After Café

WHEN: Select Tuesdays 11:00 AM - 11:45 AM, September 24 - November 19, 2024

WHERE: 3rd Floor Commons, Millennium Science Complex

WHO: Any student, staff, or faculty interested in learning more about MCL capabilities

A casual opportunity immediately following the Millennium Café to learn about the breadth of analytical capabilities within the Materials Characterization Laboratory (MCL).  These brief (30 minute) multi-technique and interdisciplinary talks will highlight applications (not theory) to provide useful insights to novice and experienced researchers working across various science and engineering challenges.

After Café Fall 2024 Series

After Café: More than Just a Picture: Integrating CT into Research

Computed tomography (CT) is a non-destructive technique that is used to investigate the 3D structure in a wide range of materials of both biologic and synthetic origin, from manufactured metal parts to delicate insect specimens. With this technique, samples can be analyzed ranging from the size of cockroach antenna to a bear skull. Using image analysis software, visualization, processing, and quantification of internal and external features can produce eye-catching images, videos, and both quantitative and qualitative information, all with little to no harm to the sample. I will discuss different ways to utilize CT images in your research. 

Michelle Quigley, Assistant Research Professor, Institute of Energy and the Environment, Energy and Environmental Sustainability Laboratories, Center for Quantitative Imaging 

After Café: Rigor Matters: Accurate Analyses at Elevated Temperatures

Many areas of research characterize samples under standard conditions and attempt to extrapolate these results to temperatures or an atmosphere far from ambient.  Numerous non-ambient capabilities are available within MCL, these require careful planning and special hardware, but the data collected under non-ambient conditions can be invaluable.  Variable temperature accessories are perhaps the most convenient and commonly used for non-ambient analysis.  However, there are no accessories where the controller setpoint accurately reflects the sample temperature at the location being analyzed.  This talk will highlight two methods (FTIR and XRD) where the MCL has developed accurate and precise temperature calibration protocol. 

Jordan Meyet
After Café: Thermal Analysis Capabilities, Trade Offs, and Limitations

While thermal property analyses (TGA, DSC, SDT) are often considered routine techniques the published literature demonstrates that these are frequently misused or underutilized.  I will review the capabilities of the MCL thermal analysis suite to include highlighting the less obvious information that can be obtained with each technique.  Additionally, the tradeoffs associated with each technique will be discussed to provide practical guidance for choosing the proper analyses.  Finally, I will discuss what characterization should be performed prior to thermal analyses and introduce the “health check” tests which MCL routinely performs to ensure our instrumentation is operating properly. 

Dean Anderson
After Café: Evaluating Residual Stress and Strain States Using X-ray Diffraction Techniques

X-ray diffraction (XRD) techniques provide an attractive, nondestructive method to determine residual stresses by measuring atomic plane spacings in diffracting volumes and relating them to strain using the sin^2(psi) technique. This presentation will review the theory behind these calculations, identifying characteristics to look for during data analysis, a review of the advantages and limitations surrounding different experimental geometries, such as Bragg-Brentano and Grazing Incidence X-ray Diffraction (GIXRD), and an overview of MCL X-ray capabilities.  I will conclude with a short discussion about identifying when synchrotron x-ray capabilities may be appropriate for your specific experimental conditions. 

Taylor S. Wood – PhD Candidate, Materials Science and Engineering 

After Café: New Ways to Characterize Biological Samples using Scanning Transmission Electron Microscopy and Liquid Atomic Force Microscopy

Biological samples are often difficult to image due to their thickness, low contrast, and native hydrated state. We will discuss two different techniques available for analyzing these types of samples in Penn State's Material Characterization Lab, including scanning transmission electron microscopy (STEM) with energy dispersive spectroscopy (EDS), and liquid atomic force microscopy (AFM). Using a TEM with STEM-EDS capabilities, we can quickly acquire elemental maps at resolutions of less than 1 nm and sensitivities of less than one atomic percent. This provides many opportunities to answer important scientific questions related to the presence of metal atoms or other biologically relevant elements such as S, P, Ca, etc. in cells and biological structures in general. The other benefit of STEM imaging is the ability to image thicker samples with enhanced mass-thickness contrast as compared to TEM. This also makes the technique ideal for thick biological samples and removes some of the need for heavy metal staining in fixed samples. STEM imaging under cryo conditions or in liquids is also possible but poses significant challenges at high resolutions. However, we can use an AFM in liquid mode to capture the surface topography of biological samples with sub-nanometer-scale resolution in their native hydrated state. Since biological samples typically contain ~80 % water, removing water from or freezing a material can significantly alter its chemistry and structure and affect any analysis performed on that material. The capability of liquid AFM includes high-resolution imaging in fluid/hydrated samples, nanomechanical mapping, nanoindentation, high-speed AFM to molecular movements, and functionalized tip for molecular interaction. 

Jennifer Gray, Sarah Kiemle
After Café: Irreproducible or Low-Quality Data? How’s Your Prep?

Quality materials characterization always begins with proper sample preparation.  All too often individuals rush to analyze a sample without considering how its intrinsic state will influence results.  Considering sample roughness, thickness, critical feature size, or potential sources of contamination are just a few questions to ponder before jumping on that fancy analytical instrument.  The MCL has revamped its sample preparation laboratory with new expertise, equipment, and procedures.  I will highlight how to get started using this lab and provide general tips & tricks to improve the rigor and reproducibility of your work.

Bob Hengstebeck
After Café: Infrared Emission Characterization: Practical Approaches and Applications

Measuring the thermally emitted radiation of coatings, devices, and other materials has become an increasingly important topic as coatings are being applied to manage increasing heat loads on our infrastructure and as devices are pushed to higher limits. Characterizing the emissive property is relevant for developing technologies in energy conversion, imaging, and thermal management.  The MCL has recently developed methods to quantify the wavelength and intensity of the thermally emitted radiation from various samples ranging in size from 10’s of microns to the macro-scale. 

Tawanda Zimudzi, Linxiao Zhu