• Title/Summary/Keyword: acid gas

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The Corrosion Appearance of Mortar by The Sulfuric-Acid (황산에 의한 모르타르의 침식현상)

  • 이웅종;정연식;양승규;유재상;이종열
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.10a
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    • pp.43-48
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    • 2002
  • This study is experiment results that carried out the sulfuric acid immersion of the mortar containing blast furnace slag powder, based ell the mechanism of the sulfuric acid corrosion for concrete which was caused by the H$_2$S gas. The used materials is OPC, slag powder and gypsum, and the proportion of cement is total 13 levels which are 0~70% of the contents of slag, 0~6% of the contents of gypsum. The specimen is immersed by 5% H$_2$SO$_4$ solution after 28 days and its weight loss is measured at intervals of 7 days. The results of experiment showed that the substitution ratio of 70% slag was excellent at a point of view for the sulfuric acid resistance and the sulfuric acid resistance was not improved by tile increase of the blaine of slag(8, 000longrightarrow10, 000$\textrm{cm}^2$/g) and the addition of gypsum.

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Urinary Excretion of Triprolidine in Human (인체 뇨에서의 트리프로리딘 배설)

  • 정병화;엄기동;정봉철;박종세
    • Biomolecules & Therapeutics
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    • v.1 no.2
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    • pp.143-150
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    • 1993
  • The metabolic profile of triprolidine, 2-[(4-methylphenyl)-3-(1-pyrrolidinyl-1-propenyl)] pyridine, was determined. Urinary extracts obtained with enzyme hydrolysis were derivatized with MSTFA/TMSCl (N-methyl-N-trimethylsilyl trifluoroacetamide/trimethylchlorosilane) and analyzed by GC/MSD. In human urine, which were obtained after the oral administration with triprolidine, hydroxymethyltriprolidine, triprolidine carboxylic acid, oxotriprolidine carboxylic acid and unchanged triprolidine were detected. The maximum urinary excretion rate of triprolidine and hydroxymethyltriprolidine which were extracted from human urine was at 2 to 4 hours after the drug administration. Triprolidine and hydroxymethyl triprolidine were identified by comparison with authentic standards In chromatographic and mass spectral properties. Triprolidine carboxylic acid was detected as a major metabolite of its metabolites in the urine. Oxotriprolidine carboxylic acid and triprolidine carboxylic acid were tentatively identified by the interpretation of its mass spectral patterns. These data suggest that in human, hydroxylation of either the benzyl or pyrrolidine ring can occur during triprolidine elimination.

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Components in Commercial Douchi-a Chinese Fermented Black Bean Product by Supercritical Fluid Extraction

  • Kim, Joo-Shin;Chung, Hau-Yin
    • Preventive Nutrition and Food Science
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    • v.13 no.1
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    • pp.12-17
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    • 2008
  • Douchi, a popular seasoning agent in Chinese dishes prepared by the Aspergillus oryzae fermentation of black beans, was subjected to supercritical fluid extraction (SFE) and gas chromatography-mass spectrometry analysis for its volatile components. A total of 73 components were identified in two commercial brands, which were positively confirmed and quantified. Among the common components in the two brands were 18 acids, 12 alcohols, 11 aldehydes, 9 esters, 1 furan, 11 other oxygen-containing compounds, 4 pyrazines, 2 pyridines and 5 miscellaneous compounds. The most abundant components found were acetic acid, benzoic acid, 2,6-dimethylpyrazine, 2-piperidinone, 3-methylbutanoic acid, maltol, 4-ethylphenol, 2-methylpropanoic acid, butanoic acid, 2-pyrrolidinone, all fatty acids and some esters.

Synthesis and Thermal Stability of Polyol Esters (폴리올에스테르의 합성 및 열안정성)

  • Baek, Jin-Wook;Chung, Keun-Wo;Kim, Young-Wun;Seo, In-Ok;Han, Jung-Sik
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.05a
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    • pp.130-134
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    • 2002
  • Polyol esters were synthesized by condensation reaction of polyols (PE and DIPE) and linear acids such as valeric acid, caproic acid, heptylic acid and caprylic acid. The structures of polyol esters were confirmed by gas chromatography. Hot tube test was used to measure thermal stability of polyol esters and its thermal properties depended on the structure of acid moiety contained in polyol esters.

