• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.257-258
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• 2003

사회가 고도로 발달하면서 현대인의 생활공간은 대부분 사무실이나 가정에서 보내는 시간이 하루의 80-90% 이상을 차지하므로 오히려 실외공기보다 실내환경의 공기오염이 수백 배 높은 실정이다1). 대부분의 시간을 특정공간에서 보내게 되므로 현대인의 건강과 편리함을 위해 실내공간에 설치되는 탈취제품(공기 청정기)이 많이 상품화 되고 있다. 본 연구에서는 암모니아(NH$_3$), 트리메틸아민(($CH_3$)$_3$N), 초산($CH_3$COOH), 황화수소(H$_2$S), 메칠멀켑탄($CH_3$SH), 황화메틸 ($CH_3$S$CH_3$), 이황화메틸($CH_3$SS$CH_3$), 아세트알데히드($CH_3$CHO), styrene(C$_{8}$H$_{8}$)등 9종의 악취물질을 대상으로 탈취제품의 객관적인 탈취 능력 평가를 위한 시험방법을 개발하고자 하였다.(중략)

• Nuclear Engineering and Technology
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• v.9 no.1
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• pp.33-38
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• 1977

The molecular orbital theory (EHT) has been applied to the discussion of the reaction mechanism and reactivity of p-substituted phenyl-$\beta$-chloroethyl-sulfones, R-(equation omitted)-$SO_2CH_2CH_2Cl$, where R are $CH_3O\;,CH_3$, Cl, H. The theoretical conclusion derived are in good agreements with the experimental order.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2517-2522
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• 2012

New polynuclear poly(hexaaza macrocyclic) copper(II) complexes $[1](ClO_4)_{2n}{\cdot}(H_2O)_{2n}$, $[2](ClO_4)_{2n}{\cdot}(H_2O)_{2n}$, and $[3](ClO_4)_{2n}{\cdot}(H_2O)_{2n}$ have been prepared by the one-pot reaction of formaldehyde with ethylenediamine and 1,2-bis(2-aminoethoxy)ethane, 1,3-diaminopropane, or 1,6-diaminohexane in the presence of the metal ion. The polymer complexes contain fully saturated 14-membered hexaaza macrocyclic units (1,3,6,8,10,13-hexaazacyclotetradecane) that are linked by $N-(CH_2)_2-O-(CH_2)_2-O-(CH_2)_2-N$, $N-(CH_2)_3-N$, or $N-(CH_2)_6-N$ chains. The mononuclear complex $[Cu(H_2L^5)](ClO_4)_4$ ($H_2L^5$ = a protonated form of $L^5$) bearing two $N-(CH_2)_2-O-(CH_2)_2-O-(CH_2)_2-NH_2$ pendant arms has also been prepared by the metal-directed reaction of ethylenediamine, 1,2-bis(2-aminoethoxy)ethane, and formaldehyde. The polymer complexes were characterized employing elemental analyses, FT-IR and electronic absorption spectra, molar conductance, X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron micrograph (SEM). Electronic absorption spectra of the complexes show that each macrocyclic unit of them has square-planar coordination geometry with a 5-6-5-6 chelate ring sequence. The polymer complexes as well as $[Cu(H_2L^5)]^{4+}$ are quite stable even in concentrated $HClO_4$ solutions. Synthesis and characterization of the polynuclear and mononuclear copper(II) complexes are reported.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1681-1686
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• 2014

A series of hybrid molecules between (${\alpha}$)-lipoic acid (ALA) and 4-amino-1-benzyl piperidines were synthesized and their in vitro cholinesterase (acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)) inhibitory activities were evaluated. Even though the parent compounds did not exhibit any inhibitory activity against cholinesterase (ChE) with the exception of compound 14 ($IC_{50}=255.26{\pm}4.41$ against BuChE), all hybrid molecules demonstrated BuChE inhibitory activity. Some hybrid compounds also displayed AChE inhibitory activity. Specifically, compound 17 was shown to be an effective inhibitor against both AChE ($IC_{50}=1.75{\pm}0.30{\mu}M$) and BuChE ($IC_{50}=5.61{\pm}1.25{\mu}M$) comparable to galantamine ($IC_{50}=1.7{\pm}0.9{\mu}M$ against AChE and $IC_{50}=9.4{\pm}2.5{\mu}M$ against BuChE). Inhibition kinetic studies using compound 17 indicated a mixed inhibition type for AChE and a noncompetitive inhibition type for BuChE. Its binding affinity ($K_i$) values to AChE and BuChE were $3.8{\pm}0.005{\mu}M$ and $7.0{\pm}0.04{\mu}M$, respectively.

