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The irradiation of a steel surface in atmospheric pressure ambient was performed to study the surface nanostructuring resulting from the formation of a backward-deposited layer. The dynamics of the plume expansion and of the nanoparticle deposition process were investigated by in situ time-resolved optical analysis. Scanning electron microscopy and atomic force microscopy were employed to investigate the morphological characteristics of the backward deposited layer. The observations revealed a particular shape of plasma expansion. The latter is characterized by the formation of two vortices at the plasma plume periphery, where a high density of condensed nanoparticles are generated. It is shown that the surface nanostructuring is mainly due to a backward nanoparticles flux which leads to a deposition process during several tens of microseconds. The effects of laser wavelength on nanoparticle formation and surface nanostructuring are presented and discussed. [ABSTRACT FROM AUTHOR]

We have studied the structural properties of ZnO thin films grown on A1[sub 2]O[sub 3] (00.1) single-crystal substrates by pulsed-laser deposition using either a femtosecond or a nanosecond laser. Although hexagonal ZnO films deposited on sapphire substrate were epitaxially grown in both cases, the crystalline quality was found to be very different: ZnO films grown with the femtosecond laser are characterized by a higher mosaicity, a smaller crystallite size, a larger content of defects but also smaller residual stresses than ZnO films obtained by nanosecond laser ablation. These differences can be explained according to the kinetic energy of the species evolved during laser ablation as deduced from plasma characterization with a charged-coupled device camera: close to 1 KeV in the femtosecond regime for the population species emitted from the target with the highest velocity, versus a few hundreds of eV in the case of nanosecond pulses. The high energy species irradiation associated with a femtosecond laser is likely to induce a large structural disorder together with stress relaxation during ZnO films growth. Physics. [ABSTRACT FROM AUTHOR]

Presents a diagnostics of the early phase of an ultraviolet laser induced plasma through spectral line analysis, considering self-absorption. Information on the use of excimer lasers; Details on the experiment used in this presentation; Results of and discussion on the experiments.

Presents information on a study that investigated the nitriding technique of metals by means of laser induced plasma. Experimental details; Results and discussion on the study; Conclusion.

Presents a study that examined the plasma plume induced by pulsed carbon dioxide laser irradiation of a titanium target at power densities by emission spectroscopy. Details of the experiment; Results; Conclusion.

Deals with a study which explained the influence of ambient gas on the laser beam-metal surface energy transfer. Background to the study; Experimental setup; Details of the vaporization-initiated plasma breakdown mechanism.

Presents a study which examined laser-induced surface vaporization during the pulsed carbon dioxide laser irradiation of a titanium sample in an ambient gas. Experimental methods; Analysis of variation with helium pressure; Investigation of space-time evolution.

Focuses on a study which investigated vaporization and plasma formation resulting from excimer laser irradiation of titanium targets in a low-pressure nitrogen atmosphere. Experimental setup; Results and discussion; Conclusion.

Highlights: [•] Enriched eggs contain higher amount of n-3 fatty acids, lutein and zeaxanthin. [•] n-3 enriched egg can be spray dried without losses of fatty acids, moderate losses of antioxidants. [•] Lipid oxidation remains at a low level even after the different processing steps. [•] Whole egg powders contained higher quantities of malondialdehyde than egg yolk powders. [ABSTRACT FROM AUTHOR]

Thermal conductivity and thermal interface resistance of tungsten thin films were investigated by means of pulsed photothermal radiometry. The experimental system based on a nanosecond pulsed laser and a high-speed IR photodetector is presented. Calibration of the IR detector is described. The thermal properties of the samples are identified by comparison with an analytical solution of the heat transfer equation for layered samples already presented in the literature. The experimental system enables investigation of micron and sub-micron thick metallic films. The investigated films were deposited by magnetron sputtering on iron substrates using two different deposition conditions. The measured thermal conductivity values ranged from 40 to 62 W.m-1.K-1 and thermal contact resistances from 0.05 to 1.1 10-8 m2.K.W-1. [ABSTRACT FROM AUTHOR]

1. The roux plumage sex-linked recessive gene may be used for early sexing of Japanese quail in crossbreeding production systems with wild-type and roux lines. However, associated effects of the gene on carcase and meat composition need to be assessed. 2. Quail carcases from pure Line K males and females (100% K), a heavy meat line which was used as the recipient line for the introgression of the roux gene, and from same-age roux or wild-type females from the second generation of introgression (75% K) were dissected. The effects of sex, line and plumage colour on carcase components and on protein and lipid contents of various tissues were estimated. 3. Expected sex differences in carcase weights were obtained, with marginally higher values for females. However, weights of parts and carcase yield (ratio of empty carcase weight without head, neck and feet over live body weight) were similar for both sexes in pure Line K which had a 68% carcase yield. Lipid contents in leg meat were higher in males (3·1%) than in females (2·7%). 4. The roux gene did not seem to have any major impact on carcase parts or composition. However, in roux birds, leg skin was marginally higher in lipids and pectoralis major lower in proteins than in wild-type ones. [ABSTRACT FROM AUTHOR]

A micromachining technique for silicon deep anisotropic etching and isolating porous silicon structures is developed. This original method combines aluminum thermomigration and silicon electrochemical etching. In this way, we have generated high aspect ratio trenches and porous silicon isolating regions as well, through the entire thickness of the wafer. In order to evaluate our method, we performed etching rate measurements varying the current density. A maximum value of 22 μm/min has been already measured. The interest of the method in terms of cost and structures diversity is also justified. [ABSTRACT FROM AUTHOR]