Abstract: For nebulizing sample liquid for spectroscopical purposes a liquid to be nebulized is pressurized to a minimum pressure of 30 bar through a high-pressure pump formed as a separate unit, and is nebulized through a nozzle having a smallest flow aperture of less than 5.multidot.10.sup.-9 m.sup.2. The high-pressure pump and the nozzle are interconnected through conduits. In one embodiment the pump takes in pure solvent. The sample is taken in on the high-pressure side through a loop, which is arranged to be connected between pump and nozzle.

Abstract: An atomic absorption spectrophotometer for simultaneously measuring a plurality of elements different in kind from each other. A cylindrical heating furnace is provided for heating a sample being analyzed to dry, ash and atomize the sample thereby producing atomic vapor. A plurality of hollow-cathode discharge tubes corresponding in number to the elements being detected are arranged for simultaneously emitting light beams respectively containing line spectra of the respective elements, to cause the light beams to be incident upon the heating furnace at respective angles of inclination with respect to a central axis of the heating furnace. A plurality of spectral detection systems are arranged behind the heating furnace in relation to the angles of inclination, for respectively spectral-diffracting and receiving the light beams having their respective line spectra absorbed by the atomic vapor.

Abstract: In an atomic absorption spectrophotometer including an electric furnace for drying and ashing a liquid sample to be analyzed and then atomizing the sample to generate atomic vapor, a low-pressure lamp for emitting light having a spectrum of an element to be analyzed onto the atomic vapor atomized in the electric furnace, a monochromator for splitting the transmitted light from the electric furnace and selecting a wavelength of an atomic absorption line absorbed by the element to be analyzed, and a signal processing unit for performing signal processing on the light having the selected wavelength supplied from the monochromator, the electric furnace is an airtight mechanism for maintaining airtightness of the inside of the electric furnace and an evacuation unit for evacuating the inside of the electric furnace to a pressure equal to the pressure inside the lamp.

Abstract: Electrical contact members 20, 22 for supplying transverse electrical current to a tubular furnace member (22) for electrothermal atomization of samples for analysis by atomic absorption spectrophotometry, the tubular furnace member having diametrically opposite, longitudinally-extending contact ribs (84, 86). The contact members (20, 22) form, in operative assembly, a cavity 88 in which tubular furnace member (24) is accommodated and is held between V-shaped channels (44, 76) in contact members (20, 22). Cavity 88 is formed by a recess (36) in one contact member (20) and covered, except for a separating gap, by the other contact member (22). Respective inert protective gas passages (62, 82) terminate at one end in channels 44, 76.

Abstract: In an apparatus for electrothermal atomization, which can be used for flameless atomic absorption spectroscopy as well as for flameless atomic emission spectroscopy, a platform positioned in a graphite tube is divided into two functional axially adjacent. One of the regions serves as the holding part and the other serves as the sample-carrying part. The holding part is mounted in the area of one of the tube ends and the sample-carrying part protrudes unsupported into the interior of the tube.

Abstract: A method of atomic spectroscopy is provided involving the steps of inserting a probe into a cuvette, depositing a sample to be atomized onto the probe by means of a sample dispenser, withdrawing the probe from the cuvette, heating the cuvette to a desired temperature sufficient to atomize the sample, and then reinserting the probe into the cuvette. The sample dispenser may be a manually-operated pipette, or the dosing tube of an autosampler. Liquid samples may be dried by heating the cuvette to a temperature lower than the atomization temperature before withdrawing the probe from the cuvette. Both solid and liquid samples may be atomized by this procedure. Such samples also may be ashed where appropriate by heating the cuvette to a second temperature between the first temperature and the atomization temperature before withdrawing the probe from the cuvette. A spectrophotometer using the technique is also described.

Abstract: A process which extends the measurement range of Zeeman atomic absorption spectroscopy by linearization of the calibration curve in the region of relatively high sample concentration. The intensities of the Zeeman components I.pi.o, I.sigma.o, I.pi. and I.sigma.

Abstract: A method and apparatus are provided for mapping the surface morphology of an object in order to detect and repair structural defects in the object or to distinguish surface features. A beam of light having a single frequency, such as a laser, is scanned across a plurality of locations on the object's surface and the light reflected from each surface location is received and analyzed by a spectrometer and a multi-channel analyzer. The refelected light originating from the laser beam which is absorbed by the surface is shifted in frequency by an amount determined by the type and concentration of molecular bonding of the surface material. The type and concentration of bonding for each scanning location is represented by a set of binary data which are then used to generate a composite visual display of the surface in which each pixel has a color and intensity determined by the set of binary data which represent the type and concentration of bonding.

