Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Fourier transform methodology

The tool extends the original GRAMM fast Fourier transformation methodology by employing smoothed potentials, refinement stage, and knowledge-based scoring... [Pg.445]

G. Eleury, G. Schlatter, and R. Muller, Non linear rheology for long branching characterization, comparison of two methodologies Fourier transform rheology and relaxation, Rheol. Acta, 44, 174—187, 2004. [Pg.849]

A rate enhancement effect due to secondary nucleation has been identified in the solution-mediated transformation of the 7-phase of (i)-glutamic acid to its / -phase [82]. In this study, the kinetics of the polymorphic transition were studied using optical microscopy combined with Fourier transform infrared, Raman, and ultraviolet absorption spectroscopies. The crystallization process of n-hexatriacontane was investigated using micro-IR methodology, where it was confirmed that single... [Pg.273]

Additionally, with the inclusion of computers as part of an instrument, mathematical manipulation of data was possible. Not only could retention times be recorded automatically in chromatograms but areas under curves could also be calculated and data deconvoluted. In addition, computers made the development of Fourier transform instrumentation, of all kinds, practical. This type of instrument acquires data in one pass of the sample beam. The data are in what is termed the time domain, and application of the Fourier transform mathematical operation converts this data into the frequency domain, producing a frequency spectrum. The value of this methodology is that because it is rapid, multiple scans can be added together to reduce noise and interference, and the data are in a form that can easily be added to reports. [Pg.31]

The methodology that involves instruments that utilize the interferometer and Fourier transformation mentioned in Section 8.6 has come to be known as Fourier transform infrared spectrometry (FTIR). [Pg.219]

The second approach is to perform traditional pre-formulational studies using full factorial or Plackett Burman experimental designs [15]. Here, the preferred analytical methodology tends to be thermal and spectroscopic, rather than chromatographic, although the latter methodologies are still utilised. Differential scanning calorimetry (DSC), isothermal calorimetry (ITC) or Fourier-transform infrared (FT-IR) spectroscopy have all been utilised successfully. [Pg.24]

Tejedor-Tejedor, M.L Yost, E.C. Anderson, M.C. (1990a) Characterization of benzoic acid and phenolic complexes at the goethite/ aqueous solution interface using cylindrical internal reflectance Fourier transform infrared spectroscopy. Part 5 Methodology. Langmuir 6 979-987... [Pg.635]

Application of nLFP techniques in the IR region has been available for well over a decade. In one approach, laser diodes are used to generate the monitoring beam and a fast IR detector employed. Alternatively, a step-scan spectrometer uses the same methodologies employed by normal Fourier transform infrared (FTIR) spectrometers, but spectral capture is much faster. [Pg.868]

ERNST. RICHARD R. (I933-). A native of Switzerland who won the Nobel prize in chemistry in 1991 for important methodological developments in NMR spectroscopy. He invented Fourier-transform NMR lET-NMR). which multiplied sensitivity It) to 100 times compared to dispersive instruments. He also devised two-dimensional NMR techniques, increasing resolution and enabling structure determinations of biologically important macromolecules. Ernst received his Pli.D from the Federal Technical Institute (ETH) in Zurich. Switzerland... [Pg.582]

A review of progress in the development of dispersive and Fourier transform VCD methodology has been provided recently by Keiderling [13]. Detailed descriptions of the dispersive and the double modulation FT-VCD instruments in his laboratory are presented. These two approaches to VCD measurement are compared and critiqued, with the relative advantages and disadvantages of each described. In the following subsections, we describe further details related to FT-VCD instrumentation as developed in our laboratory at Syracuse. [Pg.64]

