• Applied Chemistry for Engineering
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• v.20 no.3
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• pp.335-338
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• 2009

As important intermediates for blue emitting materials of organic light-emitting diodes, bromotriphenylethylene derivatives for distrylarylenes are prepared by reactions of bromobenzophenone with benzylphosphonates. The reaction produces a 60 : 40 mixture of (Z)- and (E)-geometric isomers that are difficult to be resolved. The (Z)-isomer is successfully isolated by a selective recrystallization process using 2-propanol as a solvent. The X-ray structure analysis of (Z)-isomer shows that dihedral angles between tert-butylphenyl ring and bromophenyl ring and between bromophenyl ring and phenyl ring are $56.5(4)^{\circ}$ and $74.1(4)^{\circ}$, respectively.

• Applied Biological Chemistry
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• v.26 no.4
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• pp.222-230
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• 1983

This study was designed to develop a process for the immobilization of xylose isomerase(D-xylose ketol isomerase, EC 5.3.1.5) from Streptomyces griseolus previously isolated by the authors and its application on a pilot plant scale for the production of high fructose corn syrup. The biomass which has endo-excreted xylose isomerase was homogenized under a pressure of $500kg/cm^2$ and 90.8% of the enzyme recovery of the native activity was obtained as compared to 54.7% recovery by the lysozyme treatment. Ionic bonding method was adopted for the enzyme immobilization due to its many reported merits. It was found that the porous resins such as Diaion HP 20, Duolite A-7, Amberlite IRA 93 and 94 were effective in immobilizing the enzyme. In addition, it was disclosed that the regeneration form of $BO_4--$ is effective for Amberlite IRA 93 and $HCO_3-$ for Diaion HP 20. Optimal immobilization condition for Amberlite IRA 93 was pH 8.0 and $55^{\circ}C$ yielding 80.6% of immobilization. Activity decay test showed half life of the immobilized enzyme with Amberlite IRA 93 was more than 24 days at $65^{\circ}C$. The carrier was evaluated to be resuable and its result showed the relative immobilization yields were 98.2, 93.3, 90.7 and 87.5%, respectively at second, third, forth and fifth rebinding test of the enzyme on Amberlite IRA 93. Optimal temperature of the immobilized enzyme was slightly lowered and the range widened to $60\sim70^{\circ}C$, while optimal pH moved toward $8.0\sim8.3$ in its isomerization reaction. The trial production result of high fructose corn syrup in pilot scale immobilization showed that one liter of immobilized xylose isomerase (350 IXIU/ml-R) is capable producing about 293l high fructose corn syrup(75% dry substance) in 30 days.

• Management & Information Systems Review
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• v.39 no.1
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• pp.75-91
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• 2020

The purpose of this study is to examine the application of in-depth interviews in terms of exploration on the basis of the theoretical basis of various aspects of consumer empathy, and the question of whether the consumer can expand to the process of self empathy. Most studies related to consumer empathy divide the responsive dimension of consumer empathy into rational and emotional dimension based on empathy theory, and look at the empathic response perceived by consumers to the stimulus presented from the current point of view. In this study, however, we want to go one step further and confirm that the consumers themselves can ultimately go to the self-empathy stage by forming a creative street of reproduction and redevelopment. As a result of exploratory research through in-depth interviews, it was indirectly confirmed that consumer's empathetic response to specific marketing stimulus exists at the level of creative and self-empathetic as well as the emphasis of previous studies. Based on these findings, this study confirmed that consumer empathetic responses could go beyond a single dimension to form a multidimensional structure and move toward an expanded structure of empathic self-creation. This suggests that consumers' empathic responses should be grasped in terms of continuity of empathic responses rather than explained in a specific dimension. Although this study is meaningful as an early research of exploratory nature, it is necessary to supplement various content validity and refine the research method through subsequent studies. This study is expected to expand the understanding that consumer's empathy can be extended to other people's empathy and to be self-empathy.

• Applied Chemistry for Engineering
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• v.8 no.2
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• pp.191-196
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• 1997

The isothermal reduction on $Pt/MoO_3/SiO_2$ at $50^{\circ}C$ demonstrates that the rate of hydrogen spillover is increased as calciantion temperature increases. That is due to the overlayer formation over the surface of Pt crystallites, investigated by TEM and CO chemisorption. It is known that reaction mechanism of skeletal isomerization of 1-butene into iso-butene is composed of 2 step such as formation of carbonium ion and isomerization of methyl group. It is expected that the increase of i-butene yield after calcination at $250^{\circ}C$ is due to increased rate of hydrogen spillover coming from first, overlayer formation over Pt surface and second, chlorine lessoning from $PtCl_x$ precursor.

