• 제목/요약/키워드: aromatic

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추출 방향성 물질을 함유한 마이크로 캡슐의 제조와 한지에의 적용 (Microcapsulations of Aromatic Essential Oils and Their Application to Korean Traditional Hanji(paper))

  • 조중연;신준섭;민춘기;류운형;이선호
    • 펄프종이기술
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    • 제33권2호
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    • pp.74-80
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    • 2001
  • This study was carried out to manufacture microcapsules from natural aromatic essential oils by polymeric emulsification and to evaluate their properties using microscopical and electro-chemical analysis techniques. It was shown that aromatic essential oils (yuja, lavender, and peppermint) could be microcapsulated and their emulsion has a good stability and storage characteristics.

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고응답성 유기계 전기변색성 소자의 제작과 특성 (Response-Improved Electrochromic Display Device Based on Organic Materials)

  • 권태선
    • 한국인쇄학회지
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    • 제12권1호
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    • pp.81.1-91
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    • 1994
  • Irradiation of aromatic diazonium salts resulted in an effcient elimination of nitrogen, yielding substitution products. This paper was not only studies about photolysis of aromatic diazonium with double salts but also coexistence of ion and radical when they was photolysis. Photolysis of aromatic diazonium was depend on excite wave length therefore photolysis products out put different absorption intensity such other. We also confirmed coexistence of ion and radical when they was accomplished photolysis. In case of BD, there are ion decomposition process about 90 percentage, decreased ion decomposition process the other side radical`s it was becomeing increased according to excite of short-wave length.

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Long Chain Dicationic Phase Transfer Catalysts in the Condensation Reactions of Aromatic Aldehydes in Water Under Ultrasonic Effect

  • Esen, Ilker;Yolacan, Cigdem;Aydogan, Feray
    • Bulletin of the Korean Chemical Society
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    • 제31권8호
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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.

Synthesis and Cyclization of Aromatic Polyhydroxyamides. 1. Model Compound Study

  • Kim, Hae-Young;Kim, Myung-Kyoon;Baik, Doo-Hyun;Simon Kantor
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 1998년도 가을 학술발표회논문집
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    • pp.37-40
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    • 1998
  • Aromatic polybenzoxazoles have been known since 1964 as a class of aromatic heterocyclic polymers that exhibit excellent thermal stability. Polyhydroxyamides (PHA), precursor polymers to PBO, can cyclize to farm stable heterocyclic polymers with the simultaneous release of small molecules, which can be expected to act as a fire quencher. (omitted)

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서울 지역의 PAHs(Polycyclic aromatic hydrocarbons)의 건식 침적량 특성의 연구 (A Study on the Characterization of Atmospheric Dry Deposition for Polycyclic aromatic hydrocarbons Measured in Seoul)

  • 이승묵;이지이;한영지;배수야;윤희정;정장표;이동수
    • 한국대기환경학회:학술대회논문집
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    • 한국대기환경학회 2000년도 춘계학술대회 논문집
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    • pp.94-96
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    • 2000
  • Polycyclic aromatic hydrocarbons(다환방향족 탄화수소류: 이하 PAHs)는 여러 가지 오염원에서 배출되어 환경계에서 이동하는 중요한 화합물질 그룹중의 하나이다. 대부분의 PAHs는 발암물질이라고 의심이 가는 물질로써 여러 가지 형태의 배열로 연결되어 있는 두개 혹은 그 이상의 방향족 고리로 구성되어 있다 PAHs의 대기에서의 침적은 가스상과 입자상 물질의 비나 눈에 의한 제거, 입자상 물질의 건식침적 및 가스상 물질의 대기-수체간 교환에 의하여 이루어진다. (중략)

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Association of a Common Reductase with Multiple Aromatic Terminal Dioxygenases in Sphingomonas yanoikuyae Strain B1

  • Mihyun Bae;Kim, Eungbin
    • Journal of Microbiology
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    • 제38권1호
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    • pp.40-43
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    • 2000
  • The aromatic dioxygenase system in Sphingomonas yanoikuyae strain Bl consists of three components, an oxygenase, a ferredoxin, and a reductase. The insertional knockout of the bphA4 gene encoding a reductase and subsequent complementation experiments showed that the reductase encoded by bphA4 in S. yanoikuyae strain Bl is associated with multiple dioxygenase components including that of toluate dioxygenase (XyIXY).

