• Journal of Environmental Science International
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• v.27 no.11
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• pp.1155-1167
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• 2018

We developed a small sensor observation system (SSOS) at a relatively low cost to observe the atmospheric boundary layer. The accuracy of the SSOS sensor was compared with that of the automatic weather system (AWS) and meteorological tower at the Korea Meteorological Administration (KMA). Comparisons between SSOS sensors and KMA sensors were carried out by dividing into ground and lower atmosphere. As a result of comparing the raw data of the SSOS sensor with the raw data of AWS and the observation tower by applying the root-mean-square-error to the error, the corresponding values were within the error tolerance range (KMA meteorological reference point: humidity ${\pm}5%$, atmospheric pressure ${\pm}0.5hPa$, temperature ${\pm}0.5^{\circ}C$. In the case of humidity, even if the altitude changed, it tends to be underestimated. In the case of temperature, when the altitude rose to 40 m above the ground, the value changed from underestimation to overestimation. However, it can be confirmed that the errors are within the KMA's permissible range after correction.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.761-772
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• 1998

This study was performed to determine the optimum coagulant dosing amount for effective treatment of raw water. The removal rate of turbidity and the variations of water qualities according to various dosage of coagulants such as Alum, PAC and PACS were investigated. The optimum coagulant dosing amount to make the lowest turbidity of water were 35mg/ι t of Alum, 30mg/ι of PAC and 10mg/ι of PACS in case of 5 NTU of raw water turbidity, and 30mg/ι of Alum, 25mg/ι of PAC and 10mg/ι of PACS in case of 10 NTU of that, respectively. The removal rates of turbidity at 4 min. and 8 min. of settling time were 10 and 72% of Alum, 44 and 62% of PAC and 25 and 55% of PACS in case of 5 NTU, and 52 and 70% of Alum, 90 and 95% of PAC and 10 and 28% of PACS in case of 10 NTU, respectively. Judging from the settling capability of floc., the reaction time of floe. formation and removal efficiency of turbidity, PAC was evaluated as more effective coagulant than Alum and PACS. Also PAC was regarded as the most effective coagulant when the water supply was changed sharply and the fluctuation of the surface loading occured with wide and sharp in settling basin. pH and alkalinity of the water were decreased with increasing coagulants dosage. But pH and alkalinity were not decreased below 5.8 which is the standard for drinking water quality, and 10mg/ι which is the limit concentration of floc. breakage, respectively. Residual Al of the treated water was decreased with increasing coagulants dosage in case of 5 and 10NTU of raw water turbidity. $KMnO_4$ consumption of the water was decreased with increasing coagulants dosage. The reduction rate of $KMnO_4$ consumption at the optimum coagulants dosage were 39% of Alum. 18% of PAC and 11% of PACS in case of 5 NTU of raw water turbidity, and 42% of Alum, 27% of PAC and 36% of PACS in case of 10 NTU of that, respectively. Any relationship was not found between the removal rate of turbidity and KMnO$_4$ consumption. TOC of the water was a bit decreased with increasing coagulants dosage up to 30mg/ι but not changed above 30mg/ι of coagulants dosage. The degree of TOC reduction was increased in the order of Alum, PAC and PACS treatment. Zeta potential of the colloidal floe. at the optimum coagulants dosage was in the range of -20~-15mV in case of 5 NTU of raw water turbidity and 0~0.5mV in case of 10 NTU of that. respectively. Although the kinds and dosages of coagulants were different, zeta potential range were fixed under the conditions of the best coagulation efficiency.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.139-146
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• 1978

The annual variations of some heavy metal concentrations, Al, Mn, Fe, Cu, Pb, Zn, Cd, Hg were determined on tile day of spring tides in every month from May 1977 to April 1978 at eight stations in the Nagdong River downstream. Samples were taken at intervals of one or two hours from 7 a.m. to 7 p.m. at each station. Annual ranges and means of concentrations of the heavy metals are as follows : aluminium 40.7-3700 ppb, 286 ppb; manganese 10.3-261.5 ppb, 80.8 ppb; iron ND-1237 ppb, 147.7 ppb; copper ND-30.9 ppb, 2.49 ppb; lead ND-29.9 ppb, 1.10 ppb; zinc ND-156.8 ppb, 5.61 ppb; cadmium ND-1.22 ppb, 0.09 ppb; mercury ND-0.37 ppb, 0.02 ppb respectively. In general, the contents of heavy metals except managanese and mercury were higher at the stations above station one, Kupo, though the ranges of the contents showed remarkable difference according to the sampling stations. Annual means of the concentrations of iron and manganese were exceeded already the desirable standards for industrial water and closed to the criteria of raw water for public supply. The values that over the criteria of raw water were sometimes found. Mercury concentration showed comparative high level such as ND-0.37 ppb in annual range but it was not over the environment criterion, 0.5 ppb. Aluminium, iron and mercury showed generally high values in summer period and other metals in winter period, through the patterns of seasonal variations were difference depending on the sampling stations and the kind of metals.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1161-1168
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• 2009

