Indian Institute of Technology Indore

About: Indian Institute of Technology Indore is a education organization based out in Indore, Madhya Pradesh, India. It is known for research contribution in the topics: Computer science & Chemistry. The organization has 1606 authors who have published 4803 publications receiving 66500 citations.

Raman spectroscopy for study of interplay between phonon confinement and Fano effect in silicon nanowires

Abstract: A combined effect of doping (type and species) and size on Raman scattering from silicon (Si) nanowires (NWs) has been presented here to study interplay between quantum confinement and Fano effects. The SiNWs prepared from low doping Si wafers show only confinement effect, as evident from the asymmetry in the Raman line-shape, irrespective of the doping type. On the other hand SiNWs prepared from wafer with high doping shows the presence of electron–phonon interaction in addition to the phonon confinement effect as revealed from the presence of asymmetry and antiresonence in the corresponding Raman spectra. This combined effect induces an extra asymmetry in the lower energy side of Raman peak for n-type SiNWs whereas the asymmetry flips from lower energy side to the higher energy side of the Raman peak in p-type SiNWs. Such an interplay can be represented by considering a general Fano-Raman line-shape equation to take care of the combined effect in SiNWs. Copyright © 2015 John Wiley & Sons, Ltd.

Targeted water soluble copper-tetrazolate complexes: interactions with biomolecules and catecholase like activities

Abstract: Two new mononuclear water soluble copper(II) complexes, [Cu{(5-pyrazinyl)tetrazolate}2(1,10-phenanthroline)] 1 and [Cu{(5-pyrazinyl)tetrazolate}(1,10-phenanthroline)2](NO3)0.5(N3)0.5 2, have been synthesized using the metal mediated [2 + 3] cycloaddition reaction between copper bound azide and pyrazinecarbonitrile. The interactions of these copper tetrazolate complexes 1 and 2 with biomolecules like DNA and bovine serum albumin (BSA) are studied and the catecholase like catalytic activity of compound 2 is also explored. Structural determination reveals that both compounds 1 and 2 are octahedral in nature. Screening tests were conducted to quantify the binding ability of complexes (1 and 2) towards DNA and it was revealed that complex 2 has a stronger affinity to bind to CT-DNA. DFT studies indicated that a lower HOMO-LUMO energy gap between the DNA fragment and metal complexes might be the reason for this type of stronger interaction. DNA cleavage activity was explored by gel-electrophoresis and moderate to strong DNA cleavage properties were observed in the presence and absence of co-reagents. Inhibition of cleavage in the presence of sodium azide indicates the propagation of the activity through the production of singlet molecular oxygen. Furthermore enzyme kinetic studies reflect that complex 2 is also effective in mimicking catecholase like activities. An ESI-MS spectral study indicates the probable involvement of dimeric species [(phen)2Cu-(OH)2-Cu(phen)2](2+) in the catalytic cycle.

Strength and Durability Assessment of Expansive Soil Stabilized with Recycled Ash and Natural Fibers

Abstract: This study explored the coupling effect of the recycled ash and natural fibers to control the expansive soil's strength and durability attributes The bottom ash (BA) was used to chemically treat the expansive soil and coir fibers (CF) as reinforcement against tensile cracking The sustainable use of BA and CF to stabilize the expansive soil has been demonstrated by assessing - swelling behavior, mechanical and chemical properties The expansive soil was stabilized with 5%, 10%, 15% and 20% BA and reinforced with 025%, 050% and 100% CF The curing period of 28 days was considered for the stabilization of the soil This study presents individual material's effect to stabilize the expansive soil subgrade and also the coupling effect of both fibers and ash The durability of stabilized expansive soil has been assessed by investigating the mechanical and chemical properties before and after 2nd, 4th, 6th, 8th and 10th freeze–thaw cycles The BA stabilized expansive soil exponentially reduces the upward swelling pressure and controls the plasticity behavior An increase in the percentage of BA has increased the calcite content, pH, and electrical conductivity The unconfined compressive strength and split tensile strength have been increased due to BA and CF The CF reinforced specimens shows less loss in mechanical strength during freeze–thaw cycles and gives higher tensile strength The effective mechanism of BA and CF stabilized expansive soil is discussed in detail The BA and CF can be effectively used to stabilize the expansive soil for the application of road pavements The approach used here to stabilize pavement subgrades is sustainable and will provide economical solutions