• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.195-198
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• 1996

In conducting systems based on LB films, TCNQ derivatives have been extensively studied as electron acceptor molecules. We have investigated the optical, electrical, and magnetic properties of Viologen-(TCNQ￣)$_2$LB films. In UV/visible absorption measurements, we have observed TCNQ￣ peak at 380 nm and dimer peak at 620 nm. The electron spin resonance measurements infer that Viologen-(TCNQ￣)$_2$LB film exhibits anisotropic properly. In other words, the LB film shows angular dependence. Iodine doping affects the degree of charge transfer and the conductivity of the films. The UV/visible absorption spectra of the LB film doped with I$_2$show peaks at near 400~430 nm and there is no dimer absorption peak. The in-plane electrical conductivity of the undoped film is approximately 4.2$\times$10$^{-6}$ S/cm.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.4
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• pp.161-164
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• 2005

Viologen has been extensively investigated in the paper because their well-behaved electrochemistry has led to their use in a variety of theses, including the electron acceptor for the electric charge delivery mediation of the devices. It was formed monolayer in QCM by self-assembly method. We could know the adsorbed mass of viologen molecules from the frequency shift. We calculated that the adsorbed mass was about 196 [$ng/cm^2$]. We studied the electron transfer property of viologen by the cyclic voltammetry among the electrochemical process so we changed an anion like 0.1 M $NaClO_4$ and $Na_3PO_4$ electrolyte solution and investigated the interrelationship between scan rate and peak current when scan rates were increased twice.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.46-50
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• 1986

Experiments with particulate fractions of Acinetobacter sp. 1 revealed that coeuzyme $Q_{10}$ is not the physiolohical electron acceptor, and that cytochromes of a, b, c, and o types are found in cells grown with carbon monoxide (CO) as the sole source of carbon and energy. It was found that cytochromes of b and o types, but not the a and c types, are functional in CO oxidation. Nicotinamide adenine dinucleotide (phosphate) is not involved in CO oxidation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1050-1053
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• 2004

Many organic materials have been synthesized and extended efforts have been made to obtain high performance electroluminescence(EL) devices, since the first report of the light-emitting diodes based on Alq3. BECCP[bis(3-N-ethylcarbazolyl)cyanoterephthalidene] is a new luminescent material having cyano as an electron acceptor part and carbazole moiety as an electron donor part. The BECCP material shows blue PL and EL spectra of the device at about 480nm and in the ITO/BECCP/Al device shows typical rectifying diode characteristics. We have introduced Alq3 between the electrode and BECCP, and obtained more intensive rectifying diode characteristics in forward and reverse bias.

• Bulletin of the Korean Chemical Society
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• v.18 no.4
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• pp.395-401
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• 1997

The substituent effects in the gas-phase rearrangement of carbenes to ketenes involved in the Wolff reaction have been investigated theoretically using the AM1 method. In the initial state, carbene, there is a relatively strong vicinal n-σ* interaction between the lone pair (n) and carbonyl group (σ*). In the bridged transition state (TS), electronic charge is transferred from the migrating ring (Z-ring) toward the nonmigrating ring (Y-ring). The carbenes are stabilized by an electron donor Y (δσY < 0) whereas the TS is stabilized by an electron acceptor Y (δσY > 0). Multiple regression analysis of log (kYZ/kHH)(=-δΔG≠/2.3RT) leads to a relatively large negative cross-interaction constant, ρYZ=-0.53, log (kYZ/kHH)=2.96 σY--1.40 σZ-0.53 σY-σZ reflecting an extensive structural change in the transition state due to the stabilization of the initial state by the vicinal n-σ* overlap. When the solvent (water) effects are accounted for by the SM2.1 model of the Cramer and Truhlar method, the magnitude of all the selectivity parameters, ρY-, ρZ and ρYZ (=-0.66) are increased.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.32 no.2
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• pp.161-164
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• 2019

This study describes the development of graphene-$TiO_2$ conjugates for the enhancement of the photocatalytic efficiency of $TiO_2$. Graphene-based hybrid nanomaterials have attracted considerable attention because of the unique and advantageous properties of graphene. In the proposed hybrid nanomaterial, graphene serves as an electron acceptor to ensure fast charge transfer. Effective charge separation can, therefore, be achieved to slow down electron-hole recombination. This results in an enhancement of the photocatalytic activity of $TiO_2$. In addition, increased adsorption and interactions with the adsorbed reagents also lead to an improvement in the photocatalytic activity of graphene-$TiO_2$ hybrid nanomaterials. The acquired result is encouraging in that the photocatalytic activity of $TiO_2$ was initiated using visible light (630 nm) instead of the typical UV light.

