• 한국의류학회지
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• 제35권1호
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• pp.115-124
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• 2011

This study provides an eco-friendly dyeing processing for chitosan fiber using Oenothera odorata jacquin as a dye. The effects of chemical mordants (Al, Cu, Fe) and natural mordant (Chestnut shell) on the color change for dyed chitosan fibers were measured by K/S values, L, $a^*$, $b^*$, H, V, C values, color fastness, and antimicrobial activity. The results are as follows. Dyeing conditions of Oenothera odorata jacquin on chitosan fibers were optimized to $70^{\circ}C$, 30 minutes and 200% on weight of fabric (o.w.f.). The pre-mordant concentration of aluminium (Al), copper (Cu) and iron (Fe) of chitosan fibers was optimized to 3% (o.w.f.) and 1% (o.w.f.), respectively. The post-mordant concentration of chemicals, such as Al, Cu and Fe, on chitosan was determined to 1% (o.w.f.). The hue of chitosan fibers by chemical mordants was measured to be reddish & yellow. The pre-mordant concentration of Chestnut shell of chitosan was optimized to 70% (o.w.f.). The post-mordant concentration of Chestnut shell on chitosan was determined to be 50% (o.w.f.). The hue of chitosan fibers by Chestnut shell mordant was measured to be reddish & yellow. The wet cleaning fastness of chitosan fibers was improved by a pre-mordant that used chemical mordants. In the case of the Chestnut shell mordant, the wet cleaning fastness was improved by a post-mordant. The dry cleaning fastness of chitosan fibers was excellent regardless of mordants and mordant methods. The antimicrobial activity of the chitosan fiber was shown at 99.9% and its excellent qualities remained after the dyeing and mordant processing.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.309-310
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• 2003

활성탄소 (activated carbons, ACs)는 넓은 비표면적을 가지고 있어 흡착용량이 크며, 발달된 미세공을 가지고 있기 때문에 오염물질의 제거능력이 높을 뿐만 아니라 경제적, 환경 친화적인 측면에서도 유리하다. 특히 섬유화된 할성탄소섬유 (activated carbon fibers, ACFs)는 균일한 세공이 표면에 노출되어 있어 흡착속도가 빠르며, 안정성과 재생성이 좋고 섬유상이기 때문에 가공이 용이하며 직포, 부직포, 시트 등의 형태로 만들어져 용매회수, 공업제품의 정제, 오폐수의 처리시설, 소각시설의 유해 배기가스의 흡착등에 널리 사용되고 있다.[1,2] (중략)

• 한국식품영양과학회지
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• 제39권7호
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• pp.1078-1082
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• 2010

본 연구는 해조류 세포벽에 결합된 무기질은 모두 이용되지 않는다는 전제하에 해조류의 세포벽물질(중성세제불용성섬유: neutral detergent fiber, NDF)을 측정하고 이에 결합된 미량 무기질 Fe, Cu, Zn, Mn의 함량을 조사하여 해조류내에 함유되어 있는 무기질 함량에서 빼줌으로써 계산하여 해조류의 무기질 이용률을 추정하였다. 해조류 총 7종에 대해, 해조류 100 g당 NDF에 결합된 무기질 Zn, Cu, Mn의 평균 함량은 각각 1.78, 0.43, 0.23 mg으로 그에 따른 이용률이 각각 90.56, 85.43, 87.26%로 모두 85% 이상의 높은 이용률을 나타냈다. 반면, Fe은 NDF에 결합된 무기질 함량이 22.42 mg/100 g으로 비교적 많은 양이 결합되어 있어 그 이용률은 68.36%로 낮은 이용률을 보였다. Fe이 NDF에 가장 많이 결합한다는 보고와 같이 해조류에서도 식이섬유인 NDF에 결합된 Fe의 함량이 많아 그 이용률은 상대적으로 낮았다. 하지만 그 외 Zn, Cu, Mn의 이용률은 85% 이상으로 높아 인체 내의 소화율을 고려한다 하더라도 이들 무기질은 높은 추정 이용률을 보일 것으로 판단되어 인체 영양상 미량 무기질의 좋은 식품자원으로써 그 이용을 기대해 본다.

• 한국환경보건학회지
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• 제27권3호
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• pp.107-112
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• 2001

This work reports the application of a hollow fiber module(HFM) for Cr(VI) extraction from heavy metal salts mixed solution by using microporous hydrophobic hollow fiber module. In HFM configuration, the organic extraction used for the extraction of Cr(VI) was di-(2-ethyl hexyl) phosphoric acid(D2EHPA) diluted with n-heptane. The study of HFM includes the influence of hydrodynamic and chemical condition, i.e., the flow rate of feed solution, the time of reactive extraction, the concentration of feed solution, and the pH of aqueous phase solutions. Several experiments with synthetic solution of different mixed components system of Cr(VI) solutions established optimum condition to achieve a clean separation of Cr(VI). It was possible to separate Cr(VI) in the presence of metal salts mixed solution, such as Zn(II), Ni(II), Cu(II), and Cd(II) using the HFM technique.

• 조명전기설비학회논문지
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• 제24권10호
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• pp.49-57
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• 2010

In order to provide electricity to users economically and safely, distribution automation systems (DASs) monitor and operate components of distribution systems remotely through communication networks. The fiber optic communication network has been mainly installed for the DAS of Korea Electric Power Corporation (KEPCO) because of its huge bandwidth and dielectric noise immunity. However, the fiber optic communication network has some shortcomings that its installation cost and communication fee are expensive. This paper proposes a complex network where WLANs are combined with conventional fiber optic communication networks in order to expand DAS easily and inexpensively. A fixed wireless bridge communication unit (FWB-CU) for the proposed complex network is implemented using IEEE 802.11a WLAN technology. The proposed complex network is built actually to verify its feasibility experimentally as a DAS communication network.

