Abstract: A pneumatic manifold which can be constructed using standard PCB (Printed Circuit Board) construction techniques provides customised flow distribution around (and/or between) different members. By virtue of its PCB construction the manifold also may include conductive electrical tracks and fixing points common to other PCBs and possibly serving electrical pneumatic components.

Abstract: A demountable pellet is disclosed for use as an electrode contact assembly. The pellet comprises a base 1 upon which is mounted a plurality of electrodes 18, 19, 20 arranged in respective spaced parallel planes and having respective contacts 23, 24, 25 protruding from them. A closure 2 for the base 1 has a member 11, 12, 13 engaging at least one of the electrode contacts. In an unassembled condition of the pellet, with the closure 2 separate from the base 1 and each closure member disengaged from its respective electrode contact, the contacts 23, 24, 25 lie in respective spaced parallel planes. In the assembled condition of the pellet with each closure member engaging its respective electrode contact, at least one of the contacts 23, 24, 25 lies in a plane other than that in which it lay in the unassembled condition of the pellet.

Abstract: A demountable pellet is disclosed for use as an electrode contact assembly. The pellet comprises a base 1 upon which is mounted a plurality of electrodes 18, 19, 20 arranged in respective spaced parallel planes and having respective contacts 23, 24, 25 protruding from them. A closure 2 for the base 1 has a member 11, 12, 13 engaging at least one of the electrode contacts. In an unassembled condition of the pellet, with the closure 2 separate from the base 1 and each closure member disengaged from its respective electrode contact, the contacts 23, 24, 25 lie in respective spaced parallel planes. In the assembled condition of the pellet with each closure member engaging its respective electrode contact, at least one of the contacts 23, 24, 25 lies in a plane other than that in which it lay in the unassembled condition of the pellet.

Abstract: An ionization detector includes a third (fence) electrode (55) between the counter electrode (53) and the sensing electrode (54). The fence electrode (53) is maintained at or near the potential of the sensing electrode (54) and traps charge movement (electrolytic current) along the detector walls associated with condensation and/or contamination within the detector. In a photoionisation detector, the fence electrode is also adapted to trap photo-induced current originating from the cathode (53). Current drawn from the fence electrode (53) provides a measure of the degree of contamination or condensation within the detector and of lamp efficiency.

Abstract: An ionisation detector includes a third (fence) electrode (55) between the counter electrode (53) and the sensing electrode (54). The fence electrode (53) is maintained at or near the potential of the sensing electrode (54) and traps charge movement (electrolytic current) along the detector walls associated with condensation and/or contamination within the detector. In a photoionisation detector, the fence electrode is also adapted to trap photo-induced current originating from the cathode (53).