• Microbiology and Biotechnology Letters
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• v.3 no.2
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• pp.63-68
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• 1975

A biological active substance was isolated from the cultured medium of Streptomyces sp. and its biochemical characteristics were investigated. Isolation process of the substance was as follows; the pH of filterate of the cultured medium was adjusted to 3.0 with N-hydrochloric acid and saturated with sodium chloride, then chloroform was added to this filterate in one fifth portions and stirred vigorously. After extracting the active substance with chloroform in 3 stages, the chloroform layer combined and evaporatea after dehydrating with sodium sulfate. The substance was found to be to be toxic to various fresh water fishes; the lethal dose for an average size Pseudorasbora parva T. et. S. was 50ug per ml. In the acidic condition, the toxicity of the substance remained fora long time, while in the alkaline state, the toxicity was decreased very fast. This substance was found to be stable to organic solvents, but labile to heat treatment. The maximal revival time of Pseudorasbora parva T. et. S. was about 20 minutes in 25 ug/ml of the substance solution.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.1-9
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• 2020

This study conducted to understand effects of CA (CaAl₂O₄) and CA₂ (CaAl₄O₇) ratio on chloride binding ability and compressive strength and pore structure of cement mortar incorporating mixture of CA and CA₂. The Portland cement based specimens were mixed with the clinkers CA and CA₂, and these calcium aluminate clinker mixture were replaced 0, 5, 10% by weight of cement. After all the test specimens were cured for 28 days under water curing, they were immersed in the distilled water and NaCl solution. As a result, 28 days compressive strength of all specimens was similar, and As the replacement ratio of calcium aluminate clinker in the specimen increased, Friedel's salt production tended to increase. However, it was dependent on the amount of Al₂O₃ in the level of 5% replacement and CA ratio in the level of 10% replacement. Through equilibrium isotherm result, it was also indicated that as replacement ratio of calcium aluminate clinker in cement matrix increased, chloride binding capacity was improved, and chloride penetration was suppressed. In this study, the specimen replaced with 10% of the calcium aluminate clinker mixture (CA 39%, CA₂ 60%) was remarkable to control chloride attack. We figured out necessity to understand optimal CA/CA₂ ratio to effectively apply CA₂ as a sustainable building material by improving the chloride binding ability in Portland cement based system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.211-215
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• 2002

Pretense production and its characteristics were investigated for Rhizopus stolonifer, Rhizopus oryzae and Absidia corymbifera which were isolated from Korean traditional meju. The optimum culture conditions of the strains for the production of protease in basic medium [wheat bran : 1% glucose solution=1 : 1 (w/v)] were 3$0^{\circ}C$ and 4 days. The optimum pH and temperature for the enzyme activity of crude enzymes produced by Rhizopus sto-lonifer, Rhizopus oryzae and Absidia corymbifera were pH 6.0 and 5$0^{\circ}C$, respectively. The enzymes were relatively stable at pH 4.0~7.0, at temperature below 4$0^{\circ}C$, and at NaCl concentration lower than 16%. The $K_{m}$ value for Hammastein casein was 3.3$\times$10$^{-4}$ , 0.75$\times$10$^{-4}$ and 1.3$\times$10$^{-4}$ M, and $V_{max}$ value was 17.2$\mu\textrm{g}$/min, 9.4$\mu\textrm{g}$/min and 7.8$\mu\textrm{g}$/min, respectively.y.

• KSBB Journal
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• v.17 no.1
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• pp.100-105
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• 2002

N-acetyl-D-glucosamine oligosaccharides [(GlcNAc)n] whose degree of polymer-ization is from one to ten (n=1-10) were fractionated by column chromatography on CM-Sephadex. Electro dialysis from a partially deacetylated chitosan hydrolysate prepared crudely with the N-acetyl-D-glucosaminidase(chitinase) and exo-N, N'-diacetylchito-biohydrolase(chitobiase) of Serratia marcescens QM B1466. Reducing sugar compositions and sequences of the N-acetyl-glucosamine oligosaccharides were identified by N-acetylation, randomly cleavage with chitinase and ego-splitting with chitobiase. N-acetyl-glucosamine heterochitooligosaccharides with glucosamine oligosaccharides, (GlcN)n at the reducing end residues together with $(GlcN)_1\sim(GlcN)_4$ were detected. Separation was accomplished by prefractionation with election by 0 to 1.0 M NaCl gradient solution. $(GlcNAc)_1 =4.25%,\; (GlcNAc)_2=4.49%,; (GlcNAc)_3=11.1%,\; (GlcNAc)_4=2.5%,$$ $(GlcNAc)_{5}$=0.64%, $(GlcNAc)_{6}$=2.12% and $(GlcNAc)_{7}$=1.21%, respectively, were crystallized after electrodialysis and lyophilization Each N-acetyl-D-glucosamine oligosaccharides content were detected by HPLC.

