Professor of Chemical Engineering
Director, Bioengineering and Life Sciences Program
My professional interest is in the application of mechanics and physics to the understanding and design of materials, particularly at the micro and nano-scale. My background in is theoretical and computational mechanics, but from the time of my Ph.D. dissertation work, I have been deeply connected to and interested in materials science and physics. My choice of working in the environment of materials science and chemistry at DuPont was based essentially on my interest in connecting theory and computation to predictions that would be useful to a materials designer. I would add that the only way I have found of doing this well is to have significant personal involvement in materials development and experimentation. While my strength is in theory and predictive modeling, I have always maintained a strong experimental program. I am keenly aware that the word ëpredictioní ranges from simple indication of direction to providing detailed and quantitative answers. I have been fortunate to be able to work over the entire spectrum.
As an example of the former, I would offer my recent interest and work on bio-molecule binding to carbon nanotubes. The group I lead at DuPont is pioneering the study of interactions between peptides/DNA and carbon nanotubes. We have discovered short peptide and ssDNA sequences that bind selectively to carbon nanotubes. The consequences of this development range from use of carbon nanotubes in nanoelectronics, medical and sensor applications, to potential bio-molecule based techniques for their separation. In addition to leading the program, I have worked on computational analyses of molecule conformations and the thermodynamics of binding; these have played a major role in these discoveries.
As an example of theory and computation providing detailed quantitative answers, I would offer my work on developing materials-properties-based design of glass/polymer laminates. These materials are ubiquitous ñ every automotive glass windshield is laminated, as are many windows in buildings. Our computational model for the first-cracking response of glass/polymer laminates is now accurate enough to form the basis for ASTM (and, soon, ISO) standards for design. We have also developed methods that will lead to quantitative computational design of laminate properties post-glass fracture.
These two examples show that my research interests are very broad, but ultimately tied to bringing computational mechanics and physics to materials design problems. I have worked on problems that require physics over a wide range of scales, starting with quantum mechanical modeling of electron transport, to microstructural and macroscopic scales. My personal interests are highly problem and physics-focused. The current explosive interest in materials design at the meso-scopic scale lies directly in the sphere of my experience and interest. I have worked, for example, on bringing the continuum scale down to the molecular level by developing cohesive elements for fracture and surface force models for nano-particle interactions.
Another example is the previously mentioned study of bio-molecule/substrate interactions from the molecular mechanics point of view. Perhaps by the influence of working at a company where the research site is called the ìExperimental Stationî, I have been persuaded that at least in the disciplines of Materials Science, Chemistry, and Bio-chemistry/materials, theory divorced from close connection to day-to-day experimentation soon turns slow and barren. Nevertheless, when theory and computation accepts the burdensome and confusing complexity of working closely with the intuitive experimentalist, it always results in incisive discoveries and advances. Fed by such rationale, theorists can return to make their longer-term developments on a truly sound foundation.
Undoubtedly, the converging interests of bio-chemists, materials chemists, physicists, mechanicians, and materials scientist are opening up the most exciting new vistas today in science and technology. I am extremely fortunate to be participating in this personally. This is both by leading a group at DuPont which includes biologists, materials scientists, chemist, and engineers, and by contributions to theoretical and computational modeling for its problems. Advances in this endeavor will be made by interdisciplinary groups. Separate disciplines must retain their structure because they bring quite different historical approaches; however, the speed with which good interdisciplinary research programs can advance is unrivalled. Having developed a large interdisciplinary research group at DuPont, and seeing its efficacy, it would be my strong intention and desire to develop and participate in similar efforts at Lehigh.
I derive strong personal satisfaction from teaching and working with students. Because of this, I have always maintained strong collaborations with academic colleagues and have participated closely in developing the Ph.D. dissertations of many students. I have a strong personal interest in investigating novel approaches to education and exposition, particularly when it comes to presentation of principles and content. With others, I have explored what multimedia can contribute. My opinion is that for subjects rich in visual content, it offers a remarkably strong addendum to text and graphics-based learning.
Polymers and Materials.
Metal and ceramic powder deformation. Polymer sintering. Ultrasonic welding of polymers. Processing and mechanical properties of ceramics. Composites.
Mechanical properties of glass-polymer laminates and their use in automotive and architectural applications.
Biological and chemical routes to nanoelectronic devices. Use of biological molecules for the manipulation o