Effect of fibre diameter and cross-sectional shape on moisture transmission through fabrics

The current work incorporates an experimental study on the effect of fiber cross sectional shape and fibre diameter on moisture transmission properties of the fabric. Water vapour transmission of the fabrics was measured using the PERMETEST. In plane liquid flow through the fabric was measured using a gravimetric in-plane wicking tester and vertical movement of liquid along the fibres against gravity was also observed using a vertical wicking tester. With the change in shape factor and fibre diameter, it is seen that with increase in fibre specific surface area wicking rate through fabric increases, whereas water vapour permeability of the fabric reduces.     

Effect of heat setting parameters on some properties of PLA knitted fabric

This article reports the outcome of a study conducted for examining the effect of heat setting parameters on some properties of PLA knitted fabric. Three heat setting parameters, namely, treatment time, treatment temperature, and tension, were considered for optimizing the heat setting process with fabric shrinkage after dyeing and color yield as the evaluation factors. Experimental results revealed that lower shrinkage and higher color yield can be achieved when: (i) heat setting time = 60 s; heat setting temperature=130 oC; and tension=0%. After that, the PLA knitted fabric was treated under the optimum heat setting condition and was dyed with 1% depth disperse dye, which produced a better dyeing result. However, the handle of the heat set PLA knitted fabric, as measured by Kawabata Evaluation System for Fabric (KES-F), became stiffer and more resistant to shearing movement and had worse drape and bending recovery ability, while the appearance became fluffier and rougher.     

Development of moisture transition ability on porous complex structured woven fabric with convergence of pattern,porosity, and plasma technology

A porous complex structured woven fabric was manufactured to maximize the moisture transition ability of the prepared fabric by increasing the absorptive property of the fabric through surface modification using plasma, which is a dry modification method. Porous single and complex structured woven fabrics were produced by applying pattern, porosity, and plasma technology, including fabric patterning based on the sheath/core complex structure, the formation of porosity by removing the weft thread or warp thread, and hydrophilic surface treatment using plasma and the improvement in water absorption of different fabrics by the porous and plasma treatment was investigated. Therefore, two different types of fabrics were prepared. One is the porous single structured FAB-SINGLE fabric which was taken out in the direction of the Polyester (PET) warp thread of a general single structure to form a porous. Another is FAB-COMPLEX fabrics that the water-soluble polylactic acid (PLA) yarns with a 1.7 to 2.0 times longer absorption distance than that of PET yarns were inserted into the weft threads, and the PLA yarns were dissolved in a solvent to form the porous complex fabric. And then the physical properties and water absorption of the two types of fabric were compared after the plasma treatment. The results showed that when the FAB-SINGLE fabric, which has porosity induced by the removal of the warp threads in a certain gap, was plasma treated for 5 min, the contact angle was decreased to the extent that a measurement of the contact angle was impossible, whereas the fabric that had not undergone a plasma treatment had a contact angle of 123.6 o. The contact angle of the FABCOMPLEX with porosity caused by the dissolution of the PLA yarns was reduced from 76.8 o to 0 o after 3 minutes of a lowtemperature plasma treatment, indicating that the hydrophilic property was increased. In addition, the water absorption measurements showed that the absorption height was increased from 2.3 cm of the fabric sample that had not been treated with plasma to the highest absorption height of 8.3 cm, suggesting that the water absorption also increased with the improvements in moisture transition ability by the plasma treatment. The physical tensile strength of the fabrics was not changed by the plasma treatment, despite the changes on the fabric surface, suggesting that the combination of double complex structures and the plasma treatment helped improve the water absorption.     

Impregnation of zinc oxide mediated chitosan nano-composites on polyester fabric for performance characteristics

Present study dealt with the fabrication of chitosan/zinc oxide nano-composites (CZNCs) using a facile preparation method. The structural features of nano-composites were investigated by using advanced analytical techniques. The developed nano-composites exhibited hexagonal structural pattern with an average particle size of about 51 nm. The developed CZNCs were dispersed in 2-propanol and applied on polyester by using the pad-dry-cure method. The treated fabric specimens were characterized for surface, functional and textile properties including antibacterial activity and (ultra violet) UV- blocking. The nano-composite treated polyester fabric exhibited durable antibacterial, UV- blocking and textile properties with fair whiteness index.     

Development of a Human-Clothing-Environment simulator for dynamic heat and moisture transfer properties of fabrics

A vertical skin model with two detachable environmental chambers was developed to simulate a Human-Clothing-Environment system and to evaluate heat and moisture transport properties of textile materials under severe conditions and during transient states. The construction of the system was described and data reproducibility and accuracy of the instrument were verified by using PEG treated nonwovens. Also advantages over a traditional static type experiment were demonstrated based on a series of experiments.     

