• Advances in nano research
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• v.14 no.5
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• pp.443-450
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• 2023

Carbon nanotubes (CNTs) have received increased interest in reinforcing research for polymer matrix composites due to their exceptional mechanical characteristics. Its high surface area/volume ratio and aspect ratio enable polymer-based composites to make the most of its features. This study focuses on the experimental tensile testing and fabrication of carbon nanotube reinforced composite (CNTRC) beams, exploring various micromechanical models. By examining the performance of these models alongside experimental results, the research aims to better understand and optimize the mechanical properties of CNTRC materials. Tensile properties of neat epoxy and 0.3%; 0.4% and 0.5% by CNT reinforced laminated single layer (0°/90°) carbon fiber composite beams were investigated. The composite plates were produced in accordance with ASTM D7264 standard. The tensile test was performed in order to see the mechanical properties of the composite beams. The results showed that the optimum amount of CNT was 0.3% based on the tensile capacity. The capacity was significantly reduced when 0.4% CNT was utilized. Moreover, the experimental results are compared with Finite Element Models using ABAQUS. Hashin Failure Criteria was utilized to predict the tensile capacity. Good conformance was observed between experimental and numerical models. More importantly is that Young' Moduli of the specimens is compared with the prediction Halpin-Tsai and Mixture-Rule. Although Halpin-Tsai can accurately predict the Young's Moduli of the specimens, the accuracy of Mixture-Rule was significantly low.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.6
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• pp.1138-1150
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• 1996

This study was carried out to investigate the effects of dyeing on the mechanical properties, primary hand, total hand value (THV), and total appearance value (TAV) of woven fabrics. Cotton, PET, nylon, cotton/PET, and cotton/nylon woven fabrics were used as test specimens. Each of fabric was dyed under the same conditions as the fabrics for sportswear which consumers have selected as best. Mechanical properties of specimens were measured by KES-FB system and primary hand and THV were calculated by equation KN -201-MDY and KN-301-WINTER respectively. TAV was calculated by KN (eq. 10). The results were as follows: 1. In mechanical properties. tensile energy increased when cotton and two cotton mixture fabrics were dyed and decreased when polyester and nylon fabrics were dyed. Bending rigidity and shear rigidity decreased after all fabrics were dyed except nylon and cotton/ nylon mixture fabrics showing higher rigidities. Cotton fabrics showed higher surface roughness while other fabrics did lower values after dyeing. 2. In evaluation of primary hand and total hand , four primary hands of cotton fabrics so decreased after dyeing that THV were lowered. Numeri, Fukurami, and Sofutosa in primary hand of polyester, cotton/polyester, and cotton/nylon fabrics and Koshi and Numeri of nylon fabrics increased after dyeing and therefore THV of four fabrics were improved. 3. Cotton and polyester fabrics showed higher TAV due to their lower bending and shear rigidity, while nylon and cotton/nylon fabrics did lower values due to their higher shear rigidity. 4. It was proposed that the method of dyeing or treatment for minimizing the decrease of THV of cotton fabrics and TAV of nylon fabrics should be developed.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.4
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• pp.137-146
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• 1996

This paper presents the results of field experience from an experimental pavement construction on a low volume road using recycled concrete. The recycled concrete was prepared by replacing a half of coarse aggregate with recycled aggregate. Virgin natural sand was used as fine aggregate together a plasticizer and a fly ash (0.8% and 5% by wt. of cement, respectively). The load bearing capacity of the subbase made of recycled aggregate was acceptable. The length, thickness and width of the pavement were l00m, 20cm and 3m, respectively. From construction experience, it was found that workability and finishability of the recycled concrete mixture were relatively poor, but strengths were satisfactory. Flexural strength, compressive strength and elastic modulus at 28 days were 54Kg/$cm^2$, over 250Kg/$cm^2$, and 220,OOOKg/$cm^2$, respectively. The construction could be performed by hand without much difficulty. The surface was finished smoothly by wet fabric and only minor cracks were found on the surface.

