• Title/Summary/Keyword: chlorides

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The Research on the Ladder System for Corrosion Monitoring (부식 모니터링을 위한 Ladder system에 관한 연구)

  • 송호진;문홍식;이상국;정영수
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.05a
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    • pp.671-676
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    • 2001
  • Reinforcement corrosion is major problem for those who own and maintain reinforced concrete structures exposed to chlorides. It is well understood that the form of corrosion is more problematic than corrosion found elsewhere, Because concrete has no apparent signs that there is anything amiss until the process of deterioration is relatively far advanced. The objective of this research is to develop the ladder system which monitors the corrosion of reinforcing steels in concrete. This system can be used to assess the corrosion condition and corrosion rate of steel in concrete, which can give timely repair and strengthening of steel in concrete structure.

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Radical Ring-Crossover Polymerization of Macrocycles with Radically Exchangeable Dynamic Covalent Bonds

  • Otsuka, Hideyuki;Yamaguchi, Go;Takahara, Atsushi
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.320-320
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    • 2006
  • The authors report the synthesis and radical ring-crossover polymerization of macrocycles with radically exchangeable dynamic covalent bonds. The macrocyclic compounds with alkoxyamine units were designed and synthesized by condensation from alkoxyamine-based diol and the corresponding acid chlorides in the presence of pyridine under high-dilution condition. The macrocycles can thermally polymerize by intermolecular radical crossover reaction. Furthermore, the poly(alkoxyamine)s depolymerized to the monomers principally by the intramolecular radical exchange process under high-dilution conditions.

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Syntheses and Central Nervous Depressant Activities of Piperine Derivatives (V) (피페린 유도체의 합성 및 중추 억제작용에 관한 연구(V) -Methylenedioxyphenylalkenoic Acid Amide 유도체-)

  • 도경삼;임중기;우경식;이은방
    • YAKHAK HOEJI
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    • v.30 no.4
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    • pp.163-168
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    • 1986
  • Thirteen compounds were synthesized by condensing the N-heterocyclic amines (piperidine, pyrrolidine, morpholine) and secondary aliphatic amines (dimethylamine, diethylamine) with 3,4-methylenedioxyphenylalkenoic acid chlorides for developing CNS depressants. Among them, N, N-diethyl-3,4-methylenedioxycinnamamide (IX) and N, N-dimethyl-5-(3,4-methylenedioxyphenyl)-2, 4-pentadienoic acid amicle (XII) exhibited strong activity in antagonism against pentylenetetrazole-induced convulsion, strychnine-induced convulsion and maximal electroshock seizure. N, N-Dimethyl-3, 4-methylenedioxycinnamide (VIII) showed more potent activity in antagonism against strychnine-induced convulsion and maximal electroshock seizure and in the prolongation of hexobarbital sleeping time.

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A Study on the Removal Effect of Sewage Treatment Effluent by Ultrafilter Membrane Species (한외여과막의 모듈형태에 따른 하수처리장 방류수의 처리 효과)

  • 김영규
    • Journal of Environmental Health Sciences
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    • v.24 no.1
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    • pp.19-23
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    • 1998
  • This study has designed to investigate the removal effect of sewage treatment effluent by ultrafilter membrane species and then to analyze the change of pH, bacteria and E. coli., the concentration of chlorides. Ultra filtration process did not effective to remove chloride, Ca and Mg. Spiral type ultrafiltration process was more effective to remove chemical oxygen demand of sewage treatment effluent than Hollow type ultrafiltration process. The flux of spiral wound ultrafilter was higher than the hollow fiber ultrafilter.

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Multiform Oxide Optical Materials via the Versatile Pechini-type Sol-Gel Process

  • Lin, J.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1247-1250
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    • 2008
  • This presentation highlights work from the authors' laboratories on the various kinds of oxide optical materials, mainly luminescence and pigment materials with different forms (powder, core-shell structures, thin film and patterning) prepared by the Pechini-type sol-gel (PSG) process. The PSG process which uses the common metal salts (nitrates, acetates, chlorides etc) as precursors and citric acid (CA) as chelating ligands of metal ions and polyhydroxy alcohol (such as ethylene glycol or poly ethylene glycol) as cross-linking agent to form a polymeric resin on molecular level, allowing the preparation of many forms of luminescent materials.

