• Korean Chemical Engineering Research
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• v.49 no.5
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• pp.510-515
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• 2011

The pyrolytic reaction of 1,1-dichloroethylene($CH_2CCl_2$) has been conducted to investigate thermal decomposition of chlorocarbon and product formation pathways under hydrogen reaction environment. The reactions were studied in a isothermal tubular flow reactor at 1 atm total pressure in the temperature range $650{\sim}900^{\circ}C$ with reaction times of 0.3~2.0 sec. A constant feed molar ratio $CH_2CCl_2:H_2$ of 4:96 was maintained through the whole experiments. Complete decay(99%) of the parent reagent, $CH_2CCl_2$ was observed at temperature near $825^{\circ}C$ with 1 sec. reaction time. The important decay of $CH_2CCl_2$ under hydrogen reaction environment resulted from H atom cyclic chain reaction by abstraction and addition displacement. The highest concentration (28%) of $CH_2CHCl$ as the primary product was observed at temperature $700^{\circ}C$, where up to 46% decay of $CH_2CCl_2$ was occurred. The secondary product, $C_2H_4$ as main product was detected at temperature above $775^{\circ}C$. The one less chlorinated ethylene than parent increase with temperature rise subsequently. The HCl and dechlorinated hydrocarbons such as $C_2H_4$, $C_2H_6$, $CH_4$ and $C_2H_2$ were the main products observed at above $825^{\circ}C$. The important decay of $CH_2CCl_2$ resulted from H atom cyclic chain reaction by abstraction and addition displacement. The important pyrolytic reaction pathways to describe the features of reagent decay and intermediate product distributions, based upon thermochemical and kinetic principles, were suggested.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.77-80
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• 2007

As neurofilament proteins are major cytoskeletal components of neuron, abnormality of neurofilament is proposed in brain with neurodegenerative disorders such as Parkinson's disease (PD). Since oxidative stress might play a critical role in altering normal brain proteins, we investigated the oxidative modification of neurofilament-L (NF-L) induced by the reaction of cytochrome c with H2O2. When NF-L was incubated with cytochrome c and H2O2, the protein aggregation was increased in cytochrome c and H2O2 concentrationsdependent manner. Radical scavengers, azide, formate and N-acetyl cysteine, prevented the aggregation of NFL induced by the cytochrome c/H2O2 system. The formations of carbonyl group and dityrosine were obtained in cytochrome c/H2O2-mediated NF-L aggregates. Iron specific chelator, desferoxamine, prevented the cytochrome c/H2O2 system-mediated NF-L aggregation. These results suggest that the cytochrome c/H2O2 system may be related to abnormal aggregation of NF-L which may be involved in the pathogenesis of PD and related disorders.

• Industry Promotion Research
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• v.3 no.2
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• pp.1-8
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• 2018

In this study, the reaction mechanism of ethane and the reaction rate equation suitable for hydrocarbon reforming were studied. Through the reaction mechanism analysis, it was confirmed that three reactions (CO2 + H2, C2H6 + H2, C2H6 + H2O) proceed during the reforming reaction of ethane, each reaction rate (CO2+H2($r=3.42{\times}10-5molgcat.-1\;s-1$), C2H6+H2($r=3.18{\times}10-5mol\;gcat.-1s-1$), C2H6+H2O($r=1.84{\times}10-5mol\;gcat.-1s-1$)) was determined. It was confirmed that the C2H6 + H2O reaction was a rate determining step (RDS). And the reaction equation of this reaction can be expressed as r = kS * (KAKBPC2H6PH2O) / (1 + KAPC2H6 + KBPH2O) (KA = 2.052, KB = 6.384, $kS=0.189{\times}10-2$) through the Langmuir-Hinshelwood model. The obtained equation was compared with the derived power rate law without regard to the reaction mechanism and the power rate law was relatively similar fitting in the narrow concentration change region (about 2.5-4% of ethane, about 60-75% of water) It was confirmed that the LH model reaction equation based on the reaction mechanism shows a similar value to the experimental value in the wide concentration change region.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.832-836
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• 2003

To extend the knowledge of triple bonding between group 6 transition metal and heavier group 14 elements, the structural and bonding aspects of ($η^5-C_5H_5$)$(CO)_2$M≡ER (M = Cr, Mo, W; E = Si, Ge, Sn, Pb) are investigated by hybrid density functional calculations at the B3PW91 level. Substituent effects are also investigated with R = H, Me, $SiH_3$, Ph, $C_6H_3-2,6-Ph_2$, $C_6H_3-2,6-(C_6H_2-2,4,6-Me_3)_2$, and $C_6H_3-2,6-(C_6H_2-2,4,6- iPr_3)_2$.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3745-3748
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• 2010

Pd(II) p-tolylamide Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)(NH($C_6H_4Me$-p)) (1) was metathetically prepared by the reaction of Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)Cl with NaNH($C_6H_4Me$-p). Treatment of 1 with carbon dioxide affords the palladium(II) carbamate Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)(OC(O)NH($C_6H_4Me$-p)) (2), quantitatively. Complex 2 reacts with HX (X = Cl, OTf) to give Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)X, $NH_2$(p-Tol) and $CO_2$. Reaction of the palladium(II) carbamate with MeI produced Pd(2,6-$(Ph_2PCH_2)_2C_6H_3$)I along with generation of methyl N-tolylcarbamate MeOC(O)NH($C_6H_4Me$-p), exclusively.

