Zuleima Karpyn in the Quantitative X-ray Imaging Lab. Credit: MRI
Friday, August 22, 2014

-Focus on Materials

When you think of CT scans, you probably imagine lying in a claustrophobic closed box while an X-ray machine clanks around you taking images of your body. In Penn State’s Center for Quantitative X-ray Imaging (CQI), the closed box is actually a large, lined room and the CT scanner is industrial size.

"Our scanner is mostly used to look at rocks and bones," says center co-director Zuleima Karpyn, an associate professor of petroleum and natural gas engineering, "but the common denominator is that everything we are looking at is a material – natural materials, synthetic materials, fabricated materials."

For many hard and soft materials, X-ray CT makes it possible to see what internal structures look like in three dimensions, nondestructively, and over time. Karpyn uses it primarily to look at the flow of liquids and gases through rock pores, and how that changes under varying environmental conditions, such as temperature and pressure. Her work has applications in oil and gas extraction technologies, as well as in Co2 sequestration.

"If you can detect density you can map structures," she continues. "You can also detect compositional features – one part is material A and another part is material B."

The open layout of the system makes it possible to have a variety of peripheral equipment, such as high pressure pumps and heaters, to provide environmental conditions that mimic geological conditions, such as the flooding of porous materials. The same techniques have been used to study the effects of water saturation in a PEM fuel cell. "Being able to connect your sample to peripheral equipment is one of the biggest advantages of this particular instrument," she says.

Because it is an open user facilities, outside companies have made use of the instrument and expertise of faculty and staff to inspect and measure a variety of materials and products, including batteries and catalysts, and even the distribution of air bubbles in chocolate and how that relates to texture. Read full article