Arc emission spectroscopy

The boron nitride obtained in this study was characterized by infrared spectroscopy, powder x-ray diffractometry and transmission electron microscopy. Trace elemental analyses were also performed by energy dispersive x-ray analysis and carbon arc emission spectroscopy. Representative spectra are displayed in Figures 2-4. 

DC Arc Emission Spectroscopy, values given in wt% Mahogany Zone C-a Tract, 100 x 200 mesh oil shale Instrumental Neutron Activation Analysis... 

Among the various types of atomic spectroscopy, only two, flame emission spectroscopy and atomic absorption spectroscopy, are widely used and accepted for quantitative pharmaceutical analysis. By far the majority of literature regarding pharmaceutical atomic spectroscopy is concerned with these two methods. However, the older method of arc emission spectroscopy is still a valuable tool for the qualitative detection of trace-metal impurities. The two most recently developed methods, furnace atomic absorption spectroscopy and inductively coupled plasma (ICP) emission spectroscopy, promise to become prominent in pharmaceutical analysis. The former is the most sensitive technique available to the analyst, while the latter offers simultaneous, multielemental analysis with the high sensitivity and precision of flame atomic absorption. 

Beginning in the 930s. a major portion of industrial laboratories throughout the world adopted spark and arc emission spectroscopy for elemental analysis of raw materials, intermediates, and finished products. In ihe early years, ihe only instrument available for this tvpe )f analysis was the speann raph with a photographic iilm or plate located at the k>cai plane v>r curve. 

Bulk chemical analysis X-ray fluorescence spectroscopy Atomic absorption spectroscopy Inductively coupled plasma emission spectroscopy Direct-current plasma emission spectroscopy Arc emission spectroscopy Gravimetry Combustion Kjeldahl Impurities... 

Production and quality control of uranium fuel rods used in nuclear power plants are monitored by DC arc emission spectroscopy. Trace elements in high-purity metal powders are measured for quality control purposes. Tungsten powder used to make light bulb hlament can be analyzed for trace elements by arc/spark emission spectroscopy without the need to dissolve the tungsten this eliminates the use of expensive and hazardous hydrofluoric acid. 

C1517. (2009). Standard test method for determination of metallic impurities in uranium metal or compounds by DC-Arc emission spectroscopy. West Conshohocken, PA ASTM. 

Emission spectroscopy is confined largely to the visible and ultraviolet regions, where spectra may be produced in an arc or discharge or by laser excitation. Absorption spectroscopy is, generally speaking, a more frequently used technique in all regions of the spectrum and it is for this reason that we shall concentrate rather more on absorption. 

Emission spectroscopy is a very useful analytical technique in determining the elemental composition of a sample. The emission may be produced in an electrical arc or spark but, since the mid-1960s, an inductively coupled plasma has increasingly been used. 

Aluminum is best detected quaUtatively by optical emission spectroscopy. SoHds can be vaporized direcdy in a d-c arc and solutions can be dried on a carbon electrode. Alternatively, aluminum can be detected by plasma emission spectroscopy using an inductively coupled argon plasma or a d-c plasma. Atomic absorption using an aluminum hoUow cathode lamp is also an unambiguous and sensitive quaUtative method for determining alurninum. 

Finished zinc and zinc aHoys are usuaHy analyzed for metals other than zinc by emission spectroscopy and the zinc determined by difference. ASTM method E 27 describes a technique using a dissolved sample and photographic detection. The internal standard is the zinc line at 267.0 nm. However, procedures using soHd samples are generaHy preferred and photoelectric detection often replaces optical detection. Samples are cast and machined on the surface where the arc is stmck. Up to 15 elements can be determined in a few minutes by modem automatic spectrometers. ASTM gives wet chemical methods for metals other than zinc (79). 

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. 

Previous experience in arc and spark emission spectroscopy has revealed numerous spectral overlap problems. Wavelength tables exist that tabulate spectral emission lines and relative intensities for the purpose of facilitating wavelength selection. Although the spectral interference information available from arc and spark spectroscopy is extremely useful, the information is not sufficient to avoid all ICP spectral interferences. ICP spectra differ from arc and spark emission spectra because the line intensities are not directly comparable. As of yet, there is no atlas of ICP emission line intensity data, that would facilitate line selection based upon element concentrations, intensity ratios and spectral band pass. This is indeed unfortunate because the ICP instrumentation is now capable of precise and easily duplicated intensity measurements. 

Automatic Atomic Emission Spectroscopy, 2nd edn, Slickers, K., Briihlsche Universitatsdmckerei, Giessen, 1993. A very useful practical guide to arc and spark methods in the metallurgical industry. 

The ashes were analyzed by emission spectroscopy using a d.c. arc and a Jarrell-Ash Wadsworth spectrograph. A visual comparison of line intensities with standard rock samples established the approximate elemental concentrations. Based on experience, the true content of any element is most probably within the range 2 to 0.5X the stated value. 

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). 

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