CAMP Annual Report: Page 9
Professor R. Shankar Subramanian is working on interfacial phenomena and their influence on transport problems, especially on drop motion on a horizontal solid surface.
In collaboration with his students, Professor Subramanian is studying the motion of a liquid drop on a solid surface because of the action of a temperature gradient. Such motion can be important in moving drops from one place to another in microfluidic devices, in condensation heat transfer, and in the removal of debris in inkjet printing. The research program involves experiments on the motion of drops of organic liquids on PDMS-coated glass slides, when subjected to a temperature gradient across the solid surface. The drops move from the warm side of the solid surface to the cooler side, because of the action of thermocapillary flows generated within the drop due to the surface tension gradient on the free surface of the drop, which arises from the temperature gradient. The motion is videotaped and subsequently analyzed to obtain information on the size of the drop, as well as its position. From these data, the velocity of the data is inferred at different temperature gradients, as a function of the size of the drop. A theoretical model developed using lubrication analysis is used to predict this velocity, and comparisons are made between the predicted and observed velocities. Recent measurements on decane drops show reasonable accord between theory and experiment, but the footprints of the drops are deformed from a circle. Efforts are under way to understand the origin of this deformation and predict it.
Novel and Sustainable Concretes
Professor Narayanan Neithalath, of Clarkson's Department of Civil and Environmental Engineering, carries out research related to the development, performance evaluation and prediction, and modeling of novel and sustainable concrete materials. As part of his NSF CAREER grant, he is exploring the material design - material structure -performance relationships for highly porous concretes that have immense potential in storm-water management and tire-pavement interaction noise reduction. Optimizing the pore structure of this sustainable concrete material in order to satisfy the structural and functional needs, and understanding its influence on performance through experimental and modeling techniques are the focuses of this research. Professor Neithalath previously investigated the use of waste glass powder and limestone powder as potential ingredients in concrete with grants from Empire State Development, NYSERDA, and NYSTAR. As a result of this work, he developed techniques to incorporate significant amounts of these waste materials in concrete. Extending his work on partial Portland cement replacement in concretes by waste materials, Professor Neithalath is currently studying the behavior and performance of concretes that contain no Portland cement at all. These novel concretes are proportioned by activating siliceous and aluminous waste materials such as fly ash and ground blast furnace slag. The energy, environmental and economic implications of replacing cement completely in concrete systems with waste or byproduct materials are very significant.
Greening the Cheese Making Process
R3 Fusion Inc., a green engineering company located in Massena, NY, in collaboration with Clarkson University and the Environmental Services Unit of NYS Empire State Development, has built a novel-processing module to help an upstate cheese manufacturer better manage its byproduct. The innovative equipment is able to quickly and cost-effectively separate water from waste whey, thereby allowing for the recovery and reuse of the water and possibly enabling the business to market the dried, organic residual instead of paying for its disposal. See Figure 6. The process system is extremely efficient and provides the opportunity for significant energy savings. R3 Fusion is also pursuing use of the same technology for developing compact and energy-efficient desalination pilot plants, anticipating significant growth in its food and water-based divisions. For additional information, contact Dr. Roshan Jachuck (President of R3 Fusion and a Professor of Clarkson University) at firstname.lastname@example.org.
Figure 6. From left to right: Waste Whey Containing Water, r3 Water Technology, Recovered Water.
Captivated Undergrad Joins Professor Katz's Research Team
During the spring semester of 2009, Kevin MacVittie (photo), now a sophomore at Clarkson University, attended a lecture by Professor Evgeny Katz about Biocomputing, which left such an impression on the first year undergrad that he immediately sought to join the Professor's research team. Kevin MacVittie has been performing research in the group of Professor Evgeny Katz for approximately six months. In this relatively short period of time, Kevin's outstanding initiative and ability to quickly learn scientific concepts has resulted in a paper submitted for publication entitled, Set-Reset Flip-Flop Memory Based on Enzyme Reactions: Towards Memory Systems Controlled by Biochemical Pathways. An enzyme based flip-flop (Figure 5) allows for the integration of chemical actuators with built-in biological memory units. The biocompatibility of such memory units shows promise as the basic elements of future implantable biomedical devices controlled by immediate physiological conditions. In addition to the completion of a research project, Kevin has also presented his results in an oral presentation at the 2009 Summer Symposium on Undergraduate Research Experience (SURE), which demonstrated his exemplary accomplishments. His enthusiasm for research is contagious and inspires other members of Professor Katz's research team with positive energy and fresh ideas. As he carries a double major in Biology and Chemistry along with a minor in mathematics, Kevin values his undergraduate research experience as it prepares him for a future in medical school.
Figure 5. Words encoded using ASCII character codes upon application of different set-reset signals to the enzyme-based flip-flop system. Optical read out of the words "Clarkson" (A) and "University" (B). Color photo of the multi-well reactor with the encoded word "University" (C) and the respective ASCII codes for the used characters (D).