A MOF Multifunctional Cargo Vehicle for Reactive Gas Delivery and Catalysis

The use of magnesium-alloy stents shows promise as a less intrusive solution for the treatment of cardiovascular pathologies as a result of the high biocompatibility of the material and its intrinsic dissolution in body fluids. However, in addition to requiring innovative solutions in material choice and design, these stents also require a greater understanding of the manufacturing process to achieve the desired quality with improved productivity. The present study demonstrates the manufacturing steps for the realisation of biodegradable stents in AZ31 magnesium alloy. These steps include laser microcutting with a Q-switched fibre laser for the generation of the stent mesh and subsequent chemical etching for the cleaning of kerf and surface finish. Specifically, for the laser microcutting step, inert and reactive gas cutting conditions were compared. The effect of chemical etching on the reduction in material thickness, as well as on spatter removal, was also evaluated. Prototype stents were produced, and the material composition and surface quality were characterised. The potentialities of combining nanosecond laser microcutting and chemical etching are shown and discussed.

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The local Cauchy problem for ionized magnetized reactive gas mixtures

Mathematical Methods in the Applied Sciences ◽

10.1002/mma.629 ◽

2005 ◽

Vol 28 (14) ◽

pp. 1647-1672 ◽

Cited By ~ 2

Author(s):

Vincent Giovangigli ◽

Benjamin Graille

Keyword(s):

Cauchy Problem ◽

Gas Mixtures ◽

Reactive Gas

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Epitaxial Silicon Layers Made by Reduced Pressure/Temperature CVD

MRS Proceedings ◽

10.1557/proc-129-609 ◽

1988 ◽

Vol 129 ◽

Author(s):

J.L. Regolini ◽

D. Bensahel ◽

J. Mercier ◽

C. D'Anterroches ◽

A. Perio

Keyword(s):

Thermal Processing ◽

Atmospheric Pressure ◽

Rapid Thermal Processing ◽

Processing System ◽

Epitaxial Silicon ◽

Reduced Pressure ◽

Selective Epitaxial Growth ◽

Main Decomposition ◽

Rate Limiting ◽

Reactive Gas

ABSTRACTIn a rapid thermal processing system working at a total pressure of a few Torr, we have obtained selective epitaxial growth of silicon at temperatures as low as 650°C. When using SiH2Cl2 (DCS) as the reactive gas, no addition of HCl is needed. Nevertheless, using SiH4 below 950°C a small amount of HCl should be added.Some kinetic aspects of the two systems, DCS/HCI/H2 and SiH4/HCl/H2, are presented and discussed. For the DCS system, we show that the rate-limiting reactions are slightly different from those commonly accepted in the literature, where the results are from systems working at atmospheric pressure or in the 20-100 Torr range.Our model is based on the main decomposition of DCS, SiH2Cl→SiHCl + HCl, instead of the widely accepted reaction SiH2Cl2→SiCl2 + H2. This is the main reason why no extra HCl is required in the DCS/H2 system to obtain full selectivity from above 1000°C down to 650°C.

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