• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.374-377
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• 2016

• Bulletin of the Korean Chemical Society
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• v.22 no.3
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• pp.257-258
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• 2001

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.311-315
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• 2005

When paraquat was added to the bacterial membrane or mitochondrial suspension, the mixture turned dark blue, but the color was disappeared by aeration. The same phenomenon was seen when electrons were supplied to the paraquat. Blue color appeared from near the cathode, and then spreaded to whole transit system. Coloration was accelerated by addition of alkali, but the color was reduced by addition of acid or oxygen. Paraquat exhibited absorption at ultraviolet region by electron transfer at the concentrations as low as 1.0 mM which did not exert difficulty in showing color reaction. Paraquat caused the increase of the optical density at 340 nm by electron transit, and an aspect of that had a strong resemblance to NADH. The acute toxic action of paraquat seemes to depend on inhibition of energy metabolism cased by paraquat action of electron donor and acceptor.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.3052-3058
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• 2014

In this article, we have designed and synthesized a novel donor-${\pi}$-acceptor (D-${\pi}$-A) type porphyrin-based sensitizer (denoted UI-5), in which a carboxyl anchoring group and a 9,9-dimethyl fluorene were introduced at the meso-positions of porphyrin ring via phenylethynyl and ethynyl bridging units, respectively. Long alkoxy chains in ortho-positions of the phenyls were supposed to reduce the degree of dye aggregation, which tends to affect electron injection yield in a photovoltaic cell. The cyclic voltammetry was employed to determine the band gap of UI-5 to be 1.41 eV based on the HOMO and LUMO energy levels, which were estimated by the onset oxidation and reduction potentials. The incident monochromatic photon-to-current conversion efficiency of the UI-5 DSSC assembled with double-layer (20 nm-sized $TiO_2$/400 nm-sized $TiO_2$) film electrodes appeared lower upon overall ranges of the excitation wavelengths, but exhibited a higher value over the NIR ranges (${\lambda}$ = 650-700 nm) compared to the common reference sensitizer N719. The UI-5-sensitized cell yielded a relatively poor device performance with an overall conversion efficiency of 0.74% with a short circuit photocurrent density of $3.05mA/cm^2$, an open circuit voltage of 0.54 mV and a fill factor of 0.44 under the standard global air mass (AM 1.5) solar conditions. However, our report about the synthesis and the photovoltaic characteristics of a porphyrin-based sensitizer in a D-${\pi}$-A structure demonstrated a significant complex relationship between the sensitizer structure and the cell performance.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.2
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• pp.75-85
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• 2016

A pyrotechnic system consisting of donor/acceptor pair separated by a gap relies on shock attenuation characteristics of the gap material and shock sensitivity of the donor and acceptor charges. Despite of its common use, numerical study of such pyrotechnic train configuration is seldom reported because proper modeling of the full process requires precise capturing of the shock wave attenuation in the gap prior to triggering a full detonation of high explosive and accurate description of the high strain rate dynamics of the explosively loaded inert confinements. We apply a Eulerian level-set based multimaterial hydrocode with reactive flow models for pentolite donor and heavily aluminized RDX as acceptor charge. The complex shock interaction, critical gap thickness, acoustic impedance, and go/no-go characteristics of the gap test are quantitatively investigated.

• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1337-1341
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• 1998

The charge transfer (CT) complex dyes between electron donor phenothiazine and electron acceptors namely, 2, 3-dichloro-1,4-naphtoquinone and 2,3-dichloro-5-nitro-1,4-naphtoquinone, were formed in the dichloromethane solution and electrochromic properties were studied using Bu4NC1O4 as supporting electrolyte. A 1 : 1 correspondence between the donor and acceptor molecules in the CT complex was found.

• Coupled systems mechanics
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• v.6 no.1
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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.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.2083-2086
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• 2011

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.309-310
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• 2007

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.33.1-33
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• 2002