• Natural Product Sciences
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• 제22권3호
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• pp.201-208
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• 2016

Here in this study, we investigated the lifespan-extending effect and underlying mechanism of methanolic extract of Moringa olelifa leaves (MML) using Caenorhabditis elegans (C. elegans) model system. To define the longevity properties of MML we conducted lifespan assay and MML showed significant increase in lifespan under normal culture condition. In addition, MML elevated stress tolerance of C. elegans to endure against thermal, oxidative and osmotic stress conditions. Our data also revealed that increased activities of antioxidant enzymes and expressions of stress resistance proteins were attributed to MML-mediated enhanced stress resistance. We further investigated the involvement of MML on the aging-related factors such as growth, food intake, fertility, and motility. Interestingly, MML significantly reduced growth and egg-laying, suggesting these factors were closely linked with MML-mediated longevity. We also observed the movement of aged worms to estimate the effects of MML on the health span. Herein, MML efficiently elevated motility of aged worms, indicating MML may affect health span as well as lifespan. Our genetic analysis using knockout mutants showed that lifespan-extension activity of MML was interconnected with several genes such as skn-1, sir-2.1, daf-2, age-1 and daf-16. Based on these results, we could conclude that MML prolongs the lifespan of worms via activation of SKN-1 and SIR-2.1 and inhibition of insulin/IGF pathway, followed by DAF-16 activation.

• Journal of Welding and Joining
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• 제31권5호
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• pp.54-58
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• 2013

Joint properties of vehicle ECU (Electric Control Unit) module which was manufactured by using Sn-Cu-Cr-Ca alloy were investigated. A new solder which has a middle melting temperature about $231^{\circ}C$ was fabricated as the type of 300um solder ball and paste type. The prototype modules were made by reflow process and measured spreadability, wettability shear strength and estimated interface reaction. The spreadability of the alloy was about 84% from the measurement of contact angle of the solder ball and the wetting force was measured 2mN. The average shear strength of the module which was manufactured by using the solder paste, was 1.9 $kg/mm^2$. Also, the thickness of IMC(intermetallic compound) was evaluated with various aging temperature and time in order to understand Cr effect on Sn-0.7Cu solder. $Cu_6Sn_5$ IMC was formed between Cu pad and the solder alloy and the average thickness of the $Cu_6Sn_5$ IMC was measured about 4um and it was about 50% of thickness of $Cu_6Sn_5$ IMC in Sn-0.7Cu. It is expected to have a positive effect on reliability of the solder joint.

• 열처리공학회지
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• 제5권2호
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• pp.103-110
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• 1992

This study is aimed to investigate the effect of various thermomechanical treatments($T_6$, $T_8$ and ITMT) on the microstructure and mechanical properties of an Al-Cu-Li-Ag-Mg-Zr alloy (Weldalite 049) which has been known to strong natural aging response, good weldablity and high strength in $T_6$ sand $T_8$ temper. This experiment was performed by means of differential scaning calorimetry, tensile test, optical and transmission electron microscopy. The tensile strength in the peak aged condition shows 620, 650 MPa in $T_6$ and $T_8$(40% cold work), respectively. Also, The tensile strength is increased with cold working in $T_8$ but decreased at 60% cold working. However, the tensile strength of the intermediate thermomechanical treated speciman(ITMT) is lower than that of $T_6$ temper about 20% but the elongation is higher than two times. It might be predicted that the ITMT is effective processing to improve the toughness of this alloy. In $T_6$, $T_8$ and ITMT, the major strengthening phase is $T_1(Al_2CuLi)$ phases. and the fine $T_1$ phase which are homogeneously precipited in matrix was observed much more in $T_8$ than $T_6$ and ITMT.

• 보존과학연구
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• 통권33호
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• pp.19-32
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• 2012

천연재료를 사용하는 지류유물의 손상은 재질적 특성상 어떤 한 가지 요인에 의한 훼손보다는 물리적, 화학적, 생물학적 복합요인에 의한 손상 가능성이 높다. 문화재보존과학센터는 2009년 12월 현충사 관리소로 부터 이 충무공관련 유물의 상태조사 및 보존처리를 의뢰받아 조사한 결과 위와 같은 다양한 훼손요인을 확인할 수 있었다. 조사결과를 토대로 각 유물의 손상정도를 파악한 후 적절한 보존방안을 수립하고, 2010년부터 약 2년에 걸쳐 보존처리를 실시하였다. 이 충무공 관련 유물 중 고문서, 전적류 등과 같이 형태가 다른 고문헌에 대한 손상유형과 보존처리 내용을 소개함으로서 보존처리방법을 선택하는 하나의 예시를 제안하고자 하였다. 지류유물에 대한 보존처리는 유물의 노화주기를 연장시키고 2차 손상을 방지하지만, 유물의 노화를 완전히 멈추게 하는 과정이 아니므로 유물에 대한 정기적 점검이 필요할 것이다.

