wool fibers

The main purpose of this study was producing conductive wool fabric applying carbon nanotubes. Raw and oxidized wool samples were treated with carbon nanotubes in the impregnating bath in the presence of citric acid as a crosslinking agent and sodium hypophosphite as a catalyst while sonicating them in the ultrasonic bath. Electrical resistance, washing durability, and color variation of treated samples were assessed. Through SEM images, the surface morphology of treated samples was studied confirming the surface coating through carbon nanotubes. According to the results, the electrical resistance of treated wool with carbon nanotubes reduced substantially. However, the single-walled carbon nanotubes are more useful to increase the conductivity. In addition, the wool color changed into gray after the treatment.

Novel feature of nano-titanium dioxide on textiles: antifelting and antibacterial wool

In this study, the antifelting and antibacterial features of wool samples treated with nanoparticles of titanium dioxide (TiO2) were evaluated. To examine the antifelting properties of the treated samples, the fabric shrinkage after washing was determined. The antimicrobial activity was assessed through the calculation of bacterial reduction against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. TiO 2 was stabilized on the wool fabric surface by means of carboxylic acids, including citric acid (CA) and butane tetracarboxylic acid (BTCA). Both oxidized samples with potassium permanganate and nonoxidized wool fabrics were used in this study. The relations between both the TiO2 and carboxylic acid concentrations in the impregnated bath and the antifelting and antibacterial properties are discussed. With increasing concentration in the impregnated bath, the amount of TiO2 nanoparticles on the surface of the wool increased; subsequently, lower shrinkage and higher antibacterial properties were obtained. The existence of TiO2 nanoparticles on the surface of the treated samples was proven with scanning electron microscopy images and energy-dispersive spectrometry.

Photo induced silver on nano titanium dioxide as an enhanced antimicrobial agent for wool

In this study an effective nanocomposite antimicrobial agent for wool fabric was introduced. The silver loaded nano TiO(2) as a nanocomposite was prepared through UV irradiation in an ultrasonic bath. The nanocomposite was stabilized on the wool fabric surface by using citric acid as a friendly cross-linking agent. The treated wool fabrics indicated an antimicrobial activity against both Staphylococcus aureus and Escherichia coli bacteria. Increasing the concentration of Ag/TiO(2) nanocomposite led to an improvement in antibacterial activities of the treated fabrics. Also increasing the amount of citric acid improved the adsorption of Ag/TiO(2) on the wool fabric surface leading to enhance antibacterial activity. The EDS spectrum, SEM images, and XRD patterns was studied to confirm the presence of existence of nanocomposite on the fabric surface. The role of both cross-linking agent and nanocomposite concentrations on the results was investigated using response surface methodology (RSM).

Self-cleaning and color reduction in wool fabric by nano titanium dioxide

Wool is a textile material that is valued for its strength, warmth, water resistance, and texture. But this natural fiber of the protein keratin lacks the stain resistance of synthetic fabrics and is also generally susceptible to harsh processing conditions. In this study, raw and oxidized wool fabrics were treated with nano titanium dioxide (TiO2) powder in an ultrasonic bath. These particles were linked to the wool surface by butane tetra carboxylic acid and also sodium hypophosphite was used as a catalyst. The photo-catalytic activity of TiO2 nanoparticles deposited on the wool fabrics was followed by the degradation of Acid Blue 113 as a stain and also determined by the degradation rate of food stains such as coffee, tea, and fruit juice under the ultraviolet rays. The results showed that increasing the amount of nano TiO2 leads to improved degradation of stains on the treated fabric.

Nano titanium dioxide on wool keratin as UV absorber stabilized by butane tetra carboxylic acid (BTCA): a statistical prospect

Photo yellowing of wool is one of the most important problems which have negative impacts on various aspects of wool prompting scientists to find a solution over the past decades. In this research the protective features of nano-titanium dioxide particles against UV on wool fabric were discussed and the color variations of wool samples after UV irradiation were measured and reported. It was shown that nano TiO2 is a suitable UV absorber and its effect depends on the concentration. Also, it was assumed that butane tetracarboxylic acid plays a prominent role as a cross-linking agent to stabilize the nano-titanium dioxide as well as a polyanion to maintain negative charges on the wool surface for higher nano particles absorption. Also the variables conditions were optimized using response surface methodology (RSM).

