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91.
真丝绸抗皱整理的探讨 总被引:2,自引:0,他引:2
研究了DEA交联剂对真丝绸的整理工艺,分析了影响整理效果的若干因素,确定了合理的工艺条件。结果表明;真丝绸经DEA事理可使湿折皱回复角从200度提高到270-275度,并具有良好的耐洗性。本文还对DEA整理真丝绸的抗皱机理进行了初步探讨,证明了DEA交联剂和丝素大分子发生了交联反应。 相似文献
92.
最大界面剪切应力的估算与芳纶复合材料界面粘结的表征 总被引:2,自引:0,他引:2
研究以估算的最大界面剪切应力,表征芳纶Kevlar49复合材料的界面粘结。依据Greszczuk模型和单纤维拔出实验数据估算最大界面剪切应力,研究纤维表面处理和基体改性对界面粘结的影响。选用不同活性基团表面的芳纶Kevlar49和两种耐高温树脂基体组成强粘结界面体系的研究结果表明,实验数据与理论曲线拟合很好。 相似文献
93.
94.
The work presented in this paper details the development of a finite element (FE) model of a soccer ball, allowing for a greater understanding of the performance of soccer balls under dynamic conditions that are representative of play. The model consists of composite shell elements that include a hyperelastic strain energy potential equation to define the latex bladder layer and a plane stress orthotropic elastic material model to define the anisotropic woven fabric outer panels. The model was validated through a series of experimental impact tests whereby the ball was impacted normal to a rigid plate at an inbound velocity of approximately 34 ms−1 (76 mph), with each impact recorded using high speed video (HSV) techniques. It was found that the combined effects of ball design and panel material anisotropy resulted in impact properties such as coefficient of restitution, contact time, deformation and the 2D shape taken up by the ball at maximum deformation, to vary with pre-impact ball orientation. The model showed good agreement with the measurements, and its ability to represent the effects of anisotropy in ball design. 相似文献
95.
MARKTRAN II is an interactive FORTRAN IV program that computes Markov transition probabilities for two-dimensional patterns. The pattern is represented by a series of discrete states at each point on a rectangular grid composed of square cells. Transition probabilities in eight directions are computed. MARKTRAN II is useful for numerically describing the fabric of patterns that possess any degree of anisotropy. Geological applications include analysis of rock fabrics, outcrop patterns of geological maps, and variations in ore grade expressed as discrete states. 相似文献
96.
Fiber composite materials have unique, advantageous mechanical properties that have made them highly desirable in a range of industries. In particular, 3D woven-fiber composites are highly resistant to delamination compared with laminated 2D woven-fiber composites and have been adopted in various advanced products. This paper focuses on the design of 3D woven-fiber composite products and proposes a flattening simulation method for designed 3D models with constant thickness. The proposed method estimates the shape of a flat material and the fiber directions in the 3D model design; deformation phenomena of 3D woven-fiber materials are also considered in order to improve the accuracy of the proposed method. CT images are used to compare the simulation results with the actual deformation of 3D woven-fiber materials and confirm the ability of our method to effectively design the fiber direction base on the 3D model and to estimate the shape of flat materials. 相似文献
97.
A theoretical model, describing thermal degradation behavior of cotton fabrics that exposed to a constant radiant heat flux, is proposed in the paper. The model describes thermal and oxidative degradation of cotton fabric under the oxygen‐containing atmosphere and considers pseudo‐bi‐component separate‐stage kinetic process. Both exothermic and endothermic reactions are included in the decomposition process. At present, gas phase oxidation reactions are not included. Comparison with experimental results demonstrates that the predictions of the mass loss rate and temperature profile with these cotton fabrics are in agreement with the experiment. Effects of thermal radiation and ambient oxygen concentration on decomposition have also been investigated. The gas phase temperature is also predicted by the present numerical model. Results from numerical model will help contribute to a better understanding of the ignition mechanism of flame‐resistant cotton fabrics used for fire safety garments. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
98.
Abdulghani A. Al‐Farayedhi 《国际能源研究杂志》2001,25(6):555-561
This paper presents an experimental study leading to the understanding and modelling of the effect of air speed and its direction on flame propagation in tent fabrics in addition to fire propagation in a tent camp. The study was conducted on burning fabrics of different densities subjected to wind speeds ranging between zero (stagnant) and 1.4 m s?1. Moreover, several air directions with respect to the flame were considered in the study to cover the cases of vertically upward, downward, horizontally aiding and opposing, and inclined directions. These cases were used in simulating actual flame propagation in a tent. It is found that there is a logarithmic relation between the time of burning a tent and air speed and the density of tent fabrics. Two different types of fabric are considered; waterproof and non‐waterproof. It is also observed that the surface flame temperature is invariant with air speed or fabric density and it reaches about 650°C. The results show that denser fabrics require more time for burning. The maximum flame propagation speed is observed for vertically upward flame concurrent with air direction. On the other hand, minimum flame propagation is observed for vertically downward flames opposing the air direction. A model is derived for predicting the time required for flame propagation in a known camp area. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
99.
钱纪芳 《西北纺织工学院学报》2008,(1):28-34
运用简单的集合原理研究了纺织物指别词汇的语义场,发现其中的上下义关系的类属指别词和多项分类对立关系的种属指别词可以用9种不同的翻译策略加以翻译,其中的部分语义重叠特征的同义聚合关系可以构成纺织物指别词翻译的一词多译雏度,另外,归纳了9类与纺织物指别词相关的修饰性范畴词,共同构建了纺织物指别词翻译的能产性网络,用于翻译纺织物的基本指别词汇。 相似文献
100.
针刺毡/聚酯树脂手糊层板力学性能 总被引:1,自引:0,他引:1
本文简要介绍了针刺短切玻璃毡/不饱和聚酯树脂手糊层板的力学性能。 相似文献