Fourier Transform-infrared Technology

Blackwood, T. R. "An Evaluation of Flare Combustion Efficiency Using Open-Path Fourier Transform Infrared Technology." Journal of Air Waste Management Association 50, no. 10 (2000) 1714-22. 

For the experiments in which decay rates are used to determine individual NO3 radical reaction rate constants, N O, NO and the organics are quantitatively monitored by Fourier transform infrared technology (FT-IR) spectroscopy. For the relative rate constant studies, the reacting organics are analysed prior to and during these reactions by gas chromatography. 

Fourier transform spectroscopy technology is widely used in infrared spectroscopy. A spectrum that formerly required 15 min to obtain on a continuous wave instrument can be obtained in a few seconds on an FT-IR. This greatly increases research and analytical productivity. In addition to increased productivity, the FT-IR instrument can use a concept called Fleggetts Advantage where the entire spectrum is determined in the same time it takes a continuous wave (CW) device to measure a small fraction of the spectrum. Therefore many spectra can be obtained in the same time as one CW spectrum. If these spectra are summed, the signal-to-noise ratio, S/N can be greatly increased. Finally, because of the inherent computer-based nature of the FT-IR system, databases of infrared spectra are easily searched for matching or similar compounds. 

CAUTION Books can have a hard time keeping up with advances in computer technology. For example, here is how the sixth edition of Fundamentals of Analytical Chemistry described Fourier-transform infrared spectrometers in 1992. 

It is clear that the introduction of the IR FPA detector has brought Fourier transform infrared (FTIR) microscopy with a thermal source to a new and exciting stage of development. This is illustrated in the other chapters of this volume. Our purpose in this chapter is to address how IR FPA technology could be combined with the synchrotron source to advance IR spectroscopic imaging in ways that would prove quite difficult with a conventional thermal source. To address this question, we will need to understand the detailed nature of the synchrotron IR source, the optical... 

Fourier transform infrared spectroscopy negative ion spectroscopy and immunochemical technology are the subjects of several chapters. A chapter on cleanup presents a general challenge for all types of analytical techniques. Chemical derivatization of pesticides and metabolites enhances the detectability and ability to analyze small quantities of pesticide residues. 

Fourier-Transform Infrared (FTIR) spectroscopy as well as Raman spectroscopy are well established as methods for structural analysis of compounds in solution or when adsorbed to surfaces or in any other state. Analysis of the spectra provides information of qualitative as well as of quantitative nature. Very recent developments, FTIR imaging spectroscopy as well as Raman mapping spectroscopy, provide important information leading to the development of novel materials. If applied under optical near-field conditions, these new technologies combine lateral resolution down to the size of nanoparticles with the high chemical selectivity of a FTIR or Raman spectrum. These techniques now help us obtain information on molecular order and molecular orientation and conformation [1],... 

Particle diameter Inductively coupled plasma-optical emission spectrometry (ICP-OES) Fourier transform infrared spectrometry Mass spectrometry X-ray fluorescence Extended X-ray absorption fine structure (EXAFS) spectroscopy X-ray absorption near edge (XANES) spectroscopy Static and dynamic laser light scattering Scanning probe technologies... 

Improvements in column technology, detector sensitivity and the development of new detection systems, have made possible the routine separation of picomole quantities of nucleic acid components in complex physiological matrices. The very sensitivity of most LC systems, however, which is invaluable in the analysis of biological samples, is often the limiting factor because of inadequate or ambiguous identification methods. Although tremendous advances have been made in the on-line combination of HPLC with spectroscopic techniques [e.g., mass spectrometry, Fourier transform infrared (FT/IR), nuclear magnetic resonance], their application has not become routine in most biochemical and biomedical laboratories. 

IR spectra were taken at room temperature (300 K) and liquid-helium temperatures (5-15 K), using a Bomem DAS Fourier transform infrared (FTIR) spectrometer and an InSb detector. For the low-temperature measurements, a Janis continuous-flow liquid-helium cryostat with wedged, IR-transparent windows was utilized. Hall-effect measurements, in the Van der Pauw geometry, were performed at room temperature using a system from MMR Technologies. Wires were attached to the ZnO using silver paint, which provided adequate Ohmic contacts for the electron concentrations (10 cm ) in these samples. 

Traditionally, flavonoids have been separated and analyzed by HPLC and gas chromatography (GC). However, recent developments of SFC may permit a more accurate and complete analysis of plant phenolic compounds. Supercritical fluid chromatography brings together the advantages of both HPLC and GC techniques because it may be readily employed in the analysis of nonvolatile and thermolabile compounds and provides facile coupling to detector technologies such as mass spectrometry and Fourier transform infrared (FT-IR) spectroscopy. In recent years, SFC has been used to separate flavonoid compounds, most of which are polymethoxylated flavones and polyhydroxylflavonoids. 

Fourier transform infrared (FT-IR) spectroscopy is now one of the most popular techniques in analytical chemishy, this technology having several advantages compared to conventional dispersive infrared inshuments. Developments in instrument hardware, in computer software (usually by the instrument manufacturers) and in computing power generally has resulted in very powerful data collection and data handling systems for the analysis and characterisation of all sorts of materials including colorants. 

Figure 2 gives a scheme illustrating some applications in geochemistry and technology where surface reactivity (kinetics of dissolution, catalytic activity, photochemical activity) depends on surface structure, expecially on surface coordination. It has been shown by various spectroscopic techniques [electron-spin resonance (ESR), electron double-resonance spectroscopy (ENDOR), electron-spin echo modulation (e.g., see Motschi, 1987), Fourier transform infrared spectroscopy (Zeltner et al., 1986), and in situ X-ray absorption studies of surface complexes (EXAFS) (Hayes et al., 1987 Brown, 1989)] that inner-sphere... 

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