• Proceedings of the KSRS Conference
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• 2006.03a
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• pp.283-286
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• 2006

인공위성 영상자료를 이용하는 원격탐사는 지질, 환경, 지형도제작 등 다양한 분야에서 연구되고 있다. 특히 다중 및 초분광영상자료는 태양을 에너지원으로 하여 지표면 전자기파의 반응을 영상화하는 다중 및 초분광영상자료의 활용을 위해 분광반사율정보가 더욱 활발하게 이용될 것으로 기대된다. 본 연구에서는 고창지역에 대해 주기적으로 실시하고 있는 분광반사율 및 USGS 분광라이브러리 성과를 이용하여 다중파장대 위성영상자료인 ASTER와 분광반사율을 이용한 위성영상의 활용가능성 및 검보정의 가능성을 제시 하고자 한다.

• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.393-398
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• 1991

An experimental reactor system was devised and employed to examine catalytic coal gasification. A 4-kw tungsten halogen lamp heater combinded with a graphite sample basket coated with silicon nitride film made rapid heating and cooling possible. Also a small graphite cap on the thermocouple tip which located just beneath the sample basket helped remarkably to read real temperatures. Silicon nitride film on the basket and the cap showed very good protection against the reaction between graphite and oxidant gases during the experiments. The weight of specimen could be continuously measured without disturbance.

• Journal of the Korean Chemical Society
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• v.31 no.5
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• pp.419-424
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• 1987

Kinetic studies on the solvolysis of para-methyl benzyl nitrate and benzyl nitrate were carried out in aqueous methanol, ethanol, acetonitrile, acetone, tetrahydrofuran and dioxane mixtures at 60$^{\circ}$C. The rates were faster in protic solvent mixtures than in aprotic solvent mixtures. This was considered in the light of transition state stabilization by hydrogen bonding solvation of protic solvent mixtures. Grunwald-Winstein equation, extended Grunwald-Winstein equation and correlation between E$_T$(30) and rate constant were applied in order to discuss the transition state variations caused by changing benzyl substituents and solvents. The results showed that strong electrophilic assistance of solvent is operative in the the water-rich solvents.

• Applied Chemistry for Engineering
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• v.5 no.4
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• pp.609-615
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• 1994

Partial oxidation of ethylene over 10wt% $Ag/{\alpha}-Al_2O_3$ catalyst was studied with a pulse reactor which was connected directly to a G. C. When ethylene was injected after oxygen injection at the temperature where molecular adsorption of oxygen is difficult ethylene oxide was evolved. From the results, it is suggested that adsorbed atomic oxygen is related with the evolution of ethylene oxide. The selectivity to ethylene oxide decreased with the decrease of the amounts of adsorbed oxygen and bulk oxygen. Ethylene oxide was either decomposed to ethylene and adsorbed oxygen or isomerized to acetaldehyde. However, the isomerization of ethylene oxide to acetaldehyde was strongly suppressed by the preadsorbed oxygen.

• Journal of the Korean Chemical Society
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• v.28 no.4
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• pp.210-216
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• 1984

Solvatochromic comparison methods were applied to determine Taft's solvent parameters, ${\pi}^{\ast}$(solvent polarity-polarizability), ${\alpha}$(solvent hydrogen bond donor acidity) and ${\beta}$ (solvent hydrogen bond acceptor basicity) for MeOH-MeCN solvent mixtures. Swain's solvent parameters A(anion solvation scale) and B(cation solvation scale) were also determined by least square fitting of kinetic data in the same binary solvent mixtures. It was found that: (i)${\beta}$ depends on the basicity of the solvent and increases with the MeOH content owing to the increase in polymeric structure of methanol; (ii) ${\pi}^{\ast}$depends on the dipole moment of the solvent and increases with the MeCN content of the solvent; (iii) ${\alpha}$ increases rapidly with the MeOH content as the hydrogen bond donor acidity of the solvent mixtures increases. Taft's reaction constants a and s and Swain's reaction constants a and b were determined for the reactions reported from our laboratory previously using solvent parameters determined in this work. No meaningful inter-relationship was found between the two set of reaction parameters, but a good linear correlation was found between the ratios a/s and a/b. Solvent effect on the reaction mechanism, substituent effect and leaving group ability were examined in the light of these reaction constants ratios.

• Journal of the Korean Chemical Society
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• v.32 no.6
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• pp.528-535
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• 1988

The rates of oxygen ring formation of $[Mo_2O_3(Ox)_2(OxH)_2(NCS)_2]$ have been investigated spectrophotometric method in binary aqueous mixtures. Temperature was $20^{\circ}C$ to $40^{\circ}C$ and pressure was varied up to 1500 bar. The observed rate constants are increased by hydrogen ion and decreased by thiocyanate. The more increasing of co-solvents dielectric constant, the more stable intermediate is formed. The observed rate constant is given by, $k_{obs}^{-1} = k^{-1} (1 + K^{-1}[H_2O]^{-1}) All activation parameters are positive values. The oxygen ring formation of [Mo_2O_3(Ox)_2(OxH)_2(NCS)_2]$ is believed to be a interchange-dissociative mechanism..