01534nas a2200253   4500008004100000022001400041245006500055210006500120260007300185300001400258490000700272520073300279653001301012653002301025653002401048653001101072653001101083653002201094100002101116700001501137700001901152700001301171856009601184       2006                        eng d  a0167-577X00aPhase evolution of NiTiO3 prepared by coprecipitation method0 aPhase evolution of NiTiO3 prepared by coprecipitation method  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL  a1791-17920 v603 a<p>A simple coprecipitation technique was used for the preparation of NiTiO3 powders. Ammonium carbonate solution was added to a solution mixture containing stoichiometric amounts of Ni(NO3)(2) and TiOCl2 to precipitate nickel as carbonate and titanium as hydroxide under basic conditions. The precipitate was calcined at different temperatures ranging from 100 to 800 degrees C and phase evolution of NiTiO3 was investigated by X-ray diffraction (XRD) studies. It is observed that nickel titanate was formed at 750 degrees C. For comparison, NiTiO3 was also prepared by standard ceramic process. Particle size and morphology was studied by transmission electron microscopy (TEM). (c) 2005 Elsevier B.V. All fights reserved.</p>10aCeramics10aChemical synthesis10aElectron microscopy10aNiTiO310aOxides10aX-ray diffraction1 aMurugan, Vadivel1 aSamuel, V.1 aNavale, S., C.1 aRavi, V.  uhttps://library.ncl.res.in/content/phase-evolution-nitio3-prepared-coprecipitation-method-001439nas a2200241   4500008004100000022001400041245005000055210004900105260009900154300001200253490000700265520067900272653002100951653001300972653002400985653001101009653002201020100001901042700001901061700002001080700001301100856008401113       2007                        eng d  a0272-884200aCo-precipitation technique to prepare BaTa2O60 aCoprecipitation technique to prepare BaTa2O6  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcJAN  a297-2990 v333 a<p>A mixture of ammonium oxalate and ammonium hydroxide was used to co-precipitate barium and tantalum ions as barium oxalate and tantalum hydroxide under basic conditions. On calcination at 750 degrees C, this precursor yielded BaTa2O6 (BT) ceramics. This is much lower temperature as compared to that prepared by traditional solid-state method (1000 degrees C) as reported for the formation of BaTa206. Transmission electron microscope (TEM) investigations revealed that the average particle size is 70 nm for the calcined powders. The room temperature dielectric constant at 1 kHz is found to be 100. (c) 2005 Elsevier Ltd and Techna Group S.r.l. All rights reserved.</p>10abarium tantalate10aCeramics10aElectron microscopy10aOxides10aX-ray diffraction1 aNavale, S., C.1 aSamuel, Violet1 aGaikwad, A., B.1 aRavi, V.  uhttps://library.ncl.res.in/content/co-precipitation-technique-prepare-bata2o6-001385nas a2200229   4500008004100000022001400041245003700055210003600092260009900128300001200227490000700239520071800246653001300964653001100977653002100988653000901009653001301018100001901031700002101050700001301071856007101084       2007                        eng d  a0272-884200aVaristors based on Ta-doped TiO20 aVaristors based on Tadoped TiO2  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcMAR  a301-3030 v333 a<p>The nonlinear current (I)-voltage (V) characteristics of titanium dioxide are examined when doped with small quantities (0.05-0.5 at.%) of tantalum pentaoxide. For optimum compositions, the nonlinear coefficients are found to be in the range of 25-30 and the breakdown field strength (EB) is similar to 4000 V/cm. The obtained alpha- and E-B-values are higher than the previously reported values for TiO2 ceramics. The acceptor like surface states at the grain boundary adsorb oxygen during sintering and cooling, leading to formation of grain boundary barrier. The grain boundary barrier height (OB) is calculated using Schottky equation. (c) 2005 Elsevier Ltd and Techna Group S.r.l. All rights reserved.</p>10aCeramics10aOxides10aSchottky barrier10aTiO210avaristor1 aNavale, S., C.1 aMurugan, Vadivel1 aRavi, V.  uhttps://library.ncl.res.in/content/varistors-based-ta-doped-tio2-0