Abstract: The invention, relates to a method for producing standard gases (CO and H2) for determining the isotope relationships of oxygen and/or hydrogen, in particular during on-line operation, with a sample being decomposed in a (hot) reactor (11) to produce CO and/or H2, and these components being fed to a mass spectrometer (15), and with the mass spectrometer also the gases obtained from the sample. The invention also relates to an apparatus for providing standard gases. The method according to the invention provides for the standard gases in the reactor (11) to be formed by decomposition, and for initial products which are suitable for this purpose to be fed to the reactor.

Abstract: The invention relates to a novel method for measuring ionic currents when determining isotope ratios and suing a mass spectrometer. Two or more ionic currents are measured in parallel, that is to say caught by catchers and evaluated via respectively assigned electronic measuring system. The assignments between catchers and electronic measuring systems are changed as time progresses.

Abstract: A Faraday collector for measuring ion currents in mass spectrometers, having a cup (11) for capturing the ions, an entrance slit (14) and a secondary electron diaphragm (13) is configured in a special way. The cup (11) consists of two half-shells (18, 19) of solid graphite and his held in a frame (12) with insulators (30).

Abstract: In mass spectrometers with a plasma ion source (ICP-MS), a high ion current takes effect on the entrance of the ion optical system. The components provided there, especially lenses and apertures, have hitherto been made of steel. Atoms and ions are released from the surface of the components by a sputtering effect. This results in a correspondingly spoiling background signal and in losses in the quality of the analysis. To avoid the described effects, the components which are subjected to ion bombardment are made of graphite. The sputter rate and the ion yield of the carbon are much lower than those of steel (iron, nickel and chromium).

Abstract: A slit is disposed as diaphragm in the beam path of a mass spectrometer. The slit width is to be variable in the simplest possible manner. Manual, electric motor-driven, thermoelectric or piezoelectric adjustment devices are known. According to the invention a pneumatic adjustment is provided. A Bourdon tube (12) moves a lever (14), at one end (18) of which slits (19, 20, 21) of differing slit widths are disposed. The lever movements are limited by abutments (22, 23).

Abstract: The invention relates to an appliance for the oxidation of components in organic samples, in particular for the oxidation of components emerging from a gas chromatograph and for preparation for an analysis of isotope ratios by mass spectrometry, having a chamber with a gas inlet and a gas outlet, having an oxidizer inside the chamber and, in particular, having a heating appliance for the chamber. It is known to use copper oxide as oxidizer. The latter requires continual reoxidation to achieve sufficiently good results of measurement. In addition, at high temperatures, coagulation of the copper occurs. An oxidizer composed of nickel oxide is provided according to the present invention. This is extremely stable to temperature. The chamber receiving the oxidizer is advantageously lined with Al.sub.2 O.sub.3.

Abstract: The invention relates to a method and a mass spectrometer for mass spectroscopic or mass spectrometric investigation of particles. The particles are separated in a separating system in accordance with their different masses. In order to reduce detection errors due to scattered particles, there is arranged upstream of a detecting device a correction device which builds up a braking potential in order to suppress particles having an energy loss due to scattering. The invention provides a further, preferably combined correction, by means of which the particles are selected as a function of their direction of motion. For this purpose, the mass spectrometer according to the invention preferably has at least one braking electrode and one quadrupole lens.

Abstract: The invention relates to a process for the laser desorption of analyte molecular ions, especially of biomolecules, from a specimen. The object of the invention is to improve a process of this type in such a way that intact desorption of biomolecules, preferably of large molecular mass, is also possible with a laser. This is achieved by using laser light of a wavelength of about 300 nm or greater than 300 nm and using a matrix which is able to absorb in the selected wavelength range.

Abstract: In isotope mass spectrometry, there is the problem that in the case of very great frequency differences, the less frequent masses are swamped by the more frequent masses in the measurement result or that the corresponding measurement result is falsified. A correction device is proposed, which comprises a quadrupole mass filter with a voltage supply device which is controlled by the ion separation system and is designed in such a manner that the supply voltages of the quadrupole mass filter and thus its characteristic with respect to the mass quantity to be allowed through are switched over synchronously with the varying mass deflection setting of the ion separation system.

