فصلنامه علوم و فناوری نساجی
سال سوم شماره 1 (بهار 1392)

Nowadays، the fashion industry is a global industry in which most countries invest in it. In recent years by development of e-commerce and its time saving and providing wide selection of goods for customers، many people do their purchasing through online shops instead of going to stores. So for the online apparel markets، it is necessary to have a system to retrieve garment images and include them in a specific database، so to do searching quicker and more effectively. In this way customers find it easier to have access what they look for. Although it is simple to detect a garment style by image searching but it is no so for a computer system. In this paper an algorithm is presented which is based on image processing and K-means clustering for grouping the garment images. The algorithm has the ability to group similar garment images. The results show that this developed system can detect and cluster 67% of database images correctly.

Braided and filament-wound tubular composites were produced by various glass fiber preform structures on a cylindrical mandrel using a modified maypole braiding machine. The composites were then impregnated with unsaturated polyester resin by vacuum infusion process (VIP). After performing compression test on the samples and calculating the failure force and failure energy، it was observed that the filament-wound sample displayed higher compression properties than those of braided samples with the same fiber volume percent. This was due to having more reinforcing layers with more reinforcing strands for compensating the effect of waviness in its braided counterpart. The results showed that the braided samples، with the same number of layers with the filament-wound tubes but different fiber volume percentage، show the highest compression failure force and energy. The reason for this phenomenon was attributed to higher tube wall thickness in the braided sample and consequently more stable behavior during compression loading.

Polyamide nanofibers (nylon 6) were fabricated as core-shell structures with enriched silver nanoparticles in their shells. The main purpose of this study was to produce nanofibers with reduced silver nanoparticles content while maintaining or enhancing their antibacterial effectiveness. The coaxial electrospinning was used to fabricate the nanofibers. The core-shell solutions consisted of polyamide (caprolactam) in formic acid or acetic acid and adding silver nanoparticles into the solutions. The morphology of samples was characterized by scanning electron microscope (SEM) and the AATCC100 standard test method was used to determine the antibacterial properties of the fibers. EDAX was used to test the presence of silver nanoparticles in the samples. Finally، the new fibers'' antibacterial quality was tested on Gram (-) bacteria E. Coli and Gram (+) bacteria S. Aureus. The results showed that the core-shell nanofibers were successfully produced with uniform concentration of silver nanofibers in their shells and displayed the same degree of antibacterial activity as samples with uniform distribution of nanoparticles in both the core as well as the shell structures.

Mercerization of cotton fabrics leads to improved tensile strength، dye absorption، chemical reactivity، dimensional stability and luster of the fabrics. Due to lack of sufficient information، in this research the interactive parameters such as temperature and alkali concentration were investigated on mercerization of cotton fabrics. Mercerizing was carried out under different temperatures، within temperature range of 15-90ºC and variable concentrations of sodium hydroxide in both slack state and under tension. After mercerization process the fabric samples were bleached and then dyed with a reactive dye. The effects of treatment were investigated using different test methods. Tegewa test was used to evaluate the quantity of removed starch from the samples mercerized under different conditions. The changes in the samples surface structure because of treatment conditions were compared using electron microscopy. In addition، alkali treatments were studied with respect to fabrics performance under tested conditions of dye adsorption of the samples. The results indicate that there is an increase in the amount of starch removal due to increases in mercerization temperature with more effective removal from non-tension slack-mercerized fabrics as compared with those of slack-mercerized fabrics under tension. The obtained results also revealed that the increase in dye uptake was related to joint effects of temperature and alkali concentration in mercerization process.

Adsorption is an effective method for water and wastewater treatments. The adsorption process is widely used to remove dyes from colored wastewater due to its easy application and simple design. In addition the interesting aspect of adsorption is due to the transfer of target substances from solutions onto adsorbent surfaces. Traditional adsorbent materials suffer from some disadvantages such as poor separation ability and relatively limited adsorption capacity for dyes. Thus researchers have found interest in new adsorbents. In this paper، dye removal ability of zinc-nickel ferrite nanoparticle type of material as a magnetic adsorbent was studied. Basic Blue 41 (BB41) and Basic Red 18 (BR18) were used as model dyes. Uv-vis spectrophotometer was used to follow and record the dye removal. The effect of adsorbent dosage and dye concentration on dye removal was studied. Direct dyes were removed from wastewater. Adsorption isotherm followed the Langmuir isotherm and the adsorption kinetics followed pseudo-second order. The results showed that zinc-nickel ferrite nanoparticle can be used as an effective magnetic adsorbent to treat colored wastewater.

Triethanol amine-based esterquats softener using stearin oil palm and soya beans oil were synthesized by two different methods namely، microwave irradiation and conventional thermal methods at different temperatures. FTIR spectra، critical micelle concentration (CMC) and melting point were employed to investigate the chemical and physical properties of the synthesized softeners. Synthesized softeners were applied on three different fabrics such as 100% cotton، cotton-polyester (35%-65%) and wool-polyester (30%-70%) by different methods namely «exhaustion»، «pad-bach» and «pad-drycure». The softening power، wettability، yellowness، and anti-wrinkling properties of the synthesized softeners were evaluated. It was found that microwave synthesized softener possesses better softening، wettability and anti-wrinkling properties whilst shorter reaction time with higher yield، lower cost of the synthesized product were the other advantages of this method over the conventional thermal method and the results show that the synthesized softeners display good softening، acceptable wettability and yellowness properties. By using the pad-dry-cure method the cellulose-based fabrics have suitable anti-wrinkle property.