Beginning scientists receive presidential awards
Carlos Rinaldi, Associate Professor in the Department of Chemical Engineering at the University of Puerto Rico, Mayagüez Campus, was recognized for his research into the response of suspensions of magnetic nanoparticles —minuscule magnets dispersed in a fluid medium— to time varying magnetic fields.
"There are novel phenomena you can observe in the interplay between magnetic forces and viscous forces," noted Rinaldi.
These include the random motion of the small particles in response to collisions with the surrounding fluid molecules.
When time varying magnetic fields, such as oscillating or rotating fields, are applied, the tiny magnetic dipoles tend to track the applied field. Due to the competition between magnetic torques and viscous drag, there is a lag between the applied field and the average magnetization of the suspension. Rinaldi's work has allowed a precise quantitative description of these and other phenomena. It also facilitates the development of novel applications of magnetic nanoparticles in time-varying magnetic fields, such as magnetic nanoparticle based sensors and magnetic fluid hyperthermia, a form of cancer treatment currently under investigation.
Rinaldi is deeply committed to the recruitment and retention of students from underrepresented groups in engineering. He has served as the undergraduate research advisor to 39 Hispanic students, 27 of whom are female. He also regularly advises students from UPR-Mayaguez on applying to summer research programs, graduate school and national fellowship competitions.
Chemical engineer Carlos Rinaldi holds a beaker with oil based ferrofluid (a suspension of magnetic nanoparticles in an oil carrier fluid) with a permanent magnet underneath. The ferrofluid displays the so-called normal field instability, characterized by spikes of fluid following the local magnetic field direction. Rinaldi's work has importance for applications in nanobiosensors and in magnetic fluid hyperthermia for cancer treatment.
Credit: Sindia M. Rivera-Jiménez
The 2006 PECASE awardees standing in the White House with United States President George W. Bush. Dr. Carlos Rinaldi, contributing scientist to IFN, stands seventh from left-to-right on the top row.
Dr. Carlos Rinaldi (center) with Dr. John H. Marburger (Director of the Office of Science and Technology Policy, left) and Dr. Arden Bement (NSF Director, right) during the 2006 PECASE award ceremony.
