• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 1991년도 춘계학술대회 학술대회 프로그램
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• pp.8-12
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• 1991

탈질 박테리아를 이용한 사염화탄소의 분해 실험에서 electron donor의 공급이 중단되면 사염화탄소의 제거율이 낮아지고, 반면 electron acceptor의 주입이 중단되면 제거율이 높아졌다. 사염화탄소의 제거시 클로로폼이 생산되어 사염화탄소가 환원되고 있음을 보여 주었다. 이 결과는 사염화탄소가 일종의 electron acceptor로 작용하면서 전자를 얻기 위해 세포 내의 다른 electron acceptor와 경쟁한다는 가설을 뒷받침한다. 호기성 박테리아에 의해서도 실험조건하에서 상당량(25∼30%)의 사염화탄소가 제거되었다. Electron acceptor의 공급중단에는 영향을 받지 않았다. 그러나 사염화탄소의 제거와 함께 클로로폼이 형성되므로써 사염화탄소의 환원분해가 호기성 상태에서도 진행될 수 있음을 보여 주었다.

• Environmental Analysis Health and Toxicology
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• 제6권3_4호
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• pp.149-154
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• 1991

Biodegradation of carbon tetrachloride (CTC) in denitrifying and aerobic columns was investigated under various conditions of electron-acceptor and electron-donor availability. CTC removal increased when the electron-acceptor (nitrate) injection was stopped in the denitrifying column; however, CTC remova1 decreased when electron donor (acetate) was deleted in the denitrifying and the aerobic column. Small fractions of the CTC removed appeared as chloroform, indicating that reductive dechlorination of CTC was occurring. The results from the denitrifying column support the hypothesis that CTC behaves as an electron acceptor that competes for the pool of available electrons inside the bacterial cells.

• Bulletin of the Korean Chemical Society
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• 제24권5호
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• pp.569-572
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• 2003

The majority of dyes belong to the chromophoric class known as donor-acceptor systems. The essential structural feature of such systems is the presence of one or more electron donating groups conjugated to one or more electron withdrawing groups via an unsaturated bridge. The pyrazolin-5-one system is an effective electron acceptor residue, and can also act as a weak electron donor. In our experiments, the various symmetrical and unsymmetrical H-chromophores were synthesized in the indoxyl, imidazo[1,2-a]pyridin-2-one, pyrazolin-5-one, and pyridin-2,6-dione residues, resulting in cross-conjugated donor-acceptor systems. And the visible light absorption was then associated with the migration of electron density from the donor region of the molecule to the acceptor region. Also, it was useful to prepare related non-cross-conjugated donor acceptor chromophores by combining these residues with other electron donor or acceptor moieties. For convenience such chromophores are referred to as merocyanines.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1098-1104
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• 2014

New electron deficient acceptor-acceptor-acceptor type of monomer unit composed of weak electron accepting benzimidazole and relatively strong electron accepting benzothiadiazole derivatives namely 4,7-bis(6-bromo-1-(2-ethylhexyl)-1H-benzo[d]imidazol-2-yl)benzo[c][1,2,5]thiadiazole (BBB) was synthesized. The Stille polycondensation of the newly synthesized BBB monomer with electron donating 2,6-bis(trimethyltin)-4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene (BDT) afforded donor-acceptor-acceptor-acceptor type of polymer namely 2,6-(4,8-bis(2-ethylhexyloxy)benzo[1,2-b:4,5-b']dithiophene)-alt-4,7-bis(1-(2-ethylhexyl)-1H-benzo[d]imidazol-2-yl)benzo[c][1,2,5]thiadiazole (PBDTBBB). The opto-electrical studies revealed that the absorption band of PBDTBBB appeared in the range of 300 nm-525 nm and its highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels were positioned at -5.18 eV and -2.84 eV, respectively. The power conversion efficiency (PCE) of the polymer solar cell (PSC) prepared from PBDTBBB:PC71BM (1:2 wt %) blend was 1.90%.

• 대한화학회지
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• 제11권4호
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• pp.126-131
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• 1967

各 種 아민(triethylamine, diethylamine, pyridine, diphenylamine, dimethylaniline)과 各種 Electron Acceptor($CCl_4,\;ICl,\;I_2$)를 Hexane 溶媒 存在下에서 作用시킨 結果 各各 Charge Transfer Complex를 形成하였으나 그 形成能은 아민의 Basicity에 比例하였고 Electron Donor의 Polarity의 差가 클 때에는 다른 形式의 Complex를 形成함을 紫外線 吸收 分光法으로 確認하였다. Complex 形成能과 아민의 Basicity 및 Electron Acceptor의 Polarity의 關係를 論하였다.

• 한국미생물·생명공학회지
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• 제31권2호
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• pp.197-200
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• 2003

In oil-contaminated environments, anaerobic biodegradation of toluene depended on the concentration and distribution of terminal electron acceptor as well as the physicochemical properties such as DO concentration, redox potential and pH. This study showed the anaerobic biodegradation of toluene in two different soils by using nitrate reduction, ferric iron reduction, sulfate reduction and methanogensis. Toluene degradation rates in the soil samples taken from rice filed and tidal mud flat by nitrate reduction were higher than those by other processes. Tho soil samples from the two fields were enriched for 130 days by providing toluene as a sole carbon source and nitrate or sulfate as a terminal electron acceptor. The toluene degradation rates in the enriched denitrifying consortia obtained from the rice field and tidal mud flat soil were 310.7 and 200.6 $\mu$mol$ L^{-1}$ / $d^{-1}$, respectively. The toluene (legradation rates in the enriched sulfate-reducing consortia from the fields ranged fi-om 149.1 to 86.1$\mu$mol $L^{-1}$ / $d^{-1}$ .

