A composition for removing hydrogen from an atmosphere, comprising a mixture of a polyphenyl ether and a hydrogenation catalyst, preferably a precious metal catalyst, and most preferably platinum, is disclosed. Preferred polymers are organic, e. A space permitting air flow is present between a portion closest to the axis of at least one of the plurality of blades and the axis. A half-wave plate or the like is positioned in the laser beam path to rotate the plane of polarization of the laser beam so that it is aligned with the path of particles before it irradiated particles moving along such path. A multiplicity of deflector electrodes may be located between the target and grid to enhance shaping of the electric field. The closure cap is provided with a bottom and the closure stopper is formed on the inner side of the cap bottom opposite the neck opening.