Review on the criteria anticipated for the fabrication of highly efficient ZnO-based visible-light-driven photocatalysts

Abstract Electrochemical surface oxidation of carbon black Vulcan XC-72 and multiwalled carbon nanotube (MWNT) has been compared following potentiostatic treatments up to 168 h under condition simulating PEMFC cathode environment (60 °C, N2 purged 0.5 M H2SO4, and a constant potential of 0.9 V). The subsequent electrochemical characterization at different treatment time intervals suggests that MWNT is electrochemically more stable than Vulcan XC-72 with less surface oxide formation and 30% lower corrosion current under the investigated condition. As a result of high corrosion resistance, MWNT shows lower loss of Pt surface area and oxygen reduction reaction activity when used as fuel cell catalyst support.

http://ma.ecsdl.org/content/MA2005-02/33/1168.full.pdf

Durability Investigation of Carbon Nanotube as Catalyst Support for Proton Exchange Membrane Fuel Cell Electrode

Abstract Four optimising methods for variable selection in multivariate calibration have been described: one for determining the optimal subset of variables to give the best possible root-mean-square error of prediction (RMSEP) in a multiple linear regression (MLR) model, the second for determining the optimal subset of variables which produce a model with RMSEP less than or equal to a given value. Algorithms three and four were identical to algorithms one and two, respectively, except that this time they use a cost function derived from a partial least squares (PLS) model rather than an MLR model. Applied to a typical set of pyrolysis mass spectrometry data the first variable selection method is shown to reduce the RMSEP of the optimal MLR or PLS model significantly when the number of variables is decreased by approximately half. Alternatively, the number of variables may be reduced substantially (> 10-fold) with no loss in RMSEP.

Genetic algorithms as a method for variable selection in multiple linear regression and partial leas

Pseudorotaxanes formed between secondary dialkylammonium salts and crown ethers

Greening extraction techniques to improve the sensitivity and the selectivity of analytical methods is the sustainable alternative to classical sample-preparation procedures used in the past In this update, we review the main strategies employed in the scientific literature to reduce deleterious side-effects of extraction techniques We demonstrate that the evolution of sample-treatment procedures is focused on the simultaneous improvement of the main analytical features of the method and its practical aspects, including the economic case

The role of green extraction techniques in Green Analytical Chemistry

Due to excellent properties, recently ZnO nanomaterials are used as very efficient photocatalysts for the photocatalytic degradation of toxic organic dyes and chemicals under various light radiations. In this article we used a new and simple method for synthesis of high efficient AgxZn1−xO (x = 0, 0.3, 0.5, 1, 2, 4, 6) nano photocatalyst in visible region. The process is simple, cost-effective and can be easily scaled-up. It was shown that the catalytic behavior of ZnO that is synthesized with this method has good efficiency about 63% for degradation of methylene blue in visible-light illumination.With doping of a little (0.5%) Ag the photocatalytic activity in the visible-light range is notably improved with a maximum effeciency of 98% degradation of methylene blue. In this work Ag doped and oxygen vacancy defects on the surface of ZnO nanoparticles benefit the separation of photogenerated electron–hole pairs, thus lead to enhancing the photocatalytic activity. The properties of the nanoparticles were characterized by the employments of UV–Vis spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy(FT-IR),photoluminescence (PL), field emission scanning electron microscopy (FESEM) and scanning energy dispersive X-ray spectroscopy (EDS).

New and highly efficient Ag doped ZnO visible nano photocatalyst for removing of methylene blue

A review to recent developments in modification of carbon fiber electrodes

Selective uranyl cation detection by polymeric ion selective electrode based on benzo-15-crown-5

A new cerium (III) ion selective electrode based on 2,9-dihydroxy-1,10-diphenoxy-4,7-dithia decane, a novel synthetic ligand

Recently, much attention has been paid to chromatographic characteristics and applications of crown ethers. These compounds were employed as chiral stationary phase for resolution of various racemic compounds in high performance chromatography and capillary electrochromatography techniques. Crown ethers also used in gas chromatography as the stationary phase. Recently, it has been found that, crown ethers also may be useful in cation chromatographic separation in ion chromatography for the determination of alkali and alkaline-earth cations, ammonium, and amines. In this paper we have an overview on these applications of crown ethers.

Roya Mohammadzadeh Kakhki

Papers

New and highly efficient Ag doped ZnO visible nano photocatalyst for removing of methylene blue

A review to recent developments in modification of carbon fiber electrodes

Selective uranyl cation detection by polymeric ion selective electrode based on benzo-15-crown-5

A new cerium (III) ion selective electrode based on 2,9-dihydroxy-1,10-diphenoxy-4,7-dithia decane, a novel synthetic ligand

Application of crown ethers as stationary phase in the chromatographic methods