精练对广西天然黄色家蚕茧性能的影响

研究了广西天然黄色家蚕茧的茧型、练减率,探讨了精练对其回潮率、拉伸性能的影响。通过观察SEM、傅立叶红外光谱、X-射线衍射图谱,分析精练对广西天然黄色家蚕丝晶态结构的影响,并与广西天然白色家蚕丝进行了比较分析。结果表明:天然黄色家蚕茧茧型较小,练减率为21.47%,精练前后回潮率分别为9.25%和7.85%,拉伸断裂强度分别为33.54 cN/tex和26.05 cN/tex,精练对天然黄色、白色家蚕丝的晶态结构影响均不显著。     

鲜茧生丝与干茧生丝含胶率试验比对

采集大量不同庄口的干茧生丝与鲜茧生丝进行含胶率试验和分布特征分析。结果表明,鲜茧生丝含胶率普遍较高,平均高于干茧生丝2.09%;干茧生丝与鲜茧生丝含胶率分布存在交叉重叠,重叠率为27.60%,非重叠率达72.40%,含胶率检测可以作为鉴别鲜茧生丝与干茧生丝的一个初筛手段;当生丝含胶率低于24.00%或高于26.00%时,鉴别正确率达到100%;当含胶率在24.00%~26.00%时,因干、鲜茧生丝含胶率测试值存在交集,需配合其他检测手段进行干茧生丝与鲜茧生丝的鉴别,有待进一步研究。建议鲜茧缫丝企业主动增加丝胶溶失率,以适应丝织工艺要求。     

鲜茧前处理工艺对缫丝及生丝性能的影响

为探讨鲜茧前处理方式对生丝性能的影响,选择干茧、冰冻茧为研究对象,采用真空渗透、煮茧(不煮茧)、立缫工艺生产35dtex(30/33D)生丝,按照织造要求进行浸泡处理,测试生丝的性能。结果表明:干茧生丝、鲜茧生丝的抱合性能良好,平均抱合次数均超过100次;浸泡处理后,鲜茧生丝丝胶稳定性较差,其抱合力下降幅度较大;鲜茧经过煮茧工艺,在一定程度上能够提高生丝的抱合稳定性;干茧生丝、鲜茧生丝及其浸泡后生丝的结晶度、取向度相差不大;干茧生丝、鲜茧生丝及其浸泡后生丝的断裂强度均超过3.5cN/dtex,能满足基本的织造要求。     

煮茧药物触蒸前处理对天蚕茧缫丝效果的影响

对天蚕茧进行煮茧药物触蒸前处理，结果发现解舒率、缫丝上车率，出丝率、练减率均得以提高，天蚕丝类节减少，外观更加艳绿。     

从家蚕茧中调制的丝素低分子化

家蚕茧经过干茧、煮茧、缫丝各加工过程形成生丝,经精练后作为纤维材料用于衣料。不过,近年来,丝素作为蛋白丝材料,已经用于非纤维领域。这种丝素通常以鲜茧、干茧、生丝为原料,精练后制取的。茧蛋白由丝素和丝胶组成,但目前考虑使用的只是通过精练,去除丝胶后的丝素。不过,在将丝素用作衣料材料时,虽然是没有问题,但要将它用作蛋白     

真空渗透在立缫上的应用

将真空渗透煮茧工艺用于立缫生产中，与温差渗透相比，茧层吸水充分，渗透完全、均匀、瘪、薄头汤茧减小，内层落绪率减少，生丝含胶量增多，但新茧有绪率及解舒率相对降低。     

基于氨基酸偶合显色的丝胶蛋白定量分析

为了解决在蚕丝精练实际生产中监测练减率的问题,利用丝胶蛋白中氨基酸残基与重氮盐偶合显色的特征反应来推算练减率。文章首先绘制了氨基酸模拟丝胶蛋白偶合显色的吸光度—氨基酸浓度标准工作曲线,并且研究了重氮盐的稳定性、偶合反应pH值对偶合吸光度的影响,以及丝胶蛋白碱水解后的沉淀物成分。结果表明,在0℃时重氮盐能稳定保存,但温度升高会导致其不稳定;偶合反应pH值控制在10左右时,偶合效率较高。由于精练残液碱水解后与重氮盐偶合显色推导的练减率较实际练减率低3%～4%,丝胶蛋白碱水解沉淀物不含丝胶成分,因此加上实验误差,能够反映实际生产中蚕丝精练的脱胶情况。     

