Tensile characteristics of Dref‐III friction core‐spun yarns

The tensile characteristics of Dref‐III friction spun yarns with jute as core and cotton as sheath components have been studied. Three yarns with different core–sheath proportions such as 55/45, 65/35 and 75/25 jute/cotton friction spun yarns were produced by using the Dref‐III friction spinning system. The influence of core and sheath components on the tensile properties at three different traverse rates at 150 mm/min, 750 mm/min and 1500 mm/min, respectively, have been reported. The work of rupture and specific work of rupture at break of these yarns were also analysed. From the test results, the maximum work of rupture was found in 55/45 core–sheath (jute/cotton) friction spun yarn when compared to 65/35 and 75/25 core–sheath (jute/cotton) friction spun yarns. It is due to the higher core–sheath interaction factor (CSI_T = 26.14) and better yarn‐packing density because of higher proportion of cotton fibres in the sheath component. The breaking tenacity and contribution factor of core and sheath component (CSI_T) of jute/cotton friction spun yarns were also analysed using multivariable ANOVA analysis.     

Study of fiber packing density of lyocell ring‐spun yarns

The study of yarn structure and related yarn properties has been the subject of much research. However, the study of the fiber packing density, which has practical significance for a number of yarns and their characteristics, has been limited to circular yarns because of the disordered yarn structure. In this paper, the fiber packing density of lyocell ring‐spun yarns is determined with the image analysis method. This method does not have any limitation with regard to the fiber cross‐sectional shape. The effect of yarn count, twist factor, spindle speed, traveler weight and front roller diameter on the fiber packing density in the yarn cross‐section is analyzed. The results of this paper and the data published in other scientific works are in good agreement.     

Investigation of the fastness properties and color values of cotton fabrics knitted from ring spun and Sirospun® yarns

Sirospun yarn production is a new approach to produce two‐folded and twisted yarns. This method integrates the spinning and folding action in a single step. Therefore, it may have some important advantages such as simplicity of the process, lower production costs, lower investment, space saving, etc. The purpose of the study is to compare the color fastness and colorimetric properties of sirospun yarn, single and two‐folded ring spun yarns produced by same cotton fiber blend. Therefore, three reactive dyes were applied at 1% omf (on mass of fabric) depth of shade to the single jersey fabrics which are produced by sirospun yarn, single and two‐folded ring spun yarns at three different counts. The examination of color coordinates of undyed and dyed samples on CIELAB color space shows that undyed sirospun fabrics show slightly higher whiteness than both undyed single and two‐folded ring fabrics for all three yarn counts. Also, the color strength values of the samples are determined as slightly different for all three dyes. The experimental studies show that sirospun yarns have no disadvantages with respect to conventional folded and twisted yarns when their fastness properties were compared.     

Influence of Dorlastan® draft and yarn count on the elastic recovery of the Dorlastan® core spun yarns following cyclic test

Elastic recovery is one of the most important mechanical properties especially of clothing applications. This property is more and more significant when the textile structure contains elastane filament and has significant elasticity. In this study, we investigate the effect of the Dorlastan® draft and yarn count on the elastic recovery of cotton-covered Dorlastan® core spun yarns. These yarns are used as weft yarns in denim fabrics. Dorlastan® core spun yarns with different counts 100, 50, and 25 tex, with different elastane drawings and with the same twist factor are used. Our test results revealed that the Dorlastan® ratio and yarn count are important factors in influencing the elastic recovery.     

Genetic algorithm‐based detection of the layout of color yarns

In this paper a novel method based on a genetic algorithm is proposed to recognize the layout of color yarns of yarn‐dyed fabric from the color pattern. The principle of a genetic algorithm is described first, and then the theories of roulette wheel selection method, crossover operation, and mutation operation are explained with the practical problem. Elitist selection is used to search for the correct result of the layout of color yarns. Some new chromosomes are added to the new generation in the genetic algorithm to avoid the local optimization. The repeat element of the layout of color yarns is then detected with period extraction. The repeat element of color pattern with the layout of color yarns is output together. Experiments on some color patterns recognized from actual yarn‐dyed fabrics, some color patterns simulated manually, and some color patterns including error color information of floats prove that the method proposed in this paper is effective for detecting the layout of color yarns from the color pattern of yarn‐dyed fabric, and it has a fault‐tolerance ability to some degree.     

