• 대한환경공학회지
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• 제35권10호
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• pp.743-748
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• 2013

본 연구의 목적은 수분이 함유된 한지의 수분을 에탄올, 메탄올, 펜탄 등과 같은 비극성물질로 치환하여 한지 여과지를 만드는데 있다. 실험은 적정 비극성물질의 선택 및 적정 건조방법 그리고 제조된 한지여과지의 물리화학적 특성을 알아보기 위하여 수행되었다. 한지 종이필터를 제조하기 위하여 한지에 함유된 수분을 치환하기 위한 최적 물질은 에탄올이었으며 적정한 건조방법은 냉동 후 진공에 의해 수분을 건조하는 냉동건조방법이었다. 냉동건조에 의해 제조된 필터의 겉보기 밀도는 0.11-0.13 g/mL 으로 자연건조방법의 절반 이었으며 공극율은 약 90%로서 다공성을 나타내었다. 전자현미경 관찰결과 자연건조 및 열건조에 의해 제조된 여과지의 섬유는 섬유끼리 매우 가깝게 밀착되어 있었으나 냉동건조에 의해 제조된 섬유는 섬유간에 간격이 이격되어 있었다. 제조된 여과지의 압력손실은 자연건조 및 열건조 여과지보다 냉동건조에 의해 제조된 한지가 매우 낮았으며 BTEX제거효율은 한지의 수분을 비극성 물질에 의해 치환한 것보다 자연건조시킨 한지가 우수하였다.

• 한국염색가공학회지
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• 제30권3호
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• pp.208-215
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• 2018

The objective was to investigate the efficacy of Metasequoia(Metasequoia glyptostroboides) cone colorants as a new functional dye for wool fiber. Effects of dyeing conditions and mordanting on dye uptake, color change, and colorfastness were investigated for wool fiber. Compared with cotton and silk fibers, wool fiber showed better affinity for the Metasequoia cone colorants. Fe and Cu mordants improved dye uptake, and mordanting did not change the color of dyed fabric with YR Munsell color. Colorfastness to rubbing and washing was as good as grade 4, whereas lightfastness of the dyed fabrics was above grade 3. Antimicrobial activity of the colorants was very high 99.3% of reduction rate toward S. aureus. It was confirmed that Metasequoia cone colorants can be utilized as a new functional natural dye for wool fiber. In addition, considering its high antimicrobial functionality it could be applied to cosmetics and food.

• 펄프종이기술
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• 제40권1호
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• pp.62-67
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• 2008

Biocomposite was fabricated with biodegradable polymer and natural fiber that has potential to be used as replacement for glass fiber reinforced polymer composite with the benefits of low cost, low density, acceptable specific strength, biodegradability, etc. Until now, mostly natural cellulosic fibers on land have been used as reinforcement for biocomposite. The present study focused on investigating the fabrication and the characterization of biocomposite reinforced with red algae fibers from the sea. The bleached red algae fiber (BRAF) showed very similar crystallinity to the wood cellulose. It has high stability against thermal degradation (maximum thermal decomposition temperature of 359.3$^{\circ}C$) and thermal expansion. Biocomposites reinforced with BRAF have been fabricated by a compression molding method and their mechanical and thermal properties have been studied. The storage modulus and the thermomechanical stability of PBS (polybuthylenesuccinate) matrix are markedly improved by reinforcing with the BRAF. These results indicate that red algae fiber can be used as an excellent reinforcement of biocomposites, which are sometimes called as "green-composites" or "eco-composites".

• Journal of the Korean Wood Science and Technology
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• 제50권6호
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• pp.392-403
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• 2022

Currently, composite board manufacturing using natural fibers has the potential to expand owing to environmental awareness. To produce a composite board, treatment is required to improve the mechanical and physical properties of the natural fibers. In this study, sodium chloride (NaCl) was used for the chemical treatment. However, studies on chemical treatments using NaCl are limited. This study aimed to investigate the characteristics of kenaf fibers after NaCl treatment. The NaCl treatment concentrations were 1, 3, and 5 wt.% at room temperature, with soaking durations of 1, 2, and 3 h. The tensile strength, strain, and Young's modulus were measured to evaluate the mechanical properties of the fibers. The fiber bundle diameter, weight change owing to treatment, and contact angle were determined to analyze the effect of NaCl treatment. The kenaf fiber bundle treated with 5 wt.% NaCl for 3 h exhibited the highest tensile strength, Young's modulus, reduction in fiber bundle diameter, weight change, and decrease in contact angle compared to those of untreated fiber bundles. The tensile properties of the fiber bundle exhibited a tendency to decrease with increasing fiber bundle diameter. Increasing the soaking duration from 1 to 2 h did not result in a significant decrease in the fiber bundle diameter or an increase in tensile strength. However, a further increase in the soaking duration from 2 to 3 h resulted in a considerable decrease in the fiber bundle diameter and an increase in the tensile strength.