Abstract: A matrix modifier of finely-divided metallic palladium dispersed to contact a metal constituent to improve analysis of the constituent during graphite furnace atomic absorption spectroscopy. The palladium interacts with a variety of metals in a sample to increase the vaporization temperatures of the metals. One way of contacting palladium with the metal analyte is to introduce it as a salt in solution with the sample into the graphite furnace along with a surfactant. A finely-divided metallic palladium having high surface area is produced in the furnace by introduction of hydrogen gas, which acts as a reducing agent, to reduce and maintain palladium in its metallic form at an early point in the temperature program, prior to evaporation of the surfactant.

Abstract: An electrothermal atomizer comprises a tubular graphite body (1) whose ends are clamped between two pairs of graphite contact members (2,4;3,5) which are arranged to form a containment zone for the tubular body (1). The graphite contact members (2,4;3,5) clamp the ends of the tubular body (1) in a radial direction and are separable from each other by an upwardly pivotting movement of the members (2,3). The lower contact members (4,5) are urged towards each other in the direction of the longitudinal axis of the tubular body (1) by means of a leaf spring (42) so that when the clamping force on the tubular body (1) is released by raising the upper contact members (2,3) the tubular body (1) is lightly retained by the lower contact members (4,5). Thus easy access for adjusting the orientation of the tubular body (1) can be obtained, for example to adjust the orientation of the dosing aperture and/or probe entry slot (8).

Abstract: An absorption profile indicative of a relation in atomic absorption spectroscopy between the absorbance of a desired element and time has a constant half-width independent of the concentration of the desired element in a sample, and hence the half-width of absorption profile with respect to the desired element can be previously determined from data which is obtained by the measurement of a standard sample. In an atomic absorption spectrophotometer herein disclosed, the half-width of absorption profile is previously determined in the above-mentioned manner, and the true peak value of an absorption profile obtained by measuring a sample which contains the desired element at a high concentration, is calculated using the time width of this absorption profile at a predetermined absorbance and the previously-determined half-width.

Abstract: Unitary receptacle and contact pieces for vaporization and spectroscopic analysis of an analysis sample. Receptacle means are incorporated in the receptacle reception of the sample. The contact pieces are formed integrally with the receptacle for connection of the reception means to an electrical supply unit to enable the sample to be heated. The reception means may constitute a bore in the receptacle, a cup for containing an analysis sample engageable in the bore and additional contact pieces formed integrally with the cup for connection of the cup with a current supply unit therefor.

Abstract: A graphite probe for an electrothermal atomizer comprises a thick stem portion (3) carrying a thin head portion (2) which meets the stem portion (3) at a step (4) which, in operation, is located outside a cuvette (6) adjacent to a slot (7) through which the probe head (2) is inserted into the cuvette (6). A sample deposition aperture (8) is provided in the cuvette (6) through which a sample can be deposited via a dosing tube (9) on a part (10) of the head portion (2) of the probe. The part (10) of the head portion (2) is separated from the rest of the probe by a ridge (5) which extends across the width of the head (2). The ridge (5) prevents liquid samples having a low surface tension from spreading towards the step (4) and has a mass such that its temperature increase matches that of the rest of the head portion (2) thus reducing the production of double peaks in the measured absorption.

Abstract: A tube cell for flameless atomic absorption spectrophotometry has a transverse cross-section with the portion above a longitudinally extending line midway between the top and bottom of the tube cell having a smaller cross-sectional area than the portion below that line. The tube cell has an elongated aperture formed close to the bottom of the tube cell for inserting a probe or platform carrying a sample to be analyzed. The cross-section of the tube cell is shaped to maximize the size of the probe which can be used, and accordingly, the sample volume, while keeping the total cross-sectional area to a minimum in order to maximize chemical sensitivity. A number of different cross-sectional shapes are described including a triangular cross-section.

