• Title/Summary/Keyword: Benzene

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Removal of Benzene by the Fluidized Bed Bioreactor including Microbial Consortium (혼합균주를 함유한 유동층 생물반응기를 이용한 벤젠의 제거)

  • 주준걸;김연재;조성기;오광중;김종우;김동욱
    • KSBB Journal
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    • v.19 no.3
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    • pp.206-209
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    • 2004
  • MY microbial consortium were obtained from sludges of wastewater to degrade benzene effectively and Rhodococcus ruber DSM 43338T was identified as major microorganism. The fluidized bed biofilter including MY microbial consortium showed critical removal rate of benzene at 32 g/㎥ h, and maintained stable removal efficiency for 17 days of continuous operation.

Antitumor constituents from some Korean medicinal plants

  • Bae, Ki-Hwan
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.56-61
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    • 1998
  • For the screening of bioactive natural products, the benzene or methanol extracts from 93 medicinal plants of Korea were prepared, and tested for the cytotoxicity against L1210 cells and for the antitumor action (Bae et al., 1992 and 1996). Of 93 extracts tested, 6 samples showed a cytotoxicity in both benzene and methanol extract, 39 samples in benzene and 13 samples in methanol extract. The benzene extract of the root of Scutellaria indica L., Sophora fIavescens Solander ex Aiton, Carpesium abrotanoides L., Gymnaster koraiensis (Nakai) Kitamura, Pyrola japonica Klenze, and Forsythiae Fructus showed a potent cytotoxic activity. This observation led to isolate active cytotoxic components, some of which demonstrated some antitumor action. In addition, the structure-activity relationship was discussed.

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Prediction of Pervaporation Performance Using Solubility Parameter Calculation

  • John R. Dorgan;Nam, Sang-Yong
    • Korean Membrane Journal
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    • v.5 no.1
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    • pp.36-42
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    • 2003
  • A Prediction of pervaporation performance was studied by solubility parameter calculation approach for the benzene/cyclohexane mixture system using rubbery blend membrane with various solubility parameters. The solubility parameter of the rubbery blend membranes were controlled with different blend ratio of the poly(acrylonitrile-co-butadiene), poly(styrene-co-butadiene) and poly(vinyl chloride). Screening of blend formulations was accomplished by simple swelling tests. When the content of NBR is increased, the swelling of both benzene and cyclohexane are decreased. However, the ratio of benzene swelling to swelling by cyclohexane (the swelling selectivity) increases. The same is true for blends in which the PVC content is increased. Adoption of a solubility parameter calculation provides an a priori methodology for seeking the best blend formulation.

Screening on Cytotoxicity of Medicinal Plants against L1210 Cell (L1210 세포에 대한 약용 식물의 세포독성 검색)

  • Bae, Ki-Hwan;Min, Byung-Sun;Do, Dong-Sun;Kim, Nam-Soo;Yang, Gi-Jong;Ahn, Byung-Zun
    • YAKHAK HOEJI
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    • v.36 no.5
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    • pp.491-495
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    • 1992
  • For the research of cytotoxic natural products, 50 medicinal plants were extracted with benzene and methanol, separately, and screened against L1210 cells. From the results(Table I), 6 samples showed cytotoxicity both in benzene and methanol extracts of 17 samples in benzene extracts and 3 samples in methanol extracts, respectively. Generally, the cytotoxicity exhibited high frequency (34%) in benzene extract but low frequency in methanol extract (6%), it meant that active cytotoxic components had less polarity. $ED_{50}$ values less than $10\;{\mu}g/ml$ were observed in 17 medicinal plants.

