The viscoelasticity of a fluid was tuned with the Faradaic reaction (11-ferrocenylundecyl)trimethylammonium bromide (FTMA), "redox-switchable" surfactant. An aqueous solution reduced form FTMA exhibited remarkable in presence sodium salicylate (NaSal) because formation three-dimensional entanglement wormlike micelles. Electrolytic oxidation caused viscosity system to dramatically decrease and elasticity disappear. This drastic arose from disruption novel electrorheological phenomenon is...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSpontaneous Vesicle Formation from Aqueous Solutions of Didodecyldimethylammonium Bromide and Sodium Dodecyl sulfate MixturesYukishige Kondo, Hirotaka Uchiyama, Norio Yoshino, Katsuhiro Nishiyama, Masahiko AbeCite this: Langmuir 1995, 11, 7, 2380–2384Publication Date (Print):July 1, 1995Publication History Published online1 May 2002Published inissue 1 July...

This Article reports on the influence of light irradiation stability emulsions prepared using a photoresponsive gemini surfactant (C7-azo-C7) having an azobenzene skeleton as spacer. When mixtures trans C7-azo-C7 aqueous solution and n-octane are homogenized, stable obtained in specific region weight fraction concentration. Fluorescence microscopy observations small amount fluorescent probes show that oil-in-water (O/W)-type. UV O/W promotes cis isomerization leads to coalescence oil...

The influence of ultraviolet (UV) light irradiation on the emulsification properties mixtures an anionic surfactant, sodium dodecyl sulfate (SDS), and a photoresponsive cationic 2-(4-(4-butylphenyl)diazenylphenoxy)ethyltrimethylammonium bromide (C4AzoTAB), containing azobenzene group has been investigated. When n-octane aqueous SDS/trans-C4AzoTAB solution are homogenized, stable emulsions obtained in regions specific surfactant concentrations molar ratios mixed surfactants. for over week...

An amphiphilic anionic azobenzene derivative, soluble in water, formed a monolayer on an aqueous subphase containing water-soluble polycation. The monolayers were transferred onto solid substrate by the Langmuir−Blodgett (LB) technique. XPS measurements showed that ion exchange reaction proceeded almost completely at air−water interface and ratio of monomer unit polycation to was unity. UV/vis absorption IR indicated photoisomerized reversibly LB films alternate illumination with UV vis...

Formation of water (W) in supercritical carbon dioxide (scCO2) (W/scCO2) type microemulsions was examined using four hybrid surfactants, the sodium 1-oxo-1-[4-(tridecafluorohexyl)phenyl]-2-alkanesulfonates (FC6-HCn, n = 2, 4, 6, and 8), which have a hydrocarbon chain different length fluorocarbon one molecule an Aerosol-OT (AOT) analogue fluorinated twin tail surfactant, bis(1H,1H,2H,2H-heptadecafluorodecyl)-2-sulfosuccinate (8FS(EO)2). For comparison AOT also used. The surfactants (FC6-HCn)...

A ferrocene-containing, redox-active cationic lipid that can be transformed using electrochemical methods yields large differences in cell transfection depending on the oxidation state of lipid. Expression enhanced green fluorescent protein and firefly luciferase occurs at very high levels when DNA lipoplexes are formulated reduced state. In contrast, is negligible oxidized used. These observations suggest basis a general method could used to transform inactive lipoplex formulations an...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSyntheses of Hybrid Anionic Surfactants Containing Fluorocarbon and Hydrocarbon ChainsNorio Yoshino, Katsumi Hamano, Yota Omiya, Yukishige Kondo, Atsushi Ito, Masahiko AbeCite this: Langmuir 1995, 11, 2, 466–469Publication Date (Print):February 1, 1995Publication History Published online1 May 2002Published inissue 1 February 1995https://doi.org/10.1021/la00002a016RIGHTS & PERMISSIONSArticle Views438Altmetric-Citations61LEARN ABOUT THESE...

We already reported spontaneous vesicle formation in aqueous solutions of bis(11-ferrocenyl(undecyl))dimethylammonium bromide (11-BFDMA), a newly synthesized ferrocene-modified double-chain-type cationic surfactant (Kakizawa, Y.; Sakai, H.; Nishiyama, K.; Abe, M. Langmuir 1996, 12, 921.). have examined this study electrochemical control 11-BFDMA using the redox reaction ferrocenyl groups their molecules. Static light scattering, conductivity, and cyclic voltammogram measurements on solution...

