Abstract: A method of purifying 1,3-bis(3-aminopropyl)-1,1,3,3-tetraorganodisiloxane represented by the formula (I) as described hereinbefore, which comprises recrystallizing a crude product of the compound as its acid addition salt, and then neutralizing the acid addition salt to obtain a purified product of the compound. According to the method of the present invention, the compound of the formula (I) can be purified at high purity in high yield, and the purification treatment can be industrially conducted.

Abstract: A horizontal synchronizing reference signal producing circuit produces an internal horizontal synchronizing reference based upon an inputted clock and a reset pulse, a phase comparator compares the phases of a given external horizontal synchronizing reference and an internal horizontal synchronizing reference outputted by the horizontal synchronizing reference and generates a voltage signal conforming to a difference between the two compared phases. A low-pass filter then passes low-frequency components of the voltage signal outputted by the phase comparator, a VCO, whose frequency is controlled by an output voltage signal from the low-pass filter, generates a clock applied to the horizontal synchronizing reference signal producing circuit, a decision circuit determines whether the phase difference between the internal and external horizontal synchronizing reference signal lies within a range in which follow up is capable of being performed by the VCO.

Abstract: An image quality correction circuit for use with an imaging apparatus which converts a luminance signal so that an intermediate portion of the signal between preset minimum and maximum values is extended. The invention also relates to a device where color difference signals are corrected in accordance with the same nonlinear characteristic utilized in the correction of the luminance signal.

Abstract: Handling of catalytic reduction catalyst elements used for denitration can be facilitated. The catalyst elements are changed in a basket comprising a hollow body which is made of steel so as to permit the passage therethrough of exhast gases from one end to the other end thereof, a catalyst element supporting member which is disposed at the bottom of said hollow body, upon which are placed the catalyst elements and which is adapted to permit the passage of exhaust gases therethrough, and ceramic shock absorbers interposed between the inner surfaces of the hollow body, and the catalyst elements charged therein. The catalyst elements charged in each basket can be handled as a unit and placed upon shelves disposed in an exhaust gas passage.