02072nas a2200241   4500008004100000022001400041245012100055210006900176260007300245300001200318490000800330520118300338653001801521653002101539653001501560653000901575100002101584700002001605700002501625700002101650700003301671856012601704       2008                        eng d  a0304-885300aEnhanced shape anisotropy and magneto-optical birefringence by high energy ball milling in NixFe1-xFe2O4 ferrofluids0 aEnhanced shape anisotropy and magnetooptical birefringence by hi  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR  a815-8200 v3203 a<p>Ferrofluids belonging to the series NixFe1-xFe2O4 were synthesised by two different procedures-one by standard co-precipitation techniques, the other by co-precipitation for synthesis of particles and dispersion aided by high-energy ball milling with a view to understand the effect of strain and size anisotropy on the magneto-optical properties of ferrofluids. The birefringence measurements were carried out using a standard ellipsometer. The birefringence signal obtained for chemically synthesised samples was satisfactorily fitted to the standard second Langevin function. The ball-milled ferrofluids showed a deviation and their birefringence was enhanced by an order. This large enhancement in the birefringence value cannot be attributed to the increase in grain size of the samples, considering that the grain sizes of sample synthesised by both modes are comparable; instead, it can be attributed to the lattice strain-induced shape anisotropy(oblation) arising from the high-energy ball-milling process. Thus magnetic-optical (MO) signals can be tuned by ball-milling process, which can find potential applications. (C) 2007 Elsevier B.V. All rights reserved.</p>10abirefringence10aCo-precipitation10aferrofluid10aHEBM1 aNair, Swapna, S.1 aXavier, Francis1 aJoy, Pattayil, Alias1 aKulkarni, S., D.1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/enhanced-shape-anisotropy-and-magneto-optical-birefringence-high-energy-ball-milling-002816nas a2200217   4500008004100000022001400041245011000055210006900165260000800234300001400242490000700256520204500263653001802308653003402326653001702360653002602377100001902403700002002422700002702442856012902469       2020                        eng d  a0969-023900aMicrostructural differences between Viscose and Lyocell revealed by in-situ studies of wet and dry fibers0 aMicrostructural differences between Viscose and Lyocell revealed  cFEB  a1195-12060 v273 a<p>Regenerated cellulose fibers manufactured using Lyocell and Viscose processes exhibit differences in their structural response to mechanical deformation. Here, we study the effect of stretching and stress relaxation on the orientation of crystal and amorphous phases. Our results show that on stretching, orientation in both crystal and amorphous phases increases linearly with strain, correlating with the increase in stress and with the stretching of the crystalline unit cell along the c-axis. On holding after stretching to a particular strain, the stress relaxes logarithmically in time, correlating with a decrease in the strain along the c-axis of the crystal unit cell. The stress relaxation is also correlated with a logarithmic increase in amorphous orientation, while crystalline orientation stays constant. We attribute the stress development during stretching to deformation of the crystal unit cell, while crystal reorientation in the fiber direction results in increase in the crystalline orientation parameter. On holding the fiber at a fixed total strain, the stress relaxes as strain is transferred from crystal to amorphous regions. Thus, the strain on the unit cell c-axis decreases and amorphous orientation increases. There are quantitative differences between the rate of increase in amorphous phase orientation during stress relaxation for Lyocell and Viscose fibers. For dry fibers, Lyocell shows a slower increase in orientation during stress relaxation. On wetting the fibers, their structural response changes qualitatively. We combine wide angle x ray diffraction and birefringence experiments with our model to infer that that on stretching the wet fiber, the crystalline phase is neither strained nor oriented. However, orientation develops in the amorphous phase. During stress relaxation in wet condition, Lyocell fibers shows a faster increase in amorphous orientation than Viscose fibers, in line with the comparison of relaxation time spectra for wet Viscose and Lyocell fibers. Graphic abstract</p>
10abirefringence10aCrystal-amorphous orientation10aIn-situ WAXD10aRegenerated cellulose1 aSharma, Aakash1 aThakre, Shirish1 aKumaraswamy, Guruswamy  uhttps://library.ncl.res.in/content/microstructural-differences-between-viscose-and-lyocell-revealed-situ-studies-wet-and-dry