Abstract: In an ionization chamber detector of the type in which a plurality of flat anode and cathode electrodes are alternately arranged in a predetermined gaseous medium, this invention provides a method of producing an ionization chamber detector which is characterized in that a plurality of ditches having a width a little bit greater than the thickness of the electrodes are formed on the inner surfaces of a pair of insulators disposed in the spaced-apart relation for supporting and fixing the anode and cathode electrodes, an adhesive is applied in advance temporarily in a rectangular form to both or one surface of each electrode at those positions which are set back by a distance corresponding to the thickness of the electrodes from both edge portions, another adhesive having a low viscosity is charged from the end portions of the ditches into the gaps between the electrodes and the ditch walls after the electrodes are inserted into the ditches, and the tentative adhesive and the adhesive having a low viscosity ar

Abstract: A multi-cell radiation detector constructed such that a first group of electrodes to which is applied high voltage and a second group of electrodes to which are connected signal leads are alternately arranged inside a vessel containing ionizable gas enclosed therein. The first group electrodes are provided with terminals to which are connected leads for introducing high voltage from the exterior, while the second group electrodes are provided with terminals to which are connected leads for leading out signal outputs to the exterior. These leads and terminals are all disposed at positions offset from traveling path of the radiation so as to reduce the volume of the space under the weak electric field behind the electrode section.

Abstract: A radiation detecting apparatus includes a pair of substrates disposed face to face in such a manner that a plurality of grooves provided in one of the facing surfaces at a predetermined interval face a plurality of grooves provided in the other of the facing surfaces at the predetermined interval. Radiation shielding plates are inserted at both ends thereof into a facing pair of grooves to be held by both of the substrates, scintillators are mounted on a corresponding one of the radiation shielding plates, and photodetectors are fixed to either one of the facing surfaces of the substrates between adjacent grooves so that a plurality of facing pairs of photodetectors are juxtaposed.

Abstract: A process for metal plating a stainless steel comprising the first step of treating the stainless steel by a cathode electrolysis in an aqueous solution containing free HCl in an amount at least 30 g/l and at least one species of Ni and Co in an amount at least 0.1 g/l; the second step of metal plating the same by Ni or a Ni alloy in a weakly acidic Ni plating bath; and the third step of subsequently plating the same by a noble metal, Cu or an alloy thereof.

Abstract: In a system in which the tomographic image of an object under investigation is produced on the basis of the amount of absorption of radiation by the object when a source of radiation and a plurality of radiation sensitive detectors with the object interposed therebetween are rotated around the object, the output signal from at least one of the plural detectors is used to correct the radiation absorption amount. Another selected one of the plural detectors may be used for checking whether the object is positioned within a useful detection view.

Abstract: A tomographic imaging system is disclosed in which the quantity of absorption or transmittance of a transmissive radiation by or through a certain tomographic cross-section of an object under consideration is detected and the distribution of radiation absorption or transmittance in the cross-section is reconstructed through a convolution operation. A weighting function used in the convolution operation is prepared with a predetermined one of its positive orders the value of which is an integration of the weighting function from the predetermined positive order to positive infinity and a predetermined one of its negative orders the value of which is in integration of the weighting function from the predetermined negative order to negative infinity.