• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.558-563
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• 1999

Response surface methodology was used for monitoring physicochemical properties of chitosan with preparation of chitosan. Deacetylation degree of chitosan was in proportion to NaOH concentration for deacetylation of chitosan. The solubility of chitosan was maximized in 52% (concentration of NaOH), $109^{\circ}C$ (deacetylation temperature) and 123 min (deacetylation time). Viscosity of chitosan was mainly influenced by concentration of NaOH, and was greatly decreased with the increase of concentration of NaOH. The optimum condition ranges for preparation of chitosan was $52{\sim}54%$ NaOH, $100{\sim}115^{\circ}C$ in deacetylation temperature and $100{\sim}140\;min$ in deacetylation time.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.720-725
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• 2000

To reduce the antigenicity of egg white (EW), EW was treated with several proteolytic enzymes, trifluoromethanesulfonic acid (TFMS), heat, and NaOH. Competitive indirect enzyme-linked immunosorbent assay (ciELISA), using rabbit anti-EW antibody, was performed to examine the antigenicity of the treated EW's. Enzymatic hydrolysis gave no good effect on the reduction of the antigenicity of EW. Neither did the pretreatment with ${\gamma}-irradiation$ before the hydrolysis reduce the antigenicity. TFMS treatment removed the antigenicity of EW. The antigenicity of EW heated at $120^{\circ}C$ for 30 min or treated with NaOH at 0.3% (w/v) and more, decreased to less than 1/10,000 as compared with that of native EW. The combinatory treatment with NaOH, followed by heat at $70^{\circ}C$ for 15 min had a synergic effect on the reduction of the antigenicity of EW.

• Clean Technology
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• v.13 no.3
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• pp.201-207
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• 2007

Carboxymethylcellulose (CMC), which is water-soluble at room temperature, was synthesized from cellulose in this study. Experimental parameters included reaction temperature, time, concentration of NaOH, and monochloroacetic acid (MCA). In mercerization and etherification, solubility and degree of substitution (DS) increased when NaOH (or MCA) concentration increased and maximum solubility and DS were achieved when NaOH or MCA was 30%. The effect of MCA concentrations on the DS was larger than that of the NaOH concentration. Tensile strength of the CMC was decreased by the increases of reaction time, reagent concentration and reaction temperature. Tensile strength also decreased by NaOH and MCA. However, low decrease of tensile strength was observed in near neutral region.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.442-451
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• 1999

This study was conducted to investigate the antimicrobial activity of Prunus mume extracts. Prunus mume extracts have growth inhibitory activity to various microorganisms. Gram positive bacteria such as Bacillus cereus, Bacillus subtilis, Micrococcus leteus, Staphylococcus epidrimidis were more easily inhibited than Gram negative bacteria tested Vibrio parahaemolyticus, Salmonella typhimurium, Escherichia coli, Proteus vulgaris and Yeasts by Prunus mume extracts. Among several fractions of methanol extract, EtOAc & BuOH fractions were showed strong antibacterial activities, but those fractions were not showed on fungi.

• Proceedings of the Culinary Society of Korean Academy Conference
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• 2001.08a
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• pp.29-41
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• 2001

This study was conducted to investigate the antimicrobial activity of Prunus mume extracts. Prunus mume extracts have growth inhibitory activity to various microorganisms. Gram positive bacteria such as Bacillus cereus, Bacillus subtilis, Micrococcus leteus, Staphylococcus epidrimidis were more easily inhibited than Gram negative bacteria tested Vibrio parahaemolyticus, Salmonella typhimurium, Escherichia coli, Proteus vulgaris and Yeasts by Prunus mume extracts. Among several fractions of methanol extract, EtOAc & BuOH fractions were showed strong antibacterial activities, but those fractions were not showed on fungi.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.40-47
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• 2014

In this paper, $Al_2O_3$ film deposited by thermal atomic layer deposition (ALD) with diluted $NH_4OH$ instead of $H_2O$ was suggested for passivation layer and anti-reflection (AR) coating of the p-type crystalline Si (c-Si) solar cell application. It was confirmed that the deposition rate and refractive index of $Al_2O_3$ film was proportional to the $NH_4OH$ concentration. $Al_2O_3$ film deposited with 5 % $NH_4OH$ has the greatest negative fixed oxide charge density ($Q_f$), which can be explained by aluminum vacancies ($V_{Al}$) or oxygen interstitials ($O_i$) under O-rich condition. $Al_2O_3$ film deposited with $NH_4OH$ 5 % condition also shows lower interface trap density ($D_{it}$) distribution than those of other conditions. At $NH_4OH$ 5 % condition, moreover, $Al_2O_3$ film shows the highest excess carrier lifetime (${\tau}_{PCD}$) and the lowest surface recombination velocity ($S_{eff}$), which are linked with its passivation properties. The proposed $Al_2O_3$ film deposited with diluted $NH_4OH$ is very promising for passivation layer and AR coating of the p-type c-Si solar cell.

