Laser Induced Breakdown Spectroscopy (LIBS) Research

One of the challenges of monitoring air quality in an industrial environment is making measurements over a range of contaminates quickly enough so worker can react and limit their exposure. A promising technique is Laser Induced Breakdown Spectroscopy (LIBS). LIBS can be used to identify the composition of a specimen through analysis of the atomic and molecular fragment emissions produced from a laser generated plasma. The primary advantages of LIBS are that it does not require sample preparation prior to analysis, can collect information over a wide spectral range with a single measurement and has measurement times less than one second.

The LIBS Lab as Seattle University is studying how LIBS can be used to detect airborne contaminates. In 2015 the lab developed a custom instrument to measure airborne silica in mines (McLaughlin et al 2016). Currently researchers are investigating how LIBS might be also used to measure diesel particulate matter.

Research in the lab is a collaboration between the Department of Chemistry and the Department of Mechanical Engineering. Student’s working the lab perform measurement, analyze LIBS spectral data and build and maintain the custom equipment. The lab is equipped with several lasers and spectrometers, an aerosol chamber for safely collecting and measuring contaminates, particle counters and support equipment.

R. P. McLaughlin, G. S. Mason , A. L. Miller, C. B. Stipe, J. D. Kearns*, M. W. Prier* and J. D. Rarick*, “Note: A portable laser induced breakdown spectroscopy instrument for rapid sampling and analysis of silicon-containing aerosols,” Review of Sci. Instruments. 87, 056103, 2016. * Student Researcher

 

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Computational Study Using DSMC

Direct Simulation Monte Carlo (DSMC) technique has been used in computational studies of designing many MEMS (Microelectromechanical systems) devices. A micropump with a built-in microvalve was designed and studied by Dr. Yen-Lin Han using DSMC simulations. Employing rarefied gas phenomenon of thermal edge flow, this micropump is driven by heating up a thermal bimorph microvalve, which opens up the valve to allow the gas flow at the same time. Preliminary results have demonstrated the feasibility of this design.

Related Publication:

Han, Yen-Lin, Proceedings of IMECE2014-38708, ASME International Mechanical Engineering Congress and Exposition, Montreal, Canada, 2014. (Abstract Accepted)

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Microalgae Processing Research

Several undergraduate students contributed to this research through design and testing of several microalgae processing devices. Their work was published in leading journals and presented at several Algae Biomass Summits, the largest algae conference in the US. The research effort is led by Dr. Shuman.

Recent Publications (undergraduate students underlined)

Journals:

  1. Shuman, T. R., Mason, G., Reeve, D., Schacht, A., Goodrich, A., Napan, K., and Quinn, J. “Low-Energy Input Continuous Flow Rapid Pre-Concentration of Microalgae through Electro-Coagulation-Flocculation” Chemical Engineering Journal, Volume 297, 2016, Pages 97-105
  2. Shuman, T. Rutar, Mason, G., Marsolek, M., Lin, Y., Reeve, D., and Schacht, A. “An Ultra-Low Energy Method for Rapidly Pre-Concentrating Microalgae” Bioresource Technology, Volume 158, April 2014, Pages 217-224

Conferences:

  1. Teodora Rutar Shuman, Ben Loveless, Jeremy Bjelajac, and Peter Griff “Continuous-flow Electro-Coagulation-Flocculation for rapid and ultra-low energy pre-concentration of microalgae”, 2017 Algal Biomass Summit, Salt Lake City, UT, October 29 - November 1, 2017.  
  2. Teodora Rutar Shuman, Anthony Rock, Ben Loveless, and Jeremy Bjelajac, “Continuous-flow method for pre-concentrating microalgae with flow rates up to 5 L/min and energy inputs as low as 0.05 kWh/m3 of processed algal slurry”, 2016 Algal Biomass Summit, Phoenix, AZ, October 25th, 2016.  
  3. Rutar Shuman, T., and Mason, G., “Rapid and Ultra-low Energy-use Pre-Concentrating of Microalgae” 2014 Algae Biomass Summit, San Diego, CA, September 29-October 2, 2014 
  4. Rutar Shuman, T., Lin, Y., Bowman, C., Kurtz, V., Pawlak, G. D., “Microalgal Cell Vitality After Ultra-Low Energy Input Rapid Dewatering Process” 2012 Algae Biomass Summit, Denver, CO, September 24-27, 2012

 

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Small Wind Turbine Aerodynamics

Energy poverty affects over a billion people worldwide; off-grid energy sources such as small wind turbines (SWTs) are one method of addressing this problem. Unlike large-scale turbines, SWTs exist in a unique low Reynolds number flow regime which is not fully understood. Furthermore, technology implementation in developing countries is subject to limited availability of materials, manufacturing techniques, and maintenance scheduling. With the help of a number of undergraduate students, the department continues developing the SU wind tunnel laboratory to experimentally investigate these issues; ultimately better turbines may be designed which are ideally suited for the aerodynamic and economic climate in which they are installed.

 

LIBS Lab

  • Nd:YAG laser (Kigre, MK-367)
  • Spectrometer (AvaSpec-2048-USB2 and Avantes multi-channel spectrometer)
  • Particle Counter (pDR1000)
  • Differential mobility analyzer (TSI model 3071A)
  • Condensation particle counter (TSI model 3025A)
  • Aerosol Chamber (custom built 1m3 chamber)
Dean Quinn awards Dr. Mason the Faculty Innovation Award 
Educational Excellence

Professor Greg Mason wins 2015 Faculty Innovation Award as a leader in applying groundbreaking teaching practices in his classroom. His work has been awarded by the National Science Foundation and published in leading educational journals. Dr. Mason always puts students first!