Abstract: A process for controlled manufacturing of olefin trimers and olefin tetramers is disclosed, wherein the olefin monomers are processed into olefin trimers and olefin tetramers by a two-step catalytic process involving separation and recycling of reaction products.

Abstract: The construction is a coaxial cavity resonator (20, 30, 40, 50) comprising at least one conductive body (11, 31), which body is open at one end and shortened from a quarter-wave resonator. The conductive body includes a main rod (16), which is in one end attached to the cavity wall (15), and a main disc (17) attached to the free end of the main rod (16). The cavity (12) further comprises one or more conductive plates (21, 41, 51) located between the main disc (17) and the side walls (13), at the first side (17a) of, and out of galvanic contact with, the main disc (17). The shortening is carried out by creating air-insulated extra capacitance between the resonator cavity walls via the conductive plates and a mechanical structure at the open end of the conductive body.

Abstract: The invention relates to an air-insulated coaxial resonator, which is particularly suitable for a structural part in duplex filters. The resonator has an inner conductor (301) extended at one end, so that it forms extra capacitance with the cover (303) of the resonator and the upper part (302y) of the outer conductor. Because of the extra capacitance, a resonator of a certain frequency is shorter than a corresponding quarter-wave resonator. Because of this it is also mechanically stronger and is more stable in its properties. The extension of the inner conductor and the shortening of the construction also have a dissipation-reducing effect. The extension (304, 305, 306a, 306b) can also be used for tuning the resonator and for coupling to the adjacent circuit elements. In a construction according to the invention, a third harmonic of the basic frequency component does not occur, which is a remarkable advantage in the manufacture of filters.