00679nas a2200193 4500008004100000022001400041245006100055210006100116260007100177300001400248490000800262100002100270700001300291700001600304700002500320700003000345700001500375856009500390 2005 eng d a0002-786300aBacterial aerobic synthesis of nanocrystalline magnetite0 aBacterial aerobic synthesis of nanocrystalline magnetite a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL a9326-93270 v1271 aBharde, Atul, A.1 aWani, A.1 aShouche, Y.1 aJoy, Pattayil, Alias1 aPrasad, Bhagavatula L. V.1 aSastry, M. uhttps://library.ncl.res.in/content/bacterial-aerobic-synthesis-nanocrystalline-magnetite-002718nas a2200229 4500008004100000022001400041245012700055210006900182260007100251300001600322490000700338520184800345100002002193700001902213700002202232700001502254700002002269700002502289700003002314700001502344856012902359 2005 eng d a0743-746300aCobalt and magnesium ferrite nanoparticles: preparation using liquid foams as templates and their magnetic characteristics0 aCobalt and magnesium ferrite nanoparticles preparation using liq a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV a10638-106430 v213 a

An easy and convenient method for the synthesis of cobalt and magnesium ferrite nanoparticles is demonstrated using liquid foams as templates. The foam is formed from an aqueous mixture of an anionic surfactant and the desired metal ions, where the metal ions are electrostatically entrapped by the surfactant at the thin borders between the foam bubbles and their junctions. The hydrolysis is carried out using alkali resulting in the formation of desired nanoparticles, with the foam playing the role of a template. However, in the formation of ferrites with the formula MFe2O4, where the metal ion and iron possess oxidation states of +2 and +3, respectively, forming a foam from a 1:2 mixture of the desired ionic solutions would lead to a foam composition at variance with the original solution mixture because of greater electrostatic binding of ions possessing a greater charge with the surfactant. In our procedure, we circumvent this problem by preparing the foam from a 1:2 mixture of M2+ and Fe2+ ions and then utilizing the in situ conversion of Fe2+ to Fe3+ under basic conditions inside the foam matrix to get the desired composition of the metal ions with the required oxidation states. The fact that we could prepare both CoFe2O4 and MgFe2O4 particles shows the vast scope of this method for making even multicomponent oxides. The magnetic nanoparticles thus obtained exhibit a good crystalline nature and are characterized by superparamagnetic properties. The magnetic features observed for CoFe2O4 and MgFe2O4 nanoparticles are well in accordance with the expected behaviors, with CoFe2O4 particles showing higher blocking temperatures and larger coercivities. These features can easily be explained by the contribution of Co2+ sites to the magnetocrystalline anisotropy and the absence of the same from the Mg2+ ions.

1 aBala, Tanushree1 aSankar, C., R.1 aBaidakova, Marina1 aOsipov, V.1 aEnoki, Toshiaki1 aJoy, Pattayil, Alias1 aPrasad, Bhagavatula L. V.1 aSastry, M. uhttps://library.ncl.res.in/content/cobalt-and-magnesium-ferrite-nanoparticles-preparation-using-liquid-foams-templates-and-002294nas 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

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.

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-001950nas a2200169 4500008004100000022001400041245006800055210006600123260008300189300001100272490000700283520132800290100002301618700002401641700002501665856009001690 2005 eng d a1098-012100aEffect of disorder on the magnetic properties of LaMn0.5Fe0.5O30 aEffect of disorder on the magnetic properties of LaMn05Fe05O3 aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMERICAN PHYSICAL SOCcAUG a0544260 v723 a

Polycrystalline LaMn0.5Fe0.5O3 is synthesized by a low-temperature method and the magnetic properties of the resulting powder have been studied after annealing the sample in air at different temperatures in the range 200 degrees C-1350 degrees C. Room temperature Mossbauer spectroscopic studies show that the Fe ions are present in the +3 oxidation state in the material. However, the magnetic properties vary widely in an unexpected manner when samples are annealed at different temperatures. Zero field cooled magnetization studies show a cusp below 100 K, for the sample annealed at 200 degrees C, indicating a spin-glass-like or superparamagnetic behavior. However, this cusp disappears completely when the sample is annealed at 700 degrees C but still showing a magnetic hysteresis loop with reduced magnetization at low temperatures. The cusp again appears when the sample is annealed at higher temperatures with increasing low-temperature magnetization. EPR and IR spectroscopic studies indicate changes in the distribution of Mn3+ and Fe3+ ions in the lattice. The overall results can be explained in terms of random distribution of Mn3+ and Fe3+ ions in the lattice and formation of some magnetic clusters, with the degree of distribution of the ions varying for samples annealed at different temperatures.

1 aBhame, Shekhar, D.1 aJoly, V., L. Joseph1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/effect-disorder-magnetic-properties-lamn05fe05o3-101551nas a2200193 4500008004100000022001400041245009000055210006900145260010600214300001200320490000800332520078800340653003501128653002301163653001901186100001801205700002501223856010901248 2005 eng d a0038-109800aElectronic structure and ferromagnetism of polycrystalline Zn1-xCoxO (0 <= x <= 0.15)0 aElectronic structure and ferromagnetism of polycrystalline Zn1xC aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUN a665-6690 v1343 a

The electronic structure of polycrystalline ferromagnetic Zn1-x,CoxO (0.05 <= x <= 0.15) and the oxidation state of Co in it, have been investigated. The Co-doped polycrystalline samples are synthesized by a combustion method and are ferromagnetic at room temperature. XPS and optical absorption studies show evidence for Co2+ ions in the tetrahedral symmetry, indicating, substitution of Co2+ in the ZnO lattice. However, powder XRD and electron diffraction data shock the presence of Co metal in the samples. This give evidence to the fact that some Co2+ ion are incorporated in the ZnO lattice which gives changes in the electronic structure whereas ferromagnetism comes from the Co metal impurities present in the samples. (c) 2005 Elsevier Ltd. All rights reserved.

