• 대한가정학회지
• /
• 제28권4호
• /
• pp.41-50
• /
• 1990

Soy protein was isolated from Korean soy bean 'Chang ryub' and chemically modified with succinic anhydride. Functionality of the soy protein isolate(SPI), succinylated SPI(SPPI), and PP590(commercial) at various pH were investigated. The mechanical and sensory properties of soy bean curds made from several mixing ratio of succinylated soy bean milk were observed. The solubility of SPI significantly increased with succinylation. The solubility of PP590 was lower than that of SSPI. The solubility of SPPI increased significantly in 0.03M CaCl2 solution. The emulsifying activity of SSPI increased. On the range of pH above pI the emulsifying activity of PP590 was higher than that of SPI. There was no difference in emulsion stability among the groups. The foam expansion capacity of SPPI increased at higher pH than pI but the foam stability decreased significantly above pH 9. Mechanical texture profile analysis revealed the modified soy bean curds had the lower hardniss, chewiness and cohesiveness with increased modification. The mechanical characteristics of modified soy bean curds revealed generalized Maxwell Model of 7-elements or 5-elements. In sensory evaluation, the hardness, the springiness and acceptability of modified soy bean curds were lower significantly than those of control soy bean curd.

• 대한치과교정학회지
• /
• 제5권1호
• /
• pp.21-24
• /
• 1975

The purpose of this study was to investigate the effect of sinc phosphate cement on the enamel surface of extracted teeth. The tooth was placed in a test tube, which was subjected to 5ml of 0.2M acetate buffer at pH 4 by 'window technique.' The calcium content of the acetate buffer was determined by the Perkin-Elmer Model 303 Atomic Absorption Spectrophotometer. The obtained results were summarized in the following. 1. The solubility of enamel is $0.92mg/cm^2$. ml in control group. 2. The solubility of enamel is increased by treating these with zinc phosphate cements. 3. The solubility of enamel is $0.69mg/cm^2$. ml by treating with Lee Smith cement. 4. The solubility of enamel is $0.30mg/cm^2$. ml by treating with G-C's cement.

• 한국지구과학회지
• /
• 제25권1호
• /
• pp.39-47
• /
• 2004

In the FMAS system the effect of iron on alumina solubility in orthopyroxene has been determined by experiments with crystalline starting mixtures of garnet and orthopyroxene of known initial compositions at 20 kb, 975$^{\circ}C$ and 25 kb, 1,200$^{\circ}C$. These data have been modeled to develop a thermodynamic method for the calculation of Al$_{2}$O$_{3}$ in orthopyroxene as a function of P, T and composition. The direct application of the alumina solubility data in the MAS system to natural assemblages could lead to significant overestimation of pressure, probably by about 5kb for the relatively common garnet-lherzolites with abot 25 mol per cent Ca + Fe$^{2+}$ in garnet and about 1 wt. per cent Al$_{2}$O$_{3}$ in orthopyroxene since the effect of Fe is similar to that of Ca and Cr$^{3+}$in reducing the alumina solubility in orthopyroxene in equilibrum with garnet relative to that in the MAS system.

• Journal of Pharmaceutical Investigation
• /
• 제30권4호
• /
• pp.267-271
• /
• 2000

The effect of cyclodextrins on the solubility and stability of aspalatone (acetylsalicylic acid maltol ester, AM, CAS 147249-33-0), which has been recently found to have an antithrombotic effect, was investigated. The addition of ${\beta}-cyclodextrin\;({\beta}-CD),\;dimethyl-{\beta}-cyclodextrin\;(DMCD)\;or\;2-hydroxypropyl-{\beta}-cyclodextrin\;(HPCD)$ to the aqueous solution increased the solubility of AM concentration-dependently. From the phase solubility diagram, stability constants for $AM-{\beta}-CD$, -DMCD or -HPCD complexes were calculated to be 43.1, 78.3 and $53.0\;M^{-1}$. The addition of ${\beta}-CD$, DMCD or HPCD to AM solution retarded the degradation rate of AM in the acidic region. However, ${\beta}-CD$ and HPCD rather acted as an accelerator of degradation in the neutral and alkaline regions. DMCD had a stabilizing effect at all pHs studied.

• 약학회지
• /
• 제28권3호
• /
• pp.161-167
• /
• 1984

To improve the solubility properties of indomethacin, a poorly water-soluble drug, some attempts were made with surfactants, such as sodium deoxycholate, sodium laurylsulfate and polysorbate-80. The enhancement effect in solubility was found to be due to the micellar solubilization and dependent on the concentration of surfactants, pH and temperature. The mechanism of interaction was suggested to be attributed to the formation of mixed micelles between the drug and solubilizers.