Reducing photoyellowing of wool using nano TiO2

Wool is the most important animal fiber used in textile industries, but its photostability is very low. Scientists have searched for new ways to increase the photostability of wool. As TiO2 nano particles have features suitable for new applications, the UV-blocking power of nano TiO2 may be used for protecting fabrics against UV rays. Treatment of wool with TiO 2 can be effective for controlling photodegradation. This study focused on protecting wool fabric against UV rays using nano TiO2. To this end, oxidized and raw wool were treated with citric acid as the cross-linking agent and different concentrations of nano TiO2. The whiteness and yellowness of wool fabric samples were reported. XRD patterns proved the existence of TiO2 nano-particles on the wool surface. Finally, the results revealed that nano TiO2 is a suitable UV absorber on wool fabric and its effect depends on concentration.

Thermoregulatory response in hair sheep and shorn wool sheep

This study’s main goal was to evaluate the thermoregulatory responses velocity through the variation of rectal temperature (RT), related to the thermolytic pathways, respiratory rate (RR) and sweating rate (SR) among different sheep breeds. Ninety female sheep, eighteen of each breed: Santa Ines and Morada Nova (Brazilian hair breeds), Texel, Suffolk and Ile de France (wool breeds) were challenged during three non-consecutive summer days (22◦42′S, 47◦18′W, and 570m of altitude, maximum air temperature of 33.5◦C, average relative humidity of 52±6.9%). The physiological variables were registered at 0800h (T1), 1300 h (T2: after 2 h of shade rest), 1400 h (T3) (after one hour of sun exposure) and in the shade at 1415 h (T4), 1430 h (T5), 1445 h (T6) and 1500 h (T7) and a thermotolerance index (TCI) was calculated as (10-(T7 to T4)-T1). The statistical analysis was performed by a mathematical model including the fixed effects of breeds and time frames, and the interaction between these effects, besides random effects such as animal and day. The Santa Ines breed presented the lowest RT after sun exposure (39.3 ± 0.12 ◦ C; P < 0.05) and it was the only one to recover morning RT 60 min after heat stress (38.7 and 38.9 for 1300 h and 1500 h; P > 0.05). Hair breeds presented RR lower (P < 0.05) than wool breeds. Although thick wool or hair thickness differs among and within hair and wool breeds (P < 0.05), SR did not differ among breeds and time (227.7 ± 16.44 g m−2 h−1 ; P > 0.05). The thermotolerance index did not differ among breeds, but it showed similar response (P > 0.05) 45 min or 1 h of shade after sun exposure. One week post shearing is not enough to wool breeds present to show thermotolerance similar to hair breeds.