10aMagnetically ordered materials10aOptical properties10aSemiconductors1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/electronic-structure-and-ferromagnetism-polycrystalline-zn1-xcoxo-0-001915nas a2200169 4500008004100000020001800041245010000059210006900159260009600228300001200324520119600336100001801532700002301550700002501573700001901598856012801617 2005 eng d a1-57498-218-400aHigh magnetic aspects of nanosized NiZn ferrite powders synthesized by an autocombustion method0 aHigh magnetic aspects of nanosized NiZn ferrite powders synthesi aSan Francisco, CAbAmer Ceramic Soc, 735 Ceramic Place, Westerville, OH 43081-8720 USAcAUG a149-1543 a

Nanocrystalline NiZn ferrite, Ni0.5Zn0.5Fe2O4, having particle size in the range 6-10 mn, has been synthesized by an auto-combustion method. The nanosized ferrite powder formed at a low temperature is annealed at different temperatures in the range 473-1273 K and characterized by X-ray diffraction, vibrating sample magnetometry, Mossbauer spectroscopy, transmission electron microscopy and scanning electron microscopy. Magnetic transition temperature broadening up to 773 K is observed for the nanosized sample, compared to the T-c = 563 K for the bulk material. Critical particle diameter (D-c) is found to be similar to 40 nm at which maximum coercivity is obtained for the powder sample annealed at 973 K. Similarly, high room temperature magnetization, comparable to that of the bulk material, is obtained for the powders annealed at 1073 K, with a maximum particle size of similar to 50 nm. Very little grain growth is observed for the powders annealed above 1073 K. The results show that, optimum magnetic properties can be achieved for fine particle NiZn ferrite powders synthesized by a low-temperature auto-combustion method and processed at relatively lower temperatures.

1 aDeka, Sasanka1 aDate, Sadgopal, K.1 aJoy, Pattayil, Alias1 aSoohoo, R., F. uhttps://library.ncl.res.in/content/high-magnetic-aspects-nanosized-nizn-ferrite-powders-synthesized-autocombustion-method-001328nas a2200253 4500008004100000022001400041245013400055210006900189260007300258300001400331490000700345520039400352653002500746653001200771653002000783653003000803653002300833653001800856100001400874700001600888700001600904700002500920856012900945 2005 eng d a0167-577X00aLow-temperature synthesis of nanocrystalline powders of lithium ferrite by an autocombustion method using citric acid and glycine0 aLowtemperature synthesis of nanocrystalline powders of lithium f aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP a2630-26330 v593 a

Nanocrystalline lithium ferrite is synthesized by an autocombustion method from the corresponding metal nitrates using citric acid as well as glycine as fuels. The ordered phase of lithium ferrite, in single phase form, with particle size of 32-36 nm and large coercivity, is obtained by this method at a low temperature of 200 degrees C. (c) 2005 Elsevier B.V. All rights reserved.

10aCombustion synthesis10aLiFe5O810alithium ferrite10alow-temperature synthesis10aMagnetic materials10aNanomaterials1 aVerma, S.1 aKarande, J.1 aPatidar, A.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/low-temperature-synthesis-nanocrystalline-powders-lithium-ferrite-autocombustion-method-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

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.

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-002286nas a2200217 4500008004100000020001800041245009800059210006900157260009600226300001200322520144500334100002001779700001801799700001401817700001901831700002201850700002501872700002301897700001901920856012901939 2005 eng d a1-57498-218-400aMagnetic properties of nanosized ferrite powders synthesized by microwave-hydrothermal method0 aMagnetic properties of nanosized ferrite powders synthesized by  aSan Francisco, CAbAmer Ceramic Soc, 735 Ceramic Place, Westerville, OH 43081-8720 USAcAUG a143-1483 a

Nanosized powders of Fe3O4 and MgFe2O4 are synthesized by microwave-hydrothermal (MH) method. The ferrite powders thus obtained are characterized by powder X-ray diffraction, Mossbauer spectroscopy, scanning and transmission electron microscopies, vibrating sample magnetometer and AC magnetic susceptibility studies. Stoichiometric, nanosized (similar to 34 nm) Fe3O4 particles, having cubic symmetry with a(0) approximate to 8.39 angstrom, are obtained when molar ratio of Fe/NaOH used for the synthesis is 0.133. On the other hand, non-stoichiometric Fe3O4 is obtained when Fe/NaOH molar ratio is increased to 0.4. Though the powder XRD patterns of both stoichiometric and non-stoichiometric Fe3O4 are identical, Mossbauer spectroscopic studies showed different features in terms of asymmetry, intensity, isomer shift, etc. Saturation magnetization, M-s = 70 emu/g and coercivity, H-c = 178 Oe, at room temperature, are obtained for stoichiometric Fe3O4 powders. In the case of MgFe2O4, spherical, nanosized (similar to 3 nm) powders with cubic symmetry (a(0) approximate to 8.30 angstrom) and having very narrow size distribution are obtained under the MH conditions. The temperature and field dependent magnetic measurements on MgFe2O4 powders confirmed the existence of superparamagnetic state in this material with a superparamagnetic blocking temperature of 38 K below which typical magnetic hysteresis behaviour is observed.

1 aKhollam, Y., B.1 aDhage, S., R.1 aVerma, S.1 aPotdar, H., S.1 aDeshpande, S., B.1 aJoy, Pattayil, Alias1 aDate, Sadgopal, K.1 aSoohoo, R., F. uhttps://library.ncl.res.in/content/magnetic-properties-nanosized-ferrite-powders-synthesized-microwave-hydrothermal-method-002195nas a2200157 4500008004100000022001400041245007300055210006900128260008300197300001100280490000700291520159200298100001901890700002501909856010301934 2005 eng d a1098-012100aMagnetic properties of the self-doped lanthanum manganites La1-xMnO30 aMagnetic properties of the selfdoped lanthanum manganites La1xMn aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMERICAN PHYSICAL SOCcJUL a0244050 v723 a

The magnetic properties of different compositions in the self-doped lanthanum manganites, La1-xMnO3, have been studied by ac susceptibility and dc magnetization measurements in the temperature range 10-300 K. All compositions with x < 0.125 show an anomalous decrease in the ac susceptibility and zero field cooled (ZFC) dc magnetization at low temperatures, below the ferromagnetic ordering temperature. The temperature below which this anomalous behavior is observed, T-a, varies with the degree of La vacancy in the series where the Mn4+ concentration decreases with increasing x. Moreover, T-a varies with the Mn4+ content for a given composition. However, in both cases, this temperature levels off when the concentration of Mn4+ is above 23%. The magnetic-transition-like feature broadens and shifts to further lower temperatures with increasing magnetic fields and vanishes when measured above a certain field. A small but drastic increase in the coercivity is observed below T-a. There is a direct correlation between the shapes of the curves of the inverse of the coercivity as a function of temperature and ac susceptibility, indicating the influence of magnetic anisotropy on the characteristics of the ac susceptibility and zero field cooled magnetization curves of the self-doped compounds. The direct correlation between the changes in the coercivity and ac susceptibility as well as ZFC magnetization when measured at low magnetic fields give evidence to the role of domain wall pinning effects, which varies with the degree of self-doping or Mn4+ concentration.

