• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.236-240
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• 1989

The isolated bacterial strain 1K1 able to grow on extremely high concentration of toluene was morphologically and physiologically best described as Pseudomonas putida. This strain could grow on at least eight aromatic compounds, e.g., benzene, benzoate, phenol, o-cresol, m-cresol, toluene, m-tolunte, and xylene, but did not Brow on alkanes, such as hexane, octane, decane, and cyclohexane. Strain 1K1 could grow on above 95% toluene, but it could not grow on above 1% of other aromatic compounds. In the point of survival, strain 1K1 was resistant to high concentration of alkanes, appreciably resistant to toluene and xylene, and damaged by to other aromatic compounds. Strain 1K1 which grew on high concentration of toluene had irregular cell shape in comparing with normal cell shape of the genus Pseudomonas. Strain 1K1 was shown to have at least two aromatic compound dissimilation pathway, one for benzoate and the other for toluene.

• Fire Science and Engineering
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• v.32 no.1
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• pp.1-6
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• 2018

The flash point is one of the most important parameters used to characterize the ignition and explosion hazards of liquids. Flash points were measured for several binary systems containing toluene, including {methanol+toluene}, {ethanol+toluene}, and {1-propanol+toluene}. Experiments were performed according to the standard test method using a SETA closed cup flash point tester. The measured flash points were compared with the predicted values calculated using the following $G^E$ models: Wilson, NRTL, and UNIQUAC. The average absolute deviation between the predicted and measured lower flash point was less than 1.69 K.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1197-1202
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• 2007

Adsorption experiments of binary mixed gases composed of acetone/methylethylketone (MEK), MEK/benzene, MEK/toluene, and benzene/toluene were carried out on activated carbon fixed-bed. The variations of equilibrium adsorption capacity according to type and fraction of binary gas were investigated. In case of binary gases composed of acetone/MEK and benzene/toluene, equilibrium adsorption capacities of MEK and toluene were increased according to the increase of fraction of MEK and toluene, but equilibrium adsorption capacities of acetone and benzene were decreased. In case of binary gases composed of MEK/benzene and MEK/toluene, equilibrium adsorption capacities of benzene and toluene were increased according to the increase of fraction of benzene and toluene, but equilibrium adsorption capacities of MEK was decreased.

• YAKHAK HOEJI
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• v.40 no.5
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• pp.545-549
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• 1996

Male Sprague-Dawley rats were exposed to the toluene at 3,000${\pm}$200ppm via inhalation for two hours in the single inhalation group and three weeks by two hours per day, six da ys per week in the repeated inhalation group. The blood toluene concentration in the repeated inhalation group was significantly lower than that in the single inhalation group after 210 and 240 minutes of exposure. The peak concentration of blood toluene was 58.13${\pm}$4.63${\mu}$g/ml in the single inhalation group and 54.24${\pm}$6.87mcg/ml in the repeated at the end of 120 minutes of the exposure. The behavioral change of rats for the initial 30 minutes of the toluene inhalation showed mildly increased movement and excitement but remained calm and inhibitory behaviors after that period; more inhibitory behaviors in the single inhalation group compared with the repeated inhalation group. In open-field test, after the termination of the toluene inhalation, no difference had been statistically observed between the toluene inhalation group and the control group in ambulation, rearing, preening and grooming.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.22-29
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• 2001

To evaluate the cutaneous injury in liver damaged rats by toluene application to the skin, toluene(35mg/㎤) was sequentially applied for 5 days to the dorsal skin of liver damaged rats with $CCl_4$ (6 times ever other day:0.1$m\ell$/100 g body weight-50% $CCl_4$in olive oil). The cutaneous ultrastructural changes were unexoectably not observed in liver from $CCl_4$-treated rats although necrotic liver damage appeared under light microscope. In these animals by the application of toluene to rat skin the cutaneous xanthine oxidase activity was significantly increased(p<0.05), but cytochrome P450 content was not different from that of the control or only $CCl_4$-treated rats. On the other hand, the cutaneous superoxide dismutase and catalase activities in liver damaged animals were significantly respectively(p<0.05, p<0.001), decreased by toluene application to the skin compared with control and especially the former enzyme activity was significantty decreased(p<0.01), compared with that of liver damaged rate rat but glutathione peroxidase, glutathione-S-transferase activities were not significantly different from those of the control or liver damaged rats. Futhermore, the reduced gluathione content of skin was also significantly decreased by toluene application to the liver damaged animals. In conclusion, the great deposits of cerrous peroxide and ultramorphological changes in skin tissue of liver damaged animals by toluene application may be responsible for the oxygen free radical.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.1
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• pp.61-69
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• 1997

To evaluate an effect of pathological liver damage on the toluene metabolism, the rate were induced acute liver damage with 3 times $CCl_4$ injection (0.1 ml of 50 % in olive oil/100 g body wt.) three days. In the present animal molel, the injection of toluene(0.3 ml of 50 % in olive oil) showed the more decreased urine hippuric acid throughout 24 hr in the liver damage induced animals($CCl_4$-pretreated rats) than normal group. The activities of hepatic aniline hydroxylase, benzylalcohol dehydrogenase and benzaldehyde dehydrogenase were significantly decreased in $CCl_4$-pretreated rats than the normal group at 24 hr after injection of toluene. Furthermore, the benzaldehyde dehydrogenase in pooled liver of $CCl_4$-pretreated rats showed similiar $K_m$ value, but showed the more decreased $V_{max}$ value compared with the normal group by the injection of toluene. These results suggest that the rats induced liver damage with $CCl_4$ may reduce the toluene metabolism.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.519-525
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• 2008