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Raman Frequencies Calculated at Various Pressures in Phase I of Benzene

  • Tari, Ozlem;Yurtseven, Hamit
    • Journal of the Korean Chemical Society
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    • v.57 no.2
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    • pp.204-209
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    • 2013
  • We calculate in this study the pressure dependence of the frequencies for the Raman modes of A ($A_g$), B ($A_g$, $B_{2g}$) and C ($B_{1g}$, $B_{3g}$) at constant temperatures of 274 and 294K (room temperature) for the solid phase I of benzene. Using the mode Gr$\ddot{u}$neisen parameter of each lattice mode, which correlates the pressure dependence of the crystal volume and the frequency, the Raman frequencies of those modes are computed for phase I of benzene. Our results show that the Raman frequencies of the three lattice modes (A, B and C) increase as the pressure increases, as expected. The temperature effect on the Raman frequencies is not significant, which can be explained by the experimental measurements.

Combinatory Effects of Benzene, Toluene and Xylene on the Induction of Rat Liver Microsomal Enzymes and Their Metabolites (흰쥐 간의 microsomal enzymes의 유도에 있어서 benzene, toluene과 xylene의 복합적인 영향과 그들의 대사산물)

  • 김기웅;박상신;김태균;문영한;장성근
    • Toxicological Research
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    • v.12 no.1
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    • pp.9-15
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    • 1996
  • We studied the effects of a single, combined and mixed exposure of benzene, toluene and xylene on the activities of rat liver microsomal AHH, ADH and ALDH, and the excretion of their metabolites in urine. The AHH activities of the rats treated in combination and mixture were slightly higher and/or similar to those rats treated with single solvent, while the reverse effects were observed for ADH and ALDH. Similar effects were observed when the metabolites were examined in urine (p < 0.01). These results suggest that each solvent might interJkre the induction and action of ADH and ALDH, and decrease the excretion of their metabolites into urine.

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The Charge Transfer Complexes of Monoalkylbenzene with Iodine in Carbon Tetrachloride (I)

  • Oh-Cheun Kwun
    • Bulletin of the Korean Chemical Society
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    • v.1 no.2
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    • pp.62-68
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    • 1980
  • Ultraviolet spectrophotometric investigations have been carried out the systems of monoalkylbenzene with iodine in carbon tetrachloride. The results reveal the formation of one to one molecular complexes. The equilibrium constants for these complexes of representative monosubstituted benzene reveal the following order of increasing stability: benzene < methyl- < ethyl- < n-propyl-benzene. The value of ${\Delta}H$, ${\Delta}G$, and ${\Delta}S$ for interaction of a number of monoalkyl substituted benzene with iodine has been determinated. In general, as ΛH becomes increasingly negative, corresponding decreases in ${\Delta}G$ and ${\Delta}S$ values are observed, and these variation are linear. The thermodynamic constants become increasingly negative with increasing monoalkyl substitution of the aromatic donor nucleus. The complex bond is therefore weak, and its formation is accompanied by relatively small entropy changes.

Carbonylation of 1-Bromo-2,6-bis(bromomethyl)benzene Catalyzed by Cobalt Carbonyl

  • Sang Chul Shim;Shin Ae Chae;Dong Yeob Lee;Young Zoo Youn;Jae Goo Shim;Chil Hoon Doh
    • Bulletin of the Korean Chemical Society
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    • v.14 no.4
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    • pp.481-485
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    • 1993
  • Dialkyl 1-bromobenzene-2,6-diacetates were easily prepared by the carbonylation of the moiety of benzylic bromide in 1-bromo-2,6-bis(bromomethyl)benzene with alcohol in the presence of NaOAc< TEX>${\cdot}$3H$_2$O and a catalytic amount of Co$_2$(CO)$_8$under the atmospheric pressure of carbon monoxide at room temperature in excellent yield. Alkyl 2,6-bis(alkoxymethyl)benzoates were obtained by the carbonylation of the moiety of aryl bromide in 1-bromo-2,6-bis(alkoxymethyl)-benzene, which derived from 1-bromo-2,6-bis(bromomethyl)benzene, alcohol, NaOR, and CH$_3$I under the same conditions. Alkyl 2,6-bis(carboxymethyl)benzoate was also obtained in a trace amount for 24 hrs at room temperature.