• 멤브레인
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• 제26권3호
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• pp.212-219
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• 2016

알루미나 분말이 분산된 고분자용액을 비용매 유도 상전이법으로 방사 및 소결하여 알루미나 중공사막을 제조하였다. 용매-비용매의 상호작용 속도에 따른 중공사막 기공 구조 형성을 확인하고, 특성을 분석하기 위해 dimethylsulfoxide (DMSO), dimethylacetamide (DMAc), triethylphosphite (TEP) 용매를 사용하여 방사액을 제조하였으며, 고분자 바인더로는 polyethersulfone (PESf), 첨가제로는 polyvinylpyrrolidone (PVP)를 사용하였다. 알루미나 중공사막의 기공 구조 변화를 확인하기 위해 SEM으로 중공사막 단면을 분석하였다. DMSO, DMAc 용매를 사용할 경우 지상 구조(finger-like structure)와 망상 구조(sponge-like structure)가 복합된 기공 구조가 나타났으며, TEP 용매를 사용할 경우 전체적으로 망상 구조를 가졌다. 기공 구조에 따른 중공사막의 특성을 확인하기 위해 기체투과도, 기공도 및 기계적 강도를 측정하였다. 망상 구조를 갖는 중공사막은 높은 기체 투과특성을 보였으며 지상 구조가 증가할수록 기체투과도가 감소하였다. 반대로 기계적 강도는 지상 구조가 발달할수록 증가하였다.

• Advanced Composite Materials
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• 제16권4호
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• pp.269-282
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• 2007

Fully biodegradable high strength composites or 'advanced green composites' were fabricated using yearly renewable soy protein based resins and high strength liquid crystalline cellulose fibers. For comparison, E-glass and aramid ($Kevlar^{(R)}$) fiber reinforced composites were also prepared using the same modified soy protein resins. The modification of soy protein included forming an interpenetrating network-like (IPN-like) resin with mechanical properties comparable to commonly used epoxy resins. The IPN-like soy protein based resin was further reinforced using nano-clay and microfibrillated cellulose. Fiber/resin interfacial shear strength was characterized using microbond method. Tensile and flexural properties of the composites were characterized as per ASTM standards. A comparison of the tensile and flexural properties of the high strength composites made using the three fibers is presented. The results suggest that these green composites have excellent mechanical properties and can be considered for use in primary structural applications. Although significant additional research is needed in this area, it is clear that advanced green composites will some day replace today's advanced composites made using petroleum based fibers and resins. At the end of their life, the fully sustainable 'advanced green composites' can be easily disposed of or composted without harming the environment, in fact, helping it.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1997년도 춘계학술발표회 논문집
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• pp.11-15
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• 1997

• Journal of Microbiology and Biotechnology
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• 제25권11호
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• pp.1871-1879
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• 2015

The complex roles of flagella in the pathogenesis of Campylobacter jejuni, a major cause of worldwide foodborne diarrheal disease, are important. Compared with the wild-type, an insertional mutation of the flgA gene (cj0769c) demonstrated significant decrease in the biofilm formation of C. jejuni NCTC11168 on major food contact surfaces, such as polystyrene, stainless steel, and borosilicate glass. The flgA mutant was completely devoid of flagella and non-motile whereas the wild-type displayed the full-length flagella and motility. In addition, the biofilm formation of the wild-type was inversely dependent on the viscosity of the media. These results support that flagellar-mediated motility plays a significant role in the biofilm formation of C. jejuni NCTC11168. Moreover, our adhesion assay suggests that it plays an important role during biofilm maturation after initial attachment. Furthermore, C. jejuni NCTC11168 wild-type formed biofilm with a net-like structure of extracellular fiber-like material, but such a structure was significantly reduced in the biofilm of the flgA mutant. It supports that the extracellular fiber-like material may play a significant role in the biofilm formation of C. jejuni. This study demonstrated that flgA is essential for flagellar biosynthesis and motility, and plays a significant role in the biofilm formation of C. jejuni NCTC11168.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1987년도 제2차학술발표초록집
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• pp.12-13
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• 1987

