Experiment design for determination of transverse energy profile field emitted electron beam

Author(s):  
P.M. Phillips ◽  
E.G. Zaidman ◽  
C. Hor ◽  
L. Malsawma
Author(s):  
J. C. Ingram ◽  
P. R. Strutt ◽  
Wen-Shian Tzeng

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.


Author(s):  
Marc J.C. de Jong ◽  
Wim M. Busing ◽  
Max T. Otten

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.


2009 ◽  
Vol 156-158 ◽  
pp. 487-492 ◽  
Author(s):  
M.V. Zamoryanskaya

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.


2012 ◽  
Vol 422 (1-3) ◽  
pp. 86-91 ◽  
Author(s):  
P.D. Edmondson ◽  
W.J. Weber ◽  
F. Namavar ◽  
Y. Zhang

2004 ◽  
Vol 50 (5) ◽  
pp. 227-234 ◽  
Author(s):  
M. Petrovic ◽  
P. Gehringer ◽  
H. Eschweiler ◽  
D. Barceló

A commercial blend of nonylphenol ethoxylates (NPEOs) was chosen as representative for non-ionic polyethoxylated surfactants to study the oxidative degradation of this class of surfactants in water using ozonation as well as electron beam irradiation with and without the addition of ozone as treatment processes. The electron beam irradiation processes applied represent so-called Advanced Oxidation Processes (AOPs); the combined ozone/electron beam irradiation is, moreover, the most powerful AOP which can be applied in aqueous systems. It was found that both ozonation and the two AOPs applied were able to decompose not only the NPEOs but also the polyethyleneglycoles (PEGs) formed as by-products from NPEO degradation to residual concentrations below the limit of detection. Moreover, the treatment processes were also used to study the oxidative degradation of nonylphenoxy acetic acid (NPEC) and of nonylphenol (NP) which are formed as by-products from biodegradation of NPEOs.


1989 ◽  
Vol 50 (C6) ◽  
pp. C6-174-C6-174
Author(s):  
M. VALENZA ◽  
P. GIRARD ◽  
B. PISTOULET
Keyword(s):  
Low Dose ◽  

Author(s):  
V. I. Barsukov ◽  
◽  
O. S. Dmitriev ◽  
A. A. Barsukov ◽  
◽  
...  

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