• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.204-204
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• 1994

Ganoderma lucidum의 균사체로 부터 얻어진 G009의 이화학적 특성을 규명하였다. G009는 넓은 범위의 분자량 분포를 가지고 있는 다당체로 분자량 9.4kD의 물질이 주성분이었다 G009의 당의 함량은 약 70%이었고 단백질은 약 2.4%인 것으로 나타났다. G009의 주요 구성당은 glucose, xylose, mannose, galactose 등이었고, glycine, leucine, alanine, valine, isoleucine, proline 등 17종의 아미노산이 확인되었다. 유기원소 분석 결과 G009는 탄소 약 40%, 수소 5.7%, 질소 1.8%의 구성비를 보였으며, 무기원소 분석결과 Ca, Mg, Zn 등이 확인되었다. 이상의 결과로 부터 G009는 9.4 kD의 분자량을 갖는 단백다당체를 주성분으로 하는 당화합물로 추정된다.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.211-214
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• 2001

최근 입자를 이용한 색전술의 재료로서 광범위하게 사용되는 폴리비닐알코올(poly (vinyl alcohol) (PVA)) 입자는 전형적인 혼성배열(atactic)이다[1]. 제조된 PVA 입자가 고내구성 및 혈액내에서 안정성을 나타내기 위해서는 중합된 PVA 입자의 분자량 뿐만 아니라 교대배열성(syndiotacticity)도 커야 한다. 교대배열기(sydiotactic group)를 풍부하게 함유하고 있는 고분자량의 PVA를 제조하기 위해서는 고분자량의 교대배열성 전구체가 얻어지도록 입체장애를 일으키는 에스테르기를 보유하고 있는 단량체를 사용하거나 중합방법을 개선하는 것이 필요하다. (중략)

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.190-196
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• 1998

A new sampling and size exclusion chromatography (SEC) method for the analysis of underivatized cellulose are established. In this method, cellulose materials are first dissolved in N-methylmorpholine N-oxide (NMMO) and diluted by adding dimethyl sulfoxide (DMSO) to make the sample solutions of about 0.1% in 50/50 NMMO/DMSO (w/w). Sample solutions are analyzed using a glucose-treated divinylbenzene (DVB) SEC column and DMSO containing 0.05M LiBr and 2.5 blank as the eluant. The flow rate was constant at 1 mL/min and the whole SEC system including the column was heated at $80^{\circ}C$ to reduce the viscosity of DMSO. Addition of 0.05 M LiBr eliminated SEC baseline drifting, and addition of 2.5 blank seems to reduce the interaction between the sample and the column packing. SEC molecular weights were determined using a calibration curve constructed from a series of narrow pullulan standards, and they were used to measure the degree of degradation during two different pulp-to-sponge processings.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.432-437
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• 1999

Pyrolysis of polyethylene was carried out in the stainless steel reactor of internal volume of $10cm^3$. Pyrolysis reactions were performed at temperature $390{\sim}450^{\circ}C$ and the pyrolysis products were collected separately as reaction products and gas products. The molecular weight distributions(MWDs) of each product were determined by HPLC-GPC and GC analysis. Distribution balance equation for MWDs of random and specific products were proposed to account for initiation-termination and propagation-depropagation, such as hydrogen abstraction, chain cleavage, coupling of polymer and radical. A separate chain-end scission process produces low molecular weight noncondensable gases(C1 through C5) of average molecular weight 38. Activation energies of the random-chain scission and chain-end scission rate parameters, respectively, were determined to be 35, 17 kcal/mole.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.48-53
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• 1999

The study was carried out to investigate the effects of hydrolysis conditions such as treatment times and concentrations on the solubility of insoluble sericin using the hydrochloric acid solution. When insoluble sericin was hydrolyzed by HCl solution, the solubility was increased with the higher treatment concentration. As the results of electrophoresis of sericin powder obtained by the HCl treatment, a distinguishable band was not confirmed. Average degree of polymerizations(A.D.P.) of sericin hydrolyzed by HCl solution were about 4.2~5.9 and average molecular weights(M.W.) were about 470~670. The longer hydrolysis time reduced the whiteness of sericin powder. As the results of amino acid analysis, the amino acid compositions of the sericin powder from HCl treatment were sililar to that of insoluble sericin, but Tyr. and Arg. were not detected in the powder obtained by HCl treatment. In DSC analysis, thermal deformation and pyrolysis peak located at near 220$^{\circ}C$ and 330$^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.857-865
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• 2017

