• 한국수소및신에너지학회논문집
• /
• 제24권5호
• /
• pp.367-372
• /
• 2013

Hydrogen storage as a metal hydride is the most promising alternative because of its relatively large hydrogen storage capacities near room temperature. TiMn2-based C14 Laves phases alloys are one of the promising hydrogen storage materials with easy activation, good hydriding-dehydriding kinetics, high hydrogen storage capacity and relatively low cost. In this work, multi-component, hyper-stoichiometric $Ti_{0.85}Zr_{0.13}(Fe_x-V)_{0.56}Mn_{1.47}Ni_{0.05}$ C14 Laves phase alloys were prepared by a vacuum induction melting for a hydrogen storage tank. Since pure vanadium (V) is quite expensive, the substitution of the V element in these alloys has been tried and some interesting results were achieved by replacing V by commercial ferrovanadium (FeV) raw material. In addition, the melt-spinning process, which was applied to the manufacturing of some of these alloys, could make the plateau slopes much flatter, which resulted in the increase of reversible hydrogen storage capacity. The improvement of sloping properties of melt-spun $Ti_{0.85}Zr_{0.13}(Fe_x-V)_{0.56}Mn_{1.47}Ni_{0.05}$ alloys was mainly attributed to the homogeneity of chemical composition.

• 한국약용작물학회지
• /
• 제18권2호
• /
• pp.74-78
• /
• 2010

This experiment was carried out to select suitable organic matter in To-jik nursery (self soil nursery) for complement To-jik nursery's defects that are deterioration of raw material by poor quality of seed ginseng and reduction of the quantity in seed ginseng production. Organic matter used were Yacto, rice bean, defatted rice bran, soybean cake and their mixture. As follows, bulk density in soil physical property by treating organic composts was the greatest in soybean cake and the next was followed by mix, Yacto, defatted rice bran, and rice bran treatment in order. Soil pore space ratio was totally the opposite; that was rice bran the first and followed by defatted rice bran, Yacto, mix and soybean cake treatment. The incidence rate of damping off by treating organic composts was 1.5% in both soybean cake and mix while the others was 1.0%. Emergence time was the same among treatment on April 16 and Emergence rate was the highest at 73% in Yacto. There was no significant differences among treatment in the growth of aboveground part but it was a little better in defatted rice bran treatment. In Yacto treatment, the growth of underground part, total root number per kan, rate of first grade ginseng seedling, and rate of usable ginseng seedling etc. were entirely higher but there was little differences. Using defatted rice bran was slightly lower in productivity compared to Yacto, but the possibility was high as a alternative for Yacto in a view of managing cost down.

• 한국재료학회지
• /
• 제28권1호
• /
• pp.6-11
• /
• 2018

There are various manufacturing processes for pure $SiO_2$ that is used as abrasives, chemicals, filters, and glasses, and in metallurgy and optical industries. In the optical fiber industry, to produce $SiO_2$ preform, $SiCl_4$ is utilized as a raw material. However, the combustion reaction of $SiCl_4$ has caused critical environmental issues, such as ozone deficiency by chlorine compounds, the greenhouse effect by carbon dioxide and corrosive gas such as hydrochloric acid. Thus, finding an alternative source that does not have those environmental issues is important for the future. Octamethylcyclotetrasiloxane (OMCTS or D4) as a chlorine free source is recently promising candidate for the $SiO_2$ preform formation. In this study, we first conducted a vaporizer design to vaporize the OMCTS. The vaporizer for the OMCTS vaporization was produced on the basis of the results of the vaporizer design. The size of the primary particle of the $SiO_2$ formed by OMCTS was less than 100 nm. X-ray diffraction patterns of the $SiO_2$ indicated an amorphous phase. Fourier-transform infrared spectroscopy analysis revealed the Si-O-Si bond without the -OH group.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
• /
• pp.373-379
• /
• 2006

