• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1999년도 추계학술발표회
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• pp.19-22
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• 1999

A microbial consortium derived from a gasoline-contaminated sites was enriched on toluene in 100-mL serum bottle and was found to degrade benzene(B), toluene(T), ethylbenzene(EB), and xylenes(X). Studies conducted to determine the temperature effects and BTEX concentration on BTEX degradation. The results indicated that lowering temperature significantly decreased BTEX degradation rates and varing the BTEX concentration also changed substrate degradation patterns.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.364-367
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• 2003

In this paper, we have examined the MTBE cometabolic degradation by pure culture, which is isolated gasoline contaminated aquifer. Propane was more effectively utilized as a growth substrate to oxidize MTBE. Specific substrate degradation rate was Increased with increasing initial propane amount. Respiking propane was enhanced and continued MTBE degradation and TBA observation was supported MTBE degradation. The mass balance of MTBE and TBA indicated that MTBE was oxidized to TBA as well as further oxidation of TBA.

• 한국환경농학회지
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• 제1권1호
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• pp.65-70
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• 1982

담수토양(湛水土壤)에 IBP 입제(粒劑)를 반부처리(反復處理)하고 후처리(後處理)한 약제(藥劑)의 분해(分解)에 미치는 영향(影響)을 시험(試驗)한 결과(結果) 1) IBP의 반부처리(反復處理)로 후처리(後處理)한 IBP의 분해(分解)가 촉진(促進)되었으며 그 효과(效果)는 약 53일간지속(日間 持續)되었으나 diazinon의 분해(分解)에는 영향(影響)이 없었다. 2) 토양살균(土壤殺菌)으로 IBP의 분해(分解)가 크게 억제(抑制)되어 분해속도(分解速度)는 무살균토양(無殺菌土壤)에 비해 3배(倍)이상 지연(遲延)되었으며 반부처리(反復處理)에 의해 생성(生成)된 IBP 분해촉진능력(分解促進能力)도 소실(消失)되었다. 3) IBP 반부처리(反復處理)로 인(因)한 토양미생물(土壤微生物)의 전체 colony수(數)는 변하지 않았다.

• KSBB Journal
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• 제25권1호
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• pp.103-107
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• 2010

Oil degradation agent was developed with organic sludge and modified peat moss (MPM) to recover oil contaminated soil. Waste sludge discharged from wastewater treatment plant of chemical plant in Ulsan National Industrial Park was used as organic sludge, and MPM was purchased. Organic sludge was adequate to use as growth medium for microorganism, the surface of MPM had porous structure which could enhance the cultivation condition of oil degradation microorganisms. Water contents and TPH variation with time were observed to investigate the degradation capacity of developed degradation agent. Water contents were rapidly decreased with higher contents of MPM, however, in case of TPH, high MPM content decreased the degradation capacity. Therefore, it was recommended that the content of MPM was controlled to below 10% in degradation agent as mixing organic sludge with MPM.

• 농약과학회지
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• 제14권4호
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• pp.332-338
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• 2010

살충제 diazinon의 토양 중 가축분뇨 및 그 시비량에 따른 분해특성을 알아보고자 밭토양과 논토양 20 g에 돈분액비(RPS; raw pig slurry)와 가공돈분액비(PPS; processed pig slurrry)를 기준량, 2배량 및 3배량 수준으로 가한 후 diazinon 0.5mg/kg을 처리하고 60일 동안 항온배양($25{\pm}2^{\circ}C$, 암조건)하면서 시간경과에 따른 농약의 분해양상 및 반감기를 조사하였다. 액비를 처리하지 않은 밭토양과 논토양에서의 diazinon 반감기는 각각 28, 22일 정도로 나타났다. Diazinon은 액비의 종류와 상관없이 밭토양보다 논토양에서 약 $5.0{\pm}1.2$일 가량 짧은 반감기를 보여 논토양에서 가수분해에 의한 분해도 일어남을 유추할 수 있었다. 밭토양, 논토양 모두 PPS 처리구보다 RPS 처리구에서 diazinon이 더욱 빠르게 분해되었으며, 비료의 시비량이 많을수록 그 분해가 빠르게 나타나 더 짧은 반감기를 보였다. 이러한 결과는 토양수분함량 및 액비의 처리에 의한 유기물함량 변화가 diazinon의 분해에 영향을 미친다는 것을 확인할 수 있었다.

• 한국환경과학회지
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• 제16권11호
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• pp.1247-1255
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• 2007

Soil biofiltration is an environmentally-sound technology for elimination of VOCs, odorous and $NO_X$ compounds from a low concentration, high volume waste gas streams because of its simplicity and cost-effectiveness. This study investigated the optimal mixture fraction of briquet ash, compost, soil and loess for $NO_X$ degradation. Extreme vertices design was used to examine the role of four components on $NO_X$ degradation. Under our experimental conditions, 74.5% of $NO_X$ degradation was observed, using a model mixture(25% briquet ash, 10% compost, 30% soil and 40% loess) containing 100 ppb of NO. It was shown that experimental design analysis could allow selecting optimal conditions in such biodegradation processes in this study.

