• Bulletin of the Korean Chemical Society
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• 제33권4호
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• pp.1190-1198
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• 2012

Three hydroquinone dimethyl ether derivatives have been synthesized and characterized by X-ray diffraction. The electron donating properties were evaluated by using UV-vis spectroscopy, cyclic voltammetry and by ESR spectroscopy. The microcrystalline cation-radical salts of the three donor molecules were also isolated by using antimony pentachloride, a single electron Lewis acid oxidant.

• KSBB Journal
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• 제11권2호
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• pp.211-217
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• 1996

난분해성 물질로 알려진 2,4,6-trichlorophenol를 혐기성 미생물의 cometabolism을 이용하여 처리할 경우 높은 탈염소화 속도를 얻기 위하여 전자콩여체 를 선정하기 위하여 회분식 실험을 수행하였다. 회분식 실험은 Serum bottle에서 중량천 폐수처리장 의 1차 소화조에서 채취한 혐기성 소화슬러지를 사 용하여 2,4,6-trichlorophen이의 환원척 탈염소화 반 응을 유도하였다. 탈염소화 과정에셔 중간생성물을 조사하였고 혐기성 미생물의 성장과 유지를 위한 에 너지원인 전자공여체에 따른 탈염소화 속도를 비교 하였다. 회분식 실험결과 2,4,6 - trichlorophenol은 ortho위치의 염소가 치환되어 2,4- Oichlorophenol 로 탈염소화되 었다2,4-dichlorophenol은 다시 ortho위치의 염소가 치환되어 4-chlorophenol로 탈 염소화되 었다. Acetate, ethanol, glucose와 metha nol를 전자공여 체로 사용한 결과 ethanol을 사용한 경우에 서 2,4,6-trichlorophenol의 탈염소화 속도가 가장 빠른 것으로 관찰되었다.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1391-1396
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• 2014

In the present study, ten metal free non-linear optical (NLO) compounds have been designed. These compounds have designed by structural modification of (2-cyano-5-(4-(phenyl(4-vinylphenyl)amino)phenyl) penta-2,4-dienoic acid (TC4). Density functional theory was used for structure optimization and determination of photo-physical properties. These compounds contain triphenylamine as electron-donor and cyanoacrylic acid as acceptor. Five ${\pi}$-spacers are used to connect the donor and acceptor. Two auxiliary donors are also used to assist the donor. Results of this study indicate that stronger electron-donating auxiliary groups and longer ${\pi}$-conjugation enhance NLO response. Major absorption peaks of all systems were in the visible region. These absorption peaks are associated with the ${\pi}-{\pi}^*$ transitions of the entire molecule. From calculations it is clear that all system will be good NLO material. The present calculations will provide new ways for experimentalists to synthesize high-performance NLO material.

• Bulletin of the Korean Chemical Society
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• 제15권6호
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• pp.436-442
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• 1994

Heterobimetallic complexes have a donor-accepter metal-metal bond in which two electrons from the electron-rich metal moiety are donated to the other electron-deficient one. Based on the competition reactions, Cotton-Kraihanzel force constants, ν(CO)IR band resolution and the relative nucleophilicity comparison of the donor ligands, the following relative ligating ability of the donor ligands toward $M(CO)_5$ (M=Cr, W) is assessed: cis-HW$(CO)_4P(OMe)_3^-$, $HW(CO)_5^-$ > $HCr(CO)_5^-$-$Br^-$ > trans-HFe$(CO)_3P(OMe)_3^-$ > $Mn(CO)_5^-$ > $HFe(CO)_4^-$ > PP$h_3$

• 대한환경공학회지
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• 제28권3호
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• pp.292-299
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• 2006

전자공여체로 벤조산염을 이용한 perchloroethene(PCE)의 환원성 탈염소화 과정에서 전자공여체의 첨가량 및 초기 미생물 식종량이 탈염소화에 미치는 영향을 평가하기 위하여 회분식 실험을 수행하였다. 벤조산염이 탈염소화를 위한 양론비 이하(전자공여체/수용체 비=0.5와 1)로 첨가된 경우 탈염소화 효율은 벤조산염 첨가량이 증가함에 따라 71%에서 94.3%로 증가하였으나, 탈염소화에 이용된 전자공여체의 분율은 92.7%에서 79.6%로 감소하였다. 메탄생성은 PCE와 trichloroethene(TCE)가 모두 cis-1,2-dichloroethene(cDCE)으로 전환된 후 문턱농도(threshold value, 10 nM) 이상으로 수소농도가 유지되는 동안 진행되었다. 벤조산염이 양론비 이상으로 첨가된 경우 탈염소화 완료 후 잔존하는 수소는 메탄생성량을 증가시켰다. 식종 미생물량의 증가는 지체기를 감소시켰지만 최대 탈염소화 속도는 벤조산염 분해 속도에 의해 결정되어 식종 미생물량에 큰 영향을 받지 않았다. 식종 미생물 농도가 높은 경우 초기 활발한 탈염소화로 인하여 메탄생성량은 감소하고, 탈염소화 효율은 증가하였다.