Abstract: The present invention is directed to a lamp assembly for use in atomic absorption spectrometers in which an atomic element hollow cathode lamp assembly has a lamp formed by a hollow cathode electrode and an anode electrode within a sealed envelope. A base structure is attached to the envelope, and located within the base structure is a resistor network consisting of four resistors connected to a common lead and having four plug terminals protruding from the base structure. Two further plug terminals also protruding from the base structure are connected respectively to the cathode and anode electrodes to provide a connecting structure for connecting these electrodes to a lamp power supply. The five plug terminals protruding from the base structure and connected respectively to the resistors and the common lead provide a further connecting structure of the resistor network to a measurement circuit in an atomic absorption spectrophotometer.

Abstract: The invention relates to a method and device for electrothermal atomization of a sample material, particularly for use in atomic absorption or atomic fluorescence spectroscopy in which an atomizing apparatus including a graphite tube sealed towards ambience is connected to a pressure gas source. The gas inlets provided in said atomizing apparatus serve to produce a symmetrical configuration of an atomized sample material cloud, the atomization of the sample material is acheived by a respective temperature increase which is combined with a pressure gas increase at least during a period of temperature increase. The relation between the starting pressure of the gas and the final pressure of the gas is substantially equal to the relation between the starting temperature and the final temperature. The device used for carrying out the method of the invention includes a control system for control of the temperature and the pressure in said atomization apparatus.

Abstract: An electrothermal atomizer comprises a cuvette (1) clamped between two electrodes (2,3) to which an electrical power supply (4) is connected. A probe comprising a tubular head portion (5) and a stem portion (6) is insertable in and removable from the cuvette (1) by means of a rack (9) driven by a motor via a gear (10).By making the probe head (5) in the form of a tube, a large sample volume can be accommodated, and by forming the stem (6) at the top of the tube (5), spreading of acid samples along the stem during the drying phase is minimized.

Abstract: In a heating device for atomic absorption spectrometers with electrothermal excitation of a sample, a tubular body for receiving the sample comprises a radial aperture (15) for introducing the sample at the central part of the tubular body. A pair of contacts (1, 2) can be cooled comprise current supplies (3), each consisting of a detachable upper part (5) and a fixed lower part (6) with the upper part and the lower part being connected together so as to be detachable. Each contact comprises an aperture (9) which is coaxial with the tubular body with the apertures extending partly in the upper part and partly in the lower part of the contacts and holding the ends of the tubular body. Damage and deformations of the contacts are avoided in that the diameters of the apertures (9), with the upper parts (5) laid flush on the lower parts (6), are shorter in the vertical direction than in the horizontal direction.

Abstract: An electrothermal atomizer comprises a graphite tubular member (1) which is clamped between two pairs of graphite contact members (3,5). The contact members are provided with semicircular grooves (14,22) between which the tubular member is clamped with a sufficient force to flex the wall of the tubular member to conform to the profile of the grooves. This arrangement improves the electrical contact between the tubular member (1) and the contact members (3,5) as contact over an area is provided rather than point or line contact.

Abstract: An improved source lamp assembly for use in atomic absorption spectrophotometers is described having encoded structures for identifying the atomic element of the source lamp assembly, as well as to represent lamp operating current. The encoding structures are formed by way of mechanical, optical, or magnetic means. In particular, a mechanical arrangement involves a plurality of projections and recesses, either formed relative to a base structure of the lamp assembly or relative to an attached card-like structure. A card reading device is used to read this card-like structure. These alternative arrangements can be also used relative to optical encoding or magnetic encoding.

Abstract: A double polarized light beam spectrophotometer of a light-source modulation type. A modulated light beam emitted by a light source is conducted through specimen atom vapor generated by a graphite atomizer. Wavelength of light undergone atom absorption is selected and spatially separated into a pair of linearly polarized light beams perpendicular to each other. The pair of the linearly polarized light beams separated are alternately passed through a chopper and received by a photoelectric conversion device to be converted into electric signals which are utilized for determining atomic absorption of the specimen. The phase of modulation of light radiated from the light source is synchronized with phase of a current supplied to the graphite atomizer for heating thereof and the switching timing of the chopper.

Abstract: An electrothermal atomiser comprises a graphite cuvette (5) in which a probe (6) is inserted by an actuator (7). The cuvette is gripped by jaws (15) through which an electrical power supply is connected to resistively heat the cuvette (5). The probe (6) is formed from electrographite and may have a flat or profiled head portion on which the sample is deposited by means of a dosing tube (8).

