• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3A
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• pp.251-260
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• 2011

In this study, the effect of natural jute fiber volume fraction on the bond characteristics of polyolefin based macro fiber in natural jute fiber reinforced cement composites, including bond strength, interface toughness, and microstructure analysis are presented. The experimental results on polyolefin based macro fiber pullout test of different conditions are reported. Natural jute fiber volume fractions ranging from 0.1% to 0.2% are used in the mix proportions. Pullout tests are conducted to measure the bond characteristics of polyolefin based macro fiber from natural jute fiber reinforced cement composites. Test results are found that the incorporation of natural jute fiber can effectively enhance the polyolefin based macro fiber-cement matrix interfacial properties. The bond strength and interface toughness between polyolefin based macro fiber and natural jute fiber reinforced cement composites increases with the volume fraction of natural jute fiber. The microstructural observation confirms the findings on the interface bond mechanism drawn from the fiber pullout test results.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.314-320
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• 2022

The function of reinforcing fibers used in building materials is to maintain resistance to bending loads and to function for cracking caused by drying shrinkage. High-density fiber-cement composites are mainly used for linear plates and are used to increase bending resistance. Therefore, tensile properties, bonding strength with cement hydrate, alkali resistance, and the like are required. Recently, as the non-combustible performance has been strengthened, a function to minimize the occurrence of sparks during high-temperature heating has been added. Therefore, the use of organic fibers is limited. In this study, a study was conducted to replace polypropylene used as reinforcing fiber with hemp fiber with excellent heat resistance. Hemp fibers have excellent heat resistance, good affinity with cement, and excellent alkali resistance. Based on the total volume of polypropylene fibers used in the existing formulation, the non-combustible performance was compared and evaluated by using hemp fibers instead of the polypropylene fibers, and basic physical properties such as flexural strength were tested. As a result of conducting a non-combustibility and physical property test using hemp fibers with a fiber length of 7 mm using 2 % and 3 % by weight, it was found that there is no remaining time of the flame, and the flexural strength can be secured at 95 % level of the existing polypropylene fiber.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.281-284
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• 2002

마 섬유는 흡습성이 좋고 건조가 빠르고, 습윤 시 강도가 증가되며 열전도율이 크고 통기성이 크며, 강도와 내열성이 천연 섬유 중 가장 우수하며 매끄러운 표면을 가지고있어서 광택과 방오성이 좋다. 그러나 세사방적이 어렵고 강연도가 지나치게 커서 의복소재로서 극히 제한적으로 사용되어왔으나, 최근에는 큰 강연도를 장점으로 활용하여 여름용 의복소재로 다시 각광받고 있다. 따라서 면, 레이온, 셀룰로오스계 섬유제품들에 대하여 마 제품과 유사한 효과를 낼 수 있는 다양한 의마가공법이 개발되어왔다[1,2]. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 1997.04a
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• pp.165-169
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• 1997

• Proceedings of the Korean Fiber Society Conference
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• 1997.10a
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• pp.373-376
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• 1997

• Journal of the East Asian Society of Dietary Life
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• v.6 no.2
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• pp.277-284
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• 1996

The objective of this study was to screen the antimutagenicity of yam enzymatic browning reaction product (YEBRP), mucopolysaccharide and dietary fiber from yam to the mutagen of sodium azide and 2-aminoflourene (2-AF). Antimutagenicity of YEBRP on the mutagenicity of sodium azide showed no difference compared to control without YEBRP but that of 2-AF was high In all substrate. (P＜0.01) On the mutagenicity of sodium azide and 2-AF, antimutagenicity of mucopolysaccharide and dietary fiber were high (p＜0.01) in $\alpha$-cellulose and hemicellulose, Antimutagenicity of u-cellulose on the mutagenicity of 2-AF was high at 5 hours reaction time but that was decreased as the reaction time increased.

