• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.255-260
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• 1997

Glucomannan was isolated from konjac (Amorphophallus konjac) flour by precipitating in aqueous alcohol solution. Konjac glucomannan films were prepared at various concentrations up to 1.0% (w/v) in aqueous glycerol solutions. Tensile strength (TS), percent elongation (E), water vapor permeability (WVP) as the barrier property and the solubility of the films were varied with glucomannan concentrations, glycerol contents and storage humidities. TS was decreased as the glucomannan concentration in the film and relative humidity for storage increased, and E was vice versa. WVP showed better barrier properties compared with other polysaccharides films. Glycerol contents in the film significantly affccted TS and E, but did not affect WVP. The glucomannan films were completely dissolved in the water by 150 min stirring at room temperature.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.53-53
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• 2011

Poly(lactic acid)(이하 PLA라 칭함)는 1970-80년대의 초기 연구에서는 높은 제조비용과 희귀성에 의해 봉합사와 약물전달시스템으로 용도가 제한적이었으나 1980년대를 거쳐 1990년 이후 농업의 혁신적인 변화를 거쳐 옥수수의 다양한 측면의 이용의 하나로서 6-7년 전부터 양산화에 성공하여, 의류, 필름 및 플라스틱의 여러 가지 분야에서 적용가능성을 모색하고 있다. PLA의 장점은 석유가 아닌 천연 원료에서 얻을 수 있으며, 기존의 합성섬유와는 달리 일정한 조건하에서 미생물 등에 의해 물과 이산화탄소로 90% 이상 분해되는 친환경적인 소재이다. 합성섬유에서 의류용으로 대부분 사용되는 폴리에스테르(이하 PET라 칭함)와 유사한 물성을 가지고 있는 PLA섬유는 PET섬유와 유사한 분산염료로 염색할 수 있다. 따라서 PLA섬유는 분산염료에 의한 염색법을 중심으로 연구되어지고 있으나, PET 섬유의 융점이 $254^{\circ}C$부근인 반면, PLA섬유는 $160-170^{\circ}C$부근이다. 이로 인해 PLA를 섬유로 용도전개에 있어서 약점으로 작용하고 있다. 그러나 PLA섬유는 특유의 경량감과 새로운 촉감 등의 많은 장점을 지니고 있어 여러 가지 용도전개가 되어지고 있다. 초음파는 사람이 들을 수 없는, 사람마다 한계값은 다르지만, 주파수 약 25kHz이상의 음파를 말하며, 주파수가 높고 파장이 짧기 때문에 강한 진동을 수반한다. 초음파의 이용 원리는 Cavitation이라는 현상으로 생성된 기포가 터지면서 강력한 에너지를 방출한다. 이것은 강력하여 사방으로 퍼져 물질표면이나 내부에 영향을 미친다. 섬유에서는 표면에 뭍은 불순물을 제거하는 세정 등에 응용되고 있으며, 염색분야에서도 다양하게 연구되어지고 있다. 본 연구에서는 초음파에 의한 PLA섬유의 염색성을 조사하였다. PLA섬유를 정련하여 초음파작용의 유무에 따라 염색하여 그 결과를 고찰하였다. 초음파 작용에 따른 분산염료의 표면 색변화는 없었으며, 섬유 표면 색 농도의 차이는 초음파 작용에 의하여 저온에서는 차이가 나타나지만, 고온인 $80^{\circ}C$에서는 오히려 낮아졌다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.608-616
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• 1996

To propose the use of skipjack processing by-product(SPB) as a food material, the optimal condition for the production of the SPB hydrolysate through enzyme treatment was obtained using RSM(Response Surface Methodology). Among eight pretenses test, Pretense $P^{TM}$ was screened primarily on the aspect of production cost and taste of the product. The extent of autolysis accompanied by endogenous enzyme in the SPB was almost negligible as compared with that of Protense $P^{TM}$ treatment. The derived model equation was within the satisfiable range as indicated by coefficient of $determination(R^2=0.9460)$ and lack of fit(p>0.1) values. From the results of RSM and ridge analysis, the conditions favoring the higllest degree of hydrolysis were: PH 7.2, $51^{\circ}C,$ reaction time of 3.94 hr, substrate concentration of 33.3%, and enzym $e_strate ratio of 0.48%.48%.8%.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.53-53
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• 2012