• 멤브레인
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• 제22권5호
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• pp.342-351
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• 2012

본 연구에서는 PTMSP[poly(1-trimethylsilyl-1-propyne)]의 기체투과에 대한 선택도와 열적 안정성, 시간에 따른 노화현상으로 인한 투과특성의 감소를 개선하기 위해서 PTMSP/PDMS[poly(dimethylsioxane)] graft copolymer에 zeolite를 삽입하여 PTMSP/PDMS-NaY zeolite 복합막과 PTMSP/PDMS-NaA zeolite 복합막을 제조하였다. 물리 화학적 특성을 FT-IR, $^1H$-NMR, TGA, SEM, GPC을 사용하여 조사하였고, $H_2$와 $N_2$ 기체에 대한 투과도와 선택도 성질을 고찰하였다. PTMSP/PDMS-NaY zeolite 복합막과 PTMSP/PDMS-NaA zeolite 복합막 $H_2$와 $N_2$ 투과도는 PTMSP/PDMS graft copolymer 단일막보다 증가하였고, zeolite 함량이 증가함에 따라 증가하였다. 반면에 선택도($H_2/N_2$)는 zeolite 함량이 증가함에 따라 감소하였다. PTMSP/PDMS-NaA zeolite 복합막은 PTMSP/PDMS-NaY zeolite 복합막보다 높은 투과도와 선택도를 보였다.

• Journal of Microbiology and Biotechnology
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• 제28권6호
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• pp.883-892
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• 2018

Probiotics, including Enterococcus faecium, confer a health benefit on the host. An Enterococcus strain was isolated from healthy chicken cecum, identified as E. faecium by 16S rDNA gene sequence analysis, and designated as E. faecium L11. To evaluate the potential of E. faecium L11 as a probiotic, the gastrointestinal tolerance, immunomodulatory activity, and lifespan extension properties of the strain were assayed. E. faecium L11 showed >66% and >62% survival in artificial gastric juice (0.3% pepsin, pH 2.5) and simulated small intestinal juice (0.5% bile salt and 0.1% pancreatin), respectively. Heat-killed E. faecium L11 significantly (p < 0.05) increased immune cell proliferation compared with controls, and stimulated the production of cytokines (IL-6 and $TNF-{\alpha}$) by activated macrophages obtained from ICR mice. In addition, E. faecium L11 showed a protective effect against Salmonella Typhimurium infection in Caenorhabditis elegans. In addition, feeding E. faecium L11 significantly (p < 0.05) extended the lifespan of C. elegans compared with the control. Furthermore, genes related to aging and host defense were upregulated in E. faecium L11-fed worms. In conclusion, E. faecium L11, which prolongs the lifespan of C. elegans, may be a potent probiotic supplement for livestock.

• 한국식품과학회지
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• 제22권1호
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• pp.38-43
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• 1990

녹두전분의 농도(5-8%, 건량기준)와 가열온도$(80-95^{\circ}C$)가 전분의 리올로지에 미치는 영향을 조사하였다. 녹두전분은 농도에 관계없이 아밀로그래프의 최고점도를 보이지 않았고 가열 중 점도는 계속 증가하였다. 전분호화액은 항복응력을 가진 의가소성 유체의 성질을 보였고, 점조도지수는 농도와 가열온도가 증가할수록 증가하였으나, 유동지수는 반대로 감소하였다. 전분 겔을 $4^{\circ}C$에 저장하는 동안 겔의 수축정도는 농도와 가열온도가 증가할수록 감소하였다. 아밀로그래프를 이용하여 $95^{\circ}C$에서 15분간 호화시켜 만든 농도 7과 8%의 겔의 초기경도는 6% 겔보다 2배 이상 높았으나, $4^{\circ}C$에서의 노화속도는 농도와 가열온도에 크게 영향을 받지 않았다.