• Food Industry And Nutrition
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• v.17 no.2
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• pp.20-22
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• 2012

본 연구에서는 둥근마와 장마의 일반성분을 분석하여 둥근마의 우수한 성질을 밝히며, 에탄올 농도를 달리(0~95%, v/v)한 용매로 둥근마를 추출한 후 항산화활성을 측정함으로써 둥근마의 항산화성분을 최대한 함유할 수 있는 최적의 에탄올농도를 찾아, 이 추출물을 활용한 다양한 기능성 함유 음료의 제조방법을 개발하고자 하였다. 일반 성분 분석결과 둥근마의 경우 탄수화물, 열량, 단백질 및 철 함량이 장마와 비교하여 월등히 높은 값을 나타내었고, 식이섬유 및 칼륨 함량 또한 비교적 높았다. 47.5~95% (v/v) 에탄올 함유 용매로 추출할 경우 순수한 물로 추출한 경우보다 더 높은 항산화 활성을 나타내었다. 전자공여능의 경우 추출용매의 에탄올 농도가 높을수록 높은 값을 나타내었으며, 반면에 총 폴리페놀성 화합물함량의 경우 71.25% 농도의 에탄올로 추출한 추출액에서 가장 높은 값을 나타내었다. 따라서 에탄올농도 약 70~95% 정도의 용매로 추출한 둥근마 추출액 함유 음료를 제조함으로써 항산화 성분을 다량함유 한 음료를 제공할 수 있을 것이며, 또한 둥근마 추출액에 첨가물 및 기타 기능성 성분을 혼합하여 음료를 제조함으로써 기호성이 증가되고 기능성이 향상된 다양한 음료를 제공할 수 있을 것으로 사료된다.

• Journal of Life Science
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• v.20 no.9
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• pp.1365-1372
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• 2010

We investigated the inhibitory effects of solvent extracts from dried yam on $H_2O_2$-induced oxidative stress and growth of cancer cell lines (HT1080 human fibrosarcoma and HT-29 human colon cancer cells). Yam (Dioscoreacea) has been recognized as a healthy food due to its various biological activities, such as anti-obesity, anti-constipation, anti-proliferation, and anti-mutagenic activities, as well as its ability to decrease blood glucose and cholesterol levels. In order to determine the protective effect on $H_2O_2$-induced oxidative stress, DCFH-DA (dichlorodihydrofluorescin diacetate) assay was conducted. Acetone with methylene chloride (A+M) extract of dried yam appeared to reduce the levels of intracellular reactive oxygen species (ROS) with dose responses. Among the fractions, 85% aq. methanol fraction showed the highest protective effect on production of lipid peroxides. Inhibitory effects of A+M and methanol (MeOH) extracts on the growth of HT1080 and HT-29 cancer cells increased in a dose dependent manner. The treatments of n-hexane, 85% aq. methanol and n-butanol fractions (${\geqq}0.5$ mg/ml concentrations) significantly inhibited the growth of both cancer cells (p<0.05). From these results, 85% aq. methanol fraction showed inhibitory effects on cellular oxidation and growth of human cancer cells, suggesting that this fraction may contain active compounds of dried yam.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.123-126
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• 2002

섬유와 같은 고분자 물질의 생분해성은 그 분자의 화학적, 물리적 특성과 밀접한 관련이 있으므로 같은 셀룰로오스로 이루어진 섬유라고 해도 각각의 화학적 구조나 물리적 특성에 따라 분해 거동이 다를 수 있다. 면, 마, 레이온, 아세테이트 등은 모두 셀룰로오스계 섬유라는 공통점이 있으나 구조적 차이, 제조 공정의 차이, 그리고 분자의 화학 조성 등이 다르며, 함유되어있는 비셀룰로오스분의 종류 및 구성비가 다르다. (중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2A
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• pp.105-113
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• 2011

This study evaluated the effects of fibers on the mechanical properties and chemical solution resistance of porous concrete with fiber type (jute, pulp, PVA and nylon fiber) and fiber volume fraction (0.0%, 0.1%, 0.2%, 0.3%). The tests that were carried out to analysis the properties of porous concrete included compressive strength, void ratio, pH value, and chemical solution exposure with varying type and volume fraction of fiber were conducted. The type and volume fraction of fiber also affected the void ratio, compressive strength, flexural strength and chemical solution exposure. Increased volume fractions of fiber resulted in improved properties of the compressive strength, flexural strength and void ratio. However, the difference between the measured pH value and chemical resistance of porous concrete with fiber type and volume fraction was not significant.