Liquid chromatography and infrared spectroscopy

GC- and LC-MS (Fig. 2), although others have also used other techniques including Fourier transform infrared spectroscopy, thin layer chromatography, high-pressure liquid chromatography, and Raman spectroscopy. The major techniques as judged by current number of publications will be discussed below. 

Pyrolysis, combined with gas or liquid chromatography and infrared and mass spectroscopy, is a powerful tool for studying polymer fragments. A 14-page bibliography covering selected reports from 1973 to 1980 is available at no cost (195). and the method is reported on by Liebman (, 128). 

Nair and Luna (1968) have isolated a-tocopherol from rat heart muscle and have characterized it by means of gas-liquid chromatography and infrared and mass spectroscopy. The infrared spectra of trimethylsilyl ethers of known standards and unknown extracts were identical. They were characterized by the lack of an OH... 

Analysis of amphetamines is commonly accomplished using a number of different methodologies. These include techniques such as thin-layer chromatography (TLC), gas chromatography (GC), liquid chromatography (LC), infrared spectroscopy, and mass spectrometry (MS). In addition, several different immvmoassays are commonly used for the analysis of amphetamines. 

In the case of heterogeneous polymers the experimental methods need to be refined. In order to analyze those polymers it is necessary to determine a set of functions / (M), which describe the distribution for each kind of heterogeneity i This could be the mass distributions of the blocks in a diblock copolymer. The standard SEC methods fail here and one needs to refine the method, e.g., by performing liquid chromatography at the critical point of adsorption [59] or combine SEC with methods, which are, for instance, sensitive to the chemical structure, e.g., high-pressure liquid chromatography (HPLC), infrared (IR), or nuclear magnetic resonance spectroscopy (NMR) [57],... 

Modern analytical techniques have been developed for complete characterization and evaluation of a wide variety of sulfonic acids and sulfonates. Titration is the most straightforward method of evaluating sulfonic acids. Spectroscopic methods for sulfonic acid analysis include ultraviolet spectroscopy, infrared spectroscopy, and lH and l3C nmr spectroscopy. Modem separation techniques of sulfonates include liquid chromatography and ion chromatography. See also Chromatography. 

Reactions were carried out in the liquid phase using 100 % HNOj from MERCK. Acidic clays (Slid CHEMIE - Munich FRG) and dessicants (PROLABO) were of commercial grade and used without further purifications, besides thermal treatments if needed. All compounds were analysed by gaz chromatography and their structures confirmed by mass spectrometry and infrared spectroscopy. 

Studies in the area of chemical definition of starting materials began more than 10 years ago (23). In addition to wet chemistry, the laboratory measurements currently used for this purpose are differential scanning calorimetry (DSC), high-performance liquid chromatography (HPLC), gel permeation chromatography (GPC), infrared spectroscopy (IR), and rheology. 

Traditional instrumental techniques, such as nuclear magnetic NMR, mass spectrometry infrared (IR) spectroscopy, ultraviolet-visible spectrophotometry, and gas and liquid chromatography and size-exclusion chromatography, are used extensively for purity assessment and molecular structure and molecular weight measurements of monomers and polymers [61]. 

Several triterpenes and the tetraterpene perhydro-/ -carotene have been identified (Murphy et ai, 1967) in the branched-cyclic hydrocarbon fraction of Green River (Eocene) shale. This was the first time that a tetraterpene had been isolated from a geological sample, although sesqui-, di-, and triterpenes had been identified in this and other sediments. Gas-liquid chromatography, mass spectrometry, NMR, and infrared spectroscopy were used for identification. 

In the examination of plant waxes various analytical methods have been used, including ultraviolet and infrared spectroscopy, and thin-layer, column, and gas-liquid chromatographies (Eglinton and Hamilton, 1967). The infrared spectrum has been used to indicate hydroxy compounds, ketones, ethers, and lactones, as well as the more common esters and hydrocarbons. In the use of thin-layer or column chromatography, infrared spectra can be used to make sure that there is no carryover of one class of components into another. 

See also Atomic Absorption Spectrometry Flame Electrothermal. Atomic Emission Spectrometry Inductively Coupled Plasma. Color Measurement. Forensic Sciences Paints, Varnishes, and Lacquers. Gas Chromatography Pyrolysis. Infrared Spectroscopy Industrial Applications. Liquid Chromatography Size-Exclusion. Paints Water-Based. Spectrophotometry Organic Compounds. X-Ray Absorption and Diffraction X-Ray Diffraction - Powder. X-Ray Fluorescence and Emission Wavelength Dispersive X-Ray Fluorescence Energy Dispersive X-Ray Fluorescence. 

The importance of surface and chemical analysis techniques in electronics corrosion testing cannot be overstated. These powerful tools contribute to solving problems and elucidating corrosion mechanisms in simple and complex systems. Chemical analysis techniques include infrared (IR), ultraviolet (UV), and RAMAN spectroscopy X-ray diffraction atomic adsorption emission and mass spectroscopy gas and liquid chromatography and optical and transmission electron microscopy. Surface analytical techniques include electron spectroscopy for chemical analysis (ESCA), Auger, secondary ion mass spectroscopy (SIMS), and ion scattering spectroscopy (ISS). These important techniques used in conjunction with corrosion tests are described in another section of this manual. 

In all instances, there is a need to confirm the purity or stability of a particular sample before and after testing. Generally, the sponsor will assume these functions, but many private testing laboratories are associated with sophisticated analytical chemistry laboratories equipped with infrared spectrometry, gas chromatography, high-pressure liquid chromatography, and gas chromatography-mass spectroscopy instruments. 

Kok, S.J. (2004) Coupling of Liquid Chromatography and Fourier-Transform Infrared Spectroscopy for the Characterization of Polymers. Ph.D. thesis. University of Amsterdam, Amsterdam. 

INFRARED TECHNOLOGY AND RAMAN SPECTROSCOPY - INFRARED TECHNOLOGY] (Vol 14) Hplc. See ITigh performance liquid chromatography. 

The modern electronic industry has played a very important role in the development of instrumentation based on physical-analytical methods As a result, a rapid boom in the fields of infrared, nuclear magnetic resonance (NMR), Raman, and mass spectroscopy and vapor-phase (or gas-liquid) chromatography has been observed. Instruments for these methods have become indispensable tools in the analytical treatment of fluonnated mixtures, complexes, and compounds The detailed applications of the instrumentation are covered later in this chapter. 

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