Surface atomic concentrations

The Fe-B nanocomposite was synthesized by the so-called pillaring technique using layered bentonite clay as the starting material. The detailed procedures were described in our previous study [4]. X-ray diffraction (XRD) analysis revealed that the Fe-B nanocomposite mainly consists of Fc203 (hematite) and Si02 (quartz). The bulk Fe concentration of the Fe-B nanocomposite measured by a JOEL X-ray Reflective Fluorescence spectrometer (Model JSX 3201Z) is 31.8%. The Fe surface atomic concentration of Fe-B nanocomposite determined by an X-ray photoelectron spectrometer (Model PHI5600) is 12.25 (at%). The BET specific surface area is 280 m /g. The particle size determined by a transmission electron microscope (JOEL 2010) is from 20 to 200 nm. 

When the peak intensity ratio Ij/lj is measured for each of all the elements observed (carbon, oxygen, chromium and nickel), the surface atomic concentration ratio nj/nj of the elements can be given by the following equation, if surface contamination is negligible ... 

Relative surface atomic concentrations (in %) of the elements present at the three resolved angles for the uncoated E glass slide... 

Fig. 12.2. The surface atom concentration ratio [Ce] to ([Ce] + [M]), in which M is either Al, Zn, or Fe, as a function of thickness of cerium oxide film, both determined by AES profiling, for alloys immersed in solution for the number of days indicated (from R.B.W. Hinton in Reviews on Corrosion Inhibitor Science and Technology (1993), edited by A. Raman and P. Labine, 1-10-1. Copyright by NACE International. All rights reserved by...

The formation of a rare earth metal oxide on the metal surface, impedes the cathodic reduction of oxygen and thus cathodic inhibition is achieved by the addition of a rare earth metal salt to a system. The surface atom concentration ratio, [Ce/Ce + M], where M is Fe, Al or Zn, is a function of cerium oxide film thickness determined by AES depth profiles as shown in Fig. 12.2. 

Table 4 Quantified surface atomic concentrations determined by XPS...

Surface Atomic Concentrations for Paper Specimens All specimens 50/50 hardwood/softwood except as noted... 

XPS measurements were carried out on an AXIS NOVA photoelectron spectrometer (Kratos Analytical, Manchester, UK). The surface atomic concentration was determined firom peak areas using sensitivity factors. Spectrum background was subtracted according to Shirley. The XPS peaks of the Ti species were analyzed by spectra deconvolution software (CasaXPS-Vision 2, Kratos Analytical, UK). 

Table 2. Surface Atomic concentration of some chromospheres of different pigments in oil paint layers...

Table 4. Average surface atomic concentration of David s marble fragments...

The average surface atomic concentration of the elements acquired in different areas of the two fragments are reported in Table 4... 

Table n. Surface Atomic Concentrations of Mixed Hydrogels of HEMA and 1 or 2 (40 wt%) as Measured by X-ray Pliotoelectron Spectroscopy (XPS)°... 

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