1 aSankar, C., R.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/magnetic-properties-self-doped-lanthanum-manganites-la1-xmno3-101461nas a2200193 4500008004100000022001400041245006200055210006100117260008100178300001400259490000700273520079500280100001401075700002001089700001701109700002001126700002501146856009601171 2005 eng d a0002-782000aNovel low-temperature synthesis of nanosized NiZn ferrite0 aNovel lowtemperature synthesis of nanosized NiZn ferrite a9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLANDbBLACKWELL PUBLISHINGcSEP a2597-25990 v883 a

Nanosized NiZn ferrite powder is synthesized by a low-temperature method, using a unique combination of citric acid and glycine. An appropriate molar ratio of both citric acid and glycine offers a low-temperature synthetic route by incorporating the complexation behavior of citric acid and the combustion nature of glycine. Thermal decomposition/controlled autocatalytic combustion of the composite gel occurs at a low temperature of around 175 degrees C, with the evolution of a large amount of gases. Transmission electron microscopic studies showed that the average particle size of the ferrite obtained is similar to 2.5 nm, with a narrow size distribution. Uniformly distributed fine-grained microstructure with low porosity is obtained for a sample sintered at 1000 degrees C.

1 aVerma, S.1 aPradhan, S., D.1 aPasricha, R.1 aSainkar, S., R.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/novel-low-temperature-synthesis-nanosized-nizn-ferrite-001164nas a2200157 4500008004100000022001400041245008200055210006900137260008300206300001100289490000700300520054200307100001900849700002500868856011300893 2005 eng d a1098-012100aSuperspin glass behavior of a nonstoichiometric lanthanum manganite LaMnO3.130 aSuperspin glass behavior of a nonstoichiometric lanthanum mangan aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMERICAN PHYSICAL SOCcOCT a1324070 v723 a

Aging and memory effects are observed in an oxygen nonstoichiometric lanthanum manganite LaMnO3.13 from time-dependent dc magnetic measurements by employing various cooling protocols. The results can be best described by the superspin glass model of interacting magnetic nanoparticles system. The possible origin of such a behavior is the confinement of interacting small magnetic clusters formed as a result of the formation of manganese vacancies, along with the random distribution of tetravalent manganese ions in the lattice.

1 aSankar, C., R.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/superspin-glass-behavior-nonstoichiometric-lanthanum-manganite-lamno313-101315nas a2200169 4500008004100000020001800041245007000059210006900129260010700198300001200305520063900317100001800956700002300974700002500997700001901022856010401041 2005 eng d a1-57498-218-400aSynthesis and magnetic properties of polycrystalline Co-doped ZnO0 aSynthesis and magnetic properties of polycrystalline Codoped ZnO aSan Francisco, CAbAmer Ceram Soc; Japan Soc Powder & Powder Met; Int Magnet Assoc; Amer Phys SoccAUG a913-9183 a

Nanocrystalline Zn1-xCoxO powders have been synthesized by a glycine-nitrate (GNP) and modified GNP methods. Ferromagnetism at room temperature and above is observed for the powder samples synthesized by GNP method. The saturation magnetization value at 300 K is obtained as 0.08 and 0.28 emu/g (at 1 T), respectively, for x = 0.05 and 0.1. Ferromagnetic transition occurs at 740 K and 770 K for the respective samples, which is much larger than that the reported in the literature for thin film samples. On the other hand, no ferromagnetism was observed, down to 10 K, for the compounds synthesized by the modified GNP method.

1 aDeka, Sasanka1 aDate, Sadgopal, K.1 aJoy, Pattayil, Alias1 aSoohoo, R., F. uhttps://library.ncl.res.in/content/synthesis-and-magnetic-properties-polycrystalline-co-doped-zno-001521nas a2200241 4500008004100000022001400041245009600055210006900151260007300220300001400293490000700307520065900314653002000973653002700993653001901020100001901039700001601058700001601074700002001090700002001110700002501130856012401155 2005 eng d a0167-577X00aSynthesis of chromium substituted nano particles of cobalt zinc ferrites by coprecipitation0 aSynthesis of chromium substituted nano particles of cobalt zinc  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV a3402-34050 v593 a

Nano particles of chromium substituted cobalt zinc ferrite have been synthesized by a chemical co-precipitation method. X-ray diffraction studies of the nano particles of CrxCo0.5-xZn0.5Fe2O4 (x = 0.1 to 0.5) heat-treated at 300 degrees C show that the particle sizes are in the range of 2 to 7 nm. Room temperature Fe-57 Mossbauer spectra of all the samples show only two doublets, confirming the presence of superparamagnetic relaxation in the nano particles. An exponential decrease in the superparamagnetic blocking temperature, with increasing chromium concentration, is observed for these samples. (C) 2005 Elsevier B.V. All rights reserved.

10aCo0.5Zn0.5Fe2O410aMossbauer spectroscopy10anano materials1 aSharma, R., K.1 aSuwalka, O.1 aLakshmi, N.1 aVenugopalan, K.1 aBanerjee, Abhik1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/synthesis-chromium-substituted-nano-particles-cobalt-zinc-ferrites-coprecipitation-001393nas a2200205 4500008004100000022001400041245009500055210006900150260006900219300001100288490000800299520063300307653002300940653002300963653002400986653001101010100001801021700002501039856012301064 2006 eng d a0254-058400aCharacterization of nanosized NiZn ferrite powders synthesized by an autocombustion method0 aCharacterization of nanosized NiZn ferrite powders synthesized b aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcNOV a98-1010 v1003 a

Nanocrystalline Ni0.5Zn0.5Fe2O4 with average particle size of similar to 9 nm has been synthesized by an autocombustion method and characterized by powder XRD, TEM and room temperature magnetic measurements. High room temperature magnetization comparable to that of the bulk material is obtained for the nanosized powders annealed at 800 degrees C, with a maximum particle size of similar to 54 nm. The results show that optimum properties can be achieved for NiZn ferrite powders synthesized by the present autocombustion method and processed at relatively lower temperatures. (c) 2005 Elsevier B.V. All rights reserved.

10aChemical synthesis10aMagnetic materials10amagnetic properties10aOxides1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/characterization-nanosized-nizn-ferrite-powders-synthesized-autocombustion-method-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

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.

