Abstract: The invention relates to a module for a parallel tester for the testing of circuit boards, and to a parallel tester comprising such modules. The modules have circuit boards standing at right-angles to the plane of the basic grid of the parallel tester, and on which contact pins are arranged along one side edge. The contact pins lie with their peripheral surfaces on flat sides of the circuit boards and protrude a short distance beyond the side edge of the circuit board. They are connected electrically and physically to contact fields formed on the circuit board. This arrangement of the contact pins is cost-effective to produce, mechanically stable, and permits the production of modules with a high density of contact pins.

Abstract: The invention relates to a module for a parallel tester for the testing of circuit boards, and to a parallel tester comprising such modules. The modules have circuit boards standing at right-angles to the plane of the basic grid of the parallel tester, and on which contact pins are arranged along one side edge. The contact pins lie with their peripheral surfaces on flat sides of the circuit boards and protrude a short distance beyond the side edge of the circuit board. They are connected electrically and physically to contact fields formed on the circuit board. This arrangement of the contact pins is cost-effective to produce, mechanically stable, and permits the production of modules with a high density of contact pins.

Abstract: The present invention relates to a process for preparing gel-like anion exchangers by aminating crosslinked gel-like styrene divinybenzene bead polymers that contain halogenoalkyl groups in the presence of an inorganic salt and in the absence of organic solvents.

Abstract: 2,3,4,5-tetrafluorobenzene derivatives can be obtained in a particularly advantageous manner by reacting the corresponding chlorobenzene or (chloro, fluoro)-benzene derivatives with a fluorinating agent in the presence of a solvent and a catalyst at elevated temperature, which comprises carrying out the reaction initially under temperature and pressure conditions such that the respective 2,3,4,5-tetrafluoro-benzene derivative continuously distills off through a column, and subsequently setting temperature and pressure conditions such that residual fractions of the 2,3,4,5-tetrafluorobenzene derivative distill off with the corresponding 2,3,4-trifluoro-5-chloro compound.

Abstract: The invention relates to a process for the preparation of diaminodicyclohexylmethane (“PACM”) with a proportion of trans,trans-4,4′-diaminodicyclohexylmethane of from 17 to 24% by hydrogenation of diaminodiphenylmethane (“MDA”) in the presence of a pulverulent catalyst in a continuously operated suspension reactor at a conversion of MDA of at least 95%, based on the amount of MDA used.

Abstract: The invention relates to a process for the preparation of diaminodicyclohexylmethane (“PACM”) with a proportion of trans,trans-4,4′-diaminodicyclohexylmethane of from 17 to 24% by hydrogenation of diaminodiphenylmethane (“MDA”) in the presence of a pulverulent catalyst in a continuously operated suspension reactor at a conversion of MDA of at least 95%, based on the amount of MDA used.

Abstract: The present invention relates to a process for preparing mono-disperse adsorber resin gels by polymerizing monomer droplets to give monodisperse polymers, followed by haloalkylating and crosslinking the resultant polymers, and also relates to the use of these resins.