Abstract: A method is described for operating a mass spectrometer with a location-resolving detector. In this case, when an ion impinges on the detector, the instantaneous parameters of the analyzer are read and compared with a calibration table, and the instantaneous mass value (to be expected) is determined therefrom in the center of the detector. The location signal of the detector indicates the impingement location of the recorded event and is converted, via a second calibration table, into the deviation of the actual mass from the mean mass. The exact (actual) mass value is calculated from both values. This value is recorded in a memory of a computer.

Abstract: A lens arrangement (30) for the focusing of a beam of electrically charged particles (24) in the beam path of imaging systems, more particularly in mass spectrometers (10), is indicated, the lens arrangement (30) being connected to an electrical voltage supply. The lens arrangement (30) is situated at the location or in the vicinity of the intermediate image (29) produced by the imaging system, and consists of a plurality of plates (32 to 35) disposed in succession, with aligned transmission apertures (38 to 41), the plates being connected to adjustable electrical voltages.

Abstract: Slit means in spectrometers for the analysis of organic and inorganic substances, in particular in mass spectrometers, have hitherto been controlled for varying the slit widths by connecting them in a suitable manner to a metallic wire, through which an electric current flowed, under the influence of which the wire heats up and changes its length. The slit or diaphragm means connected to the wire were then displaced relative to the beam path. It is a great disadvantage that the diaphragms follow a change of the current for controlling the slit widths with a relatively long time delay, which is unacceptable for various types of measuring operation, in particular types of measuring operation under data system control. To eliminate this disadvantage, a device (11) is proposed which has at least one movable slit jaw (12) which is movable to and fro, substantially perpendicular to the beam path (16) and without delay, by a piezo-electric element (14).

Abstract: In a hybrid mass spectrometer, a high-energy collision chamber (8) is arranged in a field-free region (12) which, in the direction of travel of the ions, is located after the first stage (1 to 6). A lens arrangement (9) serves for decelerating daughter ions of different energies to a fixed energy, and preferably at the same time also for shaping the ion beam. Preferably, the hybrid mass spectrometer is of BEQQ configuration.

Abstract: For calibrating mass spectrometers with a plurality of ion targets (1), especially Faraday targets, to which a separate measuring channel is assigned in each case, an electric current from a highly stable electrical voltage-source (6) is supplied, as a measurement reference-value, to the individual measuring channels, in chronological succession, via a resistor (R.sub.2) having a high degree of constancy. For this purpose, a control device (7) is provided, which actuates switching devices (K.sub.1 -K.sub.n) in such a manner that the correct chronological sequence is maintained. The calibrating measurement-values, obtained with the aid of this highly stable current, are intercorrelated in order to form a correction-value, this correlating operation being performed in a calibrating-correction unit (5). Several calibrating measurements, with different currents, can be carried out for each measuring channel (V.sub.1 -V.sub.

Abstract: Automatically controllable loading apparatus for a mass spectrometer or like equipment comprises a rotatable disc for holding a plurality of sample carriers for successive movement into a transfer position. A push rod transfers successive sample carriers from the transfer position to a loading position. Guide means guide the push rod during its transfer movement. The guide means include a shut-off valve adjacent the loading position. Sealing means define in a fixed position between the valve and the transfer position at least one vacuum chamber adapted to be exhausted for the purpose of equalizing the pressure at opposite sides of said valve.

Abstract: A fraction obtained from a liquid chromatograph column is introduced into a cup-shaped collecting vessel 12 having a centrally apertured funnel-shaped bottom surface 14. A sample holder 13 is removably accommodated in the aperture, and after the evaporation of the fraction solvent the remaining residue 11 collects on or in the holder, which may then be removed and directly introduced into the ionization chamber of a mass spectrometer for further analysis.