• Economic and Environmental Geology
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• v.35 no.1
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• pp.1-12
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• 2002

Manus Basin, located in the equatorial western Pacific, is a back arc basin formed by collision between the IndoAustralian and the Pacific Plates. The basin is host to numerous hydrothermal vent fields and ore deposits. The basement rocks of the Manus Basin consist primarily of dacite and basaltic andesite. Some of the minerals that form the hydrothermal chimneys that were dredged on the Manus basin include pyrite, chalcopyrite, marcasite, sphalerite and galena. The chimneys can be classified into chalcopyrite dominant Cu-rich type and sphalerite dominant Zn-rich type. The concentration of Zn shows good positive correlation with that of Sb, Cd and Ag. The content of Cu, on the other hand, positively correlates with that of Mo, Mn and Co. For samples that were taken from Zn-rich chimney, a strong positive correlation is found between Au and Zn contents. The chimney also shows enrichments of Cd, Mn and Sb. On the other hand, the samples from Cu-rich chimney exhibit strong correlation among Au, Zn and Pb, and are enriched in Mo and Co concentration. Average contents of Au in Cu-rich and Znrich chimneys were 15.9 ppm and 29.0 ppm, respectively. Because of high concentration of Au with Ag and Cu, the ore deposit have high economic potential. Homogenization temperatures and salinities of fluid inclusions in anhydrite and amorphous silica from Zn-rich chimney are estimated to be l74-220$^{\circ}$C and 2.7-3.6 equiv. wt. % NaCI, respectively. These value suggest that ore forming processes were occurred at around 200$^{\circ}$C and that the oxygen fugacity changed from 2: 10$^{-39.5}$bar to -s: 10$^{-40.8}$bar and the sulfur fugacity from -s: 10$^{-14.7}$bar to 10$^{-13.4}$bar during the process. It appears that the temperature at which the ores formed on Cu-rich chimney was higher than that on Zn-rich chimney.

• Journal of Life Science
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• v.16 no.6
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• pp.911-918
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• 2006

The purpose of this study was to observe the effects of the feeding physiological activity substance in Saururus chinensis Baill extract on the improvement of the blood glucose, electrolyte (Na, K, CI) concentration and lipid metabolism in the serum of streptozotocin (STZ, 55 mg/kg B.W., I.P. injection)-induced hyperglycemic rats fed the experimental diets for 5 weeks. Concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, triglyceride (TG) and phospholipid (PL) in serum were significantly higher in the hyperglycemic group (group NSW), STZ (I.P.)+Saururus chinensis Baill leaf 3.5 g% extract group (group NSSL) and STZ (I.P.)+Saururus chinensis Baill root 3.5 g% extract group (group NSSR) than those in the control group (group Normal, basal diet+water). But the concentrations of blood glucose, total cholesterol, atherosclerotic index, LDL, LDL-cholesterol, free cholesterol, cholesteryl ester ratio, TG and PL in serum were remarkably lower in the groups NSSL and NSSR than those in the NSW, whereas the ratio of HDL-cholesterol concentration to total cholesterol and HDL-cholesterol concentration in the groups NSSL and NSSR were significantly higher than in the group NSW. Electrolyte and creatinine concentrations in serum were significantly lower in the groups NSSL and NSSR than those in the group NSW. The activities of aminotransferase (AST, ALT), creatine phosphokinase (CPK), lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) in serum were remarkably lower in the groups NSSL and NSSR than in the hyperglycemic group NSW. However, no significance was found in the comperative effect of the groups NSSL and NSSR. From the above results, it was suggested that Saururus chinensis Baill was effective in the improvement of the blood glucose, electrolyte, glucide and lipid metabolism in serum of STZ-induced hyperglycemic rats.

