• Animal Bioscience
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• v.34 no.2
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• pp.223-232
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• 2021

Objective: To investigate the improvement in utilization efficiency of total mixed ration (TMR) on Tibetan plateau, TMR were ensiled with different additives. Methods: A total of 150 experimental silos were prepared in a completely randomized design to evaluate the six treatments: i) control (without additive), ii) Lactobacillus buchneri (L. buchneri), iii) acetic acid, iv) propionic acid, v) 1,2-propanediol; and vi) 1-propanol. After 90 days of ensiling, silos were opened for fermentation quality and in vitro analysis, and then subjected to an aerobic stability test for 14 days. Results: Treating with L. buchneri, acetic acid, 1,2-propanediol and 1-propanol decreased propionic acid contents and yeast number, whereas increased (p<0.05) pH, acetic acid and ethanol contents in the fermented TMR. Despite increased dry matter (DM) loss in the TMRs treated with 1,2-propanediol and 1-pronanol, additives did not affect (p>0.05) all in vitro parameters including gas production at 24 h (GP24), GP rate constant, potential GP, in vitro DM digestibility and in vitro neutral detergent fibre digestibility. All additives improved the aerobic stability of ensiled TMR to different extents. Specially, aerobic stability of the ensiled TMR were substantially improved by L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol, indicated by stable pH and lactic acid content during the aerobic stability test. Conclusion: L. buchneri, acetic acid, 1,2-propanediol, and 1-propanol had no adverse effect on in vitro digestibility, while ensiling TMR with the additives produced more acetic acid and ethanol, subsequently resulting in improvement of aerobic stability. There is a potential for some fermentation boosting additives to enhance aerobic stability of fermented TMR on Tibetan plateau.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.446-451
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• 2003

인화점은 가연성 액체의 화재 위험성을 나타내는 지표로써, 가연성액체의 액면 가까이서 인화할 때 필요한 증기를 발산하는 액체의 최저온도로 정의한다. 인화점에는 하부인화점과 상부인화점으로 나누고 있으며, 일반적으로 하부인화점을 인화점이라 한다.(중략)

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.173.3-173
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• 2003

No Abstract, See Full Text

• KSBB Journal
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• v.23 no.4
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• pp.340-344
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• 2008

Coprinus cinereus peroxidase (CiP) was often used as a catalyst for oxidative polymerization of a variety of phenol derivatives to produce a new class of polyphenols. Economical point of view, to know the mechanism of enzyme deactivation is significantly important because cost of enzyme is critically high. Hydrogen peroxide being used as oxidizing agent induced deactivation of peroxidase by destruction of heme structure. In the presence of hydrogen peroxide the stability of peroxidase was unexpectedly improved by adding organic solvent. Especially 2-propanol significantly improved enzyme stability among tested solvents. Radical scavenging by organic solvents may play a major role in protecting peroxidase from the oxidation of oxidizing radicals.

• Membrane Journal
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• v.14 no.4
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• pp.275-288
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• 2004

Carbon dioxide was absorbed into water-in-oil (w/o) emulsion composed of aqueous 2-amino-2-methyl-1-propanol (AMP) droplets as a dispersed phase and benzene solutions of polybutene and polyisobutylene as a continuous phase in a flat-stirred vessel to investigate the effect of non-Newtonian rheological behavior on the rate of chemical absorption of $CO_2$, where the reaction between $CO_2$ and AMP in the aqueous phase was assumed to be a pseudo-first-order reaction. It was expressed that PIB with elastic property made the rate of chemical absorption of $CO_2$ accelerated by comparison of mass transfer coefficient of $CO_2$ in the non-Newtonian liquid with that in the Newtonian liquid.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.5
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• pp.507-513
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• 2005

Increasing amounts of anthropogenic $CO_2$ emitted to the atmosphere are believed to be a significant factor in global climate change. Hence, the method of chemical absorption has been suggested to separate and recover acid gases such as $CO_2$. In this study, the characteristics of absorption and regeneration of $CO_2$ for the absorbent which adding HMDA (hexamethylenediamine) into AMP (2-amino-2-methyl-1-propanol), hindered amine, was investigated in lab-scale absorption/regeneration reactor. As a result of this study, the removal efficiency of $CO_2$ increased when adding $5.9\%,\;11.7\%\;and\;23.4\%$ HMDA into $30\%$ AMP respectively. Also, the removal efficiency of $CO_2$ increased $6.5\%,\;8.4\%,\;10.3\%$ respectively as compared to AMP alone when the gas flow rate was 7.5 SL/min. In addition, all absorbents used in the study revealed the high stripping efficiency, which was almost $99\%$, at the temperature of $110^{\circ}C$. Thus, the regeneration tower should be operated at $110^{\circ}C$. At this time, the concentration of exhausted $CO_2$ was higher than $99\%$.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.236-245
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• 1999

