Effect of Splice Marking on Fabric Roll Planning

Minimising the fabric loss during spreading can reduce the total production costs of garment manufacturing. Although marker planning is a major determinant of material utilisation, considerable savings on materials also will be made from the area of spreading loss. In the spreading process, it is general to have variance on the fabric yardage between each fabric roll, and the number of splice markings on each cutting lay is also varied. This paper aim to study how the fabric roll planning and the number of splice marks of a cutting lay will affect the material usage in the spreading process. By using a genetic algorithm approach, the amount of fabric to be saved by optimising the fabric roll sequence was derived by comparing the best arrangement and the worst arrangement of the fabric roll sequences of a cutting lay. The result of the study showed that both fabric roll planning and the number of splice marking have effect on the fabric loss. The findings could help the apparel manufacturer to reduce the     

机织物悬垂屈曲的数值模拟

开发虚拟服装试衣系统需模拟织物的悬垂和屈曲，而采用正交异性力学模型不适合织物．为此，笔者基于织物的细观力学模型，用有限元方法来模拟方形织物片铺在圆桌面上的悬垂和屈曲，该细观模型描述了织物由于其细观编织结构而特有的力学性质．织物片用8结点壳单元离散，这种壳单元被特别设计，能描述织物片在悬垂中发生的大转动．对织物片的屈曲模态进行了分析，对其后屈曲变形进行了计算，也进行了方形织物片的悬垂和屈曲实验．模拟结果和实验的观测结果很一致．该研究为虚拟服装试衣系统的开发奠定了基础．     

雨滴对降落伞织物垂直冲击的实验研究

为了研究多雨环境对降落伞开伞的影响机理,设计了液滴对降落伞织物垂直冲击的实验装置。依据降雨谱选择有代表性大小的液滴,由雨滴和降落伞的稳降速度确定了液滴的冲击速度范围在0.77~2.42 m/s之间,利用高速摄像机记录液滴对织物垂直冲击的动态过程,分析了液滴在织物表面的铺展特性。实验结果表明:当液滴冲击速度提高150%和214%时,反映液滴铺展特性的平均最大铺展因子分别增大64%和68%。此外,提高织物的预紧张力可以有效减弱液滴对织物冲击所造成的振动影响。     

长寿命连铸辊的堆焊材料和工艺开发

介绍了大型板坯连铸机连铸辊的工况特点、主要失效形式,阐述了连铸辊堆焊材料的研究现状和性能要求.在1Cr13NiMo堆焊材料的基础上,增加了功能合金元素,开发出新的堆焊焊带和匹配的烧结焊剂,新堆焊熔敷金属的组织、强度和冷热疲劳性能明显优于进口焊材;研究了不同堆焊层间温度和焊后热处理温度对堆焊材料性能的影响规律.结果表明,合理的堆焊层间温度和焊后热处理温度能够获得最理想的组织和机械性能;新型连铸辊的使用寿命优于国外同类产品.     

Study on Properties of Dynamic Heat-Moisture Transfer of Summer Fabrics

The skin heat loss(heat flow)of summer fabrics duringthe course of sweating--evaporating--drying is mea-sured by an apparatus specially made for the purpose.Itis pointed out that:the dynamic heat-moisture comfortcan be described by evaporating rate or time required fordrying out of a certain amount of sweat.The evaporat-ing rate is influenced by the hygroscopic property andthickness of the fabric,the larger the hygroscopicity ofthe fabric with the same thickness,the smaller the evap-orating rate of the perspirated sweat.     

纤维素酶在染整加工中的应用——牛仔布的高级后整理工艺探讨

为了改善牛仔布的外观和手感，并且减少生产加工中的环境污染，根据纤维素酶的作用原理，探讨了牛仔布生物法石磨的工艺，对不同纤维素酶的作用效果进行了对比与分析，并配合纤维素酶的处理选用了适当的柔软剂。经实验证明，经纤维素酶加工后的牛仔布，有良好的石磨效果，并且表面光洁，加工中无环境污染问题，配用适当的柔软剂后，不仅织物手感柔软，而且织物强力损伤小，产品档次明显提高。本实验中的工艺可供生产中使用。     

夏季服用织物动态热湿舒适性的影响因素研究

利用自制的织物动态热湿性能测试仪测定了不同透气性和不同原料的夏季服用织物在皮肤干燥-出汗-蒸发-干燥的过程中的皮肤热损失、微气候区温湿度变化的情况,研究了影响夏季服用织物动态热湿舒适性的因素,指出在外界风速较大或织物的透气量较大时,汗液蒸发是通过紊流扩散进行,由于汗液的快速蒸发,可能使人体产生冷感,此时不同织物的微气候区温湿度差别很小,当外界风速小或织物的透气性小时,汗液的蒸发通过分子扩散进行,此时微气候区的湿度主要受织物吸湿能力的影响,吸湿能力较强时湿度低,纯涤织物在出汗后,由于微气候区湿度较高,将使人产生闷热感,在出汗结束后降温较多可能产生冷感,不宜作为夏季服用织物,纯毛织物因吸湿放热多在出汗初期升温较高,不利于散热,夏季以穿着纯棉、涤棉、毛涤混纺织物的服装为宜.     

