• Journal of the Korean Chemical Society
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• v.30 no.1
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• pp.101-104
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• 1986

Dialdehydes such as adipaldehyde, glutaraldehyde, and succinaldehyde were readily reduced to give their corresponding 1,6-hexanediol, 1,5-pentanediol, and 1,4-butanediol in good yields in the presence of catalytic amount of hexarhodium hexadecacarbonyl or iron pentacarbonyl in water and methoxyethanol or ethanol at 180$^{\circ}C$ for 4 hr under carbon monoxide atmosphere. Under the same reaction conditions, diketones such as 2,5-hexanedione, 2,4-pentanedione, and 2,3-butanedione afforded their corresponding 2,5-hexanediol, 2,4-pentanediol and 2,3-butanediol in moderate yields. For double hydrohydroxymethylation of dialdehydes or diketones, rhodium or iron carbonyl complexes are more effective than others. Particularly, benzoquinone gave hydroquinone quantitatively.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.491-494
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• 2008

The hydrogen fuel and fuel cell which have high energy efficiency and low pollutant emission are getting interest as an alternative energies due to the fossil fuel exhaust, green house effect and atmospheric pollutant problems. The hydrogen gas is very effective as an alternative energy. But, if it is leaked into the air it forms the mixed gas with the air then the danger of the explosion is risen up. So, the secure the safety is mostly important. In this research, to detect the leakage of the hydrogen rapidly, added the odorant materials which don't include the sulfur component into the hydrogen gas and researched on the effect of each odorant on the performance of the fuel cell. As the results, setting the cumulation electric power on the basis and comparing the pure hydrogen, 2,3-Butanedione 5ppm mixed gas 86.1%, 5-Ethylidene-2-Norbornene 17ppm mixed gas 88.2%, Isovaleraldehyde 10ppm mixed gas 74.8%, Ethyl Isobutyrate 2.2ppm mixed gas 93.5% of performance was shown.

• Journal of the Korean Society of Tobacco Science
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• v.21 no.2
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• pp.119-127
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• 1999

This study was conducted to evaluate the effect of cigarette papers, flax and wood, on the delivery of mainstream smoke. The main components of cigarette papers were cellulose, hemicellulose, lignin, and pectin. Lignin contents, known as precursor of smoke's phenolic compounds, of the flax and wood cigarette papers were 5.8% and 10.6%, respectively. The pyrolysis products of cigarette papers were similar by the profile of total ion chromatogram. But, the area % of some components, such as 1,3-cyclopentanedione, 3,5- dimethyl cyclopentane-1,2-dione, 2-hydroxy-3-methyl-2-cyclopentenone, dihydro-2(3H)-furanone, 3-methyl-2(5H)-fruanone, and 5-methyl-2-furaldehyde delivered through pyrolysis of the flax cigarette paper were higher than that of wood cigarette paper. Otherwise, the area % of some components, such as 2-methyl-cyclopentene-l-one), 2,3-butanedione, 2-cyclopentene-l-one, and 5-hydroxy-2-methyl-furaldehyde, 2-furaldehyde delivered through pyrolvsis of the wood cigarette paper were higher than that of flax cigarette paper. To identify the difference between two cigarette papers, we used the cigarette column filled with the cut cigarette paper instead of the cut tobacco leaf. The amounts of semi-volatile fraction delivered from flax cigarette paper was more than that of wood cigarette paper. But, by using the cut tobacco, there was no big difference of delivery amount between flax and wood cigarette papers. Also, aroma of TPM by collecting from brening cut tobacco wrapped in flax and wood papers showed a different pattern by the electonic nose system. Although the difference between two cigarette papers by using the cut tobacco was smaller than that of cut cigarette paper, this result indicated that the fax and wood had the different effects on the delivery of smoke components as shown in the sensory test results.

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.69-74
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• 2001

