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1.
为研制车船等壳体所用的轻质、高强复合板材,选用超高分子量聚乙烯(UHMWPE)短纤维纱,制备成单层经纬为120根/(10 cm)的平纹组织,采用多组经纱持续更替交织层的方法制成2L(1+0)型、4L(2+1)型、6L(3+2)型3种多层角联锁结构织物,采用扦插芯棒、模压成型方法制成菱形蜂窝状的热固性环氧树脂基中空板,并与2块真空吸液法制成的面板组成“三合一”复合板,同时测定了复合板材的结构特征及其平拉、平压和弯曲性能。结果表明:3种类型复合板的密度均远小于水的密度,其中6L(3+2)型最小,为0.48 g/cm3;复合板层数越多,环氧树脂越难渗透尤其是在中空板菱形交叉点处,复合板平拉、平压、抗弯曲强度则呈现递增,制成的6L(3+2)型复合板试样平压强度可达到1.03 MPa。 相似文献
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Yarn-dyed fabric is often woven from warp and weft yarns in the same color depth to ensure a uniform color appearance. The difference in color depth between warp and weft tends to result in the uneven color of the yarn-dyed fabric. This article aims to establish a color tolerance for yarn-dyed fabric that can be woven with a qualified color appearance but from the warp and weft yarns in different color depths. A total of 27 yarn-dyed fabric samples in three color series (red, yellow, and blue) were evaluated by using the yarn-dyed fabric from warp and weft yarns in the same color depth of 2% (on weight of fabric, owf) as the standard. Visual assessment and instrumental measurement of color were carried out to establish the color tolerance ellipse that was defined as CMC (Color Measurement Committee) color differences (2:1) of no more than 1.00. It was found that the color strengths (K/S) and color differences (ΔECMC(2:1)) of these fabric samples for each color series had linear relationships with the color depths of warp and weft yarns. The color tolerance ellipses indicated that, even though the warp and weft yarns had an apparent color difference, they could be woven in fabrics with relatively uniform color appearance and meet the requirements for yarn-dyed fabric. This work provided valuable insight into the production of qualified yarn-dyed fabrics from unqualified dyed yarns. 相似文献
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Under the circumstance of perceptual consumption, it is still challenging to grasp consumer's emotions and demands due to the large search space, diversified preferences, and easy fatigue of consumers. To reduce user fatigue and enlarge search space, a novel method was presented to design and optimize the pattern of yarn-dyed plaid fabric using the isolation niche genetic algorithm and rough set theory. Each pattern was encoded as a chromosome based on the real number code. The population was initialized and evolved using INGA to maintain the diversity. The rough set theory was adopted as the fitness function of isolation niche genetic algorithm to extract the consumer's demands. After multiple evolutions, a large set of practical patterns of the yarn-dyed plaid fabric are obtained. Experiments were carried out by 24 testers of different ages and genders. The results prove that the proposed method based on the isolation niche genetic algorithm and rough set theory is feasible and effective, supplying references to the designer. 相似文献
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针对机匣包容性问题,提出Kevlar平纹织物本构模型的拟合方法,分别采用单层壳、多层壳、层合壳三种有限元建模方式对Kevlar织物软壁包容环弹道冲击过程进行模拟,发展了机匣包容性仿真分析模型。结果表明,多层壳模型和层合壳模型的计算结果更准确,并且可以通过调节摩擦因子使仿真结果与试验结果更接近。在此基础上研究了撞击点位置和弹体入射姿态对弹体剩余速度的影响。结果表明:在较小偏移距离内,撞击点的位置对剩余速度的影响可以忽略不计;滚转角和俯仰角对剩余速度影响较小,而对于偏航角,当角度大于30°时,剩余速度会随着角度的增大明显呈下降趋势,且弹体出射姿态也会发生明显变化。 相似文献
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Khurram Shehzad Akhtar Ali Afzal Wardah Anam Zulfiqar Ali Tanveer Hussain 《纺织学会志》2020,111(4):555-564
AbstractIn 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. 相似文献
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针对传统相变微胶囊后整理法制备蓄热调温纺织品时存在制备工序繁杂、效率低等难点,开发了一种简便快捷的后整理法。选用相变蜡、聚氧乙烯辛基苯酚醚-10(OP-10)乳化剂和水性聚氨酯为主要组分,经高剪切乳化制备蓄热调温功能整理剂,利用浸轧—焙烘方式对棉织物进行整理。优化乳化剂用量、相变蜡与聚氨酯配比及焙烘温度,并测定整理后棉织物及背心的蓄热调温性能。结果表明:当OP-10质量分数为5%,相变蜡与聚氨酯的质量比为1.5∶1,焙烘温度150 ℃时,整理剂在纤维表面原位成膜形成包裹纤维的蓄热调温薄膜,从而赋予棉织物蓄热调温功能;整理后棉织物具备蓄热调温功能,由其所制作的背心具有显著的蓄热调温功能。 相似文献