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991.
为解决染料难以对超高分子质量聚乙烯(UHMWPE)纤维上染的问题,筛选具有超高疏水、良好结构平面性的甲基黄分散染料对UHMWPE纤维进行染色,并探讨其染色性能。讨论了染色温度、时间、分散剂(AEO-9)用量及p H值等因素的影响,测定了甲基黄染料对UHMWPE纤维的染色动力学与热力学行为。结果表明,甲基黄染料对UHMWPE纤维具有良好的染色性能,其优化工艺为:染色温度130℃,分散剂用量0.3%,时间60 min,p H值5,此时染色所得纤维各项色牢度均达到3~4级以上;通过拟合计算甲基黄染料对UHMWPE纤维吸附等温线类型为Nernst型吸附,半染时间为24.34 min,130℃时的扩散系数为5.21×10-17m2/s,标准亲和力约为5.56 k J/mol。  相似文献   
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994.
Abstract

Dyeing is supercritical CO2 is one of the most advanced dyeing technologies. The dyeing medium is not water but carbon dioxide in the supercritical state (temperatures above 31°C and pressures above 74 bar).

The effect of pressure and temperature on dyeing of PET in supercritical CO2 with only one dye and with mixtures of two or three dyes has been investigated.

The variations of pressure (250 in 300 bar) and temperature (70 in 130°C) cause differences in colour, especially when mixtures of dyes are used. The dyed samples were evaluated using colorimetry and the extraction of dyes from the fabric.

The amount of all dyes on the fabric rises with the rising temperature due to the accelerated motion of molecular chains and the formation of the free volume in the fibre, so important for the diffusion of dyes. The change of pressure does not after the amount of fixed dyes significantly, but the ratio between the dyes is changed when dyeing with mixtures of dyes.  相似文献   
995.
《分离科学与技术》2012,47(11):1684-1688
Absorption spectroscopic studies of Congo red (CR) in interaction with FeCl3 in aqueous medium have been reported in this article. The interaction of CR with FeCl3 has been investigated with an aim to explore a possible low cost and efficient way to remove CR from industrial waste water. The removal mechanism is based on the formation of a complex of iron with anionic part of the CR molecule in interaction with FeCl3. An exceptionally high removal rate of 2670 mg/g has been observed at 100 mg/L initial CR concentration and enhanced removal rate was found with increasing initial CR concentration.  相似文献   
996.
研究了高铁酸盐溶液对活性黑KBR的降解效果,并采用UV-Vis、FTIR对降解机理进行分析。结果表明,高铁酸盐溶液对KBR脱色效果较好,脱色速率较快,最佳pH范围≤8。Fe(Ⅵ)最佳投加量为25 mg/L,反应60 min时,对KBR的色度和COD去除率分别为80.3%、62.5%。在氧化降解过程中,Fe(Ⅵ)和ClO-表现出协同作用。UV-Vis和FTIR分析表明,降解过程中染料分子的偶氮键被破坏,苯环和杂环被打开,染料大分子被氧化为小分子中间产物。  相似文献   
997.
本文采用有限元法,对某移门式卷染机的矩形开孔部位进行了应力计算和强度分析,对矩形孔边应力分布和开孔补强设计进行了讨论。  相似文献   
998.
Throughout the past ten years, comprehensive understanding of fundamental and applied research has focused on functional coating and specifically on microencapsulaion. In this study, weak polycation poly(allylamine hydrochloride) and strong polyanion poly(sodium styrene sulfonate) were used for fabrication of nano film through layer by layer technique on the surface of disperse dye particles. Then micron‐sized particles were surrounded by poly(urea formaldehyde) using in‐situ polymerization. Chemical structure, surface morphology, and size distribution of these novel microcapsules were characterized by Fourier transform infrared spectrometry, differential scanning calorimetry, optical microscopy, and scanning electronic microscopy. Size and surface morphology of the microcapsules can be optimized by selecting proper weight ratio of urea to formaldehyde and core to shell material type, and amount of surfactant and agitation rate. This technology demonstrated good capability in several applications in textile industry, such as dying fabrics because of saving huge amount of water and showing slow‐release property of dye without using dye assistant agents. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
999.
The electrochemical oxidation of acid black 210 dye (AB-210) on the boron-doped diamond (BDD) was investigated under different pH conditions. The best performance for the AB-210 oxidation occurred in alkaline phosphate solution. This is probably due to oxidizing agents such as phosphate radicals and peroxodiphosphate ions, which can be electrochemically produced with good yields on the BDD anode, mainly in alkaline solution. Under this condition, the COD (chemical oxygen demand) removal was higher than that obtained from the model proposed by Comninellis. Electrolyses performed in phosphate buffer and in the presence of chloride ions resulted in faster COD and color removals in acid and neutral solutions, but in alkaline phosphate solution, a better performance in terms of TOC removal was obtained in the absence of chloride. Moreover, organochloride compounds were detected in all electrolyses performed in the presence of chloride. The AB-210 electrooxidation on BDD using phosphate as supporting electrolyte proved to be interesting since oxidizing species generated from phosphate ions were able to completely degrade the dye without producing organochloride compounds.  相似文献   
1000.
In this study, a procedure for preparation of organic–inorganic composite was established. The procedure was based on gamma irradiation polymerization of polyacrylamide (PAAm) in presence of maleic acid (MA), clay minerals [kaolinite (K)], or [montmorillonite (M)] and methylenebisacrylamide (NMBA) as a crosslinker. The functionality of the produced adsorbents were assayed using FTIR spectroscopy, SEM, and XRD and were evaluated for sorption of neutral red (NR) dye from aqueous solutions via batch sorption experiments. Various factors influencing the sorption behavior (e.g., pH, sorbent dose, and dye concentration) were studied. The sorption data fitted well with Langmuir isotherm model. Batch kinetic experiments showed that the adsorption followed pseudosecond‐order kinetic model with correlation coefficients greater than 0.999. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
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