02294nas a2200241   4500008004100000022001400041245010300055210006900158260008700227300001200314490000700326520137000333653002301703653002301726653002201749653003701771653002201808100002001830700001501850700003301865700002501898856012901923       2005                        eng d  a0095-244300aCure characteristics and dielectric properties of magnetic composites containing strontium ferrite0 aCure characteristics and dielectric properties of magnetic compo  a1 OLIVERS YARD, 55 CITY ROAD, LONDON EC1Y 1SP, ENGLANDbSAGE PUBLICATIONS LTDcAPR  a109-1210 v373 a<p>Hexagonal strontium ferrite (SrFe12O19) powders were synthesized by the conventional ceramic techniques. They were then characterized by the X-ray diffraction method and incorporated in the natural rubber matrix according to a specific recipe for various loadings of ferrite to produce rubber ferrite composites (RFCs). The processability of these compounds was determined by evaluating the cure characteristics namely, scorch time, cure time, minimum and maximum torque. The evaluation of the dielectric properties of ceramic strontium ferrite (SrF), natural rubber gum vulcanizate, and RFCs were done with the help of a Hewlett Packard (HP) impedance analyzer. The magnetic properties of these composites were studied using a Vibrating Sample Magnetometer (VSM). The effect of carbon black on the processability, and the magnetic and dielectric properties were also studied by the incorporation of carbon black into these composites. It has been found that the addition of these ferrites and carbon black does not affect the processability of these composites, whereas the physical properties are found to be modified. From the magnetic and dielectric measurements it has been found that flexible magnets having appropriate dielectric strength can be prepared by the incorporation of appropriate amount of SrF and carbon black in the natural rubber matrix.</p>10ahexagonal ferrites10aMagnetic materials10apermanent magnets10arubber ferrite composites (RFCs)10astrontium ferrite1 aSoloman, M., A.1 aKurian, P.1 aAnantharaman, Maliemadom, R.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/cure-characteristics-and-dielectric-properties-magnetic-composites-containing-strontium-001882nas a2200241   4500008004100000022001400041245011400055210006900169260008900238300001200327490000700339520096200346653001901308653001701327653002301344653001901367653003001386100002001416700001501436700003301451700002501484856013101509       2005                        eng d  a0971-457X00aMagnetic and processability studies of nitrile rubber vulcanisates containing barium ferrite and carbon black0 aMagnetic and processability studies of nitrile rubber vulcanisat  aDR K S KRISHNAN MARG, NEW DELHI 110 012, INDIAbNATL INST SCIENCE COMMUNICATIONcSEP  a582-5870 v123 a<p>Fine particles of barium ferrite (BaFe12O19) belonging to the M-type hexagonal ferrites were prepared by the conventional ceramic techniques. They were incorporated into a nitrile rubber matrix according to a specific recipe for various loadings to produce rubber ferrite composites (RFC)The percolation threshold is not reached for a maximum loading of 130 phr (parts per hundred rubber). Here in this paper, the magnetic properties and processability of the nitrile rubber based RFCs containing barium ferrite (BaF) and HAF carbon black is reported. The magnetic properties of the ceramic ferrite and these rubber ferrite composites were evaluated and it was found that the coercivity values of RFCs were less than that of the ceramic BaF, but remained constant with the loading of both the ferrite filler and carbon black. However, other properties like saturation magnetization and magnetic remanence increased with the loading of ferrite filler.</p>10abarium ferrite10acarbon black10aMagnetic materials10anitrile rubber10arubber ferrite composites1 aSoloman, M., A.1 aKurian, P.1 aAnantharaman, Maliemadom, R.1 aJoy, Pattayil, Alias  uhttps://library.ncl.res.in/content/magnetic-and-processability-studies-nitrile-rubber-vulcanisates-containing-barium-ferrite-002223nas a2200229   4500008004100000022001400041245010700055210006900162260008100231300001400312490000700326520137100333100001401704700001401718700001801732700002201750700002001772700002501792700002001817700003301837856012301870       2006                        eng d  a0022-372700aEffect of thermal annealing on Fe40Ni38B18Mo4 thin films: modified Herzer model for magnetic evolution0 aEffect of thermal annealing on Fe40Ni38B18Mo4 thin films modifie  aTEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcMAY  a1993-20000 v393 a<p>Magnetic properties of nano-crystalline soft magnetic alloys have usually been correlated to structural evolution with heat treatment. However, literature reports pertaining to the study