• Journal of Energy Engineering
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• v.13 no.3
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• pp.228-233
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• 2004

This paper reports production of low-molecular weight carboxylic acids from the hydrothermal treatment of representative organic wastes and compounds with or without oxidant (H$_2$O$_2$). Organic acids such as acetic, formic, succinic and lactic acids were obtained. This result increased to 42mg/g dry waste fish entrails in the presence of H$_2$O$_2$. Experiments on glucose representing cellulosic wastes were also carried out, getting acetic acid of about 29mg/g glucose. Studies on temperature dependance of formation of organic acids showed thermal stability of acetic acid, whereas, formic acid decomposed readily under hydrothermal conditions. In general. results demonstrated that the presence of oxidants favored formation of organic acids with acetic acid being the major product.

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.575-579
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• 2013

1,3-Propandiol is a promising chemical which can be produced from fermentation of glycerol because the application of 1,3-propanediol is mainly in the production of bio-polytrimethylene terephthalate (bio-PTT). However, the cost of downstream processes in the biological production of 1,3-propanediol can make a high portion in the total production cost due to the large amount of water and the by-produced carboxylic acids such as succinic, lactic and acetic acids in 1,3-propanediol fermentation broth. In this study, aqueous two-phases systems composed of hydrophilic alcohols and phosphate salts were applied to the recovery of 1,3-propanediol from its artificial aqueous solution. Formation of aqueous biphases in hydrophilic alcohols and phosphate salts was due to the salting-out effect of salts in bottom phase, thereby 1,3-propanediol in bottom phase was moved into top phase. Extraction efficiency for 1,3-propanediol was proportional to the polarity of hydrophilic alcohols and the basicity of salts and the maximum value of extraction efficiency was more than 98%. In the aqueous two-phases systems after extraction, there was no carboxylic acid in top phase. Therefore, it was concluded that the aqueous two-phases systems composed of hydrophilic alcohols and phosphate salts were effective for the selective recovery of 1,3-propanediol without any coextraction of carboxylic acids.

• Mass Spectrometry Letters
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• v.11 no.4
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• pp.103-107
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• 2020

We report the application of 2,4,6-trichlorobenzoyl chloride (often referred to as Yamaguchi esterification reagent) for the selective derivatization of the carboxylic group for GC-MS with the sample preparation method optimized for GC-MS analysis. The reagent was shown to be capable of selectively turning the carboxylic group into a reaction center, i.e., anhydride, of which the further reaction was directed to a near complete formation of required esters by unique steric and electronic effects of the reagent. Using the developed method, the chiral separation of hydroxycarboxylic acids by GC-MS using non-chiral columns was successfully demonstrated.

• Journal of the Korean Chemical Society
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• v.37 no.10
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• pp.903-909
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• 1993

Reaction mechanism of palladium(0, II)-phosphines complexes catalyzed cyclocarbonylation for unsaturated carboxylic acid such as crotonic acid, methacrylic acid and 3-butenoic acid has been investigated by product analysis, molecular mechanics and extended Huckel molecular orbital method. Reaction of 3-butenoic acid with palladium(0, II)-phosphines catalyst gives palladium containing cycloester through intermediate palladium-olefin ${\pi}$ -complex in the catalytic carbonylation. Palladium(0, II)-phosphines complexes catalyze the cyclocarbonylation of 3-butenoic acid to give 3-methylsuccinic anhydride and glutaric anhydride. But ${\pi}$ -complexes with palladium(0, II)-phosphines and unsaturated carboxylic acids such as crotonic acid and methacrylic acid are not effective the catalytic cyclocarbonylation.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.104-105
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• 1994

• Bulletin of the Korean Chemical Society
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• v.21 no.1
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• pp.141-144
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• 2000

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.730-732
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• 1998

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.469-470
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• 1995

• YAKHAK HOEJI
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• v.27 no.4
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• pp.289-293
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• 1983

Twelve new N-piperoyl amino acids were synthesized by acylation of amino acids with piperoylchloride in order to develop the new central nervous depressants. Silylation of the carboxylic group of amino acids not only precluded side reactions but-also facilitated acylation at room temperature without catalysts. The acute toxicity of all the synthesized compounds were lower than that of piperine itself, whereas they showed strong protective effect against the strychnine-induced mortality.

• Journal of the Korean Electrochemical Society
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• v.16 no.2
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• pp.74-80
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• 2013

We investigate the formation of nanoporous gold (NPG) surfaces by anodization in three carboxylic acid (formic acid, acetic acid, and propionic acid) solutions and the electrochemical oxidation of glucose at NPG surfaces. Among three carboxylic acids, formic acid provided the most efficient conditions for NPG formation towards glucose oxidation. The optimized conditions during anodization in formic acid for glucose oxidation were 5.0 V of applied potential and 4 hour of reaction time. Electrocatalytic activities for glucose oxidation at NPG surfaces prepared by anodization in carboxylic acids were examined under the absence and presence of chloride ions, which were compared to those observed at NPG prepared in oxalic acid solutions. The application NPG prepared by optimized anodization conditions in formic acid to the amperometric detection of glucose was demonstrated.