01322nas a2200217   4500008004100000022001400041245009700055210006900152260010600221300001200327490000800339520049000347653002700837653002400864653001700888100001600905700001900921700001700940700002500957856012200982       2007                        eng d  a0038-109800aDirect comparison of the aging and memory effects of magnetic nanoclusters and nanoparticles0 aDirect comparison of the aging and memory effects of magnetic na  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcFEB  a307-3100 v1413 a<p>The magnetic characteristics of a dense magnetic nanoparticle system and a spin glass system consisting of magnetic nanoclusters are compared. Zero field cooled and field cooled magnetization measurements, including aging and memory experiments, of the nanoparticle and the magnetic cluster systems show similar characteristics, suggesting a common origin for the spin glass-type behavior of the magnetic nanoparticle and nanocluster systems. (C) 2006 Published by Elsevier Ltd.</p>10aMagnetic nanoparticles10amagnetic properties10aspin glasses1 aSankar, Raj1 aVijayanand, S.1 aVerma, Seema1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/direct-comparison-aging-and-memory-effects-magnetic-nanoclusters-and-nanoparticles01727nas a2200229   4500008004100000022001400041245011400055210006900169260007400238300001100312490000800323520088300331653001201214653002401226653002701250653001801277100001501295700001901310700001801329700002501347856012501372       2008                        eng d  a0304-384300aMagnetic and Mossbauer spectroscopic studies of NiZn ferrite nanoparticles synthesized by a combustion method0 aMagnetic and Mossbauer spectroscopic studies of NiZn ferrite nan  aVAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDSbSPRINGERcAPR  a99-1070 v1833 a<p>The properties of nanocrystalline Ni(0.5)Zn(0.5)Fe(2)O(4) synthesized by an auto-combustion method have been investigated by magnetic measurements and Mossbauer spectroscopy. The as-synthesized single phase nanosized ferrite powder is annealed at different temperatures in the range 673-1,273 K to obtain nanoparticles of different sizes. The powders are characterized by powder X-ray diffraction, vibrating sample magnetometer, transmission electron microscopy and Mossbauer spectroscopy. The as-synthesized powder with average particle size of similar to 9 nm is superparamagnetic. Magnetic transition temperature increases up to 665 K for the nanosized powder as compared to the transition temperature of 548 K for the bulk ferrite. This has been confirmed as due to the abnormal cation distribution, as evidenced from room temperature Mossbauer spectroscopic studies.</p>10aFerrite10amagnetic properties10aMossbauer spectroscopy10aNanoparticles1 aSreeja, V.1 aVijayanand, S.1 aDeka, Sasanka1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/magnetic-and-mossbauer-spectroscopic-studies-nizn-ferrite-nanoparticles-synthesized-002189nas a2200229   4500008004100000022001400041245010800055210006900163260010600232300001400338490000700352520131000359653002501669653001901694653002201713100002001735700001901755700001901774700002001793700001801813856012801831       2008                        eng d  a0025-540800aPhotocatalytic decomposition of methylene nanocrystalline titania prepared by different blue on methods0 aPhotocatalytic decomposition of methylene nanocrystalline titani  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcMAY  a1145-11520 v433 a<p>Nanocrystalline particles of pure anatase titania were prepared by two different methods. One is the sol-gel method at ambient temperature using ultrasonication (TiO2-SG-US) and conventional stirring method (TiO2-SG-S) and the other by surfactant assisted hydrothermal synthesis (TiO2-HT). More uniform distribution/dispersion of the nanoparticles (SEM), marginally higher surface area, better thermal stability and phase purity are some of the advantages of preparation of nanocrystalline titania by sol gel ultrasonication method and hydrothermal synthesis method. The behavior of anatase titania in photocatalytic decomposition of methylene blue in aqueous medium was studied as a function of the method of preparation and the crystallite size. The nanoparticles prepared by ultrasonication method were more effective than both, the sample prepared by conventional stirring method and commercial Degussa P-25. The higher photocatalytic activity of TiO2-SG-US is attributed to the more uniform size of the particles as compared to TiO2-SG-S samples. Both TEM and XRD data on TiO2-HT samples reveal a uniform and nanocrystalline TiO2 particles, which showed photocatalytic activity in both UV and visible region although brookite phase was also present. (C) 2007 Elsevier Ltd. All rights reserved.