• Fibers and Polymers
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• v.5 no.3
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• pp.230-233
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• 2004

The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA) and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.8
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• pp.1079-1089
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• 1998

Various fabrics, including natural fibers, regenerated cellulosic fibers, synthetic fibers, blend yarn, and mixture fabrics, were treated with the solutions of high purity chitosan in 1% acetic acid, having high viscosity of 930cps or low viscosity of 8cps. Physical/ mechanical properties of the treated fabrics samples were measured using Kawabata Evaluation System and drape tester. From these, hand values and total hand values of the fabric samples were calculated using Kawabata-Niwa translation equations. KOSHI, SHARI, HARI values have increased for the treated samples, while FUKURAMI values have decreased in general.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.388-393
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• 1996

This study evaluated characteristics and performance of recycled concrete as a pavement which was constructed on a low volume road. The recycled concrete was prepared by replacing a half of coarse aggregate with recycled aggregate. Natural sand from a source was used as fine aggregate together with admixtures such as plasticizer and fly ash (0.8% and 5% by wt. of cement, respectively). The length, thickness and width of the pavement were 100mm, 20cm and 3m, respectively. From construction experience, it was found that workability and finishability of the recycled concrete mixture were relatively poor, but strengths were satisfactory. Flexural strength, compressive strength and elastic modulus at 28 days were approximately 45Kg/$\textrm{cm}^2$, 250Kg/$\textrm{cm}^2$, and 240,000 Kg/$\textrm{cm}^2$, respectively. The pavement could be constructed by hand without much difficulty. The surface was finished smoothy by wet fabric and only minor cracks were found on the surface.

• Journal of the Korean Society of Costume
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• v.59 no.3
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• pp.145-156
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• 2009

This study proposes the product development through an organic link with multi-faceted analysis on the archetype of traditional costumes culture. In order to find ways to develop cultural products, Jogakbo was selected, and the research result is as following. 1. Analysis on the types of Jogakbo products sold in the market shows that there are not only living, stationary, and fashion items, but also DIY packages. In terms of materials used, most of these Jogakbo products were made of fabric or mixture of different materials. These products displayed similar tendency by reflecting formative characteristics of Jogakbo. 2. This study analyzed the color, surface composition, material, manufacturing, and usage of Jogakbo. The rotor of Jogakbo is mostly composed of mono tone colors or Obangsac(five-element colors). The mono tone colors carries environmentally friendly meaning as it is using the natural color and Obangsac means harmony. Moreover, the surface composition of Jogakbo represents the expansion through connection and its material is also meaningful in that it is recycling. Manufacturing of Jogakbo has educational significance, fortune-wishing characteristics, decorative function, it also gives a gratification of handcraft. The usage of Jogakbo is a multi-(unctional article whose form is determined by an item that is held inside it. 3. Through the analysis on Jogakbo, this study presents the baby wear in relation to the ere-friendliness of colors, brooch sets using the surface composition, dresses using recycling fabric, children's educational instruments with educational significance, as well as multi-functional packages in regards to usage of Jogakbo.

• Journal of the Korean Society of Clothing and Textiles
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• v.13 no.3 s.31
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• pp.286-294
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• 1989

This Study has treated the effects of fiber, surfactants, temperature, surfactant concentration, pH, electrolyte, fatty acid contents and mechanical force on the removal of particulate soil from fabric, vacuum cleaner dirt was used as model particulate soil. The fabrics were soiled with mixture of vacuum cleaner dirt and fatty soil, and washed in Terg-O-tometer. The detergency was evaluated by measuring reflectance of a fabric before and after washing. The results were as follows. 1. The fiber type showed a different pattern of soil removal with surfactants. In general, particulate soil removal increased in the following order Acetate>PET. Nylon>Cotton. Particulate soil removal, which is affected by the surfactant type, increased in the following order NPE $(EO)_{10}\leqq$Soap>SLS>DBS>Tween 80. 2. The influence of temperature on the particulate soil removal was very complex because efficiency of removal was varied with surfactant and fiber types. The washing efficiency of NPE $(EO)_{10}$ was highest at around $40^{\circ}C\;and\;60^{\circ}C$ with cotton and PET but the washing efficiency of DBS was the highest at $60^{\circ}C$ with cotton, decreased monotonously with increasing temperature with PET 3. The detergency of particulate soil increased with increasing surfactant concentration at relatively low concentration and then levelled off above some optimum concentration. 4. The removal of particulate soil increased with increasing pH and mechanical force. 5. Effect of electrolyte on the particulate soil removal was depended on the concentration of the surfactant. At low concentration of surfactant, addition of electrolytes improved soil removal but above the some concentration no effect was observed. At high concentration of surfactant, Vie., $0.6\%$ , the maximum washing effect is reached without added electrolyte. These result indicate that added electrolyte only influence the adsorption of surfactant on the soil and fiber 6. Fatty acid content in the soil did not influence on particulate soil removal without regard to surfactants.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2005.06a
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• pp.245-247
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• 2005

