• Rapid Communication in Photoscience
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• v.1 no.1
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• pp.19-20
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• 2012

Novel star-shaped imide compounds containing electron-donating triphenylamine and/or electron-withdrawing bis(trifluoromethyl)phenyl side groups were synthesized via a two-step process. First, 3,6-dibromo-benzene-1,2,4,5-tetracarboxylic acid (2B4BA) was reacted with 4-aminophenyl (diphenylamine) (ATPA) or 3,5-bis(trifluoromethyl)aniline (6FA) by imide reaction. Then, Suzuki coupling reaction was carried out on these compounds with 4-(N,N-diphenylamino)-1-phenyl boronic acid (BTPA) or 3,5-bis(trifluoromethyl)phenyl boronic acid (6FBB), resulting in 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[4-(diphenylamino) phenyl]-pyromellitimide (TPTPPI), 3,6-bis[3,5-bis(trifluoro methyl) phenyl]-N,N'-bis[3,5-bis(trifluoromethyl) phenyl]-pyro mellitimide (6F6FPI) or 3,6-bis[4-(diphenylamino)phenyl]-N,N'-bis[3,5-bistrifluoromethyl)phenyl]-pyromellitimide (6FTPPI). The imide compounds obtained were characterized by NMR, FT-IR, DSC, TGA, melting point analyzer, EA, and solubility measurements. In addition, their optical and electrical properties were evaluated by fluorescence spectroscopy, UV-vis spectroscopy, and cyclic voltammetry (CV). 6F6FPI exhibited deep blue emission (443 nm), along with high $T_m$ ($382^{\circ}C$) and relatively high $T_g$ ($148^{\circ}C$).

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.594-598
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• 2005

Treatment of a solution of $CuCl_2$ in dimethyl phosphate (DMP) with DMSO under nitrogen atmosphere afforded to a light blue fluorescence powder. Slow evaporation of $H_2O$-DMSO solution of this powder resulted in blue-sky crystals of a new polymeric Cu(II) complex, with a unit cell composed of $Cu_2(DMP)_4$(DMSO), (1). The crystal and molecular structure of the complex acquired crystallographically. Compound (1) crystallizes in the monoclinic space group $P2_1$/n with a = 12.8920(11) $\AA$, b = 13.1966(11) $\AA$, c = 14.7926(13) $\AA$, $\alpha$ = 90$^{\circ}$, $\beta$ = 98.943(2)$^{\circ}$, $\gamma$ = 90$^{\circ}$, V= 2486.1(4) ${\AA}^3$, and Z = 4. A square pyramidal environment for the metal center was established by coordination of oxygen atoms of four bridging DMP ligands in the basal positions and binding a tri-centered oxygen atom of DMSO in the apical disposition of Cu(II). The sixth position was also affected by a weak interaction with the sulfur atom of another DMSO. The phosphorous atom in the bridging DMP was arranged in a deformed tetrahedron with (gg) conformation for methyl esters with $C_{2v}$ symmetry.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.2
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• pp.91-95
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• 2017

We were designed the hole transport layer of the new composite skeleton structure having a high charge mobility and thermal stability. In this paper, a hole transport layer material based on thiophene molecular structure capable of hole mobility characteristics and high triplet energy was designed and synthesized. The structures and properties of the synthesized compounds were characterized by NMR, fluorescence spectroscopy and energy band gap. As a result of NMR measurement, it was confirmed that when analyzing the integrated type with the position where the measured peak is displayed, it agrees with the structure of hole transport materials. The emission characteristics of the hole transport layer material showed absorption characteristics at 412 nm and 426 nm, respectively, and exhibited emission characteristics in the range of 469 nm and 516 nm.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.5
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• pp.188-192
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• 2015

Gemological and spectroscopic properties of HPHT synthetic diamonds from New Diamond Technology (NDT) company in St. Petersburg (Russia) were examined. Their color (colorless, near-colorless with some boron and Fancy blue with high boron content) and clarity ($VVS-SI_1$) grades were comparable to those of top natural diamonds. NDT synthetic diamonds fluoresced and phosphoresced blue or orange under SWUV light. Photoluminescence spectra revealed H3 center with very small intensity and NV centers. The intensity of H3 in NDT synthetic diamond has very weak in comparison with natural one. Using a combination of gemological and spectroscopic tests, gem-quality synthetic diamonds from NDT can be distinguished from natural diamonds of similar quality.

• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.465-471
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• 2010

We assessed whether the cow1 mutant defects are associated with growth of Tos17 and T-DNA insertional rice in blue light (BL). Growth of oscow1 mutants which encoded a member of the YUCCA protein family was retarded in BL. Root to shoot ratios of the mutants were reduced about 2 times lower in the absence of NAA and about 2.5 times lower in the presence of NAA; the shoot growth was not significantly changed by NAA addition. Photosynthetic activity of the mutants was however inhibited in high light. Pigment analysis showed significant difference between wild-type (Chl a:b = 3.02) and mutants (3.84). Carotenoid contents of the mutants were also decreased considerably, implying the involvement of cow1 in pigment formation. These findings lead us to suggest that the growth retardation of oscow1 mutant plants by BL results from the difference of photosynthetic activity in part.

