• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.139-142
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• 1984

Short-term acute toxicity of synthetic detergent(LAS) to larvae of loach, Misgurnus angillicaudatus was examined by static bioassay. The larvae were exposed to 15 different concentration of synthetic detergent for 16, 48, 72, 96 and 120 hours in order to determine median lethal concentration($LC_{50}$). The $100\%$ mortarlity of larvae was showed within 120, 96, 48 and 16 hours for 6, 18, 30 and 38 ppm, respectively. The median lethal concentration values of the larvae were 12.59 ppm for 48 hours, 4.00 ppm for 96 hours and 1.02 ppm for 120 hours. The permissible toxicant concentration of acute toxicity to larvae was $0.37{\sim}0.43$ ppm, and application factor of the synthetec detergent was $0.093{\sim}0.108$. The median lethal time($LT_{50}$) for different concentration also was determined. The $LT_{50}$ of 0.2 ppm was found within 165.1 hours and 2 ppm was 106.2 hours, while the $LT_{50}$ of 8 ppm was 60.3 hours and that of 38 ppm was 23.5 hours.

• Journal of the Korean earth science society
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• v.27 no.1
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• pp.49-60
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• 2006

The purpose of this study is to investigate geochemical characteristics for stream sediments in the Naju area. We collected 139 stream sediments samples from primary channels. Samples were dried slowly in the laboratory and chemical analysis was carried out using XRF. ICP-AES and NAA. In order to investigate geochemical characteristics, the geological groups categorized into granitic gneiss area, schist area, granite area, arenaceous rock area, tuff area, andesite area, and rhyolite area. Average contents of major elements for geological groups are $SiO_2\;58.37{\sim}66.06wt.%,\;Al_2O_3\;13.98{\sim}18.41wt.%,\;Fe_2O_3\;4.09{\sim}6.10wt.%,\;CaO\;0.54{\sim}1.33wt.%,\;MgO\;0.86{\sim}1.34wt.%,\;K_2O\;2.38{\sim}4.01wt.%,\;Na_2O\;0.90{\sim}1.32wt.%,\;TiO_2\;0.82{\sim}1.03wt.%,\;MnO\;0.09{\sim}0.15wt.%,\;P_2O_5\;0.11{\sim}0.18wt.%$. According to the comparison of average contents of major elements, $Al_2O_3\;and\;K_2O$ are higher in granitic gneiss area, $Fe_2O_3,\;CaO,\;P_2O_5$ are higher in tuff area, MgO and $TiO_2$ are higher in andesite area, $Na_2O_$ is higher in rhyolite area, $SiO_2$, and MnO are higher in arenaceous rock area. Average contents of minor and rare earth elements for geological groups are $Ba\;1278{\sim}1469ppm,\;Be\;1.1{\sim}1.5ppm,\;Cu\;18{\sim}25ppm,\;Nb\;25{\sim}37ppm,\;Ni\;16{\sim}25ppm,\;Pb\;21{\sim}28ppm,\;Sr\;83{\sim}155ppm,\;V\;64{\sim}98ppm,\;Zr\;83{\sim}146ppm,\;Li\;32{\sim}45ppm,\;Co\;7.2{\sim}12.7ppm,\;Cr\;37{\sim}76ppm,\;Cs\;4.8{\sim}9.1ppm,\;Hf\;7.5{\sim}25ppm,\;Rb\;88{\sim}178ppm,\;Sc\;7.7{\sim}12.6ppm,\;Zn\;83{\sim}143ppm,\;Pa\;11.3{\sim}37ppm,\;Ce\;69{\sim}206ppm,\;Eu\;1.1{\sim}1.5ppm,\;Yb\;1.8{\sim}4.4ppm$. According to the comparison of average contents of minor and rare earth elements for geological groups, Pb, Li, Cs, Hf, Rb, Sb, Pa, Ce, Eu, and Yb are higher in granitic gneiss area; Ba, Co, and Cr in schist area; Nb, Ni, and Zr in arenaceous rock area; Sr in tuff area: and Be, Cu, V, Sc, and Zn are such in andesite area.

• Journal of fish pathology
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• v.20 no.3
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• pp.315-325
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• 2007

Histological changes in gill and liver of eel, Anguilla japonica (average weight 96±3.6 g) were examined with formalin bath at 0~500 ppm for 1, 6 and 24 h. Hyperplasia, hypertrophy, cell fusion, desquamation and necrosis of epithelial cells at gill lamella and gill filament were observed from 6 h at 200 ppm, 1 h at 300 ppm, 1 h at 400 ppm and 1 h at 500 ppm. In the exposure of formalin 100 ppm for 24 h, epithelial cells arrangement of gill filament and gill lamella showed thinner and more regular order than the control. trophy and pyknosis of hepatocytes, congestion at sinus or central vein, degeneration of cytoplasm were observed in the liver from 24 h at 100 ppm and 200 ppm, 6 h at 300 ppm, 1 h at 400 ppm and 500 ppm. However, there were not any histological changes at liver of 100 ppm-1, 6 h, 200 ppm-1, 6 h and 300 ppm-1 h compared with the tissue of control.