脱胶工艺对丝织物穿着性能的影响

本文讨论了脱胶工艺对真丝织物服用性能的影响,并测试了其服用性能最重要的指标,如:丝织物的白度、亮度、断裂强度、断裂延伸、动摩擦系数和粗糙程度等。实验结果表明:纯碱是真丝织物脱胶的主要用剂;丝织物的脱胶率与脱胶液内的纯碱浓度有关,但最好采用纯碱和表面活性剂作为混合脱胶剂;丝织物在纯碱2—3g/L 和油酸钠3g/L 溶液中脱胶1小时,所得白度、亮度较高,断裂强度和断裂延伸下降较少,并可减少丝织物动摩擦系数和降低其粗糙程度,改善其表面性能。     

甲基丙烯酸羟乙酯接枝改性真丝织物的研究

本文以甲基丙烯酸羟乙酯（HEMA）为单体，过硫酸钾为引发剂．对真丝织物进行接枝改性处理。探讨了不同处理条件对接枝效果及其真丝织物性能的影响。研究表明．选用合适的工艺参数对蚕丝织物进行接枝处理，在保持真丝绸原有风格的同时．可获得较好的改性效果。     

302矿床围岩蚀变与铀矿化的关系

储广山花岗岩体受郯庐断裂系遂川——热水走滑断裂带控制,区内塘湾断裂及一系列北西向断裂带发育,构成有利的成矿构造结,其中发现多个大型、超大型的铀矿田和铀矿床,其铀矿化受多因素控制,以构造、围岩和岩浆-热液活动为主,在时间上、空间上具有独特的展布规律,通过对该矿床的岩石、构造、矿体和围岩蚀变特征的分析,探讨了围岩蚀变与铀矿成矿的关系,为同类地区的找矿提供了依据.     

Study on the Factors to Influence Dynamic Heat - moisture Comfort of Summer Clothing Fabrics

In this paper, the factors to influence the dynamic heat - moisture comfort of summer clothing fabrics have been studied. It is pointed out that, when the wind speed outside is high, or the air permeability is very good, the sweat of human body will evaporate mainly through turbulent diffusion. Because of the rapid sweat evaporation, human body will feel cold, and then, the difference in temperature and humidity of the micro - climatic section will be very slight. On the contrary, when the wind speed outside is slow or the air permeability is unsatisfactory, the sweat of human body will evaporate mainly through molecular diffusion, and in this case, the humidity of the micro - climatic section will be depended on the hygroscopicity of the fabric, that' s to say, the better the hygroscopicity, the lower the humidity. It is difficult for pure wool fabric to loss heat because of its giving out much heat during the course of moisture - absorption in the initial stages of sweating. For pure polyester fabric,     

关于脆弱生丝织造性能的研究

将正常生丝、脆弱生丝、经柔软剂处理的脆弱生丝一起作为经丝上机织造,比较它们织造过程中断头、张力情况,并对织物的拉伸性能、染色性能作对比分析,结果表明:脆弱生丝经柔软处理后断头次数明显减少,织物强力有所增加,但与正常生丝一起染色存在色差.     

Evaluation of Fabric Pilling Using Light Projection and Image Analysis Techniques

A new instrument based on light projection and image analysis techniques for assessing fabric pilling is presented. This system can automatically detect the pills from the successive sections of the fabric surface, which can make up for the limitation of both the gray level image -analysis techniques and laser triangulab'on techniques. The test of a large number of worsted wool fabric samples shows that it can objectively characterize the degree of pilling by using fuzzy sets and has good accordance with human visual inspection.     