• Bulletin of the Korean Chemical Society
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• v.19 no.2
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• pp.160-164
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• 1998

The NADH-cytochrome b5 reductase (NCBR), a mitochondrial external electron carrier, was purified from bovine heart and turnip and their properties were examined. The mitochondrial outer membranes separated were subjected to NCBR isolation through DEAE-Cellulose ion exchange, DEAE-Sephadex gel chromatography, and hydroxyapatite adsorption chromatography. These processes yielded the purification folds of 88 and 42 and the recovery percentages of 0.2%, 5.67% for turnip and bovine heart, respectively. The molecular weight of the NCBR from the two sources was estimated to be 35,000 using SDS polyacrylamide gel electrophoresis. The Michaelis constant Km and maximum velocity Vmax were determined by measuring the NADH-ferricyanide redox system as well as the NADPH-ferricyanide redox system. The kinetics showed that both NCBRs had higher affinities for NADH than artificial electron-acceptor substrate ferricyanide. Although NADPH had a lower affinity for the enzymes than NADH, this study showed the 2'-phosphate dinucleotide could be used as a substrate.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2025-2030
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• 2010

When $Cu^{2+}$ was used as an electron acceptor, removal of $Cu^{2+}$ was achieved from the synthesized wastewater (SW) in the cathode compartment of a microbial fuel cell (MFC). By addition of $KNO_3$, the different initial pH of the SW showed no effect on the removal efficiency of $Cu^{2+}$. For $Cu^{2+}$ concentration of 50 mg/L the removal efficiencies were found to be 99.82%, 99.95%, 99.58%, and 99.97% for the $KNO_3$ concentrations of 0, 50, 100 and 200 mM, and to be 99.4%, 99.9%, 99.7%, and 99.7% for pH values of 2, 3, 4, and 5, respectively. More than 99% $Cu^{2+}$ was removed for the $Cu^{2+}$ concentrations of 10, 50, and 100 mg/L, while only 60.1% of $Cu^{2+}$ was removed for the initial concentration of 200 mg/L (pH 3). The maximum power density was affected by both $KNO_3$ concentration and initial concentration of $Cu^{2+}$. It was increased by a factor of 1.5 (from 96.2 to 143.6 mW/$m^2$) when the $KNO_3$ concentration was increased from 0 to 200 mM (50 mg/L $Cu^{2+}$), and by a factor of 2.7 (from 118 to 319 mW/$m^2$) when $Cu^{2+}$ concentration was increased from 10 to 200 mg/L (pH 3).

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.861-867
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• 2000

The feasibility of simultaneous phosphorus and nitrogen removal by enhancing anoxic phosphorus uptake was investigated in a sequencing batch reactor (SBR). By introducing an anoxic phase into an anaerobic-aerobic SBR (AO SBR), significant amounts of denitrifying phosphorus accumulating organisms (DPAOs) which can utilize nitrate as electron acceptor could be accumulated in the reactor (anaerobic-aerobic- anoxic-aerobic SBR, $(AO)_2$ SBR). A direct comparison of phosphorus uptake rate under anaerobic and aerobic conditions showed that the fraction of DPAOs in P-removing sludge were increased from 10% in the AO SBR to 64% in $(AO)_2$ SBR. The $(AO)_2$ SBR showed stable phosphorus and nitrogen removal efficiency: average removal efficiencies of TOC, total nitrogen, and phosphorus were 92%, 88%, and 100%. respectively. Results of the $(AO)_2$ SBR operation and batch tests showed that nitrite (up to 10 mg-N/L) was not detrimental to anoxic phosphorus uptake and could serve as good electron acceptor like nitrate.

• Korean Journal of Environmental Agriculture
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• v.42 no.3
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• pp.253-258
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• 2023

In the environment, chromium often exists in a highly mobile and toxic form of Cr(VI). Therefore, the reduction of Cr(VI) to less toxic Cr(III) is considered an effective remediation strategy for Cr(VI)-contamination. In this study, the biological reduction of hexavalent chromium was examined at the concentrations of 0.01 mM, 0.1 mM, and 1 mM Cr(VI) by the dissimilatory metal-reducing bacterium, Shewanella sp. HN-41 in the presence of ferric-citrate. With the relatively condensed cell densities, the aqueous phase Cr(VI) was reduced at the proportions of 42%, 23%, and 31%, respectively for the 0.01 mM, 0.1 mM, and 1 mM Cr(VI) incubations, while Fe(III)-citrate was reduced at 95%, 88%, and 73%, respectively. Although the strain HN-41 was not considered to reduce Cr(VI) as the sole electron acceptor for anaerobic metabolism in the preliminary experiment, it has been presumed that outer-membrane c-type cytochromes such as MtrC and OmcA reduced Cr(VI) in the presence of ferric-citrate as the electron acceptor. Since this study indicated the potential of relatively high cell density for Cr(VI) reduction, it might propose a bioremediation strategy for Cr(VI) removal from contaminated waters using engineered systems such as bioreactors employing high cell growths.