• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.223-224
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• 2007

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• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.458-461
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• 2011

수산화마그네슘을 첨가한 저밀도 폴리에틸렌-에틸렌 비닐 아세테이트 복합체의 연소성을 시험하였다. 저밀도 폴리에틸렌-에틸렌 비닐 아세테이트에 수산화마그네슘을 40~80wt% 첨가하여 용융 혼합하고 성형 후 콘칼로리미터(ISO 5660-1)를 이용하여 연소성을 시험하였다. 수산화마그네슘을 첨가한 시편은 첨가하지 않은 시험편에 비하여 그의 플래시오버 가능성이 감소하였다. 수산화마그네슘을 첨가한 시험편은 첨가하지 않은 시험편에 비해 낮은 총열방출량과 낮은 CO 발생량을 나타내었고, 수산화마그네슘 함량이 증가할수록 총연기발생량과 비소화면적이 감소하였다.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.203-206
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• 2001

산업용 섬유로서 그 사용 범위가 다양해질 것으로 예상되는 고강도, 고탄성률 폴리비닐알코올(PVA) 섬유를 얻기 위해서는 먼저 분지 구조가 없는 고분자량의 PVA의 합성이 필요하다. 그러나 비닐아세테이트와 같은 비공역형 단량체는 성장종 라디칼종의 활성이 매우 커서 성장반응 속도와 정지반응 속도가 매우 빠르므로 연쇄 이동반응이 빈번하게 일어나 고분자량의 중합체를 얻기 힘들고 또 분지구조를 갖게된다. (중략)

• Korean Journal of Food Science and Technology
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• v.37 no.3
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• pp.479-483
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• 2005

Antioxidative and protective effects of Ulmus davidiana var. japonica against oxidative damages induced by glutamate in PC 12 cells were investigated. Inhibitory activity against $FeSO_{4}-H_{2}O_{2}$-induced oxidative stress and DPPH radical-scavenging activity were detected in ethyl acetate and butanol fractions of ethanol extracts from stems and roots. Ethyl acetate and butanol fractions of ethanol extracts from roots significantly inhibited glutamate-induced cytotoxicity and reactive oxygen species in PC 12 cells. These results demonstrate ethyl acetate and butanol fractions of ethanol extracts of U. davidiana var. japonica have potent protective effect against glutamate-induced oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1601-1605
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• 2004

To develop the functional food, methanol extracts of dried plantain (Plantago asiatica L.) was fractionated in hexane, chloroform, ethyl acetate, butanol and aqueous fraction. DPPH radical scavenging effect, reducing power, nitrite scavenging effect and antimicrobial activities of these fractions were investigated. Ethyl acetate fraction among these fractions showed the highest effect of all experiments. Ethyl acetate fraction showed about 60% scavenging effect on the DPPH radicals at 400 $\mu$g/5 mL. Nitrite scavenging effect of ethyl acetate and butanol fraction was more than 70~80% at concentration above of 500 $\mu$g. Among various solvent fractions from methanol extracts of plantain, ethyl acetate fraction showed the highest inhibitory effect on the microorganism such as Staphylococcus aureus, Bacillus cereus and Vibrio parahaemolyticus at 5 mg/disc.

• Resources Recycling
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• v.13 no.6
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• pp.43-48
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• 2004

For the separation of neodymium from NdFeB permanent magnet scrap, the scrap was roasted for oxidizing, and leached with acetic acid followed by fractional crystallization for selective separation. From the analysis results of the leached solution, the optimum condition for the recovery of neodymium was found that leaching temperature, leaching time and pulp density are 80$^{\circ}C$, 3 hours, and 35%, respectively. At this optimum condition, more than 90% of neodymium could be recovered. Concentration of neodymium acetate in acetic acid. The optimum condition for the recovery of neodymium acetate crystal from the leached solution was that the initial leaching solution was evaporated until the remaining volume was about 1/5 of the initial volume. At this condition, 67.5% of neodymium was recovered from the leached solution. The neodymium remaining in the concentrated solution was recovered by reacting it with oxalic acid.

