• 폴리머
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• 제37권5호
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• pp.587-591
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• 2013

Poly(3,4-ethylenedioxythiophene)(PEDOT)은 높은 전기 전도도, 광학적 투과성 및 좋은 화학적 안정성을 가지고 있는 반면 낮은 물리화학적 물성을 가지고 있다. 본 연구의 목적으로 PEDOT의 내용제성 및 필름경도와 같은 물리화학적 특성을 향상시키고자 하였다. 음이온성 수성폴리우레탄(WPU)이 가지는 카르복실기는 아지리딘 존재 하에서 효과적인 가교반응이 일어나 물리화학적 특성이 개선된 WPU/PEDOT 혼성 전도성 박막을 제조할 수 있다. 다양한 WPU 및 고형분 함량별로 WPU/PEDOT 유기-유기 혼성 박막을 제조하여 전기적/물리화학적 특성을 비교하였다. 고형분 함량이 증가할수록 투과율과 표면저항은 감소하였다. WPU/PEDOT 혼성 전도성 박막의 연필경도와 내용제성이 WPU가 가지는 카르복실기의 가교반응에 인해 효과적으로 증가하였다.

• 한국식품저장유통학회지
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• 제22권6호
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• pp.796-803
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• 2015

본 연구에서는 다양한 생리활성을 가진다고 알려져 있는 블루베리의 식품 산업에서의 이용 증대를 목적으로 블루베리 유산균 발효물을 제조하였으며 이화학적 특성 및 저장 안정성을 조사하였다. 생균수는 발효 72시간에서 가장 높은 5.96 log CFU/mL를 나타내었으며, pH 및 산도는 각각 발효 시간 경과에 따라 유의적으로 감소 및 증가하였다. 총 안토시아닌 및 cyanidin-3-glucoside(C3G) 함량은 발효 72시간에서 각각 100 g 당 31.52 mg 및 5.41 mg으로 가장 높은 함량을 나타내어 생균수, 총 안토시아닌 및 C3G 함량을 고려하여 72시간을 최적 발효 구간으로 선정하였다. 블루베리 발효물의 L값 및 a값은 발효 후 감소하고, b값 및 ${\Delta}E$값은 증가하였으며, 총 폴리페놀 및 총 플라보노이드 함량은 100 g당 2.21 g 및 0.91 g으로 발효 전에 비해 높게 나타났다. 항산화활성은 DPPH 및 superoxide radical 소거 활성에서는 블루베리 발효물에서 각각 30.74% 및 52.76%를 나타내어 무발효물 보다 높은 소거활성을 나타내었으며, FRAP에서도 $256.42 {\mu}M$을 나타내어 블루베리 발효물에서 높은 항산화 활성을 나타내었다. 블루베리 발효물의 저장안정성은 총 안토시아닌 및 C3G 함량의 감소율로 확인하였는데, 42일 경과 후 48.03% 및 38.71% 감소하여 무발효물에 비해 우수하였다. 따라서, 블루베리 발효물은 유용물질 증가로 인한 안정성 향상을 통해 식품가공 산업에서의 활용증진이 기대된다.

• Journal of Pharmaceutical Investigation
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• 제34권1호
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• pp.29-34
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• 2004

The solubility and stability of quercetin in various vehicles were determined. The solubility of quercetin at $28^{\circ}C$ increased in the rank order of isopropyl myristate < oleyl alcohol < propylene glycol monolaurate < oleoyl macrogol­6 glycerides < linoleoyl macrogol-6 glycerides < propylene glycol laurate (PGL) < propylene glycol monocaprylate (PGMC) < polyethylene glycol-8 glyceryl linoleate < caprylocaproyl macrogol-6 glycerides < diethylene glycol mono ethyl ether (DGME). The addition of DGME to non-aqueous vehicles such as PGL ad PGMC markedly increased the solubility of quercetin. From the stability studies, it was found that quercetin was unstable due to rapid oxidation by dissoved oxygen. The addition of a combination of ascorbic acid and edetic acid (EDTA) at 0.1 % markedly decreased the degradation rates of quercetin in 40% polyethylene glycol 400 in saline. Quercetin was relatively unstable in non-aqueous vehicles such as PGL and PGMC alone, and PGL-PGMC co-solvent The degradation of quercetin in such non-aqueous vehicles was fast, depending on temperature. The addition of butylated, hydroxytoluene, butylated hydroxyanisole, citric acid and/or EDTA at 0.1 % was effective in retarding the degradation of quercetin.

