Indian Institute of Technology Guwahati

About: Indian Institute of Technology Guwahati is a education organization based out in Guwahati, Assam, India. It is known for research contribution in the topics: Catalysis & Computer science. The organization has 6933 authors who have published 17102 publications receiving 257351 citations.

Effect of Geocell Type on Load-Carrying Mechanisms of Geocell-Reinforced Sand Foundations

Abstract: In this study, a series of model tests has been carried out to develop an understanding of the influence of the geocell material on the load-carrying mechanism of the geocell-reinforced sand foundations under strip loading. Geocells of different types were prepared using geogrids of different types. The parameters studied are as follows: the footing load-settlement response, deformation on the fill surface, strain in the geocell, pressure transmitted to the subgrade soil underlying the geocell mattress, and load dispersion in the geocell mattress. The test results indicate that the strength, stiffness, aperture opening size, and orientation of the rib of the geocell material influence the performance of the reinforced-sand foundation bed. Geocells made of geogrids of higher strength, relatively smaller size aperture opening, and ribs of orthogonal orientation give better performance improvement.

Influence of thermal oxidation on surface and thermo-mechanical properties of polyethylene

Abstract: Blown low density polyethylene (LDPE) films added with oxo-biodegradable additive containing pro-oxidant were subjected to thermo-oxidation in an oven at 70 °C for varying time periods The changes in mechanical and surface properties were studied using tensile strength, elongation at break, wettability, surface morphology using SEM, surface topology by AFM, functional groups by FTIR spectroscopy, absorbance spectra by UV-Vis spectroscopy The thermally aged films with pro-oxidant additive added polyethylene (PE) exhibited a higher level of oxidation as revealed by increase in their carbonyl index than the pristine PE In addition to it, the DSC melting behavior showed a slight increase in crystallinity (%C) and melting temperature (Tm) of the polymer containing oxo-biodegradable additive The SEM micrograph reveals the increase in the size of cracks and grooves, according to the increase in the concentration of pro-oxidant additive The surface roughness also supports the same through AFM image The increase in the wettability and surface free energy of the thermally aged samples were attributed to the formation of hydrophilic groups on the polymer surface by thermo-oxidation The pro-oxidant additive offers a new insight into the thermo-oxidation strategy for PE and can be widely used in packaging industry

A new fluorogenic probe for solution and intra-cellular sensing of trivalent cations in model human cells

Abstract: A new imidazole functionalized anthracene based Schiff base (L) was synthesized and it's selective colorimetric as well as fluorescence responses to trivalent metal cations (Al3+, Fe3+ and Cr3+) over a variety of divalent and monovalent metal cations in 1:1 methanol–water mixed solvent and in live HeLa cells were demonstrated. These selective colorimetric and fluorescence responses were explained as a consequence of protonation of L, where the lower Ksp values of M3+ (Al3+, Fe3+ and Cr3+) facilitated the generation of H+ through hydrolysis. This fluorogenic behavior of the ligand L was further confirmed by theoretical calculations.

Catalytic ozonation of dye in a microbubble system: Hydroxyl radical contribution and effect of salt

Abstract: Catalytic ozonation using metal ions is a promising method to enhance the hydroxyl radical generation from ozone. In this study, four common metal ions i.e., Fe(II), Fe(III), Mn(II) and Cu(II) were used as the catalyst in a microbubble reactor. The metal ions increased the decolorization efficiency of the azo dye, Congo Red (CR). The combined use of metal ion and microbubble increased the effective factor to a good extent. Based on the pseudo-first-order reaction rate constant k (min−1), O3 + Cu(III) showed higher value for both with and without microbubbles at acidic pH. The performance of the metal catalyst on the decolorization of CR followed an order Fe(III) < Fe(II) < Mn(II) < Cu(II). The effect of pH, metal ion concentration on the dye oxidation, and the presence of NaCl and CaCO3 were also studied. The pCBA was used as the radical probe to calculate the hydroxyl radical concentration by using an indirect method. From the depletion rate of pCBA it was observed that the generation of hydroxyl radical was more by the use of Cu(II) and the trend was Fe(III) < Fe(II) < Mn(II) < Cu(II). The removal of TOC followed the same order too.