of nano-crystalline thin films are less abundant. Thin films of Fe40Ni38B18Mo4 were deposited on glass substrates under a high vacuum of approximate to 10(-6) Torr by employing resistive heating. They were annealed at various temperatures ranging from 373 to 773K based on differential scanning calorimetric studies carried out on the ribbons. The magnetic characteristics were investigated using vibrating sample magnetometry. Morphological characterizations were carried out using atomic force microscopy (AFM), and magnetic force microscopy (MFM) imaging is used to study the domain characteristics. The variation of magnetic properties with thermal annealing is also investigated. From AFM and MFM images it can be inferred that the crystallization temperature of the as-prepared films are lower than their bulk counterparts. Also there is a progressive evolution of coercivity up to 573 K, which is an indication of the lowering of nano-crystallization temperature in thin films. The variation of coercivity with the structural evolution of the thin films with annealing is discussed and a plausible explanation is provided using the modified random anisotropy model.</p>1 aHysen, T.1 aDeepa, S.1 aSaravanan, S.1 aRamanujan, R., V.1 aAvasthi, D., K.1 aJoy, Pattayil, Alias1 aKulkarni, S., D1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/effect-thermal-annealing-fe40ni38b18mo4-thin-films-modified-herzer-model-magnetic-002118nas a2200217   4500008004100000022001400041245009100055210006900146260008000215300001400295490000700309520130500316100001901621700002201640700001901662700002501681700001801706700002201724700003301746856012101779       2006                        eng d  a0957-448400aEvidence for intergranular tunnelling in polyaniline passivated alpha-Fe nanoparticles0 aEvidence for intergranular tunnelling in polyaniline passivated   aDIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcSEP  a4765-47720 v173 a<p>Nanoparticles are of immense importance both from the fundamental and application points of view. They exhibit quantum size effects which are manifested in their improved magnetic and electric properties. Mechanical attrition by high energy ball milling (HEBM) is a top down process for producing fine particles. However, fineness is associated with high surface area and hence is prone to oxidation which has a detrimental effect on the useful properties of these materials. Passivation of nanoparticles is known to inhibit surface oxidation. At the same time, coating polymer film on inorganic materials modifies the surface properties drastically. In this work a modified set-up consisting of an RF plasma polymerization technique is employed to coat a thin layer of a polymer film on Fe nanoparticles produced by HEBM. Ball-milled particles having different particle size ranges are coated with polyaniline. Their electrical properties are investigated by measuring the dc conductivity in the temperature range 10-300 K. The low temperature dc conductivity (I-V) exhibited nonlinearity. This nonlinearity observed is explained on the basis of the critical path model. There is clear-cut evidence for the occurrence of intergranular tunnelling. The results are presented here in this paper.</p>1 aSunny, Vijutha1 aNarayanan, T., N.1 aSajeev, U., S.1 aJoy, Pattayil, Alias1 aKumar, Sakthi1 aYoshida, Yasuhiko1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/evidence-intergranular-tunnelling-polyaniline-passivated-alpha-fe-nanoparticles-002014nas a2200253   4500008004100000022001400041245010500055210006900160260007300229300001200302490000800314520111200322653001501434653002401449653001801473653001901491653001101510100001501521700001701536700001701553700002501570700003301595856013201628       2006                        eng d  a0304-885300aFinite size effects on the structural and magnetic properties of sol-gel synthesized NiFe2O4 powders0 aFinite size effects on the structural and magnetic properties of  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL  a190-1950 v3023 a<p>Nanoparticles of nickel ferrite have been synthesized by the sol-gel method and the effect of grain size oil its structural and magnetic properties have been Studied in detail. X-ray diffraction (XRD) studies revealed that all the samples are single phasic possessing the inverse spinel structure. Grain size of the sol-gel synthesized powders has been determined from the XRD data and the strain graph. A grain size of 9 nm was observed for the as prepared powders of NiFe2O4 obtained through the sol-gel method. It was also observed that strain was induced during the firing process. Magnetization measurements have been carried out on all the samples prepared in the present series. It was found that the specific magnetization of the nanosized NiFe2O4 powders was lower than that of the corresponding coarse-grained counterparts and decreased with a decrease in grain size. The coercivity of the sol-gel synthesized NiFe2O4 nanoparticles attained a maximum value when the grain size was 15 nm and then decreased as the grain size was increased further. (c) 2005 Elsevier B.V. All rights reserved.