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Synthesis of 2-Substituted Benzimidazoles as Antiinflammatory Agents (2-치환-벤즈이미다졸류의 합성 및 소염작용)

  • Moon, Seung-Wook;Jahng, Yurng-Dong;Seoh, Byeong-Chon
    • YAKHAK HOEJI
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    • v.36 no.1
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    • pp.7-11
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    • 1992
  • 2-Substituted benzimdazoles were prepared by reacting o-phenylenediamine with acid chlorides, which has advantages over the known synthetic procedures. The compounds prepared showed no significant antiinflammatory activity, thus are of no interest as antiinflammatory agents.

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Synthesis of N-Substituted 5-Hydroxyanthranilic Acid (N-치환 5-Hydroxyanthranilic acid의 합성)

  • 문정술;이강노;임중기;우원식;박상우
    • YAKHAK HOEJI
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    • v.37 no.3
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    • pp.243-246
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    • 1993
  • Six N-substituted-5-hydroxyanthranilic acids were synthesized by the coupling reaction of 5-tosyloxyanthranilic acid ethyl ester with corresponding acid chlorides. The structure of the obtained compounds was proved by NMR and IR. These compounds did not inhibit the growth of micro-organisms while suppressed HSV-1 replication in vero cell at 100 $\mu\textrm{g}$/ml.

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Preparation of Spherical (Zr, Sn)TiO4 Powders by Ultrasonic Spray Pyrolysis (초음파 분무 열분해법에 의한 $(Zr, SN)TiO_4$ 구형 미분말의 합성)

  • 조서용;이종흔;김명철;박순자
    • Journal of the Korean Ceramic Society
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    • v.31 no.5
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    • pp.465-470
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    • 1994
  • Fine, spherical (Zr, SN)TiO4 powders were prepared from the aqueous solution of metal chlorides by ultrasonic spray pyrolysis. Single phase (Zr, SN)TiO4 powders could be obtained above $700^{\circ}C$ (=temperature of the reactor) and all powders exhibited sizes in the range of 0.1 to 2.0 ${\mu}{\textrm}{m}$ and a narrow size distribution. The sintering properties of the prepared powders were better than those of the powders from solid-state reaction.

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Synthesis and Surface Activities of Perfluoro Hetero Type compounds (헤테로형 불소계 소화약제의 물리적 특성에 관한 연구)

  • 이승열;박노춘
    • Journal of the Korean Society of Safety
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    • v.13 no.1
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    • pp.64-69
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    • 1998
  • Three kinds of N-fluoroacyl carboxy pyridinium chlorides were synthesized by the reaction of pyridine-carboxylic acid such as pyridine-2-carboxylic, pyridine-3-carboxylic and pyridine-4-carboxylic acid with long chain perfluoroacyl chloride. The surface chemical properties including surface tension, foaming power, foam stability, effectiveness of wettability and solubilizing effect were measured. These compounds showed good surface activities as emulsifying agent, solubilizing agent and fire-fighting agent.

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Polystyrene Supported Al(OTf)3: an Environmentally Friendly Heterogeneous Catalyst for Friedel-Crafts Acylation of Aromatic Compounds

  • Boroujeni, Kaveh Parvanak
    • Bulletin of the Korean Chemical Society
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    • v.31 no.11
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    • pp.3156-3158
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    • 2010
  • Stable and non-hygroscopic polystyrene supported aluminium triflate (Ps-$Al(OTf)_3$), which is prepared easily from cheap and commercially available compounds was found to be an environmentally friendly heterogeneous catalyst for Friedel-Crafts acylation of arenes using acid chlorides in the absence of solvent under mild reaction conditions. The catalyst can be reused up to five times after simple washing with dichloromethane.