• 제목/요약/키워드: Ammonium Salts

검색결과 177건 처리시간 0.027초

Electrochemical Properties of Buckminsterfullerene ($C_{60}$) in Acetonitrile Containing Quarternary Ammonium Electrolytes

  • Kim, Il Kwang;Kim, Hyun Jin;Oh, Gi Su;Jeon, Il Chol;Ahn, Byoung Joon
    • 분석과학
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    • 제8권4호
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    • pp.675-682
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    • 1995

  • Thin films of buckminsterfullerene($C_{60}$) formed by solution drop casting on Pt foil electrode surfaces were studied by cyclic voltammetry(CV) in acetonitrile(MeCN) containing quaternary ammonium or alkali-metal salts as supporting electrolyte. The electrochemical behaviors of $C_{60}$ films are found to be strongly dependent on the nature of the supporting electrolytes, especially with tetrabutyl ammonium perchlorate (TBAP, $NBu_4ClO_4$), and tetrabutyl ammonium tetrafluoroborate ($TBABF_4$, $NBu_4BF_4$). Reasonably stable films are formed into which electrons can be injected. The interaction of $C_{60}$ film with the quaternary ammonium cation may produce the fulleride salts $(TBA^+)(C{_{60}}^-)$ and $(TBA^+)_2(C{_{60}}^{2-})$. The bulk electroreduction with a controlled potential to generate the soluble $C{_{60}}^{3-}$ anions(dark red-brown color) is followed by electrooxidative deposition to produce a neutral $C_{60}$ film on the surface. The peak currents($I_{pc}$ and $I_{pa}$) of these thin film were dramatically decreased with repetitive potential scanning. These results could be explained by the adsorption-desorption phenomena and ion pairing interaction of reduced species($C{_{60}}^-$, and $C{_{60}}^{2-}$) onto the electrode surface. The peak current changes and peak potential shifts of the thin $C_{60}$ film in cyclic voltammograms formed from solution were observed by varying scan rates.

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Myristyl 지방족기를 함유하는 제4급 암모늄염에 의한 PET 섬유의 감량가공 효과 (Weight Loss Effects of PET Fibers by Quaternary Ammonium Salts Containing Myristyl Aliphatic Group)

  • 박창환;근장현;김영근;박홍수
    • 한국응용과학기술학회지
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    • 제11권2호
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    • pp.139-146
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    • 1994

  • MDABM and MDAEW, as a accelerating weight loss agents, were prepared by adding water to myristyldimethylbenzylammonium bromide(MDAB) and myristyldimethylethylammonium ethyl sulfate (MDAE) synthesized. As a result of weight loss finishing of the MDABW and MDAEW with NaOH on PET fiber, the ratio of weight loss of MDABW was very larger than that of MDAEW. This result showed that quaternary ammonium bromide had higher weight loss effect than quaternary ammonium sulfate, and the ratio of weight loss was greatly varied with the kind of quaternary ammonium salts used. In these conditions, proper treatment concentration, treatment time, and treatment bath ratio were about 8g/l, $6O{\sim}90min$, and $40:1{\sim}50:1$, respectively.

  • https://doi.org/10.12925/jkocs.1994.11.2.15 인용 PDF

Ammonium Caprylate 와 Ammonium Caprate 溶液의 表面張力 (The Surface Tension of Solutions of Ammonium Caprylate and Ammonium Caprate)

  • 한만운;이종만
    • 대한화학회지
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    • 제7권4호
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    • pp.277-279
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    • 1963

  • The surface tension of solutions of synthesized ammonium caprylate and ammonium caprate was measured by the ring method. The changes with of surface tension of solution of ammonium caprylate showed evidently that the salt had the critical micelle concentration(c.m.c.) at $30^{\circ}C$. The c.m.c. values of above two salts were determined from the change of surface tension of solution with concentration at various temperatures. The temperature dependence of the c.m.c. and the influence of addition of excess ammonia on the c.m.c. were also investigated.

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실리카겔에 담지된 4급암모늄염 유도체의 합성 및 이온교환 특성 (Preparation of Quaternary Ammonium Salt Derivatives Supported on Silica gel and Its Ion Exchange Characteristics)

  • 안범수
    • 한국응용과학기술학회지
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    • 제25권1호
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    • pp.65-72
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    • 2008

  • The ion exchangers supported on silica gel containing primary, secondary, or tertiary amine groups show a behaviour that is weakly acidic, while the quaternary salts are strongly acidic. These properties change according to the hydrophilicities of the modifier functional groups. Ammonium salt derivatives supported on silica gel were prepared from silica modified with 3-Aminopropyltriethoxysiliane and N-3-(Trimethoxysilyl)propylehtylene diamine. The preparation and the ion exchange properties of two systems were discussed. Two systems have different hydrophilicities and contain ammonium chloride derivatives of 3-amminopropyltriethoxysilane and N-3-(triehtoxysilyl)propyl ethylene diamine supported on silica gel, $SA^+/Cl^-$ and $SA^+/Cl^-$, respectively. The high affinity to perchlorate ion presented by the $SA^+/Cl^-$ through the equilibrium studies of ion exchange led us to its application as an ion selective electrode for the perchlorate ion. The determination of the perchlorate ion in the presence of other anions and in complexes is very difficult. Few analytical methods are available and most of them are indirect. Both materials showed potential use as an ion exchanger; they are thermically stable, achieve equilibrium rapidly in the presence of suitable exchanger ions, and are easily recovered.

  • https://doi.org/10.12925/jkocs.2008.25.1.9 인용 PDF KSCI