Abstract: A cuvette consisting of a basic hollow member of pyrolytic graphite which is treated at least on the outside surface by a local mechanical abrasion is provided for use in atomic absorption spectroscopy. Since the mechanically treated surfaces may form the inner and outer surfaces of the cuvette, it has been found that the cuvette need not be after-coated or sealed with pyrolytic graphite, but may be of a finally finished form following this mechanical abrasion. Accordingly, cuvettes of substantially smaller wall thicknesses, and substantially smaller mass, are formed with the same or even increased rigidity than commercially available graphite cuvettes which may have or not have a pyrolytic graphite coating.

Abstract: A dual power-supply system is used to produce a sharp rise-time characteristic and a high steady-state temperature in a platinum ribbon pyrolysis probe. First, a small "boost" power supply generates a very short, high power pulse that is applied to the probe. Then, at its peak, the first power supply is effectively disabled and a second power supply is brought into play to maintain the power (and the temperature) in the probe at a high steady-state value approximating the peak value of the boost pulse.

Abstract: A method and apparatus for mounting the tubular furnace of spectroscopic apparatus to enable a protective atmosphere. The furnace is supported within the housing by annular electrodes engaging opposite ends of the furnace and an annular chamber surrounds the furnace for substantially its full length. A gas feed chamber adjacent each end of the furnace communicates with the respective adjacent end of the furnace through the central opening of the adjacent electrode and also communicates with the adjacent end of the annular chamber through passages provided in the adjacent electrode. Gas is fed simultaneously from each feed chamber into each end of the furnace and annular chamber to flow axially therealong for discharge through an opening in a wall of the housing located intermediate the furnace ends.

Abstract: A cuvette for atomic absorption spectrometry includes a tube of pyrolytic graphite, electrographite or vitreous carbon with flanges provided at the ends of the tube, or in the proximity thereof, and having a common envelope of pyrolytic graphite. The flanges consist of solid layers of pyrolytic graphite in which the layer planes of the pyrolytic graphite are either directed perpendicularly to the longitudinal axis of the tube, or extend everywhere parallel to the longitudinal axis and the surface of the tube. Cuvettes with flanges having an orientation of the solid layer planes directed perpendicularly to the longitudinal axis of the tube are considered and operate as "fast", whereas those having an orientation extending everywhere parallel to the longitudinal axis are considered.

Abstract: In a method for introducing a sample into a graphite tube in flameless atomic absorption spectroscopy a lamella- or crucible-like sample carrier is introduced into the graphite tube from the end face in axial direction. Drying and ashing of the sample is effected outside the graphite tube. The sample carrier may be heated indirectly by radiation or directly by electric current being passed therethrough.

Abstract: A cuvette having a thin-walled basic member of pyrolytic graphite is provided with annular graphite components in proximity to its ends. These parts are connected to form a unit which is further coated by an enveloping pyrolytic graphite coating. This cuvette having flanged parts is simpler to electrically contact and is mechanically stable.

Abstract: The atomizer of the present invention serves for generating free atoms and an atomic cloud by heating a sample for analysis. The device includes a preferably tubular cuvette for receiving the sample, and the cuvette consists either of a basic body of carbon, which is enveloped by a pyrolytic graphite layer, or only of pyrolytic graphite layers. An electric supply unit for Joule heating the cuvette is in contact with the cuvette by contact members. In order to achieve a radial temperature distribution in the cuvette such that the inner wall of the cuvette is at an essentially higher temperature than the outer wall of the cuvette, the contact surfaces of the cuvette and the contact surfaces of the contact members contact each other in such a manner that the electric current applied during operation of the atomizer preferably flows through the inner wall of the cuvette.

Abstract: A lamella-shaped sample carrier is attached to a tubular carriage and is movable into a graphite tube of a graphite tube cuvette from the end fact below the measuring light beam of an atomic absorption spectrophotometer. The carriage with the sample carrier is movable between an inner position, a dosing position and an outer position. The sample carrier is electrically heated in any position by means of busses. Drying and ashing of the sample take place outside the graphite tube. The graphite tube is then heated to atomizing temperature, while the sample carrier is in its outer position. Subsequently, the sample carrier is advanced into the inner position and heated itself. Thus, rapid atomization of the sample is achieved.