• Bulletin of the Korean Chemical Society
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• v.5 no.1
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• pp.3-16
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• 1984

The effect of solvent on the dipole moments for (chloromethyl) stannanes has been investigated by applying EHT calculation for the isomers of trigonal bipyramidal Sn(Ⅳ)$Cl_4X$ and $Cl_n$Sn(Ⅳ) $(CH_2Cl)_{4-n}$, octahedral Sn(Ⅳ)$Cl_42X$ and $Cl_nSn$(Ⅳ)$(CH_2Cl)_{4-n}$ 2X type complexes in dioxane and ethylacetate solutions (X: dioxane or ethylacetate). For Sn(Ⅳ)$Cl_4$ in dioxane solution, the calculated dipole moment for the trigonal bipyramidal Sn(Ⅳ)$Cl_4X$ type complex [isomer (b)] is closer to the experimental dipole moment than octahedral Sn(Ⅳ)$Cl_4X$2X type complexes. This calculated dipole moment suggests that Sn(Ⅳ)$Cl_4X$ may have the trigonal bipyramidal structure in dioxane solution. However, the calculated dipole moment for octahedral $Cl_3$Sn(Ⅳ) ($CH_2$Cl)2X type complex [Isomer (d)], ClSn(Ⅳ)(CH2Cl)32X type complex [Isomer(k)] and Cl2Sn(Ⅳ)(CH2Cl)22X type complex [Isomer(h)] are closer to the experimental dipole moments than other isomers for octahedral complexes and trigonal bipyramidal complexes. Such theoretical results indicate that $Cl_3Sn$(Ⅳ )($CH_2Cl$), ClSn(Ⅳ)$(CH_2Cl)_3$ and $Cl2Sn$(Ⅳ)$(CH_2Cl)_2$ complexes may have octahedral structures, Isomer(d), (k) and (h) in ethylacetate solution, respectively.

• Journal of the Semiconductor & Display Technology
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• v.7 no.3
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• pp.1-4
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• 2008

The chemical shift of SiOC film was observed according to the flow rate ratio. SiOC film had the broad main band of $880\sim1190cm^{-1}$ and the sharp Si-$CH_3$ bond at $1252cm^{-1}$, and the peak position of the main bond in the infrared spectra moved to high frequency according to the increasing of an BTMSM flow rate. So the increment of the alkyl group induced the C-H bond condensation in the film, and shows the blueshift in the infrared spectra. In the case of P5000 system of Applied Materials Corporation, the strong bond of Si-CH3 bond in precursor does not enough to dissociated and ionized, because low plasma energy due to the capactive coupled CVD. Therefore, there was the sharp peak of Si-$CH_3$ bond at $1252cm^{-1}$.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.296-300
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• 1997

The intracluster ion/molecule reactions within 1,1-difluoroethene homocluster have been studied by electron-impact quadrupole mass spectrometry. When CH2CF2 seeded in helium is expanded and ionized by electron impact, two different types of ion/molecule association (polymerization) reaction products, i.e., (CH2CF2)n+ (n≥l) and (CF2CH2)qX+ (X=fragment species, q≤n), are formed. The higher association products, (CH2CF2)n+ (n=3, 4), have shown stronger intensities over the lower association product, (CH2CF2)2+, in the low electron impact energy region ( < 39 eV). These stronger intensities are interpreted in terms of the stabilization of these ions due to the ring formations over the dimer ion in this energy region. The evidence of ring formation mechanism is on the basis of the intensity distribution of fragments at various electron impact energy. In another typical branched-chain growth reaction of these compounds, the F-shift reaction path is found to be more favorable energetically than the H-shift via the fragment patterns of clusters and semi-empirical calculation.

• Bulletin of the Korean Chemical Society
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• v.18 no.3
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• pp.311-316
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• 1997

The synthesis and characterization of the mononuclear group 13 heterocyclic carboxaldehyde methyldithiocarbazate complexes Me2M[NC5H4CRNNC(S)SCH3] (M=Al, R=H(1); M=Ga, R=H(2); M=Al, R=CH3(3); M-Ga, R=CH3(4); M=In, R=CH3(5)) are described. Compounds 1-5 were prepared by the reaction of MMe3 (M=Al, Ga, In) with 2-formy or 2-acetylpyridine-S-methyldithiocarbazate in toluene. These compounds 1-5 have been characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and single-crystal X-ray diffraction. X-ray single-crystal diffraction analyses reveal that 4-5 are mononuclear metal compounds with coordination number of 5 and N,N,S coordination mode.

• Journal of the Korean Society of Combustion
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• v.15 no.4
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• pp.9-14
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• 2010

Numerical simulations of freely propagating fuel-rich $CH_4/CH_3Cl$ premixed flames were performed at atmospheric pressure in order to understand the effect of the oxygen enrichment on the production of PAH. A chemical kinetic mechanism was used, which involved 157 gas-phase species and 1693 forward reactions. The calculated flame speeds were compared with the experiments for the flames established on the equivalence ratios of 1~1.6, the results of which were in good agreement. As the level of oxygen enrichment was increased, the concentrations of one or four ring aromatic hydrocarbons were decreased. This might cause the fact that the contribution of PAH species to soot was weakened.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.218-223
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• 1995

A simple and efficient synthesis of new kind of Morindaparvin A derivatives (2~8) containing $-N(CH_3)_2,\;-OMe,\;-NH_2,\;-COOH,\;-CHClC(O)NH_2,\;-CHClCH_2OH\;and\;-CHClC(O)CH_3$ was completed with the reported 1,2-dihydroxyanthraquinone derivatives (9, 10).