• YAKHAK HOEJI
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• v.9 no.1_2
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• pp.18-22
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• 1965

A new organic reagent, 1-isonicotinoyl-2-furfurylidene hydrazine was synthesized from isonicotinic acid hydrazide and furfural, gives precipitate with copper(II), mercury(II) and argent(I), whereas, it gives a water soluble yellow complex with iron(III). Copper complex of the reagent is soluble in EtOH MtOH, pyridine, dioxane and dimethylformamide with green yellow coloration. The complex has a maximum absorption at 385 m.$\mu$ and molar ratio of copper; reagent was estimated as 1:1 by continuous variation method, slop method and chelate titration method. Molar extinction coefficient (9600) and apparant formation constant of this complex was spectrophotometrically determined. K=1.7 * $10^{7}$ (Babko's method) K=2.1 * $10^{7}$ (Anderson's method). This reagent reacted with copper so sensitive that it would be available for determination of Cu (II).

• YAKHAK HOEJI
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• v.32 no.4
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• pp.251-257
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• 1988

A simple and sensitive HPLC method was developed for the simultaneous determination of ten kinds of active ingredients formulated in commercial cough-cold mixtures. A group of Pseudoephedrine HCl, dl-Methylephedrine HCl, Noscapine, Chlorophenylamine maleate, Dextromethorphan HBr and Phenylpropanolamine HCl were determined at 254nm using a Novapak $C_{18}$ column with mobile phase consisting of a mixture of methanol-acetonitrile-1, 4dioxane-tetrahydrofuran-water(12 : 20 : 20 : 5 : 43, pH4.7) containing 0.013M-dioctyl sodium sulfosuccinate. The another group of Acetoaminophen, Caffeine, Guaifenesin and Ethenzamide were also determined at 254nm using a Novapak $C_{18}$ column as the stationary phase, and a mixture of methanol-1% aqueous acetic acid (3 : 7). The results indicate that these methods are accurate and precise with relative standard deviation of not more than 1% (n=5) for the above active ingredients.

• Journal of Environmental Science International
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• v.13 no.9
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• pp.835-843
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• 2004

N,N-bis(2-salicylaldehyde)dipropylenetriamine(5- Hsaldipn), N,N-bis( 5-bromosalicyl-aldehyde) dipropylenetriamine (5-Brsaldipn), N,N-bis(5-chlorosalicy laldehyde )dipropylene-triamine(5-Clsaldipn), N,N-bis(2-hydroxy- $5-methoxy-benzaldehyde)dipropylenetriamine(5-OCH_3saldipn)$ and N,N-bis (2-hydroxy-5-nitrobenzaldehyde)dipropylenetriamine $(5-NO_2saldipn)$ were synthesized and characterized by elemental analysis, infrared spectrometry, NMR spectrometry and mass spectrometry. Their proton dissociation constants were determined in 70% dioxane/30% water solution by potentiometric. Stability constants of the complexes between these ligands and the metal ions such as Cu(II), Ni(II) and Zn(II) were measured in dimethyl sulfoxide by a polarographic method. Stability constants for the ligands were in the order of $5-OCH_3$ > 5-H > 5-Br > 5-Cl > $5-NO_2$ saldipn. Enthalpy and entropy changes were obtained in negative values.

• YAKHAK HOEJI
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• v.37 no.3
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• pp.286-289
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• 1993

UV and high performance liquid chromatographic methods for the quantitative analysis of methyl 5-hydroxy-dinaphtho [1,2-2',3'] furan-7,12-dione-6-carboxylate(MHDDC) in urine and blood were developed. The correlation coefficients of the calibration curves of MHDDC in chloroform, methanol and dioxane solution were 0.999, 0.997 and 0.998, respectively. MHDDC was resolved within 15 min and had a detection limit of 2-5ng at S/N=3 by using a reversed-phase column with two solvents (MeOH, HAc).

• Korean Journal of Pharmacognosy
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• v.21 no.3
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• pp.239-241
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• 1990

A new method for quantitative determination of byakangelicin in Angelicae dahuricae Radix by high performance liquid chromatography was established. A reversed-phase system with a ${\mu}Bondapak$ $C_{18}$ column using THF : dioxane : MeOH : HAc : 5% $H_3PO_4$ : $H_2O$=72.5 : 62.5 : 25 : 10 : 1 : 329 as a mobile phase was developed. Byakangelicin together with ter-O-byakangelicin and oxypeucedanin methanolate, and isooxypeucedanin as an internal reference were detected at 350 nm and the analysis was successfully carried out within 30 min.

