Figure 1: Front view schematic of converted microwave ovens. Each oven is scaled to the US 4,804,431 patent oven, and for clarity, the auxiliary gas lines and vacuum systems outside the ovens are not shown. (a) Patent US 4,804, 431. (b) Replaceable reaction vessels. (c) Desiccator with a steel wire. (d) Three-port reaction flask fitted to door plus steel aerial electrode. (e) Coaxial narrow reaction tube. (f) Waveguide reactor.