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1.
Generation of hydroxyl radicals in the presence of buffered terephthalate solution produces flourescent 2-hydroxyterephthalate. Wool, nylon, cotton and polyester all generate hydroxyl radicals when irradiated with UVA light, and to a lesser extent with blue light, in terephthalate solution. Trace metal ions (particularly iron and copper) contribute to hydroxyl radical generation in wool and cotton. UVA irradation of wool in deuterated solution does not affect the concentration of hydroxyl radicals or the amount of yellowing observed relative to undeuterated solution. This suggests that 1O2 is not involved in the wet photoyellowing of wool. Although the photoinitiation stages are clearly different, it is likely that similar free radical processes are responsible for both hydroxyl radical production and wet photoyellowing in all four fibre types. This straight forward fluorescence technique has potential to correlate the free radical photodegeneration of fibres in the presence of various additives designed to improve performance.  相似文献   

2.
Fabric defect detection plays an important role in the textile production process, but there are still some challenges in detecting defects rapidly and accurately. In this paper, we propose a powerful detection method for automatic fabric defect detection using a deep convolutional neural network (CNN). It consists of three main steps. First, the fabric image is decomposed into local patches and each local patch is labelled. Then the labelled patches are transmitted to the pretrained deep CNN for transfer learning. Finally, defects are detected during the inspection phase by sliding over the whole image using the trained model, and the category and position of each defect is obtained. The proposed method is validated on two public and one self‐made fabric database. The experimental results demonstrate that our method significantly outperforms selected state‐of‐the art methods in terms of both quality and robustness.  相似文献   

3.
The thermal stability and radiation resistance of three polymers Nylon 6, acrylonitrile copolymer and polyester were investigated. The polymer samples were irradiated by low rate fission neutrons from a 252Cf source. The polyester showed a higher heat and radiation resistance than the two other polymers. It has to be recommended herein that polyester is the most suitable fiber for the manufacture of products in which heat buildup is produced during application, or products where radiation and heat resistance are required.  相似文献   

4.
In a previous article, we reported on the ozone‐gas treatment of wool and silk fabrics in relation to the gas‐phase processing of textile fabrics. The treatment incorporated an oxygen element into the fiber surface and contributed to an increase in water penetration into the fabric. In this study, nylon 6 and polyester fabrics were treated with ozone gas in the same way as that of the wool and silk fabrics. The treatment incorporated much more oxygen into the fiber surface in the form of ? COH and ? COOH, as shown by electron spectroscopy for chemical analysis. Water penetration increased considerably with treatment, and the apparent dyeing rate and equilibrium dye uptake were also improved, especially for the polyester fabric, despite an increase in the crystallinity. Therefore, it seemed that the treatment brought about a change not only in the fiber surface but also in the internal structure of the fibers (the crystalline and amorphous regions) with regard to the dyeing behavior. Further, the mechanical characteristics of the ozone‐gas‐treated polyester and nylon 6 fabrics were measured with a Kawabata evaluation system apparatus. The shearing modulus and hysteresis widths increased with treatment, especially for the polyester fabric. Therefore, it was clear that the treatment caused a change in the fabric hand to crisp. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1344–1348, 2006  相似文献   

5.
An alkaline dyeing of polyester with an alkali‐stable disperse dye, Dianix® Scarlet AD‐RG, was developed using sodium edetate as an alkaline buffering agent. The results obtained indicate the suitability of using sodium edetate for alkaline dyeing of polyester when compared with the control alkaline dyeing using Dianix AD system. Selected mono and bifunctional reactive dyes were used in combination with the alkali‐stable disperse dye for dyeing of polyester/cotton blend. Different dyeing methods for cotton and polyester/cotton blend fabrics using sodium edetate were evaluated in comparison with their respective control alkaline dyeing methods. The results of using sodium edetate in one‐bath two‐stage and two‐bath dyeing of polyester/cotton blend were comparable with that of the control dyeing method. Particularly, no change in the leveling and fastness properties was evaluated for all samples irrespective of the dyeing method. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

