Nanomaterials for Nanoscience and Nanotechnology part 6 pdf

... the valence band. The difference between Figures 3-23b and 3-23c is the emission of photon in the former and the Auger electron in the latter, and the two processes are complimentary. 62 Wang Figure ... atoms. This type of information is most useful in material analysis and the integrated intensity is given by I A (Á) % I 0 (Á)  A (Á,) n A d (3-22) 66 Wang Figure 3- 26. An EELS sp...

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... 1992. [63 ] M. Pan, J. M. Cowley, Ultramicroscopy 1988, 26, 205. [64 ] J. M. Cowley, J. C. H. Spence, Ultramicroscopy 1981, 6, 359. [65 ] J. Zhu, J. M. Cowley, Acta Cryst. 1982, A38, 718. [66 ] J. ... the center of the particles. Further particle analyses can be performed on this type of ªcleanº image, yielding information about the size distribution and the composition of the particle...

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... levels, bands are formed. An energy gap between the con- duction band and the valence band would be formed, which is a key factor in deter- Nanomaterials for Nanoscience and Nanotechnology 5 Part ... Forro, Adv. Materials, 1999, 11, 161 . [61 ] M.M. Treacy, T.W. Ebbesen, J.M. Gibson, Nature, 19 96, 38, 67 8. [62 ] P. Poncharal, Z.L. Wang, D. Ugarte and W.A. de Heer, Science...

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... information about the particle size and exter- nal form is concentrated. No details of the internal atomic arrangements are con- tained in the small-angle intensity distribution (see [3,4 ,6] for ... heights and widths [8]. Figure 2-1 shows the diffraction patterns for three sizes of face-centered- cubic (fcc) particles, spanning a diameter range of 1 .6 2.8 nm, and containing from...

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... Phys. 1 967 , 18, 175. [9] J. B. Cohen, Ultramicroscopy 1990, 34, 41. [10] S. Ino, J. Phys. Soc. Japan 1 966 , 21, 3 46; S. Ino and D. Ogawa, J. Phys. Soc. Japan 1 967 , 22, 1 365 ; J. G. Allpress and J. ... H. Tolentino for stimulating discussions. DZ and DU are indebted to FAPESP (Con- tracts 96/ 12550±8, 97/042 36- 4) and CNPq for funding. BDH gratefully acknowledges financial...

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... Facets tend to form on the particle surface to increase the portion of the low index planes. Therefore, for particles smaller than 10- 20 nm, the surface is a polyhedron. Figure 3-6a shows a group ... The surface of the particle may have some steps and ledges particularly at the regions near the corners of the cube. To precisely image the defects and facets on the cubic parti- cles, a p...

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... overlapping discs. The numeral 2 stands for two- beam interference, 3 for three-beam interference, 4 for four-beam interference, and the letter D indi- cates detector positions for dark-field lattice imag- ing. The ... designed for the study of nanostructures of surfaces and small particles with high spatial resolution. The various 86 Liu STEM imaging, analytical, and diffra...

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... of Nanoparticles 103 Figure 4- 16. Intensity and radius data from particles in HAADF and SE images of silver nanoparticles plotted as (intensity) 1/3 against particle radius R. The HAADF and SE ... structure, and composition of metal parti- cles is of primary importance in understanding the synthesis-structure-activity rela- tionships and is essential for a qualitative and quant...

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... with the size of the particle and the highest image inten- sity is approximately at a distance d =(R ± L) from the center of the particle. For very large particles, the particle contrast evolves ... electrons from spherical particles of different sizes and the corresponding SE intensity line-scans across the particles. The parameters R and L represent the particle radius and the ave...

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... Forro, Adv. Materials, 1999, 11, 161 . [61 ] M.M. Treacy, T.W. Ebbesen, J.M. Gibson, Nature, 19 96, 38, 67 8. [62 ] P. Poncharal, Z.L. Wang, D. Ugarte and W.A. de Heer, Science, 1999, 283, 1513. Nanomaterials ... nanocrystals and emphasize how the struc- tures and the properties are characterized using the techniques presented in the book. Nanomaterials for Nanoscience and...

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