Abstract: A novel process for the preparation of compounds of the formula ##STR1## with cis or trans structure in racemic or optically active form wherein R is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms and aryl of 6 to 12 carbon atoms comprising reacting an optically active isomer, or racemate of the formula ##STR2## wherein R has the above definition and the way line indicates Z or E geometry with a gem-dimethyl cyclopropanation agent if there is Z geometry to obtain a compound of the formula ##STR3## or if the geometry is E with a gem-dimethyl cyclopropanation agent other than isopropylidene triphenyl phosphorane to obtain a compound of the formula ##STR4## wherein R has the above definition and the cyclopropane ring has the trans configuration and either hydrolyzing the compound of formula III or IIIa to obtain a compound of the formula ##STR5## and then cleaving the 4,5 bond to obtain the corresponding compound of formula I or simultaneously cleaving the 4,5 bond and hydrolyzing t

Abstract: An enantioselective process for the preparation of hemicaronic aldehyde with a cis or trans structure and novel intermediates.

Abstract: Apparatus for steam sealing a shaft of a steam turbine is disclosed. The apparatus preferably includes at least four sealing rings which encircle the shaft of the steam turbine. The sealing rings are spaced apart to define at least three regions. A first region, closest to the blades of the turbine, receives contaminated steam and exhibits a below-atmospheric pressure. A third region, furthest from the blades of the turbine, also exhibits a pressure which is less than atmospheric pressure, but which pressure is also less than the pressure in the first region. A second region, arranged between said first and third regions, receives uncontaminated steam and exhibits a pressure which is greater than atmospheric pressure.

Abstract: A method and device for testing tube leakage, more particularly in a moisture-separator reheat superheater, to determine a tightness of separating walls between two flowing media which are separated from each other is disclosed. A test medium, e.g. an inert gas, such as helium, is introduced into a first medium whereby a lack of tightness in the separating walls can be quantitatively measured by a mass spectrometer in a sample taken from the second medium. In the event that the second medium consists of a number of phases, the nongaseous phases can be separated out by first condensing and, if necessary, by freezing the sample prior to testing. The test gas may furthermore be supplied to the second medium through a calibrated orifice to permit a determination of the extent of the tube leakage.