• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.527-533
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• 1991

Template condensation reactions of formaldehyde with appropriate tetramines and diamines in the presence of N(II) or Cu(II) ion produce square planar complexes of hexaaza macrotricyclic and macrotetracyclic ligands $[M(L)]^{2+}$(M = Ni(II) or Cu(II); L = 4-methyl-1,3,6,8,11,14-hexaazatricyclo[12,2,1,$1^{8,11}$]octadecane(C), 1,3,10,12,15,18-hexaazatetracyclo[16,2,1,$1^{12,15},0^{4,9}]$docosane(D) 4-methyl-1,3,6,8,12,15-hexaazatricyclo[13,3,1,$1^{8,12}$]eicosane(F), or 1,3,10,12,16,19-hexaazatetracyclo[l7,3,1,$1^{12,16},0^{4,9}]$tetracosane(G). These complexes contain two 1,3-diazacyclopentane or 1,3-diazacyclohexane rings in the six-membered chelate rings. The complexes of C and F contain one methyl group and those of D and G one cyclohexane ring in the five-membered chelate ring. Synthesis and characterization of the Ni(II) and Cu(II) complexes are presented. The effects of the ligand structure on the equilibrium $[Ni(L)]^{2+}2H_2O{\rightleftharpoons}[Ni(L)(H_2O)_2]^{2+}$ in aqueous solutions are described.

• Journal of the Korean Chemical Society
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• v.30 no.5
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• pp.483-487
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• 1986

The synthesis of $\beta-damascone$ (I), an odoriferous natural product, was investigated from 2,2,6-trimethylcyclohexanone (II); (II) was ethynylated by the action of monoacetylide anion prepared from acetylene and sec-butyllithium at -78${\circ}C$, to give an ethynylcarbinol(III), which was isomerized to an acetylcyclohexene(IV) by refluxing in aqueous oxalic or formic acid. (IV) was treated with sec-butyllithium, the enolate was reacted with freshly dried acetaldehyde, and the resultant $\beta-hydroxyketone$ (V) was dehydrated by TsOH to ${\beta}$-damascone, trans-2,6,6-trimethyl-1-crotonyl-1-cyclohexene(I).

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.5
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• pp.1-9
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• 2011

Researches on hypersonic aircraft technologies have been carried out to increase flight speeds. However, increase in flight speeds causes heat loads that could lead structural change of aircraft's component. Researches on cooling technologies using endothermic fuels are progressing in the USA, France and Russia to treat the heat loads. Endothermic fuels are liquid hydrocarbon aircraft fuels which are able to absorb the heat loads by undergoing endothermic reactions, such as thermal and catalytic cracking. In this study, methylcyclohexane, n-octane, and n-dodecane were selected as model endothermic fuels and experiments in endothermic properties were implemented. Experimental conditions were supercritical condition of each model fuels in which actual endothermic fuels were exposed. The object of this study is to identify endothermic properties of the model endothermic fuels and to predict endothermic properties of actual fuels such as kerosene fuels.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.279-286
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• 2010

Hypersonic aircraft technologies have been developed with increase in flight speeds. As hypersonic flight speeds increase, heat loads on an aircraft and it's engine increase. Researches on cooling technologies using endothermic fuels are progressing in the USA, France, and Russia to treat the heat loads. Endothermic fuels are liquid hydrocarbon aircraft fuels which are able to absorb the heat loads by undergoing endothermic reactions, such as thermal and catalytic cracking. In this study, methylcyclohexane, n-octane, and n-dodecane were selected as model endothermic fuels and experiments in endothermic properties were implemented. Experimental conditions were supercritical phase of each model fuels in which actual endothermic fuels were exposed. The object of this study is to identify endothermic properties of the model endothermic fuels and to predict endothermic properties of actual fuels such as kerosene fuels.

• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.87-94
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• 1992

The elution behavior of polystyrenes(PS), polymethylmethacrylates (PMMA), polybutadienes(PB), PS-PMMA(SM) block copolymers and PS-PB star shaped copolymers on the cross-linked polystyrene gels was studied. An interpretation was proposed for the plots of log hydrodynamic volume versus retention volume of solutes in the mobile phases such as tetrahydrofuran, toluene, chloroform, methylene chloride and tetrahydrofuran-cyclohexane mixture. In order to predict the retention of solutes from their physical properties, multiple stepwise regression analysis was applied to obtain the correlation. The distribution coefficients($K_p$) of solute-gel interactions in GPC for homopolymers and PS copolymers were also obtained in terms of network-limited separation mechanism. In the cases of PS and PB, $K_p$ values approach unity, while $K_p$ values for PMMA decrease as MW increase in the good solvent, but in poor solvent, $K_p$ values increase as MW increase. $K_p$ values of PS copolymers are dependent on their MW and composition, therefore, morohology of SM block copolymer is predicted to be random phase. A single universal plot of log[η]M vs. $(V_r-V_o)/K_p$