Abstract: A tandem-type pneumatic brake booster, in particular for hydraulic vehicle brake systems, having a housing comprising a first and a second housing half shell, the interior of which is divided with the aid of a partition into a front and a rear booster chamber, wherein the partition has a centrally arranged, circular cavity, through which a control housing or a cylindrical control housing extension extends, and the partition rests sealingly against the control housing or the control housing extension by a sealing element, having a first and a second movable wall, which respectively subdivide the front and the rear booster chamber into a first low-pressure chamber and a first working chamber and into a second low-pressure chamber and a second working chamber, having at least one connecting conduit between the first working chamber and the second working chamber in order to equalize the pressure between said two working chambers.

Abstract: A tandem-type pneumatic brake booster, in particular for hydraulic vehicle brake systems, having a housing comprising a first and a second housing half shell, the interior of which is divided with the aid of a partition into a front and a rear booster chamber, wherein the partition has a centrally arranged, circular cavity, through which a control housing or a cylindrical control housing extension extends, and the partition rests sealingly against the control housing or the control housing extension by a sealing element, having a first and a second movable wall, which respectively subdivide the front and the rear booster chamber into a first low-pressure chamber and a first working chamber and into a second low-pressure chamber and a second working chamber, having at least one connecting conduit between the first working chamber and the second working chamber in order to equalize the pressure between said two working chambers.

Abstract: A method for the preparation of tetrahydrofurfuryl-(2)-methacrylate by transesterification of methyl methacrylate or ethyl methacrylate with tetrahydrofurfuryl-(2)-methyl alcohol in the presence of the corresponding alkali metal or alkaline earth metal as a catalyst and while air or oxygen is passed through the reaction mixture.