• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.977-983
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• 2005

The removal characteristics of ethyl acetate and 2-butanol were investigated in a bench-scale down-flow biofilter packed with Jeju scoria medium. Various inlet concentrations and gas flow rates were tested. The adaptation times of microorganisms to the change of the influent concentration of ethyl acetate and 2-butanol gas were found to be about 3 days. At the inlet concentration of 300 ppmv and empty bed contact time (EBCT) of 15 see, the removal efficiencies of the biofilter for ethyl acetate and 2-butanol were above $99.9\%$. The maximum removal capacity of the biofilter for ethyl acetate was $316-318\;g/m^3/h$ and that for 2-butanol was $245-251\;g/m^3/h$. Overall, the removal capacity of the biofilter for ethyl acetate was $50-70\;g/m^3/h$ larger than that for 2-butanol. During the operation of 65 days, the pressure drop through the biofilter column was maintained below $13\;mmH_{2}O/m$. Although the pH in the drain water decreased from 7.2 to 5.0, the pH drop did not affect the removal of the gases. From the above results, the biofilter using Jeju scoria as a packing material seemed to very effectively treat waste gases such as ethyl acetate and 2-butanol.

• Applied Chemistry for Engineering
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• v.3 no.1
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• pp.119-129
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• 1992

The rates of mass transfer with the alkaline hydrolysis of ethyl acetate and n-butyl acetate were measured by using a modified Lewis cell. The rates of mass transfer with chemical reaction were independent of the speed of agitation, and the reaction enhancement factors were independent of the ionic strength. The second order reaction rate constants of ethyl acetate and n-butyl acetate could be obtained from an approximate solution of a diffusion equation by film theory, and their values were $0.041m^3/kg\;mol{\cdot}s$ and $0.338m^3/kgmol{\cdot}s$, respectively.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.849-853
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• 2002

Metal ions have an adverse effect on anaerobic digestion. In an acetate degradation test of upflow of anaerobic sludge blanket granules with $Cu^{2+}$, not all of the acetate that disappeared was stoichiometrically converted to methane. In the presence of 400 mg/g-VSS (volatile suspended solids) $Cu^{2+}$, only 26% of the acetate consumed was converted to methane. To study acetate conversion by other anaerobic microorganisms, sulfate and nitrate reductions were investigated in the presence of $Cu^{2+}$ Sulfate and nitrate reductions exhibited more resistance to $Cu^{2+}$than methanogenesis, and the granules reduced 2.2 mM and 5.4 mM of nitrate and sulfate, respectively, in the presence of 400 mg/g-VSS copper ion. However, the acetate degraded by sulfate and nitrate reductions was only 24% of the missing acetate that could have been stoichiometrically converted to $CO_2$. Accordingly, 76% of the acetate consumed appeared to have been converted to other unknown compounds.

• Textile Coloration and Finishing
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• v.8 no.4
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• pp.42-51
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• 1996

Alkaline hydrolysis to improve the hand of PET/acetate union fabric was studied in relation to skin saponification and retarding effect of salts on the alkaline hydrolysis of cellulose acetate fiber, accelerating effect of salts on the alkaline hydrolysis of PET fiber, and changes of total hand value(T.H.V) of PET/acetate union fabric treated with alkali/salt solution. It was found that the rate of saponification of acetate was delayed by the addition of salts such as LiCl, NaCl and CH$_{3}$COONa into NaOH solution below 10 minutes. The rate of shrinkage of acetate fabric treated with 5g/l NaOH solution at 9$0^{\circ}C$ and 60 minutes showed 20 % but it was decreased 8% by. the addition of 120g/l Concentration of inorganic salts. We could know that the rate of alkaline hydrolysis of filament yarn treated with alkali solution at 9$0^{\circ}C$ and 60 minutes was delayed about 3 % using 2,000T/M of hard twist yarn, especially acetate filament treated with alkali solution at 9$0^{\circ}C$ and 10 minutes was delayed about 10%. T.H.V. of PET/acetate union fabric was increased from 2.77 to 3.04~3.18 by the addition of salts into alkali solution.

• Food Science and Preservation
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• v.6 no.3
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• pp.333-338
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• 1999

This studies were conducted to investigate the effects of calcium lactate and calcium acetate on the duality and shelf-life of kimchi. Kimchi was prepared by adding 0.5% mixtures of calcium lactate and calcium acetate at ratios of 04:0, 0.4:0.1, 0.3:0.2. 0.2:0.3, 0.1:0.4, 0:0.5, and fermented at 10$^{\circ}C$. The shelf-life of the kimchi by adding the mixtures of calcium lactate and calcium acetate at the ratio of 0.4:0.1, 0.3:0.2, 0.2:0.1 can be extended approximately 5 days. And, calcium contents of the kimchi tissue increased 46 to 66% against the control products. And also, demage of parenchyma cell was lower, the scores of crispness and overall taste of the kimchi treated were higher than those of the control.