• 한국환경농학회지
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• 제16권4호
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• pp.341-346
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• 1997

퇴비, 화학비료, 중금속, 합성세제를 첨가한 토양중 살균제 oxadixyl의 분해성에 대하여 연구한 결과를 요약하면 다음과 같다. 토양중 oxadixyl은 매우 느리게 분해가 진행되는 lag phase후에 분해가 빨라졌으며 분해 반감기는 10.5일이었다. 퇴비 첨가는 oxadixyl의 분해를 크게 촉진시켰다. Oxadixyl의 분해는 칼리 첨가에 의하여 크게 촉진되었으나 질소와 인산에 의하여는 거의 영향을 받지 않았다. 토양중 oxadixyl의 분해는 중금속 첨가에 의하여 억제되었으며 억제 정도는 Ni이 가장 컸으며 다음은 Cd, Cr, Cu, Zn순이었다. 합성 세제 첨가 또한 oxadixyl의 분해를 억제시켰다. 각종 물질을 첨가한 토양중에서 oxadixyl의 분해율은 토양의 microbial biomass나 호흡률과 높은 정의 상관 관계를 보여 각종 첨가 물질이 oxadixyl의 분해를 촉진 혹은 억제하는 것은 이들 첨가 물질이 분해 미생물의 생육을 촉진 또는 억제하였기 때문으로 판단되었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.360-363
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• 2003

Bioremediation is often used for in situ remediation of petroleum-contaminated site. We studied the microbial degradation of hydrocarbon in an artificially diesel contaminated soil in laboratory microcosm. In control soil, about 30% of the initial TPH was diminished and the degradation of diesel oil was significantly enhanced by the addition of bioremediation agent (70% of TPH reduction).

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.89-91
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• 2000

Polynuclear aromatic hydrocarbon (PAH) compounds are highly carcinogenic chemicals and common groundwater contaminants that are observed to persist in soils. The adherence and slow release of PAHs in soil is an obstacle to remediation and complicates the assessment of cleanup standards and risks. Biological degradation of PAHs in soil has been an area of active research because biological treatment may be less costly than conventional pumping technologies or excavation and thermal treatment. Biological degradation also offers the advantage to transform PAHs into non-toxic products such as biomass and carbon dioxide. Ample evidence exists for aerobic biodegradation of PAHs and many bacteria capable of degrading PAHs have been isolated and characterized. However, the microbial degradation of PAHs in sediments is impaired due to the anaerobic conditions that result from the typically high oxygen demand of the organic material present in the soil, the low solubility of oxygen in water, and the slow mass transfer of oxygen from overlying water to the soil environment. For these reasons, anaerobic microbial degradation technologies could help alleviate sediment PAH contamination and offer significant advantages for cost-efficient in-situ treatment. But very little is known about the potential for anaerobic degradation of PAHs in field soils. The objectives of this research were to assess: (1) the potential for biodegradation of PAH in field aged soils under denitrification conditions, (2) to assess the potential for biodegradation of naphthalene in soil microcosms under denitrifying conditions, and (3) to assess for the existence of microorganisms in field sediments capable of degrading naphthalene via denitrification. Two kinds of soils were used in this research: Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS). Results presented in this seminar indicate possible degradation of PAHs in soil under denitrifying conditions. During the two months of anaerobic degradation, total PAH removal was modest probably due to both the low availability of the PAHs and competition with other more easily degradable sources of carbon in the sediments. For both Harbor Point sediment (HPS-2) and Milwaukee Harbor sediment (MHS), PAH reduction was confined to 3- and 4-ring PAHs. Comparing PAH reductions during two months of aerobic and anaerobic biotreatment of MHS, it was found that extent of PAHreduction for anaerobic treatment was compatible with that for aerobic treatment. Interestingly, removal of PAHs from sediment particle classes (by size and density) followed similar trends for aerobic and anaerobic treatment of MHS. The majority of the PAHs removed during biotreatment came from the clay/silt fraction. In an earlier study it was shown that PAHs associated with the clay/silt fraction in MHS were more available than PAHs associated with coal-derived fraction. Therefore, although total PAH reductions were small, the removal of PAHs from the more easily available sediment fraction (clay/silt) may result in a significant environmental benefit owing to a reduction in total PAH bioavailability. By using naphthalene as a model PAH compound, biodegradation of naphthalene under denitrifying condition was assessed in microcosms containing MHS. Naphthalene spiked into MHS was degraded below detection limit within 20 days with the accompanying reduction of nitrate. With repeated addition of naphthalene and nitrate, naphthalene degradation under nitrate reducing conditions was stable over one month. Nitrite, one of the intermediates of denitrification was detected during the incubation. Also the denitrification activity of the enrichment culture from MHS slurries was verified by monitoring the production of nitrogen gas in solid fluorescence denitrification medium. Microorganisms capable of degrading naphthalene via denitrification were isolated from this enrichment culture.

• 농약과학회지
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• 제4권3호
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• pp.1-6
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• 2000

광조건 및 토양중에서 제초제 dicamba의 분해특성을 조사하기 위하여 자연광 조건과 물리화학성이 다른 2종류의 토양을 선택하여 수행하였다. 광조건하에서 dicamba의 분해율은 처리 9주후에 3.3%였으며, 주분해산물로써 4-hydroxy dicamba가 검출되었고, 또한 기존에 알려진 분해산물인 5-hydroxy dicamba도 확인되었다. 한편 Dicamba는 살균되지 않은 토양에서 배양 8주후에 $14.7{\sim}23.2%$가 분해되었으며, 토양중 dicamba 분해경로는 주로 탈메칠 (demethylation) 작용에 의해 이루어졌다. 또한 살균된 토양에서 dicamba 분해는 아주 서서히 되는 것으로 보아 dicamba 분해에는 미생물이 주로 작용하는 것으로 나타났다.