Magnetic cotton yarns – optimization of magnetic properties

In this paper, we present the effect of ferrite percentage content and electric current intensity passing through the electromagnet coil on magnetic properties (saturation induction, residual induction, and coercive field) of magnetic staple yarns. Also, we present a method for obtaining magnetic yarns by direct coating with magnetic powder (barium ferrite). The aim of the study is to determine the optimal processing factors that can affect the performance of magnetic characteristics using an experimental design for second-order model. The results show that an increase in ferrite percentage content is influencing the saturation and residual induction more than an increase in applied current intensity. The increase in saturation and residual induction is due to the higher content of ferrite powder from the magnetic solution that adheres on the yarn surface. The higher is the value of coercive field, the larger is the force needed to completely demagnetize the magnetic yarn.     

Comparison of the gel-forming ability and gel properties of α-lactalbumin,lysozyme and myoglobin in the presence of β-lactoglobulin under high pressure

α-Lactalbumin (α-La) and lysozyme (LZM) each contain four disulfide bonds but no free SH group, whereas myoglobin (Mb) possesses no disulfide bond or free SH group. In this work, the pressure-induced gelation of α-La, LZM and Mb in the absence and in the presence of β-lactoglobulin (β-Lg) was studied. Solutions of α-La, LZM and Mb (1–24%, w/v) did not form a gel when subjected to a pressure of 800 MPa and circular dichroism analysis revealed that both α-La and LZM are pressure-resistant proteins. In the presence of β-Lg (5%, w/v), however, a pressure-induced gel formed for α-La and LZM (each 15%, w/v) but not for Mb (15%, w/v). One- and two-dimensional SDS-PAGE demonstrated the disulfide cross-linking of proteins was responsible for the gelation. Although α-La and LZM are homologous and have the same disulfide bond arrangement, the texture and appearance of the gels formed from α-La/β-Lg and LZM/β-Lg were markedly different even when induced under the same experimental conditions. Microscopic analysis indicated that phase separation occurs during the gelation of LZM/β-Lg but not during the gelation of α-La/β-Lg. NMR relaxation measurement revealed that the association of water molecules with the protein matrix in the α-La/β-Lg gel is tighter compared to that in the LZM/β-Lg gel. These results indicate that the gel-forming ability of a globular protein under high pressure is related to the primary structure of the protein, and that the gel properties depend on the cross-linking reaction and on the phase behavior of protein dispersion under high pressure.     

Flame retardant,anti-static and wear comfort properties of modacrylic/Excel®/anti-static PET blend yarns and their knitted fabrics

Abstract

This study examined the flame retardant, anti-static properties, and wear comfort of knitted fabrics made from three types of yarns composed of modacrylic, antistatic PET, cotton, and Excel^® fibers. A limit oxygen index (LOI) above 28 was observed in the two types of modacrylic knitted fabric specimens made from the Excel^®-included and cotton-blended yarns. The Excel^®-included modacrylic knitted fabric showed superior flame retardant properties to the cotton blended and 100% cotton ones. The anti-static properties of the two types of modacrylic knitted fabrics imbedded with 3?wt. % of antistatic PET fibers were observed experimentally and compared with the anti-static property of the 100% cotton fabric by rubbing with wool and cotton fabrics attached to the measuring apparatus; the Excel^®-included modacrylic knitted fabric showed better anti-static properties. Regarding the wear comfort, quick perspiration absorption, and fast drying properties of the Excel^®-included modacryl knitted fabric was superior to those of the cotton blended and 100% cotton ones. The thermal conductivity of the Excel^®-included modacrylic knitted fabric was lower than that of the cotton blended and 100% cotton ones. This was attributed to the lower intrinsic thermal conductivity of the Excel^® than cotton fibers, and the higher porosity and fabric thickness of the Excel^®-included fabric than the cotton blended and 100% cotton fabrics. The water vapor permeability of the Excel^®-included modacrylic fabric was lower than that of the 100% cotton one. In addition, the Excel^®-included modacrylic fabric appeared to have an inferior tactile hand compared to the cotton blended and 100% cotton fabrics because of its less extensibility, lower compressibility, higher bending and shear rigidity.     

