bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Abrasion on Stress-Strain Properties of Two Polyester/ Cotton Fabrics in Low-Level Laboratory Abrasion and Wear Trials
Authors: Raheel Mastura 
Published: March 2008

The effect of laboratory flex abrasion at low levels on two 65/35 and 50/50 polyester/cotton fabrics, as well as the effect of wearing of shirts made from the same fabrics, as mirrored in stress- strain properties, were investigated. Abrasive damage was monitored by measuring percent reten tion of breaking load, yield point, elastic limits, and elongation at rupture after varying levels of laboratory flex abrasion and wear plus laundering. Subjective evaluations by microscopic analysis of fabrics and yarns were also made, as well as evaluations by a panel of judges in regard to surface appearance, whiteness retention, and hand of the in-service shirts.A quantitative relationship could not be established between laboratory abrasion and in-service wear, because the stresses imposed during in-service wear were not high enough to produce the nature and extent of damage observed in laboratory abrasion. However, the two types of abrasion were similar enough that the properties being monitored changed in a similar fashion.It is concluded that the (Stoll) flex abrasion technique employed in this work has limited utility in predicting in-service wear, and that at low levels of abrasion 50/50 polyester/cotton performed as well as 65/35 polyester/cotton with the added quality of superior comfort associated with the cotton component.
Dyeing of Grafted Polyester Fiber
Authors: Faterpekar S.A. , Potnis S.P. 
Published: March 2008

Polyester fiber was modified by grafting with polyvinyl alcohol (PVA) by the irradiation process. Initially, polyester fiber was grafted with polyvinyl acetate and then hydrolyzed under suitable conditions to get polyester-graft-polyvinyl-alcohol. Crystallinity of the grafted fibers was determined by infrared, DSC, and x-ray analysis and was found to be identical for all the grafted fibers. Moisture regain increased with increase in PVA and had a value of 1.6% at 13% PVA content. The grafted fibers were dyed with disperse dyes: Dispersol Fast Yellow G and Duranol Red 2B at 100° and 130°C. Saturation dye uptake showed an initial increase with PVA, attained a maximum at about the 8% graft level, and then decreased at higher PVA contents. Half dyeing time decreased with PVA content, attained a minimum, and then showed an increase. Except for the numerical values, both dyes followed identical patterns at different temperatures.
Wear Life of Easy-Care Cotton Fabrics
Authors: Neelakantan P. , Mehta H.U. 
Published: March 2008

In this paper an attempt has been made to identify the physical properties of an easy-care 100% cotton fabric that can correlate with the end-use performance of garments made out of this fabric. For this purpose, two independent sets of data have been analyzed. From the first set of data the performance of the twelve plain-weave fabrics of different counts and constructions, but resin-finished and cured under similar conditions, have been obtained in terms of the number of wear-wash cycles that shirts made out of these fabrics could withstand before showing the first sign of damage. In the second set of data, from the literature, which included 400 experimen tal fabrics of different weaves and constructions, the performance has been obtained in terms of the number of laundry cycles that cuffed trouser legs could withstand before showing the first sign of damage. Preliminary studies on these data indicate that, in spite of the complexity of the phenomenon of wear, it is possible to draw conclusions on the wear performance of a fabric from a knowledge of its initial tear strength and elongation; further, there is no need to include the laboratory assessment of abrasion resistance. However, the values of the regression coefficients do not exhibit any trend with the weave or weight per unit area of the fabric. This suggests the need to identify other fundamental parameters that are related to the fabric wear life.
Applying Shrink Resist Polymers to Wool Fabrics at Room Temperature Using Pad-Store Methods
Authors: Lewis D.M. 
Published: March 2008

Shrink-resist finishing of wool fabrics using aqueous based polymer systems is usually carried out using an energy intensive pad → dry → heat cure technique. This paper describes fabric shrink-resist finishing using the Bunte salt terminated polyether, Lankrolan SHR3 (Diamond Shamrock), by a simple pad → store (room temperature) → wash-off procedure. Advantages of the method include low energy consumption, no fiber yellowing due to the absence of high temperature treatments under alkaline conditions, and ease of post dyeing. Evidence is presented for covalent reaction of the polymer with the fiber to form mixed disulphides, improving the stability of the shrink-resist finish to such agencies as post dyeing.
Vapor Transport of Formaldehyde to Cotton'
Authors: Reinhardt Robert M. 
Published: March 2008

