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Influence of the Structure of Seersucker Woven Fabrics on their Friction Properties

Abstract

Friction is defined as a force resisting a relative motion between two bodies in contact. The friction of a fabric on itself or on another fabric influences significantly a fabric’s performance and user’s utility comfort, especially the so-called sensorial comfort. Generally, the coefficient of friction is determined for a given pair of materials. The aim of the present work was to investigate the influence of the structure of the seersucker woven fabrics on their frictional properties. Three variants of the seersucker woven fabrics of different repeat of the seersucker effect were the objects of the investigations. Three measuring elements were applied: made of aluminum and steel and covered with silicone. The obtained results confirmed the influence of the pattern of the seersucker effect on the values of friction coefficient. It was also stated that there are differences between the friction coefficients measured in the warp and weft directions of the seersucker woven fabrics. Values of friction coefficient between the seersucker woven fabrics and measuring elements were the highest for the measuring element covered by silicone. These values were several times higher than the values of friction coefficient measured using the measuring elements made of aluminum and steel.

Open access
Preparation of Polypyrrole/Silver Conductive Polyester Fabric by UV Exposure

Abstract

In this study, polypyrrole/silver (PPy/Ag) conductive polyester fabric was synthesized via an in-situ polymerization method under UV exposure, using silver nitrate (AgNO3) as an oxidizing agent in the presence of sodium dodecyl benzene sulfonate (SDBS) and polyvinylpyrrolidone (PVP). The effect of the preparation processes on the properties of the conductive fabric was studied experimentally, and the optimal preparation process of the conductive fabric was obtained. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) showed the chemical structural properties of the PPy/Ag conductive polyester fabric. X-ray diffraction (XRD) confirmed the presence of silver nanoparticles in the prepared material. Furthermore, subsequent test results proved that the PPy/Ag conductive polyester fabric prepared by UV irradiation had good electrical conductivity and antibacterial property. The sheet resistance of the prepared conductive fabric was 61.54 Ω • sq−1.

Open access
Development of Mask Design Knowledge Base Based on Sensory Evaluation and Fuzzy Logic

Abstract

This article focuses on the development of the mask design knowledge base, which is expected to be applied in a personalized mask design system. To realize the proposed knowledge base, a perceptual descriptive space of the mask is first developed for the description of both functional and aesthetic perceptions of a mask. The mask ontology is also developed to form the mask element matrix. Mask design knowledge is expressed as the relationship between the perceptual descriptive space and the mask ontology, which is extracted by a group of experienced designers through a sensory evaluation procedure. This relationship is then simulated by fuzzy logic tools. The proposed knowledge base has been validated that it is reliable. The personalized mask design system can be further developed with the propose mask design knowledge base.

Open access
Effect of Temperature on the Structure and Filtration Performance of Polypropylene Melt-Blown Nonwovens

Abstract

By applying the simultaneous corona-temperature treatment, the effect of electret temperature on the structure and filtration properties of melt-blown nonwovens was investigated. Fiber diameter, pore size, thickness, areal weight, porosity, crystallinity, filtration efficiency, and pressure drop were evaluated. The results demonstrated that some changes occurred in the structure of electret fabrics after treatment under different temperatures. In the range of 20°C~105°C, the filtration efficiency of melt-blown nonwovens has a relationship with the change in crystallinity, and the pressure drop increased because of the change in areal weight and porosity. This work may provide a reference for further improving filtration efficiency of melt-blown nonwovens.

Open access
Kinematic Comparison of a Heald Frame Driven by a Rotary Dobby with a Cam-Slider, a Cam-Link and a Null Modulator

Abstract

The kinematics of the heald frame of a rotary dobby with two different modulator types are analyzed and compared. Kinematic mathematical models of the modulator main shaft, cam unit, and heald frame driven by the rotary dobby with a cam-slider modulator and a cam-link modulator were constructed based on two different cam contours derived from measured points on the conjugate cams of the two modulators. The motion characteristics of the two modulators and a null modulator, the cam unit, and the motion transmission unit are analyzed. The purpose of the present study was to establish the kinematic models, investigate the motion characteristics, and analyze their differences. At the same time, a calculation method for each motion transmission process was established and numerical models were developed. The results demonstrated that the two different modulators produce almost the same heald frame motion characteristics. Despite that both modulator types can be adapted to the requirements of a loom, the cam-link modulator can produce a more stable and reliable motion.

Open access
Quick Detection of Aldehydes and Ketones in Automotive Textiles

Abstract

This study was aimed to develop a quick detection method to test aldehydes and ketones in textiles in order to control the quality of automotive textiles in the development process from fabric production to end-use in vehicles. In this study, a pretreatment of samples was applied to simulate the actual environment of textiles used in vehicles. Collected volatiles were reacted with 2,4-dinitrophenylhydrazine and then eluted with acetonitrile tetrahydrofuran. The eluent was analyzed with high-performance liquid chromatography. Findings showed more than 90% volatiles could be detected in the established method; the lowest determination limit was 0.0297 mg/mL; and the lowest quantification limit was 0.0991 mg/mL, which meant sensitivity and capability of the method were high. Regression coefficients of linear models between volatile concentrations and chromatographic peak characteristics were >0.995, indicating that the method could effectively and efficiently determine the contents of volatiles in automotive textiles.

Open access
The Status of Textile-Based Dry EEG Electrodes

Abstract

Electroencephalogram (EEG) is the biopotential recording of electrical signals generated by brain activity. It is useful for monitoring sleep quality and alertness, clinical applications, diagnosis, and treatment of patients with epilepsy, disease of Parkinson and other neurological disorders, as well as continuous monitoring of tiredness/ alertness in the field. We provide a review of textile-based EEG. Most of the developed textile-based EEGs remain on shelves only as published research results due to a limitation of flexibility, stickability, and washability, although the respective authors of the works reported that signals were obtained comparable to standard EEG. In addition, nearly all published works were not quantitatively compared and contrasted with conventional wet electrodes to prove feasibility for the actual application. This scenario would probably continue to give a publication credit, but does not add to the growth of the specific field, unless otherwise new integration approaches and new conductive polymer composites are evolved to make the application of textile-based EEG happen for bio-potential monitoring.

Open access
Chapter 1. Stability of Hybrid Systems on Time Scale
Chapter 2 Stability of Hybrid Systems with Aftereffect
Chapter 3. Stability of Hybrid Systems in a Metric Space