Abstract: A microspherical packing for liquid chromatography, which comprises a porous silicon carbide having numerous through-pores, and a process for producing said microspherical packing.

Abstract: A solid pole oxygen sensor having a solid pole, in which one end of a lead wire of platinum or platinum rhodium is buried, tightly covered by a solid electrolyte and pressure-molded into a circular plate, which is dried and then fired in a reducing atmosphere. The surface of a sintered mass thus obtained is plated or baked to form a platinum electrode, and the oxygen sensor element thus obtained is secured by a bonding agent to the tip of a cylindrical ceramic insulator having electroconductive zones to be connected to the platinum electrode in such a manner that the circular face of the circular plate-shaped oxygen sensor element is in contact with the tip surface of the cylindrical ceramic insulator.

Abstract: An oxygen sensing element capable of measuring partial pressures of oxygen in sample gases, which element has a solid electrolyte member having totally embedded therein a means for providing a reference partial pressure of oxygen composed of a sintered product of a finely divided metal or metal-metal oxide mixture and having a lead-out wire connected thereto is prepared by a method wherein: p1 (a) a part of the finely divided solid electrolyte material is compression-molded to form a provisional solid electrolyte member having a hole;(b) a provisional product of the reference oxygen partial pressure-providing means is formed in the hole of the provisional solid electrolyte member from the finely divided metal or metal-metal oxide mixture;(c) the remaining part of the finely divided solid electrolyte material is piled up on the provisional reference oxygen partial pressure-providing means product, followed by compression molding the piled up solid electrolyte material to form an integrated structure comprising

Abstract: A solid pole oxygen sensor in which one end of a lead wire of platinum or platinum/rhodium is buried in a solid pole and the surfaces of the solid pole and the lead wire are coated with an electroconductive paste. The solid pole is wrapped or encased in a solid electrolyte, pressure-molded into a pellet, which is dried and then fired in a reducing atmosphere. The surface of the sintered mass thus obtained is then plated or baked to form a platinum electrode, and the oxygen sensor element thus obtained is fitted or secured to the tip of an approximately cylindrical ceramic insulator equipped with electroconductive zones to be connected to the platinum electrode.

Abstract: A solid pole oxygen sensor wherein an oxygen sensor element is composed of a solid pole with one end of a lead wire buried therein; an internal electrode formed on the outside surface of the solid pole; a solid electrolyte enclosing the electrode to constitute a solid pole assembly as a column with a projection at its top; and a platinum electrode separated from the lead wire. The oxygen sensor element is so secured to an almost cylindrical ceramic insulator by means of adhesive or the like that the upper top side of the oxygen sensor element having the projection is matched to a recess at the tip of the cylindrical ceramic insulator and a pair of electroconductive zones provided on the side wall of the cylindrical ceramic insulator are electrically connected with the platinum electrode and the lead wire. A process of manufacturing a solid oxygen sensor is also disclosed.

Abstract: A protective layer of a refractory material deposited on a metal electrode layer of an oxygen sensing element is improved by a process comprising forming the protective layer onto the surface of the metal electrode layer by plasma spray coating the surface of the metal electrode layer, first with a refractory material powder at a position of a prescribed distance from a plasma spray coating device and at a prescribed electric power, and second, with a refractory material powder having the same particle size and composition as said refractory material powder used in the first plasma spray coating at a position of a distance greater than said prescribed distance and/or at an electric power lower than said prescribed electric power.

Abstract: Low temperature operability of an oxygen sensing element, which comprises a solid electrolyte member composed of sintered material, and a means for providing a reference oxygen partial pressure, composed of a sintered product of a finely divided metal or metal-metal oxide mixture powder and being completely embedded within the solid electrolyte member, is improved by the incorporation of from 0.5 to 10% by weight, based on the total weight of the sintered product, of a finely divided platinum group metal powder in the sintered product of the reference oxygen partial pressure-providing means.

Abstract: The high temperature durability of an oxygen sensing element, which comprises a solid electrolyte member composed of sintered material, and a means for providing a reference oxygen partial pressure, composed of a sintered product of a finely divided metal or metal-metal oxide mixture powder and being completely embedded within the solid electrolyte member, is improved by incorporating in the finely divided metal or metal-metal oxide mixture powder an antisintering material and a pore-forming material capable of subliming or being decomposed, thereby to generate gas upon sintering. The amounts of the antisintering material and the pore-forming material are from 5 to 70% by weight and from 20 to 80% by weight, respectively, based on the total weight of these additives-incorporated metal or metal-metal oxide mixture. The low temperature operation capability of the oxygen sensing element is improved by further incorporating therein a minor amount of a platinum group metal.