Seminars

Abstract: We have theoretically investigated the effect of the chemical bonding structure on mean-squared optical anisotropy of chains by statistical mechanics for a certain class of macromolecules by introducing different molecular groups and atomic species at various positions on the backbone with a motivation to reduce the birefringence. We present results of recent calculations on some real systems as well as some preliminary studies on model bead-spring chains (homopolymers).

Abstract : Tera Hertz a narrow band lying between FAR-IR and Microwaves (5 – 125 wave numbers) is proving to be a powerful tool for imaging and also obtain spectroscopic data which can be put to use in various ways. The key areas where these properties are currently used include Security/Defence (explosives and drug detection) Pharmaceutical (Polymorphism homogeneity tablet inspection High resolution gas analysis Medical Imaging - Tissue analysis for cancer detection dentistry Biometry Electronics Semiconductors and Paints and Coating (Defect analysis and layer thickness measurements etc).

Abstract: Immiscible homopolymers are often blended together to achieve properties not possible with a single homopolymer. We will describe the effect of interfacial modifiers on the structure and flow properties of polymer blends. We will also discuss attempts to transplant existing strategies of structure control from small-molecule two-phase systems e.g. mayonnaise to immiscible polymer blends. As a first example of interfacial modifiers we will consider block copolymers which are often used to promote blending of immiscible polymers.

Abstract: A combined x-ray photon correlation spectroscopy and rheometry study is reported of moderately concentrated suspensions of silica colloids that form a gel on cooling. The suspensions are comprised of silica colloids 45 nm in diameter coated with octadecyl-hydrocarbon chains in decalin at colloidal volume fractions ranging from 0.20 to 0.43. During gel formation the suspensions acquire a shear modulus that increases with time while the thermal motion of the colloids becomes localized over an increasingly restricted range.

Abstract: The research for development of new materials and evaluation of these materials for potential applications in environmental pollution control is a growing subject of research. The recent development in nanoscience surface chemistry and environmental engineering has a substantial influence in the paving the way for development of nanoscale materials adsorbents porous materials nano-catalyst photocatalytic materials coagulant formulations etc. There is always a scope for development of new materials through modifications and understanding of the surface phenomenon.

Abstract: Arsenic contamination has become a grave problem to mankind in various parts of the world. Several places in India specially gangetic plains in West Bengal and plains of Bangladesh are badly hit. The arsenic concentration in the groundwater can be as high as 700 to 900 ppb whereas WHO regulation is 10 ppb in the drinking water. The government policy is digging deeper tubewells and extracting the groundwater and put that in public distribution system. This aggravates the problem further making future generation at stake.

Abstract Pressure driven membrane based processes are used frequently nowadays.The applications range from effluent treatment to production of purified biotechnological products. Appropriate modeling of such processes is required for better understanding of the underlying principles as well as for easy scale up. Based on the complexities involved these models are categorized in several important groups. In this talk various models and their appropriateness have been discussed.

Abstract: There is a strong focus on fire and explosion safety on facilities handling highly flammable gases and liquids. High equipment density coupled with storage under pressure and many potential leakage and ignition sources contribute to a high explosion risk. Serious accidents that have occurred both offshore and onshore in the past demonstrate the necessity of this strong emphasis on safety. The seminar starts by briefly discussing the combustion mechanisms important during explosions and the factors affecting these mechanisms.

Abstract: Metabolic engineering and synthetic biology are important emerging areas in biology. Metabolic engineering deals with performing genetic alterations to a wild type strain i.e. a strain as it exists in nature such that the mutant can overproduce some metabolite of commercial interest. Synthetic biology deals with the construction of artificial biological systems for the purpose of studying important biological processes or for the purpose of strain improvement. A common aim in both the disciplines is strain improvement which is the focus of this work.

Abstract: Membrane is a phase that allows selective transport of a species through them resulting to physical separation of a species. Polymers are one of the key components to prepare these membranes. Polymeric membranes have numerous applications starting from water treatment to various industrial applications ranging from pharmaceuticals to food processing and treatment of various industrial wastewater. This talk demonstrates how casting conditions would result to membranes of various characteristics.