• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.203-209
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• 1994

The bacterial strain which utilizes phenol and degrade TCE was isolated from an industrial waste site. The bacterial strain was named as T5-7 and identified as an Acinetobacter species. After phenol-induction, the strain T5-7 removed TCE efficiently without cell growth. So, it seems that TCE degradation was not related to cell growth. TCE degradation increased when initial cell concentrations of phenol-grown T5-7 were high. In the presence of phenol, initial degradation of TCE was delayed but total amount of degradation was not affected at final stage. The strain cultured in 0.1% yeast extract did not degrade TCE, which indicates that phenol induction was essential to the TCE degradation.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.3
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• pp.453-461
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• 2012

The degradation characteristics of TCE by Ferrate(VI) oxidation have been studied. Ferrate(VI) were prepared by electrochemical method. The degradation efficiency of TCE in aqueous solution was investigated at various pH values, Ferrate(VI) doses and aqueous solution temperature values. GC-ECD was used to analyze TCE. TCE was degraded rapidly by ferrate(VI) in aqueous solution, Also, the experimental results showed that TCE removal efficiency increased with the increase of Ferrate(VI) doses. The effect of pH was investigated and the maximum degradation efficiency was obtained at pH 7. And intermediate products were identified by GC-MS techniques. Ethyl Chloride, Dichloroethylene, Chloroform, 1,1-dichloropropene, Trichloroacetic acid and Trichloroethane were identified as a reaction intermediate, and $Cl^-$ was identified as an end product.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.1
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• pp.37-46
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• 2012

The degradation characteristics of TCE by Ferrate(VI) oxidation have been studied. The degradation efficiency of TCE in aqueous solution was investigated at various pH values, Ferrate(VI) doses, initial concentrations of TCE and aqueous solution temperature values. GC-ECD was used to analyze TCE. The optimum conditions of TCE degradation were obtained pH 7.0 and $25^{\circ}C$ in aqueous solution. Also, the experimental results showed that TCE removal efficiency increased with the decrease of initial concentration of TCE. And intermediate products were identified by GC-MS techniques. Ethyl Chloride, Chloroform, Ethylene, 1,2-dichloroethane and 1,1,2-trichloroethane were identified as a reaction intermediate, and $Cl^-$ was identified as an end product.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.512-515
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• 2000

A parallel reactor system which is consisted of two trickle bed reactors (TBR) was developed for the biodegradation of trichloroethylene (TCE) in waste gas stream. The reactor were packed with porous ceramic materials and Burkholderia cepacia G4 was inoculated to form biofilms. Each reactor was operated alternatively in TCE degradation or reactivation mode, and the effect of switching time on TBR performance was investigated. The MO (monooxygenase) activity during the TCE transformation decreased below 10 % within 24 hr, but could be recovered to the initial high level within 10 hr after supplying the reactivation medium supplemented with phenol as a carbon source. This shows that the parallel TBR system has a great potential for the long-term stable treatment of TCE.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.1
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• pp.124-132
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• 1998

The Korean-made passive samplers were evaluated at the working environment for field testing. Tested materials were n-hexane, toluene and trichloroethylene. The performance of passive samplers depended on types and concentrations of organic vapors. Sampling rates were not steady until certain concentrations. The optimum concentration for determination of airborne toluene by passive samplers was equal to or over 10 ppm which is 1/10 of the Korean occupational exposure limit. Optimum concentration of n-hexane was equal to and over 1 ppm which is 1/50 of Korean occupational exposure limit. But for trichloroehtylene, coefficient of variation was 53.5 %. Passive samplers may be used for determination of n-hexane. For other materials, further study on the performance of Korean-made passive samplers is required.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.140-141
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• 2002

내륙 및 임해공업단지와 관련하여 수질오염을 거론할 때 특정 공정과 연관된 오염원을 주로 지목한다. 그러나 대부분의 공업제품 생산공정에서는 금속과 기계장치의 기름과 윤활유 세척에 TCE(trichloroethylene)와 PCE(perchloroethylene)가 함유된 세척제를 많이 사용하고 있다. (중략)

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.5
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• pp.309-312
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• 2003

The transformation capacity (T$\_$c/) of Methylosinus trichosporium OB3b in the degradation of ethylene chlorides was determined by measuring the decrease of soluble methane monooxygenase (sMMO) activity of resting cells in batch experiments. All measurements of sMMO activity were taken in the presence of 20 mM formate to avoid the deficiency of reducing power, and within 2 hrs to avoid the effect of natural inactivation from instability of the resting cells. The constant T$\_$c/ values of 0.58 ${\pm}$ 0.132 and 0.80 ${\pm}$ 0.17 ${\mu}$mol/mg cell were obtained for trichloroethylene (TCE) and 1,2-dichloroethylene (cis and trans-1,2-DCE), respectively, regardless of their concentrations. The transformation capacity measured by this method can be used to predict the amount of cells that should be stimulated in in-situ bioremediation.

• Carbon letters
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• v.11 no.1
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• pp.13-21
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• 2010

Coconut shell activated carbon (CSAC) was investigated for its ability in the removal of two neutral chlorinated organic compounds, namely trichloroethylene (TCE) and dichloromethane (DCM) from aqueous solution using a packed bed column. The efficiency of the prepared activated carbon was also compared with a commercial activated carbon (CAC). The important design parameters such as flow rate and bed height were studied. In all the cases the lowest flow rate (5 mL/min) and the highest bed height (25 cm) resulted in maximum uptake and per cent removal. The experimental data were analysed using bed depth service time model (BDST) and Thomas model. The regeneration experiments including about five adsorption-desorption cycles were conducted. The suitable elutant selected from batch regeneration experiments (25% isopropyl alcohol) was used to desorb the loaded activated carbon in each cycle.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.E
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• pp.382-389
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• 1993

An evaluation of a plasma reactor was conducted to investigate its potential as a feasible and economical off-gas control technology for an air stripping tower (AST). The plasma reactor was powered by an alternating current with frequencies up to 1000Hz. The study showed that over 90% conversion of gas-phase trichloroethylene (TCE) can be achieved. An optimum frequency for the laternating current existed for maximum power input. The optimum frequency was dependent on the reactor geometry and the primary voltage applied. for a fixed geometry, a plasma reactor has a limited capacity for flow rate. Even though it is a feasible process to control off-gases, further investigations should be conducted to develop a more economic process.

• Archives of Pharmacal Research
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• v.15 no.2
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• pp.109-114
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• 1992

For the risk assessment of human exposure to volatile halogenated hydrocarbons, a dynamic purge trap/on-column cryofocusing method using capillary gas chromatograph-$^{63}Ni$ electron capture detector and thermal desorption unit was applied to analyze the free forms, metabolites of 1, 1, 2-trichloroethylene and 1, 1, 2, 2-tetrachloroethylene. The urine sample was diluted with distilled water, hydrolyzed and sealed. Then the inert gas was infused to purge out free 1, 1, 2-trichloroethylene, free 1, 1, 2, 2-tetrachloroethylene and urichloroethanol. These compounds were trapped to $Tenax^R$ / GC-gas trap device throughout clean up tube. Being undertectable to gas chromatograph directly, trichloroacetic acid was methyl esterificated and trapped in the manner above mentioned. The optimal incubation time to get best recovery of methyl ester was 4 hours at $60^circ$C. The concentrations of free volatile halogenated hydrocarbons and their metabolites in urine were obtained of free volatile halogenated hydrocarbons and their metabolites in urine were obtained from 5 healthy volunteers. This analytical method is expected to make the biological monitoring more precise and convenient.