Andong Soju is a Korean traditional distilled liquor brewed with Nuruk which is cultured with wild microorganisms. To provide useful information for scientific production and systematic quality control of traditional distilled liquor, the effects of mixed culture of the alcoholic yeasts and saccharifying molds isolated from the Nuruk, and mashes on the flavor and sensory characteristics were investigated. Distillate from mashes cocultured with Saccharomyces cerevisiae and Hansenula anomala using Mucor Nuruk was compared with distillate from mashes brewed with Andong Nuruk and with distillate from plant fermented mashes to analyze their flavor characteristics. The volatile flavor compounds in distillates were analyzed by GC and GC-MS using direct injection, solvent extraction, and purge & trap methods. Alcohols such as 3-methyl-1-butanol, 2-methyl-1-propanol, 1-propanol, and 2-phenyl ethanol; aldehydes such as acetaldehyde and 2-furancar-boxaldehyde; esters such as ethyl ester of acetic acid, hexanoic acid, octanoic acid, decanoic acid; alkanes, alkenes, ketone, sulfur, and pyrone compounds were detected. Alcohols were chief components of flavor compounds. No significant difference in overall acceptability test was shown among three experimental groups(p<0.05), but Nuruk-like aroma, Kaoliangchiew-like aroma, sweet taste, and well rounded mouthfeel showed significant differences among them(p<0.05).

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.6
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• pp.605-612
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• 2005

In this study, the possible use of HMDA (Hexamethylenediamine) as additive to enhance reaction between $CO_{2}$ and AMP (2-amino-2-methyl-1-propanol) which has higher absorption capacity than that of MEA (Monoethanolamine) was investigated. Also, the absorption capacity for $CO_{2}$ was compared with addition of HMDA, piperazine or MDEA (N-methyldiethanolamine) into $30\;wt\%$ AMP at $40^{circ}C$ and $CO_{2}$ partial pressure ranging from 0.5 to 120 kPa. Apparent rate constant ($K_{app}$) and absorption capacity with the addition of $5\∼20\;wt\%$ HMDA into AMP increased $214.2\∼276.3\%$ and $29.9\∼91.7\%$ than those of AMP alone. As a result, when $5\;wt\%$ HMDA added into AMP, the increasing rate of the absorption rate and the absorption capacity was found to be the highest. In addition, the absorption capacity increased $6.8\%,\;9.8\%,\;11.6\%$ with addition of MDEA, piperazine or HMDA respectively as compared to AMP alone at $CO_{2}$ partial pressure of 20 kPa. Consequently, HMDA as additive to improve absorption capacity of AMP was superior to other additives.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3280-3288
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• 2014

Alkoxyalcohols are used as solvents or preservatives in various consumer products such as wet wipes. The metabolites of alkoxyalcohols are known to be chronically toxic and carcinogenic to animals. Thus, an analytical method is needed to monitor alkoxyalcohols in wet wipes. The aim of this study was to develop a simultaneous analytical method for 14 alkoxyalcohols using headspace gas chromatography coupled with mass spectrometry to analyze the wet wipes. This method was developed by comparing with various headspace extraction parameters. The linear calibration curves were obtained for the method ($r^2$ > 0.995). The limit of detection of alkoxyalcohols ranged from 2 to $200ng\;mL^{-1}$. The precision of the determinative method was less than 18.20% coefficient of variation both intra and inter days. The accuracy of the method ranged from 82.86% to 119.83%. (2-Methoxymethylethoxy)propanol, 2-phenoxyethanol, and 1-phenoxy-2-propanol were mainly detected in wet wipes.

• Journal of Environmental Health Sciences
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• v.39 no.6
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• pp.483-491
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• 2013

Objectives: Electronic cigarettes are battery powered devices that convert a nicotine-containing liquid into an inhalable vapor. The device aerosolizes nicotine so that it is readily entrained into the respiratory tract, from where it enters the bloodstream. Information on the safety of E-cigarettes is required. Methods: Seventeen articles on studies analyzing toxic substances in the liquid and gas phases of electronic cigarettes were reviewed. Results: Tobacco-specific nitrosamines, bis(2-ethylhexyl) phthalate, formaldehyde and acetaldehyde, known to be carcinogenic agents in humans or animals, were detected in the liquid and gas phases. In addition, diethyl phthalate, acetone, ethanol, cresol, xylene, propylene, styrene, triethylene glycol, tetraethylene glycol, pentaethylene glycol cis-3-hexen-1-ol, methyl cinnamate and undecane were identified in the liquid and gas phases of E-cigarettes. Propylene glycol, glycerin, 1-methoxy-2-propanol, 1-hydroxy-2- propanone, acetic acid, 1-menthone, 2,3-butanediol, menthol, carvone, maple lactone, benzyl alcohol, 2-methyl-2-pentanoic acid, ethyl mantel, ethyl cinnamate, myosamine, benzoic acid, 2,3-bipyridine, cotinine, hexadecanoic acid, and 1'1-oxybis-2-propanol were detected in the vapors of E-cigarettes. Conclusion: The hazardous compounds identified in the liquid and gas phases of E-cigarettes should be controlled for the lowest concentrations in the raw materials and production procedures.