• Clean Technology
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• v.18 no.4
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• pp.446-450
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• 2012

Strong alkaline electrolyzed water which is produced in cathode by electrolyzing the solution where electrolytes (NaCl, $K_2CO_3$ etc.) are added in diaphragm electrolytic cell, is eco-friendly and has cleaning effects. So, it is viewed as a substitution of chemical cleaner. In addition, strong alkaline electrolyzed water is being used by some Japanese automobile and precision parts manufacturing industries. When strong alkaline electrolyzed water is produced by using diaphragm electrolytic cell, it is necessarily produced at the anode side. Since strong acidic electrolyzed water produced is discarded when its utilization cannot be found, production efficiency of electrolyzed water is consequently decreased. Also, there is a weakness electrolytic efficiency is decreasing due to the pollution of diaphragm. In order to overcome this, non-diaphragm all-in-one electrolytic cell integrated with electrode reaction chamber and dilution chamber was applied. Strong alkaline electrolyzed water was produced for different composition of electrolytes, and their properties and characteristics were identified. In comparing the properties between strong alkaline electrolyzed water produced in diaphragm electrolytic cell and that produced in all-in-one electrolytic cell, the differences in ORP and chlorine concentration were found. In emulsification test to confirm surface-active capability, similar results were obtained and strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell was identified to be useable as a cleaner like strong alkaline electrolyzed water produced in diaphragm electrolytic cell. Strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell is thought to have sterilizing power because it has active chlorine which is different from strong alkaline electrolyzed water produced in diaphragm electrolytic cell.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.9-16
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• 2000

Aroma of various extracts of Agastache rugosa O. Kuntze was analyzed by electronic nose with 32 conducting polymer sensor arrays. The 57 extracts were prepared by extraction solvents (hot water, ethanol and NaCl solution), extraction temperatures $(100,\;80\;and\;60^{\circ}C)$, solvent mixture ratios of solvent (10 times 35 times) and parts of Agastache rugosa O. Kuntze(flower, leaf and stem). Aroma pattern of Agastache rugosa O. Kuntze extracts showed big difference in normalized pattern and odor intensity with extraction temperatures and parts, but showed no difference with extraction solvents. Especially in the case of ethanol extracts, because odor of ethanol itself was very strong, difference in aroma of extracts with extraction temperatures and parts did not show through the electronic nose. The organoleptic characteristics such as mint odor, grassy odor, mint taste, medicinal herb taste and sweetness for Agastache rugosa O. Kuntze extracts were determined by the profile test and the result of sensory evaluation by quantitative descriptive analysis was explained to QDA diagram. In correlation with the result of aroma analysis by electronic nose and the sensory evaluation, difference in aroma pattern among the extracts concretely brought to light definite characteristics such as mint odor and mint taste.

• Journal of the Korean Society for Railway
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• v.11 no.4
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• pp.357-363
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• 2008

This study investigates the durability of carbon/epoxy composites for use on train car bodies under a salt water spray environment. Salt water solution with 5% NaCl, similar to natural salt water, was used for the salt water environmental tests. The specimens were obtained from a composite panel consisting of an epoxy matrix reinforced with T700 carbon fabric. The specimens were exposed to the salt water environment for up to 12 months. Mechanical tests were performed to obtain tensile properties, flexural properties, and shear properties. Dynamic mechanical analysis was used to measure such thermal properties as storage modulus, loss modulus, and tan $\delta$. Also FT/IR tests were conducted to investigate changes in chemical structure with exposure. The results revealed that fiber-dominated mechanical properties were not affected much by exposure time, but matrix-dominated mechanical properties decreased with increasing exposure time. Storage modulus was not very sensitive to exposure time, but glass transition temperature was affected, slightly decreasing with increasing exposure time. Although the peak intensity of FT/IR curves was affected slightly by exposure time, the peak shape and peak location of FT/IR curves were not noticeably changed. Carbon/epoxy composites used for this study were relatively stable to the salt water environment.

