• Korean Journal of Microbiology
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• v.55 no.1
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• pp.55-57
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• 2019

The Runella sp. ABRDSP2, capable of degrading mono-aromatic compounds such as toluene, was isolated from freshwater. The whole genome, consisting of a circular single chromosome and three plasmids, was composed of total 7,613,819 bp length with 44.4% G+C contents and 6,006 genes. The genome of strain ABRDSP2 contains many aromatic hydrocarbon degrading genes such as monooxygenase, ring-cleaving dioxygenase, and catechol 1,2-dioxygenase. The complete genome reveals versatile biodegradation capabilities of Runella sp. ABRDSP2.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2289-2292
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• 2010

Long chain dicationic ammonium salts were used successfully as phase transfer catalyst in the condensation reactions of aromatic aldehydes in water under ultrasonic irradiation for the first time. The quaternary salt having longer distance between the cation centers was more effective than the mono- and dicationic ones having short chain.

• Natural Product Sciences
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• v.24 no.2
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• pp.115-118
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• 2018

Herein, we reported the phytochemical investigation of whole thallus Sumatran lichen, Stereocaulon graminosum Schaer, and isolated a mono aromatic compound, ethyl haematommate (1). The structure of compound 1 have been established based on spectroscopic data and confirmed by single crystal X-ray structure analysis.

• Journal of the Korean Chemical Society
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• v.50 no.4
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• pp.281-290
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• 2006

The electronic structure and properties of the 1H-indene and mono-sila-1H-indene series have been investigated using basis set of 6-31G(d, p) and hybrid density functional theory. Basic measures of aromatic character derived from structure, molecular orbitals, a variety of magnetic criteria (magnetic isotropic and anisotropic susceptibilities) are considered. Energetic criteria suggest that In(Si7) enjoy conspicuous stabilization. However, by magnetic susceptibility isotropic this system are among the least aromatic of the family: Within their isomer series, In(Si4) is the most aromatic using this criteria. Natural bond orbital (NBO) analysis method was performed for the investigation of the relative stability and the nature of the 8-9 bonds in 1H-indene and mono-sila-1H-indene compounds. The results explained that how the p character of natural atomic hybrid orbital on X8 and X9 (central bond) is increased by the substitution of the C8 and C9 by Si. Actually, the results suggested that in these compounds, the X8-X9 bond lengths are closely controlled by the p character of these hybrid orbitals and also by the nature of C-Si bonds. The magnitude of the molecular stabilization energy associated to delocalization from X8-X9 and to * X8-X9 bond orbital were also quantitatively determined. Molecular orbital (MO) analysis further reveal that all structure has three delocalized MOs and two delocalized MOs and therefore exhibit the aromaticity.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.1
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• pp.88-95
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• 1998

The Electron/Hole Pair is generated when the Activation Energy produces by Ultraviolet Ray illumination to the Semiconductor. And $OH^-$ ion produces by Water Photo-Cleavage reacts with Positive Hole. As a result, OH Radical acting as strong oxidant is generated and then Photocatalytic Oxidation Reaction occurs. The Photocatalytic Oxidation can oxidize the chlorophenol to Chloride and Carbon Dioxide easier, safer and shorter than conventional Water Treatment Process With the same degree of chlorination, the $Cl^-$ ion at para (C4) position is most easily replaced by the OH radical. And then, the blocking effect of $OH^-$ ion between the $Cl^-$ ions and $Cl^-$ ions at symmetrical location is easily replaced by the OH radical. For mono-, di-, tri-chlorophenols, there is no obvious difference in decomposition rate, decomposition efficiency and completeness of the decomposition reaction except for 2,3-dichloropheno, 2,4,5-, 2,3,4-trichlorophenol. The decomposition efficiency is higher than 75% and completeness of the decomposition reaction is higher than 70%. Therefore, continuous flow photocatalytic reactor is promising process to remove the chlorinated aromatic compounds which is more toxic than non-chlorinated aromatic compound.