• Analytical Science and Technology
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• v.14 no.6
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• pp.522-529
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• 2001

Carbon monoxide was generated when the saccharides which contained aldehyde group were added to alkali solution (NaOH solution) at $25^{\circ}C$ or $40^{\circ}C$. When the milk was added to 1.0 M NaOH solution at $25^{\circ}C$ and to 0.01 M NaOH solution at $40^{\circ}C$, carbon monoxide was generated. The carbon monoxide gas which was generated by 20 mL of 0.1 M lactose or 0.1 M xylose and 2 mL of 1.0 M NaOH solution at $50^{\circ}C$ for 2days was bubbled through 2 mL of fresh blood. The carboxyhemoglobin concentrations of both conditions were 31%. However, when the carbon monoxide gas which was generated by 30 mL of milk and 2 mL of 1.0 M NaOH at $50^{\circ}C$ for 2days or 3days was bubbled through 2 mL of fresh blood, the carboxyhemoglobin concentration was 32% or 42% respectively.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.496-501
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• 1995

Experiments were carried out to find out the optimal condition of SCP produced by Cellulomonas sp. KL-6 and to evaluate nutritional value for the protein of this organism Intracellular- and extracellular proteins produced by this strain were estimated to be nearly maximum, $266\;{\mu}g/m{\ell}\;and\;37\;{\mu}g/m{\ell}$, in the medium containing 0.001% of thiamin after 5 days cultivation. When used rice straw as carbon source for the cell growth of this organism after crusing them by cutting mill, and treating them with 1.0% of NaOH and 10.0% of $NH_4OH\;at\;80^{\circ}C$ for 30 minutes and neutralizing continuatively them with 85% of $H_3PO_4$, SCP production rates were very increased to $1.63\;g/{\ell}$ (NaOH) and $1.47\;g/{\ell}$ (NH4OH), respectively than $0.5\;g/{\ell}$ produced in untreated rice straw. We compared their amino acids patterns with that of FAO provisional patterns. Amino acids content of strain KL-6 was excellents. However. when intended these cell mass to use in practical animal feeding test it would be advisable that destruction or lysis of cell wall should be done.

• The Korean Journal of Food And Nutrition
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• v.32 no.3
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• pp.208-215
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• 2019

In this paper, we investigate to determine quality characteristics, fatty acid composition and cytotoxic effect of extracts and fractions from whole Lycopus lucidus Turcz. roots. Additionally, we evaluated cytotoxic activity against the growth of human fibrosarcoma cells (HT-1080) and human gastric adenocarcinoma (AGS), human colon cancer cell (HT-29) lines using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Acetone+methylene chloride (A+M) and methanol (MeOH) extracts from L. lucidus Turcz. were obtained through solvent extraction. Then we further fractionated both extracts with n-hexane, 85% aq. MeOH, n-butanol (n-BuOH) and water. In fatty acid composition, L. lucidus Turcz. contained 33.2% of 18:1n-9 and 1.81% of 18:3n-3, respectively. The incorporation of treatment with A+M and MeOH extracts and n-hexane, 85% aq. MeOH, n-butanol (n-BuOH) and water fractions dose-dependently increased cytotoxicity against the growth of HT-1080 and AGS, HT-29 cancer cells (p<0.05). The A+M extract had a higher inhibitory effect on the growth of all cancer cells in comparison to MeOH extract. Among the fractions, the 85% aq. MeOH and n-hexane fractions showed a higher inhibitory effect after proliferating the three cancer cells. These results suggest that the 85% aq. MeOH and n-hexane fractions have a potential to inhibit the growth of human cancer cell lines.

• Journal of Powder Materials
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• v.26 no.3
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• pp.231-236
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• 2019

Ni hydroxides ($Ni(OH)_2$) are synthesized on Ni foam by varying the hexamethylenetetramine (HMT) concentration using an electrodeposition process for pseudocapacitor (PC) applications. In addition, the effects of HMT concentration on the $Ni(OH)_2$ structure and the electrochemical properties of the PCs are investigated. HMT is the source of amine-based $OH^-$ in the solution; thus, the growth rate and morphological structure of $Ni(OH)_2$ are influenced by HMT concentration. When $Ni(OH)_2$ is electrodeposited at a constant voltage mode of -0.85 V vs. Ag/AgCl, the cathodic current and the number of nucleations are significantly reduced with increasing concentration of HMT from 0 to 10 mM. Therefore, $Ni(OH)_2$ is sparsely formed on the Ni foam with increasing HMT concentration, showing a layered double-hydroxide structure. However, loosely packed $Ni(OH)_2$ grains that are spread on Ni foam maintain a much greater surface area for reaction and result in the effective utilization of the electrode material due to the steric hindrance effect. It is suggested that the $Ni(OH)_2$ electrodes with HMT concentration of 7.5 mM have the maximum specific capacitance (1023 F/g), which is attributed to the facile electrolyte penetration and fast proton exchange via optimized surface areas.