桑蚕丝脱胶试验研究

采用0．05g／L碳酸钠溶液对桑蚕丝在煮沸的条件下精练0．5h,再用去离子水洗涤2次,除去盐离子及蚕丝表面的丝胶蛋白,得到脱胶蚕丝,烘干后计算生丝脱胶率,并用苦味酸胭脂红溶液及傅立叶红外光谱对其进行分析。研究结果表明,所选生丝含胶率约为32．18％,脱胶3次基本上可将丝胶除尽。     

生丝公定练减率研究

通过收集并测试我国生丝主产地大批量有代表性样品的练减率,分析了我国生丝练减率的分布规律;根据我国生丝的实际练减率和发展趋势,研究了生丝公定练减率,并在生丝公量与最终用户要求的丝素量之间建立起完全对应一致的关系.     

技术问答

问:怎样减少生丝切断? 答要减少生丝切断,一般应做好以下工作: 1.正确掌握煮茧和缫丝工艺操作。煮茧和缫丝的工艺操作过程,就是使茧子形成生丝。生丝的强度好否,制丝是起着决定性作用的。所以,在保证蚕茧解舒和提高洁净成绩的前提下,煮茧应尽可能减少丝胶溶失量;缫丝应做准定粒配茧,保持鞘丝一定的长度和捻数,合理除类和接结等,从而增加丝条的强力和抱合力。     

有无煮茧工序的自动缫丝成绩对比及讨论

首先就有煮茧与无煮茧工序的自动缫丝分别进行了试验,然后对2种工艺路线所得的实缫数据进行对比,经过分析和讨论认为,相对于有煮茧工序缫丝而言,无煮茧工序缫丝存在内外茧层丝胶膨润不均匀的概率较大,导致实缫效果不好,且影响生丝品质,即省略煮茧工序的相关技术尚不成熟,有待进一步研究。     

常规触蒸对茧包中、边部位茧的丝胶溶失率及其生丝机械性能的影响

通过对常规蒸茧包中间与靠边部位茧的茧层丝胶溶失率及其制得生丝的强伸力、黑板卷绕过程中丝条张力的测试,并对产生原因进行了探究,初步揭示了常规触蒸对茧包中间与靠连部位茧的丝胶溶失率及其生丝机械性能的影响,为进一步改善触蒸设备及工艺提供了依据。     

如何提高自动缫生丝断裂伸长率

结合重庆地区自Ｄ３０１Ａ自动缫丝机投产以来,生丝质量总体水平提高,但断裂伸长率却有所下降的现状,通过对影响生丝断裂伸长率的三大主要因素：生丝的含胶量、缫丝张力、生丝回潮率分别作了较为详尽的分析。提出：改善蚕品种;加强复摇现场湿度管理,保证丝片回潮率达到一定范围;改进缫丝工艺条件;规定并减小缫丝张力;适当使用复摇助剂,增加丝条柔软性等措施,生丝的断裂伸长得到有效提高。     

粗旦茧丝结构与性能

利用显微镜观察离子刻蚀后茧丝截面形态，并运用计算机图像处理技术测量其形态尺寸，测定丝素纤维结晶度及茧层丝胶溶失量，定量分析粗旦茧工艺性能以及由其缫制的生丝的机械性能，结果表明粗旦丝结构与性能间关系极为密切。     

针织用生丝的柔软处理工艺研究

生丝柔软工艺是其编织产的一道重要工序,对真丝针织产品的质量起了很大的作用,文章从初始模量,断裂伸长,润滑度变化等几个方面,分析了不同泡丝剂和不同处理工艺引起丝胶聚集状态改变对丝条柔软性能的影响,通过实验,得出了最佳工艺,并从理论上作了分析研究。     

