• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1203-1205
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• 2006

During the synthesis of 4-fluorobenzaldehyde via the SNAr reaction of 4-nitrobenzaldehyde with TBAF, it was found that an equivalent amount of TBAF could oxidize benzaldehyde to benzoic acid. The reaction of 4-nitrobenzaldehyde with tetrabutylammonium fluoride (TBAF) gave 4-nitrobenzoic acid in high yield. Depending on the reaction conditions, other aromatic aldehydes produced acids with fewer amounts of alcohols. However, this type of oxidation has limited practical applications. Nevertheless, the mechanism is quite different from the Cannizzaro reaction because the amounts of the acid salt and alcohol formed were different.

• Journal of environmental and Sanitary engineering
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• v.12 no.2
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• pp.51-57
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• 1997

This work carried out the removal of aniline by wet oxidation in aqueous solutions like a industrial wastewater using Ozone, UV, and Ozone-UV . The main features of this experiment are as follows: the aniline was decomposed by OH and HO$_{2}$ radicals which produced from the reaction of water with UV and Ozone, when the Ozorie and Ozone-UV used the aniline was decomposed completely. The decomposition of aniline was very fast reaction and the reaction times were within 10min. and 20min. in case of for Ozone Ozone-UV respectively. Assumed simplified reaction mechanism from the aniline oxidation model, and the we are calculated the theoretical reaction rate constants by computer simulation, and then compared with experimental data. We suggest that this simulation program is applicable to estimate of the aniline decaying concentration and removal efficiency of aniline - contaminated wastewater.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.360-362
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• 1988

The new oxidation method was presented to grow the oxide layer by thermal reaction of $NH_{3}$ and $O_{2}$. The growth rate increased according as increase of partial pressure of $NH_{3}$. Optical transparent of the grown film was 12% compared with 17% of thermal oxidation when the wave number was $1,100cm^{-1}$. The oxide layer with good quaility was obtained.

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.2023-2027
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• 2006

Dibenzyl sulfide was oxidized at the a-carbon to yield benzaldehyde in the presence of $Pd(NO_3)_2$. Oxygen itself could not oxidize the sulfide directly, instead the nitrato ligand of the palladium complex transferred oxygen to dibenzyl sulfide to form benzaldehyde. The X-ray crystal structure of the intermediate complex, cis-[$Pd(NO_3)_2${$S(CH_2C_6H_5)_2$}$_2$], revealed that the nitrato ligand was unidentate. Para-substituted dibenzyl sulfides I, $(YC_6H_4CH_2)_2S $wherein Y = $OCH_3$, $CH_3$, Cl, CN, or $NO_2$, were synthesized and reacted with palladium nitrate, and those with electron-donating substituents (Y = $OCH_3$ and $CH_3$) were good substrates for the oxidation reaction with palladium nitrate. Thus, the reaction mechanism of the oxygen transfer was proposed to include nucleophilic benzylic carbon.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.532-537
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• 2009

The tropospheric ozone production mechanism for the gas phase additive oxidation reaction of hydroxyl radical (OH) with isoprene (2-methyl-1,3-butadiene) has been studied using cavity ring-down spectroscopy (CRDS) at total pressure of 50 Torr and 298 K. The applicability of CRDS was confirmed by monitoring the shorter (~4%) ringdown time in the presence of hydroxyl radical than the ring-down time without the photolysis of hydrogen peroxide. The reaction rate constant, $(9.8{\pm}0.1){\times}10^{-11}molecule^{-1}cm^3s^{-1}$, for the addition of OH to isoprene is in good agreement with previous studies. In the presence of $O_2$ and NO, hydroxyl radical cycling has been monitored and the simulation using the recommended elementary reaction rate constants as the basis to OH cycling curve gives reasonable fit to the data.

• Journal of the Korean Chemical Society
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• v.57 no.2
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• pp.210-215
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• 2013

Kinetics of oxidation of indole by peroxomonosulphate (PMS) in aqueous acetonitrile medium has been investigated. The reaction follows a total second order, first order each with respect to [Indole] and [PMS]. The rate of the reaction was not affected by added [$H^+$]. Variation of ionic strength (${\mu}$) had no influence on the rate. Increase of percentage of acetonitrile decreased the rate. Absen ce of any polymerization indicated a nonradical pathway. Activation and thermodynamic parameters have bee n computed. A suitable kinetic scheme based on these observations is proposed. The reactivity of PMS towards Indole was found to be higher than that with peroxodisulphate.

