• Journal of Korea Foundry Society
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• v.31 no.4
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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.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.323-327
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• 2014

To analyze the characteristics of bacteriophages in Enterococcus faecium, D-19 and F6 phages were induced from five E. faecium isolated from sprouts by the treatment with mitomycin C. The bacteriophages of D-19 and F-6 had long, non-contractile tails and icosahedral heads, and were members of Siphoviridae family. As the host spectrum, D-19 phage lysed five out of 55 strains of E. faecium, whereas F6 phage lysed only three strains. Both D-19 and F6 phages displayed similar and high stabilities against ethanol and pH capable of resisting the exposure to 100% ethanol and pH 4.

• Membrane Journal
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• v.32 no.6
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• pp.383-389
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• 2022

Membrane separation process is an important technique utilized for various applications. This separation process proceeds due to a driving force such as concentration gradient, pressure or electrical potential gradient etc. Pervaporation is one of the separation process based on solution-diffusion mechanism. The pressure of the permeate side is reduced by creating vacuum and separation is driven due to pressure difference. Purity of the fuel or chemical like ethanol or isopropyl alcohol are improved by dehydration process through porous zeolite membrane. These membranes have high thermal, chemical, mechanical stability. This review is classified mainly into two different sections: Ethanol and bio-oil dehydration by zeolite membrane.

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.207-215
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• 2012

Phenolic compounds of $17.9{\pm}1.0mg/g$ were extracted from Ulmus pumila with 70% ethanol. The elastase inhibitory activity related with forming wrinkle was shown an excellent wrinkle improvement effect in 70% ethanol extracts as 55.5-69.5% at phenolic concentration of $50-200{\mu}g/mL$. The tyrosinase inhibitory activity related with skin-whitening was 24% in 70% ethanol extracts at phenolic concentration of $200{\mu}g/mL$. The astringent activity of 70% ethanol extracts was shown activity of 71% at phenolic concentration of $200{\mu}g/mL$ therefore it is judged that there is a high effect on pores reduction of the skin. The hyaluronidase inhibitory activity of U. pumila extracts was confirmed anti-inflammation effect of 80% at phenolic concentration of $50{\mu}g/mL$. Antimicrobial activity of U. pumila water extracts was shown each 8.7, 10.0, 11.1 and 11.8 mm clear zones on Propionebacterium acnes at phenolic concentration of $50-200{\mu}g/mL$. The stability of the multi-functional cosmetic (lotion) added U. pumila extracts was very stable for 28 days without changing of pH and viscosity also it's stable on temperature and sun lights. As the concentration of extracts was increased, the color of lotion was getting dark, but the sensory evaluation was high at score of 8.5.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.5
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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.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.445-449
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• 2003

As for the purpose, we first introduce an random mutation into wild-type gene to expand a mutation space, and then further recombine the mutant genes by staggered extension process PCR. As a result, we obtained the best clones 6-52 that showed a high activity and stability, from a round of error prone and staggered extension process PCR. The purified enzyme showed a similar pH stability to the wild-type enzyme and reveal a slightly high optimum pH at 12. In the optimum temperature, an identical dependency was also showed and a quite high stability in the thermal stability was obtained. Along with this, the enzyme was also stable at a reaction that supplement with a 15 % of ethanol as an additive. The addition of other solvents and surfactants did not improve the reaction and thus resulted in a similar profile to those of wild-type enzyme. The specific activity on the target compound rac-ketoprofen ethyl ester was calculated to be about 85, 000 unit, and the kinetic constants Km and Vmax were determined to be 0.2 mM and 90 mM/mg-protein/min respectively. The deduced amino acid alignment with the wild type enzyme revealed five mutations at L120P, I208V, T249A, D287H and T357A. Based on these observations, the site directed mutagenesis to delineate the mutagenic effect is under progress.

• Korean Journal of Materials Research
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• v.13 no.11
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• pp.725-731
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• 2003

The effect of organic processing parameters on the dispersion stability of the BaTiO$_3$-based dielectric particles and borosilicate glass particulate suspensions was investigated in a system where organic solvents, dispersant, binder and modifier were used as processing additives in a low temperature cofired ceramic fabrication processes. Two- and three-component organic solvents were used to disperse ceramic particles and it was found the better stability in the particulate suspension prepared in a bi-solvent, which was consists of toluene and ethanol in a non-azeotropic composition. The addition amount of organic additives had a great impact on dispersion in the present investigation. The flow curves of the suspensions prepared with binder and modifier were fitted according to the power-law equation, which indicates that the internal structure of the suspension could be disturbed under the applied shear stress. Finally, the LTCC green tapes were successfully tape-cast based upon the optimum formulation of LTCC suspension and its microstructure was compared with that of the hard-agglomerates.

• Journal of the Korean Applied Science and Technology
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• v.14 no.1
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• pp.45-52
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• 1997

It is the problem point of stability for this study to produce cosmetics and to occur in the circulation process, and specially in a case of alcoholic toilet water the precipitation materials to float on content materials has study on the solubility of perfume, and it has practiced in order to examine the problem point whether the raw materials of plastic vessel is or not harmful in content materials. In testing result, A study on stability of alcoholic toilet water is above all the precipitation materials which floats in content materials, and It is appeared by combination ratio to the raw materials of perfume, ethanol, solubilizer and refining water etcs, and in second the alkali degree which has gushed out of glass vessel can understand the thing that the change of PH is largely increased following to the passage of time, and in third the harmful component of content materials out of raw material in plastics vessel must certainly consider a stability and a safety in quality control of products.

• KSBB Journal
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• v.25 no.6
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• pp.513-519
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• 2010

Marine bacterium producing pigment was isolated from the solar saltern of Mijo-myeon, Namhae, Korea. Based on phenotypic characteristics and 16S rRNA sequence analysis, the strain was identified as Kocuria sp., which produced a yellow pigment. The pigment showed UV absorption maximum at 469nm. The bacterial strain grew well on Marine broth 2216 culture medium. Productivity of the pigment reached the maximum value after 44 hours at $30^{\circ}C$, 2% NaCl and pH 6.0. The pigment was produced best when supplied by 1% lactose as a carbon source and 1% beef extract as a nitrogen source. The result of the color stability study showed that pigment extracted from the strain by ethanol was stable at $-20-25^{\circ}C$ and also showed higher stability over 70% for 14 days in light conditions at $25^{\circ}C$. The pigment extract was also stable for all metal ions tested, except for $FeCl_2$.

• Journal of Apiculture
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• v.34 no.4
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• pp.325-328
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• 2019

We investigated the food storage stability of propolis extracts using homemade meatballs. Propolis extracts were prepared by using the ethanol extraction method. After making the meatballs, propolis was mixed into the meatball materials and egg water with a final concentration of 1% v/v. Microbial cultivation results showed that the cultivation of Staphylococcus aureus, which is one of the food poisoning bacteria, was reduced by more than 90% and the period of storage was 1.5 times longer. Also, it was observed to be effective when propolis was added to meatballs, it was even more effective when propolis was mixed with egg water. Thus, propolis extracts may be a useful ingredient for food storage stability due to its anti-microbacterial function.