• Composites Research
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• 제34권1호
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• pp.47-50
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• 2021

본 논문은 차량에 사용되는 B필러의 강화재를 기존의 스틸 소재에서 CFRP(Carbon Fiber Reinforced Plastics)와 GFRP(Glass Fiber Reinforced Plastics)로 대체하여 경량화하는 것이 목표다. 이를 위해서는 무게는 감소시키면서 기존 B필러를 대체할 수 있는 구조안정성을 확보해야 한다. 기존 B필러는 스틸 아우터(outer)를 포함하여 다양한 형상의 스틸 강화재로 구성되며, 이와 같은 스틸 강화재 중 2가지의 스틸 강화재를 복합재로 대체하고자 한다. 이와 같은 스틸 강화재는 강화재 각각을 따로 제작하여 용접을 통해 결합되지만, 복합재 강화재는 패치(patch) 형태의 CFRP와 리브(rib) 구조의 GFRP를 활용하여 압축과 사출 공정을 통해 한번에 제작된다. CFRP는 B필러의 고강도부에 부착되어 측면 하중에 저항하도록 하였으며, GFRP 리브는 위상 최적화(Topology optimization) 기법을 통해 비틀림과 측면 하중을 저항하도록 설계하였다. 구조해석을 통해 기존 스틸 강화재와 비교 분석을 수행하였고, 경량화율을 산출하였다.

• 한국재료학회지
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• 제6권2호
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• pp.210-220
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• 1996

The purpose of this study is to develop the processing techniques of Fiber Reinforced Metal by Liquid Phase Diffusion Bonding method with SiC fiber as a reinforcing material and CP Ti(Commercial Pure) as a matrix. The microstructure and the distribution of elements in reaction and CP Ti(Commercial Pure) as a matrix. The microstructure and the distribution of elements is reaction zone among CP Ti/Ti-15wt%Cu-20wt%Ni(TCN20)/SiC long fiber were investigated by Optical Microscope, SEM/EDX, EPMA, X-ray and AES. The results obtained in this study are as follows. 1) When Ti matrix composite materials are fabricated under the bonding condition of 1273Kx1200sec, the SiC long fiber was the most suitable reinforcing material for Ti matrix composite materials. 2) With SiC long fiber under same condition, a TiC layer(1.0-1.6$\mu\textrm{m}$) was observed on the surface of SiC long fiber. 3) Liquid Phase Diffusion Bonding has shown the feasibility of production of Ti matrix composite materials.

• 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.

• 열처리공학회지
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• 제32권3호
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• pp.107-112
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• 2019

In order to investigate the effect of plastic deformation and annealing process parameters on strength and electrical conductivity of Cu-Fe alloys, Cu-10wt%Fe, Cu-15wt%Fe alloys were drawn up to ${\eta}=4$ and annealed in the temperature range of $300^{\circ}C$ to $700^{\circ}C$, followed by measurements of tensile strength and electric conductivity. As draw strain increases, tensile strength increases while electrical conductivity decreases. These observations result from reduction of dislocation density and decrease in Fe fiber spacing. Raising annealing temperature brought about decrease of tensile strength and increase of electrical conductivity up to $500^{\circ}C$, being followed by decreasing above $500^{\circ}C$. Such results are thought to be caused by decrease of dislocation density below $500^{\circ}C$ and rapid solubility increase of Fe in Cu above $500^{\circ}C$. For the purpose of obtaining both high strength and high conductivity, annealing process should be incorporated just prior to reaching to final draw strain. For Cu-10wt%Fe alloy, the tensile strength 706.9 MPa and the electrical conductivity 54.34%IACS were obtained through the processes of drawing up to ${\eta}=3$, annealing at $500^{\circ}C$ for 1 hour and additional drawing up to total strain of ${\eta}=4$.

• 멤브레인
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• 제32권6호
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• pp.456-464
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• 2022

본 실험에서는 무전해 도금을 통하여 Pd 및 Pd-Cu 분리막을 제조하여 수소 투과 성능을 분석하였다. 분리막의 지지체는 α-Al₂O₃ 세라믹 중공사를 사용하였다. Pd-Cu 분리막은 무전해 도금을 실시하였고 Pd-Cu 합금을 만들기 위하여 수소 분위기에서 500°C, 18 h 동안의 열처리 과정을 거쳤다. 그 후, Pd-Cu 분리막은 EDS (Energy Dispersive X-ray Spectroscopy), XRD (X-ray Diffraction) 분석을 통해 합금이 형성된 것을 확인하였다. Pd 및 Pd-Cu 도금층의 두께는 SEM (Scanning Electron Microscope) 분석을 통해 각각 약 3.21, 3.72 µm으로 측정되었다. 수소 투과 성능은 수소 단일 가스, 혼합가스(H₂, N₂)에서 350~450°C, 1~4 bar의 범위에서 수소 투과 실험을 진행하였다. 수소 단일 가스에서 Pd 및 Pd-Cu 분리막은 450°C, 4 bar에서 최대 54.42, 67.17 ml/cm²⋅min의 flux를 가지며, 혼합가스에서는 450°C, 4 bar의 조건일 때, 각각 1308, 453의 separation factor가 나오는 것을 확인하였다.