• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.338-341
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• 1986

Hydrocarbon solution of $Ir(PPh_3)_2(CO)OClO_3$ reacts with $Ph_2PC_6H_4$-o-CHO and 3-methyl-2-aminopyridinyl aldimine to yield ${\bar{Ir(Ph_2PC_6H_4-o-CO)}}\;(PPh_3)_2(CO)(H)ClO_4$(1) and ${\bar{Ir(NC_6H_6NC}}C_6H_5)(PPh_3)_2(CO)(H)ClO_4$(2), respectively. The compound $Ir(PPh_3)_2N_2Cl$ also reacts with $Ph_2PC_6H_4$-o-CHO and 3-methyl-2-aminopyridinyl aldimine to give ${\bar{Ir(Ph_2PC_6H_4-o-C}}O)(PPh_3)_2(H)Cl(3)$ and $Ir(NC_6H_5NCC_6H_5(PPh_3)_2(H)Cl(4)$, respectively. Compounds 1, 2, 3, and 4 were characterized by infrared, $^1H$ NMR, $^{31}p$ NMR, UV spectra, and conductivity measurements.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.11a
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• pp.141-143
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• 1993

A nontoxic organic photoreceptor for near infrared light has been developed. A double layered photoreceptor using $\tau$-H$_2$Pc as the CGL was made. The CTL was formed by oxadiazole derivative dispersed in two other host polymers. This photoreceptor has a charge acceptance of -900 V when a corona charge is used, and has residual potentials of -20 V for PC, and -10 V for PVB by light irradiation.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.343-348
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• 2008

In this study, antioxidant activity of methanol extract of Glycyrrhiza uralensis Fisch (GUE) against $H_2O_2$-induced DNA damage in human leucocytcs and cell death in PC12 cells was determined. The effect of GUE on $H_2O_2$-induced DNA damage in human leucocytcs was evaluated by the comet assay, where GUE ($1-50\;{\mu}g/mL$) was a dose dependent inhibitor of DNA damage induced by $H_2O_2$. The protective effect of GUE against $H_2O_2$-induced damage on PC12 cells was investigated by MTT reduction assay and lactate dehydrogenase release assay. A marked reduction in cell survival induced by $H_2O_2$ was significantly prevented by $1-50\;{\mu}g/mL$ of GUE. The enzyme activity of caspase-3 was elevated in $H_2O_2$-treated PC12 cells, while preincubation with GUE for 30 min inhibited $H_2O_2$-induced caspase-3 activation in a dose-dependent manner. In conclusion, GUE ameliorates $H_2O_2$-induced DNA damage in human leucocytes and has neuroprotective effect by preventing cell death in PC12 cell, suggesting that GU may be a potential candidate for novel therapeutic agents for neuronal diseases associated with oxidative stress.

• Korean Journal of Microbiology
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• v.17 no.1
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• pp.42-48
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• 1979

Cellulases were isolated from both healthyl(PC) and virus0infected penicillum chrysogenum(PCV) in the wheat bean culture, and some properties of the enzymes were studied. 1) At $37^{\circ}C$, pH 6, 4 and 6day's culture the maximal enzyme yield was obtained in both PC and PCV. 2) The optimum temperature for the PC cellulase was at $50^{\circ}C$, and that for the PCV enzyme was the same. 3) The optimum pH for the PC enzyme was at 5.0, whereas the PCV enzyme was at 6.0, indicating that they are isozymes. 4) When Na-CMC was used as a substrate, PC enzyme was twice as high as the activity of PCV enzyme.

• Bulletin of the Korean Chemical Society
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• v.19 no.5
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• pp.565-568
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• 1998

Novel mononuclear metal complexes with the formula $[M(Ph_2PC_6H_4NC_3H_6NC_6H_4PPh_2)]$ (M=Pd (1); M=Pt (2)) were obtained when N,N'-bis[2'-(diphenylphosphino)phenyl]propane-1,3-diamine, I was mixed with cisdichlorobis(diethylsulfide)palladium and platinum in the presence of NEt3. Two mononuclear metal compounds with the fomula [M(Ph2PC6H4NH)(SEt2)Cl] (M=Pd (3); M=Pt (4)) were synthesized from $M(SEt_2)2Cl_2$ and N-(2'-diphenylphosphinophenyl)-4-amino-1,1,1,5,5, 5-hexafluoro-3-penten-2-one, II by the elimination reaction of hexafluoro pentenone. The X-ray single crystal structures of 1 and 4 are described. X-ray single crystal diffraction analyses reveal that compound 1 is a mononuclear palladium compound with P,N,N,P-coordination mode and 4 is a mononuclear platinum compound with P,N-coordination mode.

