• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.6
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• pp.496-500
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• 2003

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electrodes as well as micellar assemblies, which can be profitably utilized for display devices, photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator. Fromherz et al studied the self-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface[1]. The electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency(ΔF) and resonant resistance(R). The redox process of viologen was observed with resonant frequency(ΔF).

• Macromolecular Research
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• v.13 no.6
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• pp.499-505
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• 2005

Ordered mesoporous materials with a hydrothermally-stable, protozeolitic framework were prepared by exploring the direct conversion of inorganic species based on co-surfactant templating systems. To confer hydrothermal stability on the mesoporous aterials, the organic-inorganic hybrids were heat-treated in strongly basic media. Co-surfactant templating systems of cetyltrimethylammonium bromide [$C_{16}H_{13}(CH_{3})_{3}$NBr, CTAB] with 1,3,5-trim­ethylbenzene (TMB) or a nonionic block copolymer of poly(ethylene oxide )-b-poly(propylene oxide )-b-poly(ethyl­ene oxide) ($EO_{20}PO_{70}EO_{20}$) were employed to improve the hydrothermal stability of the organic-inorganic self-assembly during the solid rearrangement process of the inorganic species. The mesoscopic ordering of the pore structure and geometry was identified by X-ray diffraction, small angle neutron scattering and electron microscopy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.403-406
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• 2002

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electroeds as well as micellar assemblies. which can be profitably utilized for display devices. photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator[1-3]. Fromherz et al studied the se1f-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface[4]. In this study, the electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency$({\Delta}F)$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.23-27
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• 2003

Molecular self-assembled of surfactant viologen are of recent interest because they can from functional electrodes as well as micellar assemblies, which can be profitably utilized for display devices, photoelectrochemical studies and electrocatalysis as electron acceptor or electron mediator. Fromherz et al studied the self-assembly of thiol and disulfide derivatives of viologens bearing long n-alkyl chains on Au electrode surface. The electrochemical behavior of self-assembled viologen monolayer has been investigated with QCM, which has been known as nano-gram order mass detector. The self-assembly process of viologen was monitored using resonant frequency$({\Delta}F)$ and resonant resistance(R). The redox process of viologen was observed with resonant frequency $({\Delta}F)$.

• Bulletin of the Korean Chemical Society
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• v.27 no.10
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• pp.1562-1566
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• 2006

Mesoporous silica films with three different pore sizes were prepared by using cationic surfactant, non-ionic surfactant, or triblock copolymer as structure directing agents with tetramethylorthosilicate as silica source in order to control the pore size and wall thickness. They were synthesized by an evaporation-induced self-assembly process and spin-coated on Si wafer. Mesoporous silica films with three different pore sizes of 2.9, 4.6, and 6.6 nm and wall thickness ranging from $\sim$1 to $\sim$3 nm were prepared by using three different surfactants. These materials were optically transparent mesoporous silica films and crack free when thickness was less than 1 m m. The photoluminescence spectra found in the visible range were peaked at higher energy for smaller pore and thinner wall sized materials, consistent with the quantum confinement effect within the nano-sized walls of the silica pores.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1142-1146
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• 1996

Cholesterol-containing surfactant was synthesized, and it was sonicated with monomer in water to form a vesicle solution. This vesicle solution was dried to construct a membrane which had a molecular multilayer structure. Using UV irradiation the monomer in this membrane were polymerized, and then surfactant was extracted by organic solvent. Using a X-ray diffractometer, the thickness of one layer and the regularity of the multilayer were measured. And scanning electron microscopy was conducted for fractured polymer film.

• Journal of Integrative Natural Science
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• v.1 no.2
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• pp.76-78
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• 2008

A series of the long-chain iron(II) alkylsulfonate hydrates were synthesized via self-assembly of surfactant alkyl chains in aqueous medium. Reaction of iron(II) salts with n-alkylsulfonate yields lamellar $Fe(CnH2n+1SO3)2{\cdot}4H_2O$. These compounds show a layered structure, as determined by XRD, consisting of alternating organic alkylsulfonate layers and inorganic iron(II) hydrate layers, with interlayer distances of upto 3.2 nm. This lamellar structure may be attributed to the amphiphilic nature of the surfactants, mediating the coordination and H-bionding interactions, and the hydrophobic alkyl chains. An alkyl chain packing of present system are differ from those of similar Cu(II) series, which are attributed from the size of hydrated metal(II) ions.

• Food Engineering Progress
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• v.21 no.3
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• pp.215-224
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• 2017

Resveratrol was incorporated into various combinations of single- and double-layer nanoemulsions, prepared by self-assembly emulsification and complex coacervation with chitosan, alginate, and ${\beta}$-cyclodextrin, respectively. Resveratrol nanoemulsions were composed of medium-chain trigacylglycerols (MCTs), $Tween^{(R)}$ 80, water, chitosan, alginate, and ${\beta}$-cyclodextrin. The corresponding mixtures were formulated for the purpose of being used as a nutraceutical delivery system. Resveratrol nanoemulsions were obtained with particle sizes of 10-800 nm, with the size variation dependent on the emulsification parameters including the ratio of aqueous phase and surfactant ratio. Resveratrol nanoemulsions were characterized by evaluating particle size, zeta-potential value, stability, and release rate. There were no significant changes in particle size and zeta-potential value of resveratrol nanoemulsions during storage for 28 days at $25^{\circ}C$. The stability of resveratrol in the double-layer nanoemulsions complexed with chitosan or ${\beta}$-cyclodextrin was higher, compared with the single-layer nanoemulsions.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1161-1172
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• 2009

Food nanoemulsion systems consisting of water and oleoresin capsicum (OC), polyoxythylene sorbitan esters (Tween 20, 40, 60, and 80), propylene glycol (PG), sucrose monostearate (SM), and their corresponding mixtures were formulated to use as food vehicles. Tween 80 produced OC nanoemulsions with stable dispersions as one-phase systems, and the dertermined emulsification efficiencies clearly distinguished the ability of the various surfactants to emulsify OC. The nanoemulsions were prepared by both ultrasonication and self-assembly, and the nanoemulsion areas were determined using phase diagrams by measuring the sizes of the emulsions. One-phase nanoemulsions were presented, with a multiple cloudy region and phase separation that were dependent on the particle size of the emulsion. The OC nanoemulsions prepared by ultrasonication using systems of OC/Tween 80/water, OC/Tween 80/water+PG, and OC/Tween 80/water+SM, resulted in particle sizes ranging from 15 to 100 nm. Finally, the nanoemulsions maintained their initial sizes during storage, ranging from 65 to 92 nm.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.3
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• pp.115-118
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• 2005

Currently, molecular devices are reported utilizing active self-assembled monolayers (SAMs) containing the nitro group as the active component, which has active redox centers [1]. SAMs are ordered molecular structures formed by the adsorption of an active surfactant on a solid surface. The molecules will be spontaneously oriented toward the substrate surface and form an energetically favorable ordered layer. During this process, the surface-active head group of the molecule chemically reacts with and chemisorbs onto the substrate In this paper, the electrical properties of the 4'4- di(ethynylphenyl)-2'-nitro-1-benzenethiolate was confirmed. This material is well known as a conducting molecule having possible application to molecular level negative differential resistance (NDR) device. To deposit the self-assembly monolayers onto the gold electrode, the prefabricated Au(1 l l) substrates were immersed into 0.5[mM/l] self-assembly molecule in THF solution. Then, the electrical properties and surface morphologies of 4' 4-di(ethynylphenyl)-2' -nitro-1-benzenethiolate were measured by using the ultra-high vacuum scanning tunneling microscopy (UHV-STM).