Ethanol production by the simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% raw starch. For the SSF, the RWC slurry was mixed with the raw-starch-digesting enzyme of Rhizopus sp. and yeast, where the yeast strain was selected from 300 strains and identified as Saccharomyces cerevisiae KV25. The highest efficiency (94%) of ethanol production was achieved when the uncooked RWC slurry contained 23.03% starch. The optimal SSF conditions were determined as 1.125 units of the raw-starch-digesting enzyme per gram of RWC, a fermentation temperature of $30^{\circ}C$, slurry pH of 4.5, 36-h-old seeding culture, initial yeast cell number of $2{\times}10^7$ per ml of slurry, 17 mM of urea as the nitrogen additive, 0.25 mM of $Cu^{2+}$ as the metal ion additive, and a fermentation time of 90 h. Under these optimal conditions, the ethanol production resulting from the SSF of the uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

• Toxicological Research
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• v.26 no.4
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• pp.267-273
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• 2010

As the use of carbon fullerene increases in the chemical industry, the concern over its biological and toxicological effects is also increasing. In this study, the suspension of carbon fullerene (C60) in phosphate buffered saline was prepared and toxicity was investigated using cultured RAW 264.7 and in intraperitoneally injected mice, respectively. The average size of carbon fullerene in the suspension was $53.7{\pm}26.5nm$ when determined by particle size analyzer. Cell viability was significantly decreased by the exposure of carbon fullerene ($0.25\sim2.00\;{\mu}g/ml$) for 96 hrs in the cultured RAW 264.7 cells. Intracellular reduced glutathione (GSH) level was also decreased compared to the level of the non-treated control group during the exposure period, while the level of nitric oxide was increased. When mice were intraperitoneally injected with carbon fullerene, serum cytokine levels of IL-1 and IL-6 were increased with the increased expression of inflammatory genes in peritoneal macrophage and T cell distribution in blood lymphocytes. The results suggested inflammatory responses were induced by carbon fullerene.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.2
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• pp.498-503
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• 2007

Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 are important inflammatory mediators that have been implicated in pathogenesis of inflammation and certain types of human cancers. The present study was designed in order to determine whether Wild ginseng (Panax ginseng C. A. Mayer) could modulate $I{\kappa}B$-kinase (IKK), iNOS and COX-2 gene expression and its immune responses in RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS, 1 ${\mu}/m{\ell}$). Wild ginseng extract dose-dependantly (*0.5 - 2 ${\mu}/m{\ell}$) decreased the LPS-induced IKK, iNOS and COX-2 mRNA expression and its immune responses. Moreover, it inhibited unclear factor (NF)-${\kappa}B$ immune response by LPS. These data be likely to indicate that Wild ginseng may acts as inflammatory regulator and may be possible to develope a useful agent for inflammatory diseases.

• Korean Journal of Veterinary Service
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• v.30 no.3
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• pp.421-428
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• 2007

This study was conducted two kinds of aims: 1) to modify the analytical methods (conditions) by high performance liquid chromatography - fluorescence detector for the detection of residual ivermectin in raw milk, 2) to provide basic information for the evaluation of standard of the residual ivermectin in raw milk. It could be considerable that negative ion spectra can be better method in the LC/MS analysis for the detection of residues, Characteristic daughter ions were observed in negative ion spectra, however, linear line was not formed in positive ion one. Three Holstein cows ($500{\pm}10kg$) were applied to commercial ointment of ivermectin just one time at the first day of test, and residues in raw milk were examined for 20day after administration. The limit of detection (LOD) was 0.65ng (n=5) by HPLC/FLD, and recovery rates were $87.85%{\sim}99.47%$. The peak was observed at the 4th day, and residues lasted to the end. Thus ivermectin was prohibited when lactating.