</p>10agrain size10amagnetic properties10aNanoparticles10aNickel ferrite10astrain1 aGeorge, M.1 aJohn, A., M.1 aNair, S., S.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/finite-size-effects-structural-and-magnetic-properties-sol-gel-synthesized-nife2o4-powders-001519nas 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-001618nas a2200193   4500008004100000022001400041245017500055210006900230260008000299300001400379490000700393520078000400100001901180700002101199700001901220700002501239700003301264856012701297       2007                        eng d  a0022-372700aFinite size effects on the electrical properties of sol-gel synthesized CoFe2O4 powders: deviation from Maxwell-Wagner theory and evidence of surface polarization effects0 aFinite size effects on the electrical properties of solgel synth  aDIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLANDbIOP PUBLISHING LTDcMAR  a1593-16020 v403 a<p>Fine particles of cobalt ferrite were synthesized by the sol-gel method. Subsequent heat treatment at different temperatures yielded cobalt ferrites having different grain sizes. X-ray diffraction studies were carried out to elucidate the structure of all the samples. Dielectric permittivity and ac conductivity of all the samples were evaluated as a function of frequency, temperature and grain size. The variation of permittivity and ac conductivity with frequency reveals that the dispersion is due to Maxwell-Wagner type interfacial polarization in general, with a noted variation from the expected behaviour for the cold synthesized samples. High permittivity and conductivity for small grains were explained on the basis of the correlated barrier-hopping model.</p>1 aGeorge, Mathew1 aNair, Swapna, S.1 aMalini, K., A.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/finite-size-effects-electrical-properties-sol-gel-synthesized-cofe2o4-powders-deviation02072nas 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-001712nas a2200253   4500008004100000022001400041245009000055210006900145260008600214300001200300490000700312520081400319653001201133653002301145653002101168653002001189653001101209653001901220100001801239700001901257700002501276700003301301856012401334       2008                        eng d  a0360-255900aPhysicomechanical and magnetic properties of neoprene based rubber ferrite composites0 aPhysicomechanical and magnetic properties of neoprene based rubb  a325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USAbTAYLOR & FRANCIS INCcJAN  a137-1460 v473 a<p>Fine (approximately 18nm) particles of nickel ferrite were synthesized by the sol-gel technique, and their structural properties were evaluated by X-ray diffraction. Neoprene-based rubber ferrite composites were prepared by incorporating these nickel ferrite powders in the rubber matrix according to a specific recipe. The cure characteristics were analyzed, and the samples were molded into particular shapes whose properties were determined according to ASTM standards. Magnetization studies were carried out using a Vibrating Sample Magnetometer. This study indicates that neoprene rubber-based flexible magnets with desired magnetic properties and appropriate mechanical properties can be prepared by incorporating an adequate amount of nanoscale nickel ferrite particles within the rubber matrix.</p>10aFerrite10aferrite composites10aflexible magnets10aneoprene rubber10arubber10aSol-gel method1 aPrema, K., H.1 aKurian, Philip1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/physicomechanical-and-magnetic-properties-neoprene-based-rubber-ferrite-composites-001661nas a2200193   4500008004100000022001400041245011900055210006900174260005700243300001200300490000700312520090000319100002701219700001601246700002501262700001901287700003301306856012801339       2009                        eng d  a0947-839600aEffect of nickel nanofillers on the dielectric and magnetic properties of composites based on rubber in the X-band0 aEffect of nickel nanofillers on the dielectric and magnetic prop  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcOCT  a157-1650 v973 a<p>Nickel-rubber nanocomposites were synthesized by incorporating ferromagnetic nickel nanoparticles in a natural rubber as well as neoprene rubber matrix. Complex dielectric permittivity and magnetic permeability of these composites were evaluated in the X-band microwave frequencies at room temperature using cavity perturbation technique. The dielectric loss in natural rubber is smaller compared to neoprene rubber. A steady increase in the dielectric permittivity is observed with increase in the content of nickel in both the composites. The magnetic permeability exhibits a steady decrease with increase in frequency and magnetic loss shows a relaxation at 8 GHz. The suitability of these composites as microwave absorbers is modeled based on the reflection loss which is dependant on the real and imaginary components of the complex dielectric permittivity and magnetic permeability.