• Title/Summary/Keyword: aromatics

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Reusable and Efficient Polystryrene-supported Acidic Ionic Liquid Catalyst for Mononitration of Aromatic Compounds

  • Li, Li Xia;Ling, Qi Long;Liu, Zu Liang;Xing, Xiao Dong;Zhu, Xiao Qin;Meng, Xiao
    • Bulletin of the Korean Chemical Society
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    • v.33 no.10
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    • pp.3373-3377
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    • 2012
  • A series of polystyrene-supported 1-(propyl-3-sulfonate)-3-methyl-imidazolium hydrosulfate acidic ionic liquid (PS-$[SO_3H-PMIM][HSO_4]$) catalysts were prepared and tested for mononitration of simple aromatics compounds with nitric acid. It was found that the reactivity of the catalysts increased with increasing $[SO_3H-PMIM][HSO_4]$ content. The para-selectivity was not only related to the $[SO_3H-PMIM][HSO_4]$ content but also the substituent groups in aromatics. A reaction mechanism of nitration over this new catalyst was proposed. The catalytic activity of this catalyst decreased slightly after fifth runs in the synthesis of nitrotoluene.

A review of Spice Phenomenon Therapy (향신(香身)요법에 관한 문헌 고찰)

  • Lee, Seung-Ho;Park, Pil-Sang;Kwon, Dong-Yeul
    • Herbal Formula Science
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    • v.18 no.2
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    • pp.15-23
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    • 2010
  • The spice phenomenon therapy is to adhibit aromatic herbs or materials to the human body or clothing, for the purpose of preventing and treating diseases. Mankind found the fire, and found that some plants and trees give off smoke when they are burning. Then, they found that some of aromatic substances had certain actions after being absorbed through the respiratory organ, which was the beginning of the spice phenomenon therapy. The spice phenomenon therapy is effective to relieve the exterior syndrome, to eliminate dampness, to regulate Qi flow, and to induce resuscitation. It has two actions. One is that the aromas that permeated the body, refreshes the mind, stimulates the appetite, strengthens the spleen and the stomach, and makes a relaxing sleep. The other is that the aromatic substances, absorbed into the human body, have pharmacological actions. The volatile aromatic substances have various pharmacological actions such as stimulating cranial nerves, dilating cardiac blood vessels, promoting gastric secretion, relaxing and sleep-inducing. It has been proved that the spice phenomenon therapy is anti-inflammatory and anti-microbial and is effective to dilate cerebral blood vessels and to ease the pain. It is expected to be studied more aggressively.

A Study on Relationship between Fuel Characteristics and Combustion Characteristics of Reformed Diesel Fuels by Ultrasonic Energy Irradiation (II) - Relationship between Chemical Structure and Cetane Number - (초음파 개질 경유의 연료특성과 연소특성의 상관관계에 관한 연구 (II) -화학구조와 세탄가의 상관성-)

  • 이병오;류정인
    • Transactions of the Korean Society of Automotive Engineers
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    • v.11 no.1
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    • pp.64-71
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    • 2003
  • In order to analyze the effect of the chemical structure and the cetane number of reformed diesel fuels by ultrasonic energy irradiation, proton nuclear magnetic resonance spectrometer$(^1H-NMR)$ was used. From the study, following conclusive remarks can be made. 1) Branch Index(BI), aromatics percentages, and alpha methyl radical$(H_{\alpha})$ of the reformed diesel fuels by ultrasonic energy irradiation decreased more than the conventional ones. 2) All the cetane numbers which were calculated from carbon type structure and hydrogen type distribution of the reformed diesel fuels increased more than the conventional ones. 3) It is more reasonable to predict cetane number equation from carbon type structure than from hydrogen type distribution. 4) BI, aromatics percentages, and $H_{\alpha}$ on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation are inversely proportional to cetane number fur these fuels.

