Analysis by X-ray photoelectron spectroscopy

Hammer, G.E. and Drzal, L.T. (1980). Graphite fiber surface analysis by X-ray photoelectron spectroscopy and polar/dispersive free energy analysis. Application of Surf. Sci.. 4, 340-355. 

Cox, X. B., and R. W. Linton, Particle Analysis by X-Ray Photoelectron Spectroscopy, in Physical and Chemical Characterization of Individual Airborne Particles (K. R. Spurny, Ed.), Chap. 18, pp. 341-357, Ellis Horwood, Chichester, 1986. 

By anodic treatment in acidic solution, p-Cdg Zno g5Te becomes porous. Coulometry and chemical analysis by X-ray photoelectron spectroscopy indicate that the pore walls are covered by a more or less homogeneous layer of elemental tellurium. A passivating effect of this layer could explain why anodic etching of the p-type material yields a porous morphology, and the layer could also be responsible for changes observed in the photoelectrochemical properties. 

W.M. Riggs and M.J. Parker. Surface Analysis by X-Ray Photoelectron Spectroscopy. In A.W. Czan-dema, editor. Methods of Surface Analysis. Methods and Phenomena Their Applications in Science and Technology, Volume 1. Elsevier, New York, 1975. 

To understand the influence of allo5dng elements on the passivity of stainless steels, researchers have combined electrochemical and siufece analysis. Polarization diagrams provide the first indication of the overall influence of alloy additions on the active-passive transition, passivity, and pitting resistance. However, siuface analysis by X-ray photoelectron spectroscopy (XPS) of prepassivated siufaces provides a direct observation of the location and the chemical state of an alloying element. Such... 

Surface characterization studies by X-ray photoelectron spectroscopy (XPS) were conducted using DuPont 650 and Perkin Elmer 5300 instruments. Samples were prepared by placing solid material on double stick adhesive tape, or by allowing solvent to evaporate from an acetone dispersion of a suspension placed on a stainless steel probe. A magnesium anode was used as the X-ray source (hv 1253.6 eV). The temperature of samples during the analysis was approximately 30-40°C and the vacuum in the analysis chamber was about 10 torr. Potential... 

A Sulfur K Edge X-ray Absorption Near Edge Structure (XANES) Spectroscopy method has been developed for the direct determination and quantification of the forms of organically bound sulfur in nonvolatile petroleum and coal samples. XANES spectra were taken of a number of model compounds, mixtures of model compounds, heavy petroleum and coal samples. Analysis of the third derivatives of these spectra allowed approximate quantification of the sulfidic and thiophenic components of the model mixtures and of heavy petroleum and coal samples. These results are compared with those obtained by X-ray Photoelectron Spectroscopy (XPS). 

A recent paper by Lairdinvestigated the efficacy of HPAM flocculation of kaolinite, illite and quartz by carrying out visible absorption experiments. He concluded that HPAM more effectively flocculates kaolinite than quartz or illite. This was also the conclusion of previous work by Allen et al. who studied the adsorption of HPAM onto kaolinite, quartz and feldspar at various HPAM concentrations and solution pH by X-ray photoelectron spectroscopy (XPS). Much of the previous work on polyacrylamide adsorption onto aluminosilicates monitored the adsorbed amount by viscometry, carbon analysis and radiotracer techniques. These methods rely on following adsorption by subtraction from that detected in solution. 

The thickness of the deposits was determined by the ball cratering method or SEM measurement of cross-sections. The elemental composition was determined by electron microprobe analysis with wavelength dispersive spectroscopy (EPMA-WDS) on a Camebax Cameca equipment and by X-ray photoelectron spectroscopy (XPS) on a VG Escalab MK2 apparatus... 

Main group element analysis was carried out with a Perkin-Elmer CHN elemental analyzer, while molybdenum analysis was performed using atomic absorption spectroscopy. The content of Mo and O on the surface of the catalysts was obtained by X-ray photoelectron spectroscopy (XPS) using a Shimazu ESCA-850 spectrometer with monochromatic MgKa. Since Mo 3p3/2 spectra overlapped with the N Is spectra for the nitrided catalysts, the degree of nitriding (N IsfMo 3d ratio) had to be obtained from a combination of elemental analysis and XPS. 

Surface Analysis of Fibers and Polymers by X-Ray Photoelectron Spectroscopy Industrial Applications... 

The chemical composition can be measured by traditional wet and instrumental methods of analysis. Physical surface area is measured using the N2 adsorption method at liquid nitrogen temperature (BET method). Pore size is measured by Hg porosimetry for pores with diameters larger than about 3.0 nm (30 A) or for smaller pores by N2 adsorp-tion/desorption. Active catalytic surface area is measured by selective chemisorption techniques or by x-ray diffraction (XRD) line broadening. The morphology of the carrier is viewed by electron microscopy or its crystal structure by XRD. The active component can also be measured by XRD but there are certain limitations once its particle size is smaller than about 3.5 nm (35 A). For small crystallites transmission electron microscopy (TEM) is most often used. The location of active components or poisons within the catalyst is determined by electron microprobe. Surface contamination is observed directly by x-ray photoelectron spectroscopy (XPS). 

Low tenperature isotropic (LTI) pyrolytic carbon has been studied by X-ray photoelectron spectroscopy, scanning electron microscopy, and energy dispersive X-ray analysis. Both silicon-alloyed and unalloyed carbons were studied, in both as-deposited and polished (finished) forms. The polished materials contain significant amounts of surface oxygen. Approximately 1 in 10 of the carbon atoms in the surface volume analyzed by XPS are... 

The compositions of the products were determined by inductively coupled plasma (ICP) with a Perkin-Elmer plasma 40 emission spectrometer. Simultaneous differential thermal analysis and thermogravimetric (DTA-TG) curves were carried out by using Perkin-Elmer DTA-7000, TGA-7 PC series thermal analysis instrument in air with a heating rate of 10 °C /min. The infrared (IR) spectra were recorded on an Impact 410 IR spectrometer on samples pelletized with KBr powder. Valence states were determined by X-ray photoelectron spectroscopy (XPS). The XPS for powder samples fixed on double sided tapes was measured on an ESCA-LAB MKII X-ray photoelectron spectrometer. The Cis signal was used to correct the charge effects. 

Chemical analysis of the superficial regions of the samples was performed by X-ray photoelectron spectroscopy (XPS) with a Perkin-Elmer Phi 5300 ESCA, employing Mg Ka x-rays. Binding energies are referenced to the gold fy/2 transition at 83.8 eV (gold was sputtered onto a small spot of the sample prior to analysis). 

Copper-containing molecular sieve materials are very important catalysts in many liquid-phase oxidation reactions. The analysis of metal content is usually obtained using atomic absorption spectroscopy (AAS) but this provides no information on the distribution of the metal within the material. In this paper, we report on the characterisation of a siliceous MCM 41 material postmodified with a Schiff base copper complex by x-ray photoelectron spectroscopy (XPS), AAS and other standard techniques. Quantitative estimations of the copper concentrations and chemical states and its distribution within the material have been made using XPS. The effect of modification by the Schiflf base copper complex on the surface characteristics of the MCM 41 was investigated by nitrogen sorption at 77 K. 

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