• Journal of environmental and Sanitary engineering
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• v.11 no.3
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• pp.79-84
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• 1996

In order to determine the content of heavy metal in common salts, 35 bay salt samples, 7 refined salt samples, 7 fine salt samples, 5 bake salt samples and 5 bamboo bake salt samples were collected from old market in major cities. Heating bay salt 35 samples, it made heating bay salt of $500^{\circ}C$, /TEX>(34 samples), heating bay salt of $1000^{\circ}C$(35 samples). These were analysed for contents of lead(Pb), cadmium(Cd), iron(Fe) and zinc(Zn) by atomic absorption spectrophotometer. The results were as follows : Mean content of lead in bay salts was $0.124{\pm}0.035ppm$ refined salt was $0.130{\pm}0.019ppm$, fine salt was $0.073{\pm}0.036ppm$ bake salt was $0.097{\pm}0.023ppm$, bamboo bake salt was $0.117{\pm}0.020ppm$, heating bay salt was $0.063{\pm} 0.021ppm$ in $500^{\circ}C$, heating bay salt was $0.063{\pm}0.039ppm$ in $1000^{\circ}C$. And bay salt refined salt bamboo bake salt were not significant one another. Mean content of cadmium in bay salts was $0.031{\pm}0.008ppm$ refined salt was $0.032{\pm}0.003ppm$, fine salt was $0.037{\pm}0.005ppm$, bake salt was $0.169{\pm}0.117ppm$ bamboo bake salt was $0.079{\pm}0.052ppm$, heating bay salt of $500^{\circ}C$ was $0.030{\pm}0.029ppm$ heating bay salt of $1000^{\circ}C$ was $0.017{\pm}0.013ppm$. And bay salt refined salt, fine salt were not significant one another. Mean content of iron in bay salts was $1.025{\pm}0, 634ppm$, refined salt was $0.359{\pm}0.163ppm$ fine salt was $0.267{\pm}0.068ppm$, bake salt was $2.929{\pm}1.963ppm$, bamboo bake salt was $5.378{\pm}3.676ppm$, heating bay salt of $500^{\circ}C$ was $0.847{\pm}0.315ppm$ heating bay salt of $1000^{\circ}C$ was $0.991{\pm}0.868ppm$. And bay salt refined salt, fine salt, bake salt, bamboo bake salt were significant one another(p<0, 01). Mean content of zinc in bay salts was $0.253{\pm}0.154ppm$, refined salt was $0.263{\pm}0.091ppm$ fine salt was $0.187{\pm}0.015ppm$, bake salt was $0.166{\pm}0.034ppm$, bamboo bake salt was $0.282{\pm}0.064ppm$, heating bay salt of $500^{\circ}C$ was $0.253{\pm}0.085ppm$, heating bay salt of $1000^{\circ} C$ was $0.242{\pm}0.179ppm$. And bay salt refined salt fine salt, bake salt, bamboo bake salt were not significant one another.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.31-38
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• 1982

The water quality at the Nakdong River stream was surveyed for 3 years from 1978 to 1980 at quarterly intervals of January, April, June and October at 12 sites along the main stream from Sangju to Imhaejin and at 2 sites of Geumho and Nam River tributaries. The overall results are summarized as follows: 1) The levels of dissolved oxygen in the Geumho River tributary on the basis of three-year average were 0.7 ppm in January, 1.3 ppm in April, 4.0 ppm in July and 0.8 ppm in October. BOD concentrations in the same period were 91 ppm in January, 37 ppm in April, 6 ppm in July and 24 ppm in October. The water of Geumho River was so highly contaminated that the water seems to be unsuitable for any type of water use. 2) The relatively clean water in the upstream of the main Nakdong River was rapidly polluted by the highly contaminated water of Geumho tributary. That is, dissolved oxygen and BOD at Hwawon site right after junction of the tributary were 10.4, 8.8 ppm in January, 5.8, 6.5 ppm in April, 6.3, 3.2 ppm in July and 7.0, 5.3 ppm in October, respectively. The values of turbidity, ammoniacal nitrogen and electrical conductivity were also observed to be quite high.

