Abstract: A method for coating a graphite tube for use in atomic absorption spectroscopy includes forming a layer of an adhesive volatile material on the tube. An inert material, in the form of a powder, is applied to the layer and heated to pyrolyze the inert material. Thereafter, the graphite tube is coated with pyrolytic graphite.

Abstract: A fluid activated pump that is particularly well suited for use in analytic machines of the type that need to accurately meter quantities of sample solutions. The pump, which includes a pump piston driven by a power piston, is powered either hydraulically or pneumatically. Also included in the pump is a displacement adjustment piston, which is either hydraulically or pneumatically controlled, and which, through a suitable shaft-type linkage, can adjust the length of the power piston's stroke, and thus permit either a large or small displacement of the pump piston. The fact that the pump piston's displacement can be changed means that the pump of the present invention can more efficiently meter solutions into various desired ratios, and can reduce the chance of cross-contamination of sample solutions by dispensing a large amount of rinsing solution after dispensing a relatively small amount of sample solution.

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: Disclosed is a system for the measurement of the atomic absorption of gaseous samples including a reaction vessel and conduits for supplying liquid sample, carrier gas and a reagent to the vessel. A discharge conduit is coupled between the reaction vessel and the measuring cell of an atomic absorption spectrometer. The reaction vessel has a drain conduit and a relief valve in the drain conduit. Control means are provided for controlling the flow of liquid sample, carrier gas, reagent and gaseous sample through the corresponding conduits in accordance with the predetermined program for making consecutive measurements. A pressure sensor is provided for sensing pressure in the reaction vessel above a specified pressure indicative of incomplete draining of the vessel and below a specified pressure indicative of substantially complete draining of the vessel.

Abstract: An automatic sampling apparatus for withdrawing samples from a continuously flowing liquid for analysis by a flameless atomic absorption spectrometer includes a sample vessel which, at predetermined times, receives pumped samples of the liquid to be tested, a neutral dilutant liquid, or a calibrated liquid for recalibrating the spectrometer system. A probe having a pipette-like tip is mechanically actuated to dip into the sample vessel and an intake and dispensing pump connected to the probe draws a small sample into the probe tip whereupon the probe mechanism lifts and rotates the probe and inserts the tip into the graphite atomizer tube of the atomic absorption spectrometer. The probe mechanism then returns the probe where it is first flushed with a flushing liquid pumped through the probe and is then returned to the sample vessel to draw the next test sample.

Abstract: Disclosed is an apparatus and method for using same for atomic absorption determination of volatile, thermally decomposable compounds. The test sample is converted to a gaseous sample in a reaction vessel with an inert gas atmosphere. The gaseous sample in the inert gas is then introduced into a heatable measuring cell arranged in the ray path of an atomic absorption spectrometer. To further assist decomposition, the inert gas is heated prior to entering the measuring cell.