• Journal of Microbiology and Biotechnology
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• 제13권1호
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• pp.90-98
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• 2003

In vivo $^31p$ Nuclear Magnetic Resonance ($^31p$NMR) and metabolic studies were carried out on an acetic acid tolerant mutant, Zymomonas mobilis $ZM4/Ac^R$, and compared to those of the parent strain, Z. mobilis ZM4, to evaluate possible mechanisms of acetic acid resistance. This investigation was initiated to determine whether or not the mutant strain might be used as a suitable recombinant host far ethanol production from lignocellulose hydrolysates containing various inhibitory compounds. $ZM4/Ac^R$ showed multiple resistance to other lignocellulosic toxic compounds such as syringaldehyde, furfural, hydroxymethyl furfural, vanillin, and vanillic acid. The mutant strain was resistant to higher concentrations of ethanol or lower pH in the presence of sodium acetate, compared to ZM4 which showed more additive inhibition. in vivo $^31p$ NMR studies revealed that intracellular acidification and de-energization were two mechanisms by which acetic acid exerted its inhibitory effect. For $ZM4/Ac^R$, the internal pH and the energy status were less affected by sodium acetate compared to the parent strain. This resistance to pH change and de-energization caused by acetic acid is a possible explanation for the development of resistance by this strain.

• 한국안전학회지
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• 제32권2호
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• pp.66-71
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• 2017

The autoignition temperature (AIT) is crucial combustible characteristics which need attention in chemical process that handle hazardous materials. The AIT, also to as minimum spontaneous ignition temperature(MSIT), is the lowest temperature of a hot surface at which the substance will spontaneously ignite without any obvious sources of ignition such as a spark or flame. The AIT may be used as combustion property to specify operating, storage, and materials handling procedures for process safety. This study measured the AITs of n-propanol+acetic acid system from ignition delay time(time lag) by using ASTM E659 apparatus. The AITs of n-propanol and acetic acid which constituted binary system were $435^{\circ}C$ and $212^{\circ}C$, respectively. The experimental AITs of n-propanol+acetic acid system were a good agreement with the calculated AITs by the proposed equations with a few A.A.D.(average absolute deviation). In the case of n-propanol and acetic acid system, the minimum autoignition temperature behavior (MAITB), which is lower than the lower AIT, is shown among the two pure substances constituting the mixture.

• 한국미생물·생명공학회지
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• 제9권3호
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• pp.139-143
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• 1981

사과 식초 제조 과정 중 유기산의 변화를 검토하기 위하여 사과즙을 알콜발효시킨 후 Acetobacter aceti와 이 균에 NTG와 UV의 처리로 하여 얻은 변이주를 접종하여 식초산 발효를 시켰을 때 제조과정별로 유기산의 조성과 함량을 gas chromatography로 분석하여 다음의 결과를 얻었다. 1. 사과 원료 중 유기산의 함량은 malic acid 0.73 %, citric acid 0.038%, acetic acid 0.067%이었다. 2. 사과즙을 알콜발효시켰을 때 유기산의 함량은 malic acid 0.114%, lactic acid 0.1%, acetic acid 0.08%이었다. 3. 모균주와 변이주를 이용하여 얻어진 발효식초의 유기산 조성에 있어서는 차이가 없었고 함량에서는 차이가 있었다. 4. 변이주의 초기산 생성능은 모균주에 비하여 약간 빨랐다.

• 한국화재소방학회논문지
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• 제29권6호
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• pp.45-50
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• 2015

인화점은 액체 용액의 폭발과 화재의 위험성을 특징짓는 가장 중요한 성질 중 하나이다. 본 연구에서는 두개의 가연성 이성분계 혼합물인 n-decane + n-octanol계 및 acetic acid + n-butanol계의 인화점을 Tag 개방식 장치를 활용하여 측정하였다. 인화점은 그룹기여모델인 UNIFAC 식과, 최적화기법에 의해 계산되었다. 그리고 측정값과 비교하였다. 두 방법 모두 측정값을 잘 모사하였다.

• 한국식품영양과학회지
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• 제32권2호
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• pp.181-184
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• 2003

G. persimonensis-KJ145를 차용하여 BC 생산과 식초생산에 미치는 에탄올의 영향을 조사하였다. 그 결과 사과쥬스배지에 에탄올을 2%(v/v) 첨가하였을 때 BC의 생산성이 가장 좋았으며, 7%(v/v)를 첨가하였을 때 총산의 함량이 가장 높았다. BC와 식초를 동시 생산하기 위해서는 에탄올을 5%(v/v) 첨가하는 것이 가장 좋을 것으로 생각되며 발효과정 중의 식초 품질 변화에 대한 보다 자세한 연구가 요구되었다. BC와 식초 생산에 가장 효과적인 질소원은 CSL인 것으로 조사되었고 최적 농도는 15%(w/v)이었다. 배양시간의 영향을 조사한 결과 14일간 배양하는 것이 가장 많은 양의 BC를 생산하였으며, 최적조건에서 생산되는 BC 생산량은 7.55 g/L이었다.

