• Restorative Dentistry and Endodontics
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• 제10권1호
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• pp.17-30
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• 1984

This study was done to evaluate the hardness, water sorption and solubility values of twelve well known composite resins, and to compare each other. For the hardness test, the specimens were made in cylinder form with 4mm in diameter and 2mm in thickness as a modification of the American Society for Testing and New Materials, 1966, and for water sorption and solubility tests, the specimens were prepared in same shape of 20mm in diameter and 0.5mm in thickness as a modification of the ADA Specification No. 12. The results were obtained as follow: 1. The hardness range were from 17.9 to 87.5 respectively. As time passed by, the noticable change was evident in early 12 hours. 2. Of the water sorption. the range was from 0.38 to 0.93. The significant change was appeared within 12 hours and on 3 day by 1 week except four brands. 3. Of the water solubility, the range was 0.06 to 0.16. The highest value was found within early 24 hours. 4. Generally, four brands could be chosen as preferable products of hardness. water sorption and solubility tests according to the ADA Specification No. 12.

• 약학회지
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• 제35권5호
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• pp.372-378
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• 1991

To increase the stability and bioavailability of Omeprazole(OMP), which is used newly as a proton-pump inhibitor, inclusion complex of OMP with $\beta$-cyclodextrin($\beta$-CD) was prepared by coprecipitation method and its characteristics were ascertained by means of solubility test, DSC, IR, and the accelerated stability analysis. The type of OMP inclusion complex is classified as Bs-type on phase solubility diagram, and the stoichiometric ratio of OMP: $\beta$-CD complex is 1:2 and formation constant is 80.82/mole. The solubility of the complex could be increased remarkably by complexation compare with OMP. Degradation process of both OMP and OMP complex followed apparent first-order kinetics, of which degradation rate constants and activation energies are k$_{25}$=8.1$\times$10$^{-4}$/day, E$_{a}$=22 Kcal/mole (OMP), and k$_{25}$=4.65$\times$10$^{-6}$/day, E$_{a}$=35 Kcal/mole (complex), respectively. These results show the increase of the stability and solubility of OMP markedly, therefore it is believed that the improvement of stabilization for OMP by inclusion complexation might be practically available.

• Restorative Dentistry and Endodontics
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• 제39권3호
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• pp.201-209
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• 2014

Objectives: This study evaluated the solubility, dimensional alteration, pH, electrical conductivity, and radiopacity of root perforation sealer materials. Materials and Methods: For the pH test, the samples were immersed in distilled water for different periods of time. Then, the samples were retained in plastic recipients, and the electrical conductivity of the solution was measured. The solubility, dimensional alteration, and radiopacity properties were evaluated according to Specification No. 57 of the American National Standards Institute/American Dental Association (ANSI/ADA). Statistical analyses were carried out using analysis of variance (ANOVA) and Tukey's test at a significance level of 5%. When the sample distribution was not normal, a nonparametric ANOVA was performed with a Kruskal-Wallis test (${\alpha}$ = 0.05). Results: The results showed that white structural Portland cement (PC) had the highest solubility, while mineral trioxide aggregate (MTA)-based cements, ProRoot MTA (Dentsply-Tulsa Dental) and MTA BIO ($\hat{A}$ngelus Ind. Prod.), had the lowest values. MTA BIO showed the lowest dimensional alteration values and white PC presented the highest values. No differences among the tested materials were observed in the the pH and electrical conductivity analyses. Only the MTA-based cements met the ANSI/ADA recommendations regarding radiopacity, overcoming the three steps of the aluminum step wedge. Conclusions: On the basis of these results, we concluded that the values of solubility and dimensional alteration of the materials were in accordance with the ANSI/ADA specifications. PCs did not fulfill the ANSI/ADA requirements regarding radiopacity. No differences were observed among the materials with respect to the pH and electrical conductivity analyses.

