苎麻牵切纺纱的牵切工艺探讨

本文主要分析了新型苎麻牵切机各项工艺参数对最终麻条质量的影响,主要包括皮辊加压、牵切区隔距、预牵切区隔距、牵切区牵伸倍数.     

苎麻牵切原理及牵切区断裂点分布的研究

本文主要分析了苎麻单纤维在牵切区内运动及断裂的过程，通过试验考查了断裂点的分布情况。     

苎麻牵切原理及牵切区断裂点分布的研究

本文主要分析了苎麻单纤维在牵切区内运动及断裂的过程,通过试验考查了断裂点的分布情况.     

苎麻麻条牵切工艺初探

通过对苎麻纤维长度及其分布，超长、倍长纤维对苎麻纺纱的不利影响的分析，提出了采用牵切提高苎麻纤维长度整齐度，减少超长、倍长纤维的加工技术。     

牵切苎麻在棉纺设备上的纺纱初探

对苎麻长麻纺（复精梳）工艺中的苎麻预并条和头道精梳条进行牵切,然后分别将其在棉纺设备上进行并条、粗纱和细纱加工。探讨牵切纱断裂强度与捻系数的相互关系,并对比分析牵切纱与常规纱的质量。结果表明,牵切纱临界捻系数αt 在405左右,苎麻牵切精梳纱的条干、粗细节、棉结及3 mm以上的毛羽与苎麻常规精梳纱的接近,且断裂强度优于苎麻常规精梳纱的。     

改善苎麻牵切质量的工艺研究及其成纱质量分析

本文针对苎麻牵切纺牵切条中硬条、集束多的问题,探索了几点改善措施:如加装针辊,可使牵切条中硬条减少18%左右,"集束"降低25%左右;对喂入的精干麻进行预牵伸,可使牵切条中硬条减少26%左右,"集束"降低31%左右;对牵切条进行针梳后,硬条减少20%左右,"集束"减少32%左右;并比较分析了苎麻牵切纱和常规纱的成纱质量,结果表明:苎麻牵切纱质量显著优于常规纱.     

苎麻麻条牵切工艺初探

通过对苎麻纤维长度及其分布,超长、倍长纤维对苎麻纺纱的不利影响的分析,提出了采用牵切提高苎麻纤维长度整齐度,减少超长、倍长纤维的加工技术.     

苎麻牵切纺纱与常规纺纱质量对比

苎麻常规纷纱过程中纤维平均长度为100mm左右,但其中存在着大量的超长、倍长纤维,且纤维长度严重参差不齐,本文对苎麻精干麻进行牵切,得到平均长度为85mm左右、长度整齐度明显改善的牵切苎麻条,并通过生产实践与同一环境下常规苎麻纺的各道工序的质量进行对比分析.     

亚麻牵切中纤维断裂过程和规律的研究

本文分析了亚麻纤维在牵切区中断裂的过程，并通过实验研究了其断裂的规律，给出了粗略估计牵切后纤维平均长度的方法。     

亚麻牵切中纤维断裂过程和规律的研究

本文分析了亚麻纤维在牵切区中断裂的过程,并通过实验研究了其断裂的规律,给出了粗略估计牵切后纤维平均长度的方法.     

Mechanical properties of wool fiber in the stretch breaking process

Short wool fibers obtained by the stretch breaking process can be blended with cotton fibers and processed in a cotton spinning system, which has a high production rate. For the structural property of the wool fiber after stretch breaking, the diameter and length of the wool fiber were measured as a function of time. The diameter of the broken fibers was finer than the diameter of untreated fibers. The fiber diameter at the break point was the finest and was more irregular than the original fiber. The broken fiber showed mechanical properties of increased modulus, decreased breaking strain, and increased breaking strength.     

The structural configuration and stretch property relationship of high stretch bandage fabric

The high compression bandages need to be designed or selected based on their ability to apply high levels of pressure with minimum stretch and maintain the same over a period of time. This can be achieved if the factors controlling this behaviour are optimised to get the desired performance. The efficiency of different bandages to provide sustained pressure varies because of differences in their structure and constituent material type as the fibre type, yarn structure and the structure of the bandage. In this paper the structure and stretch relationship of different high compression bandage materials have been studied which would help to design and evaluate the bandage performance during and after application on the limb. The influence of structure of the bandage in terms of design pattern/weave, linear density and number of inlaid elastic yarn in the high stretch bandages along with their mechanical behaviour has been investigated. It has been found that different bandages although commercially sold under the category of high compression bandages show quite varied tensile and relaxation behaviour depending on their structure and constructional parameters. The bandage sample with coarser high elastic yarns show low fabric growth, high breaking load and high elastic recovery values. The presence of higher number of high stretch inlay yarns and a tighter structure enhances the power of the bandage to cling on the limb for a longer period of time and be suitable for reuse. The bandage performance depends on the optimisation of these parameters to get desired efficacy of the compression system.     

