• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.249-255
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• 1999

The effect of surface roughness on biodegradability of poly (3-hydroxybutyrate) was investigated. The PHB film prepared by cooling the molten polymer slowly ($-0.5^{\circ}C$/min) had higher crystallinity and melting temperature than that prepared by quenching into liquid nitrogen followed by annealing at $90^{\circ}C$ for 2 hours. However, the former sample was found to degrade faster than the latter due to presence of microscopic crack. Roughening the surface of a PHB film by hot pressing under a coarse surfaced plate accelerated the bioerosion considerably of the sample in comparison with the sample having the same thermal history but smooth surface.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.5
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• pp.262-268
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• 2015

This study established an analytical method to simultaneously determine six organophosphorous pesticides [methyldemetone-S, diazinon, fenitrothion, parathion, phentoate, and O-ethyl O-(4-nitrophenyl) phenylphosphonothioate (EPN)] and carbaryl in water using a gas chromatography/mass spectrometry (GC/MS) system coupled with on-line micro extraction by packed sorbent (MEPS) and programmed temperature vaporizer (PTV) injector. Polystyrene divinylbenzene (PDVB) was used as a sorbent of MEPS. The effects of elution solvents, pH, elution volume and draw-eject cycles of samples on sample pretreatment process were investigated. Also, quality assurance and quality control (QA/QC) and the recovery of the pesticides in environmental samples were evaluated. The elution was performed using $30{\mu}L$ of a mixed solvent (acetone : dichloromethane = 80 : 20 (v/v)). Sample pretreatment processes were optimized with seven cycles of draw-eject of sample (1 mL) spiking an internal standard and sulfuric acid. At lower pH, the analytical sensitivity of diazinon decreased, but that of carbaryl increased. The method detection limit and the limit of quantification for this method were 0.02~0.18 and $0.08{\sim}0.59{\mu}g/L$, respectively. The method precision and accuracy were 1.5~11.5% and 83.3~129.8%, respectively, at concentrations of $0.5{\sim}5.0{\mu}g/L$. The recovery rates for all the pesticides except carbaryl in various environmental samples ranged 75.7~129.3%. The recovery rate of carbaryl in effluent sample was over 200% whereas carbaryl in drinking water, groundwater, and river water were in the acceptable range.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.165-165
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• 2005

• Analytical Science and Technology
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• v.15 no.4
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• pp.381-387
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• 2002

In this study, we introduced experience participated in ELPAT (Environmental Lead for Proficiency Analytical Testing) program that is administered by the American Industrial Hygiene Association and EPA. The 126 sample results of total 128 samples met reference value, as a result accepted 'proficient'. The concentration of Pb in air, paint chips, soils and dust wipes are $0.0089{\sim}0.3956mg/m^3$, 0.0500~8.9149%, 29.0${\sim}$1697 mg/kg and $18.00{\sim}900.3{\mu}g/sample$, respectively. The lead in environmental matrix prepared adequate techniques and analysed by flame atomic absorption spectrometry. The lead in air was extracted hydrochloric acid, in paint chips and soils were digested with microwave and hotplate and in dust wipes were prepared microwave digestion. No differences of each preparation techniques was found and all methods were to be proper.

• Journal of the Korean Home Economics Association
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• v.43 no.1 s.203
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• pp.191-201
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• 2005

This study was intended to analyze the pro-environmental housing consciousness and behavior of housewives in Ulsan, Korea, according to their socioeconomic characteristics and other variables. The sample consisted of 175 housewives living in Ulsan, with descriptive analyses and multiple regressions used to analyze the aforementioned data. In general, the respondents showed high levels of pro-environmental housing consciousness and behavior. The results of the analyses indicated that the experiences of environmental education, recognition of the environment in general and pro-environmental housing consciousness were significant explanatory variables of the actual pro-environmental housing behavior. This implies that the provisions of education and information relating to the overall environment including pro-environmental housing should be emphasized.

• Journal of Veterinary Science
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• v.22 no.2
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• pp.28.1-28.6
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• 2021

An African swine fever (ASF) outbreak in wild boars was first reported on October 2, 2019, in South Korea. Since then, additional cases were reported in South Korea's border areas. We here report the identification of ASF virus (ASFV) DNAs from two out of eight environmental abiotic matter samples collected from areas where ASF-positive wild boar carcasses were found. Comparative genomic investigations suggested that the contaminating ASFV DNAs originated from the wild boar whose carcass had been found near the positive sample sites. This is the first report on the identification of ASF viral material in wild boar habitats.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.321-324
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• 2001

Groundwater samples were collected at 6 sites in Seoul area. DNA extraction from the sample was performed by the boiling method. Samples were boiled with guanidinium thyocyanate and phenol-chloroform. One set of primer was designed for amplification of 16S rDNA. For detection of denitrifying bacteria in groundwater sample, the author used primer sets consensus regions in gene sequences encoding the two forms of nitrite reductase (NIR), a key enzyme in the denitrification pathway. Two sets of PCR primer were designed to amplify $cd_1$-and Cu-nir. We confirmed the existence of denitrifying bacteria in 3 sites using $cd_1$-nir primer and in 4 sites using Cu-nir primer.

• Journal of Environmental Health Sciences
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• v.23 no.2
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• pp.28-34
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• 1997

This study was carried out to investigate the effects of prechlorination and algae growth on THMs generation. The sample water obtained from Paldang Dam which is a main source of raw water for the Seoul metropolitan area. THMs concentration in the sample water was investigated in water treatment process prechlorifiation, chemical coagulation, and sand filtration. And also, THMs concentration were analyzed in the water which cultured algae in laboratory. The results were as follows 1. The THMs concentration produced by prechlorination unit process were increased in control (not purified) but decreased in process of purification. 2. The THMs concertration can reduce by increasing the number of cleaning filters. 3. The main precursor in raw water for the THMs generation was supplied by algae growth. So as to reduce the THMs concentration in water supplying system, it is the best method to manage algae growth in water body of Paldang reservoir.

• Journal of Korean Society on Water Environment
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• v.29 no.4
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• pp.568-573
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• 2013

In this study, we conducted whole effluent toxicity (WET) proficiency testing based on the results which $EC_{50}$ value of 3 types (A, B, C) unknown samples calculated from 32 water quality measurement agencies in Korea. WET proficiency testing was expected to their improve of analysis skill and ensure reliability of analysis results. Ultimately, it is intended to promote the reliable enforcement of WET. WET proficiency testing was evaluated using the z-score, robust z-score and the results showed that 30 participating agencies were "compliance". In addition, $EC_{50}$ values of "unknown sample A" were the normal distribution. Therefore, "unknown sample A" was considered as the most suitable standard toxicity substance.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.42-49
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• 2004

The study was carried out in order to improve the quality of fermented soybean, that is, Doenjang with strain ,mold and bactea, added mulberry leaves powder were investigated and analyzed as follows. 1. The water content of samples was 38.51-50.10%, pH value 5.44-6.21 and total acidity, 2.42-3.13 2. The reducing sugar of content for samples was 7.01-7.24% on contrast mulberry added sample was 8.34-12.11%, Amino-N as contrast 5.96-7.63% mulberry added, 8.34-12.11% 3. In sensory evaluation test, excellent results was 2% added sample than others. 4. The heaby metals analyzed form samples cans, iron, tin and lead content of samples were 5.63-6.03 ppm, 31.70-35.53 ppm and trace.