Effect of enzyme treatment and wood pulp variation on physical characteristics and fabric hand of lyocell fabrics

The purpose of the research was to examine the effect of three different levels of enzyme treatment on the physical characteristics and the end-use suitability of the lyocell fabrics made with four different types of commercial wood pulp. The appropriate enzyme concentration for obtaining an optimum as well as consistent physical characteristics and fabric hand trait was 3 g/l for the concentration levels tested in the present investigation. Weight loss was more affected by higher enzyme concentration than other physical properties. H2 was least affected by enzyme treatment for all three physical properties and fabric hand. 5 g/l concentration exhibited little difference from 3 g/l in the physical characteristics, whereas the KES-FB values indicated a significant loss of fabric hand in most PHVs with the 5 g/l concentration level. Among different garment parameters, all four fabric types were relatively inappropriate for the men’s slacks (MS) fabric due to the lower hand value of koshi required by the MS parameter. However, despite the relatively low koshi values, high fukurami values required for men’s dress shirt (MWDS) resulted in the highest THV among the four garment parmeters. The four fabric types, which represent the usage of four different wood pulps, in general seem to exhibit a higher applicability to women’s winter thin dress (WWTD) than women’s winter suit (WWS) garment parameter.     

Electrical characteristics and signal transmission characteristics of hybrid structure yarns for smart wearable devices

Twisted Copper Filaments (TCF) have been made by a yarn covering process in order to transmit signals and powers for electronic textiles. The 560 den. poly urethane filaments were covered in S-twist direction by urethane-coated copper wires. Two TCF twisted in Z direction were further covered in S direction by PET filaments to make final hybrid structure yarns (HSY). The HSY prepared was proportionally increased in apparent resistance along with measurement length, and showed resistivity of 0.00414 Ω·m. The number of ply was critical in terms of resistance variation, showing a linear increase of resistance with ply number. The twist factor, however, was not so significant without a slight decrease for severe twist level. Resonance Frequency, S11 (reflection), S21 (transmission) were measured and compared in order to examine the feasibility of applying to electrical signal transmission for wearable textiles. As expected, amplitude of resonance frequency was significantly decreased mainly due to increase of capacitance caused by length increase. It has been shown that S11 and S21 has been increased and decreased, respectively due to increase of transmission distance. While resonance frequency has been kept along with the ply number, S11 and S21 were decreased and increased, respectively according to decrease of copper fiber. Final filaments were found to be changed in resonance frequency mainly due to the change of di-electricity and thus capacitance caused by PET covered on it. It have been concluded that while resonance frequency was primarily determined by filament length and dielectric constant of covering yarns, S11 and S21 were mainly determined by measurement length and ply number.     

Effect of moisture transfer on texture uniformity of cooked rice after heat preservation with electric rice cooker

The texture uniformity of rice cooked by electric rice cooker (ERC) will deteriorate during the heat preservation process. In this study, the uniformity of rice texture and water dynamic were investigated by means of physical property analyzer and low-field nuclear magnetic resonance technique. The water content, distribution and migration in rice were compared to illustrate the effect of heat preservation mode with different temperature at pot cover. The middle-upper layer of rice was drier and harder after 24 h of heat preservation in conventional mode, while the outer-upper layer of rice absorbed water, swelled or even broken. The difference of water content between the two parts was 6.55%, and the difference of hardness was 333.31 g. The relaxation signal indicated that the binding force between immobile water of the two parts and the rice matrix became weaker after heat preservation. By adjusting the heat preservation mode with higher temperature of the cover, the moisture content difference between the internal-upper layer and the peripheral upper layer was decreased to 0.39% after 24 h of heat preservation, and the hardness difference was reduced to 2.99 g. These mean that the texture uniformity of the whole pot rice after heat preservation was maintained.     

The effects of humidity on the surface modification of wool fabric through atmospheric pressure plasma jet

Current research was carried out on hydrophilic wool fibers at three different humidity conditions through atmospheric pressure plasma jet (APPJ). Samples were taken to evaluate surface microscopic morphology, surface roughness, directional friction effect (DFE), and surface chemical composition. The scanning electron microscope (SEM) and fiber friction coefficient test (FFT) results show that wetting pretreatment has significant effect on surface etching and DFE, but very limited effect on surface roughness. Allwörden reaction and X-ray photoelectron spectroscopy (XPS) results reveal that extra moisture changes C, O, N, S contents and their related characteristic functional groups, therefore increases etching degree on wool fiber surface scales. It was concluded that APPJ treatment is effective in processing wool fiber with high moisture contents.     