Fiber characteristics and fiber distribution of thermomechanical pulp(TMP), bisulfite chemithermomechanical pulp(bisulfite CTMP), neutral sulfite chemithermomechanical pulp(neutral sulfite CTMP) from kenaf(Hibiscus cannabinus L., Malvaceae) cultivar Tainug-2 cultivated in the reclaimed land of Korea were examined to use effectively nonwood fibers as an alternative raw material sources for papermaking. Yields of TMP and CTMP from kenaf were lower than those of TMP from hardwoods and CTMP from softwoods and hardwoods. Bark fibers of kenaf cultivar Tainung-2 ranged 2.04 to 2.30 mm long and $18.7{\sim}19.7{\mu}m$ width. Core fibers averaged 0.63 to 0.80 mm long and $29.5{\sim}31.4{\mu}m$ wide. Coarseness of bark fiber was higher than that of core fiber, and fiber from TMP were higher than those from both bisulfite CTMP and neutral sulfite CTMP. Curl indexes of bark fibers were higher than those of core fibers. However curl indexes were not significantly affected by the pulping conditions. Short fiber distributions were higher in core fibers from TMP and CTMP and long fiber distributions were higher in bark fibers. There was no significant difference in fiber distribution of whole and core fibers obtained from TMP and CTMP, Fibers from neutral sulfite CTMP, however, exhibited a little higher long fiber distribution. Distinct difference in anatomical characteristics was found between core and bast fibers of kenaf plant. Parenchyma cell, pith parenchyma cell and vessel were observed in core fibers and bast fiber in bast sections.

• 한국시뮬레이션학회논문지
• /
• 제20권2호
• /
• pp.49-57
• /
• 2011

치열한 경쟁과 원자재 가격 급등은 시행착오를 최소화 하면서 제철소를 최적으로 설계하여 운영할 것을 한층 더 강력하게 요구하고 있다. 컴퓨터 시뮬레이션은 이 요구에 부합되는 방법론을 제공할 수 있다. 본 논문의 목적은 제강 연주 공장의 설계와 운영을 지원하기 위한 시뮬레이터를 제안하는 것이다. 본 연구에서 제안하는 시뮬레이터는 유지보수와 확장에 용이하도록 널리 알려진 Arena로 개발되었으며 사용의 편의성을 위하여 엑셀 기반으로 입출력 인터페이스를 설계하였다. 또한 운반 대차와 천정 크레인으로 구성되는 복잡한 운반 모듈을 포함하여 모델의 정확도를 높였다. 시뮬레이터는 생산량 분석과 물류 분석을 통하여 제강 연주 공장 설계안의 적정성을 평가하는데 유용하게 사용될 수 있다. 그리고 다양한 상황별로 최적의 제품 조합을 도출하는데 적용될 수 있으며, 공정별 설비별로 작업을 배정하는 조업 운영 패턴을 평가하고 정확도를 향상시키는 도구로써 활용이 가능하다.

• 전기화학회지
• /
• 제3권3호
• /
• pp.173-177
• /
• 2000

리튬 이차 전지의 성능은 부극으로 쓰이는 탄소재료의 표면의 미세 구조에 크게 의존한다. 본 연구에서는 이러한 표면 구조의 개질을 위해 유동상 화학증착법을 도입하여 금속 및 금속 산화물을 탄소재료 표면에 코팅하여 그 성능을 전기 화학적으로 평가하였다. 주석산화물을 코팅한 탄소 전극은 원래의 탄소 전극에 비해 용량의 상승을 나타내었으나 사이클이 진행됨에 따라 주석산화물이 코팅된 전지의 용량은 심각한 부피 변화에 의해 저하되어 사이클 수명이 감소되었다. 그러나, 부피 변화를 완화시켜주는 비활성 매트릭스 역할을 하는 구리를 주석 산화물 위에 코팅함으로 인해 부피 변화에 의한 용량 저하를 감소시킬 수 있었다.

• Journal of the Korean Wood Science and Technology
• /
• 제48권1호
• /
• pp.32-40
• /
• 2020

While the utilization of wood as a raw material in related industries has been increasing with the population increasing, the availability of wood from natural forests has continued to decline. An alternative to this situation is the manufacture of particleboard from non-wood lignocellulose materials through the modification of sandwich particleboard (SPb) using bamboo strands as reinforcement. In this study, strandsof belangke bamboo (Gigantochloa pruriens W) and tali bamboo (Gigantochloa apus) were utilized. The non-wood particles included sugar palm fibers, cornstalk, and sugarcane bagasse. The board was made in a three-layer composition of the face, back, and core in a ratio of 1: 2: 1. The binder used was 8% isocyanate resin. The sheet was pressed at a temperature of 160℃ for 5 min under a pressure of 3.0 N/㎟. Testing included physical and mechanical properties based on the JIS A 5908 (2003) standard, while acoustic testing was based on ISO 11654 (1997) standards. The results showed that using bamboo strands as reinforcement has an effect on the mechanical and physical properties of SPb. Almost all the types of boards met the JIS A 5908 (2003) standards, with the exception of thickness swelling (TS) and internal bond (IB) parameters. Based on the thickness swelling parameter, the C-type board exhibited the best properties. Overall, the B-type board thatused a belangke bamboo strand for the surface and sugarcane bagasse as the core underwent the best treatment. Based on the acoustical parameter, boards using a tali bamboo strand for the surface and sugar palm fiber as the core (E-type board) exhibited good sound absorption properties.