• Environmental Engineering Research
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• 제16권4호
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• pp.213-218
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• 2011

The two-stage intermittent aeration activated sludge process (IAP) and dynamic-flow intermittent aeration activated sludge process (DFP) were investigated for the nutrient removal of domestic wastewater. Three sets of IAP and one set of DFP were operated. The fermented settled sludge taken from the primary settling tank was added to two IAP and one DFP as an external electron donor, with one IAP, in which an external carbon source was not added, as a control. All the systems were operated at a sludge retention time of 20 days and a hydraulic retention time of 12 hr. A Higher denitrification rate was observed with the fermented settled sludge for the denitrification compared to the process without the addition of the organic source. The result indicates that the fermented acid from the primary domestic sludge has been proved to be an excellent electron donor for denitrification and biological phosphorus removal with IAP and DFP in treating relatively low C/N ratio(Carbon / Nitrogen ratio) wastewater. Phosphate accumulating organisms have a capability of competing with denitrifiers in the presence of volatile organic acids under anoxic conditions.

• Journal of Microbiology
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• 제35권3호
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• pp.206-212
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• 1997

Heliobacillus mobilis is a strictly anaerobic Gram-positive bacterium which contains a primitive Photosystem I-type reaction center. The membrane-bound cytochrome $C_{553}$ from the heliobacterium suggested to be the immediate electron donor to the photooxidized pigment (P798+) has been isolated and characterized. The heme protein was visualized as a major component with an apparent molecular size of 17kDa in TMBZ-staining analysis of the membrane preparation and showed characteristic $\alpha$ (552.5 nm), $\beta$ (522nm), and Soret absorption (416 nm) peaks of a typical reduced c-type cytochrome in the partially purified sample. The internal 43 amino acid sequence of the electron donor was obtained by chemical agent and protease treatments followed by N-terminal sequencing of the resulting fragments. The internal sequence carries lots of lysine residues and a Cys-X-X-Cys-His sequence motif which are the characteristics of typical c-type cytochromes. The analysis of the sequence by FAST or FASTA program, however, did not show any significant similarity to other known heme proteins.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.432.2-432.2
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• 2016

A new A-D-A type (Acceptor-Donor-Acceptor) conjugated based on pyridine-borane complex (Donor), non-boron fluorine (Donor) and 2,5-bis(alkyl)-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DPP) (Acceptor) were designed and synthesized via Pd-catalyzed Suzuki cross-coupling reaction. The synthesized boron based complex exhibited high electron affinity, which indicates deep HOMO energy levels and good visible absorption led to their use as donors in BHJ (bulk heterojunction) solar cells. Inverted devices were fabricated, reaching open-circuit voltage as high as 0.91eV. To probe structure-property relationship and search for design principle, we have synthesized pyridine-boron based electron donating small molecules. In this study, we report a new synthetic approach, molecular structure, charge carrier mobility and morphology of blended film and their correlation with the photovoltaic J-V characteristics in details.

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권2호
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• pp.22-37
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• 2006

생물벽체(biobarrier) 또는 원위치 미생물 필터(in situ microbial filter) 기술을 이용한 염소계 유기용매로 오염된 지하수의 복원 가능성을 회분식 실험을 통하여 살펴보았다. PCE의 환원성 탈염소화의 효율과 속도는 수소 농도에 의존하는 것으로 알려져 있다. 본 연구에서는 분변토와 토탄을 생물벽체로 이용한 PCE의 환원성 탈염소화시 전자공여체의 영향을 살펴보았다. 유기산(lactate, butyrate benzoate)과 yeast extract, 비타민 $B_{12}$가 PCE의 환원성 탈염소화에 미치는 영향을 조사하였다. 생물벽체 담체 비존재시, 전자공여체를 투여하지 않은 control 실험에 비해, 전자공여체의 첨가는 PCE의 탈염소화 속도를 촉진하였다. 전자공여체를 투여한 실험 중에서 lactate 또는 lactate/benzoate를 수소 공여체(hydrogen donor)로 첨가된 경우, 탈염소화 속도가 가장 빨랐다($k_1=0.0260{\sim}0.0266\;day^{-1}$). 분변토를 생물벽체로 사용한 경우, lactate/benzoate 첨가시 탈염소화 속도가 가장 빨랐으며, 겉보기 1차 분해속도상수($k_1$)는 $0.0849day^{-1}$였다. 반면, Pahokee peat을 생물벽체로 사용하였을 경우, butyrate 또는 lactate의 첨가시 탈염소화 속도가 가장 빨랐으며 $k_1$ 값은 각각 0.1092, $0.1067\;day^{-1}$로 나타났다. 본 연구결과로부터 분변토 또는 토탄을 원위치 생물벽체로 사용하여 염소계 유기용매로 오염된 지하수 처리의 잠재적인 응용 가능성을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1706-1710
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• 2005

The excited-state intramolecular proton transfer (ESIPT) fluorescence in the 2-(2'-hydroxyphenyl)benzoxazole (HBO) derivatives with different electron donor and acceptor substituents was studied by spectroscopic and theoretical methods. Changes in the electronic transition, energy levels, and orbital diagrams of HBO analogues were investigated by the semi-empirical molecular orbital calculation and were correlated with the experimental spectral position of ESIPT keto emission. It was found that the presence of substituents, regardless of their nature, resulted in the red-shifted absorption relative to HBO. However, the spectral change of the ESIPT fluorescence was differently affected by the nature of substituent: hypsochromic shift with electron donor and bathochromic shift with electron acceptor.