6.
The paper describes the mass coloration of polyester and nylon 6 using perylene-based pigments having groups structurally similar to the substrate. For this purpose, five perylene-based pigments were prepared by reacting 3,4,9,10-perylene tetracarboxylic acid dianhydride (PTDA) with methylamine, ethanolamine, glycine, 4-aminobutanoic acid and 6-aminocaproic acid. Structural characterisation of these pigments was carried out by elemental analysis, and electronic, i.r. and mass spectroscopy. The pigments were found to be stable up to 360d? C and started decomposing above this temperature. Mass-coloured polyester and nylon 6 fibres showed better pigment dispersion, darker shades and better fastness properties when compared with fibres produced by the chip coating method.  相似文献   

7.
尚伟 《中国橡胶》2006,22(6):6-8
目前国内生产锦纶帘布的企业有30余家,帘子布产能约32万~35万吨,其中采用引进技术设备的中国神马集团实业股份有限公司、陕西九棉实业有限责任公司、青岛联创实业有限公司、岳阳巴陵公司鹰山石油化工厂4家企业的年产能为9万吨。另外,据初步了解,浙江、江苏、山东等27家企业新建和扩大年产能约8万吨,预计2005年底锦纶帘布生产将形成年产40万吨的生产能力。笔者在中国橡胶工业协会骨架材料专业委员会2003年帘子布企业生产发展情况统计的基础上,经过对江苏、浙江、上海、山东地区帘子布企业和相关织布机企业及浸胶机企业的调查了解,现对近年全…  相似文献   

8.
Polyester fabric was hydrolysed using aqueous sodium hydroxide under microwave irradiation. Increasing levels of weight loss and thickness reduction were observed with increasing microwave intensity and increasing concentrations of sodium hydroxide. Comparison of the results obtained from the microwave irradiation method and the conventional heating method showed that the rate of hydrolysis was greater using microwave irradiation. The treated fabric was then dyed using microwave irradiation to heat the dyebath. Increased levels of dye uptake were observed with increasing weight loss of the hydrolysed polyester fabric.  相似文献   

9.
The use of polyester fabrics in a project to investigate the application of real wax batik print styles necessitated the application of a low-temperature dyeing technique. Consequently an ultrasonic dyeing method was explored, in which the use of appropriate pre-swelling of the substrate had been reported to give acceptable shade depths at 50d?C. Experiments involving three separate disperse dyes demonstrated little advantage for ultrasonic dyeing over conventional methods, particularly when carrier was incorporated into the dyebath. The depths of shade obtained were considerably inferior to those achievable in commercial dyeing at the boil with carrier included.  相似文献   

10.
To be more biocompatible, poly(N-isopropyl acrylamide) (PNIPAM) hydrogel, as a typical temperature-sensitive hydrogel, is expected to be linked with other materials of excellent biocompatibility. For this propose, poly(N-isopropyl acrylamide)-block-poly(3-O-allyl-α-D-glucose) (PNIPAM-b-POAG), a new diblock copolymer, was successfully synthesized from N-isopropyl acrylamide (NIPAM) and 3-O-allyl-1,2:5,6-di-O-isopropynylene-α-D-glucose (OAIG) via reversible addition-fragmentation chain transfer (RAFT) polymerization in the presence of cumyl dithiobenzoate (CDB). PNIPAM-b-POAG was characterized byFourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, and gel permeation chromatography (GPC). The critical micelle concentration (CMC) of the copolymer was 0.045 mg/ml measured by fluorescence spectroscopy. The copolymer solution exhibited a reversible sol-gel phase transitions with the increase or decrease of temperature. An in situ gel formed rapidly after subcutaneously injecting the copolymer solution into a Sprague Dawley (SD) rat, which indicated the copolymer has a good injectable property. The in vitro release result showed that methylene blue (MB) as a model was sustainably released by the temperature-sensitive PNIPAM-b-POAG diblock copolymer at 37 °C within 120 h. The copolymer showed no apparent cytotoxicity on L929 cells by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The novel temperature-sensitive hydrogel is a promising candidate for drug delivery.  相似文献   

