01519nas a2200193   4500008004100000022001400041245012000055210006900175260008000244300001400324490000700338520073200345100001801077700002001095700002501115700002201140700003301162856013001195       2006                        eng d  a0957-448400aOptically transparent magnetic nanocomposites based on encapsulated Fe3O4 nanoparticles in a sol-gel silica network0 aOptically transparent magnetic nanocomposites based on encapsula  aDIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcNOV  a5565-55720 v173 a<p>Composite Fe3O4-SiO2 materials were prepared by the sol-gel method with tetraethoxysilane and aqueous-based Fe3O4 ferrofluids as precursors. The monoliths obtained were crack free and showed both optical and magnetic properties. The structural properties were determined by infrared spectroscopy, x-ray diffractometry and transmission electron microscopy. Fe3O4 particles of 20 nm size lie within the pores of the matrix without any strong Si-O-Fe bonding. The well established silica network provides effective confinement to these nanoparticles. The composites were transparent in the 600-800 nm regime and the field dependent magnetization curves suggest that the composite exhibits superparamagnetic characteristics.</p>1 aThomas, Senoy1 aSakthikumar, D.1 aJoy, Pattayil, Alias1 aYoshida, Yasuhiko1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/optically-transparent-magnetic-nanocomposites-based-encapsulated-fe3o4-nanoparticles-sol-001510nas a2200217   4500008004100000022001400041245005400055210005300109260010300162300001000265490000700275520078400282100001401066700001601080700002501096700001801121700001501139700001701154700003301171856008801204       2010                        eng d  a0295-507500aColossal thermoelectric power in Gd-Sr manganites0 aColossal thermoelectric power in GdSr manganites  a6 RUE DES FRERES LUMIERE, MULHOUSE, 68200, FRANCEbEPL ASSOCIATION, EUROPEAN PHYSICAL SOCIETYcJUL  a170080 v913 a<p>Manganites belonging to the series Gd(1-x)Sr(x)MnO(3) (x=0.3, 0.4 and 0.5) were prepared by wet solid-state reaction and their thermoelectric power was evaluated. Thermoelectric power measurements revealed a peak value at similar to 40 K. All the samples exhibited a colossal thermopower at similar to 40K and in that Gd(0.5)Sr(0.5)MnO(3) exhibited a maximum value of similar to 35 V/K, which is the largest reported for these class of materials at this temperature. Temperature-dependent magnetisation measurements showed that the samples exhibit a phase transition from paramagnetic to spin-glass-like state at these temperatures. Plausible mechanisms responsible for the observed colossal thermoelectric power in Gd-Sr manganites are discussed. Copyright (C) EPLA, 2010</p>1 aSagar, S.1 aGanesan, V.1 aJoy, Pattayil, Alias1 aThomas, Senoy1 aLiebig, A.1 aAlbrecht, M.1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/colossal-thermoelectric-power-gd-sr-manganites-0