Abstract: A method and apparatus are disclosed for concentrating a selected element of a sample in a furnace or electrothermal atomizer for atomic spectroscopy. The apparatus includes a heating receptacle comprised of materials capable of withstanding the temperatures of atomization of such a sample. The apparatus further includes a means for heating the receptacle to the temperatures of atomization and a means for selectively cooling a selected location of the receptacle to a temperature below the vaporization temperature of the desired element in order to selectively condense the element at the location.

Abstract: A method relating to deposition of a liquid sample mixture in the tubular furnace of a spectrophotometer. The method involves drawing a quantity of each ingredient of the sample mixture into a conduit in a predetermined sequence and also drawing a slug of air into the conduit immediately following the uptake of each ingredient. In the result, a segmented fluid stream is created in which a slug of air separates each two adjacent ingredient segments. The conduit is initially filled with a rinsing fluid and the segmented fluid stream displaces some of that rinsing fluid from the conduit. A slug of air separates the rinsing fluid from the segmented stream. The segmented stream is then discharged in a single operation into the furnace of the spectrophotometer so that mixing of the ingredients occurs at or adjacent the furnace surface.

Abstract: An apparatus useful for flameless atomic absorption spectroscopy includes a sample carrier adapted for receiving non-gaseous sample material and means for radiantly heating the sample carrier to effect the uniform thermal decomposition thereof.

Abstract: An apparatus for atomizing a sample comprises a cuvette of heating material into which a sample is introduced, a pair of electrodes of supplying an electric current to the cuvette, thereby heating and atomizing the sample, supports of supporting the pair of the electrodes, a means for supplying light to the atomized sample and a means of slidably maintaining at least one of the pair of the electrodes against the cuvette in a predetermined range of contact pressures, where the heating temperature of the cuvette can be maintained constant with improved reproducibility of analytical values.

Abstract: An apparatus for enriching a sought element from a solution for flameless atomic absorption spectroscopy includes a constant voltage current source. The solution is enriched by electrodepositing the sought element therefrom and integrating the current with respect to time.

Abstract: The invention provides an improved method and apparatus for reduction of matrix interference in an electrothermal atomizer for atomic absorption spectroscopy. In a carbon rod atomizer within which a sample to be analyzed is atomized to the atomic state, the graphite furnace tube is electrothermally heated from the ends to the center where the sample is located. This provides sufficient thermal energy for complete decomposition of the sample molecules to the atomic state. In a first apparatus embodiment two-pronged substantially Y-shaped graphite electrode support holders for the graphite furnace tube are provided. In a second apparatus embodiment a double-walled graphite furnace tube is provided.

Abstract: A chamber useful with an atomic absorption spectrometer includes at least two atomization means installed therein. The means can be serially aligned with the measuring beam or arranged parallel to the axis thereof.

Abstract: An apparatus useful in the flameless atomic absorption spectroscopy analysis of a sample includes an electrically conductive sample carrier adapted to be heated whereby drying and ashing steps can be performed by passing an electric current therethrough. By use of such an apparatus, the temperature at which the ashing process occurs can be controlled.

Abstract: A sample manipulation system for spectrometers is disclosed in which an electrically conductive filament is arranged to receive and hold a liquid containing sample. Various levels of electrical power are employed to heat the filament for such purposes as increasing the affinity of the filament for the liquid, evaporating the liquid after deposition, ashing the remaining sample, and exciting the sample. Separate contact points are provided for each power level as well as means to successively connect at least one end of the filament to each contact point.

Abstract: In a Zeeman atomic absorption spectrophotometer, an atomic absorption signal in an atomization stage is observed. The length of time between an instant at which the signal initially attains a predetermined absorbance and an instant at which the signal attains the same predetermined absorbance for the last time during the atomization stage is measured. By utilizing this time measurement as an indication of concentration, the concentration of the sample can be measured at higher concentrations than the limit concentration in the analysis by a conventional apparatus of this kind.

Abstract: Graphite capsules are supported in a flame in an atomic furnace between electrical current heating electrodes that are mounted in the faces of a pair of water-cooled housings, one of which may be pivoted by a pneumatic piston to facilitate removal and insertion of the capsules and which provides a constant and firm contact pressure against the capsule ends independently of capsule length or diameter variations.

