Spark source emission spectroscopy

The predorninant method for the analysis of alurninum-base alloys is spark source emission spectroscopy. SoHd metal samples are sparked direcdy, simultaneously eroding the metal surface, vaporizing the metal, and exciting the atomic vapor to emit light ia proportion to the amount of material present. Standard spark emission analytical techniques are described in ASTM ElOl, E607, E1251 and E716 (36). A wide variety of weU-characterized soHd reference materials are available from major aluminum producers for instmment caUbration. 

Electric spark Varies with time Emission Spark-source emission spectroscopy... 

Currently, the primary use of spark source emission spectroscopy is for the identification and analysis of metals and other conducting materials. Detection is often carried out with a polychromator equipped with photomultiplier tubes, but a number of vendors offer spectrometers with array detectors as well. In addition, several modern multichannel instruments arc now equipped with interchangeable sources that permit excitation by plasmas, arcs, sparks, glow discharge, and lasers. High-voltage sparks have also become... 

Quantitative aluminum deterrninations in aluminum and aluminum base alloys is rarely done. The aluminum content is generally inferred as the balance after determining alloying additions and tramp elements. When aluminum is present as an alloying component in alternative alloy systems it is commonly deterrnined by some form of spectroscopy (qv) spark source emission, x-ray fluorescence, plasma emission (both inductively coupled and d-c plasmas), or atomic absorption using a nitrous oxide acetylene flame. 

The minor and trace elements in coals are currently determined by several techniques, the most popular of which are optical emission and atomic absorption spectroscopy. Neutron activation analysis is also an excellent technique for determining many elements, but it requires a neutron source, usually an atomic reactor. In addition, x-ray fluorescence spectroscopy, electron spectroscopy for chemical analyses (ESCA), and spark source mass spectroscopy have been successfully applied to the analyses of some minor and trace elements in coal. 

Despite these warnings of Craddock, which also apply to other mined and smelted metals like silver and iron, there have been serious attempts to glean locational information from analytical data. Berthoud, in his thesis research and in a paper published with several collaborators using plasma emission and spark source mass spectroscopy, analyzed the multivariate compositional data of copper ores from more than 25 copper mines in Iran, that would have been important in early (4th and 3rd millennium) metallurgy. Their feeling was that the Craddock Assumption 1) was satisfied well enough and furthermore that it was possible to trace certain 4th millennium objects from Susa to a native copper source at Talmessi. Of course, with native copper, Craddock Assumptions 2) and 3) were not tested. 

F.K. Fong, Nonradiative processes of rare-earth ions in crystals 317 J.W. O Laughlin, Chemical spectrophotometric and polarographic methods 341 S.R. Taylor, Trace element analysis cf rare earth elements by spark source mass spectroscopy RJ. Conzemius, Analysis of rare earth matrices by spark source mass spectrometry 377 37D. E.L. DeKalb and V.A. FasseL Optical atomic emission and absorption methods 405 37E. A.P. D Silva and V.A. Fassel, X-ray excited optical luminescence of the rare earths 441 F.W.V. Boynton, Neutron activation analysis 457... 

This chapter describes the basic principles and practice of emission spectroscopy using non-flame atomisation sources. [Details on flame emission spectroscopy (FES) are to be found in Chapter 21.] The first part of this chapter (Sections 20.2-20.6) is devoted to emission spectroscopy based on electric arc and electric spark sources and is often described as emission spectrography. The final part of the chapter (Sections 20.7-20.11) deals with emission spectroscopy based on plasma sources. 

Actinide metal samples are characterized by chemical and structure analysis. Multielement analysis by spark source mass spectrometry (SSMS) or inductively coupled argon plasma (ICAP) emission spectroscopy have lowered the detection limit for metallic impurities by 10 within the last two decades. The analysis of O, N, H by vacuum fusion requires large sample, but does not distinguish between bulk and surface of the material. Advanced techniques for surface analysis are being adapted for investigation of radioactive samples (Fig. 11) ... 

Recently, a very important development has been made to enhance the ease of manipulation and the range of applicability of emission spectroscopy to trace metal analysis. This development is the plasma source which can be employed as an. accessory source in most direct reading emission spectrometers in place of the arc or spark or may be incorporated directly in the design of the spectrometer by the manufacturer. This development has been discussed in detail in the recent literature ( 9,53-58). 

