The tensile strength of cement paste was increased by 56% and the modulus and ductility were increased by 39% by using silane-treated carbon fibers and silane-treated silica fume, relative to the values for cement paste with as-received carbon fibers and as-received silica fume. Silane treatment of fibers and silica fume contributed about equally to the strengthening. Silane treatment of fibers...

Detection of phosphate using amperometry was investigated. The phosphomolybdate complex, formed by addition of nitric acid, ammonium molybdate and phosphate, was reduced at a carbon paste electrode polarised at +0.3V (versus Ag/AgCl). The major characteristics observed were simplicity of the equipment, a limited consumption of reagents and a low detection limit (0.3mumoll(-1)), with a linear ra...

We have performed several studies to determine the electrochemical properties of Cu(II) binding by alfalfa biomass using carbon paste alfalfa-modified electrodes. Experimental conditions such as alfalfa-carbon paste concentrations, solution pH, and metal preconcentration times were determined. Results of the electro-chemical studies have shown that an increase in response was observed by increa...

A sensitive and convenient electrochemical method was developed for the simultaneous determination of the isomers of Ponceau 4R and Amaranth by an expanded graphite paste electrode (EGPE). The EGPE was prepared by mixing EG with solid paraffin. Compared with flake graphite paste and carbon paste electrodes, the EGPE showed higher electrocatalytic activity towards the oxidization of Ponceau 4R a...

The current-degradation mechanism of a fully sealed, carbon-nanotube field emission display is investigated experimentally and theoretically. From residual gas analysis, it is strongly evidenced that CH3 radicals from the organic materials in the paste deteriorate emission properties. Based on ab initio methods, it is found that CH3 radicals can increase electrical resistance of the nanotube an...

A chemically modified carbon paste electrode with multiwall carbon nanotube (MWCNT) was prepared and used as a sensor for Cu2+  ion. The unique chemical and physical properties of CNT have paved the way  to  new  and  improved  sensing  devices.  A  central  composite chemometrics  design  was  applied  for  multivariate  optimization  of the  effects  of  three  significant  parameters  (...

a carbon-paste electrode (cpe) chemically modified with the n-4,4'-azodianiline(ferrocenyl schiff base) complex and multi wall carbon nanotubes (adafcnte) was used as a highly sensitive electrochemical sensor for determination of trace amounts of atenolol. the oxidation peak potentials in cyclic voltammogram of adafcnte occurred around 550 mv vs ag/agcl (at ph 6.0) while this peak potentia...

A chemically modified carbon paste electrode with 2-chlorobenzoyl ferrocene (2CBF) and carbon nanotube (2CBFCNPE) was employed to study the electrocatalytic oxidation of ascorbic acid in aqueous solution using cyclic voltammetry, square wave voltammetry and chronoamperometry. The diffusion coefficient (D = 1.42 × 10-6 cm2 s-1), and the kinetic parameter such as ...