Determination of Beam Quality Correction Factors for the PTW-Markus Chamber for Electron Beam QualitiesR50=1.0 and 1.4 g/cm2

The invisibility criterion which is the standard technique for determining the nature of dislocations seen in the electron microscope can at times lead to erroneous results or at best cause confusion in many cases since the dislocation can still show a residual image if the term is non-zero, or if the edge and screw displacements are anisotropically coupled, or if the dislocation has a mixed character. The symmetry criterion discussed below can be used in conjunction with and in some cases supersede the invisibility criterion for obtaining a valid determination of the nature of the dislocation.The symmetry criterion is based upon the well-known fact that a dislocation, because of the symmetric nature of its displacement field, can show a symmetric image when the dislocation is correctly oriented with respect to the electron beam.

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Enhanced information from biological materials through technological improvements in cryo-electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124343 ◽

1992 ◽

Vol 50 (1) ◽

pp. 788-789

Author(s):

Marc J.C. de Jong ◽

Wim M. Busing ◽

Max T. Otten

Keyword(s):

Electron Microscopy ◽

Electron Beam ◽

Biological Materials ◽

Electron Crystallography ◽

Cryo Electron Microscopy ◽

Transmission Electron ◽

The Many ◽

Technological Improvements ◽

Beam Damage

Biological materials damage rapidly in the electron beam, limiting the amount of information that can be obtained in the transmission electron microscope. The discovery that observation at cryo temperatures strongly reduces beam damage (in addition to making it unnecessaiy to use chemical fixatives, dehydration agents and stains, which introduce artefacts) has given an important step forward to preserving the ‘live’ situation and makes it possible to study the relation between function, chemical composition and morphology.Among the many cryo-applications, the most challenging is perhaps the determination of the atomic structure. Henderson and co-workers were able to determine the structure of the purple membrane by electron crystallography, providing an understanding of the membrane's working as a proton pump. As far as understood at present, the main stumbling block in achieving high resolution appears to be a random movement of atoms or molecules in the specimen within a fraction of a second after exposure to the electron beam, which destroys the highest-resolution detail sought.

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The determination of correction factors for free-air ionization chamber calculation using monte carlo method

Journal of Physics Conference Series ◽

10.1088/1742-6596/1719/1/012043 ◽

2021 ◽

Vol 1719 (1) ◽

pp. 012043

Author(s):

P Rindhatayathon ◽

K Koonkana ◽

V Pungkun

Keyword(s):

Monte Carlo ◽

Monte Carlo Method ◽

Ionization Chamber ◽

Correction Factors ◽

Free Air ◽

Air Ionization

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Determination of grain‐boundary parameters of polycrystalline silicon by ac electron‐beam‐induced current

Journal of Applied Physics ◽

10.1063/1.341238 ◽

1988 ◽

Vol 64 (9) ◽

pp. 4601-4608 ◽

Cited By ~ 1

Author(s):

A. Romanowski ◽

D. B. Wittry

Keyword(s):

Electron Beam ◽

Grain Boundary ◽

Polycrystalline Silicon ◽

Induced Current ◽

Electron Beam Induced Current

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Cathodoluminescence of SiO2/Si System

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.156-158.487 ◽

2009 ◽

Vol 156-158 ◽

pp. 487-492 ◽

Cited By ~ 1

Author(s):

M.V. Zamoryanskaya

Keyword(s):

Activation Energy ◽

Electron Beam ◽

Rise Time ◽

Silicon Oxide ◽

Beam Current ◽

Electron Beam Current ◽

Electron Traps ◽

Definition Of ◽

Luminescent Centers

In this paper the new method for determination of luminescent centers concentration are discussed. While the possibility of electron traps determination and definition of its activation energy are suggested. The cathodoluminescent (CL) method was used. The determination of luminescent centers concentration in silicon oxide is based on the measurements of dependences of CL intensity on electron beam current. The presence and energy of activation of electron traps were studied by measurement of rise time and decay of luminescent band during the stationary irradiation of silica by electron beam.

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