Poly(lactic acid)(이하 PLA라 칭함)는 초기 연구에서는 제조비용과 희귀성으로 봉합사 등의 의료용 등의 용도가 제한적이었으나 1980년대의 유전공학의 발전과 이를 바탕으로 1990년 이후 농업의 혁신적인 변화를 거쳐 옥수수의 여러 측면의 이용 중의 하나로서 2000년 초에 양산화에 성공하여, 의류, 필름 및 플라스틱의 다양한 분야에서 적용되고 있다. PLA의 장점은 석유가 아닌 천연 원료에서 얻을 수 있으며, 기존의 합성섬유와는 달리 일정한 조건하에서 미생물 등에 의해 물과 이산화탄소로 분해되는 친환경적인 소재이다. 합성섬유 중에서 의류용의 대부분 차지하는 폴리에스테르(이하 PET라 칭함)와 유사한 물성을 가지고 있는 PLA섬유는 PET섬유와 유사한 분산염료로 염색할 수 있다. 따라서 PLA섬유는 분산염료에 의한 염색법을 중심으로 연구되어지고 있으나, PET 섬유의 융점이 $254^{\circ}C$부근인 반면, PLA섬유는 $160-170^{\circ}C$ 부근이다. 이로 인해 PLA를 섬유로 용도전개에 있어서 약점으로 작용하고 있다. 그러나 PLA섬유는 특유의 경량감과 새로운 촉감 등의 많은 장점을 지니고 있어 여러 가지 용도전개가 되어지고 있다. 배트염료는 그 자체로서는 불용성으로 섬유와 친화성이 낮지만, 알칼리성 환원욕에서 셀룰로오스 섬유 등에 친화성이 있다. 화학구조적으로 안트라키논, 인디고계가 주류를 이루고 있으며, 색상적으로는 화학구조의 제약으로 선명도가 약깐 낮은 중간색 계통이 대부분이지만, 견뢰도 면에서는 다른 염료에서는 얻을 수 없는 높은 견뢰도를 가지는 것이 배트염료가 지니는 장점중의 하나이다. 셀룰로오스계 섬유에 주로 이용되는 배트염료를 나일론과 폴리에스테르 중심으로 합성섬유에 적용하는 연구 및 실용화가 되어지고 있다. 본 연구에서는 Indigo Blue 1을 중심으로 염색된 PLA섬유의 반복 세탁에 의한 염색물의 변 퇴색성을 조사하였다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.445-448
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• 2004

Aging is divided into intrinsic aging and photo-aging. Intrinsic aging is naturally occurred as the time passed and photo-aging is induced by the UV radiation of skin. The main reason of aging is the free radicals and the degeneration of the cellular materials by free radicals. In this paper, we checked the anti-aging effects of Mallotus japonicus bark extracts. It has the ability to scavenge free radicals and the SOD like activity. Also, it reduced the cell damage by hydrogen peroxide treatment. Mallotus japonicus bark extracts showed the excellent activity on inhibiting the UV induced cell damage and DNA damage. In conclusion, Mallotus japonicus bark extracts can be used as active ingredients for anti-aging cosmetics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.33 no.1 s.60
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• pp.41-45
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• 2007

Recently plant extracts have obtained increased attention because of their health-related beneficial aspects. In this study, we evaluated anti-oxidation, whitening and anti-wrinkle of four different extracts obtained from Rubus coreanus (ethanol extracts of unripe, ripe fruits, leaves/stems, and roots). The ethanol extract of unripe fruits of Rubus coreanus generally showed stronger whitening and the anti-wrinkle activities than other extracts of Rubus coreanus. As a results, we knew that the ethanol extract of unripe Rubus coreanus fruit had mote possibility as a whitening and anti-wrinkle ingredient for skin care products.

