• Journal of the Korean Graphic Arts Communication Society
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• v.18 no.2
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• pp.125-132
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• 2000

To take an information of substitutent effect and thermodynamic of association at thiacarbocyanines, association constant $K_{D}$, free energy of association $\Delta$ $G_{D}$, enthalpies of association $\Delta$ $H_{D}$ were measured by spectrophotometer according to dependence on concentration of dyes and temperature of aqueous MeOH system. With increase of concentration dyes or decrease of temperature of aqueous MeOH system, absorption spectra of dyes exhibited equlilibria shift toward the dimer. Phenyl meso substituted thiacarbicyanine, DyeIII, resulted in higher $K_{D}$ and $\Delta$ $G_{D}$ values than DyeI and DyeII. To easily make an association of thacarbicyanine, meso substutituent group need to be a flat structure, which will make a park as well as lain tiles.tiles.ructure, which will make a park as well as lain tiles.les.

• Journal of the Korean Graphic Arts Communication Society
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• v.19 no.2
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• pp.22-29
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• 2001

To take an information of substitutent effect and thermodynamic of J-aggregate at thiacarbocyanines, association constant $K_{J}$ , free energy of association G$_{J}$ , enthalpies of J-aggregate H/suib J/ were measured by spectrophotometer according to dependence on concentration of dyes and temperature of aqueous MeOH and KCl salted-out system. With increase of concentration of dyes exhibited equilibria shift toward the aggregate. Phenyl meso substituted thiacarbycyanine, DyeIII, resulted in higher $K_{j}$ and G$_{J}$ values than DyeI and DyeII. To easily make J-aggregate of thiacarbocyanine, meso substutituene group need to be a flat structure, which will make a park as well as lain tiles.

• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.89-93
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• 2006

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.143-149
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• 1995

At low concentration a simplified model of organic dye-surfactant system has been used to evaluate. By applying the resultant three parameter equation to the experimental data, values for the equilibrium constants for the ion-pair formation $(K_O)$, surfactant molecule addition to aggregates $(K_S)$ and dye aggregation reactions $(K_D)$ could be calculated and changes of free energy have obtained from its values. $K_O$ and K_S$ values were larger than those expected electrostatic interaction indicatihng a hydrophobic contribution and the $K_D$ values were about 10~20 times higher than those found for association in pure aqueous solutions which can be ascribed to the screening effect of the electrostatic repulsion.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.519-533
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• 2010

Activity oefficients and solubilities of L-Alanine in aqueous solutions containing each of four electrolytes(NaCl, KCl, $NaNO_3$ and $KNO_3$) were measured at 298.15 K. The measurements of activity coefficients were carried out in the electrochemical cell coupled with two ion-selective electrodes(cation and anion), and the solubilities were measured by the gravimetric analysis of saturated solutions in equilibrium with the solid phase of L-alanine. To model the activity coefficients and solubilities of amino acid in the amino acid/electrolyte aqueous solutions, thermodynamic relations of the residual Helmholtz free energy in the amino acid/electrolyte aqueous solutions were developed based on the perturbed-chain statistical associating fluid theory(PC-SAFT) combined with the primitive mean spherical approximation(primitive-MSA). In the present model, it is assumed that the zwitterions of L-alanine are associated with each other and cross-associated with water molecules, and also cross-associated with the cation and anion dissociated from an electrolyte(inorganic salt). The activity coefficients and solubilities of L-Alanine calculated from the theoretical model proposed in this work are found to be well agreeable with experimental data.

