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31.
以壳聚糖(CTS)和活性艳蓝KN-R染料为原材料,通过两步反应法制备新型N,O-羧甲基壳聚糖染料,用红外光谱(FTIR)、X射线衍射(XRD)、元素分析仪分析其结构和化学基团,并用紫外可见分光光度计对其水溶性进行检测;采用常压浸渍法制备N,O-羧甲基壳聚糖染料染色薄木,用光谱光度仪进行表面颜色及日晒和水洗色差测量;用菌落计数法定量表征其抗菌性能。结果表明:CTS分子中大量—OH、少量—NH2基团被—CH2COOH基团取代,染料中的—SO-3和N,O-羧甲基壳聚糖中质子化的—NH+3发生反应;羧甲基化和染料接枝反应使得CTS结晶度下降;N,O-羧甲基壳聚糖染料的水溶性得到显著改善;N,O-羧甲基壳聚糖染料可明显改善薄木的染色效果,且染色薄木的耐日晒和耐水洗牢度均提高;N,O-羧甲基壳聚糖染料染色薄木的抗菌性能优于活性艳蓝KN-R染色薄木。 相似文献
32.
解淀粉芽孢杆菌LC03的芽孢漆酶具有较好的稳定性,通过制备具有漆酶活性的芽孢悬液,研究了芽孢漆酶对4种合成染料RB亮蓝、活性黑、靛红和结晶紫的脱色效果,并筛选出促进染料脱色的漆酶介体,同时考察了酶浓度、介体浓度对模拟染料废水脱色的影响。结果表明:RB亮蓝﹑活性黑和靛红在无介体时不能被脱色,在乙酰丁香酮(ACE)介导下的脱色率都超过了60.00%;在pH9.0时,芽孢漆酶-介体系统对模拟染料废水脱色的酶浓度和介体浓度分别为88.64 U/L和0.5 mmol/L时,2 h后脱色率可超过80.00%,表明该芽孢漆酶在染料废水的处理上具有较好的应用前景。 相似文献
33.
Jae?Whan?ChoEmail author Sun?Hwa?Lee Jung?Hyun?So Jae?Yun?Jaung Kee?Jong?Yoon 《Fibers and Polymers》2004,5(3):239-244
Solution-cast films of polymethylmethacrylate (PMMA) and polyurethane (PU) containing polymeric styryl dye up to 5% by weight
were prepared to investigate their acid-sensitivity and mechanical and thermal properties. Original red samples due to styryl
dye turned out yellow very rapidly as they were exposed to acid vapor of hydrochloric acid or p-toluenesulfonic acid. According
to UV/VIS spectroscopic measurements, characteristic peak intensities near 430 nm and 520 nm increased or decreased relatively
with exposed amounts of acid, respectively. Both PMMA and PU samples showed uniform color distribution due to a good miscibility
between polymer and dye which can be evidenced by measurements of glass transition temperature. No significant difference
in acid-sensitivity was found between PU and PMMA except relative absorbance. However, dependence of their mechanical properties
on dye content was somewhat different with PU or PMMA. In case of PMMA, modulus and breaking stress increased up to about
50% with increasing dye content, whereas those of PU samples showed only slight increase. It was ascribed to whether the matrix
polymer was in the glassy or rubbery state. 相似文献
34.
35.
关于紫胶原胶的含铜情况过去尚末见报道,应用原子吸收分光光度法测出紫胶原胶的铜含量为9.49ppm。将紫胶原胶分成粗粒胶、细粒胶、粉胶和紫胶虫尸体四个级分,分别测出其铜含量为8.06ppn、13.44ppm、16.38ppm、49.66ppm。 紫胶原胶中的铜高度富集于紫胶虫尸体之中,它是引起紫胶红色素铜污染的主要污染源。从紫胶的生物来源和紫胶红色素的化学本质分析,紫胶原胶中紫胶红色素的铜污染是不可避免的。 相似文献
36.
The dye-resist effect and leveling properties of hetero-mulifunctional dye-resist agents in acid dyeing of wool were investigated.
The dye-resist agent with dichlorotriazinyl group achieved better resist effectiveness than those with monochlorotriazinyl
group. The resist effectiveness was improved by increasing the number of sulfonate group in dye-resist agents. Also, the resist
agents with more sulfonate groups showed better dye-assist effectivness, attributable to the increased electrostatic attraction
between dye-resist agents and the cationic dye. However, the leveling properties of dye-resist agents decreased with the number
of sulfonate groups in the molecule. 相似文献
37.
Six nano disperse dyes were prepared using corresponding O/W nanoemulsions which were obtained with sodium laurylsulphate
and caprylic triglyceride. The average particle size of the dyes prepared were in the range of 110–130 nm. Exhaust dyeing
using nano dyes resulted in low exhaustion yields of 17–26 % on regular polyester fiber and 28–38 % on ultramicrofiber polyester.
The observed low exhaustion yields of nano disperse dye can be explained by the solubilization of dye particles into surfactant
micelles as well as the high stability of the nanoemulsions, these might reduce the capacity of dye uptake onto the fibers.
However, higher K/S values of dyeings with nano dyes on ultramicrofiber sites compared to those on regular polyester sites
suggested their potential to be more efficient dyes for finer denier microfiber polyesters. 相似文献
38.
Five yellow disperse dyes were synthesized and their dyeing, fastness and photodegradation behaviors were investigated. It
was found that dyes derived from phenylindole and N-alkylaminobenzene showed dye uptake directly proportional to the dye concentration,
but the build-up of dyes derived from carbazole and pyridone were not good. The wavelength at maximum absorption, molar extinction
coefficient, and the tendency to the photodegradation were strongly dependent on the electron donating ability of the coupling
component. The dye, whose coupling component was phenylindole, possessed the excellent dyeing properties and the high degree
of lightfastness. UVA had an effect on the inhibition of the photodegradation especially for the easily photodegradable dyes. 相似文献
39.
[目的]研究食用菌苎麻骨培养物对活性艳红X-3B染料的脱色效果。[方法]将香菇、平菇和金针菇3种常见食用菌株接种至苎麻骨培养基上培养,研究培养物对50 mg/L活性艳红X-3B溶液的降解脱色效果。[结果]香菇培养物处理3 h对染料溶液脱色率可达92.17%,平菇培养物处理3 h对其脱色率可达72.40%。此外,香菇培养物对该染料溶液具有很好的重复处理效果,但重复处理次数越多脱色效果越差。[结论]香菇和平菇的苎麻骨培养基培养物对活性艳红X-3B溶液具有较好的脱色效果。 相似文献
40.
Previously, we have reported a method for producing photochromic wool fabric by applying a thin layer of hybrid silica-photochromic
dye onto the wool surface. While the photochromic coating showed a very fast optical response and had little influence on
the fabric handle, its durability was poor. In this study, the durability of the photochromic coating layer was improved by
introducing epoxy groups into the silica matrix via co-hydrolysis and co-condensation of an alkyl trialkoxysilane compound
(ATAS) and 3-glycidoxypropyltrimethoxysilane (GPTMS). The presence of epoxy groups in the silica enhanced both washing and
abrasion durability or fastness. In addition, the optical response speed was slightly increased as well. Effects of the type
of alkyl silane and the GPTMS/alkyl silane ratio on the coating durability, fabric handle and optical response were examined. 相似文献