• Proceedings of the Membrane Society of Korea Conference
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• 1999.07a
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• pp.55-58
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• 1999

Nafion supported catalytic membranes were found to be active, stable and selective in th partial oxidation of propane to oxygenates with H2O2 under mild condition. Addition of Fe2+ in liquid phase enhances the reaction rate. Reaction proceeds according to a radical mechanism based on th electrophilic activation of propane on superacid sites and subsequent reaction of the activated paraffin with OH radicals. The use of a catalytic membrane, which allow separation of the intermediate products from the liquid phase containing the oxidant, was found to be effective to perform selective partial oxidation of propane with high yields to oxygenated products.

• Bulletin of the Korean Chemical Society
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• v.9 no.2
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• pp.81-84
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• 1988

The CO oxidation was performed on $H_2$-reduced NiO-${\alpha}-Fe_2O_3$ in the temperature range 150-$250^{\circ}C$. The kinetic study and the conductivity measurements indicate the oxidation reaction follows Langmuir-Rideal type process that is uncommon in heterogeneous catalyst$^1$. No active site is found on the catalyst surface for CO adsorption, but an oxygen vacancy adsorbs an oxygen, and this step is rate initiation. The partial orders are half for $O_2$ and first for CO, respectively. Apparent activation energy for over-all reaction is 9.05 kcal/mol.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.83-93
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• 1982

In this work, lipid oxidation and the kinetics of the oxidation reaction in fried file-fish meat were investigated when sun-dried file-fish was stored under the conditions of various water activities and temperature, 35, 45, 55 and $35/55^{\circ}C$. The storage stability and the development of browning by oxidative rancidity were also discussed. Monolayer coverage value of water content in dried file-fish was $8.03\%$ at $0.21\;a_w$Lipid oxidation at $35^{\circ}C$ was developed with increasing water activity but at $45^{\circ}C$and $55^{\circ}C$ it was rapidly progressed without clear differences between water activities except $0.44\;a_w$. The rate of reaction was more sensitive to storage temperature than to water activity. Browning in methanol-chloroform fraction was developed linearly by the progress of lipid oxidation which suggested that lipid oxidation was greatly influential to the development of browning in dried fish meat. In kinetical analysis the oxidation followed a zero order reaction mechanism as a function of carbonyl value. The activation energies obtained from the Arrhenius plot ranged 9.0 to 10.8 Kcal/mol and $Q_10$ values, 1.6-1.7. Shelf-lives at the storage of 35,45 and $55^{\circ}C$ ranged 58 days to 8 days. And in the fluctuating temperature storage at $35/55^{\circ}C$, shelf-lives were 17, 16, 15 and 13 days at 0.44, 0.52, 0.65 and $0.75\;a_w$, respectively. The shelf-lives for assessed from the accelerated shelf-life test were 125, 123, 120 and 106 days at 0.44, 0.52, 0.65 and $0.75\;a_w$, respectively, in the case of storage at $25^{\circ}C$.

• Journal of Powder Materials
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• v.19 no.6
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• pp.435-441
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• 2012

A new manufacturing process of Fe-Cr-Al powder porous metal was attempted. First, ultra-fine fecralloy powders were produced by using the submerged electric wire explosion process. Evenly distributed colloid (0.05~0.5% powders) was dispersed on PU (Polyurethane) foam through the electrospray process. And then degreasing and sintering processes were conduced. In order to examine the effect of sintering temperature in process, pre-samples were sintered for two hours at temperatures of $1350^{\circ}C$, $1400^{\circ}C$, $1450^{\circ}C$, and $1500^{\circ}C$, respectively, in $H_2$ atmospheres. A 24-hour TGA (thermo gravimetric analysis) test was conducted at $1000^{\circ}C$ in a 79% $N_2$+21% $O_2$ to investigate the high temperature oxidation behavior of powder porous metal. The results of the high temperature oxidation tests showed that oxidation resistance increased with increasing sintering temperature (2.57% oxidation weight gain at $1500^{\circ}C$ sintered specimen). The high temperature oxidation mechanism of newly manufactured Fe-Cr-Al powder porous metal was also discussed.