• The monthly packaging world
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• s.102
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• pp.150-153
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• 2001

• The monthly packaging world
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• s.71
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• pp.152-155
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• 1999

• Journal of Applied Biological Chemistry
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• v.60 no.2
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• pp.185-190
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• 2017

Antioxidative ability of 50% ethanol extract from leaves of Leucaena leucocephala (Lam.) de Wit was investigated. The extraction yield, total polyphenols and total flavonoids of the ethanol extract were $18.3{\pm}0.40%$, $121.3{\pm}11.04{\mu}g$ gallic acid equivalents/mg and $105.2{\pm}2.77{\mu}g$ quercetin equivalents/mg, respectively. The ethanol extract possessed the antioxidative activities such as free radical, cation radical, and nitrite scavenging activities as well as reducing power and lipid peroxidation inhibitory activity. These antioxidative activities of the ethanol extract increased in proportion to the extract concentration. $EC_{50}$ values for free radical scavenging, cation radical scavenging nitrite scavenging, and reducing power were $133.51{\mu}g/mL$, $667.22{\mu}g/mL$, 2.58 mg/mL, and $250.00{\mu}g/mL$, respectively. Polyphenols and flavonoids are suggested to be the key contributors for the antioxidative ability of the ethanol extract from Leucaena leucocephala leaves.

• The monthly packaging world
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• s.50
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• pp.146-149
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• 1997

• Korean Journal of Plant Resources
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• v.27 no.2
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• pp.111-118
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• 2014

Contents of phenolics, flavonoids, and catechins, and antioxidant activity were investigated in the ethanol extracts of three different flower species, Magnolia denudata, Prunus mume, Carthamus tinctorius. Total phenolics were more present in M. denudata than P. mume or C. tinctorius, ranging from 72.6 to 118.0 mg/kg (p < 0.05). Total flavonoids level had same tendency to total phenolics content, showing highest amount (25.1 mg/kg) in M. denudata. The antioxidant activity of the methanol extracts from all the flowers dose-dependently increased. DPPH free radical scavenging activity at 250 mg/kgwas higher in M. denudata and P. mume by 93.0 and 92.6%, respectively, than C. tinctorius by 23.0% (p < 0.05). Total catechins content including 6 compounds was higher in M. denudate (9,425.5 mg/kg) than that in P. mume or C. tinctorius (3,407.8 or 190.6 mg/kg). However, P. mume extracts showed highest amount in caffeine as well as vitamine C. DPPH radical scavenging activity in three different flowers was highly correlated with contents of total phenolics ($r^2=0.7994$), total flavonoids ($r^2=0.9131$), and total catechins ($r^2=0.5929$), and their content and activities were different depending on species.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.97-104
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• 2005

In this study, the change of water content, pH, and combustion weight on the decomposition of poly ester vinyl and high density poly ethylene were examined. The poly ester vinyl was degraded by microorganism in food wastes for 30 days, while high density poly ethylene vinyl was not degraded. Also, the poly ester vinyl was rapidly degraded after the 10 days of operation and its weight was decreased. In the combustion reaction between $300^{\circ}C$ and $600^{\circ}C$, complete combustion was performed. Due to the degradation of poly ester vinyl by microorganism in food waste, the pH was increased from 4.26 to 7.6. During of 60 days operation, poly ester vinyl was degraded over 90%.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.113-115
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• 2016

온실가스의 주범을 친환경적으로 활용한다는 측면과 carbon source를 영구적으로 저렴한 비용으로 공급할 수 있다는 경제적 측면에서 CO2를 활용한 고부가가치 화학물질의 합성이 최근에 주목 받고 있다. 본 연구에서는 살렌(salen)-전이금속 착물을 단일 촉매로 사용한 모델 시스템을 통해 고부가가치 소비재의 주된 원료인 고리형 카보네이트 (cyclic carbonate)와 폴리카보네이트 (polycarbonate)가 생성되는 반응경로를 규명하였으며, 이들의 활성화 에너지를 조절함으로써 생성물을 선택적으로 합성할 수 있다는 이론적 근거를 제시하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.110-115
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• 1991

일반적으로 거의 모든 재료의 기계적인 물성치들이 여러가지 하중조건에 의해 변화하는데 그 중 탄성계수는 하중속도, 온도, 재료의 특성에 따라 변화한다. 지금까지 국내에서의 연구동향을 보면 하중속도가 탄성계수에 미치는 영향에 대한 연구보고는 미약한 실정이다.(중략)

• Food Science and Industry
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• v.43 no.3
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• pp.48-54
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• 2010

• Polymer(Korea)
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• v.27 no.1
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• pp.3-8
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• 2003

Polysiloxanes with methacrylate groups at both terminals were synthesized by a hydrosilylation reaction between allyl methacrylate and hydride-terminated polysiloxanes. The polysiloxane methacrylates with high molecular weights could be prepared through the reaction of polysiloxane methacrylates and octamethylcyclotetrasiloxane with an acid catalyst. The structures of the prepared polysiloxane methacrylates were verified by $^1$H- and $^{29}Si-NMR.$ The polysiloxane methacrylates were freely miscible with silicone oils. Polysiloxane films with microphase-separated liquid silicone oil were prepared by photo-crosslinking the mixture of polysiloxane methacrylates and silicone oil. Scanning electron microscopy (SEM) of the films showed that the size of silicone oil droplets became smaller with a lower loading of silicone oil, lower molecular weight of polysiloxane methacrylate, and lower molecular weight of silicone oil.