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李姗姗  曹红梅  艾丽  徐明  朱亚伟 《丝绸》2022,(12):46-53
Synthetic fibers are widely used because of their stable chemical properties high mechanical strength and low cost. Among them polyester has the largest production and is the most widely used and China is also the country with the largest polyester production in the world. With the technological progress of energy saving and emission reduction of liquid disperse dyes the technology of micro printing of polyester and polyester / spandex fabrics has been realized. Based on the high market share of black polyester / spandex printed fabrics and the increasing market demand for functional finishing (e. g. anti-static finishing water repellent finishing UV resistance finishing etc.), it is of great significance to study the process of one-step short processing of polyester printing and functional finishing using carbon-based materials (e. g. carbon black). Carbon black is a gray-black organic pigment with good antistatic and anti-UV properties. It is an eco-friendly advanced material that integrates printing dyeing and functional finishing. To make up for the lack of color depth of carbon black pigment a disperse black dye and carbon black pigment in the same bath preparation scheme are chosen to prepare a functional liquid carbon black @ disperse black dye (CB-D). Not only does CB-D meet the requirements of deep black printing but also it can simultaneously provide water-repellent finishing to the fabric. In this way the application of organic fluorine or organic silicon resin can be dispensed with. A functional liquid CB-D was prepared by pre-dispersion and zirconium oxide grinding method under the action of abrasive agent AL50 (anionic / non-ionic surfactant complex) . The effects of CB-D mass fraction binder type binder D101 mass fraction baking temperature and time on color (L∗ value) rubbing and soaping colorfastness were investigated by optimizing the printing process of liquid CB-D. At the same time the fixation mechanism of CB-D was investigated and the properties of polyester-spandex printed fabrics were tested. The stability of CB-D and the colorfastness of polyester-spandex printed fabrics to hot-wash effluent were investigated by the rate of change of absorbance. The effect of hot-washing on dye floating in the printed area and dye staining in the non-printed area was characterized by the brightness of the printed area L∗ value and the whiteness of the non-printed area (CIE whiteness W10). The properties of CB-D were characterized by scanning electron microscopy and transmission electron microscopy and the antistatic property water repellency air permeability moisture permeability and tensile breaking strength of the fabrics were tested. (i) The first functional liquid CB-D with excellent stability is prepared by grinding carbon black and disperse black dye composed of orange 288 purple 93 and blue 291:3 in the same bath. (ii) A durable fluorine-free and silicone-free water repellent black polyester spandex fabric is prepared reducing the cost of functional finishing and environmental pollution. The preparation of durable water-repellent polyester spandex fabrics without a functional finishing agent is a new technology. CB-D as functional organic melanin with excellent performance and simple processing is a new low-carbon and eco-friendly material and ecological printing and dyeing process. (i) As for the black polyester spandex fabric prepared by a micro-printing process the color fastness of deep black color is not less than grade 4 the white ground is not stained and the color of wastewater is very low. The printing process requires 5% functional CB-D and 8. 5% binder D101. (ii) The black polyester spandex fabric has excellent and durable water repellency air permeability moisture permeability and antistatic property. The water contact angle is 132° anti-static grade is A and the air permeability and moisture permeability are more than 260 mm / s and 2 880 g / (m2h) respectively. After 30 times of home washing it almost keeps the original excellent performance. (iii) The CB-D prepared based on carbon black and disperse black dye is a colloidal aggregate that easily forms continuous carbon black aggregates on the fiber surface showing more excellent porosity film formation and water repellency while maintaining air permeability and moisture permeability. Carbon black is a low-cost material and the liquid CB-D prepared by modifying carbon black with disperse black dye has a new use in preparing functional textiles with good application prospects. © 2022 Authors. All rights reserved.  相似文献   
203.
正元宝山发电责任有限公司3号机组为600MW机组,引风机有高、低速2种运行方式(高速740r/min,低速590r/min),通过改变引风机静叶开度来调整炉膛压力。由于这种调节方法仅仅是改变通道的流通阻力,而驱动源的输出功率并没有改变,节流损失相当大,浪费了大量电能。为此,采用变频调节方式对引风机控制系统进行改造,以提高机组运行的经济性。因逻辑设计问题,在引风机进行高、低速切换时存在隐患,影响机组安全稳定运行,因此还需对控制逻辑进行修改。  相似文献   
204.
局部均值分解(Local mean decomposition,LMD)在分析非线性、非平稳信号时表现出特有的分析能力,能够有效获得非平稳信号的时频特征,但是局部均值分解过程中的端点效应会导致分解结果失真,针对这一问题,从振动信号解调分析角度出发,提出基于对称差分能量算子解调的局部均值分解端点效应抑制方法,采用局部均值分解方法将原信号分解为一系列单分量信号,然后对每一个单分量信号进行三点对称差分能量算子解调,得到各单分量信号的瞬时幅值和瞬时频率,从而获得原信号的时频分布。为评价该端点效应抑制方法的抑制效果,定义一种评价标准,通过与其他两种端点效应抑制方法进行比较,验证该方法的优越性。仿真和试验结果表明该方法能够有效抑制LMD端点效应,实现旋转机械故障的有效诊断。  相似文献   
205.
微通道内交流电渗微泵的流速与电极表面双电层的结构与电荷分布密切相关,根据传统双电层理论和交流电渗速度公式可以预测交流电渗流速分布和速度峰值处的转折频率.试验发现,由此得出的交流电渗流速峰值比试验值大数倍.考虑紧密层和中间层厚度对交流电渗流的影响,提出三电层模型,给出三电层等效厚度和等效相对介电常数的求解方法,对传统的交...  相似文献   
206.
目的:对2010~2012年哈尔滨市生活饮用水水质进行卫生监测分析。方法:选取磨盘山净水厂、哈尔滨市各制水公司等制水公司做为出厂水监测点,进行水质监测。结论:大多数水厂的样品合格,但黑河市生活饮用水的水质不容乐观。  相似文献   
207.
螺杆钻具是以钻井液压为动力的一种井下动力钻具,通过容积式马达,向钻头提供转速和扭矩。研究了螺杆钻具的工作原理,确定了螺杆钻具的主要性能参数,开发了螺杆钻具正向检测系统。利用该系统输入多种工况下的动力液排量、钻具两端压力、输出转速和扭矩等参数,测试并处理采集的相关数据,从而得到螺杆钻具的性能参数。并通过测试实例说明了螺杆钻具正向检测系统的可行性。  相似文献   
208.
分析了国家重点档案管理中应用文献影像技术的必要性,提出了技术方案。以“数字敦煌”为例具体分析了文献影像技术的应用。  相似文献   
209.
AgentX在网络管理数据采集中的应用   总被引:1,自引:0,他引:1  
介绍了可扩展代理(AgentX)的协议机制,提出了一种AgentX代理在网络管理数据采集中的应用方案,使代理具有灵活、动态的可扩展性,同时也提高了数据采集的可靠性.  相似文献   
210.
2006年4月2日。阿尔卡特与朗讯达成合并协议,正当业界以为一个电信航母呼之欲出的时候。美监管部门的发难以及朗讯本身存在的问题却让这一基本定局的合并,遭遇到冰点。  相似文献   
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