ToF SIMS spectra

Fig. 3.10. Positive TOF SIMS spectra from the defective area and from a spot remote from the defect [3.19].

Fig. 44. Positive TOF-SIMS spectra of plasma polymerized acetylene film after reaction with a model rubber compound for (A) 0 and (B) 15 min. Positive TOF-SIMS spectra of plasma polymerized acetylene film after reaction with a model rubber compound for (C) 35 and (D) 65 min. Reproduced by permission of Gordon and Breach Science Publishers from Ref. [56].

Fragments and masses observed in positive TOF-SIMS spectra of PMDA/ODA polyimide (reproduced by permission of John Wiley and Sons from Ref. [33])... 

TOF-SIMS spectra supported the suggestion that eopper interacted with untreated polyimide through the imide earbonyl group as shown in Fig. 27. Numer-... 

After metallization of the plasma-modified polyimide, there were a number of peaks in the TOF-SIMS spectra that confirmed the existence of Cu-N bonds as required by the proposed reaction mechanism (see Fig. 28). The most significant... 

The apparatus for the PFAM film coating on the slider surface is shown in Fig. 1 (a). The film thickness was measured by the TOF-SIMS as shown in Fig. 1 (b). It used a pulsed primary Ga+ ion beam to impact the surface of the PFAM film with an inset energy of 15 keV, an extractor current of 2 fj,A, beam current of 600 pA, a pulse width of 17.5 ns, and a frequency of 10 kHz, respectively. The positive TOF-SIMS spectra on the slider surface is shown in Fig. 2 where the peaks at m/z 31, 50, 69, 100, and 131 in Fig. 2(a) correspond to the positive secondary ion fragments of CF+, CFj, C2F4, and C3F5, respectively. The peak at m/z 469 apparent in Fig. 2(b) corresponds to the ion C12H7F 15O2H+ which is the characteristic ion of PFAM molecules. Therefore, the positive TOF-SIMS spectra demonstrates the existence of PFAM film [24,25]. The thickness of the PFAM film can be determined... 

Fig. 2— Positions of the positive TOF-SIMS spectra of PFAM thin film on slider, showing the most characteristic fragments (a) positive, m/z=0-150 (b) positive, m/z=460-475.

For a ToF-SIMS investigation of the surface oxidative degradation of low-density polyethylene (LDPE), the polymer was exposed to 1802 rather than 1602 in order to be able to readily discriminate oxygen introduced by the ageing process from that in the polymer prior to ageing [102], Figure 36 shows an example series of ToF-SIMS spectra from this investigation, which shows the clear separation of the lsO species from the lsO species. In the study, close correlation was observed between the intensity of the lsO carbonyl species determined by mid-infrared spectroscopy with the ToF-SIMS 180- peak intensity as a function of 1802 exposure time. ToF-SIMS spectra obtained from microtomed cross-sections showed no... 

Figure 3. Positive TOF-SIMS spectra of various mineral components silylated with CH3Si(OC2H5)3.

In agreement with the NMR results, the bulky alkyl-alkoxysilanes RSi(OC2H5>3 (R = i-C4H9 and n-CgH ) are not able to form polymeric or spherical siloxanes under the conditions used for this study. The observed TOF-SIMS spectra are similar to the El spectra of the pure liquids and, therefore, underline the presence of physically adsorbed species [5,9]. 

Figure 15.4 Positive ion ToF SIMS spectra of five fluorinated compounds. Reproduced from Applied Surface Science, Torrisi et al., Copyright 2008 Elsevier...

A similar study has been performed on silk [Howell et al. 2007]. The ToF-SIMS fingerprint of silk exhibits the presence of different amino acid fragments (positive ion mode). In contrast to wool, the effect of artificial ageing is not obvious and no modification appears in the ToF-SIMS spectra. Nevertheless, the study of the cleaning procedures leads to the same conclusion as that in the case of wool. The amount of remaining surfactant increases with artificial ageing. 

ToF-SIMS spectra were acquired in positive ion mode and four different extractives were identified. The two main peaks were assigned to hinokinin (m/z 353) and hinokir-esinol (m/z 252). Lower peaks at m/z 299 and m/z 302 were assigned to hinokione and hinokiol, respectively. These identifications were confirmed by the study of the pure molecules. 

Figure 15.10 (a) Positive ion and (b) negative ion ToF SIMS spectra from a pellet of verdigris. With kind permission from Springer Science and Business Media, Analytical and Bioanalytical Chemistry, 383, 991 997, Van Ham, Copyright 2005... 

Figure 15.12 Identification of blood, (a) ToF SIMS spectra in positive ion mode of hemin and haemoglobin, (b) ToF SIMS spectra in positive ion mode of two cross sections of boliw patina (samples B1 and B3) and images of the localization of haem and proteins in the sample (see colour...

O. D. Sanni, M. S. Wagner, D. G. Briggs, D. G. Castner and J. C. Vickerman, Classification of adsorbed protein static ToF SIMS spectra by principal component analysis and neural networks, Surface and Interface Analysis, 33, 715 728 (2002). 

Functionalities on the silica surface - The ToF-SIMS spectra were recorded of the untreated and treated silicas. Figure 8 represents an untreated silica sample, and Fig. 9 an acetylene-treated one. They show a complex structure of a plasma-polymerized acetylene film on the silica surface. 

Fig. 8 ToF-SIMS spectra of untreated silica (a) positive and (b) negative...

Wagner et al. [108] developed a PLS model to predict the amount of protein adsorbed in a metallic basis using time-of-flight SIMS (TOF-SIMS) spectra. Study of the multivariate models yielded insight into the surface chemistry and the mechanism for protein resistance of the coatings. The same group reported two other similar studies with satisfactory results [109,110]. 

Figure 3. The positive ion TOF SIMS spectra for the deionized water-washed E-glass slides after heat cleaning at 250°C.

Figure 8. The negative ion TOF SIMS spectra for the HAPS-coated E-glass slides. See text for definitions.

FIG. 7 Positive ion ToF-SIMS spectra of methyl methaerylate-poly(ethylene glycol) methacrylate copolymers with average PEG molecular weights of I(XX). (From Ref. 33.)... 

Secondly, the TOF-SIMS spectra show distinct differences in the fragmentation behavior of the higher T OH molecules ( > 7) (Fig. 5). In case of the methyl derivatives, the contribution of the fragment ion [T OH-OH]" increases with the number of repeating units in the molecule, whereas for ethyl, -propyl, and /-butyl species the loss of the alkyl group is favored. This furthermore suggests the presence of isomeric T OH siloxanes. 

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