</p>1 aJamal, Muhammad, Abdul1 aMohanan, P.1 aJoy, Pattayil, Alias1 aKurian, Philip1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/effect-nickel-nanofillers-dielectric-and-magnetic-properties-composites-based-rubber-x-002159nas a2200229   4500008004100000022001400041245013600055210006900191260007300260300001400333490000800347520126000355653002701615100001901642700002101661700001901682700002501701700001801726700002201744700003301766856013001799       2009                        eng d  a0304-885300aImpact of zinc substitution on the structural and magnetic properties of chemically derived nanosized manganese zinc mixed ferrites0 aImpact of zinc substitution on the structural and magnetic prope  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR  a1092-10990 v3213 a<p>Mn(1-x)Zn(x)Fe(2)O(4) nanoparticles (x = 0-1) were synthesized by wet chemical co-precipitation techniques. X-ray diffraction, transmission electron microscopy and high-resolution transmission electron microscopy were effectively utilized to investigate the different structural parameters. The elemental analysis was conducted using energy-dispersive spectrum and inductively coupled plasma analysis. The magnetic properties such as magnetization and coercivity were measured using vibrating sample magnetometer. The observed magnetization values of the nanoparticles were found to be lower compared to the bulk counterpart. The magnetization showed a gradual decrease with zinc substitution except for a small increase from x = 0.2 to 0.3. The Curie temperature was found to be enhanced in the case of ferrites in the nanoregime. The variation in lattice constant, reduced magnetization values, variation of magnetization with zinc substitution, the presence of a net magnetic moment for the zinc ferrite and the enhancement in Curie temperature in Mn(1-x)Zn(x)Fe(2)O(4) all provide evidence to the existence of a metastable cation distribution together with possible surface effects at the nanoregime. (C) 2008 Elsevier B.V. All rights reserved.</p>10aManganese zinc ferrite1 aGopalan, Veena1 aAl-Omari, I., A.1 aMalini, K., A.1 aJoy, Pattayil, Alias1 aKumar, Sakthi1 aYoshida, Yasuhiko1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/impact-zinc-substitution-structural-and-magnetic-properties-chemically-derived-nanosized-001249nas a2200205   4500008004100000022001400041245004800055210004800103260009200151300001800243490000800261520056500269653002400834653001400858653001700872100001400889700002500903700003300928856008200961       2009                        eng d  a0015-019300aMultiferroic behavior of gd based manganite0 aMultiferroic behavior of gd based manganite  a4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLANDbTAYLOR & FRANCIS LTDcOCT  aPII 9173249710 v3923 a<p>Here we report the multiferroic nature of charge ordered manganite Gd0.5Sr0.5MnO3 for the first time. The temperature variation of dielectric constant shows broad relaxor type ferroelectric transition at around 210K and magnetization measurements shows weak ferromagnetism at 50K. The dielectric peak is very close to charge ordering temperature which is an evidence of the link between electronic state and increase of dielectric response. Butterfly variation of capacitance with voltage confirms ferroelectric nature of the sample at room temperature.</p>10adielectric constant10amanganite10aMultiferroic1 aSagar, S.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/multiferroic-behavior-gd-based-manganite-002007nas a2200289   4500008004100000022001400041245010200055210006900157260006900226300001200295490000800307520093700315653002501252653002601277653003501303653001901338653005001357653002201407653002201429100001901451700002501470700002101495700001801516700002201534700003301556856012801589       2009                        eng d  a0925-838800aOn the structural, magnetic and electrical properties of sol-gel derived nanosized cobalt ferrite0 astructural magnetic and electrical properties of solgel derived   aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcOCT  a711-7170 v4853 a<p>Nanoparticles of cobalt ferrite were synthesized by sol gel method. These particles were structurally characterized by using X-Ray Diffraction and Transmission Electron Microscopy, High Resolution Transmission Electron Microscopy, Energy Dispersive Spectrum and Inductively Coupled Plasma Analysis and the results confirmed the formation of spherically shaped nanoparticles of cobalt ferrite having a size lying in the range of 13-14 nm. The as prepared sample was sintered at 800 degrees C and the structural, magnetic and dielectric properties were measured. The dielectric properties were studied and analyzed as a function of temperature and frequency. The ac and dc conductivity studies were carried out to delve into the conduction mechanism. The existing models based on quantum mechanical tunneling were effectively employed to explain the frequency dependent conductivity. (C) 2009 Elsevier B.V. All rights reserved.