• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.195-195
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• 2011

공기 중 산소를 이용한 다양한 산화반응에 적합한 이종상 촉매 개발이 공업적으로나, 학문적으로 중요한 의미를 갖는다. 우리는 수산화 인회석(hydroxyapatite, HAP)에 Cu이 도입된 새로운 이종상 촉매를 합성하였으며, 이를 이용하여 Mesitylene의 산화반응을 통해 반응성을 관찰하였다. 전이금속 Cu를 이온교환 반응 하는 과정에서 온도와 압력조건의 변화가 촉매의 활성에 미치는 영향에 대해 연구하였다. 반응 후의 생성물질은 GC/MS를 통해 알아내고 Mesitylene 이외에 벤젠고리에 치환된 알킬기의 수가 다른 물질의 산화반응을 수행하였다.

• Journal of the Korean Chemical Society
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• v.42 no.2
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• pp.209-213
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• 1998

The higher order structure of Pseudomonas alcaligenes 5S rRNA has been investigated by using ($\eta^{6}$-mesitylene) manganese (Ⅰ) tricarbonyl hexafluorophosphate[MTH-Mn (Ⅰ)], dimethylpyrocarbonate, potassium permanganate as chemical probes. The sequences cleaved strongly by MTH-Mn (Ⅰ) on the tertiary structure of the 5S rRNA are $G_{12}AUGG_{16}$ of loop a, $G_{51}AAGUGAAGC_{60}$ of the region b-C, $U_{65}-AGCG_{69}$. of the region B-a, and $G_{72}AUGG_{76}$ of loop d. Based on such cleavage patterns of 5S rRNA by MTH-Mn(Ⅰ) and other chemical probes, we presume that the sequences strongly cleaved form pocket-like structure as in the the corner of L structure of $tRNA^{Phe}$. We also presume that the region b-C and loop d together play a role of hinge in forming the pocket-like structure in the 5S rRNA.

• Rapid Communication in Photoscience
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• v.4 no.2
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• pp.31-33
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• 2015

Fluorescence (FL) properties of a novel donor-acceptor dyad, comprised of mesitylene and 1,4-dicyano-2-methylnaphthalene (DCMN) subunits connected by an ether linkage, were elucidated. The dyad in cyclohexane exhibits FL arising from an intramolecular exciplex. In the crystalline state, the dyad does not emit light from intra- and inter-molecular exciplexes but rather displays FL that is nearly equivalent to that of 2-methoxymethyl-substituted DCMN. However, the emission spectrum of the crystalline dyad contains a shoulder in the long wavelength region, suggesting that weak intercolumnar charge-transfer interactions take place between columns consisting of the mesitylene and DCMN subunits.

• Journal of the Korean Chemical Society
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• v.25 no.2
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• pp.75-84
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• 1981

Ultraviolet spectrophotometric investigations have been carried out on the systems of mesitylene with iodine, bromine, iodine monochloride and iodine monobromide in carbon tetrachloride. The results reveal the formation of the charge transfer complexes of the type, $C_6H_3(CH_3)_3{\cdot}X_2$ or $C_6H_3(CH_3)_3{\cdot}IX$ (X denotes halogen atoms). The equilibrium constants were obtained in consideration of that absorption maxima due to the formation of the charge transfer complexes shift to blue with the increasing temperatures. Thermodynamic parameters, ${\Delta}H$, ${\Delta}G$ and ${\Delta}S$ for the formation of the charge transfer complexes were calculated from these values. These results indicate that the relative stabilities of the mesitylene complexes at each temperature decrease in the order, ICl > IBr > $I_2$ > $Br_2$. This order may be a measure of their relative acidities toward mesitylene, which is explaned in terms of the relative polarizabilities of halogen molecules and the relative electronegativities of halogen atoms. These results combined with previous study of this series indicated that the relative stabilities of the polymethylbenzene complexes with iodine increase in the order Benzene < Toluene < Xylene < Mesitylene Thus, analysis of these findings is discussed.

