• 한국식품위생안전성학회지
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• 제5권1호
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• pp.35-40
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• 1990

유산균이 생성하는 다당류에 관한 연구의 일환으로서 Str. themophilus 와 Lb. bulgaricus를 10% 환원탈지유와 12% 환원전지유에 배양하면서 다당류 생성에 따른 우유 배양액 점도의 경시적 변화 및 그의 유체역학적인 특성에 대하여 조사하였다. 1. Str. themophilus 510의 10% 탈지유 배양액의 의가소성 유체의 유동양식을 가장 강하게 나타냈다. 한편 14% 농도에서 가장 높은 점도의 경시적 변화 및 그의 유체역학적인 특성에 대하여 조사하였다. 1. 12% 전지유배양액의 경우 의가소성유체의 유동양식을 나타내지만 탈지유 배양액에 비해서 현저한 점도의 저하를 나타냈다. 1. Str. themophilus 510 배양액의 최대 점조도 계수와 최소 유동지수는 각각 43, 0.09 이며 Lb. bulgaricus는 35, 0.09이다.

• 약학회지
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• 제60권2호
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• pp.73-77
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• 2016

Alginic acid and carboxymethyl cellulose sodium are dietary fibers from plants. They have a swelling property and delay the gastric emptying time, thereby resulting in feeling satiated after oral administration, which may eventually contribute to loss of body weight. The goal of this study was to compare swelling property of three commercial matrix tablets based on alginic acid and carboxymethyl cellulose sodium. When the swelling was determined by the Korean Ministry of Food and Drug Safety (MFDS) guideline, the tablet prepared by direct compression method with highly viscous swelling agent showed the highest swelling in acidic conditions. Water uptake of these tablets was rapid and completed within 30 min. Moreover, when the pH was changed from 2.5 to 6.8 buffer, the water uptake was not significantly changed in all tablets.

• Elastomers and Composites
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• 제49권3호
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• pp.191-198
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• 2014

산성기를 도입한 폴리우레탄에 나노산화아연을 첨가하여 열가소성 폴리우레탄 탄성체를 합성하였으며, 합성된 폴리우레탄 탄성체의 기계적물성, 열적특성, 접촉각, 그립특성을 평가하였다. 그리고 산화아연의 함량과 입자 크기가 폴리우레탄 탄성체에 미치는 영향에 대해서 연구하였다. 나노산화아연을 도입한 경우 이온결합이 형성되어 산성기에 의한 수소결합과 동시에 작용하기 때문에 인장강도, 마모 등 기계적 물성 및 그립특성이 향상되는 것이 확인되었다. 폴리우레탄내의 산화아연 함량에 따른 물성평가 결과 나노산화아연 함량이 증가할수록 이온결합 도입에 의한 친수성이 커져서 wet slip이 지속적으로 상승되었으며, 기계적 물성은 산화아연에 의한 이온화율 50%까지 향상되다가 그 이후에는 감소되는 현상을 나타내었다.

• 한국주조공학회지
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• 제31권4호
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• pp.191-197
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• 2011

Transparent organic materials have been frequently used as an analog of the solidifying metallic materials, because their transparency permits an in-situ observation of the microstructural development during solidification through optical microscopy. Pivalic acid (PVA)-ethanol system showing an anisotropic property in solid-liquid interfacial energy and interface kinetics was adopted in the present experiment, and the detailed experiments performed are as follows: (1) variation of dendrite tip temperature with growth velocity, (2) correlation between primary dendrite arm spacing (${\lambda}_1$) and the growth orientation away from the heat flow direction (tilt angle: ${\theta}$), (3) variation of dendrite tip radius (R) with growth velocity (V), (4) dendrite tip stability parameter (${\sigma}^*$) and its dependence on the concentration. Concerning the correlation between the dendrite tip temperature and growth velocity the present result is well suited to Hunt-Lu equation. As the tilt angle increases, the average primary dendrite spacing tends to increase.