</p>10aElectronic Transport10aMagnetic measurements10aMagnetically ordered materials10aNanostructures10aScanning and transmission electron microscopy10aSol-gel synthesis10aX-ray diffraction1 aGopalan, Veena1 aJoy, Pattayil, Alias1 aAl-Omari, I., A.1 aKumar, Sakthi1 aYoshida, Yasuhiko1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/structural-magnetic-and-electrical-properties-sol-gel-derived-nanosized-cobalt-ferrite-001842nas a2200217   4500008004100000022001400041245009200055210006900147260007300216300001000289490000800299520101600307653002601323653002901349653001901378100002701397700002501424700001901449700003301468856012301501       2009                        eng d  a0921-510700aSynthesis of nickel-rubber nanocomposites and evaluation of their dielectric properties0 aSynthesis of nickelrubber nanocomposites and evaluation of their  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJAN  a24-310 v1563 a<p>Nanocomposites based on natural rubber and nano-sized nickel were synthesized by incorporating nickel nanoparticles in a natural rubber matrix for various loadings of the filler. Structural, morphological, magnetic and mechanical properties of the composites were evaluated along with a detailed study of dielectric properties. It was found that nickel particles were uniformly distributed in the matrix without agglomeration resulting ill a magnetic nanocomposite. The elastic properties showed an improvement with increase in filler content but breaking stress and breaking strain were found to decrease. Dielectric permittivity was found to decrease with increase in frequency, and found to increase with increase in nickel loading. The decrease in permittivity with temperature is attributed to the high volume expansivity of rubber at elevated temperatures. Dielectric loss of blank rubber as well as the composites was found to increase with temperature. (C) 2008 Elsevier B.V. All rights reserved.</p>10aDielectric relaxation10aInterfacial polarization10aNanocomposites1 aJamal, Muhammad, Abdul1 aJoy, Pattayil, Alias1 aKurian, Philip1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/synthesis-nickel-rubber-nanocomposites-and-evaluation-their-dielectric-properties-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-001783nas a2200265   4500008004100000022001400041245007000055210006900125260006900194300001200263490000800275520088300283653002401166653002501190653002501215653002301240653001901263653001901282100001901301700001901320700001601339700002501355700003301380856010401413       2010                        eng d  a0925-838800aFlexible microwave absorber based on nickel ferrite nanocomposite0 aFlexible microwave absorber based on nickel ferrite nanocomposit  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcJAN  a297-3030 v4893 a<p>Flexible magnetic composite materials were prepared by incorporating precharacterized nickel ferrite nanoparticles in a natural rubber matrix. The complex dielectric permittivity and magnetic permeability of the composites were measured at different microwave frequencies using the cavity perturbation technique. A steady increase in dielectric permittivity was observed with increase in filler concentration. Maxwell-Garnett mixture equations were employed to model the effective permittivity and permeability of the composite. Reflection loss was estimated by employing the model of single layer absorber backed with a perfect conductor. Reflection loss minima of -5.9 dB at 3.2 GHz for 12 mm thick rubber ferrite composite sheet is obtained in the S-band while a loss up to -16 dB could be achieved at 9.5 GHz in the X-band. (C) 2009 Elsevier B.V. All rights reserved.</p>10aCavity perturbation10aComplex permeability10aComplex permittivity10aMicrowave absorber10aNanocomposites10aNickel ferrite1 aSunny, Vijutha1 aKurian, Philip1 aMohanan, P.