Infrared spectroscopy attenuated total reflectance Fourier

Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy. Attenuated total reflectance (atr) ftir spectroscopy is based on the principle of total internal reflection (40). Methods based on internal reflection in the uv and visible regions of the spectrum are also common in addition to those in the ir region. The implementation of internal reflection in the ir region of the spectrum provides a means of obtaining ir spectra of surfaces or interfaces, thus providing molecularly-specific vibrational information. 

FTIR-ATR Fourier transform infrared spectroscopy-attenuated total reflection method... 

ATR-FTIR spectroscopy (attenuated total reflectance Fourier transform infrared spectroscopy)—IR spectroscopy uses the absorption of infrared radiation to probe the vibrational frequency of molecular motions. Attenuated total reflectance method uses a crystal of high refractive index to channel the infrared light (using total internal reflectance) into the crystal and causes only a thin layer of a sample in contact with the exterior of the crystal to be sensitively detected. 

Spectroscopic methods are mainly useful to identify the elements, functional groups, and chemical structures close to the biomaterial surface. Techniques like X-ray photoelectron spectroscopy, attenuated total reflection fourier transform infrared spectroscopy, and secondary ion mass spectrometry have been used widely in determining the elemental composition and charged species at biomaterial surface. Other important characteristics obtained from the biomaterial surface are surface energy and relative wettability using thermodynamic method such as contact angle experiments. 

Increasing lA concentration in copol5mierization results in lower viscosities (Fig. 1.14). lA content of copol5miers was determined using Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and nuclear magnetic resonance (NMR) spectroscopies. The absoption bands at 1628 and 1730 cm due to C=0 stretching vibrations in carboxylic acid showed an increase... 

Infrared spectroscopy, including Fourier-transform infrared (FTIR) spectroscopy, is one of the oldest and most widely used analytical techniques in adhesion-related research. Transmission infrared spectroscopy has been used to identify compounds used in formulating adhesives and to follow curing reactions. Attenuated total reflection (ATR) (see Infrared spectroscopy attenuated total reflection) has been used to probe the surface composition of polymers that have been surface modified by an etching process or by deposition of a film. More recently, reflection-absorption infrared spectroscopy (see Infrared spectroscopy RAIR) has been used to characterize thin films on the surfaces of reflecting substrates. 

The chemical structure of the membrane can be analyzed with spectroscopic methods, of which the Fourier transform infrared spectroscopy attenuated total reflectance (FTIR-ATR) method is the most utilized. However, Raman spectroscopy and IR spectroscopy complement each other, and, thus, if both methods arc used, the information obtained on the membrane chemical structure is quite comprehensive. If only information from the membrane skin layer is needed, the most surface-sensitive methods—X-ray photoelectron spectroscopy (XPS) and lime-of-flight secondary ion mass spectroscopy (TOF-SIMS)— have to be used. 

Silicone elastomers are covalently crosslinked networks with an effective infinite molecular weight and are, as such, insoluble and intractable. Consequently the interrogative spectroscopic and imaging methodologies that may be employed to probe such a network structure are almost wholly confined to the solid state. Surface vibrational spectroscopies attenuation total reflectance Fourier transform infrared (ATR-FTIR) and resonance Raman spectroscopy... 

Attenuated total reflectance Fourier transform infrared spectroscopy,... 

Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), 24 111-114 Attenuation, 77 132-133 Attenuation length (AL), 24 87-89 Attrition, catalyst deactivation mechanism, 5 256t... 

Gaboury, S. R. Urban, M. W. Analysis of Gas-Plasma-Modified Poly(Dimethylsiloxane) Elastomer Surfaces. Attenuated-Total-Reflectance-Fourier Transform Infrared Spectroscopy. In Structure-Property Relations in Polymers Urban, M. W., Graver, C. D., Eds. Advances in Chemistry Series 236 American Chemical Society Washington, DC, 1993 pp 777-790. 

Principal Component Regression (PCR) was used by Tuchbreiter and MueUiaupt to determine the composition of a number of random ethane/propene, ethane/1-hexene, and ethane/l-octene copolymers [120]. After polymerization, the polymers were characterized by both Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FT-IR) and C NMR and multivariate calibration models using PCR were subsequently developed to estimate the co-monomer content. 

Tuchbreiter A, Marquardt J, Zimmermann J et al. (2001) High-throughput evaluation of olefin copolymer composition by means of attenuated total reflection fourier transform infrared spectroscopy. J Comb Chem 3 598-603... 

Aspartic peptidases, 365 Atmospheric pressure chemical ionization (APCI), used with LC/MS ATR-FTIR. see Attenuated total reflection Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), trans fatty acids, 505-511 Autoxidation. see also Oxidation discussed, 535 of lipids, 558, 627 prevention of, 558... 

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. 

Yang and Her [ 193] have described a rapid method for the determination of down to 200 ppt of semi-volatile compounds such as 1-chloronaphthalene, nitrobenzene and 2-chlorotoluene in soils by coupling solid-phase microextraction with attenuated total reflectance Fourier transform infrared spectroscopy. 

To shed light on the mechanism of formation of silsesquioxane a7b3, to identify the species formed during the process, and to try to explain the high selectivity towards structure a7b3 of the optimised synthetic method described above (64% yield in 18 h), the synthesis of cyclopentyl silsesquioxane a7b3 was monitored by electrospray ionisation mass spectrometry (ESI MS) [50-52] and in situ attenuated total reflection Fourier-transform infrared (ATR FTIR) spectroscopy [53, 54]. Spectroscopic data from the latter were analysed using chemometric methods to identify the pure component spectra and relative concentration profiles. 

Regarding the spatial aspects of the enzymatic degradation of CA-g-PLLA, a surface characterization [30] was carried out for melt-molded films by atomic force microscopy (AFM) and attenuated total-reflection Fourier-transform infrared spectroscopy (ATR-FTIR) before and after the hydrolysis test with proteinase K. As exemplified in Fig. 3 for a copolymer of MS = 22, the AFM study showed that hydrolysis for a few weeks caused a transformation of the original smooth surface of the test specimen (Fig. 3a) into a more undulated surface with a number of protuberances of 50-300 nm in height and less than a few micrometers in width (Fig. 3b). The ATR-FTIR measurements proved a selective release of lactyl units in the surface region of the hydrolyzed films, and the absorption intensity data monitored as a function of time was explicable in accordance with the AFM result. 

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. 

Brancaleon, L., Bamberg, M.P., Sakamaki, T., and Kollias, N. Attenuated total reflection-Fourier transform infrared spectroscopy as a possible method to investigate biophysical parameters of stratum corneum in vivo. J. Invest Dermatol. 2001 116 380-386. 

ATR-FTIR Attenuated Total Reflection Fourier Transform Infrared Spectroscopy... 

In this section we discuss a method of controlled material degradation for individual organic semiconductors and also for the blends used in bulk heterojunction solar cells [37]. The degradation is studied using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and by determining current/voltage characteristics (I/V measurements) of the devices. 

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... 

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. 

Kubicki, J.D. et al., Attenuated total reflectance Fourier-transform infrared spectroscopy of carboxylic acids adsorbed onto mineral surfaces, Geochim. Cosmochim. Acta, 63, 2709, 1999. 

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