Three-Phase Slurry Reactors
Professor Ahmadi is collaborating with scientists at the Department of Energy in modeling a three-phase slurry reactor for synthetic liquid fuel production from coal. One main objective is to develop an advanced computational capability for predicting the transport and processing of three-phase (liquid - gas - solid) slurry reactors. The specific objective is to develop an accurate and reliable computational model for predicting the process parameters using the extended thermodynamically consistent anisotropic theories of multiphase flows
The primary goal of Professor Ahmadi's project is to provide a fundamental understanding of flow conditions of hydrate dissociation products in consolidated and unconsolidated sediment. He and his group will develop semi-analytical computational models to be used as tools for safety related issues. These include predicting the rate of natural gas pressure buildup during drilling in a hydrate reservoir, the nature of gas and water flows in the reservoir after hydrate dissociation, and the potential for sea floor instability. Availability of such an understanding, detailed experimental data and a computational tool are crucial to the future development of technology for economical and safe natural gas production from hydrates in the 21st Century.
Professor Ahmadi is studying the process of hot-gas filtration for applications to clean coal technology. In this project, the performance of ceramic candle-filters for hot-gas cleaning is being studied. Research results show that small particles (less than a micron) deposit rather uniformly in the filter vessel, while the larger particles deposit non-uniformly. This work has significant implications in designing future industrial scale hot-gas cleaning systems.
Professor Ahmadi and his students, along with Dr. Fan of Xerox, are studying electrohydrodynamic flows during corona discharge in an electrophotographic machine (e.g., printers and copiers). They developed a computational model for analyzing gas electrohydrodynamic flows and the transport and deposition of charged toner particles in the presence of a strong electric field. They showed that electrohydrodynamics could strongly affect the transport and deposition of small particles in corona devices.
In addition, Professor Ahmadi is collaborating with Dr. Sadasivan of Kodak on a project about the aerodynamic focusing of nanoparticle beams.
Novel Methods for Liposome Synthesis
Professor Yuzhuo Li and his graduate students, Nicole Heldt and Fadwa Odeh , are exploring new methods for the preparation of liposome with controlled particle size and size distribution. The pharmaceutical industry utilizes liposomes for a variety of applications such as drug delivery and diagnostic imaging. For drug delivery systems both polymer stabilized liposome systems (PSLS) and non-polymer stabilized ( conventional ) liposome systems (NPSLS) are beneficial. In collaboration with Adjunct Professor Robert Laughlin and Research Associate Professor Chris Brancewicz, Li's group is systematically investigating the effect of a hydrotrope on the phase behavior of lipids and its impact on the liposome properties. As a world renowned scientist in phase science, Professor Robert Laughlin, brought a tremendous wealth of expertise to the Chemistry Department and CAMP at Clarkson. His applied physical lecture series is available for viewing at http://media.clarkson.edu . The goal of this research is to develop an optimized liposome system for drug delivery and medical diagnostic applications.
Professor Anja Mueller, of Clarkson University's Department of Chemistry, is carrying out research that makes use of polymers in biomedical work. Her postdoctoral research was on liposomes as drug delivery agents. It included the characterization of controlled release upon a light signal, liposome fusion with membranes, and characterization of the behavior of liposomes in a cell culture. Professor Mueller's current and future research projects include the development of a biological fuel cell for medical sensors, synthesis of hydrophilic polymers with enzymes and their surface characterization for the development of a heart valve coating and other biomedical applications. In addition she will investigate the use of polymers for biosensors and waste water treatment. Professor Mueller has a Provisional Patent 60/347,012 (Anja Mueller and Maciej Markowski: "Low Thrombogenic Coating for Intravascular Devices."). Her recent publication is : Mueller, A. and O'Brien, D.F., "Polymerization of Mesophases of Hydrated Amphiphiles," Chemical Reviews , 102, 727 (2002).
Professor Sergey Minko, the Egon Matijevic' Chair Professor of Chemistry, is an expert in colloid science and has done extensive work involving "Smart Responsive Functional Materials Based on Self Assembly in Polymer and Colloidal Systems." His CAMP-related research interests include smart/responsive polymer materials, smart colloids, nanostructured thin polymer films, nanotemplates and nanomembranes, formation of nanowires and nanoparticles, adhesion, wetting, adsorption regulation, single molecule devices, and combinatorial methods in material science.
Research in Professor Devon Shipp's laboratories centers on novel polymerization techniques and new polymer materials. Over the past year a number of new developments have taken place in these areas.
The synthesis of polymer-silicate nanocomposites, where the polymers have well-defined molecular weights and molecular weight distributions (i.e. predictable average molecular weights and low polydispersities) has been achieved using three variations of living radical polymerization, viz. atom transfer radical polymerization (ATRP), nitroxide-mediated polymerization (NMP) and reversible addition-fragmentation chain transfer (RAFT) polymerization. Nanocomposites containing homopolymers of styrene, n-butyl acrylate (BA) and methyl methacrylate (MMA) have been produced using montmorillonite as the silicate material. This is the first work in which RAFT has been used to produce polymer-silicate nanocomposites.
Block copolymer nanocomposites of polystyrene-block-poly(MMA) and polystyrene-block-poly(BA) have been produced using ATRP. These block copolymer materials represent the first successful production of block copolymer-silicate nanocomposites using living radical polymerization. These are expected to exhibit interesting phase separation behavior, in addition to the well-documented improvement in physical properties such as modulus, gas barrier properties, impact strength, and lighter weights. The work on block copolymer nanocomposites has been recently published (Chem. Mater. 2003, 15, 2693-2695).
The synthesis of polymer-silicate nanocomposites via NMP and RAFT utilized silicate layers that had been modified by a quaternary ammonium salt compound containing a monomer moiety. NMP of styrene proceeded in the expected manner for a living radical polymerization. TEM and x-ray diffraction (XRD) of the product material clearly showed a significant degree of exfoliation. RAFT polymerization of MMA in the presence of the monomer-modified silicate also resulted in well-controlled molecular weights and low polydispersities.
Two other projects in Professor Shipp's laboratory that utilize the group's expertise in polymer synthesis are (1) the synthesis of polymer modified TiO2 particles for potential use in photovoltaic cells, and (2) the synthesis of light-harvesting polymers exhibiting stimuli responsive behavior.