毛条中折钩纤维的表达

采用Almeter长度分析仪对毛条中纤维长度进行了测量,通过对纤维长度特征值和短绒率的分析,讨论了毛条成形中纤维折钩(隐性损伤)对纤维长度特征值的影响.实测证明纤维的隐性损伤可以用长度特征值来表达,而短绒率是一较敏感的指标.     

毛条成形中长度损伤的演变与表征:(1)纤维的断裂——显性损伤

在成条加工中纤维长度会损伤或变短,其中纤维的断裂——显性损伤是纤维损伤的基本部分。采用2次从纤维束头端反复制取一端整齐的纤维丛试样(C试样),可获得分析纤维显性损伤的长度特征值。基于长度特征值建立的差异率和损伤率指标,可有效地表征纤维的这类损伤。实测证明毛条加工各工序都有长度损伤,平均值为8.763%,综合等效长度的变短可达86%以上;而较为敏感和稳定的长度表达指标应该取短纤维率和根数加权平均长度。     

毛条中纤维长度分布特征及损伤的定量估计

利用纤维长度测量仪(Almeter-100)和双向取样与2次整理的方法,实测了毛条中纤维的长度分布特征.通过正、反向和无折钩试样纤维长度分布的对比,讨论了纤维的断裂引起的长度显性损伤和纤维弯折所致的隐性损伤,并对毛条加工中纤维长度的显性和隐性损伤做了定量分析.     

绢纺梳绵对丝纤维损伤的探讨

本文对梳绵机损伤纤维的因素作分析,以圆梳落绵与开茧绵张作梳绵试验比较,提出梳绵机梳理绢丝纤维的合理长度,使之有利于纤维分梳和减少纤维损伤,提高精绵质量和制绵梳折。     

绢纺梳绵工艺探讨——新老结合的制绵工艺路线

三、新老结合工艺效果分析(一) 梳折高,能充分利用高级原料从表6中三种制绵工艺总梳折的数据对比表明,新老结合工艺路线的总梳折最高为48.24%。比新工艺的梳折提高6.68%;比老工艺圆梳梳理二道的总梳折提高6.24%,工艺效果显著。从Ⅰ号落绵采用新工艺路线分析,B_2精绵(条)梳折可得到16.03%;而Ⅰ号落绵采用老工艺路线C_2精绵的梳折为10.38%。采用不同工艺路线B_2梳折可提高5.65%。分析其原因,是由于新工艺加工落绵,纤维(束)较蓬松,白点松散,纤维经过切断,超长纤维少,在轻定量梳理时,梳理过程比较顺利,梳理力也减小。使纤维损伤少,白点细小,纤维长度较长,圆梳机     

降低精梳机纤维损伤的技术措施

随着高速精梳机的普遍使用,精梳机损伤纤维是不可避免的,但如果采取有效的技术措施,纤维损伤的程度就会有所减轻。根据笔者多年的生产实践,主要从以下几方面入手解决。(1)提高生条纤维伸直度。由纤维弯钩伸直理论可知,后弯钩的伸直效果随牵伸倍数的增大而增加。适当增大道夫至压辊各区间的棉网张     

漂白和染色加工对羊绒纤维的损伤及对后道工序的影响

羊绒与羊毛相比,细、短、鳞片层薄,加工过程中,很容易被损伤而失去天然、独特的柔软、光滑特性.羊绒纤维在漂白和染色过程中,化学助剂及工艺本身对其都会造成损伤,使其长度变短,细度变粗,手感变涩,从而影响羊绒纱的可纺性、织造性能及成品手感.文章通过分析,提出了一些保护和减少加工过程对羊绒纤维损伤的观点,对实际生产有一定的指导作用.     

绢纺梳绵纤维状态分析

在开松梳理过程中,绢纤维逐步被拉断,在梳绵绵条中,纤维形成一定的长度分布,其中也包含了由此而产生的大量短纤维、绵粒和纤维弯钩。本文试作一简略的分析,希望为提高绢纺梳绵新工艺的梳折和质量提供借鉴。(一)梳绵绵条中纤维长度分布     

基于图像处理技术的弯钩纤维表征

为了减少因弯钩纤维形成的棉结,纺出优质纱,针对弯钩纤维提出伸直度、弯钩程度、弯钩角等相关指标,利用CCD摄像机采集棉网中的示踪纤维图像,经过MATLAB数字图像处理技术得到适于特征参数提取的纤维图像,对弯钩纤维的特征参数进行提取分析,为减少弯钩纤维提供了技术支持。研究发现纤维弯钩程度和弯钩长度与弯钩角密切相关。     

试析纤维照影仪的起始距离和跨距长度

纤维照影仪是快速测量纤维长度的光电仪器,其纤维照影仪的基本原理是:将纤维试样随机梳取在梳子或梳夹上,利用光电管作为传感元件,测量狭窄的扫描光束透过纤维试样须丛后的光强度随梳子移动的变化关系,从而反映了伸出握持点的长度与纤维试样须丛在该长度处厚度的函数关系,进而求得各项长度指标。起始距离是开始扫描处离夹持点(梳子根部)的距离。起始距离为什么不能为零?Y146型棉纤维光电长度仪(以下     

开松梳理中的羊毛纤维损伤

梳理部件与羊毛纤维的相互作用非常复杂,会造成羊毛纤维损伤.使用电子显微镜观察和分析纤维长度变化可以了解毛纤维在开松梳理中的损伤程度.通过研究得出,毛纤维在断裂前,表面结构已经发生细微的损伤,出现裂缝、龟裂、躯干受损等现象.毛纤维在开松梳理中受梳理元件的作用,促使纤维弯曲变形,并迅速回复,同时还受到表面剪切、卷曲等外力作用,纤维表面形态被破坏,也造成毛纤维的各种损伤.     