Performance of neural network algorithms during the prediction of yarn breaking elongation

Yarn breaking elongation is one of the most important yarn quality characteristics, since it affects the manufacture and usability of woven and knitted fabrics. One of the methods used to predict the breaking elongation of ring spun yarn is artificial neural network (NN). The design of an NN involves the choice of several parameters which include the network architecture, number of hidden layers, number of neurons in the hidden layers, training, learning and transfer functions. This paper endeavors to study the performance of NN as the design factors are varied during the prediction of cotton ring spun yarn breaking elongation. A study of the relative importance of the input parameters was also undertaken. The results indicated that there is a significant difference in the types of transfer and training functions used. Of the two transfer functions used, purelin performed far much better than logsig function. Among the five training functions, the best training functions in terms of performance was Levenberg-Marquardt. The study of the relative importance of input factors revealed that yarn twist, yarn count, fiber elongation, length, length uniformity and spindle speed, were the six most influential factors.     

Handle,fit and pressure comfort of silk/hybrid yarn woven stretch fabrics

Hybrid yarn was produced by twisting silk with nylon covered lycra yarn. Silk of 20 D in warp and hybrid yarn in weft was woven to develop lustrous woven stretch fabrics for sari blouse. Silk and hybrid yarn fabrics were produced in three different weaves namely plain, crepe and sateen. An in-depth study was carried out to understand the effect of weave on thermal comfort; low stress mechanical properties, total hand value and stretch properties. Nine blouses (3 samples× 3 figures) were constructed from three different woven stretch materials for fit assessment and objective pressure comfort test. The effect of fabric weave, low stress mechanical properties, total hand value and stretch properties on fit and pressure comfort of silk/hybrid yarn stretch fabrics were analyzed. Sateen weave silk/hybrid yarn stretch fabric shows higher total hand value, stretch properties and better thermal comfort properties. Sateen and crepe weave stretch fabrics provided good fit. Sateen weave fabric exerted lower clothing pressure value in the range of 3-12 mmHg at all body locations in standing position and in different postures.     

小麦根系细胞学观察体系的构建和应用

为给小麦根系的生物学研究提供技术支撑,基于激光扫描共聚焦显微镜(laser scanning confocal microscope, LSCM)和光切片技术,通过优化制片体系和调整观察参数,构建了小麦根系胚根的横向和纵向细胞结构观察技术体系,并利用该体系对小麦品种农大1108、小偃22、烟农19号、碧蚂4号和西农88的主胚根根冠、分生区、过渡区、伸长区和成熟区进行了连续观察和比较。结果表明,供试材料的根冠和分生区长度、成熟区内部的不同组织细胞大小在材料间均存在显著差异,但分生区横向细胞结构和过渡区长度在材料间无明显差异。     

A Novel Method to Fabricate High Strength Nanofiber Filaments: Morphology,Crystalline Structure,and Thermal and Mechanical Properties

Wet electrospinning is a simple and efficient method to manufacture continuous nanofiber filaments. However, polyacrylonitrile nanofiber filaments collected using a static water bath are limited for application in certain areas due to their low degree of alignment and breaking stress values. To improve these properties, a novel countercurrent flowing liquid bath collector was combined with a multi-needle electrospinning device. The morphologies, crystalline structures, thermal behaviors and mechanical properties of filaments fabricated under different countercurrent bath liquid motion conditions were investigated. In addition, the forces acting on the nanofibers in the bundling triangular zone under countercurrent liquid bath motion were analyzed. The results showed that the average nanofiber diameter of the filaments decreased with an increase in bath solution motion forces. The maximum alignment degree and breaking stress of the nanofibers were 85 % and 0.63 cN/dtex, respectively, achieved using a liquid flow rate of 80 ml/min and water inlet diameter of 6 mm. The alignment degree of the assembled nanofibers in the bundling triangular zone could be increased by 57 % when using a countercurrent flowing liquid compared with a static liquid bath.     

模拟犁底层条件下春玉米叶片形态发育及衰老表征

通过模拟犁底层和模拟打破犁底层处理进行试验,研究犁底层对春玉米叶片形态发育及衰老表征,明确犁地层对东北春玉米生产易引发早衰的机理。结果表明,模拟犁底层处理的第8片到第11片叶玉米叶片长度以及第13片叶到第20片叶叶片宽度均小于模拟打破犁底层处理,达到极显著水平;从5片叶全展开到小喇叭口期,模拟犁底层处理比模拟打破犁底层处理晚发育9 d;模拟犁底层处理缩短了中部叶片的持绿时间6 d;模拟犁底层处理相对模拟打破犁底层处理降低了开花期绿叶面积及开花后相对绿叶面积,生产上采用农业机械深松打破犁底层可延缓后期叶片衰老进程。