Influence and comparison of emerging techniques of yarn manufacturing on physical–mechanical properties of polyester-/cotton-blended yarns and their woven fabrics

Abstract

In this study, the physical–mechanical properties of ring spun, ring compact, rotor and air-vortex yarns were investigated. The study was carried with yarn having linear densities of 24.4 tex and 36.7 tex, which were then converted to woven fabrics. The ring spun yarns have higher values of strength but also with higher strength irregularities. Extra-ordinarily low hairiness was observed in air-vortex yarns due to its unique yarn formation technique. The deviation rate (DR) of yarns have correlation with the mass spectrogram of respective yarns obtained from USTER Tester 5. Rotor and air-vortex yarns exhibited higher coefficient of friction. The woven fabrics made from ring spun yarns exhibited higher tensile and tear strength with higher elongation at break. The fabrics made from air-vortex yarns have very good pilling grade due to less protruding fibres on their surface and good structural integrity.     

Fabrication of poly(vinylidenefluoride‐co‐hexafluoropropylene) nanofiber yarns by conjugate electrospinning

Conventional electrospinning is an efficient method to fabricate polymer nanofibers which are usually collected as non‐woven mats. Recently, in order to fabricate a nanofiber yarn, conjugate electrospinning has been developed using coupled spinnerets applied with two high electrical voltages of opposite polarities In this paper, poly(vinylidenefluoride‐co‐hexafluoropropylene) (PVDF‐HFP) nanofiber yarns are prepared by conjugate electrospinning. The effects of the concentration and delivery rate of polymer solution and the distance between coupled spinnerets on the structure of PVDF‐HFP nanofiber yarns are investigated. The structure of the nanofiber yarns is observed by scanning electron microscopy (SEM). The mechanical properties of the nanofiber yarns are measured by electronic fiber strength tester. The results show that the PVDF‐HFP nanofiber yarn consists of a large number of nanofibers aligned well along the longitudinal axis of the yarn, and the nanofibers have diameters ranging from several hundred nanometers to a few microns. The diameter of nanofibers in yarns increases with the increase in the polymer concentration, which significantly affects the structure of nanofiber yarns. The PVDF‐HFP nanofiber yarn electrospun from the polymer solution with a concentration of 45% has the highest tensile strength of 0.25 cN/dtex and an elongation of 180.13%.     

Application of air‐jet nozzle in short staple Siro spinning system

With the objective of reducing the hairiness of Siro spun yarns, two types of air‐jet nozzle differing in the angle of sub‐holes and suitable for an air vortex ring spinning system were designed and fabricated. The performance of the JetSiro spinning system on short staple fiber materials and the effects of the different parameters on the hairiness of JetSiro spun yarns, such as nozzle pressure of compressed air, distance between front roller nip and inlet of nozzle, and nozzle structure, were investigated using the Taguchi method. The physical properties of JetSiro spun yarns with those of conventional Siro spun yarns were compared. The results show that the parameters, air pressure and distance between front roller nip and inlet of nozzle have the strongest and weakest effect on yarn hairiness. In addition, the optimum spinning conditions were determined. The application of the air‐jet nozzle exhibits significant reductions in yarn hairiness of 40%. The results revealed no significant effect of the air‐jet nozzle on the yarn tensile properties and evenness.     

Stability and degradation of the high‐intensity sweeteners: Aspartame,Alitame, and Sucralose

Abstract

More than 170 million Americans consume low‐calorie foods and beverages. The interest of the consumer in low‐calorie foods that contain alternative sweeteners has grown. Currently, non‐nutritive high‐intensity sweeteners, aspartame and sucralose have been approved for use in the United States. Another sweetener, alitame, used in other countries such as Australia and China has not been granted approval for use in the States.

The paper reviews the stability and degradation products of high‐intensity sweeteners, aspartame, alitame, and sucralose.     

Influence of ι-carrageenan, pectin, and gelatin on the physicochemical properties and stability of milk protein-stabilized emulsions