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Polyhydroxyamic Acid from 3,3′ - Dihydroxybenzidine and Pyromellitic Dianhydride as a Fire-safe Polymer

  • Park, Seung Koo;Farris, Richard J.;Kantor, Simon W.
    • Fibers and Polymers
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    • v.5 no.2
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    • pp.83-88
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    • 2004
  • In order to assess the potential of the hydroxy-containing polyamic acid (PHAA) synthesized from 3,3'-dihydroxy benzidine and pyromellitic dianhydride for a fire-safe polymer, the cyclization pathway of PHAA has been investigated using a model compound prepared from 2-aminophenol and phthalic anhydride. The reaction was monitored. by $^1{H-nuclear}$ magnetic resonance. N-(2-hydroxyphenyl) phthalamic acid is converted to N-(2-hydroxyphenyl) phthalimide at ca. 175$^{\circ}C$, showing endothermic reaction. The imide structure is rearranged to the benzoxazole structure over ca. $400^{\circ}C$. These results are similar with that of PHAA. According to pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) data, water and carbon dioxide are released during the cyclization and rearrangement reaction. One DMAc molecule is complexed with one carboxyl acid group in PHAA, which accelerates the imidization process to release more easily the flame retardant, water.

A Study on the Valve Regulated Lead-Acid Battery using Phosphoric Acid Gel Electrolyte (인산 겔 전해질을 사용한 밀폐형 납축전지에 관한 연구)

  • Ju, Chan-Hong;Park, Keun-Ho
    • Journal of the Korean Applied Science and Technology
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    • v.20 no.4
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    • pp.296-308
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    • 2003
  • The capacity and long life of gel electrolyte batteries is connected with gas recombination producting $PbO_2$ and Pb electrode. We were prepared with phosphoric acid gel electrolyte to know gel characteristics per density to assemble VRLA batteries. We studied by measuring electrolyte dispersion using Brewster-angle microscope(BAM), charge-discharge cycle and electrode structure using scanning election microscope(SEM) per electrolyte density. As a results, phosphoric acid density 1.210 was excellent gel dispersion in sol condition, electrode condition after fifty cycles in this study.

Synthesis and Thermal Stability of Polyol Esters (폴리올 에스테르의 합성 및 열 안정성)

  • Chung, Keun-Wo;Baek, Jin-Wook;Kim, Young-Wun;Seo, In-Ok;Han, Jeong-Sik
    • Tribology and Lubricants
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    • v.18 no.5
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    • pp.319-323
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    • 2002
  • Polyol esters were synthesized by condensation reaction of polyols (PE and DiPE) and linear acids such as valeric acid, caproic acid, heptylic acid and caprylic acid. The structures of polyol esters were confirmed by gas chromatography. Hot tube test was used test was used to measure thermal stability of polyol esters and its thermal properties depended on the structure of acid moiety contained in polyol esters.

Electrical Measurement of SOx Dew Point (SOx노점의 전기적 측정)

  • Chun, Y.N.;Yong, K.J.;Chae, J.O.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.4
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    • pp.600-610
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    • 1995
  • When combustion gas is cooled down below the dew point of sulfuric acid vapor in the heat recovery systems, condensation occurs. Since the condensed sulfuric acid solution causes low-temperature corrosion in materials, it is important to measure the SOx dew point by electric measurement. In this study, two kinds of probes having electric gaps of 1mm or 2mm were used. and experiments were carried out by the parameters of sulfuric acid vapor and water vapor concentration. The changes of electric current caused by sulfuric acid condensed on the surface of probe according to the cooling rate and the probe head surface temperature were sudied. The opimum cooling rate was decreased with the increasing of water vaper concentration regardless of sulfuric acid concentration. The sensitivity of electric current is improved for the narrower gap(1mm) of ring electrodes, but it rarely affects the SOx dew point measuring of different probes according to the change of cooling rate.

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