Abstract: Method and apparatus for automatically depositing predetermined reproducible amounts of nebulized samples into a furnace atomizer of an atomic absorption spectrophotometer, the atomizer being provided with an aperture, wherein a plurality of sample containers containing samples to be analyzed are arranged and successively transported on a sample supporting device, with the sample containers being open at their upper ends. The samples are aspirated from the containers via a suitable means and into a nebulizer-mixing chamber device wherein they are nebulized and mixed until such time that the nebulized sample achieves full equilibrium therein. A means is provided for depositing the nebulized and now equilibrated sample from the chamber device through the aperture into the furnace atomizer.

Abstract: A method and apparatus for carrying out atomic spectroscopy, and particularly atomic absorption and atomic fluorescence spectroscopy. The method involves passing the emission spectrum of a light source through an atomized sample, changing the relationship between a selected emission line of the emission spectrum and a corresponding absorption line of the atoms of interest and measuring the absorption of that emission line by the sample before and after the aforementioned change in relationship. The change in emission and absorption line relationship can be effected by application of the Zeeman Effect, Stark Effect, or Doppler Effect. The apparatus, in one form, includes an electro-magnet operative to apply a magnetic field to the atomized sample and thereby cause splitting and shifting of the aforementioned absorption line, and the magnet is modulated to effect periodic variation of the spectral line relationship.

Abstract: Disclosed is a system for controlling the temperature of an atomizer for an element analyzer, said system comprising a birefringent prism arranged on the optical axis of radiant light emitted out of the atomizer, and a light sensor for detecting the radiant light which passes through said birefringent prism.

Abstract: In a device for the emission spectral analysis of samples, including an evaporating tube for receiving and thermally evaporating a sample, and a hollow cathode and anode for athermally exciting the evaporated sample, the evaporation tube forms said cathode. The anode and cathode are mounted adjacent one another in spaced apart relationship along the axis of the tube.

Abstract: A graphite tube assembly for use in the atomic absorption spectroscopic measurement of samples, particularly liquid samples, during the passage of a beam of radiation through a graphite tube is disclosed. The graphite tube assembly includes a graphite tube and a sample holding platform which are cooperatively adapted to allow the platform to be removed and reinserted, or exchanged with another platform, while maintaining a preselected orientation of the platform with respect to an inlet port extending through the wall of the graphite tube.

Abstract: A method and apparatus for simultaneous multielement atomic absorption analysis, comprising use of a continuum source and a high resolution echelle polychromator modified for wavelength modulation, and a high speed data acquisition system (SIMAAC). The method and apparatus is capable of measuring as many as 16 or more elements simultaneously with either flame, electrothermal or other means of atomization. Double beam operation and dynamic background correction are achieved on all channels. Linear dynamic range of up to six orders of magnitude can be achieved for each channel.

Abstract: Disclosed are methods and apparatus for concentrating a looked-for element from a solution for flameless atomic absorption spectroscopy. The tip of an electrode is dipped into a sample vessel containing the solution and an electric current is passed through the electrode and solution to electrodeposit the components of the solution on the electrode. The electrode with the electrodeposition is removed from the sample vessel and inserted into the graphite tube. The tube is then heated and the sample components electrodeposited on the electrode are atomized for analysis by the measuring beam of the atomic absorption spectrometer.

Abstract: A method of flameless atomic absorption analysis in which an element in a sample is measured by vaporizing the sample in a graphite crucible or cuvette and measuring the absorbance of the atomic vapor at a wavelength characteristic of the element. The method includes the steps of (1) successively introducing a preselected number of aliquots of the same sample into the graphite cuvette, (2) thermally pretreating each sample aliquot upon introduction to remove volatile or decomposable substances therefrom, and (3) vaporizing sample remaining in the cuvette for measurement only after performing the predetermined successive number of sample introduction and thermal pretreatment cycles.

Abstract: A method and apparatus for carrying out atomic spectroscopy, and particularly atomic absorption and atomic fluorescence spectroscopy. The method involves passing the emission spectrum of a light source through an atomized sample, changing the relationship between a selected emission line of the emission spectrum and a corresponding absorption line of the atoms of interest and measuring the absorption of that emission line by the sample before and after the aforementioned change in relationship. The change in emission and absorption line relationship can be effected by application of the Zeeman Effect, Stark Effect, or Doppler Effect. The apparatus, in one form, includes an electro-magnet operative to apply a magnetic field to the atomized sample and thereby cause splitting and shifting of the aforementioned absorption line, and the magnet is modulated to effect periodic variation of the spectral line relationship.