• Bulletin of the Korean Chemical Society
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• 제28권7호
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• pp.1171-1174
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• 2007

We have developed an electrochemical immunosensor that combines the electrocatalytic property of carbon nanotube and the low background current of indium tin oxide (ITO) electrode. A partial monolayer of carboxylated single-walled carbon nanotube (CCNT) is covalently formed on an ITO electrode modified with amine-terminated phosphonic acid. Nonspecifically adsorbed avidin on the hydrophobic sidewalls of CCNT is used to immobilize biotinylated antibody and to reduce the nonspecific binding to CCNT. The biotinylated antimouse IgG bound on avidin and the antimouse IgG conjugated with alkaline phosphatase (ALP) sandwiches a target mouse IgG. ALP catalyzes the conversion of p-aminophenyl phosphate monohydrate into p-aminophenol, which is electrocatalytically oxidized to p-quinone imine on CCNT surface. Moderate electrocatalytic electrode obtained with the combination of CCNT and ITO allows low detection limit (0.1 ng/ mL).

• 약학회지
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• 제23권3_4호
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• pp.133-140
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• 1979

The adsorption of erythrosine in the aliphatic alcohols by antibiotics such as ampicillin anhydrous, ampicillin trihydrate, amoxicillin trihydrate, cephalexin monohydrate was studied. The adsorption isotherms were all described with Freudlich equation. From the various experimerts, it was found that the adsorption of erythrosine by antibiotics in the aliphatic alcohols was affected by the solubility of adsorbents. The adsoption in the mixture of aliphatic alcohols and water is related with the dielectric constant of mixed solvents. According to increase in the pH values of aqueous solution, the adsorption of erythrosine for antibiotics is decreased, but increased in the mixture of aliphatic alcohols and water. The adsorption of erythrosine in the suspension of antibiotics showed a correlation with the temperature. Colloidal silica which is used as stabilizer had a favorable effect on the adsorption of erythrosine in the suspension of antibiotics.

• 대한화학회지
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• 제33권6호
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• pp.577-581
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• 1989

황산구리 수용액에 과량의 아연을 반응시켜 만든 구리-아연은 히드라진 존재하에서 방향족 니트로 화합물을 아미노 화합물로 환원시키는데 좋은 촉매작용을 보여주었다. 그러나 지방족 니트로 화합물의 환원반응은 진행되지 않았다.

• 한국임상수의학회지
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• 제15권2호
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• pp.291-302
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• 1998

Four out of 15 dogs were successfully induced diabetes mellitus with intravenous iqiection of 30 mg of streptozotgin and 50 mg of alloxan monohydrate per kilogram body weight and maintained more than 9 weeks without iqiection of insulin or oral hypoglycemic sgent Histopathologicallyi these four dogs have typical diabetic lesions such as degeneration and vacuolation of pancreatic islet cells, and fatty change of liver at necropsy in the end of study. Serum glucose level increased dramatically at 24 hours post-injection but serum fructosamine level increased gradually and reached plateau at 31-41 days post-injection of streptozotocin and alloxan. Serum fructosamine concert%lion correlated very well with serum glucose concentration of preceding 4-7 weeks in experimentally induced diabetic dogs. Our data suggest that serum fructosamine reflects mean glucose concentration of preceding 4-7 weeks in experimentally induced diabetic dogs.

• Natural Product Sciences
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• 제14권1호
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• pp.68-72
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• 2008

A simple reversed phase HPLC method was developed for extracting pharmacologically active compounds coptisine, palmatine, berberine, and epiberberine from the roots of Coptis chinensis using a binary gradient of acetonitrile : 10 mM hexanesulfonic acid-Na monohydrate with UV detection at 254 nm. The coptisine (1), palmatine (2), berberine (3), and epiberberine (4) contents of the roots of C. chinensis collected from sixteen district markets in Korea and China were $6.79\;{\sim}\;24.63\;{\mu}g/g$, $5.40\;{\sim}\;20.75\;{\mu}g/g$, $21.40\;{\sim}\;81.21\;{\mu}g/g$, and $3.45\;{\sim}\;12.04\;{\mu}g/g$, respectively.