A basic study of the transport of formaldehyde via the vapor phase to cotton was conducted. Fundamental physicochemical factors that influence vapor transport of formaldehyde to and from cotton fabrics were identified; these factors include time, temperature, and concentration parameters, which are interrelated, as well as source of the formaldehyde, nature of the fabric substrate, presence and amount of moisture, and confinement of the fabric. The effect on rate and amount of formaldehyde trans port was noted in experiments conducted with controlled adjustment of the variables. Observations on transport from formaldehyde-sorbed fabric to untreated fabric also were made. Results of this study provide information of value to those interested in finishing cotton with formaldehyde and in formaldehyde release phenomena of finished tex tiles.
Dyeing of Modified Polypropylene: Cationic Dyes on Chlorinated Polypropylene
Authors: Shah C.D. , Jain D.K. 
Published: March 2008

Polypropylene fiber was chlorinated by the action of sodium hypochlorite under specific conditions. On chlorination, the moisture content of the fiber increased, but there was no effect on the fiber's mechanical properties. On chlorination, marked affinity was created in the fiber for cationic dyes from alkaline medium. Eight different cationic dyes were used on the chlorinated product under different dye bath pH conditions. Dyeings tended to show that the mechanism of application of cationic dyes on chlorinated polypropylene was a reactive type, i.e., through the formation of a covalent bond between the fiber and the dye. Of the eight cationic dyes, seven possessed poor to moderate light fastness, only Methylene Blue (CI Basic Blue 9) gave very good light fastness. In all the eight dyeings, other fastness properties such as fastness to washing, bleach, sea-water, and soda-boil were good. All the eight dyeings were after-treated with iodine which increased light fastness. Of the eight dyes, four produced photodegrading action on the fiber and four afforded photoprotection. Methylene Blue gave very good photoprotective action to the chlorinated polypropylene fiber.
Design and Use of a Cyclic Tensile Abrader for Filaments and Yarns-A Study of Polyester Monofilament Wear
Authors: Miller B. , Friedman H.L. , Turner R. 
Published: March 2008

An apparatus has been developed that imposes an adjustable constant axial tensile load on filaments, yarns, or fabric strips during cyclic rubbing over pins in various configurations and under controlled temperatures and specific chemical environments. The action is intended to simulate the combinations of tensile, bending, and abrasive stresses experienced by fibrous materials during processing and end use. The number of cycles to rupture (or specimen lifetime) is automatically recorded, and there is provision for monitoring the elongation of the specimen under stress. The use of the cyclic tensile abrader is demonstrated by means of a study of the influence of tensile loading, temperature, and rubbing configuration on the wear of a polyester monofilament sample in air. The reproducibility of both lifetimes and elongations is good, and the results are in accord with expectations for the behavior of this material under the stresses and conditions imposed. It appears that the basic design of the cyclic tensile abrader makes it suitable as a research tool as well as an accelerated wear testing device.
Physicochemical Properties of Sized Yams
Authors: Slauson Sherilyn D. , Miller Bernard , Rebenfeld Ludwig 
Published: March 2008

Several methods were explored for characterizing sized yams and size films in order to establish relationships that might be useful in predicting weaving performance. A variety of natural and synthetic sizes were applied to cotton and to polyester/cotton spun yams in a laboratory sizing apparatus. Although yam tensile tests indicate that sizing generally increases yam strength and decreases yarn extensibility, these tests were inadequate for differentiating among sizing agents. Important differences among the various sizes and levels of size add-on could, however, be detected by measuring rupture lifetimes of the treated yarns using the TRI cyclic tensile abrader, which imposes simultaneous tensile, bending, and abrasive stresses. Two factors appear critical to size performance: the size must form a tough but flexible film to protect the yam from flexing and rubbing actions, and there must be good adhesion between size and yam. The flexibility requirement was established by correlating the tensile behavior of films prepared from the various size polymers with rupture lifetimes of the sized yams. The degree of adhesion was evaluated by measuring the wettability of the size films, using an adaptation of the Wilhelmy wetting force method, and matching the resulting contact angle hysteresis patterns.
Fluorescence and Phosphorescence of Wool Keratin Excited by UV-A Radiation
Authors: Smith G.J. , Melhuish W.H. 
Published: March 2008

Corrected fluorescence and phosphorescence spectra of wool keratin excited by UV-A radiation are presented. Some of the observed luminescence is believed to originate from N-formylkynurenine residues, which are photo-oxidation products of tryptophan residues. The positions of the spectral maxima of the fluorescence and phosphorescence arising from N-formylkynurenine residues indicate that there is hydrogen bonding between the ortho carbonyl group of N-formylkynurenine and the N-H group of a protein peptide linkage. The N-formylkynureninine residues also appear to be located principally in regions of low polarity.
Effect of Mercerization on the Relation Between Single Fiber Mechanical Properties and Fine Structure for Different Cotton Species
Authors: Aboul-Fadl S.M. , Zeronian S.H. , Kamal M.M. , Kim M.S. , Ellison M.S. 
Published: March 2008

