论文信息 - Electron scattering in ice and organic materials

Electron scattering in ice and organic materials

Scattering cross‐sections for the interpretation of the scattering‐absorption contrast of microscopical images of amorphous biological specimens are calculated. The constituent atoms are treated as independent particles and their atomic potential is approximated by a modified Lenz‐Wentzel potential. Both elastic and inelastic scattering processes are considered. Formulas of the effective elastic and inelastic atom scattering cross‐sections are derived for both a CTEM with hollow‐cone illumination and a STEM using an annular detector. The scattering‐absorption contrast is plotted as a function of the atomic number for a CTEM applying parallel illumination and a STEM using a dark‐field detector with maximum collection efficiency. The presented results are valid for acceleration voltages U in the range 20 kV

[1] R. Burge. Mechanisms of contrast and image formation of biological specimens in the transmission electron microscope , 1973 .

[2] G. Bahr,et al. Contributions to the quantitative interpretation of electron microscope pictures. , 1957, Experimental cell research.

[3] A. Engel. Molecular weight determination by scanning transmission electron microscopy. , 1978, Ultramicroscopy.

[4] R. Freeman,et al. Comparative mass measurement of biological macromolecules by scanning transmission electron microscopy , 1981, Journal of microscopy.

[5] F. Lenz. Zur Streuung mittelschneller Elektronen in kleinste Winkel , 1954 .

[6] M. Lamvik. Muscle thick filament mass measured by electron scattering. , 1978, Journal of molecular biology.

[7] G. Bahr,et al. A Photometric Procedure for Weight Determination of Submicroscopic Particles Quantitative Electron Microscopy , 1962 .

[8] M. Hahn. Properties of Commercial Films for Electron Microscopy , 1980 .

[9] R. Bonham,et al. New Values for the Partial Wave Electron Scattering Factor for the Elements 1≤Z≤57 and 72≤Z≤90 for Incident Electron Energies of 10, 40, 70, and 100 keV , 1971 .