An apparatus for mounting a display screen to a printed circuit board. The setup request is then translated into packet network form and transmitted across a packet network. The apparatus also includes an inlet reaction mixture distribution manifold and an outlet polymerization reaction mixture collection manifold interconnecting the reactors for operation in parallel. By forming the operation unit including a microcomputer for communication on the drawer body 2, it becomes possible to increase the ceiling height of the drawer body 2, increase the ceiling height and capacity of the heating chamber 3, and enlarge the height limitation of an object to be cooked. When the grain boundary phase of the alumina-based sintered body is observed under a transmission electron microscope, and the weight ratio between an alkali metal component and the rare earth element component as reduced to oxides thereof alkali metalrare earth element is calculated at 30 circular spots, each having a diameter of 0.