• Journal of Conservation Science
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• v.28 no.4
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• pp.329-341
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• 2012

Magai Wareiishi Jizo (Buddhist statue carved on rock surface) is close to shoreline and a part of rock block is periodically immersed by seawater. Rock material of the Wareiishi-jizo statue is composed mainly of medium or coarse-grained biotite granite and very durable. However, physical properties of the rock have been changed according to the complex interactions of the salt solution and surrounding environment. Exfoliation of the rock surface is a serious condition by salt crystallization. Exfoliation (14.6%) is concentrated on the upper part of the rock block with mainly boundary of seawater as the center. On the other hand, lower part of the rock block show black layers by contaminants deposition. In addition, brown discoloration and biological contaminants is overlapped. Rock surface show high discoloration rate of 50.5% (black discoloration, 29.2% > yellow discoloration, 14.1% > brown discoloration, 4.4% > green discoloration, 2.9%). Upper part of the rock block had a lot of change in the physical properties than lower part that is immersed by seawater. In particular, surface properties of the rock block was very weak state at the boundary surface of seawater permeation.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.398-402
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• 1996

This study was carried out to compare the fermentation rates of Dongchimi as affected by fermentation temperature and salt concentration of brining solution. The Dongchimi was prepared by fermentation of the radish in salt solutions of 2.0, 3.2 and 5.1% NaCl respectively with addition of garlic, green onion, ginger at $4^{\circ}C,\;10^{\circ}C,\;20^{\circ}C$. The fermentation was classified into 3 steps of initial, intermediate and final stages according to pH changes and the rates of fermentation and color change were calculated from intermediate stage. The time reached equilibrium in hardness of radish and salt concentration and their equilibrated values were also compared. Fermentation rate became more rapid as fermentation temperature and salt concentration increased. The rates of Hunter color change of Dongchimi liquid were increased as the temperature increased. The 'L' values decreased slowly, and 'a' and 'b' values increased rapidly to maximum at the intermediate stage. The time required to reach equilibrium was reduced for both salt concentration and hardness of radish as the fermentation temperature increased. The equilibrated values of salt concentration were increased while those of hardness of radish were decreased as the temperature and salt concentration increased. The data obtained can be used for prediction of some of the major characteristics of Dongchimi during fermentation.

• Korean Journal of Oriental Medicine
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• v.15 no.3
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• pp.83-91
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• 2009

$\beta$-glucan is a fiber-type complex sugar (polysaccharide) derived from the cell wall of baker's yeast, oat and barley fiber, and many medicinal mushrooms, such as maitake. The primary uses of $\beta$-glucan are to enhance the immune system, to lower blood cholesterol levels and to treat tumor. $\beta$-glucan has no systemic toxicity in mice, therefore it needed clinical trail to prove efficacy and safety for human. The subjects total 56 healty volunteers were divided into two groups including taken $\beta$-glucan tablet group and placebo group. Subjects were taken two tablets per oral for 4 weeks. They had agreed to take part in this experiment, and didn't take any other clinical trail products. After 4 weeks blood of subjects were checked. The check list are TNF-$\alpha$, INF-$\gamma$, IL-2, IL-4, total WBC, differential WBC, RBC, hemoglobin, platelet, MCV, MCH, MCHC, HCT, Na, K, Ca, Cl, AST, ALT, ALP, $\gamma$-GTP, total protein, triglyceride, total cholesterol, total bilirubin, albumin, uric acid, creatinine, BUN, pH, protein, glucose, ketone body, blood, bilirubin. We evaluated efficacy by cytokines that compare before and after taking. Collected data were analyzed as two sample t-test, chi-square test and ANOVA using SAS V.9.1.This study results are that in TNF-$\alpha$ of $1^{st}$ efficacy measurement item, all of two groups figure were increased significantly compare to before figure. In IL4 of $2^{nd}$ efficacy measurement item, experimental group figure were decreased significantly but placebo group figure were increased. The conclusions show that based on the above results, $\beta$-glucan has favorable effect to enhance immune system, especially IL4 results showed that it has effect to improve the allergic immune system.