review.html

Students will be taking, or have taken the lecture concurrently or previously.

Topic 1 Introduction to the TEM and SEM
Topic 2 Vacuum systems
Topic 3 Lenses/ electronics/TEM image formation/Detectors
Topic 4 SEM image formation/Detectors
Topic 5 TEM sample prep I
Topic 6 TEM sample prep II
Topic 7 TEM sample prep III
Topic 8 SEM sample prep
Topic 9 Recording images
Topic 10 Electron microscopy and X-Ray Microanalysis

Quizzes

Midterm

Pictures (if images are not visible or corrupted, click reload button and new images should appear)

Final exam review list

This represents a checklist of topics discussed over the semester. It is not complete, as I chose not to list everything mentioned in class. Furthermore, the review list touches on things you should know about, not necessarily in the order of the lectures. This is, after all, an attempt to tie things together. Two basic frameworks you might consider: 1) know the diagrams for all the equipment we discussed and how each piece operates, and 2) know the steps in sample preparation from raw sample to final image for both the TEM and the SEM. Make sure you know where the equipment in #1 above fits into the steps of #2. Be sure you understand the differences in preparations, and the need for them, for the TEM and SEM, including the specialized techniques such as negative staining, cytochemistry, immunological localization, shadow-casting, and freeze fracture. Know where these procedures fit into a generalized scheme of sample preparation .

Microscopes--an overview

This includes diagrams of the TEM and SEM columns, including locations of various parts, such as cameras, apertures, lenses. Discussions of how an image is formed and magnified in the TEM as compared to a SEM. The design of light, transmission and scanning electron microscopes. The workings of a scanning probe were mentioned, because of the atomic resolution possible with these machines compared to the TEM and SEM

Vacuum systems

The various gauges to measure vacuum, the pumps to create vacuum, and how pumps and valves are put together on a microscope to make it possible to vent the scope so samples can be inserted, then evacuated to high vacuum so samples can be viewed.

Lenses/ electronics

Lenses and how they work, and don't work. Problems inherent in lenses and how these problems are dealt with. How lenses are assembled into an SEM and a TEM to form and magnify an image

Photography/ recording images

Recording images, using film and computers. How film is built, exposed and processed, and the different kinds of film available. Images are also collected digitally, using computers coupled in some cases to YAG scintillators. There are pluses and minuses to using film versus computers. Finally, how do you print a digital image--how an inkjet and a laser printer do their thing.

Transmission Electron Microscopy

TEM Sample preparation I. An overview of the process from live cells to finished images. The different ways to preserve cells, using chemicals versus cold, and the pluses and minuses of each.

TEM Sample preparation II. The cells, once preserved then need to be further processed. If small enough, they can be negatively stained and viewed, shadowed and viewed, or embedded in plastic and sliced. There are intricacies to all of these steps, and I expect you can comment about all of them.

TEM Sample preparation III. The cells, after slicing, need to have contrast enhancement, since most biological material lacks much contrast. This leads to a discussion of the different interactions of the beam with the sample and how this interaction leads to the images we see. Although staining the samples gives better contrast, it doesn't always reveal the location of specific structures or materials. To do this may require specific staining procedures such as cytochemical or immunological localizations. The steps involved in both of these procedures were discussed.

Scanning Electron Microscopy

Secondary and Backscatter detectors, and basic sample preparation, including ways to dry and coat sample were covered.

Electron Microscopy and X ray analysis

Chemical analysis is also possible with electron microscopes, in addition to the morphological analyses we have covered to date. How x-rays are generated, named, and detected (EDS vs. WDS), and some of the operating parameters and artifacts were explained.

Freeze-fracture/etch

Up until the development of the scanning probe microscopes (discussed in earlier lectures), this was the technique of choice for visualizing proteins in membranes. It combines rapid freezing preparation, shadow-casting replicas, and dissolving away your sample to view a thin coating of carbon-metal with the surface morphology of your sample, proteins and all.