Abstract: In a device for determining the influence of physical parameters on the lth of a path, an elastically stretchable optical fiber is guided with minimal pretensioning along the path which is subjected to length changes. The optical fiber is mounted at least sectionally on supports subjected to positional changes with changes in the length of the path. A transit-time measuring device is also provided as part of the measuring device together with the optical fiber. The transit-time measuring device includes a light-pulse repeater forming a closed signal path with the optical fiber. The repeater generates signal pulses circulating in the signal path with the periodicity of the signal circulation time of the signal path. From an electronically measured total travel time through the closed signal path and a total number of which signal pulses the electrical display signal can then be derived to determine the length and change in length of the path being measured.

Abstract: An improved normal or superconductive field coil constructed so that individual coils are both axially and radially stable. The individual coils are provided with a holding cylinder at each end with the conductor ends being fixed to the holding cylinder. In another embodiment an electrically insulating, reinforcing cylinder is fixed to the outer periphery of the coil.

Abstract: Monochromatic excitation light penetrates an indicator in an indicator sp. The indicator space is closed off at the side to be brought into contact with the substance to be analyzed by means of a membrane permeable for the component of the substance whose concentration is to be ascertained. The side of the indicator space facing the light-measuring unit of the device is radiation-transmissive. The indicator is set into motion during the measurement operation. Alternatively, the substance to be analyzed, on the other side of the permeable membrane, is set into convective motion during the measurement operation. As a further alternative, both the indicator and the substance to be analyzed are set into motion in mutually perpendicular directions, which however are both parallel to the permeable membrane.

Abstract: An ion-selective electrode device for measuring oxygen concentrations comprises a noble metal reduction electrode connected to a voltage source; a reference electrode connected to said reduction electrode; an ion-selective carrier or ligand membrane disposed in front of the reduction electrode and containing a cation-selective ligand and being permeable to hydrogen ion; a closure membrane to seal the device against the outside atmosphere, the said closure membrane being permeable to oxygen and impermeable to water, and an electroyte containing the ligand cation of said ligand membrane, the said electrolyte being disposed between the said ligand membrane and said closure membrane.

Abstract: An apparatus for an optical measurement of the concentration of substances ncluding at least one monochromator means, one photometer means and one optometric means. A further reference indicator means is added to the indicator means. This further indicator means changes the measuring light and will not be changed by the concentration of the substance to be measured.

Abstract: A fibre optical arrangement for measuring the intensity of an electric current using the Faraday effect, in which the path of light whose state of polarization is influenced by the magnetic field surrounding the conductor through which current flows is marked by the core of an optical fibre which is coiled round the conductor in a number of turns, the optical fibre used in the arrangement being one which has a circular double refraction .alpha. at least of the order of magnitude of a linear double refraction .beta. determined by the structure of the fibre and its coiled arrangement. The fibre is preferably twisted about its longitudinal axis so that the twist is substantially evenly distributed over the length of the optical fibre.

Abstract: An electrostatic emission lens arrangement for producing a microparticle ge of a surface by means of charged particles emitted from such surface and accelerated to a predetermined final energy level. Such arrangement includes two apertured diaphragms arranged in spaced relationship to each other and to the emitting surface, and a voltage biasing source for producing a potential difference between the surface and the adjacent first apertured diaphragm electrode, and a potential difference between the first apertured diaphragm electrode and the second apertured diaphragm electrode.

Abstract: In a so-called Coulter-device with a first and a second chamber, a separag wall between them and a measuring aperture in the separating wall, through which particle-free electrolyte flows from the first chamber into the second chamber, and with first and second electrodes in the first and second chamber resp., at which a measuring impulse indicating a certain property (e.g. volume) is derived upon the passage of a particle, which is supplied to it through a supply capillary ending in front of the measuring aperture, the improvement consisting in means to supply additional particle-free electrolyte to the particle stream at and/or in the neighborhood of the downstream end of the measuring aperture to deflect those particles, which, after passage through the measuring aperture, travel backward to the same and cause error impulses.

Abstract: An arrangement wherein atoms are ionized by contact with a heated ionizing surface and the ions are accelerated along an acceleration path towards an acceleration electrode, and wherein, in order to achieve high current densities, the heated surface is convexly curved towards the acceleration electrode and has a radius of curvature which is substantially smaller than the length of the acceleration path.

Abstract: A housing contains a light source, a monochromator, a photosensitive unit and an oscilloscope-type display. A flexible bundle of fiber-optic elements extends from within the housing out, and is provided at its outer end with a spacing ring. The spacing ring is placed against a skin surface, holding the ends of the fiber-optical bundle properly spaced and oriented relative to the skin surface. At the other end of the bundle, the bundle is subdivided into one branch which receives light from the source, and another branch which emits light refleced from the skin surface into the monochromator. The monochromator projects the spectrum of the skin-reflected light onto the photosensitive unit. The output signal of the photosensitive unit, in a sequential and periodic manner, contains information concerning successive spectral components of the skin-reflected light. The sweep of the display is synchronized with this periodic sequence, so as to display a spectral analysis of the skin-reflected light.