• Journal of Ginseng Research
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• v.23 no.2 s.54
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• pp.67-73
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• 1999

This study carried out to scanning and select the antimicrobial pharmaceuticals which were suppress the rottening of fresh ginseng. We are isolated 20 kinds of microorganisms from rotten ginseng. In these of the microorganisms, five bacteria, fresh ginseng root-rottening, are identified to Pseudomonas putida, Pseudomonas putida biotype A, Bacillus spp, Enterobacter cloacae, and Klebsiella pneumoniae. Particularly. Bacillus spp was rapidly rotted the ginseng root, compared with the others. The antimicrobial activity were tested with 19 kinds of water extracts, and 34 kinds of essential oils. The water extract of Terminaliae Fructus, and Schiandra chinensis are strongly inhibited the growth of bacteria causing the ginseng root-rottening. And 5 kind of essential oils are inhibited bacteria. It was regarded that the water extract of Terminaliae Fructus has weekly water insoluble and polar antimicrobial components.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.4
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• pp.154-159
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• 2001

(Li,Al)$MnO_2(OH)_2$:Co compound was synthesized by hydrothermal method. $MnO_2$, LiOH.$H_2$O, $Co_3O_4$ and $Al(OH)_3$ were used as starting materials and the optimum conditions for synthesis of monolithic (Li,Al)$MnO_2(OH)_2$:Co compound were as follows : reaction temperature; $200^{\circ}C$, reaction time; 3 days, hydrothermal solvent; 3M-KOH solution, reaction apparatus; seesaw type, atomic ratio of Li:Al:Mn;Co = 1:2.1:2.5~2:0.5~1. Monolithic(Li,Al)$MnO_2(HO)_2$:Co compound synthesized in this work had a god crystallinity and excellent color forming effect as a blue pigment compatible with natural mineral. The particles of the synthesized (Li,Al)$MnO_2(OH)_2$:Co compound have hexagonal plate shape with the size of 0.5~1 $\mu\textrm{m}$.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1064-1067
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• 2012

Recently, there is a growing interest in vegetable oils, cheap and abundant renewable natural resources. Vegetable oils can be used as raw materials for ecofriendly biodegradable polymer materials. In this study, poly(${\beta}$-amino esters) were synthesized by polymerization reaction of acrylated epoxidized soybean oil (AESO) and 2-aminoethanol. Various polymer films were prepared by changing the molar ratio of AESO to 2-aminoethanol. The formation of C-N bonds in poly(${\beta}$-amino ester) was confirmed using FT-IR. Gel contents higher than 98% confirmed the synthesis of crosslinked polymer networks. Tensile strengths and elongation at breaks of polymer films ranged from 0.3 to 1.3 MPa and 32 to 55%, respectively. Polymer films degraded 2 to 7% of the initial weight in 35 days in phosphate buffer solution (pH 7.2) containing lipase enzyme.

• Journal of the Korean Ceramic Society
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• v.18 no.1
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• pp.3-12
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• 1981

A glass-ceramics based on blast-furnace slag, with some additives to the theoretical composition in order to control properties of mother glass and the heat treatment conditions, has been investigated. The raw materials in this study were blast-furnace slag, serpentine, feldspar and quartz as mother glass ingredients. Titanium dioxide and chromite were used as the nucleating agents. Batch compositions of the prepared glasses and ceraming conditions were found by trial and error method. The optimum conditions were confirmed by analyzing several measured physical properties such as density change during heat treatment, microhardness of slag-ceramics prepared, viscosity change of glass at heat treatment temperatures, nucleation density change, dilatometric properties, differential thermal analysis, identification of the grown crystal and crystal sizes. The batch composition feasible to prepare slag-ceramics was 40% of blast-furnace slag, 25% of serpentine, 18% of feldspar and 17% of silica sand. Three percent titanium dioxide and 1% chromite of the mother glass were added as nucleating agents. The ceraming conditions under which the slag-ceramics having considerably good properties can be developed found as: "The glass was heated at 75$0^{\circ}C$ for 2 hours for nucleation, and the temperature was raised up to 1, 00$0^{\circ}C$ with a rate of 0.75$^{\circ}C$/min for crystal growth.owth.