• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.649-656
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• 1992

The synthesis of epichlorohydrin was carried out by the epoxidation of allyl chloride with tert-butyl hydroperoxide(TBHP) over silica supported molybdenum catalyst. Kinetic study was performed at $60-80^{\circ}C$ and 10 atm with the molar ratio of TBHP/Allyl chloride between 0.01 and 0.1 in a batch reactor. The epoxidation of allyl chloride was inhibited by tert-butyl alcohol and kinetic data could be represented by Michaelis-Meten type rate equation. The reaction mechanism could be explained by the combination of reversible adsorption of TBHP and tert-butyl alcohol accompanied by reaction of allyl chloride with TBHP adsorbed on $Mo/SiO_2$ catalyst.

• Toxicological Research
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• v.14 no.2
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• pp.157-161
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• 1998

The mechanism of active aldehyde-induced liver disease and the enzymatic basis of detoxification were investigated using normal rat liver cell, Ac2F. Aliphatic alcohols including l-decyl alcohol, l-nonanol, l-heptanol, l-hexanol, l-propanol and allyl alcohol exerted a dose- and time-de-pendent toxicity to Ac2F cells. The extent of their toxicities in buthionine sulfoximine (inhibitor of glutathione synthesis) pretreated cells was greater than in pargyline (inhibitor of aldehyde dehydrogenase, ALDH). On the other hand, the toxicity of these alcohols were not affected by 4-methylpyrazole (inhibitor of alcohol dehydrogenase, ADH). These results suggest that the contents of glutathione (GSH) seems to be very important in protecting the cells from toxicants such as aliphatic alcohols.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.640-643
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• 1996

The vapor phase hydrogen trancefer reaction between acrolein and isopropyl alcohol has been investigated over $Ag_2O$-Cao catalyst. A high selectivity of allyl alcohol was obtained at 88.7% with conversion of 75.4%.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.286-292
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• 2007

Free amino acids and volatile compounds of fresh garlic and its liqueur were investigated to search elution profile of those components as basic data for development of garlic liqueur. The garlic was soaked in 20% alcohol solution and then sampled every week for 5 weeks. The major free amino acids were L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L-proline, L-asparagine and L-serine. Neutral amino acids such as L-threonine, L-proline, L-valine and L-leucine, and aromatic amino acids such as tyrosine and phenylalanine were eluted over 80% of those content in fresh garlic after 3 weeks of soaking, but acidic, basic and sulfur containing amino acids were below 80% even after 5 weeks. Sulfide compounds such as diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithi in, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate and diallyl sulfide were identified as major volatile compounds of fresh garlic by using GC/MS. Among volatile compounds of fresh garlic, allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide and 3,4-dimethoxy furan were eluted to liqueur, but those compounds except 3,5-diethyl-1,2,4-trithiolane were lowered in liqueur during soaking. Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyr-an-4-one were generated newly and their content increased in liqueur during soaking.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1637-1642
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• 2007

The objectives of this study were to compare the aroma characteristics and antioxidant activity of raw and heated garlic ($130^{\circ}C$, 2 hr) from different cultivation areas (Danyang, Seosan, Uiseong Namhae, Namdo, Daeseo and China). The volatile compounds were extracted by simultaneous steam distillation extraction and identified with gas chromatography/mass spectrometer. The major volatile compounds of raw garlic were sulfur compounds such as diallyl disulfide, methyl-2-propenyl trisulfide, di-2-propenyl trisulfide etc. After heating, the major volatile compounds were allyl mercaptan, methyl pyrazine, 2,2-dimethyl-1,3-dithiane, 2-propenyl propyl disulfide, allyl methyl sulfide, allyl alcohol, and allyl sulfide etc. The DPPH radical scavenging activity (EDA, %) of volatile compounds from raw garlic and heated garlic was increased in a dose-dependent manner. The antioxidant activities (EDA, %) of volatile compounds from raw garlic cultivated in Danyang, Namhae and China were 20.07, 34.62, and 9.71% respectively. After heating, these values were increased to 79.90, 93.59, and 77.26% respectively. Results showed that heat treatment significantly enhanced the antioxidant activities (EDA, %) of the garlic.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.469-473
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• 2006

Film-forming yeasts generate an undesirable yeasty flavor in fermented vegetables such as kimchi in the presence of oxygen. Antimicrobial materials including garlic oil (GO), heated garlic (HG), and allyl alcohol (AA) were investigated for use as alternative natural food preservatives to inhibit the growth of film-forming yeasts in fermented vegetables. Using the fermentation of cucumber pickles as a model system, GO, HG, and AA were effective in preventing film formation at concentrations of 0.006, 3.0, and 0.02%, respectively. The effectiveness of HG in preventing the growth of a film yeast, Hansenula anomala, was not influenced by pH, while that of potassium sorbate, a typical anti-yeast food preservative, was highly dependent on pH. All tested materials were effective when added at the beginning of fermentation due to their negligible inhibitory activity toward lactic acid bacteria.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.510-514
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• 2011

Photodissociation dynamics of allyl alcohol ($H_2C$=CH-$CH_2OH$) has been investigated at 205 - 213 nm along the UV absorption band by measuring rotationally-resolved laser-induced fluorescence spectra of OH radicals. Observed energy partitioning of the available energy among products at all photon energies investigated was similar and the barrier energy for OH production is about 574.7 kJ/mol from the OH yield measurements. The potential energy surfaces for the $S_0$, $T_1$, and $S_1$ excited states along the dissociation coordinate were obtained by ab initio quantum chemical calculations. The observed energy partitioning was successfully modeled by the "barrier-impulsive model" with the reverse barrier and the geometry obtained by the calculated potential energy surfaces. The dissociation takes place on the $T_1$ excited state potential energy surface with an energy barrier in the exit channel and a large portion of the photon energy is distributed in the internal degrees of freedom of the polyatomic products.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.539-541
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• 2012

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 2002.08a
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• pp.53-53
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• 2002

• Journal of the Korea Institute of Military Science and Technology
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• v.8 no.2 s.21
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• pp.67-76
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• 2005

We synthesized an energetic prepolymer(glycidyl dinitro propyl formal, GDNPF) for plastic-bonded explosive and measured its thermodynamic parameters. Glycidyl dinitro propyl formal(GDNPF) as an energetic monomer was epoxidized from allyl-2,2-dinitro propyl formal which is reacted with dinitro propyl alcohol and excess allyl alcohol, and then energetic polymer of GDNPF was polymerized by cationic ring opening polymerization. Thermodynamic parameters were obtained from the ceiling temperature($T_c$) values of 1 mole monomer at reaction temperature. We varied feed rate of monomer, concentration of initiator and monomer to control molecular weight and polydispersity of prepolymer (GDNPF). The activated monomer polymerization has been executed with precisely controlled feed of GDNPF monomer to reactor in the complex state catalyst generated by $BF_3{\cdot}(C_3H_5)_2$ and 1,4-butanediol in $C_2H_4Cl_2$. Number average molecular weight(Mn), polydispersity(Pd), hydroxy number and glass transition temperature($T_g$) of prepolymer(GDNPF) were $2,500{\sim}3,000,\;1.2{\sim}1,3,\;0.6{\sim}0.8eq/kg\;and\;-20{\sim}-25^{\circ}C$ respectively.