• 한국전기전자재료학회논문지
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• 제35권4호
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• pp.366-371
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• 2022

Recently many efforts have been made to develop a novel class of non-fullerene electron acceptor materials for high-performance organic solar cells. In this work, anthraquinone derivatives, TMAQ and THAQ, were prepared and their availability as electron acceptor materials for organic solar cells were investigated in terms of optical, thermal, electrochemical properties, and solar cell devices. Compared to TMAQ, a significant bathochromic shift of absorption band was observed for THAQ owing to intramolecular hydrogen-bond-assisted CT interactions. Thanks to the fused aromatic ring structure and benzoquinone unit, both TMAQ and THAQ exhibited a high thermal stability and an efficient electron reduction process. In particular, the intramolecular O-H---O=C hydrogen bond of THAQ plays an important role in improving the thermal stability and electron reduction properties. In the P3HT:acceptor solar cell system, THAQ-based devices had more than ca. 6 times higher power conversion efficiency than TMAQ -based devices. These results serve as a guide for developing high-efficient anthraquinone-based electron acceptor materials.

• Coupled systems mechanics
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• 제6권1호
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• pp.75-96
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• 2017

As electron donor/acceptor materials for organic photovoltaic cells, small-molecules donors/acceptor are attracting more and more attention. In this work, we investigated the electronic structures, electrochemical properties, and charge carrier transport properties of four recently-synthesized small-molecule donors/acceptor, namely, DPDCPB (A), DPDCTB (B), DTDCPB (A1), and DTDCTB (B1), by a series of ab initio calculations. The calculations look into the electronic structure of singly oxidized and reduced molecules, the first anodic and cathodic potentials, and the electrochemical gaps. Results of our calculations were in accord with those from experiments. Using Marcus theory, we also computed the reorganization energies of hole/electron hoppings, as well as hole/electron transfer integrals of multiple possible molecular dimer configurations. Our calculations indicated that the electron/hole transport properties are very sensitive to the relative separations/orientations between neighboring molecules. Due to high reorganization energies for electron hopping, the hole mobilities in the molecular crystals are at least an order of magnitude higher than the electron mobilities.

• Journal of Photoscience
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• 제7권1호
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• pp.1-4
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• 2000

The photosensory ciliates Blepharisma japonicum and Stentor coeruleus use the hypericin-derived pigments blepharismin and stentorin, respectively, as photoreceptor chromophores. Fluorescence quenching studies have shown that the first excited singlet state of hypericin and the purified chromophores blepharismin and stentorin can be deactivated by electron transfer to an acceptor molecule with a suitable reducing potential [1,2]. This paper reports the result of a series of photobehavioral experiments performed with the aim to ascertain if the same electron accepters which quench the photoreceptor pigment fluorescence in vitro may also compete with the native acceptor molecule in its natural physiological environment. Individual cell trajectories were examined before and after light stimulation, in the presence and in the absence of potential "in vivo" electron accepters, with a microvideo-recording apparatus. Our data, on Blepharisma cells, showed that as the negative reduction potential of the electron acceptor increases, a pronounced decrease in cell photoresponsiveness was detected. A dramatic effect on cell photoresponsiveness was noticed in the presence of 1,4-benzoquinone that has the lowest negative reduction potential. Such an effect on the percentage of photoreacting cells was moderate in the case of 1,4-naphthoquinone, with a relatively higher negative reduction potential. In the presence of benzophenone, which has the highest negative reduction potential, no significant effect on photoreacting cells was noticed. Our results can support the hypothesis that in the pigment granules such a light-induced charge transfer from excited blepharismin to a suitable electron acceptor triggers sensory transduction processes in B. japonicum.

• Journal of Microbiology
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• 제39권4호
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• pp.273-278
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• 2001

Shewanela, putrefaciene IR-1 and MR-1 were cultivated by using various combinations electron donor-acceptor, lactate-Fe(III) lactate-nitrate, pyruvate-FE(III), pyruvate-nitrate H$_2$ acetate-Fe(III) and H$_2$-acetate-nitrate. Both strains grew fermentatively on pyruvate and lactate but not on without and electron acceptor. In culture with Fe(III), both astrains grew on pyruvate and lactate but on H$_2$-acetate- CO$_2$. In cultivation with nitrate, both stains grew on pyruvate lactage and on H$_2$-acetate-CO$_2$ The growth yields of IR-1 pyruvate, pyruvate-Fe(III) and lactate-Fe(III) were about 3.4, 3.5, and 3.6(g cell/M substrate), respectively. From the growth properties of both strains on media with Fe(III) as an electron acceptor, the bacterial growth was confirmed not to be increased by addition of Fee(III) as an electron acceptor to the growth medium, which indicates a possibility that the dissimilatory reduction of Fe(III) to Fe(III) may not be coupled to free energy production.