The Study of Electron Channeling and Channeling Radiation Using High-Voltage Electron Microscopes

1987 ◽  
pp. 299-304
Author(s):  
F. Fujimoto
Keyword(s):  
High Voltage ◽  
Electron Channeling ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes ◽  
Channeling Radiation

scholarly journals The Largest Possible Microscope

1994 ◽  
Vol 2 (5) ◽  
pp. 10-10
Author(s):  
Sterling P. Newberry
Keyword(s):  
High Voltage ◽  
Focal Length ◽  
Big Science ◽  
Distinguishing Characteristic ◽  
Voltage Electron ◽  
Science Projects ◽  
High Voltage Electron ◽  
Ordinary Light ◽  
Electron Microscopes ◽  
Ultra High Voltage

In this day of resistance toward big science projects it may be futile to worry about how to produce the largest possible microscope. But since it doesn't cost anything to day dream, and times may change, it is fun to consider superlative enterprises.One must grant that Ultra High Voltage Electron Microscopes are much larger than we wish they were, and one wonders if there is a contest afoot to see which AEM can have the largest foot print, but a new possibility has arisen which, seriously, could dwarf them all - yet have some possible use.I am referring to the discovery of an example of a gravitation lens for ordinary light. Now the distinguishing characteristic of a microscope from a telescope is that the object eyepiece and the object near the focal length of the lens.

A side-entry high-precision tilt stage for a high-voltage Electron Microscope

1986 ◽  
Vol 44 ◽  
pp. 628-629
Author(s):  
J.N. Turner ◽  
D.P. Barnard ◽  
G. Matuszek ◽  
C.W. See
Keyword(s):  
Electron Microscope ◽  
High Precision ◽  
High Voltage ◽  
Three Dimensional ◽  
Three Dimensional Reconstruction ◽  
Voltage Electron ◽  
High Voltage Electron Microscope ◽  
High Voltage Electron ◽  
Dimensional Reconstruction ◽  
Electron Microscopes

A high precision specimen stage is essential for the accurate recording of images for three-dimensional reconstruction. The efficient calculation and resolution of a “tomographic type” three-dimensional reconstruction is influenced by the precision of the angular tilt settings. The ability to identify structures at low magnification and later return to them for detailed study at high magnification is crucial to the efficient study of structures by serial section reconstruction, and is greatly aided by a precise, repeatable translation stage. To study such problems, we have designed and fabricated a single-tilt specimen stage for our high-voltage electron microscope (HVEM), which represents a different design philosophy to that usually employed in side entry stages for transmission electron microscopes.

In-situ studies in the high-voltage Electron Microscope

1990 ◽  
Vol 48 (4) ◽  
pp. 504-505
Author(s):  
K.H. Westmacott
Keyword(s):  
Phase Transitions ◽  
High Voltage ◽  
Bulk Material ◽  
Outer Region ◽  
High Energy ◽  
Research Areas ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes

The principal advantages of high voltage electron microscopes are the ability to 1) attain higher resolution by virtue of the shorter wavelength, and 2) penetrate thicker specimens to observe dynamic behavior representative of bulk material. Some recent examples of in-situ HVEM research, representing the latter category, will be summarized in this contribution, and future directions discussed. Included in the most active research areas are phase transitions, deformation, high temperature reactions and environmental cell studies.Irradiation with high energy electrons in an HVEM provides a convenient alternative to thermal treatments for inducing phase transitions in alloys. An illustration of how ordering or disordering of the same material can occur under electron irradiation is shown in Figure 1. In this example, a Pt7C ordered phase was formed in a Pt-C alloy at 500°C with a defocused beam (outer region) and subsequently disordered at 30°C with a focussed beam (inner spot).

Lenses for high voltage electron microscopes

Micron (1969) ◽  
1969 ◽  
Vol 1 (3) ◽  
pp. 265-266
Author(s):  
J.H. Reisner
Keyword(s):  
High Voltage ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes

Increasing Access to Tomographic Resources: Web-based Telemicroscopy and Database

2001 ◽  
Vol 7 (S2) ◽  
pp. 92-93
Author(s):  
M. E. Martone ◽  
S. Peltier ◽  
S. Lamont ◽  
A. Gupta ◽  
B. Ludaescher ◽  
...  
Keyword(s):  
Golgi Apparatus ◽  
High Voltage ◽  
Cell Biology ◽  
Electron Tomography ◽  
The United States ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes

The application of electron tomography to cell biology has led to important insights into the 3D fine structure of subcellular processes and organelles. Tomography has been particularly useful for studying relatively large, multi-component structures such as the Golgi apparatus, mitochondria and synaptic complexes. When combined with very powerful high voltage electron microscopes, tomography has also provided high resolution quantitative views of extended structures such as neuronal dendrites in very thick sections (4 μm) at electron microscopic resolution. The utility of tomography is twofold: first, it provides 3D examination of subcellular structure without the need for serial section analysis; second, because the computed slices through the tomographic volumes can be much thinner than is possible to produce by physical sectioning, it reveals structural detail in the range of 5-30 nm that tends to be obscured in conventional thin sections. Tomographic analysis has forced re-assessment of long-standing views of organelles such as mitochondria and the Golgi apparatus and as the technique advances, additional insights are likely forthcoming.Electron tomography is an expensive technique, both in terms of the instruments used and the computational resources required. The three major high voltage electron microscope resources in the United States, San Diego, Boulder and Albany, all are actively engaged in tomographic research and offer this important technology to the scientific community at large.

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