• Journal of the Korean Chemical Society
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• v.24 no.6
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• pp.444-451
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• 1980

In order to further elucidate the process of electron solvation in liquids, the medium effect, as the difference between the free energy of $H^+$ in aqueous and non-aqueous states (${\Delta}{\Delta}G_0$), of THF-water mixtures has been investigated. (${\Delta}{\Delta}G_0$) were determined by electromotive force masurements of the cell Pt$H_2Q$, Q, HCI, THF, $H_2O$|KC1 | $Hg_2Cl_2$|Hg(Pt), where $H_2Q$ and Q are hydroquinone and quinone respectively. The effect of dielectric constant on the difference of free energy and the absorption energy of solvated electrons have been studied. For the consideration of these effect the polymerization of water in THF has been studied. Near infrared spectrum of O-H stetching energy has been used to measure the extent of water aggregates. The expermental results indicate that at least in some composition of binary mixtures the electrons or other ions are solvated preferentially with one component of solvents.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.3
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• pp.37-42
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• 2004

흡수식 냉동기의 구성요소에 관한 성능향상 및 배열을 이용한 코제네레이션 시스템의 소개한다. 1997년 12월에 개최된 지구온난화 방지 교토회의(COP3-기후변동협조조약 제3회 체결국 회합)에서, 일본은 2008년-2012년까지 온실효과가스의 배출량을 1990년도 시점을 기준으로 6% 삭감하기로 합의하였다. 이러한 배경에 따라 $CO_2$ 배출량의 삭감에 대한 새로운 공업기술의 전개가 진행되고 있으며, 일본의 냉동공조산업 분야에서도 코제네레이션이라는 에너지 절약 관점으로부터 흡수식 냉동기가 다시 주목을 받게 되는 계기가 되었다.(중략)

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.295-305
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• 2004

Colloid and surface chemistry have been focused on surface area and surface energy. Local surface properties such as surface density, interaction, molecular orientation and reactivity have been one of interesting subjects. Systems of such surface energy being important would be listed as association colloid, emulsion, particle dispersion, foam, and 2-D surface and film. Such nanoparticle systems would be applied to drug delivery systems and functional cosmetics with biocompatible and degradable materials, while nanoparticles having its size of several nm to micron, and wide surface area, have been accepted as a possible drug carrier because their preparation, characteristics and drug loading have been inves-tigated. The biocompatible carriers were also used for the solubilization of insoluble drugs, the enhancement of skin absorption, the block out of UV radiation, the chemical stabilization and controlled release. Nano/micro emulstion system is classified into nano/microsphere, nano/microcapsule, nano/microemulsion, polymeric micelle, liposome according to its prep-aration method and size. Specially, the preparation method and industrial applications have been introduced for polymeric micelles self-assembled in aqueous solution, nano/microapsules controlling the concentration and activity of high concen-tration and activity materials, and monolayer or multilayer liposomes carrying bioactive ingredients.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.655-660
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• 2013

In this review, I present the configuration behaviors of various Janus particles at fluid-fluid interfaces. As a model system, Janus spheres, Janus ellipsoids, and Janus dumbbells are selected to investigate the effect of shape, size, and wettability on their configurations. In particular cases, Janus ellipsoids can adopt two distinct configurations (i.e., upright and tilted configurations) due to the presence of two energy minima in the attachment energy profile. On the contrary, a single energy minimum is found in the case of Janus dumbbells such that they adopt either the upright or tilted configuration. Interestingly, the geometric and chemical asymmetry and anisotropy in the characteristic properties of Janus dumbbells lead to an intermediate state in which the particles can rotate freely in a certain range of orientation angles.

• Journal of the Korean Chemical Society
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• v.29 no.1
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• pp.38-44
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• 1985

Photoreaction path for the monocyanochromium (Ⅲ) ion was inferred from the experimentally observed product ratio and theoretical analysis. The angular overlap model was used to analyze the d-orbital of various intermediates along a selected reaction coordinate and to determine quartet state energy level. A loss of equatorial ammine leads to pentacoordinated square pyramid with CN- ligand in an equatorial position. The SP(CNeq) intermediate undergoes a rearrangement by the N-Cr-CN bending. This process leads to a trigonal bipyramidal intermediate in which the CN- ligand is located in equatorial position. The subsequent association with a solvent molecule should probably proceed by lateral attack an one edge of the equatorial triangle. The assumption adopted above was consistent with experimental results.