• 미생물학회지
• /
• 제55권1호
• /
• pp.55-57
• /
• 2019

페놀과 같은 단환성 화합물을 분해하는 미생물인 Runella sp. ABRDSP2 균주는 담수로부터 분리되었다. 원형으로 완성된 하나의 chromosome과 3개의 plasmid로 구성된 유전체는 GC 함량이 44.4%인 총 7,613,819 bp의 크기를 나타내며 6,006개의 유전자를 인코딩하고 있다. ABRDSP2 균주는 monooxygenase, ring-cleaving dioxygenase 및 catechol 1,2-dioxygenase 등의 다수의 방향성 탄화수소를 분해하는 유전자를 함유하고 있다. 이런 전장 유전체는 Runella sp. ABRDSP2 균주가 다양한 생분해능력이 있음을 나타낸다.

• Bulletin of the Korean Chemical Society
• /
• 제31권8호
• /
• pp.2289-2292
• /
• 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
• /
• 제24권2호
• /
• pp.115-118
• /
• 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.

• 대한화학회지
• /
• 제50권4호
• /
• pp.281-290
• /
• 2006

Hybrid DFT 계산 방법을 이용하여 1H-Indene과 Mono-sila-1H-indene 분자의 구조와 특성에 관한 이론적 연구를 수행하였다. 이 분자들의 방향족성 특성 연구를 위하여 MO, 비등방성 자기 민감도 등을 계산하였다. 1H-Indene과 Mono-sila-1H-indene 분자들에 대한 X8-X9 결합의 상대적인 안정도와 특성을 이해하기 위하여 NBO 계산을 수행하였다. 그 결과, 8, 9 위치의 Si 원자들이 C 원자들로 치환되었을 때, p orbital의 기여도가 증가하였다. 이러한 결과는 X8-X9 결합 길이는 하이브리드 오비탈의 p 오비탈 기여도에 크게 영향받는 사실을 보여준다. NBO계산을 통하여 X8-X9로부터 *X8-X9 결합 오비탈로의 비편재화에 기인하는 정량적인 에너지 안정화 세기를 결정하였다. MO 분석 결과 연구 대상 분자들의 방향족성은 3개의 비편재화된 pMO와 2개의 비편재화된 sMO에 의해서 주로 영향 받는다는 사실을 알 수 있었다.

• 상하수도학회지
• /
• 제12권1호
• /
• pp.88-95
• /
• 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.

• 대한화학회지
• /
• 제22권5호
• /
• pp.326-333
• /
• 1978

Tetrazonium 염을 거쳐서 m-phenylenedihydrazine (MPDH)을 합성할 수 있었다. 즉, m-phenylenediamine을 진한 염산의 매질 속에서 $-10∼-5^{\circ}C$로 유지하고아질산나트륨으로 테트라 아조화한 다음, 이때 생긴 tetrazonium 염을 염화주석(II)으로 환원시켜 MPDH를 염산염의 꼴로 얻어 알코올에서 재결정 할 수 있었다. MPDH의 유리염기는 불안정하기 때문에 공기 중에서는 안정한 상태로 얻기 어려우며, 그 염산염은 명확한 녹는 점을 가지지 않고 $185^{\circ}C$에서 분해하였다. MPDH도 방향족 monohydrazine의 경우 처럼 mono 또는 dicarbnyl 화합물과 쉽게 축합반응을 일으켜서 dihydrazone 또는 고리모양 화합물을 생성하였다. MPDH와 carbonyl 화합물과의 반응에서 얻은 여러가지 화합물의 구조를 결정하였다.

• Mass Spectrometry Letters
• /
• 제2권2호
• /
• pp.41-44
• /
• 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.

• 한국환경보건학회지
• /
• 제37권6호
• /
• pp.474-481
• /
• 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.

• 분석과학
• /
• 제10권2호
• /
• pp.139-145
• /
• 1997

합성 윤활기유로 사용되고 있는 알킬벤젠들 중에 단일, 그리고 이중치환된 알킬벤젠의 양과 알킬사슬에 존재하는 탄소원자의 수를 $^{13}C$-NMR, 근적외선 및 UV-Vis 분광법으로 분석하였다. 또한 엔진윤활유에 포함되어 있는 직선형 긴 사슬 알킬벤젠을 적외선분광법으로 분석하였다.

• Journal of Nutrition and Health
• /
• 제15권1호
• /
• pp.22-29
• /
• 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.