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-001350nas a2200157 4500008004100000022001400041245008700055210006900142260012500211300002300336490000700359520065900366100002301025700002501048856011901073 2006 eng d a0021-897900aEnhanced magnetostrictive properties of Mn substituted cobalt ferrite Co1.2Fe1.8O40 aEnhanced magnetostrictive properties of Mn substituted cobalt fe aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScAPR aArticle No. 1079010 v993 a

The effect of substitution of Fe and Co by Mn on the magnetostrictive properties of the cobalt ferrite Co1.2Fe1.8O4 has been studied and compared. The studies on Co1.2-xMnxFe1.8O4 and Co1.2Fe1.8-xMnxO4 (0 <= x <= 0.4) showed a marked dependence of magnetostriction on the substitution of both Fe and Co by Mn. Higher magnetostriction is obtained for the substitution of Co by Mn whereas the magnetostriction is reduced substantially on the substitution of Fe by Mn. Higher magnetostriction at low magnetic fields and enhancement of the strain ratio have been observed for the substitution of Co by Mn. (c) 2006 American Institute of Physics.

1 aBhame, Shekhar, D.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhanced-magnetostrictive-properties-mn-substituted-cobalt-ferrite-co12fe18o4-102118nas 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

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.

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-001318nas a2200169 4500008004100000022001400041245016700055210006900222260008300291300002300374490000700397520056300404100001800967700001900985700002501004856011901029 2006 eng d a1098-012100aExperimental comparison of the structural, magnetic, electronic, and optical properties of ferromagnetic and paramagnetic polycrystalline Zn1-xCoxO (x=0,0.05,0.1)0 aExperimental comparison of the structural magnetic electronic an aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMERICAN PHYSICAL SOCcJUL aArticle No. 0332010 v743 a

Ferromagnetism at room temperature is observed in one case whereas paramagnetism down to 12 K is observed in the second case when polycrystalline Zn1-xCoxO is synthesized under almost identical conditions. Identical x-ray diffraction, optical absorption, and x-ray photoelectron spectroscopy results indicate the incorporation of Co2+ ions in the ZnO lattice in both cases. However, electron diffraction studies show the presence of Co metal impurities in the ferromagnetic samples, indicating that pure Co doped ZnO is not likely to be ferromagnetic.

1 aDeka, Sasanka1 aPasricha, Renu1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/experimental-comparison-structural-magnetic-electronic-and-optical-properties-101358nas a2200157 4500008004100000022001400041245008400055210006900139260012500208300002300333490000700356520068100363100001801044700002501062856011301087 2006 eng d a0003-695100aFerromagnetism induced by hydrogen in polycrystalline nonmagnetic Zn0.95Co0.05O0 aFerromagnetism induced by hydrogen in polycrystalline nonmagneti aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScJUL aArticle No. 0325080 v893 a

Polycrystalline Zn0.95Co0.05O is found to be paramagnetic at room temperature and down to 12 K. Optical measurements prove the incorporation of Co2+ ions inside the ZnO lattice in the tetrahedral site. When the paramagnetic sample is heated in Ar/H-2 at 1125 K for 2 h, ferromagnetism with a very high value of magnetization is observed at room temperature. Hydrogen reduction does not affect the substituted Co2+ ions inside the wurtzite crystal lattice as evidenced from optical studies. X-ray diffraction studies show the presence of Co metal after the reduction process which is the origin of room temperature ferromagnetism. (c) 2006 American Institute of Physics.

1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/ferromagnetism-induced-hydrogen-polycrystalline-nonmagnetic-zn095co005o-102014nas 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

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.

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-002344nas a2200289 4500008004100000022001400041245011300055210006900168260007300237300001200310490000800322520134400330653002101674653002201695653001601717653002401733653001801757100002001775700001701795700001401812700001601826700002101842700002501863700001901888700001801907856012901925 2006 eng d a0304-885300aModifications in magnetic anisotropy of M-type strontium hexaferrite crystals by swift heavy ion irradiation0 aModifications in magnetic anisotropy of Mtype strontium hexaferr aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a392-4020 v3053 a

Using vibrating sample magnetometery (VSM) 50 MeV Li(3+) ion irradiation effects on magnetic properties of single crystals of SrGa(x)In(y)Fe(12-(x+y))O(19) (where x = 0, 5, 7, 9; y = 0, 0.8, 1.3, 1.0), are reported. The substitution of Ga and In in strontium hexaferrite crystals decreases the value of magnetization sharply, which is attributed to shifting of collinear magnetic order to a non-collinear one. Reduction of magnetization is also explained to be as a result of the occupation of the crystallographic sites of Fe(3+) by Ga(3+) and In(3+). The Li(3+) ion irradiation decreases the value of magnetization, irrespective of whether the crystals are Ga-In substituted or unsubstituted crystals of SrFe(12)O(19). The result is interpreted in terms of the occurrence of a paramagnetic doublet in crystals replacing magnetic sextuplet as a result of irradiation. Substitution of Ga-In in Strontium hexaferrite decreases the value of anisotropy constant. Irradiation with Li(3+) ions increases the values of anisotropy field for both substituted as well as unsubstituted crystals. Substitution with Ga-In also decreases the Curie temperature (T(c)) but the irradiation with Li(3+) ions does not affect the curie temperature of either Ga-In substituted or pure SrFe(12)O(19) crystals. (C) 2006 Elsevier B.V. All rights reserved.

10aanisotropy field10aCurie temperature10airradiation10aMagnetic anisotropy10aMagnetization1 aKaur, Balwinder1 aBhat, Monita1 aLicci, F.1 aKumar, Ravi1 aKulkarni, S., D.1 aJoy, Pattayil, Alias1 aBamzai, K., K.1 aKotru, P., N. uhttps://library.ncl.res.in/content/modifications-magnetic-anisotropy-m-type-strontium-hexaferrite-crystals-swift-heavy-ion-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

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.

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-001474nas a2200241 4500008004100000022001400041245008600055210006900141260007300210300001200283490000800295520063300303653002400936653001400960653001800974653002300992653000801015100001801023700001801041700002501059700002801084856012001112 2006 eng d a0304-885300aSize-dependent magnetic properties of nanocrystalline yttrium iron garnet powders0 aSizedependent magnetic properties of nanocrystalline yttrium iro aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUN a212-2190 v3013 a

Yttrium iron garnet (YIG) powders with particle sizes of 9, 14, 25 and 60 nm have been synthesised and their magnetic properties have been studied as a function of particle size and temperature. The particles with sizes of 9 and 14 nm exhibited superparamagnetism. The blocking temperature (T-B) decreased with decreasing particle size, whereas the anisotropy constant (K) increased. The saturation magnetisation (M-s) decreased with decreasing particle size. These variations are attributed to large surface-to-volume ratios in nanoparticles where the surface moments are predominant. (c) 2005 Published by Elsevier B.V.