11.
Various nickel arylsulphonates were synthesised and their protecting effects on the photofading of CI Basic Violet 3, CI Acid Red 94, CI Acid Red 87 and CI Acid Blue 74 examined on nylon fabric. The rates of photofading of the dyes were remarkably suppressed in the presence of nickel salts, while the addition of ultraviolet absorbers and conventional stabilisers afforded little retardation of the rate of fading. The antimicrobial activity against two species bacteria of nickel salts was also examined. This aftertreatment technique was shown to be safe for the environment and human health.  相似文献   

12.
Carbonation on concrete structures in underground sites or metropolitan cities is one of the major causes of steel corrosion in RC (Reinforced Concrete) structures. For quantitative evaluation of carbonation, physico-chemo modeling for reaction with dissolved CO2 and hydrates is necessary. Amount of hydrates and CO2 diffusion coefficient play an important role in evaluation of carbonation behavior, however, it is difficult to obtain a various CO2 diffusion coefficient from experiments due to limited time and cost.In this paper, a numerical technique for carbonation behavior using neural network algorithm and carbonation modeling is developed. To obtain the comparable data set of CO2 diffusion coefficient, experimental results which were performed previously are analyzed. Mix design components such as cement content, water to cement ratio, and volume of aggregate including exposure condition of relative humidity are selected as neurons. Training of learning for neural network is carried out using back propagation algorithm. The diffusion coefficient of CO2 from neural network are in good agreement with experimental data considering various conditions such as water to cement ratios (w/c: 0.42, 0.50, and 0.58) and relative humidities (R.H.: 10%, 45%, 75%, and 90%). Furthermore, mercury intrusion porosimetry (MIP) test is also performed to evaluate the change in porosity under carbonation. Finally, the numerical technique which is based on behavior in early-aged concrete such as hydration and pore structure is developed considering CO2 diffusion coefficient from neural network and changing effect on porosity under carbonation.  相似文献   

13.
This study discusses ink‐jet printing of nylon fabric with reactive dyestuff. Specifically, this paper investigates the impact of the concentration levels of pretreatment paste on fabric permeability, and examines the influence of various acid agents, hygroscopic agents and different processing conditions on colour yield. Results show that ink‐jet printing displayed excellent wet fastness in repeated wash testing. This study used four reactive dyestuffs, cyan, magenta, yellow and black, all of which achieved both wash fastness and crock fastness of grade 4.  相似文献   

14.
An experimental investigation was carried out to study the effect of a silicone coating on the mechanical properties of polyester/woven glass fabric composites, fabricated by resin transfer molding. E‐glass woven fabrics were coated with a silicone elastomer by solution dip coating. The effect of variation of silicone amounts on the impact resistance, toughness, and mechanical properties of the composite was determined. Short beam shear tests were performed to assess the effect of coating on the adhesion of the fiber to the matrix. The coated specimens exhibited worse interlaminar shear strength over that of uncoated fabrics. Three‐point bending tests were also performed to investigate the effect of the coating on flexural properties. Whereas flexural strength and Young's modulus decreased with increasing amount of coating, the toughness, represented by the area under the stress–strain curve, presented a maximum. Finally, notched Izod impact tests were carried out and the curve for the energy absorbed during impact versus the amount of coating also appeared to have a maximum, indicating an interesting slot for optimum impact performance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1300–1308, 2004  相似文献   

15.
With regard to the fact that currently there is no comprehensive method to predict diameter of polyurethane/solvent fiber from electrospinning, in this study, diameter prediction of polyurethane/solvent fiber was conducted using neural networks and an error of 166 nm was observed. This error shows that artificial neural networks (ANNs) can predict diameter of electrospinning polyurethane fibers well. Then, considering weak repeatability nature of electrospinning in fabricating fibers with desired diameter, least mean square is used to improve stability of neural network model that shows an error of 113 nm, which represented better results compared to common ANN. To investigate the effect of each one of parameters affecting fiber diameter, sensitivity analysis was conducted. Along with this predicting model, sensitivity analysis can be used to reduce parameters space before conducting future studies. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45116.  相似文献   