This study evaluated the stability of bilayer emulsions as a function of secondary layer composition and pH. Primary emulsions were formulated with 5% soybean oil, 1% protein from nonfat dry milk (NDM) powder as emulsifier and ι-carrageenan (ι-carr), low-methoxyl pectin (LMp), high-methoxyl pectin (HMp), or gelatin as secondary layers. ζ-Potential values increased for each emulsion as the pH decreased, with ι-carr emulsions being consistently more negatively charged than primary emulsions and significantly more stable. ζ-Potential values were not always correlated to emulsion stability. Gelatin secondary emulsions at pH 3 and HMp secondary emulsions at pH 7 were unstable due to the presence of depletion flocculation. In addition, LMp secondary emulsions stability at pH 7 might be due to calcium bridging, which increased the emulsion's viscosity. Overall, the stability of NDM emulsions was improved when ι-carr and LMp were used as secondary layers at pH 7 and 5, and when ι-carr and HMp were used as secondary layers at pH 3. Increased stability of these systems can be attributed to a second homogenization step used to formulate the secondary emulsions and to the presence of Ca(+2) in the NDM. Results from this research show that the stability of bilayer emulsions is driven by the presence of depletion flocculation, droplet charge, droplet size and distribution and viscosity. PRACTICAL APPLICATION: The use of everyday ingredients (nonfat dry milk powder, gelatin, pectin, and carrageenan), which are understood and accepted by the average consumer, creates label-friendly products that are the wave of the future. Stable emulsions can be formed using these ingredients at various pH. Understanding the stability and how the pH impacts the physicochemical characteristics and stability of these emulsions will enable manufactures to use ordinary ingredients to create healthier products (for example, low-fat dressings, sauces, dips, and beverages).     

Two‐way prediction of cotton yarn properties and fiber properties using multivariate multiple regression

This paper explains the feasibility of two‐way prediction by developing direct models relating fiber to yarn and reverse models relating yarn to fiber using multivariate methods simultaneously. These models evaluate the dependencies of cotton yarn properties on fiber properties and vice versa with minimum random errors and maximum accuracy. To this end, cotton fiber properties were measured from rovings carefully untwisted. An HVI system and an evenness tester of premier were used to measure the various properties. The samples of cotton yarns (108 samples) produced yarn counts ranging from 16 to 32 Ne with optimum twist factor. In this study, effective variables were selected by multivariate statistical test (m‐test). Then, multivariate analysis of variance (MANOVA) was used for evaluating the significance of obtained models. Next, the optimal separate equations were determined through multivariate multiple regression. After solving the linear equation system, a reverse model was achieved. By selecting fiber properties and machine factors as appropriate variables, the relative importance of these factors was also investigated. The results showed that the obtained equations were significant at the significance level α = 0.01.     

Comparison of IgA,TNF-α and surface tension of the tear film in two different times of the day

PurposeThe main goal was to study the biochemical composition of the tear film in two different times of the day.MethodsTear samples were collected from 10 individuals, non contact lenses wearers, from the university population without pathologies. To assess daily variations in the tear film, samples were collected twice in the day, one early in the morning and another in the evening using capillary tubes. Tear protein profile was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), tumor necrosis factor α (TNF-α) and immunoglobulin A (IgA) were quantified by Enzyme-Linked ImmunoSorbent Assay (ELISA). Tear film stability was obtained through measurements of Non-Invasive Break Up Time and tear surface tension was measured by obtaining the Langmuir isotherms.ResultsThe stability of the tear film was higher in the morning than in the afternoon; corresponding to a higher value of surface tension in the afternoon. Protein electrophoresis tear profile is variable during the day as IgA concentration decreased from morning to afternoon (p < 0.05). TNF-α concentration also decreased, but there were not significant statistical differences (p = 0.089).ConclusionWe concluded that there are daily variations in the composition and properties of the tear film, indicating that changes occur without being caused by contact lenses wear or by the presence of ocular and systemic pathologies. Presence of TNF-α is not a direct indication of inflammatory pathology, since this cytokine was identified in relatively high amounts in subjects without inflammatory pathology.     

Flow behavior and functional properties of barley and oat water‐soluble β‐D‐glucan rich extractions

Flow characteristics and functional properties of water‐soluble β‐glucan rich extractions prepared from hulled barley, hulless barley and oats were investigated. Rheological behavior was studied using a coaxial viscometer over shear rates of 3.0‐ 1312s^?1. The shear rate‐shear stress data followed the power law and Herschel‐Bulkley models. The flow behaviour index values varied from 0.31‐0.97, indicating mildly to highly pseudoplastic nature of the aqueous solutions of β‐glucan rich extractions. The pseudoplasticity for the aqueous solutions increased with increasing concentration of extractions. The hulless barley β‐glucan rich extractions showed higher pseudoplasticity, consistency index, and yield stress values; absorbed less water and exhibited higher fat absorption and oil emulsifying properties than those of the hulled barley and oats. There was no discernible influence of fat contents on functional properties of the concentrates. Dough development time, arrival time, stability and softening of the dough were negligibly affected with addition of various β‐glucan rich extractions to the flours. Supplementation of β‐glucan rich extractions desirably increased the baking absorption of the flours. Bread with improved loaf quality could be obtained using various β‐glucan rich extractions upto a level of 1.00% (w/w), especially, from those of hulless barley cv. PNB 5.     