• 한국식품조리과학회지
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• 제14권4호
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• pp.333-338
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• 1998

산마의 총 식이섬유가 2-AF와 MNNG에 대해서는 각각12.4%와 18.7%의 억제효과를 나타냈으며, 재배마는 33.2%와 49.1%의 억제효과를 보여 재배마의 $\alpha$-cellulose는 각각 0.5%, 1.0%농도에서 70.0%와 76.9%로 가장 높은 억제효과를 나타냈으며 MNNG에 대해서는 모든 농도에서 90% 이상의 억제효과를 나타냈다. Pectin의 2-AF에 대한 억제효과는 산마의 경우 0.1% 농도일 때 42.5%로 가장 높았고, 재배마는 억제효과를 나타내지 않았다. MNNG에 대해서는 산마 1.0%와 재배마 0.7% 농도일 때 각각 51.8% 와 31.0%로 가장 높은 억제효과를 나타냈다. 반응 시간에 따른 억제 효과는 2-AF에 대해 산마, 재배마 및 표품의 $\alpha$-cellulose (0.5%)는 3시간일 때, MNNG에 대해서는 6시간일 때 최고의 억제 효과를 나타냈다. 산마, 재배마 및 표품의 pectin(1.0%)의 2-AF에 대해 반응 시간이 경과함에 따라 억제 효과가 점진적으로 감소하였으며 MNNG에 대해 1시간 30분일 때 높은 억제 효과를 나타냈다. 산마와 재배마에서 추출한 $\alpha$-cellulose와 pectin은 2-AF에 의해 유발되는 돌연변이원성에 비해 MNNG에 의해 유발되는 돌연변이원성을 더 효과적으로 억제하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.251.1-254
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• 2001

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.327-330
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• 2000

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.351-355
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• 2000

• 한국응용과학기술학회지
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• 제26권1호
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• pp.51-59
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• 2009

Natural Artemisia extraction was extracted from Artemisia component using diethyl ether as a solvent, and we tested various pharmacetical and chemical characteristics of this extract. Characteristic experiments to use natural Artemisia extract tested antimicrobial experiment using microbe in pharmacetical material, and tested dye experiment using fiber in chemical material. From the result of characteristics experiment, some conclusions are obtained as follow. From the result of extraction experiment, it obtained about 10.4%-Artemisia extraction ratio as semi-solid state, and after dried in freezing from Artemisia extract of semi-solid state, it obtained about 10%-Artemisia extraction ratio as solid state of dark blue-green color. From result of antimicrobial experiment of Artemisia extract, number of staphylococcus aureus (ATCC-01) and aspergillus niger (ATCC-02) in microbe decreased more and more according to time passage. This phenomenon showed that Artemisia extract influences to antimicrobial effect. From the result of dye experiment of Artemisia extract, it appeared in direction of dark blue-green color after dyed to use cotton and silk with fiber to control in pH 7.5. Specially the result which confirmed dye of fiber with optical electron microscope (OEM), we could know that it appears darker silk than cotton.

• Structural Engineering and Mechanics
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• 제50권6호
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• pp.773-796
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• 2014

This paper deals with free vibration analysis of continuous grading fiber reinforced (CGFR) and bi-directional FG annular sector plates on two-parameter elastic foundations under various boundary conditions, based on the three-dimensional theory of elasticity. The plates with simply supported radial edges and arbitrary boundary conditions on their circular edges are considered. A semi-analytical approach composed of differential quadrature method (DQM) and series solution is adopted to solve the equations of motion. Some new results for the natural frequencies of the plate are prepared, which include the effects of elastic coefficients of foundation, boundary conditions, material and geometrical parameters. Results indicate that the non-dimensional natural frequency parameter of a functionally graded fiber volume fraction is larger than that of a discrete laminated and close to that of a 2-layer. It results that the CGFR plate attains natural frequency higher than those of traditional discretely laminated composite ones and this can be a benefit when higher stiffness of the plate is the goal and that is due to the reduction in spatial mismatch of material properties. Moreover, it is shown that a graded ceramic volume fraction in two directions has a higher capability to reduce the natural frequency than conventional one-dimensional functionally graded material. The multidirectional graded material can likely be designed according to the actual requirement and it is a potential alternative to the unidirectional functionally graded material. The new results can be used as benchmark solutions for future researches.