Electron imaging experiment

The output of imaging experiments is readily comprehensible to non-spectroscopists (comparable to light and electron microscopy). 

Such an experimental characterization is a necessary step to carry out a detailed comparison of emission properties as measured experimentally with the corresponding quantities as calculated by numerical models capable of describing transport and energy deposition of fast electrons in matter and consequent emission of characteristic X-ray emission. A possible modeling approach of fast electron transport experiments is given here, where the above results on Ka imaging were interpreted using the hybrid code PETRA [53] to... 

As shown above, the size and distribution of minute particles are conveniently investigated by high-resolution STEM with a HAADF detector (60,63). The intensity in HAADF images is a monotonic function of the sample thickness and atomic number, a pre-requisite for the electron tomography experiments described below. 

The hypothesis of a normal distribution is a strong limitation that should be always kept in mind when PCA is used. In electronic nose experiments, samples are usually extracted from more than one class, and it is not always that the totality of measurements results in a normally distributed data set. Nonetheless, PCA is frequently used to analyze electronic nose data. Due to the high correlation normally shown by electronic nose sensors, PCA allows a visual display of electronic nose data in either 2D or 3D plots. Higher order methods were proposed and studied to solve pattern recognition problems in other application fields. It is worth mentioning here the Independent Component Analysis (ICA) that has been applied successfully in image and sound analysis problems [18]. Recently ICA was also applied to process electronic nose data results as a powerful pre-processor of data [19]. 

Surface area of as-obtained CNF is nearly 300-500 m2/g. One of the effective methods of activation of different carbon materials is treatment with melted KOH at 400-900°C. High surface area (up to nearly 3000 m2/g) carbon materials were obtained [16, 17]. This method was also applied to carbon nanotubes. Significant development of surface was observed, from 465 m2/g for starting MWNT to 1184 m2/g after activation [18], Also, KOH activation of carbon nanofibers resulted in increase of surface area from initial 174 m2/g up to 1212 m2/g [19]. When activated our nanofibers, we obtained for some samples very high effective surface area, nearly 2000-4000 m2/g and in some experiments even 6000 m2/g (measured by argon desorption method). In electron image of activated material (Fig. 7) fiber-like structure is observed. 

The xenon atom can therefore be used as a delicate probe to determine the number of surrounding water molecules and their orientations. These results demonstrate the sensitivity of the easily polarizable xenon electronic structure to the electrostatic properties of its surrounding and the great potential for achieving accurate interpretations of magnetic resonance parameters from imaging experiments with hyperpolarized xenon. 

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