• Polymer(Korea)
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• v.33 no.3
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• pp.230-236
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• 2009

Water soluble vinyl acetate/alkyl methacrylate copolymers were prepared by the emulsion copolymerization of vinyl acetate and various methacrylates such as methyl methacrylate (MMA) and ethyl methacrylate (EMA). Potassium persulfate (KPS) and ammonium persulfate (APS) were used as an initiator. Poly (vinyl alcohol) (PVA) was used as a protective colloid. The drying characteristics of the prepared poly(vinyl acetate-co-methyl methacrylate) (PVAc/PMMA), poly(vinyl acetate-co-ethyl methacrylate) (PVAc/PEMA) were studied using moisture meter at the temperature between 100 and $200^{\circ}C$. The significant results are described as follows. The activation energy of the isothermal drying process of the copolymers has the order of PVAc/PMMA> PVAc/PEMA> PVAc.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.88-93
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• 1962

The telomerization of vinyl acetate with carbon tetrachloride, chloroform and monochlorobenzene were investigated with respect to the synthesis of those telomers, properties and molecular weights of the formed telomers, and reaction mechanisms. Vinyl acetate reacted with carbon tetrachloride and chloroform to form telomers at 70-90$^{\circ}C$ and 60-70$^{\circ}C$, respectively and it formed polymer with monochlorobenzene. As a chain transfer agent, carbon tetrachloride was more effective than chloroform. In the telomerization of vinyl acetate and carbon tetrachloride: 1) The average molecular weight of the telomer decreased as the mole ratio of carbon tetrachloride to vinyl acetate increased. The optimum conditions for the highest yield of the telomer were as follows: Mole ratio of carbon tetrachloride to vinyl acetate : 2.5 Reaction time : 20 hours. 2) As the reaction proceeded, the refractive index and average molecular weight of the telomer increased rapidly in the first 10 hours but the increase was slow through the next 10 hours, so that, the average recurring number(n) of taxogen in the final product reached an almost definite value, i.e., 3. The telomer formed in the telomerization of vinyl acetate with carbon tetrachloride and chloroform turned to brown color in the air due to decomposition or polymerization. The suggested telomerization mechanism was supported by the hexachloroethane detected in the course of reaction.

• Textile Coloration and Finishing
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• v.6 no.1
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• pp.8-18
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• 1994

In one bath dyeing system of silk/cellulose acetate fiber blend fabric with acid /disperse dyes, adsorption behavior of acid dyes and disperse dyes on silk and cellulose acetate fabrics were examined. In the dyeing of cellulose acetate with C. I. Disperse Red 19(Red 19) and C. I. Disperse Red 60(Red 60) at 8$0^{\circ}C$ and 10$0^{\circ}C$, dye uptake with Red 19 was higher than that with Red 60. When the silk/cellulose acetate dyed with Red 19 and Red 60 at 10$0^{\circ}C$, dye uptake on cellulose acetate was influenced by affinity of the dye to the silk fabric dyed together. When the silk/cellulose acetate dyed with Blue 80/Red 19 and Blue 80/Red 60 at 10$0^{\circ}C$, color of cellulose acetate dyed with Red 19 and Red 60 was not influenced by Blue 80 but silk dyed with Blue 80 was influenced by Red 19 and Red 60. Interrelation of K/S value and Munsell value was scarcely any but showed the change tendency of K/S value.

• Biomolecules & Therapeutics
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• v.11 no.2
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• pp.119-125
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• 2003

The present study was conducted to investigate the effects of bornyl acetate on arterial blood pressure and vascular contractile responses in the normotensive rats and to establish the mechanism of action. Both phenylephrine (an adrenergi$\alpha$-receptor agonist) and high potassium (a membrane-depolarizing agent) caused greatly contractile responses in the isolated aortic strips. These phenylephrine (10$^{-5}$ M)-induced contractile responses were depressed in the presence of high concentrations of bornyl acetate (10∼20 $\mu\textrm{g}$/ml), but not affected in low concentrations of bornyl acetate (2.5∼5$\mu\textrm{g}$/ml). High potassium (5.6 ${\times}$ 10$^{-2}$ M)-induced contractile responses were also greatly inhibited in the presence of bornyl acetate (2.5∼20 $\mu\textrm{g}$/ml) in a dose-dependent fashion. Bornyl acetate (1∼10 mg/kg) given into a femoral vein of the normotensive rat produced a dose-dependent depressor response, which is transient (data not shown). Interestingly, the infusion of a moderate dose of bornyl acetate (3mg/kg/30 min) made a significant reduction in pressor responses induced by intravenous norepinephrine. Collectively, these results obtained from the present study demonstrate that intravenous bornyl acetate causes a dose-dependent depressor action in the anesthetized rat at least partly through the blockade of adrenergic $\alpha$$_1$-receptors. bornyl acetate also causes vascular relaxation in the isolated aortic strips of the rat via the blockade of adrenergic $\alpha$$_1$-receptors, in addition to the unknown mechanism of direct vasorelaxation.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.823-827
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• 2004

Antimicrobial effect of Lithospermum erythrorhizon extracts against food-borne pathogens was investigated. L. erythrorhizon was extracted with methanol at room temperature, and the extraction was sequentially fractionated using petroleum ether, chloroform, ethyl acetate, and methanol. Antimicrobial activity of L. erythrorhizon extracts was determined using paper disc method against food-borne pathogens and food spoilage bacteria. Ethyl acetate extracts of L. erythrorhizon showed the highest activity against Staphylococcus aureus and Shigella dysenteriae. Synergistic effect was found in combined extracts of L. erythrorhizon and Sophora subprostrata as compared with each extract alone. Growth inhibition curve was determined using ethyl acetate extracts of L. erythrorhizon, against S. aureus and S. dysenteriae. Ethyl acetate extract of L. erythrorhizon, showed strong antimicrobial activity against S. aureus at 4,000 ppm, retarding growth of S. aureus more than 48 hr and S. dysenteriae up to 12 hr.