I see my classroom making use of the many forms of technology that are available, including: PowerPoint presentations, electron microscopes, video conferencing, web-sites, and smart boards.
Scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDS) were used to observe intergranular and intragranular β-phase (Al3Mg2) formation and growth in as-received sample and long-term (~1 year) thermally treated samples of 5083-H131 alloy. Rod-shaped and equiaxed particles rich in Mn, Fe, and Cr were present in the as-received and heat treated samples. The β-phase precipitated along grain boundaries as well as around and between preexisting Mn-Fe-Cr rich particles. The measured thickness of β-phase along grain boundaries was lower than Zener–Hillert diffusion model predicted value and the potential reasons were theoretically analyzed. Dislocation networks, grain boundaries, and different preexisting particles were observed to contribute to Mg diffusion and β-phase precipitation.
transmission electron microscopy (TEM) - A form of microscope that uses a beam of instead of a beam of light (as in an optical microscope) to form a large image of a very small object. In optical microscopes the resolution is limited by the wavelength of the light. High-energy electrons, however, can be associated with a considerably shorter wavelength than light; for example, electrons accelerated to an energy of 105 have a wavelength of 0.004 enabling a resolution of 0.2 - 0.5 nm to be achieved. The has an electron beam, sharply focused by electron lenses, passing through a very thin specimen onto a fluorescent screen, where a visual image is formed. This image can be photographed.
One example of this problem is that under a light microscope the centrioles in an animal cell appear as one, however when viewed under an electron microscope we can see that there are two centrioles at right angles to each other....
While the compound microscope is most commonly used during our academic tenure, the electron microscope being an advanced model is used in high-end laboratories for carrying out extremely technical and critical research.