Abstract: A method for manufacturing a surface-treated gas-phase-process silica particle, the method including steps of: adding 1,3-divinyl-1,1,3,3-tetramethyldisilazane to a raw material gas-phase-process silica particle and introducing a vinyldimethylsilyl group on a surface of the raw material gas-phase-process silica particle to obtain a preliminarily treated silica particle; and adding hexamethyldisilazane to the preliminarily treated silica particle and introducing a trimethylsilyl group on a surface of the preliminarily treated silica particle to obtain a surface-treated gas-phase-process silica particle.

Abstract: A column jacket includes a hollow outer jacket having a pair of clamped portions disposed to sandwich a slit between the clamped portions and a tubular inner jacket having, in an area where the inner jacket is fitted in the outer jacket, an elongated hole extending in an axial direction. A clamping mechanism clamps the pair of clamped portions with a pair of side plates of a fixed bracket. The elongated hole is disposed on any one of a first side and a second side, in the lateral direction, of a vertical plane passing through a central axis of the inner jacket, at a position other than on a straight line that extends in a vertical direction through the central axis.

Abstract: A column jacket includes a hollow outer jacket having a pair of clamped portions disposed to sandwich a slit between the clamped portions and a tubular inner jacket having, in an area where the inner jacket is fitted in the outer jacket, an elongated hole extending in an axial direction. A clamping mechanism clamps the pair of clamped portions with a pair of side plates of a fixed bracket. The elongated hole is disposed on any one of a first side and a second side, in the lateral direction, of a vertical plane passing through a central axis of the inner jacket, at a position other than on a straight line that extends in a vertical direction through the central axis.