• Journal of Sensor Science and Technology
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• v.7 no.4
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• pp.254-262
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• 1998

Multilayer Langmuir-Blodgett (LB) films coated on quartz crystal microbalance (QCM) of octa-substituted metallophhtalocyanines ($MPc(OEH)_8$, M = Cu, Co, and Sn) and dihydrogen phthalocyanines ($H_2Pc(OEH)_8$) were used to quantify $NO_2$ concentrations. They were exposed to various concentrations of $NO_2$ in dry $N_2$. Among the four phthalocyanines we tested, the metal-free $H_2Pc(OEH)_8$ was observed to be most sensitive to $NO_2$. However, its LB film showed a partially irreversible behavior, that is part of the frequency change due to $NO_2$ adsorption could not be recovered even after purging with pure $N_2$ gas for an extended period. Examining the spectra of NMR and FTIR revealed fact that the irreversible portion of frequency change was due to ether groups in the linkage between side chains and the Pc unit. In order to remove the effect of such initial deactivation, on $NO_2$ quantification experiment, a freshly fabricated LB film was treated at a high concentration of $NO_2$ so that the ether sites were saturated. A pretreated LB film showed a reproducible performance for repeated uses. The $CuPc(OEH)_8$ LB film showed a satisfactory sensing performance down to as low as 4 ppm. For the $H_2Pc(OEH)_8$ LB film, the lower detection limit was found to be 35ppb of $NO_2$. In order to make the experimental condition more realistic, the carrier gas, dry nitrogen, was replaced by air. It was observed that the presence of oxygen, a weak electron acceptor, reduced the sensitivity and thus increased the sensing limit to hundreds of ppb. Results of experiments with moisture added showed that the interference of moisture was quite severe.

• Korean Journal of Veterinary Research
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• v.46 no.2
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• pp.87-96
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• 2006

We established an in vitro experimental system using the following procedure. We first introduced tritium-labeled norepinephrine ([$^3$H]-NE) into PC12 cells, The [$^3$H]-NE incorporated into PC12 cells were then stimulated by a high concentration (60 mM) of $K^+$ buffer during 12 minutes. Then, we collected $100{\mu}l$ supernatant and counted the amount of [$^3$H]-NE release from PC12 cells with a scintillation counter. After screening fungal, Streptomyces spp. or bacterial product using this experimental sytem, we obtained FS11052 from Streptomyces spp. which inhibited [$^3$H]-NE release from PC12 cells. FS11052 also inhibits the release of ATP as a neurotransmitter of PC12 cells and rat cortical neurons, The inhibitory effect was seen even when the PC12 cells were treated with low $K^-$ buffer containing ionomycin ($1{\mu}M$) as an ionopore. This result suggests that the inhibitory action of FS11052 on neurotransmitter release appeared after the influx of $Ca^{2+}$.

• Food Science of Animal Resources
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• v.39 no.4
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• pp.541-554
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• 2019

Processed cheeses (PCs) were made under varying cooking pH values (5.3, 5.4, 5.5, and 5.6) using a processed cheese cooker. Along with emulsifying salts (2.5%), distilled water, NaCl (2%) and a colouring agent under these cooking pH values, the PC samples made with either 100% fresh curd and rennet casein coded processed cheese control ($PC_C$) as control or ~70% fresh curd-~30% traditional village cheese coded processed cheese with village cheese ($PC_V$). The main aim of this study was to determine the effect of the varying cooking pH values on the textural properties for the PCv samples compared with the control sample during 90 days of storage. Chemical and textural properties of all PC samples were investigated over time. The chemical compositions of the PC samples (dry matter and ash) increased at d 90 of storage significantly, due to 1-d ripening of all PC samples at ambient temperature in terms of the manufacturing protocol of the cheese. The textural properties of the PC samples were altered by the varying cooking pH values. It may propose that the interactions of the proteins at the cooking pH values during processing and biochemical mechanisms in the cheese systems could likely affect the texture of the PC samples over time. Hardness, gumminess and chewiness values of all PC samples also increased over time (p<0.05). This study is also to give some knowledge on the design of PC manufacture to cheese makers, and a marketing opportunity to local cheese makers who individually make a traditional village cheese in Turkey.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.36T no.3
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• pp.19-25
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• 1999

The photoreceptor films with double layer structure were prepared by the plasma polymerization and the dip-coating method. The blocking layer was coated with A1$_2$O$_3$ on the Al substrate and the charge generation layer was formed by H$_2$ phthalocyanine (H$_2$Pc). Poly 9-Vinylcarbazole was used as a charge transport layer. H$_2$Pc film prepared by the vacuum evaporation had absorption peaks on 613.6[nm] and 694.8[nm], and H$_2$Pc film prepared by the plasma polymerization had a dull peaks between 600 and 700[nm]. The surface potential of PVCz increased with increasing the applied voltage and the thickness of PVCz. The dark decay characteristic, the light decay time and the residual time increased with increasing the thickness of PVCz. The surface charge of PVCz of 15[${\mu}{\textrm}{m}$] thickness was 134[nc/$\textrm{cm}^2$] at the surface potential of -600[V] and the charge generation efficiency of H$_2$Pc was 0.034.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.220-220
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• 2006

Rheological and electrical properties of the polycarbonate (PC) / multi-walled carbon nanotube (MWNT) were studied. The MWNT was funtoinalized by treating with the hydrogen peroxide ($H_{2}O_{2}$). The electrical conductivity showed higher value for the PC/MWNT ($H_{2}O_{2}$ treated, freeze drying) composites compared that of the PC/MWNT ($H_{2}O_{2}$ treated, thermal drying) composites. From the results of the morphological, rheological, and electrical properties of the PC/MWNT composites, it is suggested that the electrical and rheological properties of the PC/MWNT composites are affected by the MWNT-MWNT network structure which is related with the MWNT morphologies such as the degree of aggregation and aspect ratio of the MWNT.