Biodegradation of toluene, styrene and hydrogen sulfide as model compounds of volatile organic compounds and odor from waste gas was investigated experimentally in a biotrickling filter. This study focussed on the description of experimental results with regard to operating conditions. The effect of varying $H_2S$ load rate and inlet concentration was investigated under autotropic and mixotropic environmental conditions. The $H_2S$ removal efficiencies of greater than 99% were achieved at $H_2S$ loads below $10g/m^3{\cdot}hr$ for each environment. It was observed that the maximum elimination capacity of mixotrophic filter was achieved a little greater than the one of autotrophic filter. The biofiltration of toluene and styrene in trickling bed was examined under different gas flow rates, load rates, and inlet concentrations. Below $40g/m^3{\cdot}hr$ of toluene loading, the elimination capacity and loading were identical and it was completely destroyed. In high loading of toluene, the biotrickling filter was operated at its maximum elimination capacity. In the inlet concentration of 0.2, 0.5, and $1.0g/m^3$, the maximum elimination capacity of toluene showed 40, 45, and $60g/m^3{\cdot}hr$, respectively. After a short adaptation period, it was demonstrated that the results of styrene in originally toluene adapted bioreactor was similar with the ones of toluene. However, the performance of filer for styrene is generally a little lower than for toluene. The operating conditions (including liquid flow rate etc.) allowing the highest removal efficiency should be determined experimentally for each specific case.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.375-383
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• 2000

A mixed culture isolated from petroleum-contaminated soil was enriched on toluene as a sole carbon and energy source, and degradation characteristics of BTEX(Benzene, Toluene, Ethylbenzene, Xylenes) was observed. In the single-substrate experiments, all the BTEX compounds were degraded, and it was degraded as following orders; toluene, benzene, ethylbenzene, and p-xylene. In the degradation experiments of BTEX mixtures, the degradation rate was decreased compared to that in the single substrate experiment and ethylbenzene was degraded faster than benzene. In the experiments of binary-mixtures, various substrate interactions such as inhibition, stimulation, and non-interaction were observed, and ethylbenzene was shown to be most potent inhibitor of BTEX degradation. In the degradation characteristic studies of xylene isomers, m-xylene and p-xylene were degraded as carbon sources, and it was stimulated in the presence of either benzene or toluene. However, degradation of o-xylene was enhanced only in the presence of benzene.

• KSBB Journal
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• v.13 no.5
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• pp.561-568
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• 1998

Two cometabolic trichloroethylene (TC) degraders, Pseudomonas putida F1 and Burkholderia (Pseudomonas) cepacia G4, were found to catabolize phenol, benzene, toluene, and ethylbenzene as carbon and energy sources. Resting cells of P. putida F1 and B. cepacia G4 grown in the presence of toluene and phenol, respectively, were able to degrade not only benzene, toluene and ethylenzene but also TCE and p-xylene. However, these two strains grown in the absence of toluene or phenol did not degrade TCE and p-xylene. Therefore, it was tentatively concluded that cometabolic degradation of TC and p-xylene was mediated by toluene dioxygenase (P. putida F1) or toluene-2-monooxygenase (B. cepacia G4). Maximal degradation rates of BTEX and TCE by toluene- and phenol-induced resting cells of P. putida F1 and B. cepacia G4 were appeared to be 4-530 nmol/(min$.$mg cell protein) when a single compound was solely served as a target substrate. In case of double substrates, the benzene degradation rate by P. putida F1 in the presence of toluene was decreased up to one seventh of that for the single substrate. TCE degradation rate was also linearly decreased as toluene concentration increased. On the other hand, toluene degradation rate was enhanced by benzene and TCE. For B. cepacia G4, degradation rates of TCE and toluene increased 4 times in the presence of 50 ${\mu}$M phenol. From these results, it was concluded that a degradation rate of a compound in the presence of another cosubstrate(s) could not be predicted by simply generalizing antagonistic or synergistic interactions between substrates.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.64-73
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• 2007

The catalytic activity of transition metals (Cu, Co, Mn, Fe and Ni) supported on ${\gamma}-Al_2O_3$ for the oxidation of toluene was investigated in the microreactor of fixed-bed type. The catalytic activity of transition metals for the oxidation of toluene turned out to be increasing in the order of Ni$Cu/{\gamma}-Al_2O_3$ catalysts for the oxidation of toluene increased with the increasing loadings of copper, reached the maximum activity at 5% loadings of copper, and decreased with higher loadings of copper in the catalysts. The activity of $Cu/{\gamma}-Al_2O_3$ catalysts for the oxidation of toluene decreased with the increasing calcination temperatures. This might result from the decreasing surface area of catalysts due to the sintering of copper oxide as well as ${\gamma}-Al_2O_3$ supports. The 5wt% $Cu/{\gamma}-Al_2O_3$ catalysts calcined at $400^{\circ}C$ for 4 hrs in the air showed the highest activity for the oxidation of toluene. Mutual inhibition was observed for the binary mixture of toluene and xylene. The activity of the easy-to-oxidize toluene was greatly decreased while the difficult-to-oxidize xylene was slightly decreased in the binary mixture of toluene and xylene. It might suggest that the inhibition of toluene and xylene in the binary mixture resulted from the competitive adsorption for the adsorbed oxygen on the catalytic surface.