• Journal of the Korean Applied Science and Technology
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• v.7 no.2
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• pp.41-45
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• 1990

A Stability to the dispersion solvent, which is acetonitrile, dichloromethane, benzene, chloroform and acetonitrile-benzene(1:1,v/v) of {N-docosyl pyridinium)-TCNQ(1:2)complex was investigated by U.V Spectrophotometer and was confirmed stabilized on acetonitrile, the dichloromethane and acetonitrile-benzene (1:1,v/v) for seven hours. Using $CdCl_2$buffer solution as subphase for LB films deposition, it was achived successively to fabricate the Y-type LB films of (N-docosyl pyridinium)-TCNQ(1:2)complex. For the sake of verifying the deposition of LB films, U.V is measured by variation of nominal layer number.

• Journal of the Korean Chemical Society
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• v.25 no.4
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• pp.263-269
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• 1981

The substituted pyridinium salts of oxochloromolybdates(V) have been prepared characterized by visible and infrared spectra, and magnetic moments. The electrical conductance of aqueous solutions of substituted pyridinium salts have been measured over a range of concentrations. The results indicate that the complex anions are monomeric in the solid. The magnetic moments of the complexes are similar to the spin-only values. Substituted pyridines are present as pyridinium cation in solid state.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.2
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• pp.145-148
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• 2008

Cationic surfactant can be used as cosmetics and chemical dispersants. The variation of critical micelle concentration (CMC) with temperature over the range $40^{\circ}C$ to $60^{\circ}C$ for N-octadecyl pyridinium bromide was measured by drop methods. Thermodynamic quantities such as free energy, enthalpy, entropy and heat capacity for micellization of N-octadecyl pyridinium bromide in water were calculated by fourth-degree polynominal equation In the result, free energy change was decreased generally by the increment of temperature.

• Bulletin of the Korean Chemical Society
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• v.20 no.4
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• pp.400-402
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• 1999

• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1301-1303
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• 1998

• Membrane Journal
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• v.13 no.1
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• pp.54-63
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• 2003

The Preparation and electrochemical characterization of anion-exchange membranes containing pyridinium groups were performed. As a result, the pyridinium membranes showed good electrochemical properties, comparable to those of the commercial membranes, with electrical resistance of less than $3.0 {\Xi}cm^2$ in a 0.5 mol $dm^{-3}$ NaCl and high ionic permselectivity (the transport number of $Cl^-$ ions being 0.97). Moreover, water splitting in the membranes containing pyridinium group was about two or three order of magnitude lower than those in the commercial membranes (ｅ.ｇ. AM-1, Tokuyama Crop., Japan) at the same current density because the resonance effedt in the quaternary aromatic pyridinium group contributed to their molecular stability. In addition, the electrodialytic properties of the pyridinium membranes were evaluated in a semi-pilot scale.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1990.10a
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• pp.108-109
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• 1990

For the purpose of fabricating of L-B Films, (N-alkyl pyridinium)-TCNQ(1:1) complex is synthesized. This complex is verified by U.V, I.R and elemental analyzer.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2583-2588
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• 2013

A new type of solid and gel-state ionics based on siloxane pyridinium iodides was synthesized and used as electrolytes in dye-sensitized solar cells. The resulting electrolytes were characterized by $^1H$ NMR spectroscopy, TGA and diffusion coefficient. The synthesized siloxane pyridinium iodide electrolytes have characteristics of different chain length of siloxane moieties. The ion conductivities were given 2.7-3.2 S/cm. Among the three SiDPIs based electrolytes, DSSC employing the SiDPI2 gives an open circuit voltage of 0.704 V, a short-circuit current of 15.85 $mA/cm^2$ and conversion efficiency of 6.8% under light intensity of 100 $mW/cm^2$. In addition, the performance of the DSSCs showed relatively reasonable compared with the propylpyridinium iodide (PPI) electrolyte.

• Journal of the Korean Chemical Society
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• v.20 no.3
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• pp.193-197
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• 1976

The ultrasonic absorption has been measured in aqueous solution of dodecyl pyridinium chloride (DPC) at $20^{\circ}C$ over the frequency range of 0.1${\sim}$90 Mc.The excess absorption was observed only in solutions in which the concentration was higher than the critical micellar concentration(cmc). The mechanism for this feature was attributed to the reaction $M_2\;{\rightleftharpoons}\;M_1\;＋\;1.2Cl^-$ Where $M_2$ and $M_1$ and M1 are two types of micelle. The rate constants of the forward and the reverse reactions were $6.6{\times}10^5 sec^{-1}\;and\;2.7{\times}10^11sec^{-1}mol^{-1.2}$respectively. Some kinetic charateristics including the free energy, enthalpy and entropy were calculated.

• Bulletin of the Korean Chemical Society
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• v.15 no.10
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• pp.857-860
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• 1994

We have calculated the ${\pi}$-electron density, atom self-polarizability, and free valence on each atom of N-(2-chlorobenzyl)-pyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-2-chloropyridinium salts using a simple Huckel method in order to discuss their intramolecular photocyclization reaction in a qualitative method. Our calculation qualitatively predicts that photocyclization occurs through forming radicals as a reaction intermediate by breaking a C-Cl bond after photoexcitation into a triplet state via intersystem crossing from an initially excited singlet state. We noticed that this C-Cl bond breaking is aided by ${\pi}$-complex formation between a chlorine atom and the ${\pi}$ -electrons of the neighboring ring in the triplet state and a stronger ${\pi}$-complex bond makes C-Cl bond breaking, i.e., radical formation, much easier. A chlorine atom will form a stronger ${\pi}$ -complex bond to a benzyl ring of N-(benzyl)-2-chloropyridinium than a pyridinium ring of N-(2-chlorobenzyl)-pyridinium because the former can donate its ${\pi}$-electron more easily than the latter. The chlorine at position 15 of N-(2-chlorobenzyl)-2-chloropyridinium salt in the excited state also provides its ${\pi}$-electron to the benzyl ring. So this ${\pi}$-electron can increase the bond strength of the $\pi-complex.$ Therefore, the strength of ${\pi}$-complex follows the order of N-(2-chlorobenzyl)-2-chloropyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-pyridinium salts and thus the radical formation rate. This provides us with an intramolecular photocyclization reaction rate of the same order as given above.