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Infrared spectroscopy ATR

Heinen M, Jusys Z, Behm RJ. 2009. Reaction pathways analysis and reaction intermediate detection via simultaneous differential electrochemical mass spectrometry (DBMS) and attenuated total reflection Bourier transform infrared spectroscopy (ATR-BTIRS). In Vielstich W, Gasteiger HA, Yokokawa H, eds. Handbook of Buel Cells. Volume 5 Advances in Electrocatalysis. Chichester John Wiley Sons, Ltd., in press. [Pg.457]

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... [Pg.78]

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. [Pg.132]

Many important heterogeneous catalytic reactions occur at the interface between a solid catalyst and liquid or liquid-gas reactants. Notwithstanding the importance of solid-catalyzed reactions in the presence of liquid reactants, relatively little attention has been paid to spectroscopic methods that allow researchers to follow the processes occurring at the solid-liquid interface during reaction. This lack can be explained in part by the fact that there are only a few techniques that give access to information about solid-liquid interfaces, the most prominent of them being attenuated total reflection infrared spectroscopy (ATR-IR) and X-ray absorption fine structure (XAFS) spectroscopy. [Pg.228]

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... [Pg.757]

The primary techniques used in this study include X-ray photoelectron spectroscopy (XPS), reflection-absorption infrared spectroscopy (RAIR), and attenuated total reflectance infrared spectroscopy (ATR). XPS is the most surface-sensitive technique of the three. It provides quantitative information about the elemental composition of near-surface regions (< ca. 50 A sampling depth), but gives the least specific information about chemical structure. RAIR is restricted to the study of thin films on reflective substrates and is ideal for film thicknesses of the order of a few tens of angstroms. As a vibrational spectroscopy, it provides the type of structure-specific information that is difficult to obtain from XPS. The... [Pg.494]

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. [Pg.106]

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. [Pg.93]

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. [Pg.237]

The two additives have heen identified hy matrix assisted laser desorption ionisation mass spectrometry (MALDI-MS) and attenuated total reflection infrared spectroscopy (ATR). [Pg.186]

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). [Pg.102]

This work was supported by a grant from the National Science Foundation, t Abbreviations used are as follows. FTIR Fourier transform infrared spectroscopy, ATR attenuated total reflectance, IRE internal reflection element, SATR solution ATR FTIR, FSD Fourier self-deconvolution, PLS partial least-squares analysis, PRESS prediction residual sum of squares from PLS. SECV standard error of calibration values from PLS, PLSl PLS analysis in which each component is predicted independently, PLS2 PLS analysis in which all components are predicted simultaneously. [Pg.475]

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). [Pg.4760]

Critical surface tension and attenuated total reflectance infrared spectroscopy (ATR) of irradiated and unirradiated solution-cast PNF films was done in conjunction with R. Baier (9). [Pg.181]

The state of water in a membrane can become important for RO membranes as it is often related to rejection. Murphy and dePinho (1995) studied the state of water in RO and UF membrane active layers using attenuated total reflection fourier transform infrared spectroscopy (ATR-FTIR). Water content increased with porosity, and the strucmre of the water was dependent on average pore size. Large clusters of water were linked to low salt rejection, whereas low association of water in clusters indicated a low permeability to salt. [Pg.77]

Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR)... [Pg.348]

Platinum and palladium are effective catalysts for alcohol oxidation when used alone however, significant stability and selectivity improvements have been observed on incorporation of a second (usually less active) metal promoter such as Bi, Pb, and Sn [63-65]. These observations are common to aerobic selox of allyhc and benzylic alcohols, as well as polyols such as propylene glycol [64] and glycerol [66]. In the case of Bi, in situ X-ray absorption spectroscopy (XAS) and attenuated total reflection infrared spectroscopy (ATR-IR) indicate that the promoter protects Pt against deactivation by overoxidation and prevents site blocking by, for example, aromatic solvents [67]. [Pg.15]

The present chapter gives an overview of the ap>plication of Attenuated total reflection -Infrared spectroscopy (ATR-IR) to the environmentally important mineral - aqueous electrolyte interface. At these interfaces the important adsorption processes occur that limit the availability of potentially toxic solutes. These retention processes may retard for example the migration of solutes in aquifer systems or even immobilize them on the aquifer material, which is usually a natural mineral. Selected solutes may also via a preliminary adsorption process, which weakens bonds, enhance both dissolution kinetics and the equilibrium solubihty of a given mineral. [Pg.97]

San Francisco, Ca. 3rd-6th Nov.1996, p.521-33. 6A1 ATTENUATED TOTAL REFLECTION FOURIER TRANSFORM INFRARED SPECTROSCOPY (ATR FTIR) USEFUL TOOL FOR MOLECULAR ANALYSIS OF ADHESIVES, SEALANTS AND COATINGS Ishida H... [Pg.89]


See other pages where Infrared spectroscopy ATR is mentioned: [Pg.405]    [Pg.55]    [Pg.176]    [Pg.10]    [Pg.452]    [Pg.132]    [Pg.203]    [Pg.296]    [Pg.390]    [Pg.1829]    [Pg.1596]    [Pg.321]    [Pg.1371]    [Pg.294]    [Pg.60]    [Pg.65]    [Pg.636]    [Pg.165]    [Pg.340]    [Pg.216]    [Pg.169]    [Pg.138]   
See also in sourсe #XX -- [ Pg.109 , Pg.164 , Pg.293 ]




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ATR

ATR spectroscopy

Atred

Attenuated Total Infrared Internal Reflectance (ATR) Spectroscopy (Spectra-Tech)

Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR

Fourier transform infrared spectroscopy ATR-FTIR)

Infrared and IR-ATR spectroscopy

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