• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1229-1232
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• 2014

• Advances in materials Research
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• v.9 no.2
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• pp.155-170
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• 2020

In this paper, using the recently introduced analytical approach for the analysis of mass and heat transfer during film growth in reactors for epitaxy from the gas phase, these processes are analyzed taking into account natural convection and the possibility of changing the rate of chemical interaction between reagents. As a result of the analysis, the conditions under which the homogeneity of the grown epitaxial layers increases with a change in the values of the parameters of the growth process are formulated.

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.971-975
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• 1994

Cross sections and recoil properties have been measured for the fragments produced in the interaction of silver with 40 MeV/nucleon $^{14}N$ ions using off-line ${\gamma}$-ray spectroscopy. The data were used to obtain the isobaric-yield distribution, the mass yield distribution, and the fractional momentum transfer. The values of forward-to-backward ratios were measured to be very large, indicating that substantial momentum transfer occurs at this energy regime. The results are compared with other studies of the interaction of silver with intermediate-energy heavy ions.

• Bulletin of the Korean Chemical Society
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• v.14 no.4
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• pp.465-468
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• 1993

Four compounds containing two 2,2,6,6-tetramethylpiperidin-1-yloxyl radicals were synthesized. They are all chemically bonded with squaric moieties. The diradical compounds show fundamentally the paramagnetic behaviors satisfying the theoretical magnetic susceptibility according to Curie's law. A diradical compound of salf-form 4 however shows a relatively strong antiferromagnetic interaction in comparison with other reported organic radicals. The antiferromagnetic interaction of diradical 4 approximates a value of J/k= -50 K by the theoretical analysis of its temperature dependence.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.630-634
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• 1995

The cluster distributions for different concentrations of 1,4-dibromonaphthalene (DBN) in 4,4'-dibromobenzophenone (DBBP)/1,4-dibromonaphthalene (DBN) choleic acid were determined by a computer simulation in order to model the energy transfer dynamics. The results of the simulation indicate that long range interaction between molecules further apart than nearest does not occur and energy transfer efficiency is restricted by single range interaction. The results also demonstrate that the trapping is diffusion limited. The energy transfer rate is reduced by a factor of 15 in DBBP/DBN choleic acid realtive to that in DBBP/DBN doped into polystyrene due to the larger distance between molecules.

• Journal of the Korean Magnetic Resonance Society
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• v.22 no.4
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• pp.125-131
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• 2018

Chemical shift perturbation (CSP) is a simple NMR technique for studying binding of a protein to various ligands. CSP is the only technique that can directly provide both a value for the dissociation constant and a binding site from the same set of measurements. To accurately analyze the CSP data, the exact binding mode such as multiple binding, should be carefully considered. In this review, we analyzed systematically the CSP data with multiple modes. This analysis might provide insight into the mechanism on how proteins selectively recognize their target ligands to achieve the biological function.

• Bulletin of the Korean Chemical Society
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• v.5 no.6
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• pp.245-248
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• 1984

Raman spectroscopy was used to study the reorientational motion of hexafluorobenzene in benzene and also in neutral solvents. From the viscosity dependence of the reorientation time, intermolecular interaction in the systems was investigated. No evidence was found to support the presence of long-lived 1:1 complex of hexafluorobenzene and benzene. The unusual viscosity dependence of the reorientational motion observed in the systems was explained as due to the formation of transient complexes.

• Bulletin of the Korean Chemical Society
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• v.9 no.5
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• pp.308-311
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• 1988

The hydrophobic interaction occurring between rhodamine 6G and tetraphenylborate was investigated spectroscopically by varying the medium with the addition of surfactants or ethanol. The ion aggregates formed between the two ions were destroyed by the additives. The dye existed as monomeric species in the presence of a cationic surfactant whereas it was incorporated with anionic and nonionic surfactants. For the complete dissociation more than the critical micelle concentration (cmc) was required with a nonionic surfactant while less than cmc was necessary with the others.

• Bulletin of the Korean Chemical Society
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• v.10 no.4
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• pp.346-348
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• 1989

Interactions between Tl atoms for the Tl dimer are studied by relativistic and nonrelativistic EHT methods. Relativistic bond weakening for the Tl dimer is qualitatively explained by comparing orbital energies from relativistic and nonrelativistic calculations. It is also shown that significant overlap exists, especially for 6p orbitals, at the internuclear distance larger than 4 ${\AA}$, implying that Tl-Tl interaction is not just the electrostatic interaction in the recently discovered dimeric thallacarborane.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.709-716
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• 2015

In this study, structural developments of polypropylene / ionomer / clay ternary composites were investigated depending on the dispersion and localization of clay. The changes in physical properties were observed adding organoclays 1~10wt% to 90% polypropylene and 10% ionomer blends. The organoclays were localized inside of the dispersed phase under the composition of 3wt%, however, over that composition, clay particles formed stiff network structure in the dispersed phase and additional clays were localized at the interface between two phases. According to the developments of microstructure, the interaction of ternary composites changed from polypropylene-ionomer to polypropylene-ionomer and ionomer-clay which affected rheological properties. The storage modulus (G') of the composites was similar to the blends when clays were localized inside of dispersed phase but increased when clays were localized at interface. Also, the fractured morphology of the composites showed phase boundary and growing radius of dispersed phase depending on addition of fillers when clays were found inside. However, when fillers found at the interface between blends, the radius of the dispersed phase decreased and compatibilized morphology were observed. The interfacial interaction of the ternary composite was quantified depending on the structural development of dispersed phase and localization of clay particles by the rheological properties. The interaction of composites at solid state which was measured through peel adhesion strength increased by growth of interfacial interaction of each component. Furthermore, the crystallinity of the composites was decreased when the clay particles were localized at the interface.