Five G. barbadense species obtained from Egypt (Dendara, and Gizas 75, 76, 77, and 80), one American G. barbadense cotton (Pima S-5), and one American G. hirsutum cotton (Deltapine Smooth Leaf) were studied. Mercerization appeared to decrease the crystallinity of the G. hirsutum cotton more than that of the G. barbadense types. The mercerization treatment also appeared to have swollen the G. hirsutum fibers by a greater amount. The large increase in breaking load of the Deltapine Smooth Leaf cotton, which occurred on mercerization, may be due to the lower crystallinity and smaller crystallite lengths induced in these fibers by this treatment. The breaking load of the G. barbadense fibers either increased by smaller amounts than that obtained with the G. hirsutum sample or it fell. Mercerization appeared to reduce the brittleness of the Egyptian G. barbadense varieties; however, the changes were small and with Dendara, insignificant. For Pima S-5, brittleness did not change, and with Deltapine Smooth Leaf, the apparent increase in brittleness was insignificant. Mercerization appeared to improve the flex lives of the Giza 76, Giza 80, Pima S-5, and Deltapine Smooth Leaf samples, but the evidence for an increase was not as strong in the case of Giza 75, Giza 77, and Dendara. Mercerized Gizas 76 and 77 appeared to have the shortest flex lives of all the mercerized G. barbadense samples tested.
Thermomechanical Analysis of the Stress History in Heat Set Nylon 6 Carpet Yarns
Authors: Dennis L.A. , Buchanan D.R. 
Published: March 2008

Tension effects during a commercial heat setting process were investigated through the analysis of the thermomechanical behavior of heat set nylon 6 carpet yarns. The stress history of these yarns was modified by altering the yarn tension level at various positions along the Superba continuous heat setting process. Changes in fiber structure and morphology were characterized by mechanical testing, shrinkage measurements, differential scanning calorimetry, and thermal stress analysis. A model based on the hypothesis that there are two domains of molecular order that respond differently to the effects of stress, such that structural and morphological changes proceed via two distinct mechanisms, was fit to the experimental shrinkage force-temperature curves and described the experimental curves very well. Changes in the calculated curve parameters were highly correlated with the observed changes in shrinkage and initial moduli. Each of these changes was a function of the tension state of the nylon 6 yarns during the heat setting process. Analysis of the shrinkage force curves and their characteristic parameters showed that this technique is capable of identifying subtle variations in fiber microstructure and therefore has significant applications to the identification of stress history differences in heat set fibers and yams.
Modeling Woven Fabric Tensile Strength Using Statistical Bundle Theory
Authors: Shahpurwala A.A. , Schwartz P. 
Published: March 2008

Previous statistical models, developed to predict the strength of loose fiber bundles and composite materials, have been applied to the problem of predicting the tensile strength of woven fabrics when the underlying strength distributions of the warp and weft threads are known. The woven fabric was first assumed to act as a single loose bundle of threads with no thread interactions (equal load sharing), and Daniels' model was applied. In the second stage, a more complex chain-of-bundles model, which provides a method to take interactions into account, was then used. With this model, the effect of interactions due to interyarn friction and thread crimp can be seen in the number of sub-bundles forming the chain. The length of each of these sub-bundles, called the "overload length," is a measure of the influence of the crossing threads. Finally, a third refinement that accounts for interactions through localized, non-equal load sharing among yams was used. Experiments were performed using four different fabrics—three cotton fabrics of plain, twill, and satin construction, and one 100% polyester fabric of plain construc tion—to determine the applicability of the models. Warp and weft yams were extracted from the fabrics and tested in tension. The strength data for these yams were fitted to a two-parameter Weibull distribution using the method of maximum likelihood. The simple loose bundle model consistently underestimated the fabric strength, although the predicted values were generally better for the fabrics with longer float lengths, indicating that interyarn friction from the interlacings plays a positive role in fabric tensile strength. With the chain-of-bundles model, the ratio of the thread crimps is a predictor of the overall frictional effect. Localized load sharing results in a conservative approach, with the actual fabric properties falling between this and the simpler chain- of-bundles model incorporating equal load sharing.
A construct definition study of a standardized ESL vocabulary test
Authors: Perkins Kyle , Linnville Steven E. 
Published: March 2008

