App State is granted with new scanning electronic microscope


The Appalachian Online

Angela McLinton

Appalachian State’s Dewel Microscopy Facility was awarded a scanning electron microscope, valued at $562,842, through a major research instrumentation program by the National Science Foundation. 

“The SEM (Scanning Electron Microscope) is ideal for imaging the surfaces of small objects and identifying what they are composed of. The entire Microscopy Facility operated by the College of Arts and Sciences is focused on doing this with different instruments,” Ellen Cowan, sedimentary record of climate change, geoarchaeology and geomorphology professor, said.

While this SEM is not the first to be seen within the UNC school system, it is more state-of-the-art, with more features and capabilities.

“One of the most cutting-edge features is the electron backscatter diffraction detector which allows us to determine the orientation of individual grains in a sample,” Jamie Levine, assistant professor of structure, tectonics and metamorphic petrology, said. “This can tell us about the temperatures the rock experienced and what kind of deformation or changes in shape of the crystals occurred. These are really important constraints for understanding how mountain ranges form and break down.”

“Another capability we have is to image cathodoluminescence,” Gabriel Casales, assistant professor of structural geology, said. “CL is the property of some materials to glow when excited by a cathode ray. Old tube televisions are actually cathode ray tube televisions, and the picture was generated by exciting the inner lining of the television screen with a cathode ray. On the SEM, some things that are not visible normally will luminesce and become visible.”

To have been awarded this expensive piece of equipment and its accessories, faculty from the College of Arts and Sciences had to submit a proposition.

“Dr. Sarah Carmichael from the department of geological and environmental sciences took the lead along with four other faculty in writing a proposal to the National Science Foundation for a major research instrument grant,” Cowan said. “We received the grant last year and the instrument was installed in February. After extensive testing and training we were able to run it full time in late spring.”

The SEM can be used within multiple scientific disciplines and encourages the involvement of undergraduate students.

“The SEM is a workhorse instrument. Biologists, geologists, physicists, anthropologists—pretty much anyone can find a use for it if you need to look at really tiny things or understand the structures of materials,” Sarah Carmichael, associate professor of the department of geological and environmental sciences, said.

“Because of all of these applications, the SEM allow us to incorporate its use into a huge range of disciplinary studies. This versatility fosters a shared expertise across disciplines that promotes multidisciplinary collaboration,” Casales said. “For a number of us, the SEM forms the cornerstone of our student mentoring and development efforts.”

The distinction with this microscope and App State is that there is more of a focus with undergraduate students and their involvement with advanced equipment.

“This facility is not just a fancy piece of equipment there for the exclusive use of a few faculty,” Casales said. “This is a facility that is operated unsupervised, on a daily basis by undergraduates who have gained high level training and are conducting their own advanced research projects.”

The caliber at which the SEM works is intense, as its capabilities by far succeed those of older microscopes.

“If you want to know how a rock or a material is structured, it can do that,” Carmichael said. “If you want to see something magnified by 100,000, it can do that. If you want to know the chemistry of a material or a rock or a biological specimen, it can do that.”

Not just anyone can walk in and use the SEM, however. Students who have been trained and are working on research projects mentored by faculty are permitted usage. “It is generally fairly user friendly, but it does require training,” Levine said.

“It’s a bit complicated to use. Some aspects are more complex than others,” Carmichael said. “If you’re just taking pictures, it’s pretty easy to use. If you’re trying to figure out the chemistry of your sample, it’s a more complex process. If you are trying to figure out the structure and orientation of a rock or a material, it’s really pretty difficult.”

The SEM could potentially make Appalachian State a more appealing prospective school, especially considering that disciplines like geology are undergraduate only.

“Students who use the SEM can use the data they acquire to present their research at national conferences, and they can write manuscripts and senior theses on their research,” Levine said. “Both of these things are important for learning how the scientific method works and for getting into graduate school.”

The microscopy facility, the home of the SEM, has several other high-end machines, including a confocal laser scanning microscope and a transmission electron microscope, run by Guichuan Hou, a biology research professor.

“Appalachian State has a wide array of amazing equipment that rivals R1 universities, not only in the microscopy facility but also in individual departments. These instruments are all being used for different purposes around the university,” Carmichael said.

Story by: Angela McLinton, News Reporter