Infrared absorption spectrometry

One has seen that the number of individual components in a hydrocarbon cut increases rapidly with its boiling point. It is thereby out of the question to resolve such a cut to its individual components instead of the analysis by family given by mass spectrometry, one may prefer a distribution by type of carbon. This can be done by infrared absorption spectrometry which also has other applications in the petroleum industry. Another distribution is possible which describes a cut in tei ns of a set of structural patterns using nuclear magnetic resonance of hydrogen (or carbon) this can thus describe the average molecule in the fraction under study. 

The methods of choice for beryUium oxide in beryUium metal are inert gas fusion and fast neutron activation. In the inert gas fusion technique, the sample is fused with nickel metal in a graphite cmcible under a stream of helium or argon. BeryUium oxide is reduced, and the evolved carbon monoxide is measured by infrared absorption spectrometry. BeryUium nitride decomposes under the same fusion conditions and may be determined by measurement of the evolved nitrogen. Oxygen may also be determined by activation with 14 MeV neutrons (20). The only significant interferents in the neutron activation technique are fluorine and boron, which are seldom encountered in beryUium metal samples. 

Total carbon in beryUium is determined by combustion of the sample, along with an accelerator mixture of tin, iron, and copper, in a stream of oxygen (15,16). The evolved carbon dioxide is usuaUy measured by infrared absorption spectrometry. BeryUium carbide can be determined without interference from graphitic carbon by dissolution of the sample in a strong base. BeryUium carbide is converted to methane, which can be determined directly by gas chromatography. Alternatively, the evolved methane can be oxidized to carbon dioxide, which is determined gravimetricaUy (16). 

Farmer VC (1978) Water on partial surfaces In Greenland DJ and Hayes MHB (eds) The chemistry of soil constituents. Wiley, New York, pp 405 49 Farmer VC, Russel JD (1967) Infrared absorption spectrometry in clay studies. Clays Clay Miner. 15 121-142. 

Direct methods for determining the combinational form of an element or its oxidation state include infrared absorption spectrometry, X-ray diffraction and, more recently, electron paramagnetic resonance - nuclear magnetic resonance -and Mossbauer spectrometry. With such techniques the combinational forms of major elements in soil components such as clay minerals, iron, manganese and aluminium oxyhydroxides and humic materials and the chemical structures of these soil components have been elucidated over the past 50 years. These direct, mainly non-destructive, methods for speciation are dealt with in some detail in Chapter 3 and are not further discussed here. 

Although infrared absorption spectrometry can be used to observe rotational spectra or even electronic spectra, we will limit ourselves here to examining molecular vibrational spectra, since these are the most frequently encountered in studying solid phase catalysts. 

K. Nakanishi, Infrared Absorption Spectrometry. Holden-Day, San Francisco, California, 1962. 

Deliens M, Delhal J, Tarte P (1977) Metamictization and U-Pb systematics-a study by infrared absorption spectrometry of Precambrian zircons. Earth Planet Sci Lett 33 331-344... 

Several commercial evidential breath alcohol measurement devices are available. The principle of measurement is either infrared absorption spectrometry (most common), dichromate-sulfuric acid oxidation-reduction (photometric), GC (flame ionization or thermal conductivity detection), electrochemical oxidation (fuel cell), or metal-oxide semiconductor sensors. A list has been published of DOT-approved breath alcohol devices.Some of these devices are approved for screening only. In this case, the second or confirmatory breath alcohol determination must be performed with an approved evidential breath alcohol analyzer. Breath alcohol devices may also be used for the medical evaluation of patients at the point of care (e.g., emergency department). A Fourier transform infrared point-of-care breath analyzer capable of measurement of... 

CuiF, J. P., Dauphin, Y., Berthet, P. Jegoudez, J. 2004. Associated water and organic compounds in coral skeletons quantitative thermogravimetry coupled to infrared absorption spectrometry. Geochemistry, Geophysics, Geosystems, 5, 11. doi 10.1029/2004/GC000783. 

In addition to ultraviolet and visible spectrophotometry, various other methods can be used to study the complexes cryoscopy, differential vapour pressure measurements, and infrared absorption spectrometry. , P25i- 256... 

Lauer, J.L. and Rosenbaum, E.J., Near-infrared absorption spectrometry, Appl Spectrosc., 6(5), 29-46, 1952. 

G.T. Merklin, P.R. Griffiths, "Effect of microscopic surface roughness in surface-enhanced infrared absorption spectrometry", J. Phys. Chem. B, 1997, 707(30), 5810-5813. 

M. L. Adams, Rapid Detection of Phthalic Acid Isomers and Benzoic Acid in Alkyd Resins by Infrared Absorption Spectrometry, USDC Report PB 1315W, October 1957. 

H. Powell and N. Evans, Variable Thickness Cell for Infrared Absorption Spectrometry, Fourth World Petrol. Congr., Rome, 1955, Proc., Sect. V, 371-378 (in English). 

Schwarcz, H. P., and E. L. Speelman, 1965. Determination of sulphur and carbon coordination in scapolite by infrared absorption spectrometry. Am. Mineralogist 50 656. 

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