• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.637-642
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• 2017

In this study, cold flow and combustion tests are conducted and analyzed to validate designed rocket engine head generating high temperature/pressure steam. At first, uni-injector was designed and manufactured, and cold flow test was conducted. Through this, differential pressure that can supply designed flow rate was confirmed. Also, Each injector's spray pattern were confirmed by patternator. Based on cold flow test results, we selected injectors among the candidates and arranged them on engine head, and cold flow and propellant spray tests were conducted. Finally, combustion test was carried out to analyze the flow rate, pressure, combustion efficiency. As a result, validation of rocket engine head for the development of the high temperature and high pressure steam generator has been completed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.363-367
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• 1983

Low salt fermented products of anchovy, Engraulis japonica, caught in the coasts of East Sea of Korea, were prepared tentatively and also discussed the retarding effect of rancidity of the product by the addition of BHA or red pepper. Fresh anchovies were purchased from Kichang fish market. The raw samples were mixed with $8\%$ table salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper and filled in the glass bottles and sealed with the cap. Conventional fermented product of anchovy as a control was prepared from fresh anchovy and $20\%$ salt only. After preparation, the products were fermented for 90 days at room temperature. Amino-nitrogen, TBA value, peroxide value and viable counts of bacteria of these products were determined and also evaluation of their qualify was compared with control product by sensory evaluation during fermentation. Amino-nitrogen contents of the low salt products reached a peak in 55 days of fermentation, and the volatile basic nitrogen contents ranged $100\;mg\%$ even after 90 days of fermentation. Thiobarbituric acid value of the product with $0.02\%$ BHA showed a little increase up to 65 days of fermentation regardless of salt contents, while that of the control product increased sharply up to 65 days and then decreased gradually. BHA was effective on retarding rancidity of fermented products of anchovy and red pepper was also slightly effective. All the products showed the highest cell population in about 55 days of fermentation. Judging from the results of analysis and sensory evaluation, the low salt fermented product of anchovy could be prepared with $8\%$ salt, $0.5\%$ lactic acid, $6\%$ sorbitol, $4\%$ ethyl alcohol and $0.02\%$ BHA or $0.5\%$ red pepper to the fresh round anchovy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.312-320
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• 1986

The taste compounds in low salted and fermented damsel fish, Chromis notatus, substitute lactic acid, sorbitol and ethyl alcohol for sodium chloride and fatty acid composition were analysed during fermentation. The best organoleptic result was obtained after 60 days fermentation. Volatile basic nitrogen (VBN) was increased significantly until 10 days fermentation period but low salted and fermented products ($8\%\;and\;10\%$ salted) gave lower VBN value than that of $20\%$ salted after 85 days fermentation. Amino nitrogen also increased rapidly after 10 days fermentation and slowed down up to 60 days but it was decreased after 85 days. The abundant amino acids in raw damsel fish were lysine, taurine, aspartic acid, glutamic acid, proline and alanine and those were consisted of $58.8\%$ of the total free amino acids but arginine and tyrosine were trace in content. After 60 days fermentation, lysine, glutamic acid, alanine, leucine, aspartic acid and valine were dominant which marked $58{\sim}71\%$ of the total free amino acids but taurine was not detected. In raw ingredients, IMP was abundant which marked $18.6{\mu}mole/g$ while in fermented sample, hypoxanthine was predominant but ATP and ADP were not detected. During fermentation TMA was increased but TMAO was decreased which marked only trace after 60 days. Total creatinine was rapidly increased after 10 days but notable change was not showed after 60 days fermentation. The major fatty acids of total lipid in raw and fermented damsel fish were 16:0, 18:1, 16:1, 22:6 and 20:5 in order.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.597-606
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• 2015

This work investigates the carbonation of KOH-dissolved methanol and ethanol solution systems carried out for $CO_2$ fixation. Potassium methyl carbonate (PMC) and potassium ethyl carbonate (PEC) were synthesized during the reaction in each solution as the solid powder, and they were characterized in detail. The amount of $CO_2$ chemically absorbed to produce the PMC and PEC precipitates were calculated to be 97.90% and 99.58% of their theoretical values, respectively. In addition, a substantial amount of $CO_2$ was physically absorbed in the solution during the carbonation. PMC precipitates were consisted of the pure PMC and $KHCO_3$ with the weight ratio of 5:5, respectively. PEC precipitates were also mixture of the pure PEC and $KHCO_3$ with the weight ratio of 8:2, respectively. When these two precipitates were dissolved in excess water, methanol and ethanol were regenerated remaining solid $KHCO_3$ in the solutions. Therefore, the process has the potential to be one of the efficient options of CCS and CCU technologies.

