Abstract: Provided is an oral composition for denture wearers, which includes an antimicrobial substance of biological origin, is biocompatible, and has an antimicrobial activity. Specifically, provided is an antimicrobial oral composition for denture wearers including a component of common rush origin. The oral composition for denture wearers is placed in the mouth, and hence the oral composition for denture wearers including a component of common rush origin, which may also be used as a food additive, is safe for a living body and useful.

Abstract: Method and apparatus for controlling the cooling of a hermetic type control box accommodating therein electronic apparatus by means of a cooling system. A cooling member of the cooling system is disposed at an upper portion of a hermetically closed chamber in which the electronic apparatus is housed. On the basis of measurements of intra-box temperature and extra-box temperature, control is so performed that the intra-box temperature is maintained higher than the extra-box temperature by a predetermined value when the cooling is being effected within the control box by means of the cooling system.

Abstract: A double-beam spectrophotometer comprising a light source, a monochromator, optical means for causing the monochromatic light beam from the monochromator to alternately advance along a pair of optical paths, the axes of which intersect generally perpendicularly to each other, a pair of cells each disposed in one of the two optical paths, and a photoelectric detector disposed at or adjacent the point of intersection of the pair of optical paths.

Abstract: A spectrophotometer which can be used selectively as a single-beam and a double-beam type and comprises a light source, a monochromator, a chopper mirror for causing the monochromatic light beam from the monochromator to alternately advance along a first and a second path, in which a reference and a sample cell are disposed respectively, a beam combiner for causing the alternate beams to advance along a common path leading to a photoelectric detector, and a mirror movable for selective positioning in and out of the monochromatic light beam between the monochromator and the chopper mirror.

Abstract: A detector for use in optical measuring instruments such as a double-beam spectrophotometer, comprising a photoelectric element having a photosensitive surface and a beam mixer disposed adjacent the photosensitive surface for causing each of two alternate light beams to be projected evenly and uniformly onto the photosensitive surface of the photoelectric element thereby to eliminate errors which would otherwise be caused in the result of measurement due to local difference in sensitivity of the photosensitive surface of the photoelectric element. The beam mixer comprises a symmetrical pair of light diffusing plates so arranged as to form a roof-shaped configuration and a tublar body having one end opening closed by the pair of light diffusing plates and the opposite end opening closed by the photosensitive surface of the photoelectric element.