16.
The fatigue resistance of individual synthetic fibers can govern the performance of complex fiber assemblies such as tire cord and marine rope under certain loading conditions. This paper explores the relative performance of polyester and nylon 6,6 fibers and yarns, both dry and in aqueous solutions, primarily synthetic seawater. Fiber failure over a range of loading conditions and frequencies was found to occur at a critical cumulative strain, governed by a creep rupture process; the cyclic lifetime for both fibers is predictable using a simple creep rupture based theory. Polyester is more resistant to creep rupture, and consequently outperforms nylon 6,6 in cyclic fatigue. The advantage of polyester is considerably greater in aqueous solutions, where the performance of the nylon is diminished. Other comparisons indicate that the particular polyester fibers studied have higher stiffness and strength, lower strain to failure, and much lower hysteresis energy absorption compared with the nylon. The actual fatigue performance of complex fiber assemblies such as ropes is also limited under many conditions by factors not present in single fiber or yarn fatigue, including hysteric heating and internal and external abrasion.  相似文献   

17.
以废旧涤棉军装为原料,采用稀酸法分离废旧涤棉混纺织物中的涤纶和棉纤维,考察了盐酸浓度、反应温度、反应时间等工艺条件对涤、棉的分离效果以及分离后涤纶、棉纤维的形貌及结构性能的影响。结果表明:当盐酸质量分数10%,反应温度90℃,反应时间90 min时,废旧涤棉军装中的涤纶与棉纤维分离效果最佳;经盐酸处理后,织物中剩下涤纶,棉纤维被去除,棉纤维小部分降解为还原性糖,大部分降解为棉渣粉末;盐酸处理后的涤纶化学结构、断裂强度、纤维形貌基本无变化,但初始模量显著下降;棉纤维经盐酸处理后形成的棉渣粉末仍为纤维素结构,但其结晶度有所提高。  相似文献   

18.
沈耿亮  李明 《橡胶工业》2016,63(6):376-380
依据输送带技术的新进展和新应用,分析输送带用织物和骨架材料的发展趋势,重点阐述芳纶高强力输送带的特性、开发和应用前景。提出为响应国家节能、环保政策,未来输送带的发展方向是功能化、低能耗、长距离、高强度、长寿命。  相似文献   

19.
The solubility parameters of a BMC composite material, its polyester matrix, and its low profile additive [poly(vinyl acetate)] were determined by using several methods. For Hildebrand's solubility parameter : calculation from molar additive laws and determination from unrelaxed elastic constants, these latter being determined from the propagation rate of ultrasonic waves. For partial solubility parameters from sorption test in saturated solvent atmosphere, using bidimensional solubility maps. The effect of glass fibers and mineral fillers on solvent absorption can be considered negligible. In contrast, the presence of the low profile additive significantly modifies the solubility parameter values. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 2663–2671, 1998  相似文献   

20.
Since the physical modeling method for the desiccant wheel system (DWS) is complex and costly for calculations, the modeling method based on neural network (NN) gains attention for its simplicity and effectiveness. The previous NN models of DWS are mostly based on backpropagation (BP) NN and adopt the gradient searching method to obtain the weights and thresholds. However, the gradient searching method results in “overfitting” easily. In this paper, a novel neural network training algorithm, trainmpga, is proposed. The algorithm searches the optimal weights and thresholds of NN by making use of the multiple population genetic algorithm, thereby conquering the “overfitting” of the gradient searching method and the “prematurity” of the genetic algorithm. Meanwhile, related configurations of NN, such as parameters and framework, are studied. Finally, the proposed modeling method trainmpga proves to have high training and prediction accuracy in comparison to the training algorithms in the MatLab toolbox and has good application prospects.  相似文献   

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