Professional education in built environment and design

Early and rich conversations with a range of stakeholders – academics, professionals and graduates in their early years of practice – quickly clarified that the singular challenge for most parties centres on the ways in which courses prepare graduates for the pace, diversity and flux of contemporary professional practice.---------In pursuing understanding of this central challenge this study has focused on new graduates in BED disciplines by canvassing their views and those of two other major stakeholder groups (academic staff and professional practitioners in the disciplines studied). The first crucial years of a young graduate’s life in the workforce are shaped by a number of factors including the quality of the transition-to-work experience. The quality of this life-shaping transition is dependent on a range of factors including the ways in which graduates are educated in universities, their personal developmental characteristics and those of the professional people around them and the preparedness of workplaces and other professional groups to guide new recruits through the transition experience. This study makes recommendations about how the variations in transition experience, resulting from the vagaries of all these factors across a range of worksites, may be better understood, perhaps normalised, and, at least, supported. . Early and rich conversations with a range of stakeholders – academics, professionals and graduates in their early years of practice – quickly clarified that the singular challenge for most parties centres on the ways in which courses prepare graduates for the pace, diversity and flux of contemporary professional practice. The study proceeded through literature review, focus group interviews, national online survey and workshops. Through all these methods a number of challenges and factors essential to the transition experience, and the quality of education which precedes it, were identified. Firstly the study found further evidence of the importance of higher-order graduate capabilities, namely, the development of judgment, critical enquiry and strategic thinking. Alongside these capabilities the importance of the development of emotional intelligence, particularly interpersonal and social skills, was stressed by all stakeholders. At the time of writing the global economic crisis was providing challenges to the sector and its young graduates. This phenomenon proved the value of the development of resilience and persistence in graduates, the education system was called upon by all stakeholders as a place where the future-proofing of neophytes would ensure that the unknown challenges of the future could also be confronted. The study found that the challenges of transition to work are best supported by authentic undergraduate experiences both on and off campus, inside and outside classrooms, and that commencing professional life is made easier for new graduates when university courses and workplace settings develop, sustain and support high standards and high expectations of students. All these findings indicate the importance of stakeholder expectations, roles and responsibilities in respect of the transition-to-work experience. Whilst full agreement about how these things should occur is not necessary, a process (amongst stakeholders) which seeks value alignment around transition through discussion, debate and agenda-setting would probably assist to address what is seen as a major challenge in built environment and design education.

Animal Control - What constitutes a reliable cue to stop animal movement ?

Controlling free-ranging livestock requires low-stress cues to alter animal behaviour. Recently modulated sound and electric shock were demonstrated to be effective in controlling free-ranging cattle. In this study the behaviour of 60, 300 kg Belmont Red heifers were observed for behavioural changes when presented cues designed to impede their movement through an alley. The heifers were given an overnight drylot shrink off feed but not drinking water prior to being tested. Individual cattle were allowed to move down a 6.5 m wide alley towards a pen of peers and feed located 71 m from their point of release. Each animal was allowed to move through the alley unimpeded five times to establish a basal behavioural pattern. Animals were then randomly assigned to treatments consisting of sound plus shock, vibration plus shock, a visual cue plus shock, shock by itself and a control. The time each animal required to reach the pen of peers and feed was recorded. If the animal was prevented from reaching the pen of peers and feed by not penetrating through the cue barrier at set points along the alley for at least 60 sec the test was stopped and the animal was returned to peers located behind the release pen. Cues and shock were manually applied from a laptop while animals were observed from a 3.5 m tower located outside the alley. Electric shock, sound, vibration and Global Position System (GPS) hardware were housed in a neck collar. Results and implications will be discussed.

Exposed

Curation of a fashion parade (Exposed) of QUT student swimwear designs held in conjunction with the ‘Woollen Mermaids’ (history of swimwear) exhibition at QLD Museum. The research explored the exhibition of ‘cutting edge’ swimwear produced with non-traditional fabrics (wool) and experimented with display /presentation styles for fashion parades in museum settings. The paid ticketed event was attended by over 800 people.

Learning Landscapes 2.0: Adaptable educational environments

This project has blended two streams of enquiry: temporary and transportable construction technology, and flexible blended-learning environments. It seeks to develop prototypes for a series of environments suited for the activities of learning (future-proofed schools), as practiced in the twenty first century. The research utilises techniques of: historic survey, case study, first-hand observation, and architectural design (as research). The design comprises three major components: The determinate landscape: in-situ concrete ‘plate’ that is permanent. The indeterminate landscape: a kit of pre-fabricated 2-D panels assembled in a unique manner at each site to suit the client and context; manufactured to the principles of design-for-disassembly. The stations: pre-fabricated packages of highly-serviced space connected through the determinate landscape. This project was submitted to the ‘Future Proofing Schools’ competition (professional category) in October 2011. The competition was part of a research project supported under the Australian Research Council’s Linkage Grant funding scheme (project LP0991146).