• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.2
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• pp.157-162
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• 2000

The electro-optical characteristics of TN(twisted nematic)-LCD(liquid crystal display) with photo-dimerized on a PMCh(poly(4'methacryoyloxylchalcone)) surface using a new photo-dimerization method was studied. The excellent voltage-transmittance(V-T) curve of TN-LCD with photo-dimerized on a PNCh surface for 1 min. using a new photo-dimerization method was observed. Also, the voltage-hold-ing-ratio(VHR) of TN-LCD with photo-dimerized on a PMCh surface using a new photo-dimerization method is higher than that of conventional photo-dimerization method. Consequently, we suggest that the new photo-dimerization method. Consequently, we suggest that the new photo-dimerization method for LC aligning is the most promising rubbing-free techniques.

• Textile Coloration and Finishing
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• v.27 no.1
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• pp.1-10
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• 2015

The aim of the current study is to identify the dimerization and decomposition kinetics of the F-$D_M$ type. The regeneration of F-VS from $F_iF_j-D_M$ or the reversibility of the dimerizations were investigated. The order of real rate constants of the dimerization('$K_D{^{ij}}$) would seem to be similar to that of rate constants of a dimerization($K_D{^{ij}}$) for VS dyes at a given pH because of the constancy of the equilibrium constants($K_a{^j}$-value). The reverse reactions of the $D_M$ types are appeared to occur in two steps, the deprotonation of ${\alpha}$-carbon of the $D_M$ types and disproportionation. The ratio of the decomposition of the $D_M$ type to F-Hy and F-VS appears to be related with the ratio of $K_i/K_j$. Similarities were also found among various other reactions, including homo- and mixed dimerization. VS dyes undergoing fast hydrolysis have difficulty in forming a dimer. The higher the reactivity with cellulose or hydroxide ion, the smaller the dimerization. The easiness of the dimerization was thus found to be inversely proportional to the rate of hydrolysis.

• Journal of Life Science
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• v.13 no.3
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• pp.248-251
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• 2003

The kinetics of dimerization of a newly synthesized thyroglobulin (Tg), the precursor protein in the manufacture of thyroid hormone, was investigated in the endoplasmic reticulum of thyrocytes FRTL-5 cell line. The folded monomeric Tg was first detectable in a conformationally unstable form, from the examination of lysates of pulse labeled cultured thyrocytes by denaturing and nondenaturing gel electrophoresis by 15 min after biosynthesis. The first dimeric Tg was formed by 30 min after; the monomer declined and the dimer progressively increased, and 40 min after remarkable dimeric Tg form was found. Finally, dimerization was complete at 60 min after.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.715-719
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• 2000

A ceramic powder of destructive adsorbent was synthesized by impregnating copper and manganese on the surface of silica aerosil@. In-site FTIR measurements on pulses of malodorant tert-butylmercaptan injected over the powder showed that rert-butylmercaptan dimerized into di-tert-hutyldisulfide on the surface of the adsorbent in an ambient condition. GC/MS measurement on the gas over the adsorbent showed no tert-butylmercaptan remaining, and showed only the dimerization product of di-tert-butyldisulfide. Most of the dimerization product, di-tert-butyldisulfide,remained on the surface of the adsorbent as physisorbed condense, and apparently Iowered the destruction efficiency by blocking the surface from the access by tert-butylmercaptan. Upon being heated above $100^{\circ}C$ it was observed that the physisorbed di-tert-butyldisulfide dissociated back into tert-butylmercaptan. tert-butylmercaptan physisorbed on the activated carbon, thereby no dimerization was occurring on the surface of the activated carbon. In an argn environment, the dimerization reaction was practically not occurring even on the surface of the adsorbent, indicating the free oxygen in air was also participating in the dimerization reaction. Water was identified as a by-product of the dimerization reaction. Possible reactions on the surface of the adsorbent were proposed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.190-193
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• 2007

Present study examines the experimental results of polycyclic hydrocarbons compound prepared by norbornadiene dimerization reaction. Pentacyclic exo-t-exo, hexacyclic exo-endo, hexacyclic endo-endo isomers of NBD dimer were synthesized by selective dimerization of NBD monomer. Dimerization catalysts, reaction procedure and product analysis method were developed respectively. Through this experiment, mild reaction conditions, relatively high NBD dimer yields were obtained and this reaction technologies will be usefully applied to high energy density liquid fuel development.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.271-271
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• 2010

Using ab initio density functional theory, we investigate the dimerization and one-dimensional (1-D) polymerization of metal-encapsulated gold nanoclusters, M@$Au_{12}$ (M=W, Mo) and their structural and electronic properties. M@$Au_{12}$ clusters with a magic number 13 can form icosahedral and cuboctahedral structures. We consider various dimer configurations with different compounds and symmetries to find the most stable dimer structure in each case. Au atoms in the one cluster, which participate directly in dimerization, tend to form triangular bonds together with counterpart Au atoms in the other. It is found that both M@$Au_{12}$ and M@$Au_{12}$ clusters are stabilized by about 3 eV due to dimerization. We also calculate and compare the electronic and magnetic properties of different dimerized clusters. Based on our investigation on dimerization, we further study on 1-D polymerization of M@$Au_{12}$ with different compounds and symmetries. We will also discuss their formation energies as well as their electronic and magnetic properties.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2446-2450
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• 2013

Oxindole dimers have been used as intermediates in the synthesis of various cyclotryptamine alkaloids. An efficient direct synthesis of oxindole dimers has been carried out from 3-substituted oxindoles via an oxidative dimerization using manganese(III) acetate or copper acetate/silver acetate system.

• Bulletin of the Korean Chemical Society
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• v.3 no.3
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• pp.115-119
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• 1982

The photoreaction of maleimide, one of the best model compounds of DNA molecules for psoralen-DNA photoreactions, is studied in order to investigate the photoreactivity and the mechanism of the maleimide-psoralen photoreaction. The (2+2) photocyclodimer of maleimide was obtained in solution state by direct or sensitized irradiation. The rate constant of dimerization is determined by quenching studies and found to be of the order of $10^9 M^{-1}sec^{-1}$. The direct dimerization of maleimide is found to undergo through the triplet excited state. The quantum yields of dimerization are dependent on the maleimide concentration.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1763-1770
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• 2007

Strong solid acid catalysts, NiO/Al2O3-TiO2/WO3 for ethylene dimerization were prepared by the addition of Al2O3 and the modification with WO3. The acid sites and acid strength were increased by the inductive effect of WO3 species bonded to the surface of catalysts. The larger the dispersed WO3 amount, the higher both the acidity and catalytic activity for ethylene dimerization. The addition of Al2O3 to TiO2 up to 5 mol% enhanced acidity and catalytic activity gradually due to the interaction between Al2O3 and TiO2 and consequent formation of Al-O-Ti bond.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.53-58
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• 2006

A powder of destructive adsorbent was prepared by impregnating Mn and Cu on the surface of amorphous aluminosilicate. It catalytically dimerized tert-butyl mercaptan into di-tert-butyl disulfide on its surface. Turnover of the dimerization was strongly dependent on the surface morphology of the adsorbent, which could be altered by modification of aluminosilicate support. During the process of impregnation, which involved heat treatment at 500 ${^{\circ}C}$, the shape of the pore was preserved, though large fraction of micropores were eliminated. The reactive sites on the surface were poisoned as dimerization products strongly adhered on them. Therefore, high surface area was not always desirable. When the surface was heavily populated with “inkbottled” pores with a narrow entrance in uniform size, heavy poisoning of the reactive sites turned the destructive adsorbents almost useless.