Spectroscopy and XPS

Because of the relatively high loading of functional groups on these hyperbranched PE powders, it was feasible to characterize the products and intermediates in this catalysts synthesis by P CP-MAS NMR spectroscopy, ATR-IR spectroscopy, and XPS analysis. P CP-MAS NMR spectroscopy was especially useful for in distinguishing the phosphinated powder, phosphine-palladium complex, and any adventitiously formed phosphine oxide. Similar NMR analyses were not successfully carried out on hyperbranched grafts on PE films. However, when this same phosphine ligand synthesis and introduction of Pd was carried out on a PE film sample, it was possible to analyze... 

The vanadium-containing materials have been characterised further by XRD, TPR, laser Raman spectroscopy and XPS in combination with Ar -sputtering. The influence of various catalyst pretreatments on the catalytic performance has also been investigated. 

Bhowmick and co-workers [168] investigated the bulk and surface modification of ethylene propylene diene monomer (EPDM) rubber and fluoro-elastomer by electron beam irradiation. The structure of the modified elastomers was analysed with the help of IR spectroscopy and XPS. The gel content, surface energy, friction coefficient and dynamic mechanical properties of bulk modified fluoro-elastomers and the surface-modified EPDMs were also measured. The resultant properties of the modified EPDM were correlated with the structural alterations. 

Scheme 1.21 Schematic representation of the cyclopropanation of SWCNTs and the introduction of chemical markers for AFM visualization and 19F NMR spectroscopy and XPS (i) diethyl bromomalonate, DBU, room...

Gold colloids were observed both on the sides and at the ends of the nanotubes, indicating sidewall and termini modification. To confirm further the derivatiza-tion of the SWNTs, a perfluorinated marker was introduced by transesterification to allow the nanotubes to be probed by 19F NMR spectroscopy and XPS [160],... 

The CNTs, both single-walled nanotubes (SWNT) and multi-walled nanotubes (MWNT) prepared by chemical vapor deposition (CVD) and arc-discharge (AD) methods, respectively, were purchased from Iljin Nanotech, Co., Korea. For proton and electron irradiation experiments, CNTs sheets were prepared as shown in Figure 2 by filtration of the CNT solution mixed in dimethylformamide through a cellulose membrane (pore size 0.45 pm). The thickness of the CNT sheets was approximately 0.5 mm, and they were 47 mm in diameter. After drying in a vacuum oven at 80 °C for 24 hours, CNT sheets (Figure 2) were obtained. These sheets were used in the radiation experiments, and were used for analysis such as SEM, Raman spectroscopy and XPS without any further treatment. For a dispersion test, a CNT powder was used instead of the CNT sheets. 

From examining the spectroscopic characteristics of diamond films, many insights into their structure may be obtained. Most of all the Raman spectroscopy, XRD and electron energy loss spectroscopy (EELS) provide valuable information. Other methods like IR-spectroscopy and XPS shed light on the surface structure. These techniques are supplemented by microscopy methods, for example, by AFM and STM, so altogether the morphology of the films surface can be studied in quite some detail. 

We report in this study the hydrothermal synthesis of Co-silicate of MFI structure in alkaline media. The samples were characterized by XRD, chemical analysis, thermal analysis, A1-NMR, diffuse reflectance UV-visible spectroscopy and XPS spectroscopy. 

TiCl4 immobilized on surface of PE modified by graft polymerization of vinylpyridine, acrylonitrile, methyl vinyl ketone, allyl alcohol, allylamine, allyl sulfide or acrylic acid, has been studied with IR spectroscopy and XPS I166J. Cluster aggregates of Ti(IV) fixed on the surface, were discovered. Their formation did not cause the reduction of Ti(IV). In binary catalytic systems of Ti(IV) on an organo-aluminum polymeric support, Ti(IV) was reduced to Ti(III), and Ti(II) appeared at 343 K. The high and stable activity of immobilized titanium compounds during ethylene polymerization was attributed to deceleration of Ti(IV) reduction processes. 

Similar to the isomer shifts in Mdssbauer spectroscopy, the results from photo-electron spectroscopy are sensitive to the local chemical environment of an atom. [88] However, whereas Mdssbauer spectroscopy reflects the initial electronic structure of the system under investigation, probes the state after elimination of an electron. [84] Furthermore, whereas the Mdssbauer isomer shift gives informations on the s electron density within the nuclear volume, XPS results describe the overall electronic charge denaty of an atom. As such, Moss-bauer spectroscopy and XPS compliment each other in an ideal manner. 

Very recently, Montero and co-workers (369) have reported the pronounced structure sensitivity of MgO-catalyzed glyceryl tributyrate transesterification. In this study, size-controlled MgO nanoparticles were prepared by thermal treatment of Mg(OH)(OCH3). Controlled calcination was employed to control surface structure and the basicity was determined by the application of Auger spectroscopy and XPS. Figure 40 demonstrates the relationship between turnover frequency and snrface polarizability (which reflects surface basicity). It was found... 

For knowledge of the exact composition of an alloy used as coating substrate or of the coating composition itself, more often elemental analyses have to be performed. In this context XRD (x-ray diffraction), EDX (energy-dispersive x-ray spectroscopy) and XPS (x-ray photoelectron spectroscopy) are to be named. 

The experimental papers cover the various spectroscopic techniques and a few deal with special materials. The introductory chapter (62) by Baer and Schneider presents an overview of this field and helps tie the various aspects together that are reviewed in detail in the remaining chapters of the volume. Photoemission studies (UPS - ultraviolet photoemission spectroscopy, and XPS - X-ray photoemission spectroscopy) on various materials are discussed by Campagna and Hillebrecht (chapter 63)- intermetallic compounds, by Lynch and Weaver (chapter 66)— cerium and its compounds, and by Hiifner (chapter 67) - chalcogenides. Other experimental techniques covered include BIS (bremsstrahlung isochromat spectroscopy) by Hillebrecht and Campagna (chapter 70), X-ray absorption and X-ray emission by Rohler (chapter 71) and inelastic electron scattering by Netzer and Matthew (chapter 72). 

Cyclohexylamine, pyridine, and triethyl-amine were studied on mild steel in 0.5 M H2SO4 by electrochemical impedance spectroscopy and XPS. Comparison of N (Is) spectra between active and passive regions showed that adsorption is significant only in the passive region. Two chemically distinct adsorbed amine species were detected in the experiment. The nature of the metal surface can be determinative of the performance of the inhibitors. 

The effects of lithium bis(oxalato) borate on the electrolyte oxidative decomposition, the surface chemistry of separators and the cathodes cycled in electrolytes with and without a lithium bis(oxala-to) borate additive were assessed using ATR-FTIR spectroscopy and XPS (57). 

Surface studies by Fourier transform infrared (FTIR) spectroscopy and XPS proved that there is no surface film formation on the electrodes (or Mg deposits) in ether-Grignard reagent solutions [32,46]. It is clear that Mg deposition takes place only on bare non-passivated surfaces. In general, the RMgX species in ethereal solutions undergoes the following equilibria [47] ... 

With technical samples, high-resolution STM, as it is the case for thiols on gold, is not applicable to obtain information about the molecular order. Other methods such as Fourier transform infrared (FTTR) spectroscopy and XPS have to be applied. 

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