• Journal of Korean Society of Water and Wastewater
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• v.9 no.3
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• pp.116-126
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• 1995

The purpose of this study was to investigate the removal of ammonium nitrogen by biological nitrification in raw water containing LAS using BAC. At batch teats, LAS removal by ozone followed the first order reaction, and the rate constants(k) by ozone dose 1, 3mg/min.L were $0.040min^{-1}$, $0.062min^{-1}$ respectively. Therefore, the more ozone was dosed, the higher LAS was removed The reaction between ozone and ammonium nitrogen also followed the first order, and rate constants(k) at pH7,8 and 9 were $8.9{\times}10^{-4}min-1$, $3.8{\times}10^{-3}min^{-1}$, and $2.9{\times}10^{-2}min^{-1}$ respectively at ozone dose of 3mg/min.L . Therefore, ammonium nitrogen was little removed by ozone under neutral pH of 7. The continuous flow apparatus had four sets composed of a ozone contacter and a GAC column. Through continuous filtration test for 50days, the following conclusions were derived; (1) LAS was removed 23%, 30% respectively by ozone dose 1, 3mg/L, and was not detected in all column effluents during the period of experiment. Therefore, it appeared that adsorption capacities of each column still remained. (2) Ammonium nitrogen concentration after ozone contact varied little in raw Water because pH of raw water was from 6 to 7, and was transfered to nitrite and nitrate within GAC columns as the result of staged nitrification. After 30days, nitrite was not detected in all column effluents due to biological equilbrium between nitro semonas and nitrobacter Average removals of ammonium nitrogen in each column after the lapse of 30days were the following; ${\cdot}$ column A (ozone dose 3mg/L, EBCT 9.5min): about 100% ${\cdot}$ column B (ozone dose 1mg/L, EBCT 9.5min): 91% ${\cdot}$ column C (ozone dose 3mg/L, EBCT 14.2min): about 100% ${\cdot}$ column D (ozone dose 0mg/L, EBCT 9.5min): 53% Though column A and C reached nitrification of about 100%, column C (longer EBCT than column A) was more stable than column A. (3) After backwash, nitrification reached steady state within 5 to 8 hours. Therefore, nitrification was not greatly affected by backwash. (4) According to the nitrification capacity in depth of column A, C, where 100% nitrification occured. LAS was removed within 20cm, while ammonium nitrogen required more depth to be removed by nitrification.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.1
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• pp.75-84
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• 2001

Hot gas filtration method via using ceramic filters is an evolving technology applicable to numerous industrial and air pollution control processes. Alumino silicate, organic and inorganic binders were the major raw materials in manufacturing ceramic filters. In this work, disc type ceramic filters(50$\phi$$\times$10t) were manufactured by vacuum forming processes using ceramic raw materials. The porosity and bulk density of disc type ceramic filers ranged from 86 to 89% and from 0.27 to 0.36 g/㎤, respectively. In this work disc type ceramic medium were tested utilizing coupon experimental apparatus. Disc type filters showed high collection efficiencies over 99.96% with Darchs law coefficients of 4.1$\times$10(sup)10~9.63$\times$10(sup)10/$m^2$ depending on mean pore sizes. In addition, filtration and detachment of ceramic filters turned out to be performed effectively using 10 cm/sec face velocity, 5 minutes filtration cycle, 100msec pulse jet valve opening time and 3 bar pulsing pressure.

• Journal of Environmental Health Sciences
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• v.21 no.2
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• pp.36-41
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• 1995

In order to treat effectively various type of wastewater discharged from the manufacture factory of organic phosphorous agricultural pesticides by the activated sludge process. The acclimation test of sludge was carried out by the dilution of completely mixed raw wastewater. The results of experiment were obstained as follows. 1. The moderate dilution rate of mixed raw wastewater was founded to about 30 times. 2. The available range of BOD-SS loading was 0.1~0.15 $kg\cdot BOD/kg\cdot SS\cdot day$ and it was similar to the case of extended aeration activated sludge process. 3. After the acclimation of activated sludge, the concentration of MLSS was 2000 mg/L, removal efficiency of BOD more than 90%, and SVI 100, respectively. 4. The oxygen respiratory rate of acclimated sludge was $47 mg\cdot O_2/g\cdot hr$ and this was increased about 5 times than $10 mg\cdot O_2/g\cdot hr$ of ordinary sludge.