Conventional direct space techniques

Both the Doppler slice and the ion TOP measurement are essentially in the centre-of-mass system. Therefore the measurement directly maps out the desired 3D centre-of-mass distribution, i.e. d aj v dv dO = I 6,v) v in Cartesian velocity coordinates (d (r/diVx dvy dv ). Thus, the double differential cross-section I 6,v) is obtained by multiplying the measured density distribution in the centre-of-mass velocity space by and then transforming from the Cartesian to the polar coordinate system. This procedure has to be contrasted against the conventional neutral TOP technique (either in the universal machine or by the Rydberg-tagging method), for which the laboratory to centre-of-mass transformation must be performed, or against the 2D ionimaging technique, which involves 2D to 3D back transformation. 

TEM is still the most powerful technique to elucidate the dispersion of nano-filler in rubbery matrix. However, the conventional TEM projects three-dimensional (3D) body onto two-dimensional (2D) (x, y) plane, hence the structural information on the thickness direction (z-axis) is only obtained as an accumulated one. This lack of z-axis structure poses tricky problems in estimating 3D structure in the sample to result in more or less misleading interpretations of the structure. How to elucidate the dispersion of nano-fillers in 3D space from 2D images has not been solved until the advent of 3D-TEM technique, which combines TEM and computerized tomography technique to afford 3D structural images, incidentally called electrontomography . 

In addition to the conventional application of nmr pulsed field gradient experiments to self-diffusion studies, it is also possible to determine the intracrystalline molecular life times. Referring to the corresponding classical experiment, this method has been termed nmr tracer desorption technique (7). Together with the self-diffusion measurements it provides an excellent tool for characterizing the transport properties in the intra- and intercrystalline spaces, as well as at the interface between them. So far, the nmr techniques provide the only possibility for a direct determination of the existence and of the intensity of transport resistances at this... 

ESA leads to an obstruction, for example, the ovens, Knudsen cells, etc. needed for deposition of thin films prevent a direct view of the substrate. This is one reason why RHEED is in rather widespread use in thin-film deposition systems—the electron gun and screen are remote and grazing incidence does not interfere with film deposition. Therefore, in many cases RHEED is a real in situ technique. By comparison, the conventional front view LEED system blocks essentially the full space and the rear view system blocks half of the space available. In this respect MEIS and RBS are also remote systems that do not take much space around the substrate or target. In some systems transport is installed as a solution (it is the only solution when adding STM to the tool box). 

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