• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.202-205
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• 2005

The effects of ligands on reactivity under GoAgg oxidation system have been studied. Picolinic acid containing carboxylic acid showed the most excellent activity among various ligands. Also, Picolinic acid of ortho position carboxylic group in pyridine ring largely increased reaction rates in the GoAgg oxidation systems. From these results, we proposed the new mechanism on the GoAgg oxidation using ligands having carboxylic group at ortho position.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.63-63
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• 2007

Carboxylated multi-walled carbon nanotubes (MWNTs) were in detail characterized by XRD, XPS, FTIR, and thermogravimetric measurements. Carboxylic acid groups were functionalized to MWNTs using aqueous acid solutions. The change. of sonication and reflux conditions rarely influenced the degree of carboxylation on MWNTs, but reduced the thermal stability of the resulting carboxylated MWNTs. The characteristic Bragg peaks of pristine and carboxylated MWNTs were analyzed by XRD measurements. After acid treatment the diffraction peaks (100), (101), and (102) of pristine MWNTs disappeared, but the diffraction peak (002) was preserved in the carboxylated MWNTs. The introduction of carboxylic acid groups on MWNTs caused to improve the dispersibility of the resulting carboxylated MWNTs in water.

• Journal of the Korean Chemical Society
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• v.15 no.2
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• pp.65-68
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• 1971

The possibility of the two-phase oxidation of an aldehyde to carboxylic acid was studied. Thus the ether solutions of representative aldehydes (2.0M) were treated with 1.5 mole equivalent of chromic acid solution (1.0M) for 30 minutes at room temperature. Of the ten aldehydes tested,m butanal, benzaldehyde, tolualdehyde, o-, m-, p-nitrobenzaldehyde and cinnamaldehyde could be oxidized conveniently to the corresponding carboxylic acid giving an 80-90% yield. But furfural gave only a 30% yield of furoic acid and the oxidation of salicylaldehyde was unsuccessful.

• Journal of the Korean Applied Science and Technology
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• v.22 no.3
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• pp.219-227
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• 2005

Competitive solvent extraction of the mixure of alkali metal and alkaline earth cation from water into organic solvent containing the crown ether carboxylic acid and anlogous crown ether phosphonic acid was investigated as follows. The lipophilic group is found to strongly influence to the selective extraction in the mixed systems from only alkali metal cation for sym-(n-decyldibenzo)-16-crown-5-oxyacetic acid $\underline{1}$ to mostly alkaline earth metal cation for sym-bis[4(5)-tert-butylbenzo]-16-crown-5-oxyacetic acid $\underline{3}$. Monoethyl sym-(n-decyldibenzo)-16-crown-5-oxymethylphosphonic acid $\underline{2}$. and monoethyl-sym- bis]4(5)-tert-butylbenzo]-16-crown-5-oxymethylphosphonic acid $\underline{4}$ showed good selectivity for $Na^+$ over $Mg^{2+}$, the second extracted ion. Structural variation in the crown ether phosphonic acid somewhat was influenced to the extraction selectivity in the mixed systems. when variation of the ionized group is influenced in the mixed systems, the selectivity of $Na^+$ as the second extracted ion was much better crown ether carboxylic acid $\underline{1}$ than crown ether phosphonic acid $\underline{2}$, while the efficiency of $Na^+$ extraction was better $\underline{2}$ (83% total loading) than $\underline{1}$ (32%).

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1085-1087
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• 2004

• YAKHAK HOEJI
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• v.7 no.1
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• pp.8-12
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• 1963

The piperazine salts with 24 kinds of phenols and 6 kinds of organic carboxylic acids were prepared. The test of anthelmintic effect against Ascaris suilla, in vitro, for Hexachlorophene-piperazine salt, Bithionol-piperazine salt, Kainic acid-piperazine salt were also carried out compared with piperazine, Hexachlorophene, Bithionol and Kainic acid.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.547-551
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• 1989

1-Methoxypyrrole-2-carboxylic acid and its derivatives were prepared. Fridel-Crafts bromination occurs first at 4-position and then at 5-position. Acylation of 3-methyl derivative was also directed to 4-position.

• YAKHAK HOEJI
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• v.31 no.1
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• pp.14-18
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• 1987

2-Substituted-3, 4-dihydro-2H-1, 2-benzothiazin-4-one 1, 1-dioxide 6 was reatced with magnesium methyl carbonate to form magnesium chelate 7, which could be hydrolized in cold hydrochloric acid solution to give 2-substituted-4-hydroxy-2H, 1, 2-benzothiazine-3-Carboxylic acid 1, 1-dioxide 2 in good yield.

• YAKHAK HOEJI
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• v.10 no.2_3
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• pp.8-11
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• 1966

항인결핵균성및 streptomycin, isoniazid및 para-aminosalicylic acid에 대한 내성인결핵균주에 현저한 항균작용 있는 dextro-2,2'-(ethylenediimino)-di-1- butanol(Ethambutol) 계열 및 thioureido(-NHCSNH-) 함유화 합물 계열인 2,2'-(ethylenediimino)-di-1-butyric acid및 2,2'-(thioureido)-di-1-butyric acid를 합성했으며 이들 약물의 구조와 작용간의 상호관계를 설명코저 이들 화합물과 류사한 구조인 2,2'-(thioureido)-di-acetic acid를 합성했기에 보고함.

• The Microorganisms and Industry
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• v.13 no.1
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• pp.10-13
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• 1987

L-Azetidine-2-carboxylic acid(A-2-C) is a four-membered cyclic imino acid which was first discovered from Convalaria majalis and Polygonatum officinalis in 1955(1,2). The imino acid A-2-C has been identified in at least 16 species of plants (3) (mostly the families Liliaceae, Agavaceae and Amaryllidaceae); in two marine sponges (Haliclona sp. and Chalinospilla sp.) (4); in the red algae (Lophocladia lamenandi) (5); in the sugar beet Beta vulgaris (6) ; and the microorganism Actinoplanes ferrugineus (7).