• Korean Journal of Microbiology
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• v.55 no.3
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• pp.286-288
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• 2019

Pseudomonas parafulva PpaJBCS1880 (PpaJBCS1880) isolated from rice seeds showed strong antagonistic activity against bacterial plant pathogens by producing lipopeptide. Furthermore, the strain controlled the incidence of bacterial pustule in soybean plants and promoted the growth of rice plants. Here we present complete genome sequence of PpaJBCS1880. The genome comprises of 5,208,480 bp with GC content of 63.4%, which includes 4,487 predicted protein-coding genes, 19 rRNAs, and 74 tRNAs. Genome analysis revealed genes encoding antimicrobial secondary metabolites such as lipopeptide, pyoverdine, phenazine, and hydrogen cyanide, which are known to play essential roles in biocontrol of plant diseases.

• Molecules and Cells
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• v.21 no.1
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• pp.161-165
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• 2006

Dichlorodihydrofluorescein ($DCFH_2$) is a widely used probe for intracellular $H_2O_2$. However, $H_2O_2$ can oxidize $DCFH_2$ only in the presence of a catalyst, whose identity in cells has not been clearly defined. We compared the peroxidase activity of Cu,Zn-superoxide dismutase (CuZnSOD), cytochrome c, horseradish peroxidase (HRP), $Cu^{2+}$, and $Fe^{3+}$ under various conditions to identify an intracellular catalyst. Enormous increase by bicarbonate in the rate of $DCFH_2$ oxidation distinguished CuZnSOD from cytochrome c and HRP. Cyanide inhibited the reaction catalyzed by CuZnSOD but accelerated that by $Cu^{2+}$ and $Fe^{3+}$. Oxidation of $DCFH_2$ by $H_2O_2$ in the presence of a cell lysate was also enhanced by bicarbonate and inhibited by cyanide. Confocal microscopy of $H_2O_2$-treated cells showed enhanced DCF fluorescence in the presence of bicarbonate and attenuated fluorescence for the cells pre-incubated with KCN. Moreover, DCF fluorescence was intensified in CuZnSOD-transfected HaCaT and RAW 264.7 cells. We propose that CuZnSOD is a potential intracellular catalyst for the $H_2O_2$-dependent oxidation of $DCFH_2$.

• Clean Technology
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• v.5 no.1
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• pp.20-29
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• 1999

In the treatment of Cu - and CN - contained wastewater by using Fenton oxidation-flocculation-precipitation, the optimal removal efficiencies of the cyanide and copper were investigated according to pH, reaction time, the molar ratio of cyanide and hydrogen peroxide and the mass ratio of ferrous sulfate and hydrogen peroxide for Fenton oxidation, and pH for hydroxide precipitation, respectively. As a result, the $CN^-$ removal efficiency in our experimental wastewater by the Fenton oxidation was 81.2%~99% at its optimal conditions of pH ranging from 3 to 5 and reaction time of 30 minutes. And the optimal dosage of hydrogen peroxide and ferrous sulfate was 214, $428mg/{\ell}$, 107, $161mg/{\ell}$, 214, $214mg/{\ell}$ and 520, $500mg/{\ell}$, respectively when the molar ratio of $Cu^{2+}$:CN is 2:1, 1:1, 1:2, 1:10, and was 900, $1050mg/{\ell}$ when the molar ratio of $Cu^+$: CN is 1:10. When the copper was precipitated by sodium hydroxide after Fenton oxidation, the copper removal efficiency in the wastewater at pH 7 was 98.92%, 98.52%, 92.46%, 90.6% and 95%, respectively.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1997.11a
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• pp.112-119
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• 1997

The modelling of carbon substances obtaining, for instance, carbon fibers which have high fire resistance, has been realized on the example of the polyacrylonitrile pyrolysis modelling. The pyrolysis is considered as a double step process when the formation of a liquid phase and the oxidation of substance are excluded. Three main reactions are considered: a) with the evolution of ammonia; b) with the evolution of hydrogen cyanide; c) with the evolution of hydrogen. Reactions b) and c) are sequential, and a) and b) are parallel. The problem is formulated as one-dimensional. The equations of energy, masses or concentrations, porosity and thermal conductivity are proposed. The mathematical model of the carbonization process is designed using tile kinetic characteristics of the above reactions and the thermodynamic parameters of reagents and products in these reactions. The equations received are calculated by Runge-Cutta method and by Adams method of the fourth order accuracy.

• Bulletin of the Korean Chemical Society
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• v.31 no.3
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• pp.582-587
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• 2010

A rhodium-catalyzed reductive cleavage reaction of carbon-cyano bonds is developed using hydrosilane as a mild reducing agent. A wide range of nitriles, including aryl, benzyl, and $\beta$-hydrogen containing alkyl cyanides are applicable to this decyanation reaction. The method is also applicable to organic synthesis, in which benzyl cyanide is used as a benzyl anion equivalent and a cyano group functions as a removable ortho-directing group.