Several other methods have been used to determine the trace elements in the mineral matter of coal, as well as in whole coal and coal-derived materials. These methods include spark-source mass spectrometry, neutron activation analysis, optical emission spectroscopy, and atomic absorption spectroscopy. 

Finally, the black-brown americium oxide is sieved through a 170 mesh 7.6 cm screen on a mechanical shaker. A complete analysis is done to determine whether the Am02 meets the required product specifications. The analysis of representative batches of americium oxide produced at LASL is shown in Table II. Radiochemistry, emission spectroscopy, calorimetry, and spark source mass spectrometry are used in the analysis of the Am02. Providing the Am02 meets all of the product specifications, it is prepared for shipment. Product not meeting these specifications is recycled through the process at the proper entry point. 

Tt may be safe to say that the interest of environmental scientists in airborne metals closely parallels our ability to measure these components. Before the advent of atomic absorption spectroscopy, the metal content of environmental samples was analyzed predominantly by wet or classical chemical methods and by optical emission spectroscopy in the larger analytical laboratories. Since the introduction of atomic absorption techniques in the late 1950s and the increased application of x-ray fluorescence analysis, airborne metals have been more easily and more accurately characterized at trace levels than previously possible by the older techniques. These analytical methods along with other modem techniques such as spark source mass spectrometry and activation analysis... 

In atomic emission spectroscopy, the radiation source is the sample itself. The energy for excitation of analyte atoms is supplied by a plasma, a flame, an oven, or an electric arc or spark. The signal is the measured intensity of the source at the wavelength of interest. In atomic absorption spectroscopy, the radiation source is usually a line source such as a hollow cathode lamp, and the signal is the absorbance. The latter is calculated from the radiant power of the source and the resulting power after the radiation has passed through the atomized sample. 

The major disadvantage of arc/spark emission spectroscopy is the instability of the excitation source. This problem can be virtually eliminated by the use of a plasma torch. The most common commercially available method uses an inductively coupled plasma (ICP), which is also called RF plasma, to excite the sample (13-19). The resulting spectrometers (Fig. 4) can simultaneously measure up to 60 elements with high sensitivity and an extraordinarily wide linear dynamic range. 

Spectral methods (spark source mass spectrometry SSMS, secondary ion mass spectrometry SIMS, inductively coupled argon plasma for emission spectroscopy ICAP-ES) which avoid separation steps are increasingly applied for multi-element analysis. Hot extraction is used for 0, N, H determinations. Oxygen is also determined by activation analysis, nitrogen after adaptation of classical methods (micro-Kjeldahl). Combination and comparison of different, independent methods are desirable, but hampered by the often limited availability of samples of actinides. 

X-ray fluorescence spectroscopy has been used to determine 50 ppb of nickel and vanadium after they have been concentrated on ion exchange resins (5, 6). Emission spectroscopy has been used but is only semi-quantitative at the nanogram/gram levels of interest to the Project. Nevertheless, the technique may be useful as a screening tool. Two relatively new instrumental techniques—spark source mass spectrometry (7) and kinetics of metal-catalyzed reactions (8)—can measure extremely low levels of nickel and vanadium, but they have not been utilized to any appreciable extent. 

Absorption spectrophotometry Fluorescence methods Atomic-absorption methods Flame photometry Neutron activation analysis Emission spectroscopy Spark source mass spectrometry Reaction gas chromatography of chelates using electron-capture detection... 

Chavacteristic Neutron Activation Analysis X-Ray Fluorescence Emission Spectroscopy Flame Emission Atomic Absorption Spark Source Mass Spectrometry... 

This chapter deals with optical atomic, emission spectrometry (AES). Generally, the atomizers listed in Table 8-1 not only convert the component of samples to atoms or elementary ions but, in the process, excite a fraction of these species to higher electronic stales.. 4, the excited species rapidly relax back to lower states, ultraviolet and visible line spectra arise that are useful for qualitative ant quantitative elemental analysis. Plasma sources have become, the most important and most widely used sources for AES. These devices, including the popular inductively coupled plasma source, are discussedfirst in this chapter. Then, emission spectroscopy based on electric arc and electric spark atomization and excitation is described. Historically, arc and spark sources were quite important in emission spectrometry, and they still have important applications for the determination of some metallic elements. Finally several miscellaneous atomic emission source.s, including jlanies, glow discharges, and lasers are presented. 

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