The heats of adsorption on weakly activated ^-aluminium oxide for a number of linear alkanes (from n-butane to n-nonane) and for 2.2.4-trimethylpentane have been determined by GSC and extrapolated to zero surface coverage. The dependance of the adsorption energy on the number of carbon atoms is discussed on the basis of the bidimensional gas model: it is shown that the interactions of the adsor...

We present a new way of forming phononic crystal waveguides by coupling a series of line-defect resonators. The dispersion proprieties of these coupled resonator acoustic waveguides ͑CRAW͒ can be engineered by using their geometrical parameters. We show that single-mode guiding over a large bandwidth is possible in CRAW formed in a honeycomb-lattice phononic crystal slab of holes in zinc oxide. I...

We introduce spinning-disc Picometrology which is designed to measure complex refractive index of ultra-thin and size-limited sample deposited on a solid surface. Picometrology is applied to measure the refractive index of graphene on thermal oxide on silicon. The refractive index varies from ñg = 2.4-1.0i at 532 nm to ñg = 3.0-1.4i at 633 nm at room temperature. The dispersion is five times st...

We demonstrate widely tunable wavelength conversion based on four-wave mixing using a dispersion-shifted bismuth-oxide photonic crystal fiber (Bi-PCF). A 1-meter-long Bi-PCF is used as the nonlinear medium for wavelength conversion of a 10 Gb/s non-return-to-zero (NRZ) signal. A 3- dB working range of the converted signal over 35 nm is obtained with around 1-dB power penalty in the bit-error-ra...

The dynamic configuration of reduced graphene oxide (rGO) in an aqueous dispersion is revealed by several characterization methods, showing a spontaneous and seemingly irreversible configuration transition from flat to highly corrugated sheets over time. Such dynamic behaviour of rGO leads to a tailored porous structure of graphene-based thin films. This affects their permeation and electrochem...

We analyze the phase shift induced in an amplitude-modulated laser beam propagating through a water dispersion of graphene oxide sheets in a fiber-to-fiber U-bench. This phase shift arises from the thermally induced nonlinear refraction in the sample. The system exhibits strong optical limiting performance for weak continuous-wave signals. A theoretical model including beam propagation and ther...

Ellipsoid-shaped nanoclusters composed of single superparamagnetic nanoparticles can be generated by emulsion electrospinning. Stretching and subsequent solvent evaporation of iron oxide loaded emulsion droplets during the emulsion electrospinning process enables the creation of such structures embedded in polymer nanofibers. Dissolution of the polymer fibers yields an aqueous dispersion of the...

Large amounts of CO adsorption resulted from a pulse adsorption experiment at 323 K,giving ~300% Pt dispersion in the title catalyst.An in situ DRIFTS investigation showed that carbonate species on the Ce oxide surface are responsible for the CO adsorption, as a result of CO spillover. Lowering the temperature to 195 K reduced the amount of CO adsorption.The Pt particle size could be determined...

We experimentally study the temporal dynamics of amplitude-modulated laser beams propagating through a water dispersion of graphene oxide sheets in a fiber-to-fiber U-bench. Nonlinear refraction induced in the sample by thermal effects leads to both phase reversing of the transmitted signals and dynamic hysteresis in the input-output power curves. A theoretical model including beam propagation ...

Hazardous Material transportation by road is coupled with inherent risk of accidents causing loss of lives, grievous injuries, property losses and environmental damages. The most common type of hazmat road accident happens to be the releases (78%) of hazardous substances, followed by fires (28%), explosions (14%) and vapour/ gas clouds (6 %.). The paper is discussing initially the probable ‘Imp...