• 대한본초학회지
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• 제25권1호
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• pp.1-7
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• 2010

Objectives : We investigated genetic toxicity of HMCO5 in relation to chromosome aberration test on Cultured Chinese Hamster Lung (CHL) in the presence and absence of S-9 mix. Methods : Experimental groups were divided into two groups: with S-9mix (+S) or without S-9 mix (-S). -S group was also divided 2 series by treatment hours (6 hr: 6-S; or 24 hr; 24-S). Each group treated with vehicle only (complete culture medium), HMCO5 (1,250, 2,500, $5,000\;{\mu}g/ml$), and cyclophosphamide monohydrate (CPA) and ethylmethanesulfonate (EMS), respectively. Results : HMC05 did not show any aberrant metaphase. However, there were significant (p < 0.01) aberrant metaphases with CPA in S+ and with EMS in S-. Conclusions : These results indicate that HMC05 formula does not show any toxicity in chromosome aberration test.

• Bulletin of the Korean Chemical Society
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• 제29권3호
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• pp.604-608
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• 2008

A series of N-alkenyl pyrrolidine-2-thiones were synthesized by the reaction between pyrrolidine-2-thione and various aldehydes such as n-propanal, isopropanal, n-butanal, n-hexanal, n-octanal and phenylacetaldehyde in 32-86% yields using microwave irradiation technique. Only one structural E isomers were predominantly formed within 15 minutes in chlorobenezene?/p-toluenesulfonic acid monohydrate.

• Macromolecular Research
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• 제16권7호
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• pp.659-662
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• 2008

A new and useful poly(ethylene oxide)-based pH-sensitive block copolymer is introduced. Poly(ethylene oxide-b-N-phenylmaleimide) was first synthesized by anionic polymerization of N-phenylmaleimide (N-PMI) using mixed alkali metal polymeric alkoxide by sequential monomer addition method in the mixture of benzene/THF/DMSO (10/5/3, v/v/v) at room temperature. Reductive deimidation of the resulting block copolymer was performed using hydrazine monohydrate leading to the formation of the corresponding pH-sensitive poly(ethylene oxide-b-maleic acid).

• Elastomers and Composites
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• 제53권2호
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• pp.75-79
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• 2018

ZnS:Mn-glycine (ZnS:Mn-Gly) nanocomposites were synthesized by capping ZnS:Mn nanocomposites with glycine. Zinc sulfate heptahydrate ($ZnSO_4{\cdot}7H_2O$), glycine ($C_2H_5NO_2$), manganese sulfate monohydrate ($MnSO_4{\cdot}H_2O$), and sodium sulfide ($Na_2S$) were used as the source reagents. $ZnS:Mn-Gly-C_{60}$ nanocomposites were obtained by heating the ZnS:Mn-Gly nanocomposites and fullerene ($C_{60}$) at a 2:1 mass ratio in an electric furnace at $700^{\circ}C$ for 2 h. X-ray diffraction (XRD) was used to characterize the crystal structure of the synthesized nanocomposites. The photocatalytic activity of the $ZnS:Mn-Gly-C_{60}$ nanocomposites was evaluated, via the degradation of brilliant green (BG) dye under 254 nm irradiation, with a UV-vis spectrophotometer.

• 한국결정성장학회지
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• 제22권2호
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• pp.84-91
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• 2012

Single and few-layer graphene nanosheets (GNs) have successfully synthesized by a modified Hummer's method followed by chemical reduction of exfoliated graphene oxide (GO) in the presence of hydrazine monohydrate. GO and GNs were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), X-ray diffractions (XRD), Raman spectroscopy, Transmission electron microscopy (TEM), Atomic force microscopy (AFM), Optical microscopy (OM) and by electrical conductivity measurements. The result showed that electrical conductivity of GNs was significantly improved, from $4.2{\times}10^{-4}$ S/m for GO to 12 S/m for GNs, possibly due to the removal of oxygen-containing functional group during chemical reduction. In addition, the $NO_2$ gas sensing characteristics of GNs are also discussed.