新型油料种子水分检测方法研究

发现并应用了油料种子在无线电频率范围内的导电浴盆效应,提出一种新的油料种子水分快速检测方法,研制了相应的仪器,仪器已在我国粮油行业推广使用,解决了长期以来粮油现场水分快速、准确测量的难题。     

基于Grid算法的棉田雨后土壤水分时空变化特征研究

为探索雨后棉田土壤水分时空变化特征,在2行棉花下方土壤采用网格取样法获得不同位点含水量数据,并基于Grid算法分析不同维度土壤含水量变化特征.结果表明:在棉行附近20 cm内,10 cm深的表层土壤的含水量随雨后时间增加呈拟合优度较高的开口向上抛物线形,30～50 cm深的土壤含水量与雨后时间呈相关性较强的负相关关系;...     

Assessment of the surface roughness of cotton fabrics through different yarn and fabric structural properties

The effects of some yarn properties (i.e. type, count, twist level, ply number, unevenness and crimp) and fabric constructional properties (i.e. cover, thickness and balance) on surface roughness values of cotton woven fabrics were investigated. A general overview of the results showed that surface roughness values of fabrics were affected from yarn and fabric properties and the effects were related to fabric balance, fabric cover (not cover factor), fabric thickness and crimp values of yarns in fabric structures. Surface roughness values of fabrics decreased as yarn fineness and yarn twist levels increased but as yarn ply number decreased. Also, surface roughness values gradually decreased from open-end yarn constituting fabrics to combed yarn constituting fabrics. Results showed that different properties of yarns caused changes in yarn crimps in fabric structure and also governed the changes in fabric balance, as well as changes in roughness of fabric surfaces. The changing properties of yarns and impact of these properties on fabric construction affected the formation of cotton fabric surfaces from smooth to coarse.     

The effect of fabric balance and fabric cover on surface roughness of polyester fabrics

The effects of fabric balance and fabric cover on surface roughness values of textured polyester woven fabrics with different constructional parameters were investigated. The warp yarn properties (type, count and warp density) were kept constant while the effect of variation in weft yarn density and weave pattern were studied. Measurements were conducted on pre-treated white fabric samples and the results assessed in relation to their constructional properties. A general overview of the results showed that surface roughness values of polyester fabrics affected by fabric balance and fabric cover and the effects were related to fabric thickness, yarn densities, yarn crimp, positioning of yarns in fabric structure. A change in weave pattern from sateen to plain increased the fabric balance and fabric cover, but decreased the surface roughness. Similarly, an increase in weft density increased the fabric balance and fabric cover, but decreased surface roughness. In order to produce fabrics with smooth surface properties yarn density should be increased, yarn float lengths decreased, cover of fabrics increased and fabric balance improved.     

A new approach to evaluate the effect of moisture on heat transfer of thermal protective clothing under flashover

It’s urgent to investigate moisture effect on thermal protection of thermal protective clothing in simulated fire scene as accurately as possible. The current bench top tests can’t evaluate thermal protective performance (TPP) of fabrics under microclimate with high temperature and relative humidity (RH). In this paper, to well investigate effect of different RH under microclimate on thermal protective performance of flame-retardant fabrics exposed to flashover, a new modified TPP testing apparatus was developed. It consisted of a typical TPP tester and RH adjustable microclimate chamber. Three kinds of air gaps under fabrics were also employed to simulate different spaces between skin and clothing. The results showed that the temperature increment under microclimate of 35 % RH was highest, and that of 95 % RH was lowest. There was significant temperature difference found among above three adjusted environment. Time required of temperature rise to 12 oC highly prolonged as RH became higher. It could be deduced that the effect of RH on heat transfer became significant as air gap increasing; if the air gap width still increased, the moisture effect diminished. The newly developed testing apparatus could be well used to evaluate the moisture effect on thermal protective performance of flame-resistant fabrics.     

Study on antibacterial and comfort performances of cotton fabric finished by chitosan-silver for intimate apparel

The fabric used for intimate apparel is widely required to have excellent antibacterial and comfort performances. In order to improve its antibacterial ability, this paper studied chitosan-silver finishing on the cotton knitted fabric. The study indicates that the chitosan-silver attached to the fabric exhibits excellent antibacterial action against the typical bacteria of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureu). The anti-bacterial mechanism of chitosan-silver against E. coli and S. aureu were investigated. To guarantee its prominent comfort performance, measurements were made on the finished fabric of its air permeability, water vapor transmission, hydrophily, surface friction and bending ability against the control fabric, which is currently used for intimate apparel. The antibacterial and comfort performances were compared between the tested fabrics. The results show that the air permeability and the hydrophily of the finished cotton fabric are significantly better than the control one, while the water vapor transmission, the surface friction and the adjustable rate remain similar to each other. The bending rigidity of the finished fabric is slightly better due to the attachment of chitosan within accepted threshold. The dual compounding theory of chitosan-silver proves to be useful for a higher synergistic effect of anti-bacteria, lower whiteness degradation and overall optimization of comfort performance. This dual compounding theory of chitosan-silver is valuable for improving antibacterial and comfort performances of intimate apparel.     