• 산업식품공학
• /
• 제13권2호
• /
• pp.130-137
• /
• 2009

This study evaluated the potential of utilizing the osmotic solution from dried mango processing as alternative raw material for mango wine making. Fermentation was carried out using two kinds of yeast strains Saccharomyces bayanus, Lalvin EC-1118 and Saccharomyces cerevisiae, Lalvin D-47 at 20$^{\circ}C$ for 28 days. Physicochemical analysis during fermentation was performed for each treatment and the resulting wine samples were analyzed for color, volatiles and sensory properties. Results of physicochemical analysis between the two fermenting samples as well as the wine samples show almost similar results regardless of the yeast strains. Wine color of sample wines after storage were not significantly different at p<0.05 and when compared with a commercial mango wine. From the volatile analysis, esters and alcohols constituted majority of the compounds. Production of several esters, alcohols, acids and terpenes were affected by yeast strain used in fermentation. Results of sensory analysis showed that wines fermented by S. bayanus EC-1118 strain was more acceptable although sensory scores between the treatments and the reference wine showed significant differences in all the attributes evaluated, except for bitterness. The utilization of osmotic solution from dried mango process could produce similar properties with existing commercial mango wines although there is still need for further work on the improvement of some sensory attributes of the mango wines.

• 융합정보논문지
• /
• 제11권11호
• /
• pp.239-247
• /
• 2021

본 논문은 대체식품 및 화장품 원료로 사용되는 미강을 발효를 통해 기능성과 경쟁력을 증가시키는 것을 목표로 하였다. 미강 추출물과 누룩에서 분리된 Saccharomycopsis fibuligera A8로 발효된 미강 추출물을 이용해 세포독성과 항염효과를 확인하였다. 세포 독성의 경우 미강 추출물의 경우 100 ㎍/mL에서 세포독성을 보였으나 발효 미강 추출물의 경우에는 세포독성을 보이지 않았다. 한편 nitric oxide, IL-6, TNF-α, IL-1β와 같은 염증 지표를 통해 항염효과를 확인한 결과, 미강 추출물은 nitric oxide, TNF-α만 100 ㎍/mL이상의 농도에서 항염효과를 보였다. 발효 미강 추출물의 경우에는 각각 25 ㎍/mL, 25 ㎍/mL, 50 ㎍/mL, 50 ㎍/mL의 농도에서 항염효과를 보여 더 낮은 농도로 항염효과를 나타내는 것을 확인하였다. 한편 S. fibuligera A8 사균체의 세포 독성 및 항염 효과를 실험한 결과 발효 산물에서 사균체 역시 유효하게 작용하는 것을 알 수 있었다.

• 한국융합학회논문지
• /
• 제12권11호
• /
• pp.403-410
• /
• 2021

본 논문은 대체식품 및 화장품 원료로 사용되는 미강을 발효를 통해 기능성과 경쟁력을 증가시키는 것을 목표로 하였다. 5종류의 누룩에서 분리한 Saccharomycopsis fibuligera 50종의 균주 중 효소 활성이 우수한 6균주와 표준균주를 이용한 발효미강물의 𝛼-amylase, CMCase, 𝛽-glucosidase, protease 등의 효소 활성을 통해 비교한 결과, A8균이 KCTC 7806 균주에 비하여 13.7%, 21.1%, 50.3%, 10.0%의 우수한 효소 활성을 보였다. 발효의 결과지표로서 ABTS, DPPH 검사를 시행한 결과, A8으로 발효한 미강이 KCTC 7806 균주로 발효한 미강에 비하여 1.12배, 1.28배의 항산화능이 있음을 확인하였다. 본 논문으로, S. fibuligera 표준균주인 KCTC 7806 보다 우수한 S. fibuligera A8 균주를 확인할 수 있었다. 또한, 선행연구과제의 항염활성 및 항독성 결과와 더불어 우수한 효소 활성과 항산화능 결과를 통해 S. fibuligera A8 균주를 통한 미강 발효물이 대체식품 및 화장품 원료로서의 기능성과 가격 경쟁력을 증가시킬 수 있음을 확인하였다.