• Analytical Science and Technology
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• v.27 no.1
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• pp.1-10
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• 2014

The $PM_{10}$ and $PM_{2.5}$ samples were collected at Gosan Site of Jeju Island, and analyzed, in order to investigate the size distribution and pollution characteristics of their components. $NH{_4}{^+}$, nss-$SO{_4}^{2-}$, $K^+$, and $CH_3COO^-$ were mostly existed in fine particles. Meanwhile, $NO{_3}{^-}$ was distributed in both fine and coarse particles, and $Na^+$, $Cl^-$, $Mg^{2+}$, nss-$Ca^{2+}$ were rich in coarse particle mode. The concentrations of nss-$Ca^{2+}$ and $NO{_3}{^-}$ were increased 36.7 and 3.2 times in coarse particles, and 15.0 and 3.1 times in fine particles during the Asian Dust periods. Especially, the concentrations of crustal elemental species such as Al, Fe, Ca, K, Mg, Ti, Mn, Sr, Ba were highly increased for those periods. In the haze events, the concentrations of secondary air pollutants were increased 1.3~2.6 and 1.5~4.2 times in coarse and fine particles, respectively. Moreover, the remarkable increase of $NO{_3}{^-}$ concentration was also observed in fine particle mode. The factor analysis showed that the composition of coarse particles was influenced mainly by marine sources, followed by soil and anthropogenic sources. On the other hand, the fine particles were influenced by anthropogenic sources, followed by marine and soil sources.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.3
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• pp.131-140
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• 2000

Compostable household wastes(mainly food residues) were composted in a small bin for 30 days, in which compostable household wastes were fed every day and mixed thoroughly under aerobic conditions. Three small bins were employed. In the first bin only recycled compost was composted, in the second, compostable household wastes with recycled compost, and in the third compostable household wastes with recycled compost and vermiculture. The correct decomposition rate of each composting material was calculated during composting. Total reduced rate of the weight after 30 days was 57.32% when composting the compostable household wastes with recycled compost, and 64.71% when composting them with recycled compost and vermiculite. In the case of composting the compostable household wastes with the recycled compost, the total weight reduction rate for a day was 6.81% and the total decomposition rate 6.81%. Their difference was not great. But in the case calculated with only compostable household wastes the total weight reduction rate was 56.34% and the decomposition 6.79%. When compostable household wastes were composted with the recycled compost and vermiculite, the total weight reduction rate was 64.99% and the decomposition rate 1.48%, but the total weight reduction 4.36% and the decomposition rate 35.46% when calculated with only compostable household wastes. MgO, $K_2O$ and Cr concentrations in the composting mixture during the early composting time were higher when composted with vermiculite than without it, but organic matter, CaO, NaCl, and $P_2O_5$ concentrations were contrarily diluted because of their lower concentration of vermiculite when compostable household wastes were composted with vermiculite.

• Journal of the Korean earth science society
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• v.25 no.6
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• pp.428-442
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• 2004

Dustfall samples were collected by the modified American dust jar (bulk type) at 5 sampling sites in the Nakdong river area from lune 2002 to May 2003. Nineteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Si, V, Zn, $Cl^-$, $NO_3^-$, $SO_4^{2-}$, and $NH_4^+$) were analyzed via the combination of ICP/AES, AAS, IC and UV. The purposes of this study were to qualitatively evaluate the chemical composition of dustfalls by examining their regional and seasonal distribution patterns. Computation of the enrichment factor showed that well-defined anthropogenic sources, particularly in Pb were found in the order Gamjeondong (industrial area), Wondong, Silla University, Samrangiin and Mulgum. The seasonal mean of soil contribution showed its highest value (16.3%) during the winter with an annual mean of 11.2%. The concentration ratio of [$SO_4^{2-}/NO_3^-$] was found to be highest (5.12) during the winter, while the lowest ratio value (3.30) was seen during the all. fall, Also regional equivalent ratios of [$SO_4^{2-}/NO_3^-$] were found in the order: Silla University (6.78), Gamjeondong (4.98), Mulgum (3.95), Wondong (3.85), and Samrangjin (2.87). Seasonal distribution of water soluble components for total dustfall were found in the order: spring (71.6%), summer (61.2%), fall (49.2%) and winter (48.6%) with a mean ratio of 57.6%. Regional contribution of sea salts of water soluble ions were found in the order: Silla university (34.5%), Gamjeondong (28.3%), Wondong (17.3%), Samrangiin (17.2%) and Mulgum (13.8%), the total mean contribution rate was 22.1%. As for the chemical composition of dustftll on the lower Nakdong river, there is a decreased influence of sea salt and artificial anthropogenic sources and increased influence of soil particle inland. Also, the total amount of deposition on the lower Nakdong river has decreased, with the river's surface serving as a confounding factor in resuspending dusts.