</p>10aCatalytic properties10aNanostructures10aSol-gel chemistry1 aRamaswamy, Veda1 aJagtap, Neelam1 aVijayanand, S.1 aBhange, Deu, S.1 aAwati, Preeti  uhttps://library.ncl.res.in/content/photocatalytic-decomposition-methylene-nanocrystalline-titania-prepared-different-blue-001484nas a2200229   4500008004100000022001400041245006800055210006100123260007300184300001200257490000700269520074000276653001901016653002201035653001501057653001501072653001501087100001601102700001901118700002501137856009201162       2009                        eng d  a1293-255800aFerromagnetic to spin glass cross over in (La,Tb)(2/3)Ca1/3MnO30 aFerromagnetic to spin glass cross over in LaTb23Ca13MnO3  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR  a714-7180 v113 a<p>In the series La2/3-xTbxCa1/3MnO3, it is known that the compositions are ferromagnetic for smaller values of x and show spin glass characteristics at larger values of x. Our studies on the magnetic properties of various compositions in the La2/3-xTbxCa1/3MnO3 series show that the cross over from ferromagnetic to spin glass region takes place above x approximate to 1/8. Also, a low temperature anomaly at 30 K, observed in the ac susceptibility curves, disappears for compositions above this critical value of x. A mixed phase region coexists in the narrow compositional range 0.1 &lt;= x &lt;= 0.125, indicating that the ferromagnetic to spin glass cross over is not abrupt. (C) 2008 Elsevier Masson SAS. All rights reserved.</p>10aFerromagnetism10aMagnetic clusters10aManganites10aperovskite10aSpin glass1 aSankar, Raj1 aVijayanand, S.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/ferromagnetic-spin-glass-cross-over-latb23ca13mno3-001628nas a2200289   4500008004100000022001400041245008800055210006900143260007900212300001100291490000700302520063900309653002200948653001900970653001700989653002101006653002501027653001801052653002901070653001801099653001401117100001901131700002501150700001901175700002501194856011901219       2009                        eng d  a1098-012100aMagnetic characteristics of nanocrystalline multiferroic BiFeO3 at low temperatures0 aMagnetic characteristics of nanocrystalline multiferroic BiFeO3   aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMER PHYSICAL SOCcAUG  a0644230 v803 a<p>The magnetic characteristics of nanocrystalline BiFeO3 with average crystallite sizes of similar to 50 and similar to 100 nm are evaluated by studying the temperature and field dependence of magnetization at low temperatures. Different properties such as magnetization, coercivity, and remanence show evidence for changes in the magnetic properties associated with the phase transitions at low temperatures, reported from Raman studies. Detailed field-cooled and zero-field-cooled magnetization measurements show that the likely origin of the changes in the magnetic characteristics is from the changes in the domain structure.</p>10abismuth compounds10acoercive force10acrystallites10amagnetic domains10amagnetic transitions10aMultiferroics10aNanostructured materials10aRaman spectra10aremanence1 aVijayanand, S.1 aMahajan, Mangesh, B.1 aPotdar, H., S.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/magnetic-characteristics-nanocrystalline-multiferroic-bifeo3-low-temperatures-001830nas a2200313   4500008004100000022001400041245009600055210006900151260012500220300001100345490000700356520068900363653002201052653002501074653001701099653002801116653002901144653002401173653002101197653001801218653001801236653002901254653002101283653002201304100001901326700001901345700002501364856012701389       2009                        eng d  a0003-695100aOrigin of high room temperature ferromagnetic moment of nanocrystalline multiferroic BiFeO30 aOrigin of high room temperature ferromagnetic moment of nanocrys  aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScMAY  a1825070 v943 a<p>Single phase nanocrystalline BiFeO3 of average crystallite size similar to 25 nm with very high magnetization at room temperature is synthesized by an autocombustion method. Magnetic measurements above room temperature show deviation between field cooled and zero field cooled magnetization below 645 K, the Neel temperature (T-N) of the bulk material, indicating intrinsic nature of ferromagnetism. However, observation of a broad magnetic transition above T-N of BiFeO3 and extended up to 800 K suggests the presence of Fe3O4 as a possible magnetic impurity phase. Evidence for the presence of Fe3O4 is obtained from detailed analysis of the powder x-ray diffraction pattern.