10aanisotropy constant10aMagnetism10aNanoparticles10aSuperparamagnetism10aYIG1 aRajendran, M.1 aDeka, Sasanka1 aJoy, Pattayil, Alias1 aBhattacharya, Asish, K. uhttps://library.ncl.res.in/content/size-dependent-magnetic-properties-nanocrystalline-yttrium-iron-garnet-powders-001256nas a2200157 4500008004100000022001400041245008300055210006900138260012500207300001100332490000800343520059600351100002300947700002500970856010300995 2006 eng d a0021-897900aTuning of the magnetostrictive properties of CoFe2O4 by Mn substitution for Co0 aTuning of the magnetostrictive properties of CoFe2O4 by Mn subst aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScDEC a1139110 v1003 a

Marked changes in the magnetostriction of CoFe2O4 in the substitution of Mn for Co has been observed. The magnetostriction parallel to the applied field direction decreases with increasing Mn content, whereas the magnetostriction perpendicular to the field showed a marked increase for 10% of the Mn substitution. The observed magnetostrictive properties are correlated with the magnetic properties. The results suggest the possibility of tuning the magnetostrictive properties of cobalt ferrite for various applications by proper substitution. (c) 2006 American Institute of Physics.

1 aBhame, Shekhar, D.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/tuning-magnetostrictive-properties-cofe2o4-mn-substitution-co-101322nas 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

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.

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-nanoparticles01417nas a2200157 4500008004100000022001400041245012500055210006900180260006700249300001400316490000700330520074800337100001801085700002501103856013101128 2007 eng d a0002-782000aEnhanced permeability and dielectric constant of NiZn ferrite synthesized in nanocrystalline form by a combustion method0 aEnhanced permeability and dielectric constant of NiZn ferrite sy a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcMAY a1494-14990 v903 a

The performance parameters of Ni0.5Zn0.5Fe2O4, synthesized in the nanocrystalline form by an autocombustion method, have been investigated. The sample sintered at 1200 degrees C, with Bi2O3 as additive shows a very high value of initial permeability mu'(i) of > 400 at 1 MHz, with low loss. Similarly, a very high dielectric constant is obtained at lower frequencies. The results show that optimum magnetic and electrical properties can be achieved for the NiZn ferrite nanocrystalline powders synthesized by the present autocombustion method and sintered at a relatively lower temperature of 1200 degrees C when compared with a temperature of 1400 degrees C required for the materials synthesized by the conventional ceramic method.

1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhanced-permeability-and-dielectric-constant-nizn-ferrite-synthesized-nanocrystalline-form00946nas a2200157 4500008004100000022001400041245008600055210006900141260011000210300001200320490000700332520029700339100001800636700002500654856010900679 2007 eng d a0959-942800aEnhancement of the phase transformation temperature of gamma-Fe2O3 by Zn2+ doping0 aEnhancement of the phase transformation temperature of gammaFe2O aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJAN a453-4560 v173 a

The phase transformation temperature of gamma-Fe2O3 to alpha-Fe2O3 is increased with Zn2+ doping and enhancement of the transition temperature by similar to 100 degrees C is obtained for doping of >= 15 mol% Zn in nanocrystalline gamma-Fe2O3 synthesized by an autocombustion method.

1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhancement-phase-transformation-temperature-gamma-fe2o3-zn2-doping-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

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.

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-deviation01315nas a2200217 4500008004100000022001400041245012200055210006900177260007100246300001600317490000700333520048100340100002000821700001800841700002000859700002500879700002100904700001900925700003000944856012300974 2007 eng d a0743-746300aMultiutility sophorolipids as nanoparticle capping agents: synthesis of stable and water dispersible Co nanoparticles0 aMultiutility sophorolipids as nanoparticle capping agents synthe a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV a11409-114120 v233 a

Sophorolipids are a class of glycolipids that can be obtained from fatty acids by simply treating them with yeast cells (Candida bombicola, ATCC 22214) and glucose. In this letter, we demonstrate the application of sophorolipids obtained from oleic acid as a capping agent for Co nanoparticles. Upon capping the nanoparticle surface, the sugar moiety of these sophorolipids is exposed to the solvent environment, making the nanoparticles stable and water-redispersible.

1 aKasture, Manasi1 aSingh, Sanjay1 aPatel, Pitamber1 aJoy, Pattayil, Alias1 aPrabhune, Asmita1 aRamana, C., V.1 aPrasad, Bhagavatula L. V. uhttps://library.ncl.res.in/content/multiutility-sophorolipids-nanoparticle-capping-agents-synthesis-stable-and-water-001815nas a2200205 4500008004100000022001400041245006400055210006400119260010600183300001200289490000800301520106000309653002501369653003501394653002401429653001701453100001801470700002501488856009601513 2007 eng d a0038-109800aSynthesis and magnetic properties of Mn doped ZnO nanowires0 aSynthesis and magnetic properties of Mn doped ZnO nanowires aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAPR a190-1940 v1423 a

Mn doped ZnO nanowires have been synthesized using a simple autocombustion method. The as-synthesized Mn doped ZnO nanowires were characterized by X-ray diffraction and transmission electron microscopy. An increase in the hexagonal lattice parameters of ZnO is observed on increasing the Mn concentration. Optical absorption studies show an increment in the band gap with increasing Mn content, and also give evidence for the presence of Mn2+ ions in tetrahedral sites. All Zn1-xMnxO (0 <= x <= 0.25) samples are paramagnetic at room temperature. However, a large increase in the magnetization is observed below 50 K. This behavior, along with the negative value of the Weiss constant obtained from the linear fit to the susceptibility data below room temperature, indicate ferrimagnetic behavior. The origin of ferrimagnetism is likely to be either the intrinsic characteristics of the Mn doped samples, or due to some spinel-type impurity phases present in the samples that could not be detected. (c) 2007 Elsevier Ltd. All rights reserved.

10aCombustion synthesis10adiluted magnetic semiconductor10amagnetic properties10aMn doped ZnO1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/synthesis-and-magnetic-properties-mn-doped-zno-nanowires01417nas a2200157 4500008004100000022001400041245010700055210006900162260008100231300001400312490000700326520074700333100002301080700002501103856013101128 2008 eng d a0002-782000aEffect of sintering conditions and microstructure on the magnetostrictive properties of cobalt ferrite0 aEffect of sintering conditions and microstructure on the magneto a9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLANDbBLACKWELL PUBLISHINGcJUN a1976-19800 v913 a

The effects of sintering temperature and dwell time on the magnetostrictive properties of polycrystalline cobalt ferrite synthesized by the conventional ceramic method have been investigated. The present study showed that the magnitude of magnetostriction strongly depends on the microstructure of the final sintered product. The presence of small and uniform grains with less porous structure in the sintered material leads to enhancement of the magnetostrictive strain. Higher magnetostriction is obtained for samples sintered at a relatively lower temperature of 1100 degrees C. These results are further corroborated by analyzing the effect of some additives during sintering on the microstructural and magnetostrictive properties.