• 동아시아식생활학회지
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• 제24권3호
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• pp.400-406
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• 2014

본 연구에서는 아피오스로부터 전분을 추출하여 epichlorohydrin으로 가교결합을 시킨 후 가교결합 아피오스 전분의 이화학적 특성을 분석하였다. 가교결합 아피오스 전분은 치환도가 증가함에 따라 몰가교화도가 0.1225에서 3.5124로 비례적으로 증가하였으며, FT-IR을 측정한 결과, CLAP-2%는 에테르 결합으로 인하여 $1,646cm^{-1}$과 $2,930cm^{-1}$에서 피크의 강도가 강해져 가교결합 반응이 이루어졌음을 확인할 수 있었다. 천연 아피오스 전분의 X-선 회절도는 $2{\theta}$=15.1, 17.1, 17.9, $23.2^{\circ}$에서 피크가 나타나는 전형적인 A형 전분 형태를 나타내었으며, 가교결합 아피오스 전분은 가교화에 의해 회절도와 상대결정화도에 큰 변화를 보이지 않아 무결정 영역에서 가교결합 반응이 일어난 것으로 추정되었다. 아피오스 전분 입자를 SEM으로 관찰한 결과, 전분 입자는 구형 또는 타원형 모양을 나타내었으며, 가교결합 아피오스 전분은 천연 아피오스 전분과 비교하였을 때 전체적인 형태에는 변화가 없는 것이 관찰되었다. 색도는 가교결합이 진행되면서 명도와 청색도가 변화하였으며, 청가는 천연 아피오스 전분과 가교결합 아피오스 전분 사이에 유의적인 차이가 나타나지 않았다.

• 대한화학회지
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• 제31권1호
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• pp.110-117
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• 1987

선형저밀도폴리에틸렌(LLDPE)의 제조를 위해 여러가지 티탄알콕시드-알킬알루미늄 화합물을 촉매로 하여 에틸렌과 1-부텐을 슬러리 상태로 공중합하였다. 이때 촉매성분의 종류 및 농도, 숙성시간, 중합시간과 중합온도 등이 촉매활성과 공중합체 조성에 미치는 영향을 연구하였다. 그리고 공중합체의 성질과 1-부텐 함량과의 관계를 조사하였다. 그 결과 티탄사노르말부톡시드-염화디에틸알류미늄의 촉매를 사용하였을 때 가장 큰 촉매활성, 보다 많은 1-부텐 함량 및 가장 작은 가용성 부분의 LLDPE를 얻을 수 있었다. 얻은 공중합체의 밀도, 유리전이온도, 녹는점 및 녹음열 등은 1-부텐의 함량이 증가함에 따라 감소하였다.

• 한국조리학회지
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• 제4권
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• pp.249-269
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• 1998

What satisfies the desire of human beings about taste most easily is sweet taste, and it has seemed that the pronoun of sweet taste is sugar. Sugar is used in confectionery and bread-making essentially, and it has influence on the structure and touch of baked confectionery. In addition, if we soften the and apply heat, coloring is made. Thus, it colors good. It doesn't have a sweet taste, but it has the effect to emit fragrance variously, balance and soften the product. The kinds of sugar are very diverse, and it is sugar to be referred to as white sugar is used most frequently. In this study, this researcher examined the classification of physicochemical property and melting point etc. of sugar in confectionery and bread-making through theoretical study, about the simple classification of sugar. In addition, this researcher approached about the role of sugar in confectionery and bread-making and about the influence to have when it is more or less than proper quantity, centering around function. As the result, this researcher extracted the importance of sugar in confectionery and bread-making. It means that the increase of 5% of sugar quantity decreases the absorption quantity of moisture by 1% in bread-making and that the excess of 8% of sugar slow the action of yeast in straight method. Besides, there are the properties such as absorptive property, permeability, storage nature, aging prevention of starch, oxidation restraint of oils and fats, the gelation action of pectin, the fermentation acceleration of yeast, and the emulsification-maintaining-nautre and antiseptics effect of fat-soluble material. And in confectionery, sugar makes fragrance and peel color, increases the storage nature with moisture maintenance and has the softening effect. So, it is considered that the attitude to study and make efforts continuously on the basis of the role of sugar will have to be unfolded in confectionery and bread-making.