• Fire Science and Engineering
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• v.29 no.6
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• pp.45-50
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• 2015

The flash point is one of the most important properties for characterizing the fire and explosion hazard of liquid solutions. In this study, a Tag open-cup apparatus was used to measure the flash points of two flammable binary mixtures, n-decane + n-octanol and acetic acid + n-butanol. The flash point temperature was estimated using the UNIFAC (Universal Functional Activity Coefficient) group contribution model and optimization method. The experimentally derived flash point was also compared with the predicted flash point. The two methods can estimate the flash point fairly well for the n-decane + n-octanol and acetic acid + n-butanol systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.181-184
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• 2003

We investigated the effect of ethanol on the production of cellulose and acetic acid fermentation by Gluconacetobacter persimmonensis KJ145. Results showed that bacterial cellulose productivity was highest when 2% ethyl alcohol was added to apple-juice medium. For acetic acid production, 7% ethyl alcohol was needed. Optimal concentration of ethyl alcohol was 5% for simultaneous production of bacterial cellulose and acetic acid. For simultaneous production of bacterial cellulose and acetic acid, optimal nitrogen source and optimal concentration were corn steep liquor and 15% (w/v), respectively Optimal culture time for simultaneous production of bacterial cellulose and acetic acid was 14 days. At the optimal condition, Cluconacetobacter persimmonenis KJ145 produced 7.55 g/L of bacterial cellulose (dry weight).

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.407-410
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• 1992

Changes in the concentrations of six low-molecular-weight organic acids extracted from hydrolysates of plant residues undergoing decomposition for 90 days under the laboratory condition were investigated. 1. Litters of deciduous and coniferous trees and wild grass cuttings were sampled for the study and concentrations of formic, acetic, succinic, tartaric, malic and citric acids were determined. The concentration of malic acid were negligible. 2. In the wild grass cuttings, the total concentration of low-molecular-weight organic acids decreased with the passage of decomposition. Monocarboxylic acids, I. e., formic and acetic acids, predominated over dicarboxylic and tricarboxylic acids. Formic and acetic acids appeared to be compensatory for each other. Concentration of citric acid increased at a remarkable rate. 3. The total concentration of organic acids in the hydrolysates of deciduous litter was shown to increase. The concentration of monocarboxylic acids was significantly higher in the end of the period of decomposition. Here again a compensatory relationship was observed between concentrations of formic and acetic acids. 4. There was comparatively little change exhibited during the period of experiment concerning the concentrations of organic acids from hydrolysates of decomposing coniferous litter. In contrast with the others, however, the concentration of succinic acid, a dicarboxylic acid, maintained the highest level.

• Food Science and Preservation
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• v.23 no.3
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• pp.347-354
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• 2016

To investigate the effect of different acetic acid bacteria on qualities of detoxified Rhus verniciflua vinegar (DRV), different DRVs were produced by using three acetic acid bacterial strains including Acetobacter pasteurianus KACC16934 (AP), Acetobacter malorum V5-7 (AM), and Gluconoacetobacter entanii RDAF-S (GE). Little difference in pH (2.87~2.90) or titratable acidity (5.33~5.68%) was observed among different DRVs. Acetic acid yields of the AP, AM, and GE strains were 78.6%, 85.3%, and 85.9%, respectively. Organic acid content in different DRVs was in the range of 69.84~73.83 mg/mL. Oxalic acid, malic acid, succinic acid, acetic acid, and fumaric acid were detected in all DRVs. And glutamic acid, alanine, valine, leucine, tyrosine, lysine, anserine, and arginine were detected in all DRVs. Arginine and alanine were the predominant amino acids in all DRVs. PCA plots of electronic nose analysis data showed a significant differentiation of DRVs from different acetic acid bacterial strains. A sensory evaluation of all DRVs indicated that DRV fermented using AM was superior in the aspect of flavor, tasted and overall preference.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.3
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• pp.642-650
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• 2006

As an effective non-pharmacological method of pain relief, hydrotherapy was widely used. And bath additive has been used for enhancing the efficacy of hydrotherapy, In the present study, as a bath additive, the analgesic activity of HAC, which composed of Corydalis turtschaninovii, Atractylodes japonica, and Harpagophytum procumbens(HAC), was investigated in the ventrolateral periaqueductal gray (VIPAG), lateral PAG (IPAG), central nuclei of amygdala (CeA), and the paraventricular nucleus of the hypothalamus (PVN) in mice, using writhing test and immunohistochemistry for c-Fos. Male C57BU6 mice weighing $25{\;}{\pm}{\;}2g$ (8 weeks of age) were used for this experiment. The animals were divided into five groups: the control group, the acetic acid treatment group, the acetic acid treatment and 0.01 g/L HAC-immersed group, the acetic acid treatment and 0.1 g/L HAC-immersed group, and the acetic acid treatment and 1.0 g/L HAC-immersed group. To induce somato-visceral pain in the experimental animals, a single intraperitoneal (i.p.) injection of acetic acid was administrated to each animal, and the animals of the control group received injections of equivalent doses of normal saline. The animals of the HAC-immersed groups were immersed the water with HAC powder at the respective doses deep enough to cover the mice body, and those of the control group and the acetic acid treatment group immersed the water without HAC powder at 10 min immediately after the acetic acid injection. Our present study has shown that the HAC reduced the acetic acid-induced abdominal constrictions and the acetic acid-Induced increase of numbers of c-Fos-positive cells in the VIPAG, IPAG, PVN, and CeA. The most potent analgesic effect appeared with the treatment of 1.0 g/L KB-immersed group. Based on our present results, it is very possible that HAC can be a potent therapeutic bath additive for alleviating pain without the fear of addiction to the drugs and side-effects associated with the prescription of multiple analgesic drugs.