• Restorative Dentistry and Endodontics
• /
• 제35권5호
• /
• pp.344-352
• /
• 2010

연구목적: 본 연구의 목적은 glass ionomer cement (GIC)와 혼합한 mineral trioxide aggregate (MTA)의 경화 시간, 압축 강도, 용해도, pH를 평가하고 이것을 MTA, GIC, IRM, SuperEBA와 비교하는 것이다. 연구 재료 및 방법: 경화 시간과 압축 강도는 ISO 9917, 그리고 용해도는 ISO 6876 기준에 따라 측정하였다. pH는 고체시편 전용 전극이 연결된 pH meter를 이용하여 측정하였다. 결과: GIC와 혼합한 MTA의 경화시간은 MTA보다 유의하게 짧았으며 압축 강도는 7일간 모든 시점에서 다른 재료보다 유의하게 낮았다. GIC와 혼합한 MTA 중에서 1 : 1과 2 : 1 시편의 용해도는 다른 실험군보다 유의하게 높았다. 또한 GIC와 혼합한 MTA의 pH는 혼합직후 2-4의 범위에서 1일 후 5-7 사이로 증가하였다. 결론: GIC와 혼합한 MTA의 경화시간은 MTA에 비해 개선되었으나 압축강도 및 pH와 같은 다른 성질들은 MTA에 비해 오히려 열등한 것으로 밝혀졌다. 임상적 사용이 가능하려면, MTA의 기존 장점을 저해하지 않으면서 단점을 개선하기 위한 적절한 혼합비를 찾아내고 생체친화성을 평가하는 추가적인 연구가 필수적이다.

• 한국산림과학회지
• /
• 제43권1호
• /
• pp.35-38
• /
• 1979

우리나라 특산수종(特產樹種)인 구상나무재(材)를 시료(試料)로 하여 그 추출물(抽出物)의 추출시간(抽出時間), 온도별(溫度別)에 따른 추출함량(抽出含量)의 차이(差異)와 추출액(抽出液)의 pH 변동(變動) 및 각요인간(各要因間)의 상관성(相關性)을 조사(調査)하여 본바 열수추출물(熱水抽出物)에 있어서는 변재부(邊材部)는 10시간추출(時間抽出)에 2.33% 심재부(心材部)는 12.30%였고 NaOH 추출물(抽出物)에 있어서는 1시간추출(時間抽出)에 변심재(邊心材) 평균(平均) 8.23%로서 열수처리(熱水處理)의 10시간효과(時間効果)가 있었으며 유기용제(有機溶制) 추출(抽出)에 있어서는 최초(最初)의 1시간후(時間後)에 4.00%로서 10시간처리후(時間處理後)의 추출량(抽出量) 4.44%와 크게 차이(差異)가 없었다. 추출처리(抽出處理)의 온도효과(溫度効果)를 보면 중성용제(中性溶劑)에 있어서는 추출온도(抽出溫度) $25{\pm}3^{\circ}C$, $50{\pm}3^{\circ}C$, $97{\pm}3^{\circ}C$에서 각추출량(各抽出量) 2.73%, 3.29%, 7.32%로서 추출처리(抽出處理)에서 시간(時間)보다 온도(溫度)가 더욱 절대적인 영향을 끼치는 것이 시사(示唆)되었으며 염기추출물(鹽基抽出物)에 있어서는 그 경향이 더욱 현저(顯著)하였다. 추출처리중(抽出處理中)의 pH 변동(變動)은 심변재(心邊材) 공(共)히 최초(最初)의 pH 6.5에서 10시간후(時間後) 5.4까지 떨어졌다. 추출처리중(抽出處理中)의 각처리요인(各處理要因)의 결과(結果)와의 관계(關係)는 추출량(抽出量) 시간(時間)간에는 r=0.896, 추출량(抽出量)과 온도간(溫度間)에는 r=0.986, 추출액(抽出液)의 pH와 시간간(時間間)에는 r=-0.955, 추출량(抽出量)과 부위간(部位間)에는 r=0.840의 상관성(相關性)을 보였고 전체적(全體的)으로 볼 때 추출량(抽出量)과 온도간(溫度間)에 1% 수준의 높은 상관성(相關性)을 나타내었고 가장 상관성(相關性)이 낮은 것은 유기용제처리시(有機溶劑處理時)의 심재(心材), 변재(邊材)사이 추출물함량(抽出物含量)으로서 r=0.748(5% 수준미달)이었다.