• 한국식품과학회지
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• 제29권6호
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• pp.1089-1093
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• 1997

에리스리톨을 설당 대체 감미료 소채로 사용하기 위한 기초 자료를 얻기 위하여 흡습성, 용해도, 수분활성도, 열안정성, 점성과 같은 물성학적 특성을 설탕, 자일리톨, 소르비톨, 프럭토올리고당과 비교 측정하였다. 모든 감미료 중에서 에리스리톨은 가장 낮은 흡습성과 가장 큰 수분활성 저하능력을 나타내었고 $20^{\circ}C$에서 35.8% 용해되어 다른 감미료보다 용해도가 낮았다. 프럭토올리고당이 빠른 감미료들에 비해 현저히 열안정성이 낮았던 반면 에리스리톨의 열안정성은 오히려 설탕보다 컸다 10%, 30% 에리스리톨 용액의 점성은 동일 농도의 다른 감미료 용액의 점성과 비슷하였으나 고농도 50% 이상의 감미료 용액에서의 점도는 분자량이 증가할수록 점토가 증가하였다. 온도 증가에 따른 감미료들의 점성은 감소되었으며 Arrhenius equation으로 표현될 수 있었다. 30% 에리스리톨 용액과 30% 설탕 용액의 유동활성화에너지는 각각 10.8 kcal/g mol와 11.2 kcal/g mol이었다.

• 한국의류학회지
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• 제23권8호
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• pp.1161-1169
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• 1999

This research was aimed to identify the artifact type and their characteristics of the textile related materials excavated from Koryo Dynasty tombs of Hyungok-ni Danyang. Microscopy solubility test energy dispersive X-ray spectroscopy(EDS) and fourier transform infrared spectroscopy (FT-IR) fabric density test were used for the identification and when necessary standard samples were made in order to compare its characteristics with hose of the original artifact, the result indicated that the artifacts included both textile and paper. Artifacts from Burial 14 were comprised of textile fragments FT-IR and the solubility test conducted on the artifact indicated that the textiles were made with ramie woven with plain weave technique in a fairly loose fabric density. Rest of the artifacts were all comprised of paper.

• Journal of Pharmaceutical Investigation
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• 제40권6호
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• pp.339-345
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• 2010

Fenofibrate has been used for many years to lower cholesterol levels and its pharmacokinetic profile is well understood. However, due to its low solubility in water, it has low bioavailability after oral administration. In order to improve the dissolution rate, fenofibrate was formulated into a self-microemulsifying drug delivery systems (SMEDDS). We used pseudo-ternary phase diagrams to evaluate the area of microemulsification, and an in vitro dissolution test was used to investigate the dissolution rate of fenofibrate. The optimized formulation for in vitro dissolution assessment consisted of Lauroglycol FCC (60%), Solutol HS 15 (27%), and Transcutol-P (13%). The mean droplet size of the oil phase in the microemulsion formed from the SMEDDS was about 130 nm. The dissolution rate of fenofibrate from SMEDDS was significantly higher than that of the reference tablet. Our studies suggested that the fenofibrate containing SMEDDS composition can effectively increase the solubility and oral bioavailability of poorly water-soluble drugs.

• 한국전기전자재료학회논문지
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• 제28권5호
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• pp.314-319
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• 2015

In this research, we focused on the development of cy3 dye with high thermal stability and good solubility for LCD color filter. Cy3 dyes were prepared through the synthetic procedure of two steps. The synthesized cy3 dyes were characterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed maximum absorption wave length (${\lambda}_{max}$) in the range of 549~555 nm in UV/Vis spectrum. And we confirmed that solubility characteristics and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with methyl counter cation and ethyl counter cation have good solubility in organic solvents such as chloroform, ethanol, and PGME. Moreover, Cy3 dye with ethyl counter cation gave excellent thermal stability in TGA thermograms. And Cy3 dye with ethyl counter cation showed good result in photoresist film test.