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Toxicological Effects of Polycyclic Aromatic Hydrocarbon Quinones Contaminated in Diesel Exhaust Particles

  • Kumagai, Yoshito;Taguchi, Keiko
    • Asian Journal of Atmospheric Environment
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    • 제1권1호
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    • pp.28-35
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    • 2007
  • Accumulated epidemiological and animal studies have suggested that prolonged exposure to ambient particulate matter (PM) is associated with an increased risk of cardiovascular disease and pulmonary dysfunction. While diesel exhaust particles (DEP) contain large variety of compounds, polycyclic aromatic hydrocarbons (PAHs) are a dominant component contaminated in DEP. This article reviews effects of two PAH quinones, 9,10-phenanthraquinone (9,10-PQ) and l,2-naphthoquinone (l,2-NQ), on vascular and respiratory systems.

Excimer Fluorescence Quenching of Poly (styrene-co-acrylic acid)-Eu Complex by Simple Hydrocarbons in Tetrahydrofuran Solutions

  • Park, Doo-Hee;Kim, Kang-Jin
    • Bulletin of the Korean Chemical Society
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    • 제7권1호
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    • pp.42-45
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    • 1986
  • Quenching of excimer fluorescence from polystyrene-acrylic acid copolymers containing $Eu^{3+}$ has been studied in tetrahydrofuran solution using simple aromatic hydrocarbons as quenchers under steady-state conditions. Aromatic hydrocarbons quenched collisionally the excimer fluorescence and their rate constants of quenching were determined. The magnitude of quenching constant is interpreted in terms of the cube root of the molar volume of quencher. Cycloalkanes were not effective in quenching the excimer fluorescence possibly due to different solubility characteristics from aromatic hydrocarbons.

Polymerization of Anisole Derivatives Containing Allyl or Chloromethyl Group Through Aromatic Electrophilic Substitution Reaction

  • 장지영;박필정;한만정
    • Bulletin of the Korean Chemical Society
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    • 제18권12호
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    • pp.1288-1291
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    • 1997
  • 4-Allylanisole was polymerized with AlCl3 as a catalyst. The polymerization was carried out in nitroethane at various temperatures with changing the ratio of the initiator to the monomer concentration. The weight averge molecular weights measured by gel permeation chromatography in chloroform with polystyrene standards were between 1,500 and 4,700. 1H NMR spectroscopy showed that the polymerization proceeded through a stepwise aromatic electrophilic substitution reaction along with a minor chain-reaction, resulting in a branched polymer. 4-Chloromethylanisole was also polymerized with AlCl3 in nitroethane through an aromatic electrophilic substitution reaction to give a high molecular weight polymer (Mw=88,000).

Catalytic Hydrogenation of Aromatic Nitro Compounds over Borohydride Exchange Resin Supported Pd (BER-Pd) Catalyst

  • Yoon, Nung-Min;Lee, Hyang-Won;Choi, Jae-Sung;Lee, Hyun-Ju
    • Bulletin of the Korean Chemical Society
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    • 제14권2호
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    • pp.281-283
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    • 1993
  • Aromatic nitro compounds are selectively hydrogenated to the corresponding amines in high yields at room temperature and atmospheric pressure using BER-Pd catalyst without affecting ketone, ether, ester, nitrile or chloro groups also present. Especially the nitro group in 4-nitrobenzyl alcohol, methyl 4-nitrobenzyl ether and N-N-dimethyl 4-nitrobenzylamine is selectively hydrogenated with this catalyst to give the corresponding amines without hydrogenolysis of benzylic groups. And aromatic nitro compound can be reduced selectively in the presence of aliphatic nitro compound.