• 한국유가공학회:학술대회논문집
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• 한국유가공기술과학회 2005년도 제61회 국제 유가공 심포지움
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• pp.11-19
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• 2005

Heat treatment is essential for hygienic safety and for extending shelf-life of milk. Heating of milk affects principally its physicochemical, nutritional and organoleptic properties. The most important changes are the decrease in whey protein solubility and the decrease in stability of casein micelles. Maillard reactions are also important and undesirable consequences.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.132.3-133
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• 2003

The purpose of this study was to investigate the effect of manufacturing process for food on allergenicity of soybean or soybean products. Crude extracts of each soybean (SB), weaning diet A (WA) and B (WB) or soybean paste C (SC) and D (SD) were digested a simulated gastric fluid (SGF) to characterize the physicochemical stability of allergens. Allergens of each smaple except a SB (82, 39, 35 kDa) were not rapidly digested in SGF. The endogenous allergens in each sample were separated by gel electrophoresis and immunobloted with serum from soybean-sensitive patients of normal subjects. (omitted)

• 한국세라믹학회지
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• 제32권2호
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• pp.217-226
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• 1995

Alumina powders were dispersed using crosslinkable organic molecules by electrosteric stabilization and then consolidated by crosslinking of organic molecules. The effect of processing variables such as the physicochemical properties of both solvent media and organic molecules, the proportions of mixed organic media, etc. were studied. FT-IR was used todeduce the mechanism of organic molecules adsorption on the alumina particle surfaces. The adsorption characteristics and the electrokinetic behavior of alumina suspensions were correlated with the stability of particle in alumina suspension using rheological measurements. The green body of alumina consolidated by the chemical crosslinking of the adsorbed organic molecules after the alumina suspension had been stabilized was tough enough for green machining and the sintered alumina fabricated by this proposed process also showed a high bending strength and a homogeneous microstructure.

• 한국식품조리과학회지
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• 제9권4호
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• pp.293-297
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• 1993

This study aims to seek ways to improve frying stability of soybean oil which is widely used for deep frying while at the same time attempting to develop new frying oil and fat of high quality. Taking soybean oil as a control group, the study fried frozen potatoes with hydrogenated soybean oil with iodine value ranging from 60 to 110 for 15 hours. The test results showed that in frying stability, hydrogenated soybean oil with iodine value of 87 and 63 was superior to normal soybean oil and hydrogenated soybean oil with iodine value of 111(P<0.05). In sensory evaluation, however, no significant difference can be detected among groups(P>0.05). The correlation between physicoche-mical properties and sensory evaluation results was highest for smoke point and viscosity. This study concludes, therefore, that hydrogenated soybean oil with iodine value of 60~90 is better than normal soybean oil as deep-frying oil.

• Biomolecules & Therapeutics
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• 제8권4호
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• pp.332-337
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• 2000

Physicochemical properties of aspalatone (acetylsalicylic acid maltol ester, AM), which has been recently found to have an antithrombotic effect, were studied in terms of solubility, dissolution, partition coefficient (Pc) and stability. The solubility of AM at 37$^{\circ}C$ was about 1.2 mg/ml and the P$_{c}$ value for n-octanol/water and chloroform/water was 11.4 and 382.6, respectively. Dissolution rates of AM at pH 1.2 and 6.8 were more than 80% within 30 min. The degradation of AM followed apparent first-order kinetics, and was dependent on temperature, pH and ionic strength. From the pH-rate profile, the optimal pH was found to be at around 4.0. Half-lives at pH 1.2 and 6.8 were 33.5 and 44.4 hr, respectively. The degradation rate of AM at pH 1.2 was somewhat faster than that of aspirin, but at pH 7.0, the degradation rate of AM was slower than that of aspirin.n.

• 한국재료학회지
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• 제16권10호
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• pp.599-605
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• 2006

N-(3-triethoxysilylpropyl)-1,4-diaminoanthrquinone-2,3-dicarboximide (TESP-DADI), an organic blue pigment, has been prepared and incorporated into silica solid matrix reacting triethyl orthosilicate (TEOS) via sol-gel method. Morphology and microstructure of resulting hybrid pigment were studied employing SEM and TEM. The micrographs and particle size distributions showed that uniform pigment can be obtained employing TEOS-based sol-gel method forming silica core. Particle size distribution of dispersed pigment in water was examined using the technique of dynamic light scattering. The ensuing pigment dispersion ink was subjected to various physicochemical evaluation such as viscosity, surface tension, inkjet stability, storage stability, and color change as inkjet ink using spectrophotometric, and microscopic techniques.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.267.1-267.1
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• 2002

The potential allergenicity of the transgene products in genetically modified organisms (GMOs). has been an important issue. As a part of the risk assessment of GMOs. we investigated the physicochemical stability and the immunogenicity of food allergens to determine their allergenicity. We have systematically evaluated the stability of food allergens in the gastrointestinal tract by using simple models of gastric (Stimulated gastric fluid) and intestinal (Stimulated intestinal fluid) digestion. (omitted)