• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1214-1217
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• 2012

One Helicosporium strain, isolated from a wilted chestnut tree, evidenced in vitro antimicrobial activity against various types of bacteria and fungi, and generated a diffusible pigment. The antimicrobial compounds and the diffusible pigment of the Helicosporium sp. isolate were purified via solvent fractionation, column chromatography, and recycling preparative chromatography. Both the major antimicrobial compound and the diffusible pigment were identified as 2-methylresorcinol via nuclear magnetic resonance spectroscopy. Therefore, 2-methylresorcinol, a diffusible pigment generated by Helicosporium sp., appears to be an active antimicrobial principle. This pigment also exhibited considerable cytotoxicity against mammalian cells.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.177-182
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• 2006

Polyphenol oxidase (PPO) was isolated from the flesh of Fuji apples by DEAE-Cellulose, ammonium sulfate precipitation, phenyl-Sepharose CL-4B, and Sephdex G-100 chromatography. The molecular mass of the purified PPO was estimated to be 40 kDa by SDS polyacrylamide gel electrophoresis. With regard to substrate specificity, maximum activity was achieved with chlorogenic acid as substrate, followed by catechin and catechol whereas, there was no detectable activity with hydroquinic acid, resorcinol, or tyrosine as substrate. The optimum pH and temperature with catechol as substrate were 6.5 and $35^{\circ}C$, respectively. The enzyme was most stable at pH 6.0 and unstable at acidic pH. The enzyme was stable when it was heated to $45^{\circ}C$ but heating at $50^{\circ}C$ for more than 30 min caused 50% loss of activity. Reduced $ZnSO_4$, L-cystein, epigallocatechin-3-o-gallate (EGCG), and gallocatechin gallate (GCG) also inhibited activity.

• Journal of the Korean Wood Science and Technology
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• v.37 no.2
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• pp.155-163
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• 2009

This study examined the thermal stability of PLA-WF bio-composites. Wood flour (WF)-filled PLA bio-composites were reinforced with the flame retardants, Melamine pyrophosphate (MPP), resorcinol bis (diphenyl phosphate) (RDP) and zinc borate (ZB). The flame retardant was compounded with PLA and natural biodegradable filler. The thermal properties of the biodegradable polymer and bio-composites reinforced with the flame retardant were measured and analyzed by DSC, DMA and TGA. The results showed that the flame retardant-reinforced biodegradable bio-composite exhibited improved thermal properties.

• Journal of the Korea Furniture Society
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• v.25 no.3
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• pp.233-237
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• 2014

The eco-friendly preservatives such as ACQ or CUAZ have been used in landscape architectural facilities these days. In this study, the decay efficacies of ACQ treatments were evaluated according to domestic veneer species, concentration of ACQ, weathering test, adhesive type, and fungus type. In case of veneer species, hinoki cypress and yellow poplar showed the highest and lowest decay resistance, respectively. And the decay resistance appeared to be greater in plywoods bonded by resorcinol resin-bonded plywood and non-weathering treated plywood than polyurethane resin-bonded plywood and weathering treated plywood.

• Journal of the Korean Ceramic Society
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• v.45 no.11
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• pp.662-666
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• 2008

Electrochemical properties of carbon cryogel electrode for the application of composite electrode materials mixed with metal oxide in supercapacitor have been studied. Carbon cryogels were synthesized by sol-gel polycondensation of resorcinol with form aldehyde, followed by a freeze drying, and then pyrolysis in an inert atmosphere. Physical properties of carbon cryogel were characterized by BET, X-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that carbon cryogel is amorphous material. The electrochemical properties of carbon cryogel were measured by cyclic voltammetry as a function of concentration of liquid electrolyte, galvanostatic charge-discharge with different scan rates and electrochemical impedance measurements. The result of cyclic voltammetry indicated that the specific capacitance value of a carbon cryogel electrode was approximately 150.2 F/g (at 5 mV/s in 6M KOH electrolyte).

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.61-64
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• 2000

Three kinds of treeing inhibitors are added to investigate the effect on electrical properties of XLPE. The treeing inhibitors are barbituric acid, 4- (4-Nitrophenylazo) resorcinol and 4-(4-Nitrophenylazo) naphthol. Added amount of each treeing inhibitors varied form 0phr to 2.0phr. In order to know the changes of electrical properties, break down strength, tan$\delta$, and $\varepsilon$$_{r}$ were measured. Experimental results showed that electrical properties of each sample was slightly changed by amount of additives.s.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.483-486
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• 1999

The treeing inhibitors of barbituric acid derivatives and azocompounds effects on the electrical properties of crosslinked low density polyethylene were investigated. The electrical treeing parameters for tree inception voltage, AC breakdown strength. volume resistivity, capacitance and dissipation factor at 1Mz and thermoluminescence measurements were discussed. From the results, 4- (4-nitrophenylazo) resorcinol among the treeing inhibitors was shown good insulation characteristics.

• Textile Coloration and Finishing
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• v.9 no.6
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• pp.68-73
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• 1997

Urea/formaldehyde(UF) and melamine/formaldehyde(MF) microcapsules containing perfume and 2,4,4'-trichlroro-2-hydroxydiphenyl ether(DP) were prepared by the in-situ polymerization using urea and formaldehyde. Effects of dispersing agent, accelerating agent, formaldehyde, agitation speed on the mean diameter of microcapsules were investigated. The diameter of microcapsule was decreased with increasing dispersing agent concentration. A slight increase in the diameter was observed when the concentration of film forming material was increased. The diameter of microcapsule was decreased with increasing agitation speed up to 8,000rpm. The mean diameters of UF microcapsule prepared at 8,000rpm are about 3$\mu$m. A slight decrease in the diameter was observed when the concentration of resorcinol was increased.

• Bulletin of the Korean Chemical Society
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• v.15 no.3
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• pp.193-197
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• 1994

Due to possibility of visual observation of phase transformations and processes during solidification, the transparent binary alloy models are important in materials and metallurgical sciences. As such, phase diagram, linear velocity of crystallization, microstructure and spectral behaviour of binary organic systems of benzidine with resorcinol and catechol involving formation of addition compound with congruent melting point have been studied. While their phase diagrams show the formation of two eutectics and a 1:2 (B:RC, B:CT) addition compound in each case, the crystallization data obey the Hillig-Turnbull equation. The microstructural investigations give the characteristic morphology of the eutectics and the addition compounds, the spectral studies suggest intermolecular hydrogen bonding between two components forming the molecular complex.

• Bulletin of the Korean Chemical Society
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• v.15 no.3
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• pp.198-204
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• 1994

Chemical shifts in aqueous sodium dodecylsulfate(SDS) micellar solution solublizing phenol, catechol, resorcinol, hydroquinone have been measured to investigate solubilization properties. Proton nuclear magnetic resonance frequencies of solubilizates as well as those of the ${\alpha}$-methylene, middle methylene and terminal methyl of SDS shift linearly as a function of solubilizate concentration. From the plots of observed chemical shift (v) vs solubilizate concentration, slope (a) and solubilizate free chemical shift ($v_0$) are obtained. They are very informative to solubilization site of the systems. Catechol and phenol solubilized SDS and catechol solubilized dodecylpyridinium chloride(DPC), dodecyltrimethylammonium bromide(DTAB) systems are studied using the same method to compare head group effect and middle methylene proton signal splitting. It is proposed that phenol and catechol are inserted into micellar interior and the number of methylenes assigned to the higher field peaks is 5.0${\pm}$0.5.