This invention relates to a preparation method and equipment of graphite and catalyst composite for a kind of synthetic diamond. The electrolyte membrane for solid oxide fuel cells includes two or more deposited layers, wherein each of the deposited layers independently has an average crystal grain size of 5-100 nm and the deposited layers are different from each other in the average crystal grain. Cutting elements may comprise multi-layer diamond tables that result in the formation of a shear lip during cutting. The coupled lines are connected to an input port and two balanced output ports. Furthermore, the first routing statement contains a cross-reference to a further routing statement.