Comparative analysis of the effect of ozone treatment on the properties of mulberry and tassar silk fabrics

The effect of ozone treatment on the properties of raw and degummed mulberry and tassar silk fabrics has recently been studied, and the investigation of results has been published. The variables, namely, wet pickup, pH and treatment time used in the treatment have shown a significant effect on properties such as the yellowness index, breaking strength, breaking elongation, amino group content, weight and flexural rigidity of the silk fabrics. In addition to this study, a comparative analysis has been made to find the difference in properties of ozone‐treated raw and degummed mulberry and tassar silk fabrics, for conditions that showed a significant effect on the properties, and these are presented in this paper. The results show that ozone treatment has a pronounced effect on the properties of mulberry raw and tassar raw silk fabrics compared with mulberry degummed and tassar degummed silk fabrics.     

乙醇处理茧层丝胶性能的变化

用氨基酸分析、热分析和红外光谱分析等方法对经乙醇处理后的茧层丝胶结构性能变化进行了探讨研究，为确定茧丝绸加工中重要工序（如烘茧、煮茧、生丝浸泡等）的最佳工艺条件，提供了基础理论依据。     

EFFECT OF A KAPPA CARRAGEENAN/LOCUST BEAN GUM MIXTURE ON BIND AND COOKING LOSS IN HIGH MANNURONATE ALGINATE RESTRUCTURED BEEF

Raw and cooked bind properties, cooking loss and pH were evaluated when adding three levels (0%, 0.25%, 0.50%) of a kappa carrageenan and locust bean gum mixture (C/LBG) to finely and coarsely ground high mannuronate alginate restructured beef. Treatments included variable levels of the following dry additives: Alginate (0.50%-1.00%), calcium carbonate (0.10%-0.20%) and glucono-delta-lactone (GDL, 0%-0.80%). Raw breaking strength of finely ground formulations was increased by elevated alginate levels (P<0.05), but was not affected by C/LBG addition (P>0.05). The effect of alginate and C/LBG on cooked bind properties depended on whether finely or coarsely ground meat was used. Sensory evaluations of coarsely ground treatments suggest that sufficient raw and cooked bind was achieved using 0.50% alginate, 0.10% calcium carbonate and 0.60% GDL. Addition of 0.50% C/LBG and/or 0.75% alginate to coarsely ground formulations further reduced cooking loss (P<0.05) by relatively 13% and 17%, respectively. No interaction between C/LBG and alginate was found (P>0.05).     

降低制丝厂原料成本的实践

对缫丝过程中茧在索绪锅、缫丝槽内停留时间与丝胶溶失率和缫折的关系；“索绪四定”与索绪效率、缫折的关系；理绪操作技术与理绪效率、缫折的关系进行了反复试验，从而找出在缫丝过程中降低原料成本的方法。     

RELATIONSHIPS AMONG CHEMICAL, COOKING AND COLOR PROPERTIES OF BEEF PATTIES COOKED TO FOUR INTERNAL TEMPERATURES

A study involving five laboratories and nationwide sampling of ground beef was undertaken to determine cooking and color properties of patties cooked to 52.7, 65.6, 71.1 and 79.4C. The design of the study included purchase location (local, distant) and patty handling prior to cooking Pesh, thawed either as patties or bulk ground beef). Purchase location was not a statistically significant influence on cooking and color properties. Patties processed from bulk thawed product had a higher amount of brown cooked color. A strong relationship existed between visual and instrumental measures of red color in cooked patties. However, correlations among other cooking properties were low. Patties with higher fat content were associated with shorter cooking times, lower cooking yields and more brown cooked color. The low relationships between raw and cooked patty properties limits the use of raw ground beef properties as predictors of food safety in cooked beef patties. This further supports the use of instant read meat thermometers in cooking beef patties to at least 71C.