Deposit spectrum

Figure 5 shows representative spectra for test 4, an unstable case. The maximum of the deposited spectrum occurs at 10 y. Since 10 y droplets have quite poor impaction efficiency, this finding suggests that the proportion of very small drops emitted by the aircraft must be very large indeed. Earlier studies (10) of the TBM emitted spectrum have severely underestimated these numbers due to problems associated with measuring in-flight drops smaller than about 30 y. Recent studies using a laser spectrometer are expected to clarify this point (11). 

One aspect of the deposited spectrum which is of particular practical significance is its relationship to the evaporated emitted spectrum. We have seen that the evaporated vmd is approximately 58 y a value considerably lower than is commonly used with ultra low volume applications. Yet, of 5000 droplets sized on fir needles 90A% were smaller than 60 y. Since this method of application has proven efficacious over millions of hectares of New Brunswick forest, one must conclude, yet again, that small drops are not merely effective but, in all likelihood, are responsible for the bulk of insect mortality. 

Figure 8.6. Example of quenching in a beta-particle energy deposition spectrum in an LS counter.

For the deposit/substrate system the total measured spectrum is simply the sum of the substrate spectrum and the deposit spectrum (noninterfering peaks are of course best suited for the analysis). As the two distribution functions are com-... 

Figure 1 The FTIR spectrum of the oxide of siiicon (thin film deposited by CVD). Primery...

Figure 1 shows a segment of the FTIR absorbance spectrum of a thin film of the oxide of silicon deposited by chemical vapor deposition techniques. In this film, sil-... 

Fig. 2 shows one application of ATR depth profiling. In this case, ATR spectra were obtained as a function of angle of incidence from a polymethylmethacrylate (PMMA) film of thickness 0.5 p.m that was deposited onto a germanium hemi-cylinder [4]. The solid line represents the ATR spectrum of PMMA while the squares represent the film thickness that was recovered from the infrared spectra using four different bands. It can be observed that the recovered film thickness was very close to the measured thickness. 

This characteristic of RAIR can be observed experimentally. Fig. 8 shows the transmission spectrum of polydimethylsiloxane (PDMS) while Fig. 9 shows the RAIR spectrum of a thin film of PDMS spin-coated onto a chromium substrate. It can be observed that the bands near 1024 and 1095 cm have similar intensities in the transmission spectra but the band at higher frequencies is clearly much more intense in the RAIR spectrum. This change in relative intensity when PDMS is deposited onto a reflecting substrate is related to optical effects and is not related to orientation effects. 

Observation of absorption bands due to LO phonons in RAIR spectra of thin, silica-like films deposited onto reflecting substrates demonstrates an important difference between RAIR and transmission spectra. Berreman has shown that absorption bands related to transverse optical (TO) phonons are observed in transmission infrared spectra of thin films obtained at normal incidence [17]. However, bands related to LO phonons are observed in transmission spectra of the same films obtained at non-normal incidence and in RAIR spectra. Thus, it is possible for RAIR and transmission spectra of thin films of some materials to appear very different for reasons that are purely optical in nature. For example, when the transmission infrared spectrum of a thin, silica-like film on a KBr disc was obtained at normal incidence, bands due to TO phonons were observed near 1060,790,and450cm [18]. 

The XPS survey spectrum of a 75 nm thick film of plasma polymerized acetylene that was deposited onto a polished steel substrate is shown in Fig. 18 [22]. This film consisted mostly of carbon and a small amount of oxygen. Thus, the main peaks in the spectrum were attributed to C(ls) electrons near 284.6 eV and 0(ls) electrons near 533.2 eV. Additional weak peaks due to X-ray-induced O(KVV) and C(KLL) Auger electrons were also observed. High-resolution C(ls) and 0(ls) spectra are shown in Fig. 19. The C(ls) peak was highly symmetric. 

Fig. 18. XPS survey spectrum of a plasma-polymerized acetylene film with a thickness of 75 nm that was deposited onto a polished steel substrate. Reproduced by ptermission of John Wiley and Sons from Ref. [22].

Positive SIMS spectra obtained from plasma polymerized acetylene films on polished steel substrates after reaction with the model rubber compound for times between zero and 65 min are shown in Fig. 44. The positive spectrum obtained after zero reaction time was characteristic of an as-deposited film of plasma polymerized acetylene. However, as reaction time increased, new peaks appeared in the positive SIMS spectrum, including m/z = 59, 64, and 182. The peaks at 59 and 64 were attributed to Co+ and Zn, respectively, while the peak at 182 was assigned to NH,J(C6Hn)2, a fragment from the DCBS accelerator. The peak at 59 was much stronger than that at 64 for a reaction time of 15 min. However,... 

Gallium was predicted as eka-aluminium by D. 1. Mendeleev in 1870 and was discovered by P. E. Lecoq de Boisbaudran in 1875 by means of the spectroscope de Boi.sbaudran was, in fact, guided at the time by an independent theory of his own and had been searching for the missing element for some years. The first indications came with the observation of two new violet lines in the spark spectrum of a sample deposited on zinc, and within a month he had isolated 1 g of the metal starting from several hundred kilograms of crude zinc blende ore. The... 

The evolution of the XPS C(ls), S(2p), and Al(2p) core level lines, upon A1 deposition onto poly(3-octylthiophene) films (P30T), is shown in Figure 5-15 [84. The S(2p) spectrum for the pristine polymer consists of two components, S(2p 1/2) and S(2p.v2), due to spin-orbit coupling. 

The XPS S(2p) core level spectra recorded during the stepwise deposition of copper onto poly(3-hcxyllhiophenc), or P3HT [88] are shown in Figure 5-17. The S(2p) spectrum at the lop correspond to the pristine system. On increasim copper... 

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