Abstract: An oxygen sensor comprises a solid electrolyte having one surface covered with a porous metallic film and the other surface on which a sinter of a metal and an oxide of the metal is disposed. Electromotive force (EMF) is developed between the film and the sinter during its use.

Abstract: A first layer of a metal/metal oxide sinter which acts as a reference source of oxygen is affixed on a flat surface of a base member, a second layer of solid electrolyte is affixed on the first layer and a third layer of metal is affixed on the second layer so that upon exposure of the third layer to exhaust gases or the like, an EMF (electromotive force) is developed between the first and third layers.

Abstract: An oxygen sensor made up of an oxygen concentration cell which as a stratiform structure and includes a thin film of an oxygen ion conductive solid electrolyte and a thin layer of a material serving as the source of a reference oxygen partial pressure such as a Ni-NiO system, an electrically nonconductive base plate which supports thereon the cell, and a thin metal layer embedded in the base plate as a resistance heating element for heating the solid electrolyte film.

Abstract: A high temperature abrasion-resistant material in the form of a sintered mass such as a board consists of NiO and/or CoO, Ni and/or Co, and a solid lubricant such as CaF.sub.2. The concentration of the total oxide in the mass is maximum at the surface and continuously decreases as the depth from the surface increases, but the concentration of the total metal is substantially zero at the surface and continuously increases as the depth increases. The lubricant is uniformly distributed. This material is produced by firstly sintering a powder mixture of the ingredients in a non-oxidizing atmosphere into a mass of a desired shape and subsequently heating the sintered mass in an oxidizing atmosphere.

Abstract: A porous coating, which is effective in restricting the flow of a gas under measurement relatively to the electrode layer of the sensor and protecting the electrode against detrimental influences, is formed by spraying fine particles of a heat-resistant and chemically stable material at a high temperature onto the electrode surface to form a porous layer with pores of a moderate size, then impregnating the porous layer with an aqueous dispersion of fine particles of a similar material followed by baking the impregnated layer, so that the finished coating has pores of appropriate size and total volume.

Abstract: In an oxygen sensor having a solid electrolyte layer such as stabilized zirconia and two electrode layers form respectively on both sides of the electrolyte layer, at least one electrode which is to be exposed to a gas mixture subject to measurement is made of carbon silicide to avoid catalyzing oxidation reactions, optionally with the addition of a minor amount of trisilicon tetranitride as a binder. The sensor features an exact and noticeable dependence of its output voltage on the oxygen concentration in a gas mixture in a non-equilibrated state as typified by an engine exhaust gas.

Abstract: A plurality of corrugated sheets are fixedly superimposed one on another so that the axes of the corrugations of one sheet are not parallel to those at adjacent sheets.

Abstract: A method for extraction of acrylic acid and/or methacrylic acid from a solution containing the same by treating the said solution with an organic solvent, which is characterized by using a mixture of methylethylketone and a xylene as the organic solvent. By such method, the extraction of acrylic acid and/or methacrylic acid is accomplished efficiently and economically.

Abstract: An electrode of an oxygen sensor of the concentration cell type is made of a material such as Au or a Pt/Pb/S mixture, which material is devoid of catalytic oxidizing effect on CO and HC in an engine exhaust gas, so that the EMF characteristics depend on actual O.sub.2 concentrations.

Abstract: One of the Pt electrodes of a concentration cell comprising a solid oxygen-ion electrolyte is coated with a porous inorganic material such as .gamma.-type Al.sub.2 O.sub.3 impregnated with an oxidation catalyst such as Pt so that oxidation reactions in a mixed gas to be measured may attain equilibrium before the gas comes into contact with the cell.