Abstract: The invention relates to an air exhaust valve (1). The air exhaust valve (1) comprises an inner baffle element (10) located at a radially inside position and an outer baffle element (20) located at a radially outside position and surrounding said inner baffle element (10) for defining an air flow space (70) between said inner baffle element (10) and said outer baffle element (20). There are provided an inner plurality of slits or grooves in said inner baffle element (10) and/or an outer plurality of slits or grooves (21) in said outer baffle element (20).

Abstract: The present invention provides a radiation shielding material, particularly for shielding of particle radiation, comprising a fibre material and a radiation damping filler, wherein the amount of the radiation damping filler is 40 to 95 wt. % based on the dry weight of the radiation shielding material. The present invention further provides a radiation shielding structure, particularly for shielding of particle radiation, comprising a bottom layer and a top layer, wherein a hollow structure is sandwiched between the bottom layer and the top layer, wherein the hollow structure is filled with a radiation damping filler.

Abstract: The invention relates to polyurethanes which comprise biocides, a process for their preparation and the use thereof for the production of maritime articles which have anti-fouling activity.

Abstract: The invention relates to a process for preparing prepolymers containing isocyanate groups by reacting a) diisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups in the presence of c) catalysts, and subsequently separating off the excess monomeric diisocyanates, wherein the diisocyanates a) used are unsymmetrical diisocyanates and the catalysts c) used are organometallic catalysts and these organometallic catalysts are removed, blocked or deactivated before the monomeric diisocyanates are separated off.