Transition peak

The PIA spectra obtained show an electronic transition peaking at 0.26 eV (see Fig. 9-17) accompanied by infrared active vibrational modes which reveal the charged nature of the observed states [31]. The dependence of the PIA intensity on temperature is depicted in Figure 9-17. 

Recent NEXAFS (11,2A) have confirmed -the ethylldyne structure proposed by LEED analyses (1A,21) and further determined the structure of adsorbed molecular ethylene. Figure 4 shows the NEXAFS spectra for ethylldyne (a) and ethylene (b) on the Pt(lll) surface taken for two Incidence angles of the X-ray beam. The transitions observed In these NEXAFS spectra have been assigned using SCF-Xo calculations (24). For the ethylldyne spectrum taken at 20 Incidence angle peak A Is caused by a C(ls)+o j, transition peak B Is caused by a C(ls)+o (, (, transition. Peak A In the... 

Amino acid Electronic transitions Peak wavelengths (nm) Ap LACmax (M-1 cm-1)4... 

No significant difference is observed in the locus of failure data for the APS treated samples presented in Table 2. A closer look at the XPS high resolution scans as shown in Fig. 4 supports the interpretation that the failure is within the polyimide close to the PI-APS interface, but not at it. This is in particular verified by the presence of C=0 C(ls) peak at about 288.9 eV, ji-to-jr transition peak, and the N( 1 s) peak at 400.8 eV due to imide nitrogens. 

The N(ls) peak on the sapphire failure surfaces indicates presence of imide (peak at 400.7-401.0 eV), which suggests presence of polyimide on the sapphire failure surface. This is supported by the C(ls) data which show the presence of the carbonyl C(ls) species as well as jr-to-jr transition peak due to aromatic species. Since the polyimide failure surface shows only C(ls), N(ls), and O(ls) peaks in relative abundance, characteristic to the polyimide, it can be said that... 

The curves of the raw graft copolymer and of the poly(ethylene-g-vinyl chloride) are rather close to that of the low-density polyethylene. The outstanding fact is the absence of the PVC transition peak (between 60° and 100°C) in the mechanical loss curves of these two products. This means that they contain no rigid PVC phase in spite of the presence of about 25 weight % of ungrafted polyvinyl chloride in the raw graft copolymer. This PVC seems thus to be strongly compatibilized with the other constituents by the poly(ethylene-g-vinyl chloride). 

The appearance of a sharp central peak in the deuteron NMR spectrum for unaligned lyotropic liquid crystalline samples has been observed by several authors (30, 33, 34). This has been interpreted in terms of phase inhomogenities (35) or isotropic motion (36). However, recently Wennerstrom et al. showed for a lamellar amphiphile-water mesophase that this could be referred to double quantum transitions (37). It is expected that double quantum transition peaks appear in NMR spectra... 

Table 1 Activation energies for the p transition peak in PET and PET/additive from mechanical and dielectric measurements...

It has been recognised for a long time that the antiplasticisers induce a decrease of the f3 transition peak intensity [16]. 

Analysis of the motions involved in the f3 transition of BPA-PC clearly shows that the high-temperature part of the mechanical fi transition peak is associated with phenyl ring yr-flips. 

The dynamic mechanical analysis unambiguously shows that the antiplasticiser acts mainly on the cooperative motions involved in the high-temperature side of the j3 transition peak, implying several units. No effect is detected on the low-temperature side of the j3 peak. 

The activation energy and entropy associated with the maximum of the f3 transition peak are 83 5kJmol 1 and 51 =b 10 J K-1 mol-1, respectively. This value of the activation entropy, determined according to the Starkweather procedure (Sect. 2.3), corresponds to slightly cooperative motions at the maximum of the transition. 

Another point concerns the ji transition and the associated motions. Indeed, in PMMA the maximum of the /3 transition peak (Fig. 26) occurs around 10 °C, in such a way that the low temperature range corresponds to the low temperature part of the /3 transition, where the ester group motions are isolated, without any cooperativity with the main chain, and leading to multiple crazing, as described in Sect. 3.1.3.2. In contrast, in the case of MGIM76, the maximum of the f) peak is found around - 20 °C (Fig. 53), in such a way that the considered temperature range a is located in the high temperature part of the p transition, in which MGI-MGI cooperativity exists, as shown in [1] (Sect. 8.3). 

Considering the loss modulus /3 transition peak (Fig. 67a) and the downward temperature shift of about 20 °C (associated with the strain rate of 2 x 10 3 s 1 used in the experiments) it turns out that the temperature domain (around - 40 °C) where the behaviour change of oy occurs, corresponds to the end of the /3 transition. 

In the case of TMBPA-PC, the large shift of the p transition peak (Fig. 67) provides an opportunity to investigate the role of this transition in plastic deformation. 

For strain softening, the molecular mechanism proposed for BPA-PC can be considered. Thus, the increase of nSSA (Fig. 73) above 50 °C occurs in the high temperature part of the ft transition peak (shifted to lower temperature due to the 10 3 s 1 strain rate used in the experiments). Phenyl ring 7r-flips become active, associated with a development of intermolecular cooperativity, similar to that existing in BPA-PC in the temperature range of - 80 to... 

At the strain rate of the thin film deformation (KT4 s-1), the ft transition peak is shifted to - 130 °C in such a way that the temperature at which the SDZs appear (- 120 °C) in BPA-PC (Fig. 80) is well located in the high temperature part of the peak, where the cooperativity described above operates. 

Probes electronic transitions peaks are broadened by rotational, vibrational and solvent effects. The size of the peak depends on electronic energy spacing. 

The newly synthesized phenothiazine derivative 2-trifluoromethyl-10-[4-(methanesulfonylamido)butyl]-phenothiazine (FPhMS, see Fig. 1 for chemical structure) was also extensively studied in the context of its interaction with lipid bilayers. DSC was used to study the influence of this compound on model membranes formed from DMPE [80], DPPC [81], DMPC, and DMPG [82]. In all the studied lipid systems FPhMS (16) lowered Tm, caused broadening of transition peaks, and induced the decrease of AH. Melting temperatures were found to be reduced by the phenothiazine derivative to a similar extent when different lipids possessing acyl chains of the same length were compared. 

Organic C Forms Bond Examples Transition Peak Energy (eV)... 

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