It has been reported for several decades that microbes, which naturally contaminate cotton fibres during crop growth and subsequent storage can have an adverse effect on the structural quality of ...cotton lint. Although several studies have analysed the relationship between numbers of Gram-negative bacteria or bacterial endotoxin and particular physical properties, these studies have been limited to cotton from the United States, and the possible effects of fungal contamination have not been examined in detail. This study quantified the Gram-negative bacteria and fungal cells, as well as measuring concentrations of bacterial endotoxin and fungal glucan, on cotton lint samples from international sources. Spearman's rank correlation coefficients calculated between these results and quality data analysed by an automated testing instrument revealed several significant correlations. Findings included inverse correlations between the biological contamination parameters and fibre elongation, micronaire and reflectance. The possible causes and implications of these findings were also discussed.
Recently, attention was again drawn to the use of microspectrophotometry to distinguish between fibres dyed with indigo and seven derivative dyes. Under normal circumstances, fibres dyed with indigo ...(Vat Blue 1 or CI Number 73000) are not included in fibre-transfer examinations as, being ubiquitous, they do not usually have any evidential value. Indigo substitutes are used for fashion dyeing. If their use is widespread, the assumption that all denim material is dyed with Vat Blue 1 may need revising. A positive finding might make it necessary to reconsider the use of certain denim fabrics as capable of providing target fibres. Fibres from 160 samples of denim articles in current use were examined by microspectrophotometry to determine whether either indigo derivative dyes, or other dyes, had been used instead of the traditional indigo.
Seed coat fragments are a major source of cotton yarn imperfections. This article discusses the factors influencing the disruption caused by seed coat fragments in ring-spun yarn structure with a ...focus on three characteristics: the fragment's size, the amount of fibres attached to it and its position relative to the yarn core. The three characteristics were investigated through two experiments involving various types of yarn defects and a range of ring-spun yarn counts. Results presented in this article indicate that the three factors considered have a significant influence on the intensity of the disruption the seed coat fragment causes in the yarn structure, and are determinant of the type of defect that this disruption engenders (short/long defect).
Abstract
The use of non-wovens as absorbent products is increasing, as is the consumption of cotton fibres as raw materials for these products. This paper presents some results concerning the ...obtaining of absorbent non-woven products made from cotton fibres. A fibrous web was formed by the superposition of cotton bands as a short layer. Special needle types supplied by SINGER Spezialnadelfabrik GmbH & Co. KG were used during the needle-punching process. Equations of variation of liquid absorption speed and surface weight have been analysed in order to optimise the needle-punching process of the cotton fibrous webs.
It has been reported for several decades that microbes, which naturally contaminate cotton fibres during crop growth and subsequent storage can have an adverse effect on the structural quality of ...cotton lint. Although several studies have analysed the relationship between numbers of Gram-negative bacteria or bacterial endotoxin and particular physical properties, these studies have been limited to cotton from the United States, and the possible effects of fungal contamination have not been examined in detail. This study quantified the Gram-negative bacteria and fungal cells, as well as measuring concentrations of bacterial endotoxin and fungal glucan, on cotton lint samples from international sources. Spearman's rank correlation coefficients calculated between these results and quality data analysed by an automated testing instrument revealed several significant correlations. Findings included inverse correlations between the biological contamination parameters and fibre elongation, micronaire and reflectance. The possible causes and implications of these findings were also discussed.PUBLICATION ABSTRACT
Because cellulases are finding more applications in the textile and detergent industries, their effect on cotton fibres must be evaluated. For this purpose, the action of a recombinant cellulase, ...endoglucanase V from the fungus Humicola insolens, has been followed by scanning electron microscopy (SEM) in classical longitudinal views as well as in cross-sections of cotton fibres. The experiments were conducted at large enzyme dilution typical of conditions where cellulases are used for biopolishing, i.e. for the removal of defects created by mechanical abrasion. Endoglucanase V appears to restrict its action to the hydrolysis of the loose fibrils created at the surface of the fibres and no indication of extensive enzyme penetration and damage to the interior of the fibres could be detected by SEM. The adsorption sites for endoglucanase V on cotton fibres were examined by transmission electron microscopy (TEM) on ultrathin cross-sections after immuno-gold labeling of the enzyme. This approach showed that the enzymes did not penetrate the fibres but remained at their surface. The use of an immuno-gold labeled cellulase provides a new way to probe the surface features of cotton fibres
Significant differences in nucleolar size at early stages of cotton fibre development have been observed between bolls of different fruiting branches. Cutting off the apex or removal of the leaf ...subtending the cotton boll 6 d before flowering or emasculation followed by an addition of GA3 resulted in a significant decrease of the nucleolar size. Excising half of the roots had no influence on the nucleolar activity. The differences in nucleolar size between bolls of the first and fifth fruiting branches remained significant except in the case where the leaf subtending the boll was removed.
