• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.255-259
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• 2004

본 연구에서는 유류오염 토양현장샘플을 이용한 실험실 규모의 회분식 실험을 통해 다양한 환원조건하에서 BTEX와 MTBE의 자연정화 평가 및 현장 생복원 기술 적용 타당성을 검토하는데 있다. 첫째, 오염토양과 비오염 토양에서 충분한 전자수용체의 존재는 유류오염물질의 생분해능을 증가시킬 수 있었음 알았다. 둘째, 같은 토양이라도 전자수용체의 종류와 유류오염물질의 특성에 따른 생분해능의 다양성을 확인할 수 있었다. 셋째, BTEX에 비해 MTBE의 분해가 매우 느림을 확인하였다. 본 실험은 아직 초기 단계의 실험으로 현장 조건을 충분히 만족 시키지는 못한다. 추가적인 pH 변화에 따른 전자수용체의 이용 특성 및 토양-지하수 microcosm test, 혐기성 생분해 부산물인 $CO_2$, $N_2$ 또는 $N_2$O, TBA의 연구가 실시되어야 하겠다.

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.176-180
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• 1995

To characterize expression and formation of three type crystal proteins in transformant, Bacillus thruingiensis PT0529 was analysed by transmission electron microscope and SDS-PAGE according to growth. The results showed that the introduced crystal protein genes, rcyIVD and cytA, were well expressed at earlier stage than resident crystal proteins were also expressed with their own morphology. However, resident crystal protein of B. thuringiensis PT0529 was smaller than that of wild type B. thuringiensis NT0423, suggesting that resident crystal protein production was interfered with introduced two type crystal protein genes.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.151-157
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• 2005

A one-dimensional numerical model was developed to simulate vertical profiles of electron acceptors and their reduced species in benthic sediments. The model accounted for microbial degradation of organic matter and subsequent chemical reactions of interest using stoichiometric relationships. Depending on the dominant electron acceptors utilized by microorganisms, the benthic sediments were assumed to be vertically subdivided into six zones: (1) aerobic respiration, (2) denitrification, (3) manganese reduction, (4) iron reduction, (5) sulfate reduction, and (6) methanogenesis. The utilizations of electron acceptors in the biologically mediated oxidation of organic matter were represented by Monod-type expression. The mass balance equations formulated for the reactive transport of organic matter, electron acceptors, and their corresponding reduced species in the sediments were solved utilizing an iterative multistep numerical method. The ability of model to simulate a freshwater sediments system was tested by comparing simulation results against published data obtained from lake sediments. The simulation results reasonably agreed with field measurements for most species, except for ammonia. This result showed that the C/N ratio (106/16) in the sediments is lower than what the Redfield formula prescribes. Since accurate estimates of vertical profiles of electron acceptors and their reduced species are important to determine the mobility and bioavailability of trace metals in the sediments, the model has potential application to assess the stability of selected trace metals in the sediments.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.938-943
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• 2007

Anaerobic degradation of petroleum hydrocarbons in a soil artificially contaminated with 10,000 mg/kg soil of diesel fuel was tested by adding an anaerobic sludge taken from a sludge digestion tank. Treatments of soil(50 g) with 15 mL/kg soil and 30 mL/kg soil of the digestion sludge(2,000 mg/L of vss(volatile suspended solids)) showed 37.2% and 58.0% of total petroleum hydrocarbons(TPH) removal during 90 days incubation, respectively. In evaluation of several anaerobic conditions including nitrate reducing, sulfate reducing, methanogenic, and mixed electron accepters condition, treatments with the digested sludge showed significant degradation of diesel fuel under all anaerobic conditions compare to a control treatment of soil without the sludge and a treatment of autoclaved soil treatment with autoclaved digestion sludge. The rate of diesel fuel degradation was the highest in the treatment with the sludge and mixed electron accepters (75% removal of TPH) for 120 days incubation followed in order by sulfate reducing, nitrate reducing, methanogenic condition as 67%, 53%, 43%, respectively. However, the removal rate of non-biodegradable isoprenoid was the highest in the sulfate reducing condition. These results suggest that anaerobic degradation of diesel fuel in soil with digested sludge is effective for practical remediation of soil contaminated with petroleum hydrocarbons.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.175-180
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• 2003

