basic crystal structure this powder was slurried or dissolved in a liquid for example freon liquid or an alcohol such as ethanol or another liquid this liquid was poured into the hollow support body or metal pipe 2 shown in fig1 which is made of for example copper or a copper compound such as a nicu compound with the other end of the pipe blocked the inner wall surface of the pipe 2 was coated to a uniform thickness with the ceramic powder by rotating and turning the pipe 2 from end to end so that the powder adhered to the wall while the pipe 2 was completely heated to a temperature at 100 u00b0 c to 400 u00b0 c in this way the solvent was removed from the inside of the pipe 2 and the inner wall surface received a ceramic powder coating 3 to make the coating adhere more tightly to the inner wall surface a solvent which dissolves epoxy or acrylic resins for example toluene or the like may be used after this oxygen or a mixture of oxygen and argon gas is introduced into the hollow section over the dried ceramic material adhered to the inner wall surface and the ceramic material is fired while it is being oxidized at 500 u00b0 c to 1100 u00b0 c for example at 600 u00b0 c for 3 hours and additionally at 800 u00b0 c for 5 hours by repeating this type of process 1 to 5 times the ceramic material was adhered to the inside of the pipe to an average.