Abstract: The invention relates to a process for the polymerization of vinyl-containing monomers such as, for example, monomeric vinyl halides, in a reaction mixture, in which process less waste is generated.

Abstract: The invention relates to a process for the polymerisation of vinyl-containing monomers such as, for example, monomeric vinyl halides, in a reaction mixture, in which process less waste is generated.

Abstract: In a method for scanning microscopy, for which the surface of a sample is scanned point-by-point using a tunnel tip and locally resolved tunnel current measurement is performed, during scanning the tunnel tip is remagnetized by a predetermined remagnetization frequency, and from the tunnel current (It) or a z coordinate of the distance between the tunnel tip and the sample or a value derived from this, locally resolved signal components are derived, occurring at the remagnetization frequency and being characteristic for magnetic sample properties, whereby on the basis of the derived signal components an imaging of the magnetic structure of the sample surface is performed.

Abstract: The invention relates to the destruction of foams that are produced in various industrial processes, especially in the degassing and/or removal of monomers from plastics dispersions, by the use of porous filter elements without using moving mechanical foam-destroying devices and/or without the addition of chemical foam-destroying agents.

Abstract: An essentially linear ion beam is derived from an ion emitting sample, inding a high-frequency mass filter of essentially linear ion beam path, the ion beam path extending towards an ion-electron converter of general rotation symmetrical shape with respect to an axis, the ion-electron converter having an axis aligned with the essentially linear ion beam path and including an electrode which has an aperture traversed by the beam from the source after having passed through the filter, the electrode having a secondary electron-emissive surface on a side thereof which is averted from the ion source and formed as a smoothly curved concave surface defining a converter chamber, the ions which have passed through the aperture being reflected back unto the secondary electron-emissive surface to then being detected by an electrode positioned within the converter chamber.

Abstract: An electron beam is monochromatized, brought to an appropriate energy lev by acceleration or slowing down, and focussed on a monocrystal electron scattering surface. Backscattered electrons are measured at complementary scattering angles, but only after slow electrons are separated or trapped that result from inelastic interaction with the crystal. The response of the detectors of a pair, in pulse count or current flow, allows the degree of spin polarization P to be calculated byP=f.times.(I.sub.1 -I.sub.2)/I.sub.1 +I.sub.2).

Abstract: This invention relates to a valve for the introduction of a gas into a liquid media comprising a housing, said housing having an exit port at one end, and exit port at the opposite end and a gas entrance port, said housing containing a movable hollow piston in a substantially water-tight connection with said housing, said movable hollow piston being sealed at each end and having gas distribution jets at one end, and a gas entrance port in communication with said housing gas entrance port when said hollow piston is extended, said hollow piston being in a substantially gas-tight connection with said housing when retracted, and means for extending and retracting said movable hollow piston in said housing, whereby when said hollow piston is extended, said gas distribution jets are exposed beyond said housing and a gas path is created from said gas entrance port to and through said gas distribution jets.

Abstract: The ion-electron converter is primarily intended for the measurement of small positive ion currents. The essential feature of the converter is its curved conversion electrode which generates an electrostatic field with favorable ion-optical properties; in addition, it avoids high field strength at the conversion electrode, thus reducing spurious field electron emission. Both properties result in an ion detector of high efficiency and sensitivity for positive ions.

Abstract: A method for controlling the removal, by means of ion etching, of a thin layer or regions of the layer as determined by masks, from a substrate of a sample which has a chemical composition different than that of the layer to be removed. During the ion etching process, an electrical signal which changes after the removal of the thin layer is derived from the substrate or from its mount, or from an electrode disposed in the vicinity of said substrate and this electrical signal is utilized to control an arrangement which influences the ion bombardment of the surface of the sample.