Indian Institute of Technology Bhubaneswar

About: Indian Institute of Technology Bhubaneswar is a education organization based out in Bhubaneswar, India. It is known for research contribution in the topics: Large Hadron Collider & Computer science. The organization has 1185 authors who have published 3132 publications receiving 48832 citations.

A critical review on bubble dynamics parameters influencing boiling heat transfer

Abstract: The rate of heat transfer during boiling is governed by various bubble dynamics parameters such as bubble departure diameter, active nucleation site density, bubble waiting period, bubble growth period, bubble growth rate and bubble departure frequency. The study of bubble dynamics during boiling of liquids over a heated surface is a complex process due to non-linear growth of bubbles. Many studies on bubble dynamics is carried out by both experimentally and numerically. These studies are carried to propose various empirical and semi-empirical correlations for determination of bubble dynamics parameters. In the present paper, a comprehensive review is carried out to compile various correlations proposed for determination of bubble dynamics parameters. The correlation for determination of boiling heat flux or boiling heat transfer coefficient based on these bubble dynamics parameters are reported. This is done to identify important bubble dynamics parameters affecting boiling heat transfer process. Further, factors affecting bubble dynamics parameters such as effect of thermo-physical properties, heat flux, liquid sub-cooling, wall superheat, contact angle, gravity, cavity spacing and pressure are also given to get an insight into the correlation proposed for determinations of bubble dynamics parameters. The present review article proposes the importance of development of generalized boiling heat transfer correlation using bubble dynamics parameters.

A schiff base ligand of coumarin derivative as an ICT-Based fluorescence chemosensor for Al3+

Abstract: We have developed a novel coumarin-based chemosensor H 2 L with ICT character bearing the hydrazone of substituted phenol, synthesized by the condensation of 2-hydroxy-4-methylbenzohydrazide with 3-acetylcoumarin. The fluorescence spectra of the receptor H 2 L demonstrated that the sensor could selectively recognize Al 3+ over other metal ions and the detection limit was found in the micromolar concentration range. Sensing capability of the receptor for Al 3+ was reversible. Cu 2+ complex of H 2 L was structurally characterized which gave the basis for possible structure of Al 3+ complex of H 2 L. The Turn On fluorescence of H 2 L is based on intramolecular charge transfer (ICT), chelation enhanced fluorescence (CHEF) and C N isomerization to serve as fluorescent chemosensor in DMF-water solvent mixture. The receptor H 2 L showed a remarkably red-shifted absorption spectrum in the presence of Al 3+ in DMF. B3LYP-SCRF/6-31G* density functional theory explains the ICT mechanism.