Abiotic transmission of Rice yellow mottle virus through soil and contact between plants

The roles of guttation fluid, irrigation water, contact between plants and transplantation into contaminated soil in the transmission of Rice yellow mottle virus (RYMV) were assessed. RYMV presence and infectivity were tested by Enzyme-Linked Immunosorbent Assay (ELISA) and by inoculation to susceptible rice cultivar BG90-2. The virus was readily detected in guttation fluid collected from infected rice plants. Transmission tests from this fluid led to high disease incidence (86.6%). Irrigation water collected at the base of infected plants growing in pots was less infectious, as inoculations led to disease incidences below 40%. No virus was detected and could be transmitted from field-irrigation water. Up to 44% healthy rice plants whose leaves were in contact with those of infected plants became infected but, no transmission occurred through intertwined roots. Transplantation of rice seedling into virus-contaminated soil also led to plant infection. However, virus survival in the soil decrease rapidly and infectivity was completely lost 14 days after soil contamination. Altogether, these results indicated that high planting densities of rice are likely to favour secondary spread of rice yellow mottle disease. Transplantation of rice seedlings not earlier than 2 weeks after soil preparation should prevent soil transmission of the virus. Although guttation fluid is highly infectious its contribution to virus infectivity in irrigation water is negligible as field-irrigation water was not found to be an infectious source for RYMV.     

Mathematical modelling of combined diffusion of heat and mass transfer through fabrics

This study presents a theoretical and experimental investigation of the process of drying of fabrics on a continuously moving flat plate. A mathematical model is developed for heat and mass transfer analysis of fabric in the impingement dryers. For simplicity, it is assumed that during the drying period of the fabric has porous media and on the drying surface the vapour pressure of the evaporating liquid remains at a quasi-saturated value corresponding to the temperature of the liquid. Using the model, the calculated transient fabric temperatures in the impingement dryers agree well with the experimental results.     

Effects of material properties and fabric structure characteristics of graduated compression stockings (GCS) on the skin pressure distributions

Graduated compression stockings (GCS) have been widely used for the prophylaxis and treatment of venous diseases. Their gradient pressure function largely related to their fabric structure and material properties. By combing fabric physical testing and wear trials, this study investigated the GCSs fabric structure and material properties at different locations along the stocking hoses, and quantitatively analyzed the effects of fabrics on skin pressure longitudinal and transverse distributions. We concluded that, Structural characteristics and material properties of stocking fabrics were not uniform along the hoses, but a gradual variation from ankle to thigh regions, which significantly influenced the corresponding skin pressure gradient distributions; Tensile (WT, EM) and shearing properties (G) generated most significant differences among ankle, knee and thigh regions along the stocking hose, which significantly influenced the skin pressure lognitudinal gradient distribution. More material indices generating significant gradual changes occurred in the fabric wale direction along stocking hose, meaning that materials properties in wale direction would exert more important impact on the skin pressure gradient performances. And, the greater tensibility and smoother surface of fabric in wale direction would contribute to put stocking on and off, and facilitate wearers’ leg extension-flexion movements. The indices of WT and EM of stocking fabrics in series A have strong linear correlations with skin pressure lognitudinal distribution, which largely related to their better performances in gradual changes of material properties. Skin pressure applied by fabric with same material properties produced pronounced differences among four different directions around certain cross-sections of human leg, especially at the ankle region; and, the skin pressure magnitudes at ankle region were more easily influenced by the materials properties, which were considered to be largely related to the anatomic structure of human leg.     

高水分蒸煮挤压小麦混合粉的研究

食品蒸煮挤压技术是多学科交叉所产生的一门高新技术,蒸煮挤压作为一种高温短时的加工方法,能够将输送、压缩、混合、蒸煮、杀菌、成型等多种操作单元同时完成。本实验优化了双螺杆机的加工工艺参数,DS56-Ⅲ型双螺杆挤压膨化机挤压腔内限流区的温度在125℃．含水率为40％、螺杆转速为215rpm,该条件下得到的最好产品膨化度为2．51,经过蒸煮挤压后的食品含水率为35％～37％。