Abstract

Particles in sub-micrometer and nanometer diameters are often encountered in various industrial systems using aerosol reactors for producing a wide variety of particulate commodities such as carbon black and TiO2 nanopowders; and in many other systems where a large quantity of “undesirable” particles are produced, such as, municipal waste incinerators, welding systems, diesel engine and aircraft exhausts. Experimental tools to produce, characterize and manipulate sub-micrometer particles (i.e., with the particle size less than 1000 nm) play an important role in studying modern particle science and engineering. This talk will share with you the development and applications of these tools, including a nanometer differential mobility analyzer (Nano-DMA) to size/classify nanoparticles with the diameters ranging from 1 to 150 nm; a fast-scan electrical nanoparticle sizer having the high resolution and fast response capability to measure particle size distributions in jet and diesel engine exhausts; a multistage DMA capable of classifying monodisperse particles of different sizes at the same time; coaxial flow cyclone for collecting nanoparticles; and whispering gallery mode resonator for sizing particles. The more recent development of miniature sizers enabling to measure fine and ultrafine particles in the near-surface distribution and/or at the personal level will be also discussed. In addition, various electrospray techniques to produce monodisperse composite particles for environmental, biomedical, pharmaceutical and toxicity studies will be presented.

Biography

Daren (Da-Ren) Chen, Ph.D., is now Floyd D. Gottwald Sr. Endowed Chair Professor in Mechanical and Nuclear Engineering, Virginia Commonwealth University (VCU), USA. He received his PhD. from Particle Technology Laboratory, University of Minnesota, USA (1997). Prior to joining VCU, he had working as a faculty in Washington University in St. Louis for 12 years, in which he was promoted from assistant professor to full professor. Professor Chen is the principal investigator and inventor of electrospray monodisperse particle generator, nanometer differential mobility analyzer (nano-DMA), high-through nanoparticle charger, fast-scan electrical aerosol sizer, personal particle monitors, and many other particle processing tools. He has published more than 200 peer-viewed papers. He holds 21 US and 4 international patents in aerosol particle technology. He receives Sheldon K. Friedlander Award (1997), Smoluchowski Award (2002), Kenneth Whitby award (2005) and Benjamin Liu Award (2012) for his significant contribution in nanoparticle instrumentation and experimental techniques. He has intensive experience on particle sampling and characterization, particle instrumentation, atmospheric aerosol, filtration and separation, micro-contamination control in semiconductor processing, health effect of particles, nanotoxicity, and particle synthesis/generation for energy, pharmaceutical and biomedical applications.