• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.04a
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• pp.613-615
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• 2008

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.999-1006
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• 2004

The selective media including NPC agar, DHL agar, MacConkey agar, and Cetrimide desoxycholate agar were compared to determine selectivity for the growth of bacteria Cetrimide desoxycholate agar was better than NPC agar, DHL agar, and MacConkey agar for the growth of psychrotrophic grarn-negatve bacteria including Pseudomonas. and for the inhibition of gram positive bacteria The specificity of resazurin reduction time test was investigated to determine post-pasteurization contamination of market milk. Equal volume of Cetrimide desoxycholate broth was added to market milk, which was then incubated at $21^{\circ}C$ for 18 hours. The growth of bacteria in the incubated milk was detected in resazurin reduction time test. The results in resazurin reduction time test and total bacteria number count of market milk after storage at $7^{\circ}C$ were relatively correlated each other. Pseudomonas was isolated most frequently from the market milk stored at $7^{\circ}C$ for 10 days, and Acinetobacter and Aeromonas followed. Acinetobacter, Pseudomonas and Enterobacter were frequently isolated from the mixture of market milk and Cetrimide desoxycholate broth incubated at $21^{\circ}C$ for 18hours in resazurin reduction time test.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.123-129
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• 2005

In situ permeable reactive barrier (PRB) technologies have been proposed to reductively remove organic contaminants from the subsurface environment. The major reactive material, zero valent iron ($Fe^0$), is oxidized to ferrous iron or ferric iron in the barriers, resulting in the decreased reactivity. Iron-reducing bacteria can reduce ferric iron to ferrous iron and iron reduced by these bacteria can be applied to dechlorinate chlorinated organic contaminants. Iron reduction by iron reducing bacteria, Shewanella algae BrY, was observed both in aqueous and solid phase and the enhancement of TCE removal by reduced iron was examined in this study. S. algae BrY preferentially reduced Fe(III) in ferric citrate medium and secondly used Fe(III) on the surface of iron oxides as an electron acceptor. Reduced iron formed reactive materials such as green rust ferrihydrite, and biochemical precipitation. These reactive materials formed by the bacteria can enhance TCE removal rate and removal capacity of the reactive barrier in the field.

• Journal of the Korean Chemical Society
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• v.22 no.4
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• pp.259-267
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• 1978

In order to find out the selective reducing characteristics of lithium borohydride, borane, and borane-lithium chloride (1 : 0.1) in the reduction of carbonyl compounds, five representative equimolar mixtures of carbonyl compounds were chosen; benzaldehyde-acetophenone, benzaldehyde-2-heptanone, 2-heptanone-benzophenone, acetophenone-benzophenone, and 2-heptanone-acetophenone, and reacted with limited amount of lithium borohydride, borane or borane-lithium chloride (1 : 0.1) in tetrahydrofuran (THF) at $0^{\circ}$. Borane-lithium chloride (1 : 0.1) showed the excellent selectivity, however, lithium borohydride and borane also exhibited good selectivity except for the 2-heptanone-acetophenone.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2255-2261
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• 2000

To eliminate $NO_x$ in diesel emission. selective catalyst reduction (SCR) was used in real diesel engine. Among the SCR methods, metal oxide and perovskite catalysts were introduced in this paper. The removal efficiencies with various major, promoter catalysts on ${\gamma}-Al_2O_3$ at different reaction temperature were investigated, and $LaCuMnO_x$ catalyst which has high removal efficiency at the temperature of real diesel exhaust gas was selected. $NO_x$ reduction was carried out over these catalysts in the flow-through type reactor using by-pass ($SV=3,300h^{-1}$). Under the given condition to this study, perovskite catalysts showed considerably high removal efficiency and $LaCuMnO_x$ was the best one among these catalysts in the temperature range of $150{\sim}450^{\circ}C$.

• Clean Technology
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• v.21 no.3
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• pp.153-163
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• 2015

The effects of H₂O and residue SO₂ in flue gases on the activity of the Fe/zeolite catalysts for low-temperature NH₃-SCR of NO were investigated. And the addition effect of Mn, Zr and Ce to Fe/zeolite for low-temperature NH₃-SCR of NO in the presence of H₂O and SO₂ was investigated. Fe/zeolite catalysts were prepared by liquid ion exchange and promoted Fe/zeolite catatysts were prepared by liquid ion exchange and doping of Mn, Zr and Ce by incipient wetness impregnation. Zeolite NH₄-BEA and NH₄-ZSM-5 were used to adapt the SCR technology for mobile diesel engines. The catalysts were characterized by BET, X-ray diffraction (XRD), SEM/EDS, TEM/EDS. The NO conversion at 200 ℃ over Fe/BEA decreased from 77% to 47% owing to the presence of 5% H₂O and 100 ppm SO₂ in the flue gas. The Mn promoted MnFe/BEA catalyst exhibited NO conversion higher than 53% at 200 ℃ and superior to that of Fe/BEA in the presence of H₂O and SO₂. The addition of Mn increased the Fe dispersion and prevented Fe aggregation. The promoting effect of Mn was higher than Zr and Ce. Fe/BEA catalyst exhibited good activity in comparison with Fe/ZSM-5 catalyst at low temperature below 250 ℃.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.437-440
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• 1985

Organic azides were reduced to organic amines in the presence of tetracarbonylhydridoferrate(O) as a highly selective reducing agent at room temperature under carbon monoxide atmosphere. Particularly, benzoylazide gave ethylphenylcarbamate at room temperature but gave benzamide quantitatively at -40$^{\circ}$ in the presence of tetracarbonylhydridoferrate under carbon monoxide atmosphere.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.360-366
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• 1975

Selective reduction of carbonyl group with zinc borohydride in the presence of ester functional group was demonstrated with seven representative keto esters. Either hydroxy esters or lactones were obtained in good yields; ethyl 6-hydroxyheptanoate ($83.0{\%}$), ethyl 2,6-dimethyl-4-hydroxy-2-cyclohexenecarboxylate ($82.3{\%}$), ethyl p-(${\alpha}$-hydroxyethyl)-phenylacetate ($78.9 {\%}$), 4-phenylbutyrolactone ($70.2{\%}$), and 3-phenylphthalide ($92.4{\%}$) were obtained from the corresponding keto esters.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.355-359
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• 1975

Reduction of epoxy ketones with zinc borohydride proceeds selectively to the corresponding epoxy alcohols in good yields. Thus we obtained 3,4-epoxy-4-methyl-2-pentanol($79.8{\%}$), trans-isophorol oxide ($89.5{\%}$), trans-2-benzal-cyclohexanol oxide ($84.1{\%}$) and trans-chalcol oxide ($97.9{\%}$, crude) from the corresponding epoxy ketones.

• Clean Technology
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• v.12 no.2
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• pp.87-94
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• 2006

The reduction of $SO_2$ to elemental sulfur by CO over a series of iron niobate with nominal Nb/Fe atomic ratios of 1/0, 10/1, 5/1, 1/1, 1/5, 1/10 and 0/1 was studied with a flow fixed-bed reactor. Strong synergistic phenomena in catalytic activity and selectivity were observed for the iron niobate catalysts, and the best catalytic performance was observed for the catalyst with Fe/Nb atomic ratio of 1/1. The active phase of the activated iron niobate catalysts was identified to be $FeS_2$ using XRD and XPS. Selective reduction of $SO_2$ by CO was followed by the COS intermediate mechanism.