Purpose: $^{99m}Tc$-HMPAO is a radiopharmaceutical for imaging cerebral blood flow. HMPAO (RR, SS)-4.8-diaza-3,6,6,9-tetramethylundecan-2,10- dione bisoxime) has three stereoismers such as, meso-. d-, and l-HMPAO. Techentium complexes of meso-HMPAO and d,l-HMPAO are known to have different in vivo brain uptakes. In this study, enantiomers of HMPAO (d-HMPAO and l-HMPAO) were separated from d,l-HMPAO. These enantiomers were labeled with $^{99m}Tc$ and the biodistribution studies were performed in mice. Materials and Methods: An intermediate imine product was produced from 2,3-butanedione monooxime and 2,2-dimethyl-1,3-propanediamine (54% yield) and was reduced into a mixture of three isomers (35% yield). The meso-isomer was separated from d,l-mixture by repeated fractional crystallization (11 % yield). The d- and l-enantiomers were subsequently separated by co-crystallization with optical isomers of tartaric acid (25% and 5% yield. respectively). Each enantiomeric HMPAO was labeled with $^{99m}Tc$ by reacting with $SnCI_2{\cdot}2H_2O\;and\;^{99m}Tc$-pertechnetate. Biodistribution study was performed 1 hr after tail vein injection to ICR mice. Results: Radiochemical purities of each compound were over 80%. In biodistribution study. the brain uptakes of d,l- d- and l-form were 1.34, 1.12 and 1.67% ID/g, respectively. In case of l-lsomer the brain uptake was higher (1.5 fold) than d-isomer. Conclusion: We successfully purified each enantiomeric HMPAO. In biodistribution study of stereoismers of $^{99m}Tc$-HMPAO in mice, l-HMPAO may show better brain image than d,l-HMPAO which was supplied in a commercial kit.

• Animal cells and systems
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• v.5 no.3
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• pp.253-262
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• 2001

Ligand-receptor clustering event is the most important step in leukocyte adhesion and spreading on endothelial cells. Intercellular adhesion molecule-1 (ICAM-1) has been shown to enhance leukocyte adhesion, but the molecular event during the process of adhesion is unclear. To visualize the dynamics of ICAM-1 movement during adhesion, we have engineered stable Chinese hamster ovary cell lines expressing ICAM-1 fused to a green fluorescent protein (IC1_GFP/CHO) and examined them under the fluorescence microscopy. The transfection of IC1_GFP alone in these cells was sufficient to support the adhesion of K562 cells that express $\alpha$L$\beta$2 (LFA-1) integrin stimulated by CBR LFA-1/2 mAb. This phenomenon was mediated by ICAM-1-LFA-1 interactions, as an mAb that specifically inhibits ICAM-1-LFA-1 interaction (RRl/l) completely abolished the adhesion of LFA-1＊ cells to IC1_ GFP/CHO cells. We found that the characteristic of adhesion was followed almost immediately (~10 min) by the rapid accumulation of ICAM-1 on CHO cells at a tight interface between the two cells. Interestingly, ICI_GFP/CHO cells projected plasma membrane and encircled approximately half surface of LFA-1+ cells, as defined by confocal microscopy. This unusual phenomenon was also confirmed on HUVEC after adhesion of LFA-1＊ cells. Neither cytochalasin D nor 2,3-butanedione 2-monoxime an inhibitor of myosin light chain kinase blocked LFA-1-mediated ICAM-1 clustering, indicating that actin cytoskeleton and myosin-dependent contractility are not necessary for ICAM-1 clustering. Taken together, we suggest that leukocyte adhesion to endothelial cells induces specialized form of ICAM-1 clustering that is distinct from immunological synapse mediated by T cell interaction with antigen presenting cells.

• BMB Reports
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• v.29 no.4
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• pp.277-285
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• 1996

In Pseudomonas fluorescens grown on malonate as sole carbon source, acetyl-CoA synthetase was induced, suggesting that malonate is metabolized through acetate and then acetyl-CoA. Acetyl-CoA synthetase was purified 18.6-fold in 4 steps to apparent homogeneity. The native molecular mass of the enzyme estimated by a native acrylamide gel electrophoresis was 130 kDa. The enzyme was composed of two identical subunits with a molecular mass of 67 kDa. Optimum pH was 70. The acetyl-CoA synthetase showed typical Michaelis-Menten kinetics for the substrates, acetate, ATP and CoA, whose $K_m$ values were calculated to be 33.4, 74.8, and 40.7 mM respectively. Propionate. butyrate and pentanoate were also used as substrates by the enzyme, but the rate of the formation of the CoA derivatives was decreased in the order of the increase in carbon number. The enzyme was inhibited by the group-specific reagents diethylpyro-carbonate, 2,3-butanedione, pyridoxal-5'-phosphate and N-bromosuccinimide. In the presence of substrates the inactivation rate of the enzyme, by all of the group-specific reagents mentioned above decreased, indicating the presence of catalytically essential histidine, arginine, lysine and tryptophan residues at or near the active site. Preincubation of the enzyme with ATP, $Mg^{2+}$ resulted in the increase of its susceptibility to diethylpyrocarbonate, suggesting that ATP, $Mg^{2+}$ may induce a conformational change in the active site exposing the essential histidine residue to diethylpyrocarbonate. The enzyme was acetylated in the presence of acetyl-CoA, indicating that this is one of acyl-enzyme.