• Journal of Environmental Science International
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• v.32 no.3
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• pp.191-195
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• 2023

This study aimed to investigate the effect of amino acid additives to weaned piglet diets on the pH and volatile fatty acids of pig slurries. A total of 135 weaned 22 -day-old piglets (Yorkshire x Landrace x Duroc) were used in this 56-d study. The three dietary treatments were as follows: (1) Control as a basal diet, (2) 1% amino acid additive and (3) 2% amino acid additive. Both pH and acetic acid values at 71 and 78 days were significantly different in all treatment groups (p<0.05). In addition, significant differences in propionic acid values were observed among treatment groups at 64 and 78 days (p<0.05). However, pH, acetic acid, and propionic acid values did not differ between 1% and 2% amino acid treatment groups. In conclusion, adding 1% and 2% amino acid to weaned piglet diets reduced the pH, acetic acid and propionic acid contents of pig slurries by acting as a probiotic. This may help formulate increase management strategies for improving the pig housing environment.

• Food Science and Preservation
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• v.17 no.5
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• pp.733-740
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• 2010

Brown rice vinegars were prepared by agitated or static acetic acid fermentation using different yeast strains (Saccharomyces kluyveri DJ97, Saccharomyces cerevisiae JK99, Saccharomyces cerevisiae GRJ, or Saccharomyces cerevisiae H9). Organic acid contents and levels of volatile compounds were compared in vinegars prepared by different methods. The chosen yeast strain did not significantly affect the organic acid content of vinegar. In vinegars prepared by agitated acetic acid fermentation, organic acid contents were, in the order of descending abundance, acetic acid, citric acid, lactic acid, oxalic acid, and tartaric acid. In vinegars prepared by static acetic acid fermentation, no citric acid was detected, and lactic acid content was higher than that in agitated acetic acid fermented vinegar. The volatile compounds of both vinegars, analyzed by GC-MS, did not significantly differ when various yeast strains were used. Eighteen volatile compounds were detected in vinegar prepared by agitated acetic acid fermentation and 11 in vinegar prepared by static fermentation. Volatile compounds that can affect vinegar quality, including ethyl acetate and phenethyl acetate, were present at high concentrations in static acetic acid fermented vinegar. Electronic nose analysis showed that volatile chemical patterns differed between the two types of vinegar, but there were no significant differences in sensory scores between vinegars prepared using various yeast strains or by either of the two methods of fermentation.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.1043-1047
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• 2009

Three experiments were conducted to determine the conversion rate of formic and acetic acids into methane in the gastrointestinal tracts of geese. In experiment I, two sets of two 4-month-old male White Roman geese were allocated to one of two treatment groups. Each set of geese was inoculated either with formic acid or with phosphate buffer solution (PBS). After the acid or the PBS was inoculated into the esophagi of the geese, two birds from each treatment were placed in a respiratory chamber as a measurement unit for 4 h in order to determine methane production rate. In experiment II and III, 6- and 7-wk-old male White Roman goslings were used, respectively. Birds were allocated to receive either formic acid or PBS solution injected into the ceca in experiment II. Acetic acid or PBS solution injected into the cecum were used for experiment III. After either the acids or the PBS solution were injected into the cecum, two birds from each treatment were placed in a respiratory chamber as a measurement unit for 3 h; each treatment was repeated 3 times. The results indicated that formic acid inoculated into the oesophagi of geese was quickly converted into methane. Compared with the PBS-injected group, methane production increased by 5.02 times in the formic acid injected group (4.32 vs. 0.86 mg/kg BW/d; p<0.05). Acetic acid injected into the ceca did not increase methane production; conversely, it tended to decrease methane production. The present study suggests that formic acid may be converted to methane in the ceca, and that acetic acid may not be a precursor of methane in the ceca of geese.

• Korean Chemical Engineering Research
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• v.54 no.6
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• pp.753-761
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• 2016

Liquid-liquid extraction (LLE) can be used for the recovery of acetic acid from black liquor prior to bioethanol fermentation. Recovery of value-added chemicals such as acetic-, formic- and lactic acid using LLE from Kraft black liquor was studied. Acetic acid and formic acid have been reported to be strong inhibitors in fermentation. The study elucidates the effect of three reaction parameters: pH (0.5~3.5), temperature ($25{\sim}65^{\circ}C$), and reaction time (24~48 min). Extraction performance using tri-n-octylphosphine oxide as the extractant was evaluated. The maximum acetic acid concentration achieved from hydrolyzates was 69.87% at $25^{\circ}C$, pH= 0.5, and 36 min. Factorial design was used to study the effects of pH, temperature, and reaction time on the maximum inhibitor extraction yield after LLE. The maximum potential extraction yield of acetic acid was 70.4% at $25.8^{\circ}C$, pH=0.6 and 37.2 min residence time.

• Membrane Journal
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• v.6 no.4
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• pp.227-235
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• 1996

poly(acrylic acid)(PAA)-poly(vinyl alcohol)(PVA) membranes have been prepared by crosslinking reaction between the carboxylic acid groups of PAA and the hydroxylic groups of PVA. In the measurements of the swelling and preferential sorption of the membranes, sorption behaviors of the membranes in pure water, pure acetic acid and a mixture of them have been investigated, respectively. From the measurements of the preferential sorption in 90wt% acetic acid of aqueous mixture, the sorption of water component was found to be more enhanced at high PAA content in the membrane than that of acetic acid component due to the interaction of water with acetic acid. The sorption behavior and the degree of crosslinking influenced competitively the permeation behavior of permeants. Permeation behavior of perrecants through the membranes was analyzed by using permeation activation energies which had been obtained from the Arrhenius plots of fluxes.