• Fisheries and Aquatic Sciences
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• 제17권1호
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• pp.59-65
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• 2014

We measured the reductions in size and solubility of mackerel muscle that was freeze-dried, deoiled by supercritical carbon dioxide (SC-$CO_2$), or roasted. The percent size reduction and solubility were high in SC-$CO_2$-treated muscle compared with freeze-dried and roasted muscle. We used oil-free residues to test for heavy metals and determine microbial safety. The SC-$CO_2$, hexane, and ethanol were used to separate oil from muscle. The concentrations of cadmium (Cd) in all treated muscles were less than the values reported in the literature, as were the concentrations of lead in SC-$CO_2$- and hexane- treated muscle. In contrast, concentrations of arsenic and mercury in muscles were greater than the reported values regardless of treatment. Zinc and iron, which are beneficial for health, were found in high levels after all treatments of muscle tissue. After 6 months of storage at different temperatures, SC-$CO_2$-and ethanol-treated muscle showed few bacterial colonies, and none were found after 4 months of storage at $-20^{\circ}C$. These results will be useful to food-processing industries for maintaining high-quality, safe mackerel muscle.

• 한국산업보건학회지
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• 제24권2호
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• pp.146-151
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• 2014

Objectives: Chrysotile is mineralogically distinct from amphiboles, displaying a notably different chemical structure. The thin sheets that form chrysotile fiber lead to the ability of the lung/macrophage system to decompose the chrysotile fibers. This study was performed in order to compare the physicochemical characteristics of Korean asbestos with those of Canadian amphiboles. Materials: An acid solubility test for each test substance was done to compare pH 4.5 and pH 1.2 distilled water. Asbestos fibers which had been placed in acid solutions for five days, five weeks and weeks were analyzed with a transmission electron microscope equipped with an energy dispersive X-ray spectrometer (TEM-EDS). Results: The composition element (Mg) of Korean chrysotile, Korean anthophyllite and Canadian amosite significantly decreased from 5 days and also decreased significantly after 5 weeks and 10 weeks. Only the composition (Mg) of Canadian crocidolite did not change under any conditions. From 5 days, the Mg of Korean chrysotile, Korean anthophyllite and Canadian amosite were significantly lower than before the acid treatment, but there were no changes over time or by the pH of the acid solutions. Particularly after 10 weeks, the composition (Mg) of Korean chrysotile in the pH 1.2 acid solution showed a rapid reduction of 15.86%. Conclusions: Korean chrysotile was very weak in an acid environment, beginning to show significant changes after 5 days. The Mg component rapidly decreased after 10 weeks in the pH 1.2 acid solution.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.109-117
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• 2020

Cre recombinase is widely used to manipulate DNA sequences for both in vitro and in vivo research. Attachment of a trans-activator of transcription (TAT) sequence to Cre allows TAT-Cre to penetrate the cell membrane, and the addition of a nuclear localization signal (NLS) helps the enzyme to translocate into the nucleus. Since the yield of recombinant TAT-Cre is limited by formation of inclusion bodies, we hypothesized that the positively charged arginine-rich TAT sequence causes the inclusion body formation, whereas its neutralization by the addition of a negatively charged sequence improves solubility of the protein. To prove this, we neutralized the positively charged TAT sequence by proximally attaching a negatively charged poly-glutamate (E12) sequence. We found that the E12 tag improved the solubility and yield of E12-TAT-NLS-Cre (E12-TAT-Cre) compared with those of TAT-NLS-Cre (TAT-Cre) when expressed in E. coli. Furthermore, the growth of cells expressing E12-TAT-Cre was increased compared with that of the cells expressing TAT-Cre. Efficacy of the purified TAT-Cre was confirmed by a recombination test on a floxed plasmid in a cell-free system and 293 FT cells. Taken together, our results suggest that attachment of the E12 sequence to TAT-Cre improves its solubility during expression in E. coli (possibly by neutralizing the ionic-charge effects of the TAT sequence) and consequently increases the yield. This method can be applied to the production of transducible proteins for research and therapeutic purposes.