• BMB Reports
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• v.40 no.4
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• pp.453-458
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• 2007

Bacterial luciferase is a heterodimeric enzyme, which catalyzes the light emission reaction, utilizing reduced FMN (FMNH2), a long chain aliphatic aldehyde and $O_2$, to produce green-blue light. This enzyme can be readily classed as slow or fast decay based on their rate of luminescence decay in a single turnover. Mutation of Glu175 in $\alpha$ subunit to Gly converted slow decay Xenorhabdus Luminescence luciferase to fast decay one. The following studies revealed that changing the luciferase flexibility and lake of Glu-flavin interactions are responsible for the unusual kinetic properties of mutant enzyme. Optical and thermodynamics studies have caused a decrease in free energy and anisotropy of mutant enzyme. Moreover, the role of Glu175 in transition state of folding pathway by use of stopped-flow fluorescence technique has been studied which suggesting that Glu175 is not involved in transition state of folding and appears as surface residue of the nucleus or as a member of one of a few alternative folding nuclei. These results suggest that mutation of Glu175 to Gly extended the structure of Xenorhabdus Luminescence luciferase, locally.

• BMB Reports
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• v.35 no.5
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• pp.488-493
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• 2002

IgY was separated from a hen's egg yolk that was immunized with Helicobacter pyroli. The anti-H. pyroli IgY activity at acidic pH and the suppressive effect of polyol on acid-induced inactivation of IgY were investigated. Sorbitol and xylitol were used as polyols. IgY was quite stable at pH 5~7. Irreversible inactivation of IgY was observed at pH below 4, and proceeded rapidly at pH below 3. The acid stability of IgY was enhanced in the presence of 30% sorbitol or above. In a 50% aqueous sorbitol solution, an acid-induced inactivation was almost completely suppressed at pH 3. However, the improvement of IgY activity was not observed in the aqueous xylitol solution. IgY showed almost the same activity as native IgY when sucrose was substituted for sorbitol. On the other hand, the xylitol replacement with sucrose did not enhance the acid stability of IgY. The acid-induced inactivation of IgY was related to tryptophyl fluorescence. Fluorescence emission spectra suggested that structural changes near the tryptophan residues may occur under acidic conditions. An increase in sorbitol concentration induced a blue shift. The fluorescence emission of IgY in a 50% sorbitol solution had a peak at 330 nm, which was the same emission peak that was exhibited by native IgY. Sorbitol could, therefore, be used as a good stabilizer of IgY under acidic conditions.

• BMB Reports
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• v.35 no.4
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• pp.389-394
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• 2002

$[Ru(bpy)_2(dppz)]^2+$ (bpy=2,2'-bipyfidine, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuBD), a long-lifetime metal-ligand complex, displays favorable photophysical properties. These include long lifetime, polarized emission, but no significant fluorescence from the complex that is not bound to DNA. To show the usefulness of this luminophore (RuBD) for probing the bending and torsional dynamics of nucleic acids, its intensity and anisotropy decays when intercalated into supercoiled and relaxed pTZ18U plasmids were examined using frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetimes for the supercoiled plasmids (< $\tau$ >=148 ns) were somewhat shorter than those for the relaxed plasmids (< $\tau$ >=160 ns). This suggests that the relaxed plasmids were shielded more efficiently from water. The anisotropy decay data also showed somewhat shorter slow rotational correlation times for supercoiled plasmids (288 ns) than for the relaxed plasmids (355 ns). The presence of two rotational correlation times suggests that RuBD reveals both the bending and torsional motions of the plasmids. These results indicate that RuBD can be useful for studying both the bending and torsional dynamics of mucleic acids.

• Polymer(Korea)
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• v.32 no.1
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• pp.56-62
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• 2008

Three types of network polyesters have been newly synthesized by a two-step condensation reaction by the various combination of several diols and diacids. When these polymer films were thermally treated at $240^{\circ}C$, they exhibited absorptions in a visible range despite the forbidden transition of carbonyl group. When excited at wavelengths above 330 nm, the polymers showed fluorescences in a wide visible range from blue to near yellow. These fluorescence phenomena are due to the formation of certain conjugated structures by the Knoevenagel type self-condensation under the high-temperature thermal treatment. These polymers showed significant difference in the thermal properties as a function of the degrees of chemical crosslinking. They also underwent photodegradation. Highly resolved, fluorescent image patterns were successfully obtained by the photodegradation of malonate group under a strong UV-light irradiation.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.821-828
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• 2016

We examed physiological and flowering response of S. capitata, the endangered plant in Korea, under LED light conditions in plant factory to cultivate artificially for conservation. We cultivated S. capitata and measured its physiological responses and the number of flowers under red, blue, white, red+far-red mixed, red+blue mixed, and red+blue+white mixed light. The results showed that its photosynthetic rate and chlorophyll content were recorded relatively high in red+blue+white and red+blue mixed light respectively. Transpiration rate and stomatal conductance appeared relatively high in the white single light while water use efficiency was no difference. Photochemical efficiency of photochemical photosystem II by minimum and maximum chlorophyll fluorescence was the highest in the red+blue+white mixed light condition than other ones. The number of flowers of S. capitata was at its peak under the red light or red+far-red mixed light. Therefore, we conclude that the most efficient way to grow for flowering of S. capitata is to provide red light or red+far-red mixed light in the plant factory.