Abstract: An apparatus for automated polyelectrolyte measurement in process materials comprises a sample vessel with an outer wall defining a cylindrical cavity and with a reservoir of larger diameter above and in communication with the cavity. A liner for the cavity and the reservoir are made of an electrically insulating material such as polytetrafluoroethylene. To clean the apparatus there is also provided an ultrasonic oscillator which is mechanically coupled to the sample vessel. In order to improve the cleaning process, the liner and preferably also the reservoir are attached to the outer wall in such a way as to resist tensile and shear forces and the ultrasonic oscillator is attached to the outer wall. Preferably, the liner is attached to the outer wall by an adhesive.

Abstract: A projector has a light source (1) for producing a parallel beam of white light (4); two dichroic prisms (21, 22) each having two dichroic colour-splitting layers, which on three of their sides have three liquid crystal light valve arrangements (23, 24, 25, 26, 27, 28) associated with different components of the color image; a lens (8) through which the color image components produced by the light valve arrangements (23 to 28) can be projected together on to a screen. The light valve arrangements (23 to 28) associated with the two dichroic prisms operate by reflection. Each of the two dichroic prisms (21, 22) is coupled with one of the outlets of a polarizing beam splitter (10), said outlets being associated with different polarizing directions. The polarizing beam splitter (10) distributes the beam of white light (4, 6) to the two dichroic prisms (21, 22) and directs the light of the activated image points travelling back from the two dichroic prisms into the lens (8).