Water Fourier transform infrared spectroscopy

The SNIFTIRS approach. The acronym SNIFTIRS means Subtractively Normalized Interfacial Fourier Transform Infrared Spectroscopy. The basic concept of this method involves the fact that the raw data obtained directly from the Fourier Transform process contain components which are undesirable. Firstly, there is material in the solution which may have affected the spectrum. Secondly, unwanted information on certain material on the electrode (adsorbed water, for example) is best eliminated. 

Spectroscopic techniques may provide the least ambiguous methods for verification of actual sorption mechanisms. Zeltner et al. (Chapter 8) have applied FTIR (Fourier Transform Infrared) spectroscopy and microcalorimetric titrations in a study of the adsorption of salicylic acid by goethite these techniques provide new information on the structure of organic acid complexes formed at the goethite-water interface. Ambe et al. (Chapter 19) present the results of an emission Mossbauer spectroscopic study of sorbed Co(II) and Sb(V). Although Mossbauer spectroscopy can only be used for a few chemical elements, the technique provides detailed information about the molecular bonding of sorbed species and may be used to differentiate between adsorption and surface precipitation. 

Other applications of subcritical water extraction-solid-phase microextraction are the determination of terbuthylazine and its metabolites [123], polycyclic aromatic hydrocarbons [124,125] and polychlorobiphenyls [63]. Yang and Her [193] collected 1-chloronaphthylene, nitrobenzene and 2-chloro-toluene in soil on a hydrophobic polyisobutylene disc prior to analysis by attenuated total reflectance Fourier transform infrared spectroscopy. 

Combination of static subcritical water extraction and solid-phase microextraction Comparison of CHC1F2, N2O and CO2 extractants. CHC1 F2 gave highest recovery, methanol-modified CO2 gave 90% recovery Combination of supercritical fluid extraction with off-line Fourier transform infrared spectroscopy... 

In THE PAST DECADE, IMPROVEMENTS IN infrared spectroscopic instrumentation have contributed to significant advances in the traditional analytical applications of the technique. Progress in the application of Fourier transform infrared spectroscopy to physiochemical studies of colloidal assemblies and interfaces has been more uneven, however. While much Fourier transform infrared spectroscopic work has been generated about the structure of lipid bilayers and vesicles, considerably less is available on the subjects of micelles, liquid crystals, or other structures adopted by synthetic surfactants in water. In the area of interfacial chemistry, much of the infrared spectroscopic work, both on the adsorption of polymers or proteins and on the adsorption of surfactants forming so called "self-assembled" mono- and multilayers, has transpired only in the last five years or so. 

Characterization. The PPNVP and PPNVP/PEUU films were characterized by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), electron spectroscopy for chemical analysis (ESCA), ellipsometry, and water contact angles in air. Two independent methods, a modification of the radioimmunoassay used by Ziats, et. al. (14) and an immunochemical stain based on the ABC immunohistochemical staining method (15) were developed to assay the binding of GOx to the PPNVP/PEUU support. 

K.E. Goeringer and M.W. Ellzy, Analysis of alkylphosphonic acids in environmental waters by gas chromatography/ion trap mass spectrometry and gas chromatography/matrix isolated Fourier transform infrared spectroscopy, in Proc. 1994 ERDEC Sci. Conf. Chem. Biol. Def. Res., D.A. Berg (Ed.), National Technical Information Service, Springfield, 149-155 1996. 

Surface modification of polyvinyl chloride films, both plasticised and unplasticised, using amino thiophenol in dimethyl formamide and water mixtures, was examined using attenuated total reflection fourier transform infrared spectroscopy, Raman spectroscopy and nuclear magnetic resonance spectroscopy. Reaction kinetics, and the amount of dioctyl phthalate plasticiser leached out during the reaction were determined. Surface selectivity and degree of modification was found to depend on reaction time. 19 refs. 

Surface analysis is a big challenge for the modihed polymers. It is well known that hydrophilicity and hydrophobicity can be measured in terms of water adhesion tension (x°). x° greater than 30 dyne cm are designated as hydrophilic and x° less than 30 dyne cm are designated as hydrophobic (Ma et al., 2007). Attenuated total reflec-tance-Fourier transformed infrared spectroscopy (ATR-FTIR) and XPS are two widely used techniques for the analysis of surfaces of modihed polymers. ATR-FTIR is not very specihc to the polymer surfaces as the signals are a combination of surfaces and underneath. Therefore, XPS can be used for the surface analysis because this technique has much smaller sampling depth (typically, <10 nm) (Ma et al., 2007). 