• Economic and Environmental Geology
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• v.22 no.4
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• pp.303-314
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• 1989

The electrum-silver-sulfide mineralization of the Geojae island area was deposited in three stages (I, II, and carbonate) of quartz and calcite veins that crosscut Late Cretaceous volcanic rocks and granodiorite(83 m.y.). Stages I and II were terminated by the onset of fractunng and breCCIation events. Fluid inclusion data suggest that the gold-sulfide-bearing stages I and II each evolved from an initial high temperature( near $370^{\circ}C$) to a later low temperature(near $200^{\circ}C$). Each of those stages represented a separate mineralizing system which cooled prior to the onset of the next stage. The relationship between homogenization temperature and salinity in stages I and II suggests a complex history of boiling, cooling and dilution. Evidence of boiling indicates a pressure of < 100 bars, corresponding to a depth of 500 to 1,250m assummg hthostatlc and hydrostatic pressure regimes, respectively. Fluid inclusion and mineralogical evidence suggest that the electrum-silver mineralization was deposited at a temperature of $220-260^{\circ}C$ from ore fluids with salinities between 1.9 and 8.1 equivalent wt.% NaCl. Total sulfur concentration is estimated to be $10^{-3}$ to $10^{-4}$ molal. The estimated $fs_2$ and $fo_2$ range from $10^{-11.8}$ to $10^{-14}$ atm and $10^{-35}$ to $10^{-36}$ atm, respectively. The chemical conditions indicate that the dominant sulfur species in the ore forming fluids was a reduced form($H_2S$). Rapid cooling and dilution of ore-forming fluids by mixing with less-evolved meteoric waters led to gold-silver deposition through the breakdown of the bisulfide complex($Au(HS)_2$) as the activity of $H_2S$ decreased.

• Korean Journal of Environmental Agriculture
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• v.14 no.1
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• pp.15-22
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• 1995

This study was carried out to investigate the deposition aspect of acid precipitation in rural area of Chonbuk province by analysis of the chemical components in the precipitation at National Honam Agricultural Experiment Station, RDA in the suburbs of Iri from Jan. to Dec. in 1992. The results are summarized as follows: 1. The frequency of acid precipitation was 82.5% in 1992 and the month of the lowest frequency of 17% was June. 2. The pH range of the most precipitation amount was pH $4.5{\sim}5.0$ of 54.0% and the amount and ratio of the precipitation below pH 4.0 were 9.6 mm and 1.1%, respectively. 3. The seasonal acidity of precipitation was Summer(4.78)>Fall(4.59)>Spring(4.52)>Winter(4.16). 4. The components showed significant correlation with pH value were $SO_4^{2-}$ and $NO_3$ and the equivalence ratio between two components was 2.85 : 1. 5. The order of the major ion concentration in the precipitation was $SO_4^{2-}$>$NH_4^+$>$Cl^-$>$Ca^{2+}$>$NO_3^-$>$Na^+$>$H^+$>$K^+$>$Mg^{2+}$ and the equivalence ratio of total anion to cation was 1.20. 6. Deposition amount of nitrogen ($NO_3-N$ + $NH_4-N$) and potassium ($K_2O$) were 1.19 and 0.53 kg/l0a/year, respectively.

• Korean Journal of Microbiology
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• v.47 no.2
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• pp.117-123
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• 2011

The purpose of this study was to evaluate and compare different elution and concentration methods for optimization of human rotavirus (HRV) detection method using real-time RT-PCR and cell culture techniques. The leafy vegetable samples (lettuce, Chinese cabbage) were artificially inoculated with HRV. Viruses were extracted from the vegetables by two different elution buffers, buffer A (100 mM Tris-HCl, 50 mM glycine, 3% beef extract, pH 9.5) and buffer B (250 mM Threonine, 300 mM NaCl, pH 9.5), and the extracted viruses were concentrated by filtration and PEG precipitation sequentially. To determine infectivity of the viruses, the viruses recovered from the samples were infected to the MA-104 cells, and integrated cell culture real-time RT-PCR was performed at 1, 48, 72, 96, 120, 144, 168 h post-infection (p.i.). The elution buffer A was more efficient in extracting the virus from the produce samples tested than the buffer B, 29.54% and 18.32% of recoveries, respectively. The sensitivity of real-time RT-PCR method was markedly improved when the virus was concentrated by the filtration method. When the viruses were eluted and concentrated by buffer A and filtration, respectively, the average recovery rate was approximately 51.89%. When the viruses recovered from samples were infected to MA-104 cell, infectious HRV was detected within 48 h p.i. by ICC/real-time RT-PCR, whereas cytopathic effects were not observed until 72 h p.i. The optimized detection method evaluated in this study could be useful for rapid and reliable detection of HRV in fresh produce products and applied for detection of other food-borne viruses.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.58-63
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• 2013