Comparison of fabrics thermal properties between bulking wool and regular wool北大核心

This essay measures the fabrics' thermal properties between bulking wool and regular wool within the same grams per square meter, then finds that the warm-feeling of bulking wool fabric is stronger, and cool-feeling is weaker than regular wool fabric. Within double-board test, the heat resistant property of bulking wool is much better, and within single-board test the bulking wool fabric's heat resistant property is superior to regular wool fabric, but the difference between them diminishes. This fact reveals that wind resistant of bulking wool fabric is not so good, thus it should be utilized with lining. At the same time, a formula is concluded between the thermal property and thickness and air permeability. According to the results of the measurement, we can find that the properties of textile do not depend on fibers completely, and on account of the production technology on some level.     

Changes in physico‐chemical and rheological properties of rice during flaking

Hydration, solubility, pasting and rheological properties of roasted‐parboiled rice and flakes were examined in comparison to raw rice. There was an increase in the hydration capacity, swelling power and solubility during roasting‐parboiling of rice as a result of gelatinization of its starch. Flaking caused further increase due to damage of starch by application of mechanical force. The changes were higher in flakes from roller‐flaker as compared to those from edge‐runner. Pasting characteristics of flour slurries in Rapid Visco Analyzer showed a typical profile for pregelatinized products viz. a higher initial viscosity but a lower peak viscosity for roasted‐parboiled rice and flaked rice than for raw rice. The viscosity curves and flow curves of the products over a wide range of shear rate indicated a non‐Newtonian, pseudoplastic behaviour for all the samples. All samples showed typical hysteresis loop in their viscosity curves indicating their thixotropic nature. Flakes from roller‐flaker exhibited lower viscosity but more thixotrophy indicating higher starch breakdown in them than in edge‐runner flakes, which seemed to have more of heat damaged starch.     

Ring frame process parameters and fabric comfort. Part I – low-stress mechanical properties of fabrics

Influence of ring frame process parameters, namely twist multiplier of yarn, spindle speed and ring frame draft, on some of the yarn characteristics has been studied. The low-stress mechanical characteristics of woven and knitted fabrics made out of these yarns have also been reported in the present paper. Yarn packing factor, which is directly related with the yarn diameter, has direct impact on fabric comfort related characteristics. All the studied ring frame process parameters, i.e. yarn twist, ring frame draft and spindle speed, have inverse effect on the yarn diameter, which means the yarn diameter reduces with the increase in one of the process parameters by keeping the other two parameters constant. The impact of draft on reduction in yarn diameter is found to be higher as compare to other two parameters. All these ring frame process parameters have significant impact on other yarn parameters also. The increase in yarn twist, spindle speed and draft result in increase in flexural rigidity, unevenness and imperfections of yarn and decrease in yarn hairiness. All the low-stress mechanical properties, i.e. tensile, shear, bending, compression and surface, of both woven and knitted are affected by the above ring frame parameters. The thickness of fabrics changes with the yarn compactness, i.e. with the reduction in yarn diameter. The study revealed that by changing the above ring frame process parameters, it is possible to manipulate the fabric handle characteristics without changing the fabric constructional parameters.     

Aii analysis of the spinning and performance of new fancy yarn based on Siro spinnin北大核心CSCD

The fancy yarn has become a research hotspot al home and abroad because of its special appearance and rich color changes.In order to enrich the variety of fancy yarns, based on Siro spinning, this paper used rubber-covered back roller with grooves on its surface to spin new Siro fancy yarns and explained the spinning mechanism of new Siro fancy yarns.With the spinning parameters and materials being the same, a test was carried out on a TH 598 J ring throstle, and new Siro fancy yams and ordinary Siro yams were spun separately.The longitudinal structure of the yarns were observed and analyzed, and their linear density, tensile property, evenness and hairiness index were tested and compared.The test results showed that the longitudinal appearance of the yams showed floral changes.There was little difference between ordinary Siro yarns and the new Siro fancy yarns in breaking strength, elongation at break, evenness and hairiness. © 2021 China Silk Association. All rights reserved.