1 aBhame, Shekhar, D.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/effect-sintering-conditions-and-microstructure-magnetostrictive-properties-cobalt-ferrite-002072nas 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

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.

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-001081nas a2200205 4500008004100000022001400041245011600055210006900171260008400240300001200324490000700336520024600343100002600589700002800615700002100643700002500664700002500689700002900714856013200743 2008 eng d a0366-702200aHighly active nanostructured Co3O4 catalyst with tunable selectivity for liquid phase air oxidation of p-cresol0 aHighly active nanostructured Co3O4 catalyst with tunable selecti a1-5 KANDA-SURUGADAI CHIYODA-KU, TOKYO, 101-8307, JAPANbCHEMICAL SOC JAPANcMAR a310-3110 v373 a

This is a first report of highly efficient heterogeneous nanostructured Co3O4 catalyst (6-8 nm) having high surface area (95 m(2)/g) developed for selective liquid phase air oxidation of p-cresol under atmospheric pressure conditions.

1 aKshirsagar, Vikas, S.1 aVijayanand, Subramanian1 aPotdar, Hari, S.1 aJoy, Pattayil, Alias1 aPatil, Kashinath, R.1 aRode, Chandrashekhar, V. uhttps://library.ncl.res.in/content/highly-active-nanostructured-co3o4-catalyst-tunable-selectivity-liquid-phase-air-oxidation-001743nas a2200265 4500008004100000022001400041245015200055210006900207260007900276300001100355490000700366520078000373100001501153700001101168700001801179700002401197700002501221700002201246700001201268700001501280700001701295700001701312700001801329856013001347 2008 eng d a1098-012100aLocal electronic structure and magnetic properties of LaMn(0.5)Co(0.5)O(3) studied by x-ray absorption and magnetic circular dichroism spectroscopy0 aLocal electronic structure and magnetic properties of LaMn05Co05 aONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USAbAMER PHYSICAL SOCcMAR a1251240 v773 a

We have studied the local electronic structure of LaMn(0.5)Co(0.5)O(3) using soft-x-ray absorption spectroscopy at the Co-L(3,2) and Mn-L(3,2) edges. We found a high-spin Co(2+)-Mn(4+) valence state for samples with the optimal Curie temperature. We discovered that samples with lower Curie temperatures contain low-spin nonmagnetic Co(3+) ions. Using soft-x-ray magnetic circular dichroism, we established that the Co(2+) and Mn(4+) ions are ferromagnetically aligned. We also revealed that the Co(2+) ions have a large orbital moment: morb/mspin approximate to 0.47. Together with model calculations, this suggests the presence of a large magnetocrystalline anisotropy in the material and predicts a nontrivial temperature dependence for the magnetic susceptibility.

1 aBurnus, T.1 aHu, Z.1 aHsieh, H., H.1 aJoly, V., L. Joseph1 aJoy, Pattayil, Alias1 aHaverkort, M., W.1 aWu, Hua1 aTanaka, A.1 aLin, H., -J.1 aChen, C., T.1 aTjeng, L., H. uhttps://library.ncl.res.in/content/local-electronic-structure-and-magnetic-properties-lamn05co05o3-studied-x-ray-absorption-001815nas a2200217 4500008004100000022001400041245010800055210006900163260010600232300001400338490000700352520096600359653002301325653002301348653002401371653001901395653001101414100001701425700002501442856013001467 2008 eng d a0025-540800aLow temperature synthesis of nanocrystalline lithium ferrite by a modified citrate gel precursor method0 aLow temperature synthesis of nanocrystalline lithium ferrite by  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcDEC a3447-34560 v433 a

Single phase nanocrystalline lithium ferrite is synthesized by a modified citrate gel precursor technique. Ferrite nanoparticles of average size of 8 nm, obtained after calcination of the citrate gel Made by the usual method at 450 degrees C, show superparamagnetic behavior. However, small amounts of alpha-Fe(2)O(3) is formed as an impurity phase clue to the initial formation of some gamma-Fe(2)O(3) phase. Oil the other hand, when the pH of the mixed Solution is increased to 7 after the addition of ammonia Solution, a lower calcination temperature of 200 degrees C is sufficient for the formation of single phase lithium ferrite nanoparticles of size 30 nm. No impurity phases are detected when the nanocrystalline powders arc calcined at higher temperatures. The magnetic properties of the ferrite nanoparticles of different sizes obtained by calcining the powders at different temperatures are studied. (C) 2008 Elsevier Ltd. All rights reserved.

10aChemical synthesis10aMagnetic materials10amagnetic properties10aNanostructures10aOxides1 aVerma, Seema1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/low-temperature-synthesis-nanocrystalline-lithium-ferrite-modified-citrate-gel-precursor-001727nas 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

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.

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-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

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.

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-002173nas a2200193 4500008004100000022001400041245012500055210006900180260007100249300001600320490000800336520139700344100001501741700001901756700001701775700003201792700002501824856013001849 2008 eng d a1932-744700aSize dependent coordination behavior and cation distribution in MgAl2O4 nanoparticles from Al-27 solid state NMR studies0 aSize dependent coordination behavior and cation distribution in  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a14737-147440 v1123 a

Nanoparticles of spinel-type oxides such as ferrites offer great advantages and applications in many important areas. Decreasing the size of the particles to nanometer size will increase the surface-to-volume ratio and this will strongly influence the physical and chemical properties of these materials. For magnetic nanoparticles, the exchange interactions at the surface of a particle will be different from those inside due to changes in the coordination behavior at the surface. Therefore, studying and understanding the coordination and distribution behavior of the different metal ions in the nanoparticles of spinel-type oxides is very important. Solid state NMR is a useful and important technique to obtain information on local structural variations. The degree of the distribution of the Al3+ ions in the tetrahedral and octahedral sites in the nanoparticles of the nonmagnetic spinet MgAl2O4 having different particle sizes has been determined by Al-27 magic-angle spinning (MAS) NMR spectroscopy. It has been observed that the inversion parameter decreases with increasing particle size. Apart from the usual tetrahedral and octahedral coordinations present in the bulk material, the presence of five- and three-coordinated At has been observed in nanoparticles with sizes less than 18 nm and a second octahedral coordination is observed for nanoparticles of larger sizes.

