Abstract: A chamber, for bounding a plasma generation area in a vacuum pressure sensor, includes an electrically conductive casing element located radially on an outside relative to a central axis. The chamber includes electrically conductive wall elements arranged substantially perpendicular to the central axis and connected to the electrically conductive casing element. At least one of the wall elements has a first opening, through which the central axis extends. The electrically conductive casing element comprises at least a first and a second region. The first region is located closer to the central axis than the second region. The electrically conductive casing element is conical at least in part.

Abstract: Chamber (11, 12, 13) for bounding a plasma generation area (42) in a vacuum pressure sensor (40), wherein the chamber comprises an electrically conductive casing element (1, 1?, 1?) located radially on the outside relative to a central axis, wherein the chamber comprises electrically conductive wall elements (2, 2?, 2?) arranged substantially perpendicular to the central axis and connected to the casing element, wherein at least one of the wall elements has a first opening (3), through which the central axis extends, wherein the casing element comprises at least a first (B1) and a second region (B2), wherein the first region is located closer to the central axis than the second region. The invention further relates to a vacuum pressure sensor comprising the chamber.

Abstract: Chamber (11, 12, 13) for bounding a plasma generation area (42) in a vacuum pressure sensor (40), wherein the chamber comprises an electrically conductive casing element (1, 1?, 1?) located radially on the outside relative to a central axis, wherein the chamber comprises electrically conductive wall elements (2, 2?, 2?) arranged substantially perpendicular to the central axis and connected to the casing element, wherein at least one of the wall elements has a first opening (3), through which the central axis extends, wherein the casing element comprises at least a first (B1) and a second region (B2), wherein the first region is located closer to the central axis than the second region. The invention further relates to a vacuum pressure sensor comprising the chamber.

Abstract: The catalyst comprising at least one alkali metal on a spinel or inverse spinel as carrier may be doped with at least one compound of an alkali metal and/or alkaline earth metal, where the alkali metal/carrier ratio by weight is from 0.01 to 5 and, when a dopant is present, the dopant/carrier ratio by weight is from 0.01 to 5.The spinel therein has formula (I) and the inverse spinel has formula (II)AB.sub.2 X.sub.4 (I)B(AB)X.sub.4 (II)whereA is divalent metal,B is tri- or tetravalent metal,X is O, S, Se, halogen, pseudohalogen,the charges being balanced, and A preferably being selected from Mg, Cr, Fe, Zn, Mn, Co, Ni, Cu, Cd, Sn and mixtures thereof, and B being selected from Al, Ga, In, Fe, V, Cr, Ti, Pb, Mn, Co, Rh, Ni, Si and mixtures thereof, and X being O.

Abstract: The catalyst comprises at least one alkali metal on a doped carrier, where the doped carrier can be prepared from at least one zirconium and/or alkaline earth metal compound as carrier and at least one alkali metal compound as dopant and calcining the doped carrier at 350.degree. C. or below, the alkali metal/carrier ratio by weight being from 0.01 to 5 and the dopant/carrier ratio by weight being from 0.01 to 5.