</p>10abismuth compounds10aCombustion synthesis10acrystallites10aferromagnetic materials10ahigh-temperature effects10amagnetic impurities10aMagnetic moments10aMagnetisation10aMultiferroics10aNanostructured materials10aNeel temperature10aX-ray diffraction1 aVijayanand, S.1 aPotdar, H., S.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/origin-high-room-temperature-ferromagnetic-moment-nanocrystalline-multiferroic-bifeo3-002296nas a2200289   4500008004100000022001400041245011600055210006900171260006900240300001200309490000800321520129400329653001301623653002301636653001101659653001401670100001901684700001901703700002801722700001801750700002501768700001901793700002101812700002301833700001901856856013101875       2010                        eng d  a0254-058400aSimple chemical co-precipitation/calcination route for the synthesis of simulated synroc-B and synroc-C powders0 aSimple chemical coprecipitationcalcination route for the synthes  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcOCT  a695-6990 v1233 a<p>A simple chemical co-precipitation/calcination route was developed for the synthesis of simulated synroc-B and synroc-C powders using mostly nitrate salts as starting chemicals and 20% ammonia solution as precipitant. In this route, a mixed solution containing Al-nitrate, Ca-nitrate, Ba-nitrate, zirconyl nitrate and titanyl nitrate in the molar proportion required for synroc-B is added to dilute ammonia solution to precipitate these cations in the form of their hydroxides at room temperature by maintaining pH approximate to 10.5 during precipitation. Formation of a major fluorite phase with minor amounts of anatase, rutile and hollandite phases is observed in the powder obtained after calcination in air at 750 degrees C. Multiphase crystalline synroc-B matrix containing hollandite, perovskite, zirconolite, and rutile phases is obtained after sintering the heat treated powder in the form of pellets at 1230 degrees C for 4h in air. Similarly, pure synroc-C phases with 14 and 20% simulated waste loadings were synthesized following the same synthesis protocol. These pre-treated powders with a high surface area of similar to 25 m(2) g(-1) gave sintered ceramics having density of similar to 90% for 14 and 20% waste loadings. (C) 2010 Elsevier B.V. All rights reserved.</p>10aCeramics10aChemical synthesis10aOxides10aSintering1 aPotdar, H., S.1 aVijayanand, S.1 aMohaideen, Kamal, Khaja1 aPatil, K., R.1 aJoy, Pattayil, Alias1 aMadhavan, Raja1 aKutty, K., V. G.1 aAmbashta, Ritu, D.1 aWattal, P., K.  uhttps://library.ncl.res.in/content/simple-chemical-co-precipitationcalcination-route-synthesis-simulated-synroc-b-and-synroc-001911nas a2200253   4500008004100000022001400041245011100055210006900166260007400235300001300309490000700322520098900329653001701318653002401335653001901359653002601378653001901404100001901423700002101442700001901463700001901482700002501501856013101526       2013                        eng d  a0021-891X00aPorous Co3O4 nanorods as superior electrode material for supercapacitors and rechargeable Li-ion batteries0 aPorous Co3O4 nanorods as superior electrode material for superca  aVAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDSbSPRINGERcOCT  a995-10030 v433 a<p>Porous aggregated nanorods of Co3O4 with a surface area of similar to 100 m(2) g(-1) synthesized without using any templates or surfactants give very high specific capacitance of similar to 780 F g(-1) when used as electrode in a faradaic supercapacitor, with a cycle life of more than 1,000 cycles. Further, in Li-ion batteries when used as an anode, the Co3O4 nanorods achieved a capacity of 1155 mA h g(-1) in the first cycle and upon further cycling it is stabilized at 820 mA h g(-1) for more than 25 cycles. Detailed characterization indicated the stability of the material and the improved performance is attributed to the shorter Li-insertion/desertion pathways offered by the highly porous nanostructures. The environmentally benign and easily scalable method of synthesis of the porous Co3O4 nanorods coupled with the superior electrode characteristics in supercapacitors and Li-ion batteries provide efficient energy storage capabilities with promising applications.</p>10aCobalt oxide10aElectrode materials10aLi-ion battery10aPorous nanostructures10asupercapacitor1 aVijayanand, S.1 aKannan, Ramaiyan1 aPotdar, H., S.1 aPillai, V., K.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/porous-co3o4-nanorods-superior-electrode-material-supercapacitors-and-rechargeable-li-ion-0