• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.779-785
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• 1996

Sansung takju, the Korean traditional liquor at a local area of Sansung in Pusan, has been widely drunken due to its tradition in this area. The studies on microorganisms of kokja, fermentation process and shelf-life of takju were carried out. The most abundant microorganism identified from a commercial Sansung kokja was Aspergillus, Mucor, Rhizopus and Penicillium were also identified. In case of a home-made Sansung kokja, Mucor was the most abundant one. Aspergillus, Rhizopus and Absidia were also identified in it. Saccharomyces, Micrococcus and Bacillus were identified in both kokja's but acid production bacteria were not found. Ethanol fermentation was carried out at $25^{\circ}C$ and $30^{\circ}C$ using each kokja. The rate of ethanol production was faster at $30^{\circ}C$ than at $25^{\circ}C$, while higher viable yeast count and final ethanol content were obtained at $25^{\circ}C$ than at $30^{\circ}C$. The ethanol contents of the mashes using a commercial Sansung kokja and a home-made Sansung kokja after 14 days at $25^{\circ}C$ were 11.0% and 12.4%, respectively. The shelf-life of takju was affected more by ethanol content in the product than by storage temperature. The product stored at $-15^{\circ}C$ did not change significantly in acidity but tasted watery due to thawing. In case of Sansung takju containing 6%ethanol, level of acidity increased and pellicle was formed on the surface of the product during storage at $30^{\circ}C$. In case of Sansung takju containing 9% or 12% ethanol, no significant changes in acidity and appearance were observed for 14 days at $30^{\circ}C$.

• Economic and Environmental Geology
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• v.39 no.5 s.180
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• pp.583-595
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• 2006

Quartz veins from the Hwawon area are an epithermal quartz vein that is filling the fault zone within Precambrian metasedimentary rocks and Jurassic granite. Mineralization can be divided into hypogene and supergene stages. Hypogene stage is associated with hydrothermal alteration minerals(propylitic and argillic zones) such as epidote, chlorite, illite, sericite and sulfides such as pyrite, sphalerite, chalcopyrite, galena, bornite, cubanite, argentian tetrahedrite, Pb-Ag-S system and Pb-Te-S system. Supergene stage is composed of Fe-Mn oxide, Zn-Fe oxide and Pb oxide. Fluid inclusion data indicate that homogenization temperatures and salinity of hypogene stage range from $291.2^{\circ}C$ to $397.3^{\circ}C$ and from 0.0 to 9.3 wt.% eq. NaCl, respectively. It suggests that ore forming fluids were cooled and diluted with the mixing of meteoric water. Oxygen($-0.7{\sim}3.5%_{\circ}$(white quartz: $-0.7{\sim}3.5%_{\circ}$, transparent quartz: $2.4%_{\circ}$)) and hydrogen($-70{\sim}55%_{\circ}$(white quartz: $-70{\sim}55%_{\circ}$, transparent quartz: $-62%_{\circ}$)) isotopic composition indicates that hydrothermal fluids were derived from magmatic and evolved by mixing with meteoric water during mineralization.

• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.110-115
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• 2000

This study was conducted to monitor the irrigation water qualities along Dong-Jin river watershed. The water quality was surveyed at 6 sites from April to september during $1994{\sim}1998$. And the results were as follows : In July and August, water quality was better than that of any other months due to dilution with rainwater. Whereas, it became worse in April but it involved lower contents than limitted contents affected to the crop damage. Content of inorganic components was higher at Jeong-up and Won-pyeong stream. The reason for it that Jeong-up stream was deteriorated with sewage water from Jeong-up city, and Won-pyeong stream has narrow width. Water quality in upstream of Dong-Jin river, was evaluated best conditions in all sampling sites. For investigated period, water quality got worse from 1994 to 1995 but it was getting better to 1998 after 1995, especially at Jeong-up stream. The total equivalent of cation and anion was the highest at April through all months and at Jeong-up stream in sampling sites. Equivalent ratio of cation to $anions({\Sigma}C/{\Sigma}A)$ was higher at May than any other months and lower at Won-pyeong streams than any other sites. The value of most inorganic components was highly correlated with those of other components. But the value of $NO_3\;^--N$ was not correlated with that of most components, and $PO_4\;^{3-}-P$ was not correlated with COD, $NH_4\;^+-N$, $NO_3\;^--N$, $SO_4\;^{2-}$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.12
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• pp.1193-1199
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• 2012