1 aSreeja, V.1 aSmitha, T., S.1 aNand, Deepak1 aAjithkumar, Thalasseril, G.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/size-dependent-coordination-behavior-and-cation-distribution-mgal2o4-nanoparticles-al-27-001416nas a2200205 4500008004100000022001400041245008100055210006900136260009500205300001400300490000600314520065400320653002200974653002000996653002301016653001701039100001801056700002501074856011101099 2008 eng d a1533-488000aSuperparamagnetic nanocrystalline ZnFe2O4 with a very high curie temperature0 aSuperparamagnetic nanocrystalline ZnFe2O4 with a very high curie a25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USAbAMER SCIENTIFIC PUBLISHERScAUG a3955-39580 v83 a

Studies on the magnetic properties of nanocrystalline ZnFe2O4 synthesized by an autocombustion method are reported. Superparamagnetic behavior is observed for the nanocrystalline materials with particle sizes of 8 nm and 17 nm, with superparamagnetic blocking temperatures of 65 K and 75 K, respectively. Magnetic hysteresis with very large coercivities of 533 Oe and 325 Oe, respectively, are observed at 12 K. Studies on the temperature variation of the magnetization above room temperature indicate that the Curie temperature is as high as similar to 800 K when compared to the paramagnetic nature of bulk zinc ferrite at room temperature.

10aCurie temperature10aNanocrystalline10aSuperparamagnetism10aZinc Ferrite1 aDeka, Sasanka1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/superparamagnetic-nanocrystalline-znfe2o4-very-high-curie-temperature-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

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.

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-001481nas a2200217 4500008004100000022001400041245006600055210006600121260010600187300001400293490000800307520069700315653002301012653001801035653002401053653001801077100002501095700001801120700002501138856010001163 2009 eng d a0038-109800aFerromagnetic properties of glucose coated Cu2O nanoparticles0 aFerromagnetic properties of glucose coated Cu2O nanoparticles aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcDEC a2199-22010 v1493 a

Magnetic properties of glucose coated cuprous oxide nanoparticles of different sizes have been studied. Unlike bulk Cu2O, which shows diamagnetic behavior, the nanoparticles show superparamagnetic behavior. A superparamagnetic blocking temperature of 21 K is observed for 5 nm particles. A magnetic hysteresis loop with a coercivity of 406 Oe is observed for these particles at 5 K. The magnetization and the coercivity increase with decreasing particle size. The superparamagnetic behavior, along with the increase in magnetization and coercivity with decreasing particle size, is due to the enhanced surface contributions to the magnetism. (C) 2009 Elsevier Ltd. All rights reserved.

10aChemical synthesis10aCuprous oxide10amagnetic properties10aNanoparticles1 aMahajan, Mangesh, B.1 aPavan, M., S.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/ferromagnetic-properties-glucose-coated-cu2o-nanoparticles-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

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 <= x <= 0.125, indicating that the ferromagnetic to spin glass cross over is not abrupt. (C) 2008 Elsevier Masson SAS. All rights reserved.

10aFerromagnetism10aMagnetic clusters10aManganites10aperovskite10aSpin glass1 aSankar, Raj1 aVijayanand, S.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/ferromagnetic-spin-glass-cross-over-latb23ca13mno3-002159nas 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

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.

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-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

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.

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-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

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.

10adielectric constant10amanganite10aMultiferroic1 aSagar, S.1 aJoy, Pattayil, Alias1 aAnantharaman, Maliemadom, R. uhttps://library.ncl.res.in/content/multiferroic-behavior-gd-based-manganite-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

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.

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-bifeo3-001562nas a2200241 4500008004100000022001400041245010800055210006900163260009200232300001200324490000600336520069000342653001501032653001201047653002401059653001801083653002001101653001701121100001801138700002501156700002001181856011901201 2009 eng d a1947-293500aSingle step synthesis and properties of M/MFe2O4 and PVDF/M/MFe2O4 (M = Co, Ni) magnetic nanocomposites0 aSingle step synthesis and properties of MMFe2O4 and PVDFMMFe2O4  a26650 THE OLD RD, STE 208, VALENCIA, CA 91381-0751 USAbAMER SCIENTIFIC PUBLISHERScDEC a262-2680 v13 a

Metal/ferrite nanocomposites (M/MFe2O4; M = Co, Ni), consisting of nanoparticles of a metal and the corresponding metal ferrite, have been synthesized under in situ conditions by a simple and single step process. The metal/ferrite nanocomposites embedded in a polymer matrix have been prepared by a simple hot-pressing method. The performance parameters such as magnetization, coercivity, permeability and dielectric constant of the two- and three-phase nanocomposite systems are compared. The coercivity increases and the permeability decreases with increasing polymer content in the three-phase composite. Enhancement of the dielectric constant is observed at low frequencies.

10aDielectric10aFerrite10amagnetic properties10aNanocomposite10aNanocrystalline10apermeability1 aDeka, Sasanka1 aJoy, Pattayil, Alias1 aKumar, Pratheep uhttps://library.ncl.res.in/content/single-step-synthesis-and-properties-mmfe2o4-and-pvdfmmfe2o4-m-co-ni-magnetic-001799nas a2200229 4500008004100000022001400041245009900055210006900154260007400223300001200297490000700309520099100316653001901307653001901326653002501345653001401370653000801384100001401392700001901406700002501425856011901450 2009 eng d a1388-076400aSolid state synthesis and room temperature magnetic properties of iron phosphide nanoparticles0 aSolid state synthesis and room temperature magnetic properties o aVAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDSbSPRINGERcFEB a491-4970 v113 a

Room temperature magnetic properties have been achieved for nano-crystalline iron phosphide synthesized from the direct solid state reaction of iron chloride and tri-octylphosphine (TOP). The magnetization continuously increased with higher magnetic fields, indicating a super-paramagnetic behavior. It is observed that room temperature magnetism is possible for the material showing antiferromagnetic nature at low temperatures. In the present synthesis, TOP acted as a source of phosphorus as well as a surfactant. X-ray diffraction (XRD) studies revealed that the black powder is a mixture of FeP and Fe(2)P. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed elongated as well spherical particles. Energy dispersion X-ray analysis (EDAX) confirmed a non-stoichiometric iron phosphide. Presence of TOP was confirmed by infra-red (IR) spectroscopy, and thermo-gravimetric analysis (TGA) indicated about 6% wt. loss due to presence of organics.

10aIron phosphide10aSemiconductors10aSolid state reaction10asynthesis10aXRD1 aSingh, N.1 aKhanna, P., K.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/solid-state-synthesis-and-room-temperature-magnetic-properties-iron-phosphide-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

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.