Microbial Fe(III) reduction is an important factor for biogeochemical cycle in anaerobic environments, especially sediment of freshwater such as lakes, ponds and rivers. In addition, the Fe(III) reduction serves as a model for potential mechanisms for the oxidation of organic compounds and the reduction of toxic heavy metals, such as chrome or uranium. Shewanella putrefaciens DK-1 was a gram-negative, facultative anaerobic Fe(III) reducer and used ferric ion as a terminal electron acceptor for the oxidation of organic compounds to $CO_{2}$ or other oxidized metabolites. The ability of reducing activity and utilization of various electron acceptors and donors for S. putrefaciens DK-1 were investigated. S. putrefaciens DK-1 was capable of using a wide variety of electron acceptor, including $NO_{3}^{-}$, Fe(III), AQDS, and Mn(IV). However, its ability to utilize electron donors was limited. Lactate and formate were used as electron donors but acetate and toluene were not used. Fe(III) reduction of S. putrefaciens DK-l was inhibited by the presence of either $NO_{3}^{-}$ or $NO_{2}^{-}$. Further S. putrefaciens DK-1 used humic acid as an electron acceptor and humic acid was re-oxidized by nitrate. Environmental samples showing the Fe(III)-reducing activity were used to investigate effects of the limiting factors such as carbon, nitrogen and phosphorus on the Fe(III) reducing bacteria. The highest Fe (III) reducing activity was measured, when lactate as a carbon source and S. putrefaciens DK-1 as an Fe(III) reducer added in untreated sediment samples of Cheon-ho and Dae-ho reservoirs.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11b
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• pp.49-50
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• 2003

본 실험은 An-Ax 조건에서 $NO_3$ loading에 변화를 주면서 DNPAOs의 존재 유무를 확인하고 과연 이 미생물이 무산소조에서 이 PHA를 탄소원으로 인섭취를 할 수 있는지의 여부를 조사하고자 수행하였다. 유입 $NO_3$농도에 따라 전체를 4개의 case로 분류하여 실험을 수행하였다. case I에서는 인섭취가 43.68 mg/day로 거의 일어나지 않았는데 이는 전자수용체로서 $NO_3$가 부족했기 때문 이였다. 다음 caseII에서는 333.36 mg/day로 인섭취량이 많이 증가하였고 case III, IV에서는 각각 447.48, 428.64 mg/day로 거의 일정해졌다. 이를 통해 전자수용체로 $NO_3$를 이용하는 DNPAOs가 존재함을 분명히 알 수 있었고 또한 이 미생물이 최적으로 P 섭취를 할 수 있는 유입 $NO_3$농도는 본 실험 조건에서 는 20mg/L였다.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.1
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• pp.43-47
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• 2020

A novel series of adamantyl derivatives of N-aryl amides as androgen receptor antagonists were synthesized and their anti-androgenic activities were evaluated. The N-aryl amides containing adamantyl derivatives had more activity than those lacking adamantyl substitutions. The synergistic effect of bulkiness of the adamantyl group and modulation of electron density on the aromatic ring by pendant groups was crucial to the potent antagonism. Molecular modeling studies were performed to elucidate the interactions between ligands and receptors.

• Transactions of the Korean hydrogen and new energy society
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• v.2 no.1
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• pp.7-13
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• 1990

We are interested in studying the artificial photolysis of water which mimics the natural plant photosynthesis. In the artificial system there should be a proper photosensitizer, electron donor and electron acceptor. Since Mn-tetramer is known to be the essential part for the oxygten-evolving system in the natural photosynthesis, it is important to know or study the reactivity of Mn-porphyrins. As a model for the Mn-tetramer in the natural photosynthesis, we prepared the lipophilic and hydrophilic Mn-porphyrins. For the lipophilic porphyrin with long hydrocarbon chain, the long hydrocarbon chain was inserted in the porphyrin ring formation step. For the hydrophilic porphyrin, the porphyrin was sulfonated with sulfuric acid. These syntheses of lipophilic and hydrophilic Mn-porphyrins are significant, since the behaviors of these compounds will be different in the microemulsions or vesicles. We also found that the Mn-porphyrins were photoreduced in the microemulsion and water in the presence of amines.

• Journal of Chest Surgery
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• v.36 no.2
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• pp.109-112
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• 2003

Stromal tumors of the gastrointestinal tract, especially of the esophagus, are rare. We had a case of malignant gastrointestinal stromal tumor(GIST) of the esophagus. A 46 years old woman was admitted for abnormal mass shadow in the chest radiograph. The mass was originated from the lower thoracic esophagus, and compressed the right lower pulmonary vein and the inferior vena cava. We removed the tumor externally without injuring of the esophageal mucosa via right posterolateral thoracotomy. The tumor was positive for CD 34 and CD 117, and diagnosed malignant CIST of the esophagus.

• Applied Biological Chemistry
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• v.17 no.2
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• pp.143-148
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• 1974

The interaction of the carcinogenic mycotoxin, Aflatoxin $B_1$, with the electron-donating molecule, benzene, was studied spectrophotometrically. The formation of charge-transfer complex between Aflatoxin $B_1$ and benzene in the presence of zinc chloride was observed and the apparent equilibrium constant of this charge-transfer complex was found to be 0.198 (liter $mole^{-1}$). It is assumed that, as the result of this study, some charge-transfer complexes could be formed between the weak electron-accepting Aflatoxin $B_1$ and strong electron-donating molecules, and the spectral changes occurred in the binding of Aflatoxin $B_1$ with proteins or DNA is attributed to the existence of charge-transfer type interaction.