Abstract: An anti-smudge bar for a recorder is disclosed wherein the recorder has a drive means for advancing a strip chart in a longitudinal direction. The strip chart, as it advances, passes over a platen disposed upstream of the advancing means. A pressure roller adjacent the upstream side of the platen presses the strip against the platen. The pressure roller has a plurality of longitudinal grooves spaced by sharp crests which contact the chart in a manner preventing smudging of wet ink traces previously recorded on the chart. The ink traces are recorded on the chart by a recording pen which is movable in a direction transverse to the direction of chart movement. The roller and the pen are lifted from chart contact whenever the chart direction is reversed to permit subsequent recording on a chart segment previously recorded on.

Abstract: A correction system is disclosed for double-beam spectrophotometers of the optical nulling type in which a mechanical radiation attenuator is positionally adjusted in the path of the reference beam by means of an error signal proportional to the detected difference in intensity and between the sample and reference beams. The attenuator takes the form of a circular sector mounted for angular displacement about an axis through the sector circle center by a servomotor in response to the error signal. The sector contains one or more wedge-shaped apertures arcuately disposed about said center so that the reference beam passes through the apertures and is partially (or totally) occluded in accordance with the angular position of the sector.

Abstract: A deposit of a reinforcing material is formed on an aluminium alloy piston by spraying one or more regions of the piston with a copper-based material from an electric-arc spray gun which produces molten particles of a heat content sufficient to produce an effective metallurgical interaction with the piston alloy so that the copper-based material is bonded to the region or regions of the piston.