• Journal of the Korean Society of Groundwater Environment
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• v.4 no.1
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• pp.14-19
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• 1997

Laboratory experiments were conducted to study the effects of pH and salt level on the soil sorption equilibrium of pentachlorophenol (PCP) which is hydrophobic and ionogenic. Experimental results indicated that the sorption equilibrium constant (Kp) of PCP increased with decreasing pH. A quantitative sorption model involving linear isotherms was estabilished to predict the pH effect on the PCP sorption equilibrium over the pH range from 3 to 8. The model prediction was in good agreement with the experimental data. Also, the Kp increased with salt concentration over the entire pH range. At added salt levels less than 0.1M, increase in Kp was larger than when the added levels were higher than 0.1M. Salt might increase the PCP sorption by inducing 'salting out-effect' or by forming deprotonated PCP-cation ion pairs such as PCP$\^$-/K$\^$＋/. Taking the pH range (5-8) and the salt content (up to 50 g/L) in the groundwater of Metropolitan landfill sites into consideration, the results indicated that the retardation factor of PCP in this area might range from 3 to 550 depending upon pH and salt content.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.133-142
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• 2004

The purpose of this study is to evaluate a laboratory test on arsenic removal effciency for ARD(Acid Rock Drain-age) using limestone and apatite, and on heavy metals removal efficiencies for AMD(Acid Mine Drainage) using apatite and fish bone. As a result of the laboratory test, pH, arsenic removal rate of limestone & apatite are inversely proportional to flow rates and apatite removes 100% of arsenic while limestone removes 37% of arsenic at 0.6$m{ell}$/min/kg flow rate in case of ARD treatment. And the dissolution amount of apatite is twenty five times higher than that of limestone. In case of AMD treatment, fish bone shows higher dissolution rate than apatite, and pH of outlet water reacted with fish bone is higher than that reacted with apatite. The heavy metal removal rates of fish bone are also higher than that of apatite except arsenic removal rate. The precipitate resulted from fish bone reaction with AMD seems to be biological sludge type while that resulted from apatite with AMD is inorganic solid which can settle easily compared with the biological sludge and can be cemented by gypsum. As the results, apatite can be used as a precipitant for the polluted mine waters showing wide range of pH and fish bone can be used for highly contaminated AMD.

• Applied Biological Chemistry
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• v.40 no.1
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• pp.65-70
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• 1997

Among 980 fungal strains isolated from the lesions of Trifolium repens L. and various weeds, three Penicillium sp. F40362, F40496, F40497 were selected by the first selection test and a pathogenicity test. The spores of these strains germinated readily 90 to 100% and readily infected the respective plant. The wheat bran-corn starch formulation of F40362 strain showed 100% mycoherbicidal activity against clover plant at $4{\times}10^8$ spores/pot. The same formulations of F40496 and F40497 strains showed 100% mycoherbicidal activity against clover plant at $12{\times}10^8{\sim}4{\times}10^8$ spores/pot. The same formulations of tee strains showed over 30% mycoherbicidal activity against Leguminosae plants. This method of pelletiation was potentially useful for the production of inoculum formulation as mycoherbicides and it was effective enough to treat $2{\sim}2.5\;g$ formulation($4.5{\times}10^7\;spores/mg$) to a $350\;cm^2$ pot. The three strains, F40362, F40496 and F40497 have selective mycoherbicidal activity between Trifolium repens L. and Zoysia japonica and nonselective mycoherbicidal activities against some other crop plants and weeds.

• Journal of Environmental Science International
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• v.19 no.12
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• pp.1343-1354
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• 2010