• Electrical & Electronic Materials
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• v.7 no.2
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• pp.130-137
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• 1994

Indium, element of group III, was refined by using zone refining for high purity refinement. We have found the impurities of T1, Zn, Fe, Cd, Pb, Ni, Cu, Sn in the refined indium with ICP-AES, so that 3.9 weight ppm of T1 was reduced to less than 1 ppm, 1.0 weight ppm of Zn was reduced to 0.7 ppm, 2.8 weight ppm of Cd was reduced to 2.5 ppm and 14.0 weight ppm of Sn was reduced to 6.7 ppm with 5 melten zone passes only. 3.9 weight ppm of T1 was reduced to less than 1 ppm, 1.0 weight ppm of Zn was reduced to 0.3 ppm, 2.8 weight ppm of Cd was reduced to less than 1.0 ppm and 14.0 weight ppm of Sn was reduced to 0.4 ppm after vacuum baking with 5 melten zone passes. The surface morpholgy of metal Indium thin film in each conditions showed that porosities were reduced in the front of sampled ingot after vacuum baking with 5 zone melten zone passes. The average electrical resistivity of Indium thin film was reduced from 1.4*10$^{-3}$ .ohm.-cm in Indium origin ingot to 7.9*10$^{-6}$ .ohm.-cm after zone refined with 5 melten zone passes.

• Economic and Environmental Geology
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• v.37 no.2
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• pp.173-184
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• 2004

The geochemical exploration was carried out of the soil systems in the survey areas(Mt. Subang area). The chemical values of soil samples for soil in this area are defined such as over values of Ag : 11 ppm(Average ： 1.91 ppm), Au 548 ppb(Average 42.39 ppb), Cu : 89 ppm(Average：51.40 ppm), Pb：190 ppm(Average ： 23.69 ppm), Zn : 157 ppm(Average : 61.78 ppm), respectively. Anomalous areas for each element have been chosen based on the factors such as, geologic settings, geochemical survey, chemical analysis of ore, chemical analysis of soil. statistical processing of the chemical analysis. Therefore, multi-elements anomalies area were recognized in the east-center part of the study area.

• Journal of Sericultural and Entomological Science
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• v.39 no.1
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• pp.12-16
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• 1997

Effects of calcium on mulberry growth and freezing tolerance were examined by water culture. Calcium was supplied by folar spray with the levels of 0, 5, and 40 ppm. Muberry stems developed by 130 cm at Ca2+ 40ppm, 82 cm at Ca2+ 5 ppm and 23 cm at Ca2+ 0 ppm. Muberry roots also developed vigorously at Ca2+ 40 ppm, but did poorly at Ca2+ 5 ppm and changed to brown in color, and died becoming necrosis at Ca2+ 0 ppm. Content of calcium in leaves and barks were increased at Ca2+ 40 ppm compared with at Ca2+ 5 ppm. Total sugar, RNA, proline and phospholipid at Ca2+ 40 ppm were also more increased than those at Ca2+ 5 ppm. Mulberry stems grown at Ca2+ 40 ppm showed a sufficient tolerance at -10 for 24 hours while stems grown at Ca2+ 5 ppm did a weak tolerance at the same conditions.

• The Korean Journal of Food And Nutrition
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• v.21 no.1
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• pp.15-21
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• 2008

In this study, the minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae and Salmonella enteritidis were tested. The MICs of the water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 312.5 ppm, below 156.3 ppm, 625 ppm, 10,000 ppm, above 10,000 ppm, 10,000 ppm, above 10,000 ppm, above 10,000 ppm, 10,000 ppm, and above 10,000 ppm, respectively. The growth inhibition concentrations against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae were 156.3 ppm, below 156.3 ppm, 625 ppm, 5,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, and 5,000 ppm, respectively. However, 10,000 ppm did not inhibit the growth of Salmonella enteritidis. Finally, the colony forming inhibitory activities against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 98.0%, 99.8%, 69.8%, 98.1%, 62.0%, 63.1%, 79.5%, 61.9%, 79.6%, and 0.0%, respectively.

• Korean journal of food and cookery science
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• v.4 no.1
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• pp.53-57
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• 1988

To obtain basic data for the development of domestic tea manufacture, the physico-chemical properties were analyzed. The content of crude fiber in domestic black tea was abundant of 50%, as compared with those in Sri-Lanka's black tea, while the contents of tanin and caffeine were lower than those of Sri-Lanka's Products. The quantities of mineral in Sri-Lanka's products were determined as 300ppm P, 15,000ppm K, 1,400ppm Mg, 4,000ppm Ca, 22ppm Cu, 21ppm Cr and 45ppm Zn. These contents were higher than those of domestic products. Al content was 4,100ppm in domestic products. Pb and Cd were not detected in two kinds of black tea products. In Sri-Lanka's black tea, 8 kinds of organic acids were identified and the major organic acids were shikimic, citric and quinic acid, while 6 kinds of organic acids were identified in domestic products and were quinic and gallic acid, as the major organic acids. The content of sucrose was higher than that of Sri-Lanka's product and theaflavin, thearubigin and theobromine were abundant, as compared with those in domestic products.