Jamtveit et al. (2001) measured water contents in olivines from basalts and picrites from the North Atlantic Volcanic Province using Fourier-transform infrared spectroscopy (FTIR). They found H2O contents from <0.5 ppm to —18 ppm, and suggested that oh vines with... 

Holmen B. A., Tejedor-Tejedor M. I., and Casey W. H. (1997) Hydroxamate complexes in solution and at the goethite-water interface a cylindrical internal reflection Fourier transform infrared spectroscopy study. Langmuir 13, 2197-2206. 

Surface analytical techniques. A variety of spectroscopic methods have been used to characterize the nature of adsorbed species at the solid-water interface in natural and experimental systems (Brown et al, 1999). Surface spectroscopy techniques such as extended X-ray absorption fine structure spectroscopy (EXAFS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) have been used to characterize complexes of fission products, thorium, uranium, plutonium, and uranium sorbed onto silicates, goethite, clays, and microbes (Chisholm-Brause et al, 1992, 1994 Dent et al, 1992 Combes et al, 1992 Bargar et al, 2000 Brown and Sturchio, 2002). A recent overview of the theory and applications of synchrotron radiation to the analysis of the surfaces of soils, amorphous materials, rocks, and organic matter in low-temperature geochemistry and environmental science can be found in Fenter et al (2002). 

The secondary structure of proteins may also be assessed using vibrational spectroscopy, fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy both provide information on the secondary structure of proteins. The bulk of the literature using vibrational spectroscopy to study protein structure has involved the use of FTIR. Water produces vibrational bands that interfere with the bands associated with proteins. For this reason, most of the FTIR literature focuses on the use of this technique to assess structure in the solid state or in the presence of non-aqueous environments. Recently, differential FTIR has been used in which a water background is subtracted from the FTIR spectrum. This workaround is limited to solutions containing relatively high protein concentrations. 

The most useful spectral methods for the characterization of water in solids are Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), and powder X-ray diffraction (XRD). A thorough treatment of these methods is not given here instead the example of ampicillin presented by Brittan, et sdP is summarized. 

Fourier-transform infrared spectroscopy (FTIR) and pH measurements are the techniques most often adapted for in-line IPC. pH measurements are used for reactions that are run in water or have an aqueous component, e.g., an aqueous extraction. FTIR is especially good for monitoring continuous reactions [12] and reactions that would be dramatically changed by exposure to the atmosphere and temperature of the laboratory. Suitable reactions include low-temperature reactions, reactions run under pressure, reactions with gaseous or toxic materials (e.g., ethylene oxide), and reactions run under inert atmosphere. Further advantages of in-line assays are that no samples need to be prepared, and assay results can be generated within minutes. 

MacCarthy, P., Mark, H. B., Jr., and Griffiths, P. R. (1975). Direct measurement of the infrared spectra of humic substances in water by Fourier transform infrared spectroscopy. J. Agric. Food Chem. 23, 600-602. 

The work described in the present paper concerns the Influence of water and organic solvents on the ionic interactions in lightly sulfonated polystyrene (SFS) ionomers. The focus will be specifically directed towards the Influence of the solvent environment on the cation-anion and cation-cation interactions. Fourier transform Infrared spectroscopy (FTIR) was used to probe the former while electron spin resonance spectroscopy (ESR) was used to study the latter. Experiments were carried out with dissolved, swollen, and bulk ionomers. 

Gonzalez-Bianco, C., Rodriguez, L.J. and Velazquez, M.M. (1997) Effect on the addition of water-soluble polymers on the structure of aerosol OT water-in-oil microemulsions A Fourier transform infrared spectroscopy study. Langmuir, 13, 1938-1945. 

Griffiths PR, de Haseth JA (2007) Fourier Transform Infrared Spectroscopy. Wiley, Hoboken Gunzler H, Gremlich HU (2002) IR Spectroscopy. Wiley-VCH, Weinheim Guo Y, Peng Y, Wu P (2008) A two-dimensional correlation ATR-FTIR study of poly(vinyl methyl ether) water solution. J Molec Stmcture 87 486-492 Hermans JJ (1947) Deformation and swelling of polymer networks containing comparatively long chains. Trans Faraday Soc 43 591-600... 

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