• Title/Summary/Keyword: Heterocyclic

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Liquid Membrane Permeation of Nitrogen Heterocyclic Compounds Contained in Model Coal Tar Fraction

  • Kim, Su-Jin;Kang, Ho-Cheol;Kim, Yong-Shik;Jeong, Hwa-Jin
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1143-1148
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    • 2010
  • We investigated the separation of nitrogen heterocyclic compound (NHC) contained in a model coal tar fraction comprising four kinds of NHC [indole (In), quinoline (Q), iso-quinoline (iQ), quinaldine (Qu)], three kinds of bicyclic aromatic compound (BAC) [1-methylnaphthalene (1MN), 2-methylnaphthalene (2MN), dimethylnaphthalene (DMN) mixture with ten structural isomers (DMNs; regarded as one component)], biphenyl (Bp) and phenyl ether (Pe) by liquid membrane permeation (LMP). A batch-stirred tank was used as the permeation unit. An aqueous solution of saponin and n-hexane were used as the liquid membrane and the outer oil phase, respectively. Yield and selectivity of individual NHC was much larger than that of BAC, Bp and Pe. Increasing the initial mass fraction of the saponin to the membrane solution ($C_{sap,0}$) and the initial volume fraction of O/W emulsion to total liquid in a stirred tank (${\phi}_{OW,0}$) resulted in deteriorating the yield of individual NHC, but increasing the stirring speed (N) resulted in improving the yield of each NHC. With increasing $C_{sap,0}$, the selectivity of each NHC based on DMNs increased. Increasing ${\phi}_{OW,0}$ and N resulted in decreasing the selectivity of individual NHC based on DMNs. At an experimental condition fixed, the sequence of the yield and selectivity in reference to DMNs for each NHC was Q > Qu = iQ > In. Furthermore, we compared LPM method with methanol extraction method in view of the separation efficiency (yield, selectivity) of NHC.

Photoluminescent Properties of Eu(III) in the Composite Heterocyclic Ligands/Crown Ether Systems

  • Liu, Hong Guo;Jang, Ki-Wan;Feng, Xu Sheng;Kim, Chang-Dae;Yoo, Young-Jae;Lee, Yong-Ill
    • Bulletin of the Korean Chemical Society
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    • v.26 no.12
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    • pp.1969-1974
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    • 2005
  • Composite systems of $Eu(phen)_2Cl_3{(H_2O)}_2$, Eu(DN-bpy)$(phen)Cl_3{(H_2O)}_2$ and Eu(DB-bpy)$(phen)Cl_3{(H_2O)}_2$ (DNbpy: $4,4^\prime$-Dinonyl-$2,2^\prime$-dipyridyl; DB-bpy: $4,4^\prime$-Di-tert-butyl-$2,2^\prime$-dipyridyl) with crown ethers of Benzo-15-crown-5 (B15C5), Benzo-18-crown-6 (B18C6), 18-crown-6 (18C6), Dibenzo-18-crown-6 (DB18C6) and Dibenzo-24-crown-8 (DB24C8) were fabricated successfully and characterized by using photoluminescent spectroscopy and luminescent lifetime measurements. All composites formed show high luminescence mainly in red region. It was found that the heterocyclic ligands such as phen, DN-bpy and DB-bpy as well as the crown ethers have great influences on the photoluminescent properties of $Eu^{3+}$ ion. The environment around $Eu^{3+}$ ion in the composite systems changes greatly,presumably the variation of the first coordination sphere. The $Eu^{3+}$ ion occupies higher symmetrical environment and in more than one kind of symmetrical site in the composite systems studied in this work.

Desmutagenic Action of Sugar Degradation Products (당(糖) 분해생성물의 돌연변이원성 억제작용)

  • Kim, Seon-Bong;Kim, In-Soo;Yeum, Dong-Min;Park, Yeung-Ho
    • Korean Journal of Food Science and Technology
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    • v.20 no.1
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    • pp.119-124
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    • 1988
  • The desmutagenic effects of ${\alpha}$-hydroxycarbonyl compounds, such as glyceraldehyde, glycolaldehyde, dihydroxyacetone, furfural, 5-hydroxymethylfurfural, maltol, acetol and acetoin and ${\alpha}$-dicarbonyls, such as diacetyl, glyoxal, methyl glyoxal and 2, 3-pentanedione were investigated against the mutagenic heterocyclic amines, such as Trp-P-1, Trp-P-2, Glu-P-1, Glu-P-2 and IQ. Most of the carbonyl compounds suppressed the mutagenicity of heterocyclic amines for S. typhimurium TA98, ${\alpha}$-dicarbonyl compounds showing a higher desmutagenic effect than ${\alpha}$-hydroxycarbonyl compounds. Among the ${\alpha}$-hydroxycarbonyl compounds, glyceraldehyde, glycolaldehyde and dihy-droxyacetone showed more effective desmutagenicity, and diacetyl among the ${\alpha}$-dicabonyl compounds had the highest desmutagenic effect. These carbonyl compounds alone also showed mutagenicity to S. typhimurium TA100 without S-9 mix. The reaction of carbonyl compounds with mutagenic heterocyclic amines also eliminated the mutagenicity of the former for S. typhimurium TA100.

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The Aroma Components of Duchung Tea and Persimmon Leaf Tea (두충차와 감잎차의 향기성분)

  • Choi, Sung-Hee
    • Korean Journal of Food Science and Technology
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    • v.22 no.4
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    • pp.405-410
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    • 1990
  • The aroma components of duchung tea and persimmon leaf tea were collected simultaneous distillation and extraction method. Those were analyzed and identified by GC-MS using a fused sillica capillary column. Seventy seven components, including 17 alcohols, 3 hydrocarbons, 15 ketones, 16 aldehydes, 8 esters,8 acids, 8 heterocyclic compounds and 2 phenols were confirmed in duchung tea. Seventy one components, including 17 alcohols, 10 hydrocabrons, 11 ketones, 13 aldehydes, 8 esters, 6 acids, 5 heterocyclic compounds and 1 phenol were confirmed in persimmon leaf tea. The most abundant components of duchung tea were aldehydes(23.31%) including 2-pentenal and heterocyclic compounds(16.71%) including $epoxy-{\beta}-ionone$. The most abundant components of persimmon leaf tea were alcohols(25.57%) including linalool and aldehydes(19.45%) including hexanal and hydrocarbons(10.40%) including ${\alpha}-copaene$.

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