Incident angle

We are interested in < E (0[,(t)i)E3(62,, where <> means the average over the ensemble of surfaces, the subindexes 1 and 2 refer to two different points of observation and the subindexes A and B belong to two different conditions of illumination, which for example arise from two different wavelengths, two different incident angles, etc.. If A = B and 1 = 2, the above expression gives the angular distribution of the mean scattered intensity, otherwise it turns to be the intensity correlation coefficient y from < E Eb >, assuming that we deal with fully developed speckle. 

Fig.3 Diffracted signal amplitude at various incident angles for different EMAT distances...

The angle of refraction 0 of the probe as well as the incident angle a are given by the equation(5)... 

The echo directivity was influenced by the test frequency, the angle of refraction (the velocity in the wedge and the incident angle), and the height of the transducer. 

Madey and co-workers followed the reduction of titanium with XPS during the deposition of metal overlayers on TiOi [87]. This shows the reduction of surface TiOj molecules on adsorption of reactive metals. Film growth is readily monitored by the disappearance of the XPS signal from the underlying surface [88, 89]. This approach can be applied to polymer surfaces [90] and to determine the thickness of polymer layers on metals [91]. Because it is often used for chemical analysis, the method is sometimes referred to as electron spectroscopy for chemical analysis (ESCA). Since x-rays are very penetrating, a grazing incidence angle is often used to emphasize the contribution from the surface atoms. 

Illuminating the sample at grazing angles. The penetration depth of photons depends on the cosine of the incidence angle and, therefore, can be reduced by this procedure. Although such an approach has limited use, it has been successfully employed in a few instances, such as for x-ray diffraction experiments. 

Figure Bl.23.8. Scattering intensity of 2 keV Ne versus azimuthal angle 6 scans for Pt 110] in the (1 x 2) and (1 X 3) reconstructed phases. Scattering angle 0 = 28° and incident angle a = 6°.

Special contact transducers having wedges providing incidence angles for specific appHcations are used widely in industry. For example, normal incidence is used in tests for laminations within sheets, and for sheet or plate thickness where the back surface of the test material parallels, to within perhaps 10°, the front surface. Shear wave transducers typically used for weld examination have 45°, 60°, or 70° inspection (refracted) angles. To locate discontinuities, the transducers may be moved back and forth over selected surface areas until the angled search beam approaches normal incidence on the... 

The ocean is an integral part of the climate system. It contains almost 96% of the water in the Earth s biosphere and is the dominant source of water vapour for the atmosphere. It covers 71% of the planet s surface and has a heat capacity more than four times that of the atmosphere. With more than 97% of solar radiation being absorbed that falls on the surface from incident angles less than 50" from the vertical, it is the main store of energy within the climate system. 

Vaned diffuser ioss. Vaned diffuser losses are based on conical diffuser test results. They are a function of the impeller blade loading and the vaneless space radius ratio. They also take into account the blade incidence angle and skin friction from the vanes. 

The incidence angle o is for a 10% blade thickness. For blades of other than 10% thickness, a correction factor K is used, which is obtained from Figure 7-25. 

The incidence angle now must be corrected for the Mach number effect The effect of the Mach number on incidence angle is shown in Figure 7-26. The incidence angle is not affected until a Mach number of. 7 is reached. 

The incidence angle is now fully defined. Thus, when the inlet and outlet air angles and the inlet Mach number are known, the inlet blade angle can be computed in this manner. 

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