Abstract: A total hip replacement type artificial joint comprising a stem and a socket, the stem being provided with a head at the upper end thereof and comprising a porous portion as an upper portion, a protector located under and along the porous portion and at the same height as the porous surface of the porous portion, an intermediate portion which underlies the porous portion and which is trapezoidal in section, and a lower portion which underlies the intermediate portion and which is circular in section, and the socket comprising an outer cup and a protector, the protector being provided along the outer peripheral edge of the outer cup and at the same height as a porous surface formed on the outer surface of the outer cup.

Abstract: An electrochemical gas sensor includes, as disposed on an insulating substrate, a plurality of electrodes for individually sensing a standard gas present in a surrounding atmosphere at a fixed concentration and a target gas present in the surrounding atmosphere, and a signal processing circuit for determining sensor life on the basis of sensed outputs of the standard gas. Constant detection of the sensitivity characteristics of the gas sensor is thereby attained for self-examination of the life thereof.

Abstract: An electrochemical gas sensor comprises an insulating substrate, active and counter electrodes disposed on a surface of the insulating substrate mutually spaced to have respectively reactive portions, a reference electrode spaced from the active and counter electrodes and having a reactive portion, and a solid electrolyte layer formed to cover the reactive portions of the active, counter and reference electrodes, whereby the sensitivity to gases of the active electrode is improved and stabilized.

Abstract: An excellent optical fiber built-in type composite insulator including at least two insulator bodies each having a penetration bore, at least one optical fiber inserted in the penetration bores, and sealing structures for the penetration bores of the insulator bodies and for a joining layer of opposing end surfaces of adjacent insulator bodies, is provided, which effectively prevents leakage of inner silicone grease, bending and breakage of the optical fiber, leakage of electric current along the penetration bores, short circuited trouble, and destruction of the insulator bodies, improves joining strength of the opposing end surfaces of the insulator bodies, and maintains the joining strength for a long period, affords a change of numbers of the insulator bodies, and facilitates the production. A method of producing such composite insulator is also provided.

Abstract: An excellent optical fiber built-in type composite insulator including at least two insulator bodies each having a penetration bore, at least one optical fiber inserted in the penetration bores, and sealing structures for the penetration bores of the insulator bodies and for a joining layer of opposing end surfaces of adjacent insulator bodies, is provided, which effectively prevents leakage of inner silicone grease, bending and breakage of the optical fiber, leakage of electric current along the penetration bores, short circuited trouble, and destruction of the insulator bodies, improves joining strength of the opposing end surfaces of the insulator bodies, and maintains the joining strength for a long period, affords a change of numbers of the insulator bodies, and facilitates the production. A method of producing such composite insulator is also provided.

Abstract: An olefin polymerization catalyst component subjected to successive preliminary polymerization treatment using each of a straight chain alpha-olefin having 2 to 5 carbon atoms and 3-methyl-1-butene; an olefin polymerization catalyst using the olefin polymerization catalyst component; a process for polymerizing olefin(s) which comprises polymerizing or copolymerizing olefin(s) in the presence of the olefin polymerization catalyst; and a film and an injection-molded article of polypropylene which is prepared by the process are also provided.