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.241-242
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• 2009

본 연구에서 초고강도 콘크리트에 높은 연성을 얻기 위하여 Steel Fiber을 혼입하여 초고성능 콘크리트를 연구하였다. 기존의 Steel Fiber 와 Liquid Metal Fiber를 혼합한 초고강도 모르타르 시험체를 휨강도실험을 통하여 결과를 비교 검토 하였다. ASTM C 1018 방법, JSCE- SF4방법으로 인성지수 평가를 통해 Liquid Metal Fiber은 기존의 Bundrex Steel Fiber 보다 우수한 결과를 얻었다.

• 패션비즈니스
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• 제11권5호
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• pp.155-164
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• 2007

Viscose rayon has advantages such as vivid luster, good dyeability, low static electricity, good absorbance and good spinnability but also has flaws such as easy crease and decrease of physical properties when it gets wetting, and it requires dry cleaning. Therefore in order to synthesize the polymer to solve the problems of rayon while keeping the advantages of it, this study made the high specific gravity polyester for ultra drape property and high contraction polyester for rayon-like fiber having volume, soft and warm sense. The polyester with high specific gravity, 1.47 was made by adding 7 wt% of $BaSO_4$ as additive. High contraction polyester was made by copolymerization by using IPA 5 mole% to increase the amorphous region as comonomer and also using Newpol BPE-20(NPE) 1.5 wt% not to decrease the properties.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.57-60
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• 2003

Generally, normal concrete has the disadvantages of low tensile strength, low ductility and volume instability. To improve its performance, fiber reinforced cimentitious composite(FRCC) have been development. These composites are composed of cement, sand, water, a small amount of admixtures, and an optimal amount of fiber like synthetic fiber and steel fiber. This research investigates influence of sand, hybrid fiber and fiber volume fraction, and reports the test results of mechanical properties, fracture behavior and failure pattern of the FRCC. Our experiment was observed that sand mixed FRCC has lower compressive strength and higher bending strength than no sand mixed FRCC, and more steel fiber mixed FRCC has higher compressive strength and bending strength. Hybrid FRCC of steel and polypropylene had superior properties than FRCC of polypropylene only in same fiber volume fraction.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.59-62
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• 2003

Kinds, shapes and fraction ratios of fibers have influence on properties of HPFRCC(High-Performance Fiver Reinforced Cementitious Concrete ) like bending strength, strain capacity and fracture toughness. For example, hydrophilic fibers have different chemical bond strength from hydrophobic fibers, fiber shapes influence on fiber pull-out and rupture, and fiber volume fraction influence on bending strength. In this study, to estimate influences of kinds, shapes and fraction ratios of fibers, we make HFRCC with 3 kind of fiber in various volume fraction of fiber and compare cracking, bending strength and fracture toughness. As the results, bending strength of HPFRCC was increased as fiber volume fraction was Increase and fiber tensile strength was increase, and strain capacity and fracture toughness of HFRCC was higher in fiber pull-out fracture than in fiber rupture fracture. And HFRCC showing pseudo strain hardening has higher fiber reinforce efficiency than others.

• 한국미생물·생명공학회지
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• 제18권3호
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• pp.221-226
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• 1990

Bacillu circulans F-2를 포함한 B.circulans의 prophage와 bacteriocin을 검출하기 위하여, mitomycin C를 처리하고 전자현미경상, plaque 형성능(plaque-forming activity), 세균세포살균능(killing activtiy)을 실험했다. killing activity 양성균으로부터 서당밀도균배원심(sucrose gradient centrifugation)을 통해 bacteriophage-like particle의 존재를 확인하였다. 이들 입자들은 형태학적으로 phage tail 또는 T4 phage와 닮은 구조를 가지고 있었다.