Abstract: Crystalline lithium nitride, stable in air, characterized by a sodium content of less than 5.times.10.sup.-2 weight-percent, a potassium content of less than 10.sup.-2 weight-percent, a magnesium content of less than 1.times.10.sup.-2 weight-percent, and a silicon and iron content of 10.sup.-2 to 10.sup.-3 weight-percent each; is obtained by heating lithium having a purity of at least 99.9% in a vessel made of tungsten, niobium, ruthenium or tantalum in a nitrogen atmosphere at a pressure of at least 250 mm Hg in the absence of oxygen and water at a temperature of from 300.degree. C. to the melting point of lithium nitride.

Abstract: The heat collector system comprises a heat collector connected to a heat p. The heat collector has an inlet conduit and contains a heat transmitting fluid and is effective to take radiation heat from the environment. The heat collector has a structural configuration effective to additionally absorb convection heat as a convector which causes a good heat transmission between the ambient air and the heat transmitting fluid. A rated and controlled cooling device is connected to the heat conduit of the heat collector. The cooling device is effective to supply fluid to the heat collector at a temperature below the temperature of the ambient air. Further features of the invention include a regulating device effective to regulate the difference in temperature between the temperature of the ambient air and the cooling temperature.

Abstract: A method of photochemical separation of isotopes, wherein molecules containing differing isotopes to be separated are selectively excited by laser radiation, and the excited molecules are collectively reacted with a scavenger which is relatively inert to molecules of lesser excitation, the reaction producing a stable addition product which is readily isolatable.

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: A probe having a measuring device for polarographic, potentiometric, ther and like measurements has a high-resistance transducer which is provided with leads. A body of insulating material is arranged about the transducer and a metal-containing body is arranged about the insulating material. The metal-containing body includes a metal layer which is essentially free of pores and essentially impervious to the diffusion of liquid therethrough and which thus seals the insulating material against contamination by foreign matter. A metal layer which is essentially free of pores and essentially impervious to the diffusion of liquid therethrough may be formed by sputtering the metal onto a substrate using a high-frequency field at an output of 10 to 40 watts per square centimeter of target surface, the sputtering operation being carried out for a period of 5 to 10 minutes in an Ar atmosphere having a pressure of 8 .times.10.sup.-4 torr.

Abstract: Monochromatic excitation light is passed into an indicator chamber to exc the indicator therein. The side of the indicator chamber in contact with the substance to be analyzed is closed off by a membrane which is permeable to the component of that substance whose concentration is to be determined. The side through which the radiation emitted from the indicator towards the light-measuring unit of the apparatus passes is transmissive for the emitted radiation. The direction of introduction of monochromatic excitation radiation, and the direction in which the radiation emitted from the indicator towards the light-measuring unit, include an angle relative to each other, and are preferably perpendicular.

Abstract: The increase in concentration of one or several plasma-proteins in the blood is specific for various pathological processes, especially inflammations. A medicament which in a typical way, exactly contains increasingly available plasma-proteins for a pathological process, attenuates the progress of the pathological process, as by this means, the defence system of the body itself is strengthened, which reacts in a specific way on such pathological processes, with the increased formation of one or several plasma-proteins specific for this. This effect is especially demonstrated in regard to Fibrinogen. It demonstrates further that the effect of the Fibrinogen is thereupon to be traced back in that, in regard to reaction with Thrombin at the point of the inflammation, the fibrinopeptides A and B are formed.

Abstract: A corpuscular beam microscope for ring segment focusing is provided with a ondenser and an objective magnetic lens system which is disposed substantially axially symmetrically about the microscope axis for the purpose of generating two field maxima separated by a distance not exceeding five times the arithmetic means of half the half height widths of the component magnetic fields forming the maxima. The provision of such a magnetic lens system facilitates the elimination of aperture aberrations of the first and second order and the elimination of chromatic aberrations of zero order and partly of the first order as well as certain extra-axial defects.

Abstract: A display process for the optical presentation of information which process omprises impinging laser beams modulated as to their direction, intensity and/or frequency, upon a transparent target containing a fluorescent substance which is excited by said laser beams to optical fluorescence, e.g., which absorbs in the ultraviolet range and yields fluorescent radiation in the visible range; typical ions capable of fluorescence are uranyl ions or ions of the rare earth elements.

Abstract: A transmission-type charged particle beam apparatus comprising a vacuum elope enclosing, first means, having at least ten individual charged particle sources to separately produce at least ten individual charged particle beams, second means to supporting a specimen to be investigated; third means to project each of the beams along a different beam path through a predetermined region of the specimen, the beam paths collectively converging about a rotational axis of symmetry at equal angles of at least 30.degree.