• Journal of the Korean Chemical Society
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• v.9 no.2
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• pp.88-95
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• 1965

The exo adduct between furfuryl derivatives (furan, furfuryl acetate and furfuryl alcohol) and maleic anhydride were prepared in the presence of ethyl ether. The bromination of the exo adduct of each derivatives gave a monobromolactone and dibromoacid when the reaction was done in the presence of water. The formation of the bromolactone was proved to be dependent to the carboxylic participation to the incipient rearranged carbonium ion of a classical type, and the participation was sterically hindered by the steric structure of the substituents. The bromination of the furan-maleic anhydride adduct in the presence of organic solvent $(CCl_4,\;CH_2Cl_2)$ gave the dibromide, whereas the photochlorination of the same adduct in the presence of carbon tetrachloride gave the tetrachloride. The procedure of the preparation and the reaction path of the halogenation were described.

• Food Science and Preservation
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• v.21 no.6
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• pp.917-924
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• 2014

Normal- and late-harvested Fuji apples were fermented using the rapid-fermenting yeast strain Saccharomyces cerevisiae SS89. The late-harvest apples showed a slightly higher soluble-solid content with a lower level of total-acid and moisture (p<0.05) contents as well as hardness (p<0.05) than the normal-harvest apples. During the fermentation, the apples had similar changes in the pH and total-acid content regardless of the harvest time, but the increases in the alcohol content and yeast viable count with the decrease of the soluble-solid content were more rapid in the late-harvest apples than in the normal-harvest apples. After the completion of the fermentation, the soluble-solid and alcohol contents became very similar. The late-harvest cider showed a high total phenolic-compound content and a high DPPH radical scavenging effect, although these were slightly lower than those of the normal-harvest cider. It also showed a higher malic-acid content and higher hue color (p<0.05), Hunter's L, and b (p<0.05) values than the normal-harvest cider. In the sensory evaluation, the late-harvest cider obtained a higher score in taste and a lower score in color compared to the normal-harvest cider.

• Food Science and Preservation
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• v.21 no.5
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• pp.757-765
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• 2014

Campbell Early grapes were spontaneously fermented with and without sulfiting to investigate the effect of sulfiting on the fermentation characteristics and physicochemical properties of Campbell Early wine. During the fermentation, the increase in the alcohol and the decrease in the soluble solid contents were faster without sulfiting, as was the increase in the yeast viable counts compared to those with sulfiting. However, the final alcohol and soluble solid contents reached similar levels with and without sulfiting. The PCR-RFLP analysis of the yeast in the ITS I-5.8S-ITS II region revealed that the increase in the S. cerevisiae was faster in the initial fermentation stage and reached a slightly higher level in the late stage with sulfiting than without sulfiting. The wine prepared after the fermentation with sulfiting showed higher malic and tartaric acid contents, as well as methanol, acetaldehyde, and n-propanol contents, than the wine prepared without sulfiting. The ethyl acetate content of the wine without sulfiting was 375.5 mg/L, which was 5.3 times higher than that (70.5 mg/L) with sulfiting. In the sensory evaluation, the wine without sulfiting obtained higher scores in flavor and overall preference than that with sulfiting.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.25-35
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• 1989