Study on spliced yarns of different spinning technologies. Part II: structural characteristics

A detailed study on structural parameters of splices of viscose staple fiber yarns made from ring, rotor, and air-jet spinning technologies are reported in this paper. All the yarns each had six different color tracers with 0.3% of total fibers. A three variable three-level factorial design approach proposed by Box and Behnken has been used to study the interactive effect of splicing parameters. The splicing parameters, such as splicing length, duration of splicing air blast, and splicing air pressure were varied to prepared spliced yarn samples. Splices were introduced at all these levels for the three different technologies. This paper deals with the structural characteristics of splice portions, i.e. splice diameter, helix angle, splicing coefficient of fiber (SCF), and fiber overlapping coefficient (FOC). The structural characteristics, such as splice diameter, helix angle, SCF, and FOC, are significantly affected by the different splicing parameters (i.e. splice length, duration of the opening air blast, and splicing air pressure). Different types of yarns (ring-, rotor-, and air-jet-spun) show different trends of structural characteristics with splicing parameters. Part I of this paper deals with the mechanical characteristics of spliced portion.     

Morphology of the Bagasse Fibers Obtained from the Elaboration Process of Mezcal and Effects on Their Tensile Properties

The morphology of the cross-section and longitudinal-section of bagasse fibers of Agave angustifolia Haw from the elaboration process of mezcal were investigated and tensile tests were performed in function of the diameter (0.20–0.79 mm), gauge length (10, 15 and 20 mm) and strain rate (5–50 mm/min). The cross-section of the fibers is ribbon-shape like with dislocations and the longitudinal section has mechanical damage in its surface. The ultimate tensile strength (14.83–86.51 MPa) and Young’s modulus (0.20–1.26 GPa) are influenced by the diameter and the strain rate, while the strain at failure (16–26%) is influenced by the gauge length. These results are discussed in light of information on relationship between morphology and tensile properties of natural fibers and possible effects of the elaboration process of mezcal.     

An investigation of the sampling bias of the beard method as used in HVI™

The beard method is used for sampling cotton fibers to generate fibrograms from which length parameters can be obtained. It is the sampling method used by the Uster High Volume Instrument (HVI^?). A fundamental issue of this sampling method is its bias since the mathematical computation to obtain length parameters is quite different. There have been different assumptions regarding the bias of the beard sampling method. In our experiments, we have seen discrepancies in measurements that cannot be explained as length‐biased or unbiased, especially in the short fiber region. We report a fundamental research, including experimental and theoretical analysis, and computer simulations, that reveals the bias due to this sampling method. We find that the beard sampling method as used in HVI is not completely length‐biased; fibers sampled by using this method are similar to the original fibers except in the short fiber region. Short fiber content (SFC) of the sampled fiber is lower than that of the original fiber, and this difference is inherently introduced by the sampling method.     

Correlation between Pod Shape Traits and Its Fiber Quality of Wild Calotropis Gigantea

Seed fiber in the Calotropis gigantea (C. gigantea) pods is the most valuable component and can be developed into textile material. Cultivating high-yield and high-quality seed fibers for C. gigantea is one of the critical preconditions for its textile industrialization. In this paper, pods picked from wild C. gigantea plants were used as the experimental materials. The fiber length distribution of the pods was studied. The pod characters (pod shape, single pod weight, fiber weight per pod and seed number per pod, etc.) and the crucial quality characteristics of seed fibers (length, diameter and strength) were tested. The correlations between them were analyzed. The results show that the fiber lengths at the tip, the petiole and the middle part of the pods are significantly different: the fibers from the two sides of the middle part are the longest and more uniform. The pod shape is closely correlated with the fiber length, fineness and strength: longer pods have longer fiber length, smaller length variation and larger fiber diameter, and the percentage of low strength fiber (single fiber strength <1.2 cN) is significantly lower compared to smaller pods. Cultivating C. gigantea with large size and heavy pods will improve the seed fiber yield and the fiber quality.     

柔性纺织纤维基超级电容器研究进展

为促进纤维基超级电容器在柔性能量存储领域的应用,以纺织纤维原料为类别,对高性能纤维(碳纳米管纤维,石墨烯纤维)、天然纤维、合成纤维基超级电容器的研究进行综述。在此基础上,对不同类型的纤维基超级电容器性能分析对比,总结各种纤维基超级电容器的优缺点。结果表明,高性能纤维基超级电容器的纤维结构、传荷位阻、离子扩散速率决定了纤维比能量及循环寿命,但该类型纤维基超级电容器受限于纤维材料的力学性能,后续织造较为困难;天然、合成纤维可满足后道纺织工艺对纤维的力学要求,易与纺织品结合成为整体,其储能大小受活性物质结构、密度、电荷传递协同效应影响较大。最后,针对柔性纤维基超级电容器研究存在的问题进行说明并对未来需要攻克的重点难点进行分析及展望。     

烟草浆高浓与低浓打浆效果的比较

分析了目前造纸法再造烟叶生产中普遍采用的烟草浆高浓打浆存在的缺陷,阐述了低浓打浆“两级打浆”工艺,并从纤维特性和成纸物理性能两个方面对烟草浆高浓与低浓打浆的效果进行实验和对比.结果表明,低浓打浆有效地解决了高浓打浆存在的缺陷;与高浓打浆相比,低浓打浆的纤维长度提高了10.8％、宽度下降了17.8％、粗度降低了9.5％,扭曲度、切断率和柔软度等指标都明显下降.