A cup burner experiment was performed to investigate the effect of the oxidizer velocity and concentration on flame instability near extinction. Heptane was used as a fuel and air diluted by nitrogen and carbon dioxide was used in the oxidizer stream. Two types of flame instabilities at the flame base and at axial downstream were observed near extinction. The instability at the flame base could be characterized by cell, swing, and rotation modes, and the cell mode changed to the rotation mode through the swing mode as the oxidizer velocity increased. To assess the parameters for the flame instability, the initial mixture strengths, Lewis number, and adiabatic flame temperature were investigated under each condition. The Lewis number might be the most important among them, but it is impossible to generalize because of the insufficient number of cases. Furthermore, the axial periodic flickering motion disappeared at low and high oxidizer velocities near extinction. This resulted from the fact that low oxidizer velocity induced evaporated fuel velocity below the critical velocity and high velocity made the reacting fuel velocity comparable.

• Korean Journal of Microbiology
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• v.48 no.1
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• pp.42-47
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• 2012

Hydrothermal vents (HTV) provide special environments for evolution of lives independent on solar energy. HTV samples were gained from Tofua arc trench in Tonga, South Pacific. We investigated archaeal diversity enriched using combinations of various electron donors (yeast extract and $H_2$) and electron acceptors [Iron (III), elemental sulfur ($S^0$) and nitrate. PCR amplification was performed to detect archaeal 16S rRNA genes after the cultures were incubated $65^{\circ}C$ and $80^{\circ}C$ for 2 weeks. The cultures showing archaeal growth were transferred using the dilution-to-extinction method. 16S rRNA gene PCR-Denaturing Gradient Gel Electrophoresis was used to identify the enriched archaea in the highest dilutions where archaeal growth was observed. Most of cultured archaea belonged to genus of Thermococcus (T. alcaliphilius, T. litoralis, T. celer, T. barossii, T. thoreducens, T. coalescens) with 98-99% 16S rRNA gene similarities. Interestingly, archaeal growth was observed in the cultures with Iron (III) and nitrate as an electron acceptor. It was supposed that archaea might use the elemental sulfur generated from oxidation of the reducing agent, sulfide. To cultivate diverse archaea excluding Thermococcus, it would be required to use other reducing agents instead of sulfide.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.252-259
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• 2009

This study investigated the effects of ion water and premixed mineral supplementation on the growth performance, carcass, and meat quality parameters in finishing pigs ($LY{\times}D$). Each 20 pigs were randomly allotted to three treatments; CON (basal diet), T1(CON diet added with active water), T2 (T1 diet added with 1.0% premixed mineral). Used ion water and premixed mineral were consisted mainly of Zn and Si, respectively. Daily weight gain feed efficacy were the highest in T2, while fat content was the highest in control (p<0.05) than the others. However, the slaughter qualities including dressing percent, backfat thickness, marbling score, meat color, meat texture, drip loss, meat separation and meat qualities including pH, cooking loss, water holding capacity (WHC), shear force, meat color, backfat color, meat texture were not significantly different (p>0.05) among the treatment groups. Panel test scores of tenderness were the highest in T2 compared to the others.

• Korean Journal of Medicinal Crop Science
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• v.6 no.4
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• pp.277-285
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• 1998

Antifungal activity on major seedborne diasease of crops was screened by the treatment of the extracts from 50 medicinal plants in vitro and in vivo. The extracts of garlic and taxus, Rheum undulatum, Achiranthes japonica, Glycyrrhiza uralensis, Oenothera lamar kiana treated with the blotting filter paper and water agar methods inhibited the growth of Pyricularia oryzae, Alternaria sesamicola, Colletotrichum gloeosporioides, and Alternaria brassicicola among the tested plants. Antifungal activities on infected seeds by soaking methods were shown even at the dilution of the extracts by 10 times. The activity was the highest in soaking seeds at $25^{\circ}C$ for 24 hours. The effect of plant extract on seed germination was not significant as compared with untreated seed. However, early growth of seedling was increased by the treatment of extracts. The extract of taxus slightly inhibited the seed germination of radish and chinese cabbage but those of Achirunthes japonica, Glycyrrhiza uralensis and Oenthfera lamarkiana showed severe damage on the seed germination and early growth of seedling.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.151-156
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• 2009