To prepare a new type of fish sauce from skipjack scrap, it was examined the effect of koji on the sauce flavor, conditions of low salt fish sauce processing and the changes of taste com-pounds during its fermentation. To prepare the skipjack scrap sauce, chopped skipjack head paste was mixed with $6.6\%$ skipjack viscera, $26.9\%$ koji, $71\%$ of $25\%$ brine, $13.3\%$ salt and $7.6\%$ glucose, and fermented at $25\pm4^{\circ}C$ for 90 days. The same process was also carried out to prepare the low salt skipjack scrap sauce adding $7.6\%$ sorbitol, $0.3\%$ lactic acid and $9.8\%$ ethyl alcohol instead of $13.3\%$ salt. The major free amino acids in the products were glutamic acid, Iysine, valine, phenylalanine, alanine, leucine and isoleucine at 90 days of fermentation. And the contents of total free amino acids in both products were 3,307mg/00m1, 3,637.1mg/100m1 at 90 days of fermentation. The predominating non-volatile organic acids showed in the products were lactic acid, succinic acid, pyroglutamic acid, which were $90\%$ over contents of the total non-volatile organic acids. Total non-volatile organic acid contents in both products were 1,002.1mg/100ml, 1,312.9mg/100m1 at 90 days of fermentation. During fermentation of sauce, ADP, AMP and IMP were decreased, while inosine and hypoxanthine were increased. The major taste compounds of the products were rove진ed free amino acids and non-volatile organic acids. The nucleotides and their related compounds, total creatinine, betaine, TAMO and sugar were seemed to be having an auxiliary role in taste of those products. Fishy odor in skipjack scrap sauce can be improved by adding koji. And the low salt skipjack scrap sauce ($9.12\%$ of salt contents) can be prepared by the replacement of a part of salt with sorbitol, lactic acid and ethyl alcohol. From the results of sensory evaluation and chemical experiments, the skipjack scrap sauce products supposed to be at least equal to the sold soy sauce on the market in quality.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.917-924
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• 1995

Four types of soybean paste(Doenjang), prepared with traditional Korean meju, natto meju, koji and mixture of koji and natto meju, were analyzed for compositions of free sugars and fatty acids. Crude protein content of the soybean pastes were ranged from 10.3~14.6% and in the order of traditional Korean soybena paste>natto soybena paste>koji & natto soybean paste>koji soybean paste during fermentation of Doenjang. Ethyl alcohol contnet was relatively higher in koji and natto soybean paste after fermentation for 75 days, and its content was the highest in koji soybean paste as 2.8% after fermenting for 90 days. Contents of total sugars and reducing sugars decreased during fermentation of doenjang in the order of koji soybena paste>koji and natto soybean paste>traditional soybean paste>natto soybean paste. Among the free sugars glucose, galactose, mannose and arabinose were identified in soybean paste, and glucose and galactose were more bundant. Contents of glucose and total free sugars were the highest in the traditional Korean soybean paste and galactose content was highest in koji soybean paste. In fatty acid compositions of soybean pastes, palmitic, stearic, oleic, linoleic, linolenic and arachidonic acids were analyzed, and the most abundant fatty acid was found to be oleic acid as 38.5~46.9% in all samples tested. But no significant differences in ratio of fatty acid compositions was observed from tested samples during the fermentation period.

• Journal of Life Science
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• v.30 no.7
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• pp.598-605
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• 2020

Padina gymnospora is a brown algae of the class Phaeophyceae. It has been established that P. gymnospora ameliorates amyloid-β-induced neuropathology and has an anticoagulation effect, but this study was designed to estimate its skin-whitening effect and identify its active component. The ingredients of P. gymnospora were extracted with ethanol and its activity was compared with arbutin. First, the P. gymnospora extract was observed to inhibit tyrosinase activity in a dose-dependent manner, tyrosinase being the rate-limiting enzyme of melanin synthesis. Notably, where 200 μM of arbutin inhibited tyrosinase activity by 58.1%, P. gymnospora extract (0.5%) achieved 76.7%. The P. gymnospora extract also significantly reduced α-melanocyte-stimulating hormone-induced TRP-1 and TRP-2 mRNA expression. In addition, it significantly inhibited melanin synthesis in B16F10 melanoma cells. We identified the 0.66% fucosterol content that inhibited melanin synthesis as comparable to that of arbutin. Additionally, we tested the potential cytotoxicity of P. gymnospora by MTT and LDH release assay and found that the extract significantly reduced LDH release in CCD-986sk cells. These results indicate that P. gymnospora extract could be a potential active ingredient of cosmetics with a skin-whitening effect.