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/flexible-microwave-absorber-based-nickel-ferrite-nanocomposite-001464nas a2200205   4500008004100000022001400041245007800055210006900133260005700202300001200259490000700271520073000278100001901008700002101027700001801048700002201066700002501088700003301113856011201146       2010                        eng d  a0947-839600aInverse magnetocaloric effect in sol-gel derived nanosized cobalt ferrite0 aInverse magnetocaloric effect in solgel derived nanosized cobalt  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcMAY  a497-5030 v993 a<p>The magnetocaloric properties of cobalt ferrite nanoparticles were investigated to evaluate the potential of these materials as magnetic refrigerants. Nanosized cobalt ferrites were synthesized by the method of sol-gel combustion. The nanoparticles were found to be spherical with an average crystallite size of 14 nm. The magnetic entropy change (Delta S (m)) calculated indirectly from magnetization isotherms in the temperature region 170-320 K was found to be negative, signifying an inverse magnetocaloric effect in the nanoparticles. The magnitudes of the Delta S (m) values were found to be larger when compared to the reported values in the literature for the corresponding ferrite materials in the nanoregime.</p>1 aGopalan, Veena1 aAl-Omari, I., A.1 aKumar, Sakthi1 aYoshida, Yasuhiko1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/inverse-magnetocaloric-effect-sol-gel-derived-nanosized-cobalt-ferrite-001863nas a2200229   4500008004100000022001400041245008100055210006900136260006900205300001200274490000800286520103800294653002401332653002601356653001501382653002401397100002701421700002501448700001901473700003301492856010801525       2010                        eng d  a0254-058400aOn the magnetic and dielectric properties of nickel-neoprene nanoconaposites0 amagnetic and dielectric properties of nickelneoprene nanoconapos  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcMAY  a154-1600 v1213 a<p>Nickel nanocomposites were prepared by incorporating nickel nanoparticles in a neoprene matrix according to a specific recipe for various loadings of nickel particles. The dielectric properties of these composites were evaluated for different frequencies ranging from 100 kHz to 8 MHz at different temperatures from 30 degrees C to 120 degrees C. The dielectric permittivity increases with increase of nickel concentration. Increase in temperature enhances the permittivity initially, till 40 degrees C and thereafter the permittivity decreases. The dielectric loss exhibits relaxation peaks and the peaks shift to lower frequencies with increase in volume fraction of the nickel nanoparticles in the matrix. The evaluation of magnetic and dielectric properties of these composites suggests that the dielectric permittivity can be tailored by an appropriate loading of the filler using semi-empirical equations and the magnetic properties vary according to simple mixture equations. (C) 2010 Elsevier B.V. All rights reserved.</p>10aComposite materials10adielectric properties10aElastomers10amagnetic properties1 aJamal, Muhammad, Abdul1 aJoy, Pattayil, Alias1 aKurian, Philip1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/magnetic-and-dielectric-properties-nickel-neoprene-nanoconaposites-001870nas a2200229   4500008004100000022001400041245009100055210006900146260005700215300001200272490000700284520104000291653002501331653002001356653002401376653001901400100002701419700002501446700001901471700003301490856011701523       2010                        eng d  a0170-083900aOn the magnetic, mechanical and rheological properties of rubber-nickel nanocomposites0 amagnetic mechanical and rheological properties of rubbernickel n  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcMAY  a907-9230 v643 a<p>Rubber-nickel nanocomposites were synthesized by incorporating freshly prepared nanometric nickel particles in two different matrices namely natural rubber and neoprene rubber according to specific recipes for various loadings of nano nickel and the cure characteristics of these composites were evaluated. The maximum torque values register an increase with the increase in loading of nickel in both composites and this is attributed to the non-interacting nature of nickel nanoparticles with rubber matrices. The cure time of natural rubber composites decreases with increase in the content of nickel, and in neoprene rubber cure, time increases with increase in filler content. In natural rubber, the curing reaction seems to be activated by the presence of nickel particles. The magnetization studies of the composites reveal that the magnetic properties of nickel are retained in the composite samples. The elastic modulus of natural rubber and neoprene rubber are largely improved by the incorporation of nickel particles.