Recent experimental evidence and computer modeling have shown that the crystallization of a range of minerals does not necessarily follow classical models and theories. In several systems, liquid precursors, stable pre-nucleation clusters and amorphous phases precede the nucleation and growth of stable mineral phases. However, little is known on the effect of background ionic species on the for...

Platinum(IV) can be determined spectrophotometrically with 5-chloro-2-hydroxythiobenzhydrazide on extraction into molten naphthalene from the aqueous phase with pH 2.2-6.0. Beer's law is obeyed in the concentration range 1.0-7.0 microg cm(-2) of Pt(IV) in 4-methyl-2-pentanone solution at 680 nm. The molar absorptivity and Sandell sensitivity are found to be 2.40 x 10(4) L mol(-1) cm(-1) and 8.0...

Plasma sputtering is one of the most promising methods for reducing the amount of platinum catalyst in porous electrodes for low temperature fuel cells. Here, a simulation of the platinum deposition by radio frequency plasma sputtering has been developed and compared with experimental results to allow optimization of the deposition process. In the simulation, the transport of sputtered atoms th...

Pt impregnated on a Sn-beta catalyst results in a very promising catalyst for the selective hydrogenation of α,β-unsaturated aldehydes, compared to the PtSn co-impregnated beta catalysts. Framework tin ions in the Sn-beta sample stabilize the nucleation of platinum nanoparticles inside the zeolite channel. These Pt(0)-Sn(4+) sites, which are only observed in the Pt/Sn-beta catalyst, have been s...

A sensitive spectrophotometric method for the determination of iodine species like iodide, iodine, iodate and periodate is described. The method involves the oxidation of iodide to ICl(2)(-) in the presence of iodate and chloride in acidic medium. The formed ICl(2)(-) bleaches the dye methyl red. The decrease in the intensity of the colour of the dye is measured at 520 nm. Beer's law is obeyed ...

Mixed halide perovskites with chlorine (Cl) content have received significant interest due to better charge transport properties and longer diffusion length compared pure iodine-based perovskites. The superior of Cl-doped improve solar cell device performance, although the quantification Cl composition in perovskite films remain difficult achieve. Hence, it is correlate Cl-quantity improved per...

We report size-dependent photodissociation and geminate recombination dynamics of the 1 1 chromophore in mass-selected I2-(CO2)" cluster ions, 0 I n I 22, by using nanosecond and picosecond pulsed laser sources in conjunction with a tandem time-of-flight mass spectrometer. Photoexcitation of these cluster ions results in the formation of two types of photofragment ions: 12--based photofragment ...

Reactive iodine compounds play a significant role in the atmospheric chemistry of the oceanic boundary layer by influencing the oxidising capacity through catalytically removing O3 and altering the HOx and NOx balance. The sea-to-air flux of iodine over the open ocean is therefore an important quantity in assessing these impacts on a global scale. This paper examines the effect of a number of r...

Fractals are commonly observed in nature and elucidating the mechanisms of fractal-related growth is a compelling issue for both fundamental science and technology. Here we report an in situ electron microscopy study of dynamic fractal growth of platinum during electrodeposition in a miniaturized electrochemical cell at varying growth conditions. Highly dendritic growth - either dense branching...