Showing papers by "Gilles Flamant published in 1996"
TL;DR: In this article, a short survey of the vaporization-condensation method used in the Odeillo (France) solar furnace is presented. And the authors discuss some of the growth mechanisms of these molecules and possible ways to increase the yield, reaching 20% in the best cases.
Abstract: We have shown previously that the high intensity of solar radiation obtained with the Odeillo (France) solar furnace facilities, can be used to vaporize graphite in an inert-gas atmosphere and to produce fullerenes. After a short survey of the vaporization - condensation method used here, we discuss some of the growth mechanisms of these molecules and possible ways to increase the yield, which can reach 20% in the best cases. These experiments point out the principal factors controlling the fullerene yield, such as temperature, pressure and the gas flow rate of the inert gas or the density of carbon atoms in the vaporization zone. Using these observations, the next developments of the method are currently in preparation using a 1 MW solar furnace.
31 citations
TL;DR: In this paper, a set of pyrometers was developed for monitoring real-time thermocycles in laser materials processing, where the combination of high speed (sampling time 20-50 μs), wide temperature range (800-4700 K), and spatial resolution (300-400 μm) provided the means for precise analysis of surface temperature dynamics.
25 citations
TL;DR: In this article, the synthesis of ultrafine particles as a result of condensation in an erosive jet at laser vaporization of materials (metals, metal oxides, carbon) in gases (hydrogen, oxygen, helium, argon, xenon and air) at high pressures is investigated.
17 citations
TL;DR: In this article, the influence of the laser radiation wavelength and the choice of the diameter of the initial high-temperature region in the gas phase (i.e., the region of optical breakdown) on the laser plasma dynamics and the transfer of laser and plasma radiation energy to the target are analyzed.
16 citations
TL;DR: In this paper, the authors discussed the possibility of increasing the evaporation of graphite and the yield of soot with this technique, and obtained an estimate of the soluble fullerene yield which varies with the pressure and can reach 18% and showed that 13 C-enriched fullerenes can be easily produced by this process.
10 citations
TL;DR: In this article, the influence of the electron structure of atoms shells on the threshold intensity and breakdown period of a metal vapour was analyzed by making use of the collision-radiative model.
2 citations
15 Jul 1996
1 citations