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41.
本文利用系统工程原理和回归正交实验方法,在小型去草梳毛机上模拟真实加工条件,对除草装置的主要工艺参数:除草刀与莫雷尔辊(或开毛辊)之间隔距,除草刀表面线速度.除草刀罩壳前、后开口高度进行了优化。得出,①除草刀与开毛辊或莫雷尔辊之间的隔距越小,除草率和落毛率越高。②除草刀罩壳的前开口高度越大,落毛率越高。但当取小隔距时,前开口高度越大,除草率越高。③除草率与线速度比V_1/V_2成正比(指除草刀与开毛辊或莫雷尔辊之间线速度比);而落毛率则与其为负指数关系。当线速度比大于6时除草率较高同时落毛率较小.④加大除草刀罩壳的后开口高度,可提高除草率并减少落毛率。实验结果与作者提出的除草刀作用数学模型分析一致。此外,还优选出上述几个除草作用区的工艺参数调节范围。使除草效率分别提高32~52%.  相似文献   
42.
《先进技术聚合物》2018,29(4):1255-1260
Acoustic felts are commonly used in white goods. Bearing that into mind, this paper aims to enhance sound absorption behavior of such felts, in particular, within the low and medium frequency ranges. In doing so, wool and jute felt samples were coated with electrospun polyacrylonitrile nanofibrous membrane. These nanocoated felts were studied in terms of their sound absorption performance, air permeability, and surface morphology. The results indicated that the air permeability of the felts could be drastically decreased by coating with nanofibers, which was required for better acoustic performance of felt‐like structures. Moreover, the samples having higher amount polyacrylonitrile nanofibers tended to demonstrate better sound absorbency.  相似文献   
43.
Adsorption of water vapour on wool provides not only textile comfort, but also convenience in transportation due to increase in its bulk density. The adsorption and desorption isotherms of water vapour for wool were determined by both volumetric technique using a Coulter Omnisorp 100CX instrument and gravimetric method employing a Cahn 2000 electronic microbalance. Adsorption isotherm fitting to B.E.T. model and hysteresis on desorption was observed. The average effective diffusion coefficient of water in wool was found to be 8.4 × 10-14 m2s-1 at 25°C from gravimetric data. The effects of packing height and air velocity on the breakthrough curves were also investigated in the wool packed columns. For pseudo first order model, k values changing between 0.33 × 10-6 – 69 × 10-6 s-1 was obtained for 2.2–6.4 cm s-1 air velocity and 0.05–0.20 m packing height ranges.  相似文献   
44.
主要介绍了图像处理技术测定丝/毛混纺比时多种特征参数的选择及识别敏感度的分析,并利用多元分析方法对目标信号进行了识别和分类。  相似文献   
45.
It is well known that top dyeing is an Important step in wool processing, but it will result in the damage of fibre in normal dyeing. How to measure the damage quickly and to evaluate it quantitatively are vital important for wool industry and also interested for wool researchers. For the purpose, nineteen tops dyed in normal condition from three wool textile mills in China were tested with TENSOR, a bundle fibre tensile tester. The experimental results showed that the dyeing damage rate of bundle strength of these tops is 6% - 7% in average and some tops were higher than 10% dyeing damage. Meanwhile, the dyeing damages for different wool mills were discussed . It is obvious that bundle tensile test is an efficient and quick method to evaluate the damage caused by top dyeing and to identify the difference between wool mills in quality and quantity.  相似文献   
46.
建立了同时测定含脂羊毛中20种有机氯和有机磷类杀虫剂残留的气相色谱-柱后分流-反吹检测方法.通过二氧化碳超临界萃取技术提取含脂羊毛样品中的杀虫剂残留并经中性氧化铝固相萃取柱净化,采用气相色谱-柱后分流技术,可以同时得到3个检测器信号(MSD、μECD和NPD),可对两类杀虫剂准确定性和定量分析.同时运用反吹技术,减少样品中高沸点杂质对色谱系统的污染.3个添加水平的回收率为85.6%~120.9%,相对标准偏差在1.2%~17.3%之间.方法干扰小、重现性好、自动化程度高,能够对含脂羊毛中有机氯和有机磷类杀虫剂残留准确地定性定量分析.  相似文献   
47.
Red-G dye is one of the main dyes used in the textile industry to dye alpaca wool. Therefore, considering the large volume of processed wool in Perú, the development of efficient technologies for its removal is a present scientific issue. In this study, an integrated system based on hydrodynamic cavitation (HC) and photo-Fenton process was evaluated to remove the Red-G dye. Using a hybrid cavitation device (venturi + orifice plate), the effect of pH was evaluated, achieving 21 % of removal at pH 2 which was more than 80 % higher compared to pH 4 and 6. The effect of temperature was also evaluated in HC-system at pH 2, where percentage of dye degradation increased at lower temperatures (around 20 °C). Then, 50.7 % of dye was removed under optimized condition of HC-assisted Fenton process (FeSO4:H2O2 of 1:30), that value was improved strongly by UV-light incorporation in the HC-system, increasing to 99 % removal efficiency with respect to HC-assisted Fenton process and reducing the time to 15 min. Finally, the developed cavitation device in combination with photo-Fenton process removed efficiently the dye and thus could be considered an interesting option for application to real wastewater.  相似文献   
48.
采用双氧水预处理并结合蛋白酶—脂肪酶工艺细化羊毛纤维。通过正交试验分别确定了羊毛双氧水预处理的条件和蛋白酶—脂肪酶处理工艺条件,并进行了生物酶细化处理羊毛的对比试验。结果表明采用双氧水预处理并蛋白酶-脂肪酶细化处理羊毛后,羊毛纤维鳞片层受到一定程度的破坏,纤维的直径降低约2.3μm,断裂强力保持率达到94.8%。  相似文献   
49.
研究了羊毛在甲酸中的溶胀行为和剪切力及超声波空化作用下的破碎过程.结果表明,甲酸是实现羊毛溶胀的有效溶胀试剂,羊毛在98%甲酸溶液中的径向溶胀率达到80%,溶胀后的羊毛在机械力的作用下能够分解为直径3~5μm、长度100μm左右的皮质细胞,以及直径0.3~0.51μm、长度30~40μm的巨原纤.  相似文献   
50.
为了改善以及较好地研究聚乙烯醇纤维的染色性能,制备了不同粉体含量的PVA/超细羊毛粉体共混膜,同时探讨了PVA/超细羊毛粉体共混溶液的可纺性能.超细羊毛粉体的平均粒径为2.01μm.SEM扫描电镜显示,超细羊毛粉体与PVA之间有较好的相容性.随着共混膜中超细羊毛粉体含量的增加,共混膜的上染率,红度(a*)值以及K/S值都逐渐的增加.当超细羊毛粉体含量为33.3%时,PVA/超细羊毛粉体共混膜的染色性能几乎同超细羊毛粉体的染色性能一样;当超细羊毛粉体的含量超过33.3%时,PVA/超细羊毛粉体共混膜的染色性能会大幅度增加,甚至这些共混膜的K/S值会超过超细羊毛粉体的K/S值.  相似文献   
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