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The electrochemical responses of chlorophenols can be effectively enhanced by using the surfactant cetyltrimethylammonium bromide (CTAB) in combination with a carbon paste electrode (CPE). The influence of CTAB on the electrochemical behavior of hydroquinone, phenol, 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, p-chloro-m-cresol and pentachlorophenol at the CPE was investigated in the phosphate buffer solution (pH 7). The concentration of CTAB affecting the electrochemical reaction of phenols was examined and the optimal concentration was 0.2 mM. In this research we have applied electrochemical methods, such as cyclic voltammetry and differential pulse voltammetry (DPV). The CPE modified with CTAB in DPV increased signal intensity for chlorophenols by around 5 to 13 times and was successfully applied to determination of chlorophenols in soil samples., Author(s): Arsim Maloku [sup.1], Liridon Berisha [sup.1], Granit Jashari [sup.2], Tahir Arbneshi [sup.1], Kurt Kalcher [sup.3] Author Affiliations: (1) grid.449627.a, 0000 0000 9804 9646, Departament of Chemistry, Faculty of Mathematical [...]

The theory of electromagnetic wave scattering by several finite length carbon nanotube (CNT) configurations, including singlewall CNT' s having a surfactant coating, CNT bundles and multiwall CNTs is described. Strong local field enhancement due to edge effects is inherent to metallic singlewall CNTs in the near-field zone, which has provided an additional mechanism of energy dissipation in a conductive host.

The pyrene-containing water-soluble nanoparticle is under electrostatic stress when diluted below the CMC of the surfactant and extremely rapid release of the hydrophobic content is observed when the cross-linker is cleaved. The method has combined the ease of physical entrapment and the precision of chemical ligation and is useful in the delivery and controlled release of pharmaceutical agents.

Time-resolved second-harmonic generation spectroscopy is used for examining the dynamics of hydrated electrons at the water/air interface. The location of the electron relative to the dividing surface is examined by using surfactants, which has shown that the electron is hydrated in the interfacial region, below the dividing surface.

The synthesis of monodisperse Ni nanoparticles which exhibited high catalytic activity in hydrogen generation from the hydrolysis of the ammonia-borane (H3NBH3) complex is reported. The Ni nanoparticle catalysis supported on the Ketjen carbon support represent a promising route for the practical development of the [H.sub.3]NB[H.sub.3] complex as a feasible hydrogen storage medium for fuel cell applications.

Hole-transporting framework formed by surfactant-templated sol-gel polycondensation of an electroactive phenylenevinylene-based organosilane precursor is described. Electroactive organosilicas with mesopores and large surface areas have great potential applications for novel photovoltaic and photocatalytic systems.

The thermal conductivity measurements of a carbon aerogel nanocomposite containing double-walled carbon nanotubes which were prepared by the sol-gel polymerization of resorcinol with formaldehyde in aqueous suspension containing a surfactant-stabilized dispersion of double-walled carbon nanotubes are presented. Enhanced thermal conductivities observed for carbon aerogel nanocomposites relative to pristine carbon aerogels are discussed based on comparison results from theory and literature.

Stable, homogeneous ultrathin films of uniformly dimensioned dual-pore carbon capsules with mesoporous walls and macroscopic empty cores are prepared by using layer-by-layer methods based on electrostatic interaction between a polyelectrolyte and a surfactant coating of the carbon capsules. The resulting dual-porous carbon capsule films are examined as a sensor substrate for vapors of different organic solvents.

The worm-to-sphere transition observed in cylindrical polymer brushes (CPBs) due to an ionic complex formed with the cationic CPB by anionic surfactant sodium dodecyl sulfate (SDS) is discussed. The drastic conformation switching observed between worms and spheres in the system could be applied to design intelligent nanoscale sensors and devices.

The complexes formed by a small protein, ubiquitin (UBI), and a negatively charged surfactant, sodium dodecyl sulfate (SDS), are characterized by using capillary electrophoresis (CE), circular dichroism (CD) and amide hydrogen-deuterium exchange (HDX). The study has helped in understanding the formation of the protein-SDS complexes formed during SDS polyacrylamide gel electrophoresis and has provided a new tool for studying proteins and detergents.

A modified polyol method, polyethylene glycol-600 (PEG-600) as reducing agent and oleic acid and oleyl amine as surfactants are used to synthesize self-assembled monodispersed 3 nm face centered cubic (fcc) FePd particles. The magnetic properties exhibited by ordered face centered tetragonal (fct) FePd phase could be useful for various technical applications.

Combination of atomic force microscopy (AFM) and confocal Raman microscopy (CRM) were used to study the surfactant distributions in model pressure-sensitive adhesive (PSA) films. The results showed that CRM acts as powerful compliments to AFM in characterizing the distribution of surfactant species in PSA film formation.

The effect of water droplet size and electrostatic interactions on the rotational diffusion of the probe molecules is studied. The reduction in the average reorientation time of fluorescein is shown to be a consequence of repulsive electrostatic interactions between the negatively charged probe and the anionic head groups of the surfactant di(2-ethylhexyl) sodium sulfosuccinate (AOT).

A study was conducted to examine the phase behavior and aggregation in mixed aqueous solutions of the anionic UV-absorber 2-phenylbenzimidazole-5-sulfonic acid sodium slat, PhBSA (Na salt), and the cationic surfactant cetyltrimethylammonium bromide, CTAB. The results showed that the aqueous mixtures of the stiff anionic compound PhBSA and the cationic surfactant CTAB have a rich and time-dependent phase behavior.

A detail study was performed to explore the exchange kinetics of cationic gemini surfactants of the alkanedily-[alpha]-[omega]-bis(tetradecyldimethylammonium bromide) type, with alkanediyl being 1,2-ethylene, 1,3-propylene, and 1,4-butylene. The exchange rate observed for 14-s-14 surfactants are found to be remarkably less compared to those of the conventional single-chain surfactants.

The persistence length of wormlike micelles composed of ionic surfactants which was calculated by means of self-consistent-field theory is presented.