• Journal of the Korean Chemical Society
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• v.22 no.5
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• pp.326-333
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• 1978

m-Phenylenedihydrazine(MPDH) was prepared via tetrazonium salt: m-Phenylenediamine was tetrazotized with sodium nitrite at $-10∼-5^{\circ}C$ in concentrated hydrochloric acid medium, reused tetrazonium salt was reduced with stannous chloride and MPDH was separated as dihydrochloride which was recrystallized from alcohol. The free base of MPDH being unstable it could hardly be obtained in the air. $MPDH{\cdot}2HCl$ did not show sharp melting point but decomposed at $185^{\circ}C$. MPDH, like aromatic monohydrazines, condensed with mono-and dicarbonyl compounds giving dihydrazones or cyclic compounds. The structures of condensation products obtained from the reaction of MPDH with carbonyl compounds are determined.

• Mass Spectrometry Letters
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• v.2 no.2
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• pp.41-44
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• 2011

Molecular compositions of two types of heavy oil were studied using positive atmospheric pressure photoionization (APPI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Vacuum gas oil (VGO) was generated from vacuum distillation of atmospheric residual oil (AR), and slurry oil (SLO) was generated from catalytic cracking of AR. These heavy oils have similar boiling point ranges in the range of 210-$650^{\circ}C$, but they showed different mass ranges and double-bond equivalent (DBE) distributions. Using DBE and carbon number distributions, aromatic ring distributions, and the extent of alkyl side chains were estimated. In addition to the main aromatic hydrocarbon compounds, those containing sulfur, nitrogen, and oxygen heteroatoms were identified using simple sample preparation and ultra-high mass resolution FT-ICR MS analysis. VGO is primarily composed of mono- and di-aromatic hydrocarbons as well as sulfur-containing hydrocarbons, whereas SLO contained mainly polyaromatic hydrocarbons and sulfur-containing hydrocarbons. Both heavy oils contain polyaromatic nitrogen components. SLO inludes shorter aromatic alkyl side chains than VGO. This study demonstrates that APPI FT-ICR MS is useful for molecular composition characterization of petroleum heavy oils obtained from different refining processes.

• Journal of Environmental Health Sciences
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• v.37 no.6
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• pp.474-481
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• 2011

This study investigated urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) in the urine of smokers and non-smokers by liquid chromatography triple quordrupole tandem mass spectroscopy (LC/MS/MS). Compounds analyzed for urinary biomarkers of PAHs were five mono-hydroxylated PAHs metabolites; 1-naphthol, 2-naphthol, 1-hydroxypyrene(1-OHP), 3-phenanthrol, 2-fluorenol. Urine samples were pretreated by enzymatic hydrolysis and solid phase extraction method. Smokers were composed of 17 men and five women; non-smokers 17 men and 16 women. Smoking increased urinary concentrations of five PAHs metabolites significantly higher than those of nonsmokers. Statistically significant correlations among the five PAHs metabolites were shown. The results suggest that LC/MS/MS technology should be useful in the environmental health discipline.

• Analytical Science and Technology
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• v.10 no.2
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• pp.139-145
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• 1997

Alkylbenzenes used as synthetic lubricant base oils have been analyzed to find the quantity of mono- and di-substituted alkyl aromatic hydrocarbon compositions and the number of carbon atoms in alkyl chains by $^{13}C$-NMR, near-infrared, and UV-Vis spectroscopy. Also, linear long chain alkylated benzene in the engine lubricants was analyzed quantitatively by infrared spectroscopy.

• Journal of Nutrition and Health
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• v.15 no.1
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• pp.22-29
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• 1982

As sugar and amino acid were added to the ascorbic acid solution the content of ascorbic acid was quantitatively determined by 2, 4-dinitrophenyl hydrazine method. The residual ascorbic acid was shown to increase slightly when sorbose, rhamnose or mannose was added to the ascorbic acid solution whereas residual ascorbic acid was shown to decrease in time to the addition of other sugars. The effects of amino acid to the ascorbic acid solution were found that monoamino-mono, or dicarboxylic acids and aromatic amino acids increased the residual ascorbic acidity whereas diamino-monocarboxylic acids and sulfur containing amino acids decreased the residual ascorbic acidity.