• Bulletin of the Korean Chemical Society
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• v.23 no.7
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• pp.953-956
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• 2002

Excess molar volumes (Vm E ) of binary liquid mixtures: xC6H5CH3 + (1-x1)CH3CN or + (1-x1)C6H5NO2, or + (1-x1)C2H5NO2 have been determined as a function of mole fraction of C6H5CH3 (x) at a temperature of 303.15 K over a entire range of composition. The densities of the binary liquid mixtures were determined by pycnometrically. The VmE values of the mixtures have been found to be negative over the whole composition in order of C6H5CH3 + C6H5NO2, < C6H5CH3 + CH3CN, and < C6H5CH3 + C2H5NO2. The negative magnitude of VmE suggests the presence of intermolecular interaction in the three binary liquid mixtures.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.662-671
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• 1993

New Ni(II) and Pd(II) complexes of isonitrosomethylacetoacetate imine derivatives, Ni(IMAA-NH)(IMAA-NH'), Ni(IMAA-NH)(IMAA-NR), $Pd(IMAA-NH)_2\;and Pd(IMAA-NR)_2(R=CH_3,\;C_2H_5,\;n-C_3H_7,\;n-C_4H_9,\;or\;CH_2C_6H_5)$, where H-IMAA-NH and H-IMAA-NR represent isonitrosomethylacetoacetate imine and N-alkylisonitrosomethylacetoacetate imine derivative, respectively, have been prepared and the structures of the complexes have been studied by elemental analyses, electronic, infrared, and $^1H-\;and\;^{13}C-NMR$ spectroscopies.

• BMB Reports
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• v.39 no.4
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• pp.452-456
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• 2006

To elaborate the peroxidase activity of cytochrome c in the generation of free radicals from $H_2O_2$, the mechanism of DNA cleavage mediated by the cytochrome c/$H_2O_2$ system was investigated. When plasmid DNA was incubated with cytochrome c and $H_2O_2$, the cleavage of DNA was proportional to the cytochrome c and $H_2O_2$ concentrations. Radical scavengers, such as azide, mannitol, and ethanol, significantly inhibited the cytochrome c/$H_2O_2$ system-mediated DNA cleavage. These results indicated that free radicals might participate in the DNA cleavage by the cytochrome c and $H_2O_2$ system. Incubation of cytochrome c with $H_2O_2$ resulted in a time-dependent release of iron ions from the cytochrome c molecule. During the incubation of deoxyribose with cytochrome c and $H_2O_2$, the damage to deoxyribose increased in a time-dependent manner, suggesting that the released iron ions may participate in a Fenton-like reaction to produce $\cdot$OH radicals that may cause the DNA cleavage. Evidence that the iron-specific chelator, desferoxamine (DFX), prevented the DNA cleavage induced by the cytochrome c/$H_2O_2$ system supports this mechanism. Thus we suggest that DNA cleavage is mediated via the generation of $\cdot$OH by a combination of the peroxidase reaction of cytochrome c and the Fenton-like reaction of free iron ions released from oxidatively damaged cytochrome c in the cytochrome c/$H_2O_2$ system.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.830-834
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• 2006

Lipid peroxidation induced by the reaction of cytochrome c with $H_2O_2$ was investigated. When linoleic acid micelles or phosphatidyl choline liposomes were incubated with cytochrome c and $H_2O_2$, lipid peroxidation was increased in cytochrome c and $H_2O_2$ concentrations-dependent manner. Radical scavengers, azide, formate and ethanol prevented lipid peroxidation induced by the cytochrome c/$H_2O_2$ system. Iron specific chelator, desferoxamine also prevented the cytochrome c/$H_2O_2$ system-mediated lipid peroxidation. These results suggest that lipid peroxidation may be induced by the cytochrome c/$H_2O_2$ system via the generation of free radicals. Carnosine, homocarnosine and anserine are present in the muscle and brain of many animals and human. Previous studies show that these compounds have an antioxidant function. In the present study, carnosine, homocarnosine and anserine significantly prevented the cytochrome c/$H_2O_2$ system-mediated lipid peroxidation. Carnosine and related compounds also inhibited the free radical-generating activity of cytochrome c. The results suggest that carnosine, homocarnosine and anserine may prevent lipid peroxidation induced by the cytochrome c/$H_2O_2$ system through a free radical scavenging.

• Journal of the Korean Chemical Society
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• v.9 no.4
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• pp.161-168
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• 1965

The effect of solvents on the stabilities of the $C_6H_6{\cdot}I_2$ complex and the $C_6H_6{\cdot}ICl$ complex has been investigated through ultraviolet spectrophotometric measurements. The equilibrium constants obtained at room temperature for the formation of $C_6H_6{\cdot}I_2$ complex are 0.090, 0.216 and 0.328$ lmole^{-1}$ in chloroform, cyclohexane and n-hexane, respectively. The corresponding equilibrium constants at room temperature for $C_6H_6{\cdot}ICl$ complex are 0.125, 0.676 and 0.689 $lmole^{-1}.$ These results indicate that the stabilities of the two complexes increase with decreasing dielectric constants of the solvents used, the increase in stability being more rapid in the $C_6H_6{\cdot}ICl$ complex than in the $C_6H_6{\cdot}I_2$ complex. This may support the conclusion that the dative ionic structures, $C_6H_6^+{\cdots}I_2^-$ and/or ($C_6H_6I)^+{\cdots}Cl^-,$ play important roles on the reasonance stabilization of both the $C_6H_6{\cdot}I_2$ complex and the $C_6H_6{\cdot}ICl$ complex, the roles being more important in the latter complex than in the former complex.