Abstract: Ethane and higher hydrocarbons are separated by rectification from natural gas under elevated pressure. To obtain higher ethane yields, even for gases poor in ethane, an open mixture cycle with multistage fractional condensation is employed for the production of cold. One part of the thus-obtained condensates are introduced into the rectifying column to obtain the C.sub.2+ hydrocarbons and the other part is recirculated to provide the required cold.

Abstract: The dimensions and light output of a beam in a shadow mask cathode-ray tube are determined by means of an optical system 7 focussed on a phosphor dot to pick up and record the light generated by a ray 4 passing through a single aperture 6 in the shadow mask 2. The cathode-ray beam 1 is moved so that the whole cross-section of the beam passes the aperture 4. The detected light outputs are plotted to provide an accurate representation of the whole beam.

Abstract: Convergence of the beams of an in-line gun shadow mask cathode-ray tube is provided by windings on a common core and generating pairs of quadruple and six-pole magnetic fields, respectively. The core is provided with non-magnetic ribs each having a projection for the purpose of locating the windings.

Abstract: In the separation in a rectification column of methane and optionally lower-boiling components from a methane-containing crude gas, which gas contains additionally higher-boiling hydrocarbons, hydrogen sulfide, carbon dioxide, or mixtures thereof, wherein an auxiliary cycle containing a fluid medium is employed for the production of cooling to produce reflux liquid at the head of the rectifying column, an improvement is provided wherein liquid in the rectifying column positioned above the column sump and below the column head, is vaporized in indirect heat exchange with condensing cycle medium.

Abstract: The device structure is a bi-polar transistor having a region of inert atoms located in the collector adjacent to the base-collector junction. Another embodiment of the invention is a complementary insulated gate field effect transistor (IGFET) structure having N and P channel IGFETs with regions of implanted ions beneath the source and drain of one or both transistors, and/or annular regions projecting inwardly from the surface that surround or separate the different types of IGFETs.