In the author s opinion, the better approach to experimentally study the morphology of the silica surface is with the help of physical adsorption (see Chapter 6). Then, with the obtained, adsorption data, some well-defined parameters can be calculated, such as surface area, pore volume, and pore size distribution. This line of attack (see Chapter 4) should be complemented with a study of the morphology of these materials by scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning probe microscopy (SPM), or atomic force microscopy (AFM), and the characterization of their molecular and supramolecular structure by Fourier transform infrared (FTIR) spectrometry, nuclear magnetic resonance (NMR) spectrometry, thermal methods, and possibly with other methodologies. [Pg.85]

Simple and rapid spectroscopic methods, such as front-face fluorescence, attenuated total reflectance Fourier-transform infrared and nuclear magnetic resonance spectroscopies, have a great potential for investigation of the structure of fats in dairy products and of the relation between structure and texture. Although fluorescence, infrared and NMR spectroscopies are techniques, the theory and methodology of which have been exploited extensively in studies in both chemistry and biochemistry, the usefulness of these spectroscopies for molecular studies has not been yet fully recognized in food science. Fluorescence, infrared and NMR spectroscopies coupled... [Pg.705]

To benefit general readers, the discussion has been limited to methodologies that are accessible to nonspecialists and that can be carried out on commercially available spectrometers without special modifications. The chapter illustrates the principles of mass spectrometry by demonstrating how various techniques [MALDI, ESI, Fourier transform ion cyclotron resonance (FT-ICR), ion traps, and tandem mass spectrometry (MS-MS)] work. It also provides examples of utilizing mass spectrometry to solve biological and biochemical problems in the field of protein analysis, protein folding, and noncovalent interactions of protein-DNA complexes. [Pg.8]

However, the authors do not claim that these three main strategic lines in company of CETO functions constitute the unique way nor the best path to solve the molecular integral problem directed to find plausible substitutes of GTO functions. Other integration methods to deal with the present discussion can be used and analyzed, for instance Fourier, Laplace or Gauss transform methodology or any other possible choices and techniques available in the modem mathematical panoply. [Pg.121]

After their isolation by chromatographic techniques (anion-exchange chromatography, size exclusion, etc.), different analytical methodologies have been used to identify and quantify the polysaccharides in wine the most commonly used being the traditional methylation analysis followed by GC-MS (Doco and Bril-louet 1993). Polysaccharides have also been determined after solvolysis with anhydrous methanol containing HCl by GC-MS of their per-G-trimethylsilylated methyl glycosides (Vidal et al. 2003). Other techniques such as Fourier transform infrared spectroscopy (FTIR) have been more recently proposed (Coimbra et al. 2002,2005 Boulet et al. 2007). [Pg.244]

The IR and Raman spectra of partially hydrated proteins are a rich source of fundamental information on both water and protein species, owing to the sensitivity of vibrational modes to hydrogen bonding. The similar chemistry of water—water and water—peptide interactions requires that there be great accuracy in spectroscopic measurements of the hydration process. Since the review of the field by Kuntz and Kauz-mann (1974), the Fourier transform technique for IR and the tunable laser for Raman spectroscopy have offered important improvements in methodology. [Pg.107]


See other pages where Fourier transform methodology is mentioned: [Pg.84]    [Pg.49]    [Pg.66]    [Pg.256]    [Pg.73]    [Pg.509]    [Pg.517]    [Pg.528]    [Pg.151]    [Pg.115]    [Pg.561]    [Pg.84]    [Pg.49]    [Pg.66]    [Pg.256]    [Pg.73]    [Pg.509]    [Pg.517]    [Pg.528]    [Pg.151]    [Pg.115]    [Pg.561]    [Pg.628]    [Pg.289]    [Pg.304]    [Pg.392]    [Pg.418]    [Pg.474]    [Pg.291]    [Pg.88]    [Pg.95]    [Pg.92]    [Pg.115]    [Pg.152]    [Pg.39]    [Pg.628]    [Pg.359]    [Pg.540]    [Pg.181]    [Pg.184]    [Pg.258]    [Pg.29]    [Pg.242]    [Pg.283]   
See also in sourсe #XX -- [ Pg.49 ]




SEARCH



© 2024 chempedia.info