Abstract: The invention relates to a gastight connection between tubes of small diameter of metals or metal alloys having different melting points, more particularly copper and aluminium, wherein the end zone of the first tube (1) is opened out and the second tube (2) of a lower-melting material is inserted and soldered into the opened-out portion (3), the internal generated surface of the opened-out portion (3) merging via an internal cone (4) and extension (38) into that zone of the first tube (1) which is not opened out, a sleeve (34) of special steel possibly being inserted in the end zone of the second tube (2).

Abstract: The characterizing features of the invention are that a guide tube is provided which is disposed at least partially outside the evaporator plate and partially in the suction tube, is directly or indirectly retained on the evaporator and has a somewhat larger internal diameter than the external diameter of the throttle/capillary tube and a substantially smaller external diameter than that of the internal diameter of the suction tube; the throttle/capillary tube is inserted in the guide tube from outside and the compressor side end zone of the internal generated surface of the guide tube is connected pressure-tight inside a first longitudinal portion of the coolant supply line disposed in the guide tube to the associated zone of the external generated surface of the throttle/capillary tube and terminates in the guide tube; and the guide tube forms a second longitudinal portion of the coolant supply line having a cross-section widened in comparison with the capillary flow cross-section, and the inside space of t

Abstract: N-(.alpha.-alkoxyethyl)-carboxylic acid amides of the ##EQU1## where R.sup.1 is H or lower alkyl and R.sup.2 is lower alkyl, are prepared by anodic alkoxylation of a N-acyl-.alpha.-aminopropionic acid neutralized at a rate of from 3 to 50 mole % with an alcohol R.sup.2 OH. The compounds are valuable intermediate products for the preparation of N-vinylcarboxylic acid amides which may be converted to water-soluble polymers having multiple technological properties.