• Journal of Environmental Science International
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• v.3 no.4
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• pp.439-443
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• 1994

In aqueous acid solution ${[Cr(CN)_6]}^{3-}$ aquates via a series of stepwise stereospecific reactions to give ${[Cr{(H_2O)}_6]}^{3+}$as the final product.Some of the intermediate cyanoaquo complexes in the sequence have been isolated.These complexes aquate by both acid independent and acid denpendent pathways, the latter involving protonation of the cyano ligands followed by aquation of the singly protonated species. The kinetic data for the aquation of {[CrCN{(H_2O)}_5]}^{2+}$ are consistent with the transition state structure ${[{(H_2O)}_4Cr(CN)-OH-Cr{(H_2O)}_5]}^{3+}$. Addition of $Cr^{2+}$ to solutions of cyanocobalt(III) complexes produces the metastable intermediate${[CrNC{(H_2O)}_5]}^{2+}$ This isomerizes to in a $Cr^{2+}$-catalyzed reaction which occurs by a ligand-bridged electron-change mechnism. From acid catalysis on these aquation reactions, it product HCN. Especially, $HSO_3$-ions do the role of catalyst in the formation of HCN from $CrCN^{3-}$

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.188-193
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• 1993

Superoxide dismutase (SOD) was purified from Pseudomonas polycolor to an electrophoretically homogeneous state and partially characterized. SOD was purified by ammonium sulfate fractionation, column chromatography on DEAE-Sephadex A-50, phenyl-Toyopearl 650 M, and gel filtration on Sephadex G-100. The molecular weight and subunit molecular weight of the purified enzyme were estimated to be 40, 000 and 20, 000, respectively. The purified enzyme remained stable at pH 9.0~11.0, $25^{\circ}C$ for 40 hr, but rapidly became inactive below 9.0. SOD was stable up to $45^{\circ}C$ at pH 9.0 with about 80% relative activity, but rapidly became inactive at temperature above that. The enzyme was insensitive to cyanide and fluoride, and sensitive to hydrogen peroxide and azide. The results suggest that the enzyme be an iron-containing SOD.

• Journal of the Korean institute of surface engineering
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• v.36 no.2
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• pp.184-193
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• 2003

Cyclic sweep voltametry was performed to investigate the electrochemical behavior of heavy metal ions and the organic additives in surface finishing process. And electrolysis using parallel plate electrode electrolyzer was carried out to simulate the treatment of real waste water. Results showed that more than 99 percent of Cu was recovered and selective recovery of Cu in mixed waste water was possible, but the possibility of economical recovery of Ni and Cr were very low due to the evolution of hydrogen gas. Electrochemical oxidation of cyanide and organic additives on anode showed very excellent removal rate. The complete removal of several hundred ppm of cynide was possible within several tens minutes and organics within 2 or 3 hours. Even in case of concentrate waste water, the complete removal of COD by using NaCl and air stirring seemed to be possible.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1361-1365
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• 2013

The smallest ketenimine and hydrogen cyanide N-methylide ($CH_2CNH$ and $CH_2NCH$) are provided from the argon/acetonitrile matrix samples exposed to radiation from laser ablation of transition-metals. New infrared bands are observed in addition to better determination of the vibrational characteristics for the previously reported bands, and the $^{13}C$ substituted isotopomers ($^{13}{CH_2}^{13}CNH$ and $^{13}CH_2N^{13}CH$) are also generated. Density functional frequency calculations and the D and $^{13}C$ isotopic shifts substantiate the vibrational assignments. $CH_2CNH$ is probably produced through single-step conversion of $CH_3CN$, whereas $CH_2NCH$ through two-step conversion via 2H-azirine. Inter-conversions between these two products evidently do not occur during photolysis and annealing.

• Archives of Pharmacal Research
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• v.15 no.4
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• pp.292-297
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• 1992

Coupling of naphthacylpyridinium bromide 2 [1-(2-naphthyl) ethanone-2-pyridinium bromide] with N-nitrosoacetarylamides afforded C-(2-naphthoyl)-N-arylmethanohydrazonoylpyridinium bromides 3A-C. Treatment of 3A-C with base afforded the corresponding tetrazines 6A-C. Cycloaddition of nitrilimines 5A-C to N-arylmaleimides, acrylonitrile, ethyl acrylate, acrylamide, fumaronitrile, $\alpha$-cyanocinnamonitriles, ethyl $\alpha$-cyano-p-nitrocinnamates and $\alpha$-cyano-p-nitrocinnamamide afforded the corresponding cycloadducts 7-14, respectively. The cycloadducts 11-14 undergo a facile thermal elimination of hydrogen cyanide to give the corresponding pyrazoles 18-21 respectively.