Emissivity flames

FLAME ATOMIC EMISSION, FLAME ATOMIC ABSORPTION,... 

Element Wavelength, nm Flame emission Flame atomic absorption Electrothermal atomic absorption Argon ICP Plasma atomic fluorescence... 

The section on Spectroscopy has been retained but with some revisions and expansion. The section includes ultraviolet-visible spectroscopy, fluorescence, infrared and Raman spectroscopy, and X-ray spectrometry. Detection limits are listed for the elements when using flame emission, flame atomic absorption, electrothermal atomic absorption, argon induction coupled plasma, and flame atomic fluorescence. Nuclear magnetic resonance embraces tables for the nuclear properties of the elements, proton chemical shifts and coupling constants, and similar material for carbon-13, boron-11, nitrogen-15, fluorine-19, silicon-19, and phosphoms-31. 

Flame emissivity Flame ionization Flameproofing cotton Flame resistance Flame-resistant fibers Flame retardancy Flame retardant... 

Summation of Separate Contributions to Gas or Flame Emissivity Flame emissivity g -t-, due to joint emission from gas and soot has already been treated. If massive-particle emissivity ., such as from fly ash, coal char, or carbonaceous cenospheres from heavy fuel oil, are present, it is recommended that the total emissivity be approximated by... 

Finally, and apart from the importance of micelles in the solubilization of chemical species, mention should also be made of their intervention in the displacement of equilibria and in the modification of kinetics of reactions, as well as in the alteration of physicochemical parameters of certain ions and molecules that affect electrochemical measurements, processes of visible-ultraviolet radiation, fluorescence and phosphorescence emission, flame emission, and plasma spectroscopy, or in processes of extraction, thin-layer chromatography, or high-performance liquid chromatography [2-4, 29-33],... 

Thornton JS, Anderson CA. 1968. Determination of residues of Di-Syston and metabolites by thermionic emission flame gas chromatography. J Agric Food Chem 16 895-898. 

Lundegardh vaporizer analychem A device used for emission flame photometry in which a compressed air aspirator vaporizes the solution within a chamber smaller droplets are carried into the fuel-gas stream and to the burner orifice where the solvent is evaporated, dissociated, and optically excited. Iun-d3,gard va-p3,rTz-or)... 

Chromatographic methods have included development of element-specific atomic emission, flame photometric, and flame chemiluminescent detectors. For example, a flame chemiluminescent phosphorus detector has been suggested for... 

Emission flame photometry-A. L. Levi and E. M. Katz, Clin. Chem., 1970,16, 840-842. 

Emission flame photometry-R. Robertson a/., Clinica chim. Acta, 1973,45, 25-31. 

Emission Flame Photometry. In blood or urine sensitivity 2 nmol/litre in blood, 30 nmol/litre in urine—R. Robertson et al, Clinica chim. Acta., 1973, 45, 25-31. In serum sensitivity 50 nmol/litre (comparison with atomic absorption spectrophotometry)—A. L. Levi and E. M. Katz, Clin. Chem., 1970, 16, 840-842. 

When new analytical tools become available, more often than not considerations of responsibility to the patient, practicality, and economy will keep the clinical chemist from accepting such newly developed techniques without careful deliberation. It appears that presently atomic abso tion spectroscopy is slowly finding entrance into medical research and service laboratories, and there is reason to expect that this technique will find wider use and greater application than emission flame spectroscopy. Virtually all metals, with very few exceptions, can be determined by atomic absorption spectroscopy. It is anticipated that this technique not only will replace currently used analytical methods for metals, but will also make feasible the routine determination of elements now impractical by conventional means. Furthermore, the operational stability of available instruments and the simplicity of actual performance of measiurements make this technique well suited for automation, by addition of an automatic sample feed and automatic recording. 

Following the work of Lundegardh in the twenties, emission flame spectroscopy became established as an analytical tool in almost every branch of science. Although hollow cathode tubes were first studied by Paschen (P2) in 1916, and although atomic absorption spectroscopy had found occasional application, notably in the mercury vapor detector W20), it remained for Walsh (W2) in Australia in 1955 to recognize the essential advantages inherent in absorption over emission methods and revive general interest in this technique. Shortly thereafter but apparently independently, Alkemade and Milatz (A2, A3) in Holland devised instruments and applied atomic absorption spectroscopy in their laboratory. Walsh and his co-workers have since contributed a remarkable volume of work on instrumentation and application, and patents are held by Walsh on his method in Australia, Europe, and America. 

The early workers in this field built their own apparatus, often assembling these from suitable units available from instruments for other purposes. Emission flame photometers have been converted into atomic absorption spectrophotometers by appropriate attachments consisting of specific light sources, choppers, and lenses, a principle also employed by some manufacturers. 

Herrmann and Lang (H3) studied various atomizers and recorded best results with a laboratory-built high pressure vaporizer. No ionization interference was seen in an air-propane flame and calibration curves were straight from 1 to 10 mg sodium per liter. Determinations were performed on serum diluted 1 20-1 200 and results agreed well with those concurrently obtained by emission flame photometry. 

The development of fast and accurate procedures for the determination of calcium in biological materials represents one of the important early achievements of atomic absorption spectroscopy. The diflBculties encountered with calcium in emission flame photometry are well known (Dll, L6, S6, SIO), but spectral interferences and extreme dependency on flame temperature, serious obstacles in emission, are either nonexistent or of lower importance in absorption. Chemical interferences, however. 

A simple emission flame photometer is adequate for Na and K while a more selective emission/absorbance system is necessary for Ca, Mg, and trace metals. The range of trace metals which can be analyzed (e.g., Cu, Zn, Fe, As, Pb, Co, Mo, Se, Cd, Hg) with an instrument depends on the efficiency of atomization, excitation, and light collection, as well as the intensity and stability of the background. Owing to the difficulty of obtaining complete stability of baseline and sensitivity, frequent standardization of instruments is usually necessary. This can... 

B18. Braman, R. S., Flame emission and dual flame emission-flame ionization detectors for gas chromatography. Anal. Chem. 38, 734-742 (1966). 

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