Abstract: The invention relates to a new method for the separation of gaseous paramagnetic species from diamagnetic or weakly paramagnetic gaseous species by contacting the mixture of such species with a high Tc superconductive material in permeable form, so that one of the species is enriched respective of the other one by permeation through such porous barrier.

Abstract: Continuous malleable superconductive material which can be machined, rolled and soldered, being the product of sintering at an elevated temperature and pressure of a metal plated powder of a compound QBa.sub.2 Cu.sub.3 O.sub.7-x wherein Q is yttrium or europium, where x is smaller than one. The metal is advantageously silver and the plating process is one without the use of electricity. A preferred range of silver content is about 5 to 32 weight per cent, and the silver forms an essentially continuous phase in the superconductive material. Sintering can be done at from about 350.degree. and 950.degree. C., with a preferred range of 400.degree. to 900.degree. C. The superconductive material of the invention exhibits transition to zero-resisitivity state and the Meissner effect.

Abstract: There is provided a scaife for the polishing of gemstones wherein the abrasive material is embedded in a matrix of a material maintained in the solid state, which material has a high enthalpy of phase transition from solid to liquid. Suitable materials are frozen water, frozen water/organic liquid mixtures such as water/alkanol mixtures and suitable metals or metal alloys. There is also provided a process for the polishing of gemstones which comprises a process for the polishing of gemstones which comprises establishing a layer of abrasive embedded in a suitable solid matrix in or on the surface of a rotatory plate and polishing said gemstones, overheating being prevented by the high enthalpy of solid/liquid transition of the said matrix.

Abstract: Process for modifying in situ the electrical and/or optical properties of an electrochemically-deposited interlayer within a polyimide film, the interlayer being comprised of particulate silver and/or gold, by heating the interlayer, either in its entirety or in a spatially selective manner, so as to sinter the particulate silver and/or gold without adversely affecting the properties of the polyimide, and the film structure produced thereby.

Abstract: There is provided a scaife for the polishing of gemstones wherein the abrasive material is embedded in a matrix of a material maintained in the solid state, which material has a high enthalpy of phase transition from solid to liquid. Suitable materials are frozen water, frozen water/organic liquid mixtures such as water/alkanol mixtures and suitable metals or metal alloys. There is also provided a process for the polishing of gemstones which comprises establishing a layer of abrasive embedded in a suitable solid matrix in or on the surface of a rotatory plate and polishing the gemstones, overheating being prevented by the high enthalpy of solid/liquid transition of the said matrix.

Abstract: The invention relates to a process for the production of a contact lens, which comprises coating a tool made of an inert material, having a curvature corresponding to that of one of the optical surfaces of the lens to be produced, with a layer of solid polymer, and machining the outer surface of said polymer to the desired curvature of the second surface of said lens while supported by said tool, and to a tool for carrying out such process.

Abstract: A photosensitive recording medium for recording spatially modulated optical data and for the recording of holographic information in real time, comprising a polymeric sheet containing a photosensitizer adapted to bring about a change of the refractive index of the polymer upon irradiation in the visible or in the UV range. A process for recording spatially modulated data and for the recording of holographic information in real time, which comprises preparing a recording medium as defined above and recording the information by means of a holographic set-up.

Abstract: A method for recording spatially modulated optical data and for the recording of holographic information in real time, comprising preparing a photosensitive recording medium comprising a polymeric sheet containing a photosensitizer adapted to bring about a change of the refractive index of the polymer upon irradiation in the visible or in the UV range and recording the information by means of a holographic set-up.