Seminars

The design and control of microstructural evolution is the key to the processing of materials ranging from semiconductors to metals to polymers. In the case of crystalline silicon and its alloys which are commonly used in the microelectronics industry nucleation and aggregation of point defects and impurities are responsible for the formation of a wide variety of nano- and microstructures. While these microstructures often are detrimental to electronic devices they can also be useful if their formation can be precisely controlled.

Abstract  First-principles models at electronic and atomic scales offer exciting opportunities for rationally designing novel chemical engineering technologies with a broad range of applications. They can accurately capture the underlying transport chemistry and thermodynamics of many complex physical systems. However the use of first-principles methods for design is limited by two challenges which renders these methods computationally intractable - a theme that is found to recur in several systems.

Abstract : I will be talking about concept of Lipid-Biorefinery that I have worked upon and developed along the course of my PhD studies here at Technical University of Denmark. I will be presenting my relevant work done during course of PhD studies in context of the lipid-based biorefinery and its potentials in Indian scenario.

Abstract: Oxidized phospholipids (OXPLs) have recently been implicated in the biogenesis of several diseases including cancer and heart ailments. The biophysical characteristics of OXPLs were investigated using Molecular Dynamics Simulations. The short polar oxidized acyl chains of OXPLs could reverse orientation in lipid bilayers thus presenting reactive functional groups to the lipid interface. Such chain reversal is likely to exert a profound influence on the structure and dynamics of biological membranes and on membrane-associated biological processes.

Abstract : The increase of Greenhouse Gas (GHG) predominantly CO2 levels in the atmosphere has caused worldwide concerns of potential global climate change among international organizations industry leaders governments educational institutes and scientists. The scientific evidence is unequivocal that climate change is occurring and human activity including the increasing energy demand and dependence on fossil fuels is a contributing factor. Business as usual GHG emissions will lead to greater warming and climate impacts.

Abstract: My research with students and collaborators has focused on the observation and when possible quantitative modeling of molecular assembly. I will describe chemical engineering approaches to two such industrial processes. First with H. Ted Davis several students and postdoctoral associates have developed new insights into surfactant self-assembly mechanisms and their potential role in advanced material fabrication. Such processes are being imaged with cryo-Transmission Electron Microscopy and modeled using coarse-grained molecular simulation. Second with L. E.

The large surface area of nanoparticles can greatly increase the dissolution rate of hydrophobic drugs. Moreover nanoscale carriers can inhibit the uptake of drug particles by the reticuloendothelial system during circulation permitting enough time for particles to localize in the leaky vasculature of tumors. We use impingement mixing and high supersaturating to create 100 nm particles via rapid precipitation. Particles are protected via block copolymers which co precipitate or are formed by fast coupling reaction during mixing.

Research in nanoscale science and engineering has been primarily directed towards the design and manufacturing of (a) materials with passive nanostructures (e.g. nanostructured coatings dispersion of nanoparticles and bulk nanostructured metals polymers and ceramics) and (b) active devices with nanostructured materials (e.g. transistors amplifiers targeted drugs and delivery systems actuators and adaptive structures). Research on the design fabrication and operation of integrated “nanoscale factories” i.e.

Pressure driven miscible flow focusing on the displacement of a highly viscous fluid by a less viscous one is studied via direct numerical simulation and linear stability analysis. The flow dynamics are governed by the continuity and Navier-Stokes equations coupled to a convective diffusion equation for the concentration of the more viscous fluid through a concentration dependent viscosity and density.

Pressurized fluids (i.e. sub- and super-critical fluids) are versatile agents for the processing of renewable agricultural and forestry materials and can be used in both the extraction and/or reaction modes. Utilizing either or both supercritical carbon dioxide (SC-CO2) and pressurized water i.e. subcritical water (sub-H2O)) provides a universal “green” processing platform that is compatible for producing food and nutritional extracts as well as fuel feed stocks such as bioethanol and biomethane.