• Applied Chemistry for Engineering
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• v.24 no.3
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• pp.260-265
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• 2013

In this study, nano-emulsions containing 0.01, 0.03, 0.05, and 0.10% ethyl acetate fraction of Hippophae rhamnoides (H. rhamnoides) leaf extracts were prepared. The particle size, particle size distribution and skin permeability of the nano-emulsions were evaluated for five weeks. Nano-emulsion was prepared by the sequential use of homogenizer and microfluidizer. Nano-emulsion containing the ethyl acetate fraction exhibited a monodispersed form. Nano-emulsion containing 0.03% ethyl acetate fraction was the most stable for five weeks. The in vitro skin permeation study of nano-emulsion containing 0.03% ethyl acetate fraction was carried out using Franz diffusion cell. The nano-emulsion showed a better skin permeability than that of O/W emulsion. These results indicate that the nano-emulsion containing the ethyl acetate fraction of H. rhamnoides leaf extract showed a remarkable stability and skin permeability than that of O/W emulsion.

• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.339-345
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• 2019

The present study aims to investigate the potential applications of Aristotelia chilensis (A. chilensis) extracts as novel cosmetic materials. The total extracts of A. chilensis were partitioned into chloroform (CHCl₃), ethyl acetate (EtOAc), and distilled water (DW) fractions. A. chilensis extracts exhibited no cytotoxicity toward HaCaT human keratinocyte and B16F10 mouse melanoma cell lines. CHCl₃, EtOAc, and DW extracts reduced oxidative stress, and EtOAc extract was superior to glutathione, a natural human antioxidant positive control. The extracts of A. chilensis reduced melanin synthesis in cells treated with α-melanocyte-stimulating hormone. The extracts of A. chilensis exhibited antibacterial effects toward Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and Pseudomonas aeruginosa (P. aeruginosa). In particular, the EtOAc extract was effective in terms of antibacterial activity against S. aureus. In the present study, we identified several potential applications of A. chilensis extracts in terms of novel antioxidant and whitening cosmetic materials as well as antibacterial preservatives.

• Food Science and Preservation
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• v.9 no.1
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• pp.92-96
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• 2002

The nitrite-scavenging and antimutagenic effects of various solvent extracts from different parts of the loquat. were investigated to develope as source of functional food. The nitrite-scavenging and antimutagenic effects of fractions obtained from methanol extract were most highest in ethyl acetate fraction. Ethyl acetate fraction showed better results in the nitrite scavenging activity of 80% in leaf, 81% in seedless fruit, 73% in peel and 63% in seed. The antimutagenic effect showed strong ethyl acetate fraction of 53.1%, 48.3% in leaf and seedless fruit. The antimutagenic effect increased with increasing concentration of ethyl acetate fraction against mutagenicity induced by direct mutagen of IQ in Salmonella typhimurium TA 100. Addition of 2.5 mg and 5 mg of ethyl acetate fraction showed inhibitory effect of 65.5%, 71.2% in leaf and 63.4%, 69.2% in seedless fruit, respectively.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.189-193
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• 2011

To investigate the physiological activities of hot water extract and solvent fractions isolated from Pleurotus ferulea, antioxidative, fibrinolytic, thrombin inhibitory, and ${\alpha}$-glucosidase inhibitory activities were examined. Pleurotus ferulea, hot water extract was fractionated into hexane, chloroform, ethyl acetate, butanol and water fraction. Each of these was assayed individually. The antioxidative activities of ethyl acetate and butanol fractions were 86.79% and 87.82%, respectively. Using the fibrin plate method, only the ethyl acetate fraction showed a plasmin activity of 0.08 units/ml. Thrombin inhibitory activities of chloroform and ethyl acetate fractions were 74.90% and 71.08%, respectively. In the ${\alpha}$-glucosidase inhibitory activity test, butanol fraction showed the highest activity at 49.67%. From the above results, we anticipate that solvent fractions of Pleurotus ferulea can be used as a materials for the development of biofunctional foods for cardiovascular diseases.