• 멤브레인
• /
• 제28권5호
• /
• pp.320-325
• /
• 2018

FASs (fluoroalkylsilanes)로 표면 개질한 소수성 막에 대한 부탄올/물, 이소프로판올/물 용액의 수착(sorption)량을 측정하였으며 이들 수착 특성을 Hansen 용해도 파라미터를 이용하여 해석하였다. 부탄올의 수착량이 이소프토판올보다 많았으며, 이는 부탄올의 용해도 파라미터(${\delta}_t=20.4$)와 FASs 소수성 막의 용해도 파라미터(${\delta}_t=16.9$)와의 차이가 이소프로판올 (${\delta}_t=24.6$)과의 차이보다 작기 때문인 것으로 설명할 수 있다. 극성력(${\delta}_p$) 측면에서 살펴보면, FASs 극성력(${\delta}_p=4.6$)과 부탄올의 극성력(${\delta}_p=6.3$)과의 차이가 FASs 극성력(${\delta}_p=4.6$)과 이소프로판올의 극성력(${\delta}_p=9.0$)과의 차이보다 작다. 이는 부탄올-FASs 간의 극성력 차이가 이소프로판올-FASs 간의 극성력 차이보다 작아서 부탄올-FASs 간의 상호인력이 크다는 것을 의미하며, 수착량이 크게 나타나는 결과를 설명할 수 있다. 본 실험결과로부터 막에 대한 알코올의 수착특성, 용매에 대한 용질의 용해도 등을 분석하는데 용해도 파라미터를 이용할 수 있음을 알 수 있다.

• 폴리머
• /
• 제34권6호
• /
• pp.553-559
• /
• 2010

The paper describes the preparation and characterization of conductive polyaniline-modified polymers by growing of aniline onto functionalized poly(styrene-co-p-methylstyrene) [P(St-co-MSt)]. For this purpose, P(St-co-MSt) was synthesized via nitroxide mediated radical polymerization (NMRP) and then N-boromosuccinimide was used for introduction of bromine to the benzylic positions of copolymer. Afterwards, 1,4-phenylenediamine was linked to the brominated P(St-co-MSt) and functionalized copolymer $[P(St-co-MSt)-NH_2]$ was prepared. The graft copolymerization of aniline monomers onto functionalized P(St-co-MSt) was initiated by oxidized phenylamine groups after addition of ammonium peroxydisulfate (APS), and p-toluenesulfonic acid-doped PANI was chemically grafted onto P(St-co-MSt) via oxidation polymerization. The obtained terpolymer was studied by FTIR and UV-Vis spectroscopy and its thermal behaviour were examined by DSC and TGA analyses. The conductivity of terpolymer was measured by four-point probe method and electroactivity was measured by cyclic voltammetry (CV). The solubility of P(St-co-MSt)-g-PANI was examined in common organic solvents.

• Restorative Dentistry and Endodontics
• /
• 제47권1호
• /
• pp.10.1-10.11
• /
• 2022

Objectives: This study aimed to investigate the color stability, solubility, and surface characteristics of 3 calcium silicate-based cements (CSCs) after immersion in different solutions. Materials and Methods: ProRoot white mineral trioxide aggregate (MTA), Biodentine, and Endosequence Root Repair Material (ERRM) were placed in cylindrical molds and stored at 37℃ for 24 hours. Each specimen was immersed in distilled water, 5% sodium hypochlorite (NaOCl), 2% chlorhexidine, or 0.1% octenidine hydrochloride (OCT) for 24 hours. Color changes were measured with a spectrophotometer. Solubility was determined using an analytical balance with 10^-5 g accuracy. The surface characteristics were analyzed using scanning electron microscopy and energy-dispersive spectroscopy. Data were analyzed using 2-way analysis of variance, the Tukey test, and the paired t-test. Results: MTA exhibited significant discoloration in contact with NaOCl (p < 0.05). White precipitation occurred on the surfaces of Biodentine and ERRM after contact with the solutions, and none of the materials presented dark brown discoloration. All materials showed significant solubility after immersion in the solutions (p < 0.05), irrespective of the solution type (p > 0.05). The surface topography and elemental composition of the samples showed different patterns of crystal formation and precipitation depending on the solution type. Conclusions: All materials presented some amount of solubility and showed crystal precipitation after contact with the solutions. Biodentine and ERRM are suitable alternatives to ProRoot MTA as they do not exhibit discoloration. The use of OCT can be considered safe for CSCs.