</p>10aCure characteristics10aElastic modulus10amagnetic properties10aNanocomposites1 aJamal, Muhammad, Abdul1 aJoy, Pattayil, Alias1 aKurian, Philip1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/magnetic-mechanical-and-rheological-properties-rubber-nickel-nanocomposites-002114nas a2200277   4500008004100000022001400041245013400055210006900189260005700258300001400315490000600329520109600335653002101431653002601452653002401478653001501502653002301517100002701540700002201567700001901589700002001608700002201628700002501650700003301675856012801708       2010                        eng d  a1931-757300aSynthesis of bio-compatible SPION-based aqueous ferrofluids and evaluation of radiofrequency power loss for magnetic hyperthermia0 aSynthesis of biocompatible SPIONbased aqueous ferrofluids and ev  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcOCT  a1706-17110 v53 a<p>Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc). This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm) exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.</p>10aMagnetic heating10aMagnetic hyperthermia10aMagnetic relaxation10aPower loss10aSuperparamagnetism1 aMary, Antony, P. Reena1 aNarayanan, T., N.1 aSunny, Vijutha1 aSakthikumar, D.1 aYoshida, Yasuhiko1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/synthesis-bio-compatible-spion-based-aqueous-ferrofluids-and-evaluation-radiofrequency-002649nas a2200301   4500008004100000022001400041245008800055210006900143260005700212300001200269490000600281520155900287653002501846653003301871653004201904653003801946653004001984100001902024700001902043700002202062700002202084700002502106700002102131700001802152700002202170700003302192856012202225       2010                        eng d  a1556-276X00aTemplate-assisted synthesis and characterization of passivated nickel nanoparticles0 aTemplateassisted synthesis and characterization of passivated ni  a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcMAY  a889-8970 v53 a<p>Potential applications of nickel nanoparticles demand the synthesis of self-protected nickel nanoparticles by different synthesis techniques. A novel and simple technique for the synthesis of self-protected nickel nanoparticles is realized by the inter-matrix synthesis of nickel nanoparticles by cation exchange reduction in two types of resins. Two different polymer templates namely strongly acidic cation exchange resins and weakly acidic cation exchange resins provided with cation exchange sites which can anchor metal cations by the ion exchange process are used. The nickel ions which are held at the cation exchange sites by ion fixation can be subsequently reduced to metal nanoparticles by using sodium borohydride as the reducing agent. The composites are cycled repeating the loading reduction cycle involved in the synthesis procedure. X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron microscopy, Energy Dispersive Spectrum, and Inductively Coupled Plasma Analysis are effectively utilized to investigate the different structural characteristics of the nanocomposites. The hysteresis loop parameters namely saturation magnetization and coercivity are measured using Vibrating Sample Magnetometer. The thermomagnetization study is also conducted to evaluate the Curie temperature values of the composites. The effect of cycling on the structural and magnetic characteristics of the two composites are dealt in detail. A comparison between the different characteristics of the two nanocomposites is also provided.</p>10aNickel nanoparticles10aPolymer-metal nanocomposites10aStrongly acidic cation exchange resin10aStuctural and magnetic properties10aWeakly acidic cation exchange resin1 aGopalan, Veena1 aMalini, K., A.1 aSanthoshkumar, G.1 aNarayanan, T., N.1 aJoy, Pattayil, Alias1 aAl-Omari, I., A.1 aKumar, Sakthi1 aYoshida, Yasuhiko1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/template-assisted-synthesis-and-characterization-passivated-nickel-nanoparticles-002509nas a2200325   4500008004100000022001400041245009900055210006900154260009200223300001200315490000600327520135500333653001001688653001601698653002301714653001001737653002201747100002301769700003101792700003101823700002701854700002501881700002201906700001901928700002301947700002301970700002501993700003302018856013202051       2012                        eng d  a2158-584900aFluorescent superparamagnetic iron oxide core-shell nanoprobes for multimodal cellular imaging0 aFluorescent superparamagnetic iron oxide coreshell nanoprobes fo  a26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USAbAMER SCIENTIFIC PUBLISHERScDEC  a265-2740 v23 a<p>Multimodal imaging agents that combine magnetic and fluorescent imaging capabilities are desirable for the high spatial and temporal resolution. In the present work, we report the synthesis of multifunctional fluorescent ferrofluids using iron oxide as the magnetic core and rhodamine B as fluorochrome shell. The core-shell structure was designed in such a way that fluorescence quenching due to