Structural Analysis of Petroleum Fractions by Near-Infrared and $^{13}C$-NMR Spectroscopy (근적외선과 $^{13}C$-핵자기 공명 분광학에 의한 석유유분 구조분석)

  • Choi, Ju-Hwan;Kim, Hai-Dong;Choi, Young-Sang
    • Analytical Science and Technology
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    • v.9 no.2
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    • pp.168-178
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    • 1996
  • Molecular structures of petroleum fractions(diesel fuel, bunker-C oil, lubricant base stocks) have been analyzed and compared in terms of the compositions (aromatics, naphtherucs, paraffinics), aromatics(benzene-nuclear and bonded alkyl groups), C2(methylene) carbon atoms % $C_{\alpha}$ and $C_{\beta}$ carbon stom % in alkyl groups and paraffins(branched and normal) by near-infrared and $^{13}C$-NMR spectroscopy.

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A Study on Treatment of Livestock wastewater using Fenton Oxidation and Zeolite Adsorption Process (Fenton 산화공정과 Zeolite 흡착공정을 연계한 축산폐수처리에 관한 연구)

  • Cho, Chang-Woo;Kim, Youn-Jeong;Chung, Paul-Gene
    • Journal of Korean Society on Water Environment
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    • v.21 no.5
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    • pp.505-510
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    • 2005
  • The objective of this study was to remove non-biodegradable matters and ammonia ion in livestock wastewater using Fenton oxidation and Zeolite adsorption process. After coagulation process as 1st treatment, non-biodegradable matters remained after 1st treatment were removed by using OH radical produced in Fenton oxidation process. Zeolite as cation adsoption process was used to remove ammonia ion in 2nd treatment water. As a result of treatment using these processes, NBDCOD removal efficiency was over 90% and ammonia ion was almost removed. Most aromatics or polynuclear aromatics like benzene, phenol and scatol in livestock wastewater wasn't detected after Fenton oxidation process.

Roles of the meta- and the ortho-Cleavage Pathways for the Efficient Utilization of Aromatic Hydrocarbons by Sphingomonas yanoikuyae Bl

  • 송정민;김영민;Gerben J. Zylstra;김응빈
    • Korean Journal of Microbiology
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    • v.38 no.4
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    • pp.245-245
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    • 2002
  • Catabolic pathways for the degradation of various aromatics by Sphingomonas yanoikuyae Bl are intertwined, joining at the level of substituted benzoates, which are further degraded vita ring cleavage reactions. The mutant strain EK497, which was constructed by deleting a large DNA region containing most of the genes for biphenyl, naphthalene, m-xylene, and m-toluate degradation, was unable to grow on all of the aromatics tested except for benzoate as the sole source of carbon and energy.S. yanoikuyae EK497 was found to possess only catechol ortho-ring cleavage activity due to deletion of the genes for the meta-cleavage pathway. Wild-type S. yanoikuyae Bl grown on benzoate has both catechol orthoand meta-cleavage activity. However, m-xylene and m-toluate, which are metabolized through methylbenzoate, and biphenyl, which is metabolized through benzoate, induce only the meta-cleavage pathway, suggesting the presence of a substrate-dependent induction mechanism.

Atomization Characteristics for Various Injection Nozzle Type and Property Changes (분사노즐 형상에 따른 유화연료의 분무 미립화 및 물성)

  • Kim, Yong-Guk;Ryu, Jeong-In
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.4
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    • pp.62-67
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    • 2010
  • The objective of this experimental study is to verify atomization characteristics of emulsified fuel. The emulsified fuel made of adding the ultrasonic energy is analyzed with atomization characteristics and chemicophysics. As water contents within emulsified fuel and needle angle increase, SMD, viscosity and surface tension were analyzed. By measuring the distribution percentage of hydrogen volume by $^1H$-NMR spectrum, the proportion of aromatics and paraffins is analyzed and compared each other. The results of study is as follows. First, as water contents within emulsified fuel and needle angle of nozzle increases, SMD increases. Second, for the distribution percentage of hydrogen volume, the distribution percentage of aromatics is about 10% and the rest portion is paraffins.