We have examined the interfacial properties of several fluorinated surfactants in a water/CO2 mixture with pendant drop tensiometer and revealed relationships between properties, surfactant structure, microemulsifying power. employed following Aerosol-OT analogue that two tails: bis(1H,1H,5H-octafluoropentyl)-2-sulfosuccinate (di-HCF4), sodium bis(1H,1H,9H-hexadecafluorononyl)-2-sulfosuccinate (di-HCF8), bis(1H,1H,2H,2H-heptadecafluorodecyl)-2-sulfosuccinate (8FS(EO)2),...

The effects of the structural factors surfactants such as CO2-philic tail length and molecular structure on formation water-in-supercritical CO2 (W/scCO2) type microemulsions were examined at various temperatures pressures for fluorinated Aerosol-OT (AOT) analogue surfactants, sodium bis(1H,1H,5H-octafluoropentyl)-2-sulfosuccinate (di-HCF4), bis(1H,1H,7H-dodecafluoroheptyl)-2-sulfosuccinate (di-HCF6), bis(1H,1H,9H-hexadecafluorononyl)-2-sulfosuccinate (di-HCF8),...

Solution properties of novel double-tailed cationic surfactants with two ferrocenyl groups introduced to the end each alkyl chain ({Fc(CH2)n}2N+(CH3)2Br- (n-BFDMA; n = 5, 11)) have been investigated by light scattering, relative conductivity, and polarized optical microscope measurements. The aggregation form n-BFDMA is fairly dependent on its concentration. Scattered intensity from a diluted (<10-3 mol/L) 5-BFDMA solution shows continuous increase at concentrations above 3 × 10-5 mol/L...

A new azobenzene derivative, bis[4-(3-methylbutoxy)phenyl]diazene (DC-azo), was synthesized as yellow powder through a three-step reaction. DC-azo crystallized from mixture of acetone/water in the form highly insulating gold-colored crystals with specular reflectance 21% over wavelength range 520-800 nm. The CIELAB color space indicated that were slightly more reddish and less yellowish than metallic Au. retained their gold coloration under dry conditions stable up to 383 K. X-ray...

The structure of the mixed Langmuir and Langmuir−Blodgett (LB) films arachidic acid (AA) perfluorotetradecanoic (PA) are investigated. Surface pressure−area isotherms AA PA fall between those pure PA, indicating that additivity rule holds in this system. This shows two components phase-separated or ideally mixed. results transmission reflection−absorption IR spectroscopic measurements LB reveal composition is same with spreading solution orientation does not change mixing. Molecular axes...

The exchange of a fluorocarbon-hydrocarbon hybrid surfactant between monomer and micelle states in deuterium oxide has been investigated through 19F NMR 1H experiments. CF3 group the gives two kinds signals corresponding to states, indicating slow on time scale. lifetime (taumic) micelle, estimated by line shape analysis signals, is 2.0 ms at cmc, 102 103 times longer than that general micelles. Pulsed-gradient spin-echo (PGSE) experiments show forms considerably small micelles with...

Ultrathin films of small organic molecules are patterned with nanostructures, the size which is controlled by adjusting intermolecular interactions. Nanowires controllable widths form in mixed Langmuir–Blodgett (LB) long-chain fatty acid and hybrid carboxylic (see figure). Templates, can confine both inorganic materials, fabricated from three-component LB films, containing an amphiphilic silane-coupling agent.

We report characterization of the nanostructures complexes formed between redox-active lipid bis(n-ferrocenylundecyl)dimethylammonium bromide (BFDMA) and DNA using small-angle neutron scattering (SANS) cryogenic transmission electron microscopy (cryo-TEM). A particular focus was directed to influence oxidation state (where reduced BFDMA has a net charge +1 oxidized +3) on solution aggregates formed. Complexes were characterized over range ratios (1.1:1, 2.75:1, 4:1) in solutions 1 mM Li2SO4....

This article reports the influence of redox reactions on emulsions n-octane and an aqueous solution a ferrocene-containing surfactant (FTMA; (11-ferrocenylundecyl)trimethylammonium bromide). Above certain concentration, stable O/W were formed from reduced FTMA; in contrast, mixtures oxidized FTMA did not form at any concentration. Furthermore, adding oxidant to led coalescence oil (octane) droplets emulsions, subsequently, water (aqueous solution) phases fully separated i.e., demulsification...

Abstract High aspect ratio SiO 2 /SiN (ON) stacked layer etching using hydrofluorocarbon gases was conducted with various ratios of H, F, and C to achieve higher rates precise profile control. The experimental were 3 HF 5 , 4 H F 6 10 . oxygen gas flow rate mixing optimized maximize mask selectivity while avoiding clogging at the top mask. For comparison, /CH /Ar/O /C 8 used as reference mixtures. initial screening narrowed candidate pool gases: At equivalent power, condition achieved a 15%...