the inner magnetic core was minimized by an intermediate layer of silica. The intermediate passive layer of silica was realized by a novel method which involves the esterification reaction between the epoxy group of prehydrolysed 3-Glyidoxypropyltrimethoxysilane and the surfactant over iron oxide. The as-synthesized ferrofluids have a high saturation magnetization in the range of 62-65 emu/g and were found to emit light of wavelength 640 nm (lambda(excitation) = 446 nm). Time resolved life time decay analysis showed a bi-exponential decay pattern with an increase in the decay life time in the presence of intermediate silica layer. Cytotoxicity studies confirmed the cell viability of these materials. The in vitro MRI imaging illustrated a high contrast when these multimodal nano probes were employed and the R2 relaxivity of these sample was found to be 334 mM(-1)s(-1) which reveals its high potential as a T2 contrast enhancing agent.</p>10aGPTMS10aMRI Imaging10aMultimodal Imaging10aSPION10aT2 Contrast Agent1 aSmitha, Sasidharan1 aHaseena, Vadakkenchery, S.1 aNarayanan, Tharangattu, N.1 aMary, Antony, P. Reena1 aAjayan, Pulickel, M.1 aPuthumana, Jayesh1 aAziz, Anas, A.1 aAburto, Rebeca, R.1 aMani, Sendurai, A.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/fluorescent-superparamagnetic-iron-oxide-core-shell-nanoprobes-multimodal-cellular-imaging-001742nas a2200241   4500008004100000022001400041245013100055210006900186260012500255300001100380490000800391520077200399100002101171700001501192700001901207700002101226700002201247700001801269700002501287700002501312700003301337856013001370       2013                        eng d  a0003-695100aContact potential induced enhancement of magnetization in polyaniline coated nanomagnetic iron oxides by plasma polymerization0 aContact potential induced enhancement of magnetization in polyan  aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScOCT  a1624140 v1033 a<p>The present work derives motivation from the so called surface/interfacial magnetism in core shell structures and commercial samples of Fe3O4 and gamma Fe2O3 with sizes ranging from 20 to 30 nm were coated with polyaniline using plasma polymerization and studied. The High Resolution Transmission Electron Microscopy images indicate a core shell structure after polyaniline coating and exhibited an increase in saturation magnetization by 2 emu/g. For confirmation, plasma polymerization was performed on maghemite nanoparticles which also exhibited an increase in saturation magnetization. This enhanced magnetization is rather surprising and the reason is found to be an interfacial phenomenon resulting from a contact potential. (C) 2013 AIP Publishing LLC.</p>1 aSethulakshmi, N.1 aSooraj, V.1 aSajeev, U., S.1 aNair, Swapna, S.1 aNarayanan, T., N.1 aJoy, Lija, K.1 aJoy, Pattayil, Alias1 aAjayan, Pulickel, M.1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/contact-potential-induced-enhancement-magnetization-polyaniline-coated-nanomagnetic-iron-001908nas a2200217   4500008004100000022001400041245012100055210006900176260012500245300001100370490000800381520101800389100001901407700002001426700001901446700001601465700001901481700002501500700003301525856013201558       2014                        eng d  a0021-897900aFlexible microwave absorbers based on barium hexaferrite, carbon black, and nitrile rubber for 2-12 GHz applications0 aFlexible microwave absorbers based on barium hexaferrite carbon   aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScJUL  a0249020 v1163 a<p>Flexile single layer electromagnetic wave absorbers were designed by incorporating appropriate amounts of carbon black in a nitrile butadiene rubber matrix along with an optimized amount of magnetic counterpart, namely, barium hexaferrite for applications in S, C, and X-bands. Effective dielectric permittivity and magnetic permeability were measured using cavity perturbation method in the frequency range of 2-12 GHz. The microwave absorbing characteristics of the composites were studied in the S, C, and X-bands employing a model in which an electromagnetic wave is incident normally on a metal terminated single layer. Reflection loss exceeding -20 dB is obtained for all the samples in a wide frequency range of 2-12 GHz when an appropriate absorber thickness between 5 and 9 mm is chosen. The impact of carbon black is clearly observed in the optimized composites on the mechanical strength, thickness, band width of absorption, dielectric properties, and absorptivity. (C) 2014 AIP Publishing LLC.</p>1 aVinayasree, S.1 aSoloman, M., A.1 aSunny, Vijutha1 aMohanan, P.1 aKurian, Philip1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R.  uhttps://library.ncl.res.in/content/flexible-microwave-absorbers-based-barium-hexaferrite-carbon-black-and-nitrile-rubber-2-12-0