A taxonomic study was carried out to assess the phylogenetic characteristics of isolate JJM57 from marine red algae Laurencia sp. collected from intertidal zone in Jeju Island, South Korea. Comparative analysis of 16S rRNA gene sequence shows that this isolate belongs to the genus Oceanisphaera. It shows 98.02% and 97.7% sequence similarity with Oceanisphera litoralis DSM $15406^T$ and Oceanisphera donghaensis KCTC $12522^T$, respectively. Strain JJM57 is a Gram-negative, aerobic, moderately halophilic bacterium able to grow in different NaCl concentration ranges from 0.5 to 8.0% and at varying temperatures from 4 to $37^{\circ}C$. Sharing some of the physiological and biochemical properties with O. litoralis and O. donghaensis, JJM57 strain differs in the utilization of ethanol, proline, and alanine. The G+C contents of the strain JJM57 is 61.94 mol% and it is rich in $C_{16:1}$ ${\omega}7c$ and/or iso-$C_{15:0}$ 2-OH, $C_{16:0}$, and $C_{18:1}$ ${\omega}7c$ fatty acids. The DNA-DNA relatedness data separates the strain JJM57 from other species such as O. litoralis and O. donghaensis. On the basis of these polyphasic evidences, present study proposed that strain JJM57 (=KCTC 22371 =AM983543 =CCUG 60764) represents a novel bacterial species of Oceanisphaera.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.113-125
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• 2007

To know the differences in ionic compositions in rain and snow as well as snow influence on the chemical characteristics of winter precipitation, precipitation samples were collected by the wet-only automatic precipitation sample, in winter(November-February) in the Iksan located in the northwest of Chonbuk from 1995 to 2000. The samples were analyzed for concentrations of water-soluble ion species, in addition to pH and electrical conductivity. The mean pH of winter precipitation was 4.72. According to the type of winter precipitation, the mean pH of rain was 4.67 and lower than 5.05 in snow. The frequencies of pH below 5.0 in rain were about 73%, while those in snow were about 30%. Snow contained 3 times higher concentrations of sea salt ion components originated from seawater than did rain in winter, mainly $Cl^-,\;Na^+$, and $Mg^{2+}$. Neglecting sea salt ion components, $nss-SO_4^{2-}$ and $NO_3^-$ were important anions and $NH_4^+$ and $nss-Ca^{2+}$ were important cations in both of rain and snow. Concentrations of $nss-SO_4^{2-}$ was 1.3 times higher in rain than in snow, while those of $nss-Ca^{2+}$ and $NO_3^-$ were 1.5 and 1.3 times higher in snow, respectively. The mean equivalent concentration ratio of $nss-SO_4^{2-}/NO_3^-$ in winter precipitation were 2.4, which implied that the relative contribution of sulfuric and nitric acids to the precipitation acidity was 71% and 29%, respectively. The ratio in rain was 2.7 and higher than 1.5 in snow. These results suggest that the difference of $NO_3^-$ in rain and snow could be due to the more effective scavenging of $HNO_3$ vapor than particulate sulfate or nitrate by snow. The lower ratio in snow than rain is consistent with the measurement results of foreign other investigators and with scavenging theory of atmospheric aerosols. Although substantial $nss-SO_4^{2-}$ and $NO_3^-$ were observed in both of rain and snow, the corresponding presence of $NH_4^+,\;nss-Ca^{2+},\;nss-K^+$ suggested the significant neutralization of rain and snow. Differences in chemical composition of non-sea salt ions and neutralizing rapacity of $NH_4^+,\;nss-Ca^{2+}$, and $nss-K^+$ between rain and snow could explain the acidity difference of rain and snow. Snow affected that winter precipitation could be less acidic due to its higher neutralizing rapacity.