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Infrared spectroscopy generalities

Recall from above that an FTIR is a specific type of infrared spectrometer. Thus, FTIRs have advantages and disadvantages compared to other types of infrared instruments above and beyond the advantages and disadvantages of infrared spectroscopy generally, which was discussed above. [Pg.12]

Perhaps the most commonly used spectrometric method for analysis of viscous oils is infrared spectroscopy. General instructions for qualitative hydrocarbon type and functional group analysis are widely available. Papers have also been published for quantitative analysis of hydrocarbon types [/O]. FT-IR techniques have been reported for use in predictive maintenance programs to monitor the concentration of additives and degradation products in used oils [11 ]. [Pg.31]

In addition to covering Raman microscopy, this book has a wealth of information on Raman instrumentation in general. Elving P J and Winefordner J D (eds) 1986 Fourier Transform Infrared Spectroscopy (New York Wiley)... [Pg.1178]

Thermal Transducers Infrared radiation generally does not have sufficient energy to produce a measurable current when using a photon transducer. A thermal transducer, therefore, is used for infrared spectroscopy. The absorption of infrared photons by a thermal transducer increases its temperature, changing one or more of its characteristic properties. The pneumatic transducer, for example. [Pg.379]

The first anhydride plant in actual operation using methyl acetate carbonylation was at Kingsport, Tennessee (41). A general description has been given (42) indicating that about 900 tons of coal are processed daily in Texaco gasifiers. Carbon monoxide is used to make 227,000 t/yr of anhydride from 177,000 t/yr of methyl acetate 166,000 t/yr of methanol is generated. Infrared spectroscopy has been used to foUow the apparent reaction mechanism (43). [Pg.77]

The formation of such materials may be monitored by several techniques. One of the most useful methods is and C-nmr spectroscopy where stable complexes in solution may give rise to characteristic shifts of signals relative to the uncomplexed species (43). Solution nmr spectroscopy has also been used to detect the presence of soHd inclusion compound (after dissolution) and to determine composition (host guest ratio) of the material. Infrared spectroscopy (126) and combustion analysis are further methods to study inclusion formation. For general screening purposes of soHd inclusion stmctures, the x-ray powder diffraction method is suitable (123). However, if detailed stmctures are requited, the single crystal x-ray diffraction method (127) has to be used. [Pg.74]

Mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectroscopy are techniques of structure determination applicable to all organic molecules. In addition to these three generally useful methods, there s a fourth—ultraviolet (UV) spectroscopy—that is applicable only to conjugated systems. UV is less commonly used than the other three spectroscopic techniques because of the specialized information it gives, so we ll mention it only briefly. [Pg.500]

Naes, T., Isaksson, T., "Selection of Samples for Calibration in Near-Infrared Spectroscopy. Part I General Principles Illustrated by Example", Appl. Spec. 1989 (43) 328-335. [Pg.193]

In order to get the pore system of zeolites available for adsorption and catalysis the template molecules have to be removed. This is generally done by calcination in air at temperatures up to 500 °C. A careful study (ref. 12) of the calcination of as-synthesized TPA-containing MFI-type single crystals by infrared spectroscopy and visible light microscopy showed that quat decomposition sets in around 350 °C. Sometimes special techniques are required, e.g. heating in an ammonia atmosphere (ref. 13) in the case of B-MFI (boron instead of aluminum present) to prevent loss of crystallinity of the zeolite during template quat removal. [Pg.208]

There is great interest in developing molecular precursors for boron-nitrogen polymers and boron nitride solid state materials, and one general procedure is described in this report. Combinations of B-trichloroborazene and hexamethyldisilazane lead to formation of a gel which, upon thermolysis, gives hexagonal boron nitride. The BN has been characterized by infrared spectroscopy, x-ray powder diffraction and transmission electron microscopy. [Pg.378]

As already indicated above, what one may consider a surface depends on the property under consideration. Adhesion is very much an outer atomic layer issue, unless one is dealing with materials like fibreboard in which the polymer resin may also be involved in mechanical anchoring onto the wood particles. Gloss and other optical properties are related to the penetration depth of optical radiation. The latter depends on the optical properties of the material, but in general involves more than a few micrometer thickness and therewith much more than the outer atomic layers only. It is thus the penetration depth of the probing technique that needs to be suitably selected with respect to the surface problem under investigation. Examples selected for various depths (< 10 nm, 10 s of nm, 100 nm, micrometer scale) have been presented in Chapter 10 of the book by Garton on Infrared Spectroscopy of Polymer Blends, Composites and Surfaces... [Pg.676]

The vapor pressure at 0° (43 mm.) is generally a sufficient criterion for purity. (The checkers also used infrared spectroscopy and noted a trace of impurity of silicon tetrachloride.) Elemental analysis is readily accomplished by heating a weighed sample at 160° for 18 hours with a slight excess of water in a sealed glass tube. A 15 to 20% excess of water over that required by the equation ... [Pg.124]

In-situ Fourier transform infrared spectroscopy. The final technique in this section concerns the FTIR approach which is based quite simply on the far greater throughput and speed of an FTIR spectrometer compared to a dispersive instrument. In situ FTIR has several acronyms depending on the exact method used. In general, as in the EMIRS technique, the FTIR-... [Pg.111]

Generalized Two-Dimensional (2D) correlation analysis is a powerful tool applicable to data obtained from a very broad range of measurements, such as chromatography or infrared spectroscopy. Relationships among systematic variations in infrared spectra are obtained as a function of spectroscopic frequencies. In this paper, the variation is induced by the introduction of small doses of CO in the catalytic cell, inducing a pressure change and a modification of adsorbed CO concentration. The correlation intensities are displayed in the form of 2D maps, usually referred to as 2D correlation spectra. 2D correlation analysis can help us to solve the complexity of the spectra... [Pg.59]


See other pages where Infrared spectroscopy generalities is mentioned: [Pg.273]    [Pg.214]    [Pg.267]    [Pg.358]    [Pg.273]    [Pg.214]    [Pg.267]    [Pg.358]    [Pg.584]    [Pg.1264]    [Pg.1136]    [Pg.1143]    [Pg.270]    [Pg.43]    [Pg.446]    [Pg.624]    [Pg.8]    [Pg.23]    [Pg.82]    [Pg.28]    [Pg.126]    [Pg.348]    [Pg.5]    [Pg.404]    [Pg.362]    [Pg.363]    [Pg.1136]    [Pg.1143]    [Pg.95]    [Pg.151]    [Pg.315]    [Pg.316]    [Pg.29]    [Pg.123]    [Pg.113]    [Pg.243]    [Pg.10]    [Pg.463]    [Pg.185]    [Pg.248]    [Pg.499]   
See also in sourсe #XX -- [ Pg.339 , Pg.341 ]




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A Partial Listing of General References to Infrared Spectroscopy

General References to Infrared Spectroscopy

General spectroscopy

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