• Journal of the Korean institute of surface engineering
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• v.36 no.1
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• pp.74-78
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• 2003

The corrosion failure of electronic devices has been a major reliability concern lately. This failure is an ongoing concern because of miniaturization of integrated circuits (IC) and the increased use of polymers in electronic packaging. Recently, plasma-polymerized cyclohexane films were considered as a possible candidate for a interlayer dielectric for multilever metallization of ultra large scale integrated (ULSI) semiconductor devices. In this paper the protective ability of above films as a function of deposition temperature and RF power in an 3.5 wt.% NaCl solution were examined by polarization measurement. The film was characterized by FTIR spectroscopy and contact angle measurement. The protective efficiency of the film increased with increasing deposition temperature and RF power, which induced the higher degree of cross-linking and hydrophobicity of the films.

• Applied Chemistry for Engineering
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• v.22 no.4
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• pp.390-394
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• 2011

Vapor liquid equilibria were measured for the binary systems of ditetrahydrofurfurylpropane (DTHFP) and some solvents such as cyclohexane, n-heptane, tetrahydrofuran, and water. Binary vapor liquid equilibria were measured for the diluted concentration range of DTHFP. NRTL model was used to analyze the measured data. With the experimental data, binary interaction parameters of the NRTL model were regressed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.4
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• pp.383-390
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• 2014

The following conclusion was made from the 2D-QSAR model for the tyrosinase inhibitory activity according to the variation of the substituents R1 and R2 in analogues of compound 2-[(2,6-dioxocyclohexyl)methyl]cyclohexane- 1,3-dione (1-23). The best optimized 2D-QSAR model was $Obs.pI_{50}=-0.295({\pm}0.031)TDM$ $-0.120({\pm}0.014)DMZ+0.135({\pm}0.050)DMX.R_2+6.382({\pm}0.17)$, and the correlation $r^2=0.905$) of which was greater than its predictability ($q^2=0.843$). The magnitude of the effect of tyrosinase inhibitory activities was in order of TDM > $DMX.R_2{\geq}DMZ$, and it tended to increase as the hydrophobicity of substrate molecule (ClogP > 0) as well as the steric favor of substituent $R_1$ increased. The analysis of the model implies that inhibitory activity of substrate molecule will increase as $DMX.R_2$ (Dipole moment X component of $R_2$-substituent) increases, while TDM (Total Dipole Moment) and DMZ(Dipole Moment of Z-Component) decrease. As such, it is deemed feasible to conclude, that in order to increase the inhibitory effect, it would be rather desirable to replace the polar groups within the molecules with non-polar functional groups.

• Bulletin of the Korean Chemical Society
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• v.15 no.12
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• pp.1129-1131
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• 1994

• Journal of Photoscience
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• v.9 no.2
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• pp.353-355
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• 2002

We prepared 3-(1-hydroxyethyl)-bacteriopyrochlorophy11-a (3) possessing magnesium atom and phytyl ester from modification of natural bacteriochlorophyll(BChl)-a. A dichloromethane solution of (3$^1$R) and (3$^1$S)-3 was diluted with 100~1000 fold volume of cyclohexane to give new species absorbing near-infrared lights. The resulting Q, maximum of (3$^1$R)-3 was 860 nm and red-shifted by 2150 $cm^{-1}$ / from the monomeric. In the nonpolar organic solvent, epimeric (3$^1$S)-3 showed a 1ess red-shifted peak at 798 nm as well as a residual monomeric band. Such visible spectra indicated that 3 diastereose1ectively aggregated in cyclohexane to afford oligomers possessing a simi1ar supramolecular structure with chlorosomal aggregates of natural BChl-d, 7,8-dehydro-form of 3.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.804-807
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• 1999

New copper complexes with a ligand, L(L=N,N'-cyclohexane bis(ferrocenylmethylene)amine) which was obtained from ferrocene carboxaldehyde and 1,2-diaminocyclohexane with a mole ratio of 2:1, were prepared and characterized. Those were adapted to asymmetric catalysis. The copper(II) complexes do not work in cyclopropanation of styrene and ethyl diazoacetate but copper(I) complex catalyzes. The Cu(I)LOTf (OTf=trifluorometanesulfonate) shows a good regioselectivity giving high trans to cis ratio of up to 80:20.

• Journal of Photoscience
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• v.1 no.1
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• pp.39-45
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• 1994

Haloarene in which the phenyl group and halophenyl group are connected by alkyl groups were synthesized to study the photochemical behavior. The photochemical reactions of 1-halo-2-(phenylalkyl)enzenes (1 and 2) were studied in several aerated or unaerated solvents. In the case of 2-benzyl-1-halobenzene photoreduced product (biphenyl) is major in acetonitrile or benzene. In cyclohexane or acetonitrile with triethylamine, photoreduced product is obtained exclusively, while in acetonitrile with toluene, xylene, or sodium hydroxide photocyclized product (fluorene) is mainly obtained. In the case of 1-halo-2-phenethylbenzenes (5 and 6), photocyclized product (9,10-dihydrophenanthrene and phenanthrene) are major in acetonitrile or benzene. While the haloarenes 1 or 2 connecting the two arene rings by methylene is photoreduced, the other haloarene 5 or 6 connecting by ethylene is photocyclized. In cyclohexane or acetonitrile with a small amount of triethylamine, photoreduced reactions of 5 or 6 mainly occur. In acetonitrile with sodium hydroxide, toluene, or xylene, photocyclization of 5, 6 occur exclusively. The triplet state is mainly involved in the photocyclization of 5 or 6, because of the inhibition of oxygen.

• The Korean Journal of Ecology
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• v.21 no.3
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• pp.263-268
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• 1998

The composition and concentration of monoterpenes in the leaves of Artemisia japonica were determined. And seasonal variation in monoterpenes of A. japonica were investigated. Samples were taken from five sites at Mt. Muhak. Monoterpenes in the leaves were analyzed using gas chromatography-mass spectrometry. The leaf monoterpene fractions were dominated by R.T. 5.026, ${\alpha}-thujene$, sabinene, ${\beta}-pinene$, cyclohexane (R.T.=12.859) and R.T. 23.149. There were marked seasonal differences in concentration and composition of leaf monoterpenes. There were many kinds of monoterpenes in leaf of spring time, however most of monoterpenes concentration was small. On the other hand, there were not many kinds of monoterpenes in late time, but monoterpene concentrations were increased.

• Journal of Life Science
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• v.9 no.6
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• pp.715-721
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• 1999

The biodegradative potentialities of a toluene-tolerant Pseudomonas sp. BCNU 154, isolated from waste water, were investigated. Among 16 aromatic substrates tested, cumene, cyclohexane, ethylbenzene, p-xylene, m-xyene, toluene and diphenylether were metabolized. Pseudomonas sp. BCNU 154 degraded aerobically toluene, ethylbenzene, p-xylene and cumene. With toluene competitive degradation occurred after 12 hours, but with p-xylene and cumene, and with ethylbenzene, 90 and 75% degradation occurred after 12 hours of incubation, respectively.

• Journal of the Korean Chemical Society
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• v.10 no.3
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• pp.136-142
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• 1966

The Transient State Theory of Significant Liquid Structure has been successfully extended to binary mixture, benzene-cyclohexane system, which gives positive deviation from Raoult's law. The partition function has been derived, and from it various thermodynamic properties, such as total and partial vapor pressures, molar volumes, and excess entropies have been calculated at the temperatures $303.15^{\circ},\;\313.15^{\circ},\;and\;343.15^{\circ}K$. The calculated values agree satisfactorily with the experimental data.