Abstract: An automatic sampling apparatus particularly adapted for flameless atomic absorption spectrometers has a turntable carrying a ring of sample containers. The turntable is rotatably mounted on a base plate which in turn is mounted for limited pivotal movement on a support. A rinse station for a sample probe is provided on the base plate adjacent the periphery of the turntable. A sample probe in the form of an elongated tube angled at one end to form a pipette-like tip is mounted for swinging movement about a transverse axis and concomitant rotation about its longitudinal axis so that, at both limits of movement about the transverse axis, the probe tip is directed generally downwardly.

Abstract: A device for atomizing a sample for so-called flameless atomic absorption spectroscopic measurements of the type in which an electrically conducting hollow tube, into which the sample is introduced as by a central port in the side of the tube, is heated by the passage of current from electrodes contacting the ends of the tube. A protective inert gas is caused to surround the interior and exterior of the tube to exclude air to avoid oxidation of the sample tube which may be graphite. The improvement comprises introducing the protective gas into both ends of the sample tube so that it leaves the interior through the central port from which it may be sucked outside of a surrounding housing. The exterior walls of the sample tube may be provided with protective gas either by means of an auxiliary gas flow or by leading the gas from the bore around the outside of the tube before withdrawing it through the surrounding housing.

Abstract: An automatic sample preparation device for use in flameless atomic absorption spectroscopy or the like, wherein samples to be examined for a particular element are successively mixed with graduated, metered additions of the element to be determined, which includes, in combination, controlled delivery pumping apparatus, a storage vessel system containing dilution agents connected to the inlet side of the pumping apparatus, a dosing probe connected to the outlet side of the pumping apparatus, a stepwise movable carrier, a plurality of sample containers mounted on the carrier, a sample withdrawing device for withdrawing samples from the carrier, and a control unit for moving the dosing probe with respect to the carrier so that one group of at least two successive sample containers on the carrier can be simultaneously mixed with graduated, metered additions of the element to be determined prior to sample withdrawal.

Abstract: Method and apparatus for introducing a sample to be analyzed through an introduction aperture into a graphite tube of a graphite tube cell of an atomic absorption spectrometer, wherein a plurality of sample containers containing the samples to be analyzed are placed in a row in a sample holding device, the sample containers being open at both ends. The sample containers are successively transported to an introduction device and a sample container is inserted into the introduction aperture of the graphite tube by means of the introduction device. The sample is transferred from the sample container into the graphite tube and the sample container is removed therefrom and the next subsequent sample container is transported to the introduction device.

Abstract: A graphite furnace for flameless atomic absorption spectroscopy comprising a graphite sample tube with a sample port at the mid-point of its length. Electrodes supportively contact the tube ends and pass electrical heating current through the tube. The electrodes have hollow cylindrical portions which laterally envelope the tube over substantially its entire length, one of the electrodes being longer than the other and containing a radial bore in registration with the sample port. The cylindrical portions of the electrodes are disposed with complementary-shaped recesses in cooling jackets which encase all but the mid-length regions of the electrode cylindrical portions. The electrodes fit readily in the cooling jackets at room temperature due to differential expansion of these members. The sample tube, electrodes, cooling jackets and associated structure are mounted on a base with provisions for adjustment of the tube about various orthogonal axes.

Abstract: A method of atomization of a sample for analysis by atomic absorption spectroscopy in which the sample is progressively heated to drying, ashing and atomization temperatures by subjecting it sequentially to discrete ambient temperature increments.A preferred form of apparatus for carrying out the method takes the form of a graphite fabric conveyor belt which carries the sample substance and travels transversely through three hollow cylindrical graphite tubes disposed in spaced justaposition with longitudinal axes parallel. The belt passes through each tube in sequence, by way of pairs of aligned longitudinal slots in the sidewalls of the tubes, the slots defining a common chordal plane of the tubes. Each tube is maintained, respectively in the direction of belt travel, at drying, ashing and atomization temperature for the particular sample. The tubes are heated by an electrical current of appropriate magnitude passed between pairs of electrodes associated with the ends of the tubes.