• Food Science and Preservation
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• v.8 no.1
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• pp.60-65
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• 2001

To investigate the effect of Acetobacter on qualities of potato vinegars, potato vinegars were produced through acetic acid fermentation using 3 Acetobacters such as Acetobacter sp. PA97, Acetobacter sp. PA96 and Acetobacter pasterianus JK 99. There were little difference in pH(2.90∼3.09) and total acidities(5.30∼5.60%) of 3 potato vinegars. However potato vinegar(II) fermented by Acetobacter sp. PA96 showed a little difference in color values with other potato vinegars. Except acetic acid in each potato vinegars, the contents of citric acid, oxalic acid, succinic acid were high in potato vinegar(I), malic acid in potato vinegar(II) and lactic acid in potato vinegar(III). The contents of glutamic acid alanine, histidine and proline were high in all potato vinegars. The major volatile components in 3 potato vinegars were acetic acid, isoamyl acetate, isobutyl acetate, 3-methyl-1-butanol, 3-methyl-butanoic acid and phenethyl alcohol. Also composition ratio of volatile components was a little difference among 3 potato vinegars.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1177-1179
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• 1996

A static headspace gas chromatographic (HSGC) technique was used to quantify toluene and other solvents (methanol, isopropyl alcohol, methyl ethyl ketone and ethyl acetate) in food packaging films. Comparison of retention times and coefficient variations for standard solvents showed consistent retention time and good reproducibility. Therefore, this method using static HSGC proved to be superior in rapidity and reproducibility, and is thought to be adaptable to analysis of a large number of samples. The methanol content was $N.D.\;(not\;detected){\sim}0.939\;mg/m^2$, toluene $N.D.{\sim}1.403\;mg/m^2$, melthyl ethyl ketone $N.D.{\sim}0.932\;mg/m^2$, total solvent content was $N.D.{\sim}2.433\;mg/m^2$.

• Journal of the Korean Applied Science and Technology
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• v.29 no.3
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• pp.495-502
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• 2012

Using the Sedimentation method it's possible to get $TiO_2$ particle from which by this research, $TiO_2$ particle was produced. The parameter in the kind of the temperature and the alcohol solvent used $TiO_2$ particle production investigated crystal structure of $TiO_2$ particle and the influence exerted on the size of the particle and the form. After scanning electron microscope (SEM) analyzed methyl alcohol, iso-propylalcohol and tert-butylalcohol used by a solvent at the $TiO_2$ particle production, iso-propylalcohol was most effective. And after an thermogravimetric analyzer method was used, the anatase structure was maintained $500^{\circ}C$ by $200^{\circ}C$, but it was converted by the rutile structure by $800^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.316-321
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• 2020

Changes in flavor compounds in pine mushroom (Tricholoma matsutake) liquor added with pine tree chips were analyzed using gas chromatography/mass spectrometry. While three flavor compounds were detected in the control, fifteen were detected in the pine mushroom liquor added with pine tree chips. After eight-weeks of aging, the relative concentrations of β-fenchyl alcohol, 2-octanol, and methyl cinnamate, which are distinctive flavor characteristics of the pine mushroom, increased by 67.57%, 2.14%, and 0.94%, respectively, when pine tree chips were added (5%). Principal component analysis revealed that although flavor characteristics of the pine mushroom liquor were affected by the increased production of β-fenchyl alcohol due to the addition of pine tree chips, the aging time exerted a greater influence on flavor.

• Journal of the Korean Geotechnical Society
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• v.15 no.5
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• pp.291-300
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• 1999

Surfactant flushing for enhancing the removal of BTEX from contaminated sand/clay mixtures was investigated. Eight soil columns packed with relatively undisturbed BTEX contaminated soils, were leached with water, methyl alcohol and then flushed with surfactant with or without several additives. Initial concentrations of BTEX mixture range from 278mg/kg to 1975mg/kg. Initial BTEX removal efficiency was 98% when the contaminated soil was flushed with water of 850 pore volumes. Because of tailing effect, water flushing could not remove below 8mg/kg concentrations during the experimental period. Eventually, the most effective surfactant for flushing was turned out to be 4% SOFTANOL(equation omitted)-90 with 3% ethyl alcohol and 3% SXS. In interrupted flow conditions, the removal efficiency was 99.5% with the flushed water of 95 pore volumes. The BTEX mixture removed from the soil columns during the surfactant flushing ranges from 84.5% to 99.5% of the initial amount for both water leaching(850 pore volumes) and surfactant flushing(95-165 pore volumes), respectively. Test results indicated that surfactant flushing could enhance the removal of BTEX mixture from contaminated soils and could reduce the aqueous phase BTEX mixture concentration in leachate.