A cellulolytic fungus isolated from Agave plantation in northeastern Thailand was identified as Acrophialophora nainiana. The fungus was capable of growing at pH between 3 - 7 and 25 - 45 $^{\circ}C$, with the optimum conditions at pH 5.0 and 40 $^{\circ}C$. The wild isolate produced cellulases, comprising of exoglucanase (0.019 U/mg protein), endoglucanase (0.366 U/mg protein), and ${\beta}$-glucosidase (0.001 U/mg protein). Mutations with UV and NTG produced the UV 10-2 mutant with cellulases activities including exoglucanase (0.093 U/mg protein), endoglucanase (0.585 U/mg protein), and ${\beta}$-glucosidase (0.013 U/mg protein). Purification of the enzymes with ultrafiltration, ammonium sulfate precipitation, and ion-exchange chromatography yielded the maximal cellulase specific activities of 2.736 U/mg protein (exoglucanase), 0.235 U/mg protein (endoglucanase), and 0.008 U/mg protein (${\beta}$-glucosidase). The mutant's cellulases were the most active at pH 5.0 and 60 $^{\circ}C$. Ion-exchange chromatography revealed that A. nainiana UV 10-2 cellulases were comprised of two peaks with one peak showing the single endoglucanase activity while the other peak showed a mixture of the three enzyme activities. Production of A. nainiana UV 10-2 cellulases using banana leaf stalk as the sole carbon source gave comparable yields to that of the pure ${\alpha}$-cellulose. The enzymes were used in the simultaneous saccharification and fermentation (SSF) of plant residue (Coix aquatica) along with Kluveromyces marxianus to produce ethanol. Moreover, when the enzymes were used in the bioscouring process of fabric, the desiravle traits of textile processing including immediate water absorbency, increased in whiteness and reduction of yellowness of the treated fabric were observed.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.1 s.149
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• pp.115-124
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• 2006

Natural dyes are environmentally and human compatible. But they are not various or not fast in color. The mixed dyeing have been attempted to solve these disadventages of natural dyes. The persimmon juice dyed fabrics have brown-color and good hygienic properities however low color fastness. The onion dyeing show similar brown-color and have good color fastness caused by querectin existed in onion outer skins. Mixed dyeing was carryied out on silk fabrics using persimmion juice and onion outer skin extract in this study. The mixing method were persimmon juice dyeing and then onion dyeing(P-O), onion dyeing and then persimmon juice dyeing(O-P) and dyeing in the mixture of persimmon juice and onion outer skin extract simultaneously(P+O). The mordants were none-mordent, gallic acid after-treatment and alum after-treatment. Several persimmon juice dyed fabrics were irradiated for 2 hours before onion dyeing(PU-O). The color values of dyed silk fabrics were as follows. The persimmon juice dyed silk fabric developed to yellow-red color after 2 hours of uv irradiation. Onion dyed fabrics show similar yellow-red color after dyeing without uv irradiation. The effect of alum after-treatment on color difference were highest in onion dyeing. The dyeabilities of both P-O and O-P were higher than persimmom juice dyeing and onion dyeing. The dyeabilities of P+O was lower than persimmom juice dyeing and onion dyeing. The value of color difference of alum-treated fabric was the highest. The color difference of P-O and O-P caused from 2 to 4 hours of uv-irradiation were lower than those of persimmon juice dyed fabrics. Onion skin extract could prevent the color-change of persimmon juice dyed fabrics in mixed dyeing. The color difference of PU-O was higher than the P-O.