This study was conducted to analyze and characterize the properties of polyethylene wax polymerized and polymerized using various metallocene catalysts based on Indene and Cyclopentadien, which are different from Ziegler-Natta catalysts used in polyethylene polymerizatio n. The polymerization of polyethylene wax was carried out under various conditions by adjusting the polymerization temperature and the ratio of hydrogen gas used as a chain transfer agent and ethylene gas to metallocene catalysts containing ligands of different structures. The molecular weight and molecular weight distribution, The catalyst yields were compared and analyzed. As a result, the structure of a metallocene catalyst suitable for having a low molecular weight and a narrow molecular weight distribution was proposed and the ideal polyethylene wax could be polymerized.

• The Korean Journal of Zoology
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• v.30 no.3
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• pp.261-271
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• 1987

계배 중추신경계의 분화에 따른 단백질 합성 양상을 SDS-PAGE와 2차원 전기영동으로 분석하였다. 약 24∼26개의 band가 densitomete떼 의해 기록되었고, 주요 band들의 분자량은 90K에서 lIft 범위에 분포하였다. 대뇌, 시엽 및 소뇌에서 가장 현저한 band는 분자량이 44.7K로 actin으로 사료되었다. 대뇌의 85.5광 및 47.9K, 시엽의 85.5K, 71.6K 및 34.9K 소뇌의 47.9K 및 34.9K band들은 부화전까지 는 증가하다가 부화후 감소하였다. 기록된 약 300개의 polypeptide중 약 9%가 분화가 진행됨에 따라 그들의 합성율에 변화를 보였으며, 대뇌의 spot 19(Mr, 63K; pl, 6.95)와 소뇌의 spot 22(Mr, 43K; pI, 6.5) 는 부화후 4일배에서 새로이 합성되었다.

• Membrane Journal
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• v.13 no.2
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• pp.81-87
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• 2003

The permeation experiments f3r the aqueous dextran solutions of which the molecular weights were distributed between several thousands and million daltons were carried out using the dead-end cell system equipped with sheet membrane to determine the molecular weight cut-off (MWCO) of ultrafiltration membranes. The dextran rejections with respect to molecular weight were obtained by GPC analysis of feed and permeate solutions, then the MWCO was decided as the dextran molecular weight corresponding to the 90% rejection. The MWCO of PBTK membrane manufactured by Millipore was varied between 63,000 and 68,000 daltons as the pressure increased from 0.5 to 2.0 bar. However, the MWCO of PBQK(Millipore) and UE 1812(Saehan) under the above operating pressure increased to 3.5 and 4.3 times, respectively. Also, the MWCO of PBTK increased to 25% as the membrane permeation increased from 10 to 40% of the feed solution.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.2
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• pp.241-246
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• 2004

To develop novel anti-aging peptides from the germinated black rice, we treated with bromelain, papain and Pronase E. And we investigated the effects of the germinated black rice peptide (GBRP) as anti-aging cosmetic ingredients, and compared with the non-germinated black rice protein (NBRP). We investigated the effects on in vitro inhibition of matrix-metalloprotease (MMP), proliferation of human skin fibroblasts, stimulation of collagen synthesis and expression of UVA-induced MMPs in human skin fibroblasts, UVA induced MMP-1 expression and collagen contents in human skin fibroblasts were analyzed by enzyme-linked immunosorbent assay (ELISA). As a result, the molecular weight distributions of GBRP and NBRP were determined by gel permeation chromatography to be approximately 900 and 10,000 daltons. GBRP increased skin cell proliferation about 40% and reduced UVA-induced MMP-1 expression about 50%. Also the collagen protein level of cells, which were cultured with GBRP, was increased about 25%. These results suggest that the geminated plant seed peptides can be novel anti-aging ingredients for cosmetics.

• Proceedings of the Korean Environmental Health Society Conference
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• 2001.04a
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• pp.65-66
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• 2001