• 방사선산업학회지
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• 제5권4호
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• pp.371-376
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• 2011

The surface property of the materials used in tissue engineering application has been essential to regulate cellular behaviors by directing their adhesion on the materials. To modulate surface property of the synthetic biodegradable materials, a variety of surface modification techniques have used to introduced surface functional groups or bioactive molecules, recently polydopamine coating method have been introduce as a facile modification method which can be coated on various materials such as polymers, metals, and ceramics regardless of their surface property. However, there are no reports about the degree of polydopamine coating on the materials with different hydrophilicity. In the present study, we prepared acrylic acid grafted nanofibrous meshes using electron-beam irradiation, and then coated meshes with polydopamine. Polydopamine successfully coated on the all meshes, both properties of acrylic acid and polydopamine were detected on the meshes. In addition, the degree of polydopamine deposition on the materials has been altered according to surface hydrophilicity, which was approximately 8-times greater than those on the non-modified materials. In conclusion, dual effect from the acrylic acid grafting and polydopamine may give a chance as a alternative tool in tissue engineering application.

• 한국염색가공학회지
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• 제12권1호
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• pp.44-51
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• 2000

The conventional one bath exhaust dyeing system of nylon]/cotton blends with acid dye/direct dye involves a lot of neutral salt which affect dyeability of acid dyes. Because of conventional one bath exhaust dyeing system of nylonl/cotton blends with acid dye/direct dye needs acid dyes adjusted at a neutral liquor, suitable acid dye is limited. To improve dyeing property of nylon/cotton blends, cotton component was pretreated with cationizing agent containing chlorohydrine group in aqueous solution of sodium hydroxide. This study was carried out to investigate dyeing possibilities of nylon/cationized cotton blends with acid dye/direct dye in a non-neutral salt dyebath by one bath two step method. The concentration of direct dye was 1.0%, 0.7%, 0.3%o.w.f. respectively at a non, 1%, 3%owf of reserving agent for being almost equal color strength between nylon and 3% cationized cotton when nylon/3% cationized cotton blends was dyed with acid dye/direct dye at concentration of acid dye(1%o.w.f.) by one bath two step method.

• 한국염색가공학회지
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• 제15권5호
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• pp.285-293
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• 2003

Waterborne PU membrane was prepared from waterborne PU dispersion solution to investigate physical and staining properties. The staining properties of waterborne PU membrane with acid dyes and disperse dyes were observed. The physical properties of the PU membrane were investigated by X-ray diffraction and IR spectroscopy. The staining property of waterborne PU membrane for azo acid dyes is better than that of disperse dyes. X-ray diffraction peaks sharpened and tensile strain and stress increased with heat setting temperature.

• Archives of Pharmacal Research
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• 제17권5호
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• pp.375-377
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• 1994

Thirteen kinds of naturally occurring or derivatised thiterpenes, reported to have an antitumoral property, were reinvestigated on the basis of their direct cytotoxicity or the inhibitory activity on cell growth against five kinds of cultured human tumor cells, i.e., A-549, SK-OV-3, SK-MEL-2, XF-498 and HCT15, in vitro. Ursonic acid III, betulinic acid VIII, betulonic acid X and glycrrhetinic acid XI were exhibitied a marked inhibition on cell growth.

• 약학회지
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• 제52권2호
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• pp.131-136
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• 2008

Sesamol, one of constituents isolated from sesame seed (Sesamum indicum L.) has been known to have natural antioxidant property. Nicotinic acid and clofibric acid have been used for treatment of hyperlipidemia. Sesamol derivatives prepared by conjugation with nicotinic acid (SJ-301) and clofibric acid (SJ-302) were expected to have various biological activity caused by synergistic effect of sesamol. Thus, this study were carried out to investigate the synthesis of sesamol derivatives from seasamol and antihyperlipidemia drugs and their biological activities. As a result, SJ-301 showed a stronger antihyperlipidemia activity in vivo and inhibitory effect on $TNF-{\alpha}$ release in vitro compared to the original agents such as sesamol, nicotinic acid and clofibric acid.

• 생명과학회지
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• 제9권6호
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• pp.737-742
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• 1999

천일염에서 분리된 고호염성균인 Haloarual sp. EH-1으로부터 PHA를 생산하여 PHA의 구조 및 성질 등을 검토하였다. 그 결과는 다음과 같다. PHA를 GC chromatogram, IR 및 300MHz H-NMR로 분석한 결과 Haloarcnly sp. EH-1으로부터 추출된 PHA는 3-hydroxybutyric acid와 3-hydroxyvaleric acid 와 3-hydroxyvaleric acid의 중합체인 PBB/HV로 추정되었으며, thermal property는 $152.46^{\circ}C.$ 점도는 1.25dl/g 그리고 분사량은 $1.44 X 10^5$이었다.