This paper reports a construct definition study of a standardized English as a second language (ESL) vocabulary test. The test, which contained 20 stimulus word items and 17 context word items, was administered to two different samples of ESL students at different proficiency levels and to a sample of native speakers of English. The item responses for the 40 items were used as the dependent variable in a stepwise multiple regression, construct specification equation and 12 variables (measures of the stimulus words' and keyed responses' fluency, distribution, abstractness, length, affective impact, and prototypicality) were used as predictors. Only six of the predictors accounted for a significant amount of variance in the dependent variable, and the number and arrangement of significant predictors varied across proficiency strata, indicating the utility of incorporating the examinees' stages of learning into construct validation studies. Construct definition studies such as the current one permit the statement of explicit predictions and a means to falsify construct theory, which is a perceived need in educational and psychological measurement. The paper concludes with an agenda for future research based on the results of the present study.
The language used to perform cognitive operations during full- immersion maths tasks
Authors: Cohen Andrew D. 
Published: March 2008

Thirty-two students were selected from the third to sixth grade at a Spanish full-immersion school in St Paul. A team of five investigators collected data from the pupils over a five-month period: 1) verbal report; 2) questionnaire data about the pupils' abilities, attitudes and preferences with regard to thinking in Spanish and using Spanish as a vehicle for communication with peers and adults; 3) insights from classroom observation regarding language use patterns in the process of doing the particular task; and 4) background information on the selected learners, including achievement test scores available from the school office, the learners' school grades, sociolinguistic information on their exposure to Spanish language out of class, and so forth. The findings revealed that, for the immersion students under study, English seemed at times to play a more prominent role in their internal language environment than Spanish. In responding to both numerical and verbal problems in maths, students reported favouring English in their cognitive processing and were also observed to be doing so. They read the problem in Spanish but would shift to English immediately or as soon as they had some conceptual difficulty. These findings may provide some contribu tion to the gaps that have been noted in the spoken and written output of immersion pupils.
TOEFL preparation courses: a study of washback
Authors: Alderson J. Charles , Hamp-Lyons Liz 
Published: March 2008

'Washback' (sometimes also known as 'backwash') is the influence that writers on language testing, syllabus design and language teaching believe a test will have on the teaching that precedes it. Much has been written about the influence of testing on teaching. To date, however, little empirical evidence is available to support the assertions of either positive or negative washback. The English proficiency test TOEFL (Test of English as a Foreign Language: ETS) is among the best-known examinations in the field of ELT. The study reported in this article set out to investigate common claims that the TOEFL exerts an undesirable influence on language teaching. Our data consist of interviews with teachers and students, and observations made of two sorts of classes: 'normal' language proficiency classes, and parallel classes intended for students preparing to take the TOEFL. We observed both TOEFL preparation classes and non-TOEFL preparation classes by the same teachers in order to be able to separate washback from the TOEFL from any possible effect of individual teacher style. This study leads us to suggest that simple forms of washback hypotheses are too naive: influences on what happens in class are much more complex than unexamined beliefs about washback allow. The results of the study suggest the need for more complex hypotheses about washback.
The effect of interlocutor and assessment mode variables in overseas assessments of speaking skills in occupational I settings
Authors: McNamara T.F. , Lumley Tom 
Published: March 2008

The increasing demand for performance assessment of speaking skills in second languages has led to logistic complications, for example, the delivery of tests in overseas locations. One solution to the problem has been to train native speaker interlocutors to carry out a series of oral interactions with the candidate, with assessment from audiorecordings of the test session postponed and conducted cen trally by a small team of trained raters. This technique is currently used in two large-scale occupationally related ESP tests administered internationally on behalf of the Australian government. But these procedures raise questions about the effect of such facets of the assessment situation as interlocutor variables and the quality of the audiotape recording. Recent developments in multifaceted Rasch measure ment have significantly broadened the possibilities for investigation of these issues. The research presented in this article investigates potential problems associated with the above approach to the offshore testing of speaking skills. Data from audiotape-based assessments of 70 offshore candidates from two administrations of the Occupational English Test, an advanced-level ESP test for health pro fessionals, are considered. In addition to multiple ratings of candidate perform ance, each recording is rated for perceptions of the competence of the interlocutor, the rapport established between the candidate and the interlocutor, and the audi bility of the interaction. These aspects of the assessment situation are treated as facets in a series of multifaceted Rasch analyses of the data. The results of the analysis reveal the effects of interlocutor variability and audio tape quality on ratings. The article concludes with an evaluation of the overall feasibility of the procedure, and implications for test administration are considered. The study is also a further demonstration of the application of multifaceted Rasch measurement in performance assessment settings.