Abstract: There is disclosed a high dielectric constant material which comprises a composite material comprising at least one of BaO and CaO; PbO; Fe.sub.2 O.sub.3 ; Nb.sub.2 O.sub.5 ; WO.sub.3 and CuO, said composite material being represented by the general formula:xPb(Fe.sub.1/2 Nb.sub.1/2 l )O.sub.3 -yM(Cu.sub.1/2 W.sub.1/2 )O.sub.3 -zPb(Fe.sub.2/3 W.sub.1/3 )O.sub.3wherein M is at least one of Ba and Ca, and x, y and z are defined in the specification.The disclosed dielectric material can also contain 0 to 1.0% by weight, relative to said composite material, of manganese oxide.

Abstract: A humidity-sensitive element comprises a humidity-sensitive body which includes 21-73 mol % of Cr.sub.2 O.sub.3, 25-55 mol % of at least one member selected from the group consisting of ZnO and MgO, 0.5-8.0 mol % of CuO, 0.5-8.0 mol % of Li.sub.2 O, and 0.5-8.0 mol % of V.sub.2 O.sub.5, and a pair of electrodes attached to the body. Such an element provides excellent stability over a wide range of humidity and temperature levels.

Abstract: A humidity-sensitive element which has excellent humidity-sensitive characteristics and has a small drift after being exposed to a high humidity for a long period of time. The humidity-sensitive element of the invention includes a porous metal oxide sintered body, a simple substance or an oxide of phosphorus or sulfur carried on the porous metal oxide sintered body, and copper ions carried on the porous metal oxide sintered body.

Abstract: A cation emission type halogenated hydrocarbon gas detecting element comprising a cation source, a heating means and an ion collector electrode, which is characterized in that said cation source consist essentially of .beta.-Al.sub.2 O.sub.3, wherein substantially all cation species occupy a position in the crystal lattice structure of the source. By employing .beta.-Al.sub.2 O.sub.3, the detecting element can be more miniaturized and can work at lower temperature than a conventional cation emission type electrode comprising the cation source made of steatite.

Abstract: Disclosed is a gas leak detector comprising; a tubular gas-sensitive element defining openings at both ends thereof, one end being a gas inlet and the other end a gas outlet, and made of an oxygen-ion conductive solid electrolyte; a set of electrodes provided respectively on the inner and outer walls of the gas-sensitive element, the electrode on the outer wall being kept in contact with a reference gas; a heater adapted to heat the gas-sensitive element to a predetermined temperature at a location corresponding to the set of electrodes; and a catalytic layer provided on the surface of the electrode on the inner wall being kept in contact with a target gas.

Abstract: A moisture sensitive element for detecting humidity variations through sensing variations in electric resistance using a porous metal oxide ceramic. At least either phorphorus or sulfur is incorporated in and supported by the porous metal oxide ceramic with the phosphorus or sulfur being applied in either a pure or oxide form.

Abstract: A unit for measuring the alkali metal vapor concentration of a gaseous phase, comprisinga gas inlet pipe,a container provided with a heating means for vaporizing the alkali metal mist contained in the gas, and a .beta.-alumina sensor serving to measure the alkali metal vapor concentration,a vapor trap connected to the container via a gas conduit and serving to condense and remove the alkali metal vapor contained in the gas,a gas pump having the suction port connected to the vapor trap via a gas conduit, anda gas discharge pipe connected to the discharge port of the gas pump.The unit can be mounted anywhere and is easy to handle and operate.