Abstract: A limiting current-type oxygen sensor including (a) an oxygen ion-permeable substrate made of a zirconia solid electrolyte having a gas diffusion pore extending between first and second surfaces of the substrate for rate determination by oxygen diffusion through the pore; (b) a first porous electrode formed on the first surface of the substrate in an area including an opening of the gas diffusion pore; (c) a second porous electrode formed on the second surface of the substrate such that it is opposite to the first porous electrode via the substrate; (d) a sealing member fixed to the second surface of the substrate for sealing the second porous electrode such that the internal chamber is defined on the second porous electrode; and (e) a heating means mounted to the sealing member.

Abstract: The tunneling scanning microscope which is provided with a light source to irradiate a sample with light, particularly with light having one wavelength. The apparatus is used for the investigation of the surface structure of materials which have very low conductivity but increase their conductivities under light irradiation. In particular, the apparatus selectively provides an atomic image of an element of a compound in response to a selected wavelength.

Abstract: An alumina-zirconia-silicon carbide sintered ceramic composite having high strength and high hardness is composed of 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 .mu.m, 3 to 40 volume percent of silicon carbide powder of mean particle size smaller than 1 .mu.m or silicon carbide whiskers of 1 .mu.m or less in diameter with an aspect ratio between 3 and 200 or combination of said silicon carbide powder and said silicon carbide whiskers, the balance being substantially alumina powder, wherein zirconia plus silicon carbide accounts for 55 volume percent at most of the total.The sintered ceramic composite is manufactured by making a mixed powder composed of 5 to 50 volume percent of partially stabilized zirconia powder of mean particle size between 0.1 and 1.0 .mu.m, 3 to 40 volume percent of silicon carbide powder of mean particle size smaller than 1 .mu.m or silicon carbide whiskers of 1 .mu.