Samhaeju is a traditional Korean noble rice wine, in which its processing is performed at low temperatures for an extended fermentation time and with three brewing steps. In this study, Samhaeju was prepared by different brewing methods that were modified from the method in the literature. Chemical composition of samples were determined to evaluate the quality of the Samhaeju. The Samhaeju was analyzed for pH, total acids, amino nitrogen, Hunter color values, free sugars, organic acids, and volatile components. Before the addition of the second and third mashing, pH values had decreased slightly and total acids had rapidly increased. Free sugar and amino nitrogen contents were high in final product. After addition of the third mashing as the advanced step, a dilution effect was shown. Glucose (A: 0.77-7.0%, B: 0.77-3.81%) was a major free sugar, and lactic acid (A: 0-2,840mg%, B: 0-3,375mg%) was a major organic acid during the entire period of fermentation. Based on principal component analysis of electronic nose data for the components, the stages of Samhaeju fermentation were primarily separated along the first principal component (PC, proportion : 98.67%). The first PC component (PC1) was moved from negative value(-6.16) to positive value(9.00) with increasing fermentation time. The change patterns for pH and total acid during the fermentation period were similar to those of PC1 from the data obtained by electronic nose based on mass spectrometry.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.153-163
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• 2013

The Ogcheon Au-Ag deposit consists of two quartz veins that fill the NE or NW-trending fissures in the metasedimentary rocks of unknown age. The quartz veins occur mainly in the massive type with partially breccia and cavity. They can be found along the strike for about minimum 50 m and varied in thickness from 0.1 to 0.3 m. The mineralogy of quartz veins from the Ogcheon deposit is mainly composed of hydrothermal alteration minerals such as pyrite, quartz, sericite, chlorite, clay minerals and sulfides including pyrite, pyrrhotite, arsenopyrite, sphalerite, chalcopyrite and galena. Fluid inclusion data from quartz indicate that homogenization temperatures and salinity of mineralization range from 184 to $362^{\circ}C$ and from 0.0 to 6.6 wt.% eq. NaCl, respectively. These suggest that ore forming fluids were progressively cooled and diluted from mixing with meteoric water. Sulfur(${\delta}^{34}S$: 0.4~8.4‰) isotope composition indicates that ore sulfur was derived from mainly magmatic source although there is a partial derivation from the host rocks. The calculated oxygen(${\delta}^{18}O$: 4.9~12.1‰) and hydrogen(${\delta}D$: -92~-74‰) isotope compositions suggest that magmatic and meteoric ore fluids were equally important for the formation of the Ogcheon deposit and then overlapped to some degree with another type of meteoric water during mineralization.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.57-62
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• 2002

The purpose of this study was to investigate the antibacterial activity of green tea in mayonnaise against pathogenic bacteria (Escherichia coli O157:H7 and Salmonella typhimurium). Mayonnaise was prepared with salad oil, egg yolk, sugar, salt and vinegar, and green tea powder was added to the mayonnaise at 0.1, 0.3 and 0.5% for the experiment. Then, the mayonnaise samples with various levels of green tea were inoculated with about 10$\^$6/ cells/g of E. coli and S. typhimurium per 1 gram of mayonnaise and stored at 5$^{\circ}C$, 15$^{\circ}C$ and 25$^{\circ}C$ for 3∼9 days. Antibacterial activity of green tea was tested by the colony counting method for E. coli on violet red bile agar(VRBA) and S. typhimurium on xylose lysine desoxycholate agar(XLDA). The D-values of E. coli controls were 2.89, 2.73 and 2.13 days while those of S. typhimurium controls were 0.58, 0.53 and 0.52 days at 5$^{\circ}C$, 15$^{\circ}C$ and 25$^{\circ}C$, respectively Inhibitory effect of green tea in mayonnaise on the survival of E. coli and S. typhimurium was increased with increasing concentration of green tea and/or increasing storage temperature. The most effective antibacterial activity of green tea was shown against E. coli in mayonnaise during storage at 25$^{\circ}C$.