Search results

The limiting irregularity of yarn is the minimum count variation expected from ideal yarn with a random fibre ends distribution. It can be calculated with the Martindale limiting irregularity model which takes into account the changes in the number of fibres in yarn crosssection and the variations in fibre cross-sectional areas. However, the variations in fibre cross-sectional areas are calculated from between-fibre diameter variations only, without considering the within-fibre diameter variations. Wool fibres exhibit diameter variations both between fibres and within fibres. Ignoring the within-fibre diameter variations may lead to an underestimation of yarn limiting irregularity. This paper reports an improved model for calculating the limiting irregularity of wool yarn, incorporating both between-fibre and within-fibre diameter variations of the constituent wool fibres. Experimental verification shows that this model can predict yarn limiting irregularity more accurately than the existing one. Based on this improved yarn limiting irregularity model, an improved effective fineness model which also incorporates both within-fibre and between-fibre diameter variations has been established.

Based on clarifying the structural difference between jade fibre and general polyester fibre, this paper aims to study the dyeing properties and dyeing adsorption mechanism of jade fibre with disperse dye and cationic dye.

The chemical structure and microstructure of jade fibre were briefly explained comparing with ordinary polyester fibre. The dyeing rate curve and dyeing adsorption isotherm of disperse dyes and cationic dyes on jade fibre were, respectively, studied. The dyeing uptake, dyeing absorption mechanism, and the main dyeing process parameters were proposed.

Jade fibre can be dyed with cationic dye and disperse dye. The suitable exhaust dyeing process is 110°C and 40 minutes for disperse dye, 100°C and 60 minutes for cationic dye. The dyeing uptake on jade fibre with both disperse dyes or cationic dyes is much higher than that on general polyester fibre and acrylic fibre, and the dyeing adsorption mechanism belongs to the combination of Langmuir and Nernst adsorption for disperse dyes and Langmuir adsorption for cationic dyes. Comparing with ordinary polyester fibre, jade fibre has the advantage of low temperature dyeing and reduced effluent, as is significant to energy-saving and emission reduction.

Jade fibre is a new type of modified polyester fibre with the function of health protection and energy conservation. There are little technical data in the literature at present about the dyeing property of jade fibre.

This study aims to scrutinise the impact of fibre length and its composition on the tribological attributes of oil palm fibre (OPF) polymeric composite as an alternative brake friction material.

Fabrication of the sample was conducted by using a hot-compression method. The tribological test was carried out by deploying a ball-on-disk tribometer. Analysis of the data was then done by using the Taguchi approach as well as analysis of variance.

The results indicated that all design variables (fibre composition, length and treatment) are not statistically significant, as all p-values are greater than 0.05. Remarkably, irrespective of the fibre treatment, the wear rate and coefficient of friction (COF) distribution suggested that a smaller fibre length with a high fibre composition might enhance the composite’s tribological performance with COF of 0.4 and wear rate below than 1 × 10^–9 mm³/Nm. The predominant wear mechanisms were identified as micro-cracks, fine grooves and fibre debonding.

In this study, all-inclusive scrutiny needs to be carried out for further exploration.

The main contribution and novelty of this study are opening a new perspective on the formulation of new substances from bio-based material (i.e. OPF) that possess superior tribological characteristics for friction-based applications.

The use of fibre optic sensors is a relatively new development but the future applications are enormous

To reveal the mechanism of fibre damage and breakage in the fibre opening processes, the fibre tension during the interaction between a fibre and a pinned beater has been investigated. Details of the interacting force variations and incident of fibre breakage have been closely examined. Many factors which influence the fibre/pin interacting force have been elucidated. The results highlight the causes of fibre damage and breakage by fibre/pin interactions.

There is considerable epidemiological and direct experimental evidence concerning the nutritional benefits of dietary fibre. Over the last few years, and particularly as a result of the publication of The F‐Plan Diet, public awareness and interest in this topic has increased enormously in the UK and there has been a growing demand both for information about the dietary fibre content of foods and for food products containing higher levels of dietary fibre. It is becoming increasingly important, therefore, to understand exactly what is meant by the term ‘dietary fibre’. In this article Helen F. Kearns, BSc and Gillian D.A. Lowy, MA, review the methods that are used for the determination of fibre in foodstuffs, outline some of the physiological effects of dietary fibre, and discuss how values quoted for the dietary fibre contents of foods may be interpreted in the light of their physiological role.

Presents a mathematical treatment of the large‐scale bending behaviour of multi‐ply yarn. Based on the assumptions that: each individual fibre in the yarn has the form of a doubly‐wound helix; each fibre is an inextensible slender rod; and interaction between fibres is ignored. The yarn‐bending rigidity is calculated as an average rigidity of an assembly of coaxial helices. There is good agreement between the predicted and measured values of yarn bending rigidity for a wool worsted knitting yarn. Also predicts the position, curvature and twist components as well as the strain energy of the deformed fibre.

The purpose of this paper is to improve the dyeability of flax fibre by modification via urea treatment and to explore the mechanism of such improvement.

The modification to the flax fibre was carried out with different concentrations of urea solution, then the optimum condition for the dyeability improvement was investigated by the measurement of the dyeing colour depth. The chemical properties of the raw and the treated flax fibres were characterised using a variety of techniques including Fourier transform‐infrared spectroscopy analysis and X‐ray photoelectron spectroscopy analysis.

It was found that the dyeability of flax fibre had been significantly improved via urea treatment. The mechanism of the improvement of the dyeability of the flax fibre was found to be due to the amino groups (NH₂) introduced to the flax fibres during urea treatment, which increased the activity of the reaction between the dye and the fibre compared to hydroxyl groups of raw flax fibre.

The treatment method developed provided a practical and effective solution to poor dyeability of flax fibre.

The method could be adapted for use in industrial scale flax dyeing with satisfactory levels of exhaustion and fixation.

Optical fibre sensors are finding wide applications in biotechnology and medicine, as a European specialist explains.

Numerous articles have been written about the many applications for fibre optic sensors and their future potential. However, very few products are yet in volume production.