The purpose of the study was to analyze the persistence of HCH in atmosphere, soil, sediment and water of the western and southern regions of Korea. The samples from the western region were collected from Anmyeon Island, and the samples from the southern region were collected from Kimhae and Busan. The concentration of HCH isomers in atmosphere showed the pattern of $\alpha$-HCH>$\gamma$-HCH>$\beta$-HCH. The regions with high HCH concentration in the atmosphere are the regions that have been highly exposed to HCH used in the past, and the areas that have been influenced by the long range transport. The HCH that persists in the soil, water and sediment evaporates into the atmosphere, showing the characteristics of Air-Surface exchange. When the regional concentration distributions are compared, the concentration of HCH was higher in the atmosphere of a plain and the cities near the plain, than the urban areas. In this study, the ratio of $\alpha/\beta$-HCH was used as an indicator for estimating the source of Technical HCH and Lindane. According to the result, the contribution of Lindane was high in Kimhae plain and Kimhae urban areas. However, in Busan, the contribution of Technical HCH was higher than Lindane. In case of Anmyeon Island, the western region of Korea had high contribution from Tehcnical HCH. In soil and sediment, $\beta$-HCH was dominant. In water, $\gamma$-HCH was dominant among other isomers. Such results are due to $\gamma$-HCH inLindane. Furthermore, the source of $\gamma$-HCH in urban areas is assumed to be the use of medicine, medical supplies and other living supplies. Based on the results of this study, the management of HCH, a newly list up emerging POPs, should be strengthened by further research on sources, fate, persistency, accumulation and exposures and etc. to the risk assessments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1486-1491
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• 2004

The estrogenicities of six heavy metal compounds, which contaminate frequently in foods, were assayed using a combination of in vitro and in vivo assays. The assays were 1) estrogen receptor dependent transcriptional expression assay, 2) E-screen assay and, 3) the uterotropic assay in mice. The chemicals studied were 17$\beta$ -estradiol, diethylstilbestrol (DES), arsenic oxide, bis(tri-n-butyltin), cadmium chloride, chromium chloride, lead acetate, and mercuric chloride. Using the estrogen receptor dependent transcriptional expression assay, the following estrogenicity ranking was measured: bis(tri-n-butyltin) > cadmium chloride > chromium chloride >> mercuric chloride >lead acetate = arsenic oxide. Using E-screen test, the following estrogenicity ranking was measured: bis(tri-n-butyltin) > cadmium chloride > chromium chloride >> mercuric chloride > lead acetate = arsenic oxide. Results from the uterotropic assay showed that bis(tri-n-butyltin), cadmium chloride, chromium chloride caused an increase in uterine wet weight, while lead acetate, mercuric chloride, and arsenic oxide failed to do so. Bis(tri-n-butyltin), cadmium chloride and chromium chloride showed the highest estrogenicity in three assay systems. Recent studies suggesting that bis(tri-n-butyltin), cadmium chloride have estrogenicities are compatible with the present finding. Furthermore, our study is suggesting that chromium chloride may be estrogenic. The results demonstrate that this three level-assay combination (transcriptional activation, cell proliferation, and an in vivo effect in an estrogen-responsive tissue) could serve as a useful method to assess the estrogenicity of heavy metals.

• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.368-377
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• 2012

This study evaluated the water quality of Yeongsan River by multivariate analysis using the data collected during 2001~2010. Water quality in Yeongsan River could be explained up to 75.2% by four factors, which were included in loading of nutrients (32.021%) and organic matters (17.453%), seasonal variation (14.775%) and microbes (10.951%). The results of cluster analysis were classified into three groups by factor 1 and 2, which has different water quality characteristics. Group 1 included sampling stations located in the upper stream and estuary dyke of Yeongsan River, group 2 included Gwangju 1 and Gwangsan affected by domestic sewage of Gwangju-cheon, and group 3 included sampling stations located in the midstream around the livestock farm and farmland.

• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.91-96
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• 2004

It is generally believed that amino acids occurring naturally in mammals are of the L-configuration. D-amino acid(DM) are common in nature as constituents of bacterial cell walls and several antibiotics. Recent reports have demonstrated the presence of small amounts of free DM in milk. The presence of free DM may affect the food quality by decreasing the nutritional value. Our objective was to examine whether the free DM carne from psychrotrophic bacteria. Free DM was produced by treating raw milk with Pseudomonas spp. The samples were extracted with sulphosalicylic acid and derivatized with AccQ-$Tag^{TM}$ reagent when the analysis was carried out by reverse-phase HPLC. We tested correlations of the content of free DM with bacterial growth. Significant amounts of free D-a1anine and D-proline have been found in the raw milk inoculated with Pseudomonas spp. The increase of D-alanine and D-proline appeared to be mainly related to the presence of Pseudomonas fluorescens. These results suggest that free DM may be considered as an indicator of psychrotrophic bacterial milk contamination.