• Journal of Photoscience
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• v.6 no.4
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• pp.159-163
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• 1999

The fluorescence quenching of 2-phenyl-5-(4-biphenylyl)-1,3,4-oxadiazole (PBD) and 1,4-di-[2-(5-phenyloxazolyl)]-benzene (POPOP) by aniline has been carried out in different solvent mixtures of dioxane and acetonitrile at room temperature. The quenching is found to be appreciable and a positive deviation from linearity was observed in the Stern-Volmer plot in all the solvent mixtures. Various rate constants for the quenching processes have been determined using a modified Stern-Volmer equation. From the positive deviations of linear Stern-Volmer plots and the dependence of rate constants on the polarity of the solvents, it has been concluded that both static and dynamic quenching processes are responsible for the observed positive deviation in the Stern-Volmer plot.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.8-14
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• 1999

A screening has been performed to find hyper-ligninolytic fungi, which degtrade beech and pine lignin extensively in order to broaden the understanding of the ligninolytic enzymes elaborated by various white-rot fungi. One hundred and twenty two ligninolytic strains were selected from decayed woods with a selective medium for screening ligninolytic wood-rotting fungi. Two of them, Phanerochaete sordida YK-624 and YK-472, showed much higher ligninolytic activity and selectivity in beech-wood degradation than typical lignin-degrading fungi, phanerochaete chrysosporium and Coriolus versicolor. They also degraded birch dioxane lignin and residual lignin in unbleached kraft pulp(UKP) much more extensively than P. chrysosporium and C. versicolor. During fungal treatment of beech wood-powder, the fungus strain P. sordida YK-624 showed higher activity of extracellular manganese peroxidase (MnP) in the medium than P. chrysosporium. It also showed MnP activity, which would not be lignin peroxidast during treatment of oxygen-bleached kraft pulp(OKP) and under enzyme-inducing conditin.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.11a
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• pp.192-194
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• 2005

O$_3$/H$_2$O$_2$ 고급산화공정에서 1,4-D의 제거는 반응시간에 따라 완만하게 감소하였으나, O$_3$/catalyst 고급산화공정에서는 전체 제거량의 약 50${\sim}$75%가 반응 초기 5분 내에 제거되어 O$_3$/H$_2$O$_2$ 공정에 비해 초기 반응속도가 현저히 빠른 것을 알 수 있었다. O$_3$/H$_2$O$_2$ 고급산화공정은 ${\Delta}$TOC/${\Delta}$ThOC의 비는 0.09${\sim}$0.40으로 나타났으며, O$_3$/catalyst 고급산화공정에서는 ${\Delta}$TOC/${\Delta}$ThOC의 비가 0.68${\sim}$0.98로 나타나 O$_3$/catalyst 고급산화공정이 O$_3$/H$_2$O$_2$ 고급산화공정에 비해 유기물의 산화력이 우수한 것으로 확인되었다.

• Macromolecular Research
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• v.8 no.3
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• pp.142-146
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• 2000

Hyperbranched poly(ether sulfone) analogs with the 1,3,5-s-triazine moiety were prepared by the direct polymerization of AB$_2$type monomer, 2,4-bis(4-hydroxyphenyl)-6-(4-(4-(4-fluorobenzenesulfonyl)phenoxy)phenyl)-1,3,5-s-triazine (3). The selective reactivity of three chlorine atoms on cyanuric chloride toward nucleophiles provides an efficient route for the systematic synthesis of AB$_2$type triazine monomers and their hyperbranched polymers. The triazine rings influenced the structural and material characteristics of these hyperbranched polymers. The hyperbranched poly(ether sulfone) analog4 showed a glass transition at 295$^{\circ}C$. and was soluble in THF, 1,4-dioxane, and DMSO. An excellent thermal stability of polymer 4 was exhibited by a TGA analysis, which showed that 5% weight loss occurred at 480$^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.12 no.2
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• pp.145-150
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• 1995

The Kinetics velocity for hydrolysis reaction of vanillylidene imine derivatives has been measured by ultra-violet ray spectrophotometer in 20wt% $dioxane-H_2O$ at $25^{\circ}C$. It was measured the reaction rate Constant of vanillylidene imine derivatives that can be applied widely following to pH-change at $25^{\circ}C$. Final products that hydrolyzed the vanillylidene imine certified in vanillin and aniline derivative, and the effect of substitution radical that has affected on hydrolysis reaction was largely promoted to reaction rate by electron attrating group in acidity and electron donoring group in basic. From the results of rate constant to hydrolysis reaction, substituent radical effect and final products. It has certified the hydrolysis reaction mechanism of vanillylidene imine derivatives.