Measurement of the Average Molecular Weight of Cotton Cellulose Crosslinked by a Polycarboxylic Acid at Different pH Using Multiple Angle Light Scattering Photometer in a DMAc/LiCl Solvent System

Durable press finishing of cotton fabrics with polycarboxylic acid increases fabric wrinkle-resistance at the expense of its mechanical strength. Severe tensile strength loss is the major disadvantage for wrinkle resistant cotton fabrics. Tensile strength loss of cotton fabric crosslinked by a polycarboxylic acid can be attributed to depolymerization and crosslink of cellulose molecules. Measurement of the molecular weight of cotton fabric before and after crosslinked by polycarboxylic acids can offer a possibility of direct understanding of the depolymerization. In this research, a multiple angle laser light scattering photometer was used to determine the absolute molecular weight of cotton fabric treated with BTCA at different pH and then hydrolyzed with 0.5 M NaOH solution at 50℃ for 144 h. The results indicate that average molecular weights of cotton fabric treated with polycarboxylic acids at different pH are almost the same.     

红外光谱法用于织物防水剂合成的研究

利用红外光谱法对织物防水剂合成进行了研究，结果发现织物防水剂质量与合成中酯化过程有关。并采用自身内标比例法鉴定合成产品质量，为合成条件的选择，提供了可靠数据。     

基于空间相关性不同组构干热岩裂隙发育

基于以往对干热岩开发的研究,不难发现其主要赋存介质为花岗岩,而此类岩石的组构分布与裂隙发育关系对其开采能效有较大影响。鉴于此,针对花岗岩组构分布与裂隙发育规律的考虑。利用空间相关性函数构建出不同组构的花岗岩表面图像,然后利用离散元数值软件针对图像组构进行建模,结合多种室内试验对数值模型参数进行校准,并进行抗拉强度试验,将裂隙发育情况采用分形维数对进行分析。结果表明：(1)空间相关函数随机场随着其参数的变化能够有效表征岩石内部组构变化情况;(2)随着花岗岩试件组构分布的变化,试件的强度也随之变化;(3)裂隙发育的分形结果表明,矿物组构的不同导致破坏过程中破裂点数目和破裂点发育状态不同,从而对试件的强度产生影响。进而影响干热岩开发的工艺和热交换效率。     

无线网络中的高效空间-频率编码技术

循环延迟冗余技术(CDD)是OFDM系统中对抗码间串扰的一项重要技术.CDD在发送端采用多天线,不同天线采用不同的相位延迟,从而增加发送端等价的信道频率选择性.首先对CDD技术进行综合评述,然后分析了CDD中的最佳延迟选择,并和CDD技术和经典的Alamouti空时码进行性能比较.仿真结果显示最优延迟下CDD技术能达到更好的性能,并且对天线阵列的数目没有约束.     

地表热通量的变化对边界层热力对流卷的影响

以1995年8月14日在Florida观测(SCMS实验期间)的位温、水汽和风速等为初始化的大涡模拟结果,分析研究了边界层对流卷的发展及地表热通量对边界层热力对流卷的影响。分析了热力对流卷的位温、垂直速度及水汽混合比的关系。结果表明在边界层对流卷中,上升气流较暖湿,下沉气流较干冷。还研究了边界层对流卷的演变,结果表明当地表热通量增大时,对流会变得非常活跃,对流层发展的高度也会加深。而当地表热通量增大致超过对流卷维持的临界值时,已经无法观察出对流卷的线性特点。利用地表热通量对对流卷形成和消散的敏感性实验模拟结果,分析得出地表热通量改变时,对流卷的组织性和对流的强度发生的相应变化。减小地表热通量时,对流的强度明显减弱。对流卷的组织性较显著。增加地表热通量时,对流的强度增大,对流会变得很不规则,但当地表热通量太大时,已经看不到有组织的对流卷。研究结果表明对流卷的维持需要一定的地表热通量。     

循环荷载作用下新型钢筋套筒灌浆连接结构性能

为降低钢筋连接成本,利用普通无缝钢管通过冷滚压工艺加工了一种新型钢筋连接用灌浆套筒,并制作了12个钢筋连接接头试件,通过反复拉压试验及单向拉伸试验研究其连接结构性能.结果表明,该连接能够满足JGJ107-2010规定的强度及变形要求;接头经过反复拉压循环加载后,钢筋极限黏结强度较直接拉伸试件约降低10%;由于套筒的约束作用,钢筋套筒灌浆连接残余黏结强度大于极限抗拉强度的50%;套筒每端内壁环肋数量不宜少于3道,并应根据接头承载力要求的提高而适当增加.     

Wet Transfer Model of Woven Fabric

To investigate wet permeability of woven fabric, a wet transfer model of woven fabric is built up and by means of the model, the main factors which have significant influences on its wet permeability function, including liquid/ material contact angle, fiber diameter, fiber cross-section configuration, the number of fibers, yarn＇s twisting angle and woven density, are discussed. Finally it is derived from the argument that optimal design of wet transfer function of woven fabric can be obtained.