• Bulletin of the Korean Chemical Society
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• v.17 no.10
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• pp.951-953
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• 1996

• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.417-421
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• 2008

The efficient synthesis of four mesitylene-based receptors 1-4 and their potentiometric response characteristics to alkali metal, alkaline earth metal, and transition metal ions, under various pH conditions are outlined. Receptor 1-based electrode exhibited more sensitive response to Ag+ ion (49 mV/decade of range from 10-6 to 10-2 M) than the 2-based electrode (47 mV/decade of range from 3 ´ 10-5 to 10-2 M), while the 3- and 4-based ones revealed sub-Nernstian below 40 mV/pAg+. All electrodes showed substantial responses to Ag+ ion under acidic condition, but there was almost nil-response to other transition metal ions (Fe2+, Co2+, Zn2+, Ni2+, Pb2+, Cd2+, Cu2+ and Hg2+). The association constant of receptor 1 toward Ag+ ion, measured by 1H NMR titration, showed the largest value (200 M-1) among the tested receptors. The results were interpreted with semi empirically-modeled structures.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.200-200
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• 2011

Hierarchical mesoporous ZSM-5 with enhanced mesoporosity was synthesized by microwave through the rapid assembly via ionic interaction between sulfonic acid functionalized ZSM-5 nano particles and cationic surfactant. The catalytic performance of enhanced accessibility due to mesoporosity and acidity were investigated in the alkylation of mesitylene with benzyl alcohol as alkylating agent. The effect of mole ratio of aromatic with benzyl alcohol, reaction time and alkylation agent were also studied. The enhanced mesoporosity and acidity of sulfonic acid functionalized mesoporous ZSM-5 induced activity enhancement compared with non-functionalized mesoporous ZSM-5, sulfonic functionalized mesoporous ZSM-5 synthesized by hydrothermal method and conventional microporous ZSM-5. The sulfonic acid functionalized mesoporous ZSM-5 showed much higher chemoselectivity of benzylated mesitylene than others, whereas the others mainly show dibenzyl ether as product. This significant difference in catalytic selectivity was resulted from the existence of mesopores, which definitely allowed the benzylation in mesopores.

• Journal of Life Science
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• v.24 no.1
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• pp.81-85
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• 2014

Pseudomonas sp. BCNU 106 isolated from industrial wastewater was able to produce indigo from indole by utilizing various organic solvents. BCNU 106 produced indigo effectively when grown in the presence of a large volume of p-xylene, propylbenzene, and mesitylene and a high level of indole. The present study demonstrated that the maximal yield was achieved with 20% (v/w) p-xylene and 4 g/l indole. Under these conditions, the indigo yield and the transformation efficiency of indole were 315.5 mg/l and 97%, respectively. The results suggest that Pseudomonas sp. BCNU 106 might be a potential candidate for industrially important indigo production.

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.405-412
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• 1980

The effect of pressures and temperatures on the stabilities of the mesitylene-iodine charge transfer complex have been investigated through ultraviolet spectrophotometric measurements in n-hexane. The stabilities of complexes were measured at 25, 40 and $60^{\circ}C$ under 1∼1600 bars. The equilibrium constant of the complex was increased with pressure and decreased with temperature raising. The absorption coefficient was increased with both pressure and temperature. Changes of volume, enthalpy, free energy and entropy for the formation of complexes were obtained from the equilibrium constants. The red-shift observed a higher pressure, the blue-shift at a higher temperature and the relation between pressure and oscillator strength were discussed by means of thermodynamic functions.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.100-106
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• 1992

The fluorescence characteristics of copolymers of styrene-maleic anhydride(PSMAn), styrene-maleic acid (PSMA), and PSMA complexed with $Eu^{3+}$ (PSMA-Eu) in tetrahydrofuran were studied. The excimer of PSMA and PSMA-Eu with 75% mole fraction of styrene appears to have larger binding energy than that with 50% or 67% styrene. The ratio of excimer to monomer intensities showed little change with the increase of styrene concentration up to $8.0{\times}10^{-3}M$, indicating the excimer formation is due to intramolecular process. Three existing mechanisms for intramolecular excimer formation are considered inadequate to explain the observed behavior. The quenching of excimer intensity by benzyl-acetate, mesitylene, and $CCl_4$ is interpreted in terms of the molar volume of quencher.