• 한국식품영양과학회지
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• 제17권3호
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• pp.215-219
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• 1988

신선돈육의 등심부위를 절단하여 2% 초산용액을 분무하고 $4^{\circ}C$의 냉장고에 보관하면서 무처리구와 경시적으로 미생물학적, 이화학적, 육색의 변화등을 검토하여 저장성 증대의 가능성을 검토하였다. 초산용액의 분무는 신선육표면에 존재하는 aerobic bacteria 및 coliform bactereia의 생육억제에 상당한 효과가 있었다. pH, 단백질변패도(YBN), 지방산패도(TBA)의 측정치는 초산처리구가 대체로 낮게 나와 초산용액이 돈육의 부패를 지연시킬수 없음을 나타내었으며 이들의 값은 미생물의 생육변화와 유사한 양상을 나타내었다. 육색의 변화는 초산용액처리 직후에는 무처리구 보다 검게 나왔으나 저장 2일째 이후부터는 초산용액 처리구가 선홍색쪽에 가까왔다.

• Membrane and Water Treatment
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• 제8권4호
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• pp.323-336
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• 2017

The main challenge in many applications of acetic acid is acid dehydration and its recovery from wastewater streams. Therefore, the performance of polyamide thin film composite is evaluated to separate acetic acid from water. To reach this goal, the formation of polyamide layer on polysulfone support membrane was investigated via interfacial polymerization (IP) of meta-phenylenediamine (MPD) in water with trimesoyl chloride (TMC) in hexane. Also, the effect of synthesis conditions, such as concentration of monomers and curing temperature on separation of acetic acid from water were investigated by reverse osmosis process. Moreover, the separation mechanism was discussed. The solute permeation was carried out under applied pressure of 5 bar at $25^{\circ}C$. Surface properties of TFC membrane were characterized by ATR-FTIR, SEM and AFM. The performance test indicated that 3.5 wt% of MPD, 0.35 wt% of TMC and curing temperature of $75^{\circ}C$ are the optimum conditions. Moreover, the permeate flux was $4.3{\frac{L}{m^2\;h}}$ and acetic acid rejection was about 43% at these conditions.

• 대한임상독성학회지
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• 제16권2호
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• pp.161-164
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• 2018

The ingestion of corrosive substances often leads to severe morbidity and mortality. Acids produce coagulation necrosis with a lesser degree of penetration, whereas alkalis produce liquefactive necrosis with penetration. Acetic acid is a clear, colorless organic acid with a pungent, vinegar-like odor. The ingestion of highly concentrated acetic acid (glacial acetic acid) may cause a range of complications. On the other hand, perforation of the stomach is extremely rare but it has a high mortality rate. This paper reports a case of perforation of the stomach after the ingestion of glacial acetic acid with suicidal intent in an otherwise healthy 76-year-old woman.

• 한국식품위생안전성학회지
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• 제15권3호
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• pp.219-225
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• 2000

본 연구는 2.5-10% (w/v) trisodium phosphate (TSP) 및 0.5-2% (v/v)의 초산 용액에서 10분간 닭고기 (평균 500$\pm$30 g 중량) 다리의 표면을 침지한 다음 소매점(2$\pm$1。C) 및 4oC 냉장 동안 pH, thiobarbituric acid (TBA)가 및 육색에 미치는 영향을 분석한 결과이다. 2.5-10% TSP용액의 처리구는 처리 직후 대조구 보다 유의적으로 높은 pH 가를 나타내었으며 5-l0% TSP용액의 처리구는 저장 8일 까지 지속되었다 2.5-10%의 TSP용액의 처리구는 처리직후부터 저장 4일 까지 TBA가의 유의적 증가를 나타내었다. 0.5-2%초산용액의 처리구의 pH가는 처리직후 대조구보다 유의적 감소를 나타내었으며, 1.5-2%초산 처리구는 저장 16일 동안 지속되었다. 0.5-2%초산용액 처리구의 TBA가는 저장 4일 까지 대조구와 유의적 차이를 나타내었으며, 1.5-2%초산용액 처리구는 저장 8일 까지 지속되었다. 0.5-2%초산 용액 처리구의 Hunter color L$^+$ 가는 처리직후 대조구와 유의적 차이가 없었으며, 저장 4일과 12일에는 대조구와 유의적 차이를 나타내었다. 1-2%초산 용액 처리구의 Hunter color a$^+$가는 처리직후부터 저장 16일 동안 대조구와 유의적 차이가 있었다. 0.5-2%초산 용액 처리구의 Hunter color b$^+$ 가는 저장 4일에서 12일 동안 대조구와 유의적 차이가 없었었다.

• 동의생리병리학회지
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• 제20권3호
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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.