• Applied Biological Chemistry
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• v.32 no.3
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• pp.232-239
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• 1989

Three types of Korean strawberries, Gardian cultivated in vinyl house, Gardian cultivated on the field and Bogyo, at early variety, on the field were harvested after $10{\sim}34$ days from falling of flowers to investigate the chemical changes of fruits during maturing. The initial pH range after 10 days from falling of flowers was $4.13{\sim}4.28$, which was decreased to $3.40{\sim}3.49$ with maturing. The total acid was steadily increased for 26 days and then decreased thereafter. Vitamin C, not detected until 14 days, was gradually increased to $15.83{\sim}24.90mg%$ in 34 days. Reducing sugar content was increased for 24 days and then decreased, while total sugar, glucose and fructose were generally increased during maturing. Xylose was detected a little. For minerals, potassium was measured the highest value, followed by magnessium, and sodium. A trace amount of manganese, zinc and copper were detected. The strawberries had the content range of $6.00{\sim}24.60mg%$ of methyl alcohol and $6.00{\sim}24.40mg%$ of ethyl alcohol.

• Korean Journal of Materials Research
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• v.27 no.4
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• pp.199-205
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• 2017

In this study, (3,4-epoxycyclohexane)methyl 3,4-epoxycyclohexylcarboxylate acrylate was synthesized by reacting (3,4-epoxycyclohexane)methyl 3,4-epoxycyclohexylcarboxylate with acrylic acid to minimize hardening shrinkage and to improve heat resistance, which are known as disadvantages of photopolymers for 3D printing application. Urethane acrylate was synthesized by reacting 1,3,5-triazine-2,4,6-triamino alcohol, 2-hexylethyl acrylate, and isophorone diisocyanate in order to improve the mechanical properties without deteriorating the heat resistance. The physical properties before and after the synthesis of the acrylate and the mechanical properties when the urethane acrylate was applied were investigated. The reaction progress of the composite was examined by FTIR and $^{13}C$ NMR. The heat deflection temperature, flexural strength, and surface hardness of the molding were measured. The curing behavior by Photo-DSC ultraviolet irradiation was also examined.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.151-158
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• 1997

Burley leaf tobacco extracts has been heated at loot for 2 hours and changes in non-volatile fructosazines and volatile components were investigated. Major changes for the heat treatment with corn syrup of burley leaf tobacco extracts were as follows, increases in the contents of 2,5-deoxyfructosazine and 2,5-fructosazine that is produce for the heating reaction of sugar and ammonia, production of pyraEine compounds, such as 2,6-dimethyl pyrazine,2,4-dimethyl pyrazine, ethrnyl pyrazine, methylethyl pyraxine, trimethyl pyrazine, 2-ethenyl-5-methyl pyrazine, 2-acetyl parazine and 2-acetyl-3-methyl pyrazine, increases in the content of furfuryl alcohol derived from sugar degrad ation, production of 2,5-dimethyl-4-hydroxy-3(2H)-furanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one derived from thermal degradation of Amadori compounds.

• Journal of the Korean Society of Safety
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• v.11 no.3
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• pp.137-142
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• 1996

Combustion characteristics of immobilized methyl, ethyl and propyl alcohols on sands were studied. Experiments were performed by burning methyl, ethyl and propyl alcohols Immobilized on sands (particle size 0.1~5mm) and ceramic balls(particle size 5mm) to measure mass burning rate, height burning rate and combustion temperature. It was concluded that the longer time from ignition to extinguishment was resulted from the larger particle size of sands and the smaller size of sands exhibited the higher mass burning rate. Of alcohols tested the relative magnitude of facilitation of combustion was methyl>ethyl>propyl alcohol. Combustion temperature of alcohols, without regard to the types of alcohols, was not increased with smaller sands. However, with larger sands, combustion temperatare of alcohols was increased with the larger particle.

• Preventive Nutrition and Food Science
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• v.3 no.3
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• pp.230-233
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• 1998

Acetic acid producing bacteria were isolated from deastringent persimmon vinegar and the major bacterium was identified using morphological and biochemical tests. Acetobacter sp. AH-1 was motile, gram negative rod with catalase positive and oxidase negative. The strain can grow up to 5 % ethanol and 2% NaCl as well as 25% glucose. Optimum temperature and pH for growth were 3$0^{\circ}C$ and 5.0, respectively. Volatile constituents of persimmon vinegar were analyzed by purge and trap sampling . Acetic acid adn alcohol were the largest volatile compounds quantitiatively in persimmon vinegar. Among alcohols, 20methyl-1-propanol, isoamyl alcohol and amyl alcohol were detected. Isovaleradehyde and benzaldehyde for aldehyde, isoamyl acteate, ethyl formate, propyl aceetate, and ethyl acetate for esters were likely to contribute to persimmon vivegar flavor.