• Journal of Food Hygiene and Safety
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• v.28 no.3
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• pp.227-233
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• 2013

In this study, we evaluated the ability of various disinfectants to suppress the growth of microorganisms in fresh-cut products and organic vegetable. The growth of more than 50% of B. cereus isolates were suppressed by 50% ethanol, 0.1% hydrogen peroxide, 0.4% sodium hypochlorite or 1% calcium oxide. E. coli generally showed high susceptibility to concentration of 10% ethanol, 0.4% sodium hypochlorite and 1% calcium oxide. Eighty percent or more of S. aureus isolates exhibited resistance to ethanol, hydrogen peroxide and sodium hypochlorite, but the isolates were susceptible to concentrations of 1% calcium oxide. All isolates evaluated in this study were sensitive to benzalkonium chloride (BAC) and growth in the presence of $2.0{\mu}g/mL$ of BAC was completely inhibited. These pathogens showed widely different susceptibilities to different organic acids. Greater than 0.5% acetic acid and 2% and higher concentrations of malic acid and tartaric acid inhibited the growth of 60% of the isolates of B. cereus. Two percent acetic acid and tartaric acid inhibited 50% of the S. aureus isolates. Seventy percent of the E. coli isolates were resistant to malic acid and susceptible to 1% acetic acid and 10% tartaric acid. The antibacterial effects of the various sanitizers evaluated in this study were not only dependent on the type of disinfectant but also on the pathogen. Thus, it is important to select a sanitizer that is safe and effective at removing specific types of microorganisms.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.3
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• pp.188-195
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• 2009

Generally. mobile sources of air pollution were classified in on-road and non-road. Due to increased registration number of construction equipment in Korea. updated emission factors for non-road mobile sources, such as construction machinery. should be developed. NONROAD model of U.S. EPA already has introduced transient adjustment factors and sulfur adjustment factors for emission factors of diesel powered engine. In addition to this. European Environment Agency (EEA) has proposed emission factors for off-road machinery including several types of construction equipment. In this study. six types of construction equipment, such as excavator. forklift, loader, crane, roller and bulldozer, were studied to estimate emission factors based on total registration status in Korea. Total 445 construction equipments between 2004 and 2007 model year were tested with KC1-8 mode and air pollutants (CO, THC, $NO_x$, and PM) were measured. After statistical estimation and calculation, emission factors for CO, THC, $NO_x$, and PM for excavator, forklift, loader, crane, roller and bulldozer were provided and compared with previous emission factors. Moreover, updated emission factors for six types of construction equipment in this study were verified after comparison with emission factors of U.S. EPA. Finally, estimated emission amounts of four air pollutants were suggested according to six types of construction equipment.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.6
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• pp.555-568
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• 2014

The construction equipment is one of the major sources for hazardous air pollutants in Korea, and the its management has been of great concern recently. The objective of this study was to estimate each contribution of emission of construction equipments according to their production year, electric power consumption and type. To achieve this goal, we developed pollutant emission factors for the machineries manufactured after 2009, which are excluded from the present framework of Korean air pollutants inventory, CAPSS. More than 800 data obtained from emission investigations were utilized for the estimation. Compared with the previous estimation, the scheme used this study was modified to incorporate new emission factors as well as to include the corresponding activity data. Such improvement allow us to gain more detailed emission informations which are better characterized by specifications of construction equipments. The total amount of pollutants emitted from construction equipments in 2011 were estimated as 126.8, 7.0, 58.3, and 17.0 kton for $NO_x$, PM, CO, and VOC, respectively. The estimation results indicate that the increase in the emission of equipments is significantly related to their age and power consumption. The emissions of the older ones manufactured from 1992~1996 were estimated to be the contribution ranged from 23.7% to 26.8%, whereas the newer ones (2009~2011) showed the attributions of 11.3~21.5%. In addition, the results show that the emission of each equipment was increased with the increase in the electric power consumption of engine, probably due to their average output power. Among the nine types of machinery compared, excavators and forklifts were investigated to contribute relatively higher emissions in the level of 39.8~44.0% and 32.0~34.2%, respectively.