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-001446nas a2200205 4500008004100000022001400041245010700055210006900162260009500231300001200326490000600338520063300344653002400977653001801001653002301019653002301042100002101065700002501086856012901111 2009 eng d a1941-490000aSuperparamagnetic nanocomposite of magnetite and activated carbon for removal of dyes from waste water0 aSuperparamagnetic nanocomposite of magnetite and activated carbo a25650 NORTH LEWIS WAY, STEVENSON RANCH, CA 91381-1439 USAbAMER SCIENTIFIC PUBLISHERScDEC a171-1750 v13 a

Nanocomposite of superparamagnetic Fe(3)O(4) and activated carbon (AC) is synthesized at room temperature and characterized by various techniques. Magnetic measurements indicated that the Fe(3)O(4) nanoparticles are isolated by the AC particles. The magnetic fluid obtained by dispersion of the nanocomposite in water is found to be relatively stable. The dispersion is found to be very efficient for the removal of methylene blue dye from water. Thus, the nanocomposite is highly suitable for removing dissolved dyes and other contaminants from waste water by a simple magnetic separation process after adsorption on AC.

10aMagnetic Separation10aNanocomposite10aSuperparamagnetism10aWater Purification1 aThakuria, Pankaj1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/superparamagnetic-nanocomposite-magnetite-and-activated-carbon-removal-dyes-waste-water-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

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.

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

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

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-001993nas a2200265 4500008004100000022001400041245013600055210006900191260010600260300001200366490000800378520095700386653002001343653001001363653003101373653002401404100002101428700002301449700002001472700002301492700002901515700003201544700002501576856012601601 2010 eng d a0038-109800aEvidence for the co-existence of distorted tetrahedral and trigonal bipyramidal aluminium sites in SrAl12O19 from Al-27 NMR studies0 aEvidence for the coexistence of distorted tetrahedral and trigon aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJAN a262-2660 v1503 a

Strontium aluminate, SrAl12O19, is a ceramic material having the hexagonal magnetoplumbite-type structure, with multiple Al coordination environments. An earlier low-field Al-27 solid-state NMR study reported five different Al sites in this system: one AlO4, one AlO5, and three AlO6 sites; whereas a later high-field study showed that the AlO5 site is a distorted AlO4 site with a very large quadrupolar coupling constant (similar to 20 MHz). Our magic angle spinning (MAS) and 3-quantum magic angle spinning (3QMAS) NMR studies at 7.05 T unambiguously show evidence for an AlO5 site. However, evidence for the presence of a distorted AlO4 site is obtained from studies at high fields (16.4 and 17.6 T), in addition to the AlO5 site. Thus the present solid-state NMR studies give evidence for the simultaneous presence of both the five-coordinated and distorted four-coordinated sites in this system. (C) 2009 Elsevier Ltd. All rights reserved.

10aLocal structure10aMQMAS10aNuclear magnetic resonance10aStrontium aluminate1 aHarindranath, K.1 aViswanath, Anusree1 aChandran, Vinod1 aBraeuniger, Thomas1 aMadhu, Perunthiruthy, K.1 aAjithkumar, Thalasseril, G.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/evidence-co-existence-distorted-tetrahedral-and-trigonal-bipyramidal-aluminium-sites-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

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.

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-001483nas a2200157 4500008004100000022001400041245008800055210006900143260012500212300001100337490000700348520080200355100002101157700002501178856012201203 2010 eng d a0003-695100aHigh room temperature ferromagnetic moment of Ho substituted nanocrystalline BiFeO30 aHigh room temperature ferromagnetic moment of Ho substituted nan aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScOCT a1625040 v973 a

Magnetic properties of trivalent rare-earth ion substituted nanocrystalline BiFeO3 have been studied for the compositions Bi0.875R0.125FeO3 (R=La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb). All compositions show ferromagnetic characteristics at room temperature, with enhanced magnetization after substitution. Very high magnetization (at 6 T), almost three times that of the unsubstituted composition, is observed for R=Ho, and highest remnant magnetization is obtained for R=Nd and Sm. The magnetic transition temperature is increased by similar to 20 K for R=La. The results show that it is possible to tune the magnetic characteristics of the nanocrystalline multiferroic BiFeO3 by the choice of the rare-earth ion. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3502481]

1 aThakuria, Pankaj1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/high-room-temperature-ferromagnetic-moment-ho-substituted-nanocrystalline-bifeo3-001979nas a2200265 4500008004100000022001400041245007500055210006900130260007300199300001000272490000700282520111500289653001401404653001901418653001001437653003001447653000801477653000801485100001901493700001801512700002801530700002501558700002101583856010901604 2010 eng d a0039-914000aHighly sensitive and fast responding CO sensor based on Co3O4 nanorods0 aHighly sensitive and fast responding CO sensor based on Co3O4 na aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR a37-430 v813 a

Co3O4 nanorods (diameters similar to 6-8 nm and lengths similar to 20-30 nm) were synthesized for the first time through a simple co-precipitation/digestion method by calcination of cobalt hydroxyl carbonate in air and their CO gas sensing properties were investigated. The Co3O4 nanorods exhibited outstanding gas sensing characteristics such as, higher gas response (similar to 6.55-50 ppm CO gas at 250 degrees C), extremely rapid response (similar to 3-4s), fast recovery (similar to 5-6s), excellent repeatability, good selectivity and lower operating temperature (similar to 250 degrees C). Furthermore, the Co3O4 nanorods are able to detect up to 5 ppm for CO with reasonable sensitivity (similar to 3.32) at an operating temperature 250 degrees C and they can be reliably used to monitor the concentration of CO over the range (5-50 ppm). The experimental results clearly demonstrate the potential of using the Co3O4 nanorods as sensing material in the fabrication of CO sensors. Plausible CO sensing mechanism of the Co3O4 nanorods is also discussed. (C) 2009 Elsevier B.V. All rights reserved.

10aCO sensor10aCo3O4 nanorods10aHRTEM10aSemiconductor gas sensors10aXPS10aXRD1 aPatil, Dewyani1 aPatil, Pradip1 aSubramanian, Vijayanand1 aJoy, Pattayil, Alias1 aPotdar, Hari, S. uhttps://library.ncl.res.in/content/highly-sensitive-and-fast-responding-co-sensor-based-co3o4-nanorods-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

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.

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

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.

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

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.

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-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

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.

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-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

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.

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

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.

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-001912nas a2200217 4500008004100000022001400041245012300055210006900178260013200247300001200379490000600391520102900397653002001426653002601446653002401472653001401496653001801510100001501528700002501543856012601568 2011 eng d a1475-743500aEffect of inter-particle interactions on the magnetic properties of magnetite nanoparticles after coating with dextran0 aEffect of interparticle interactions on the magnetic properties  aWORLD TRADE CENTER BLDG, 29 ROUTE DE PRE-BOIS, CASE POSTALE 896, CH-1215 GENEVA, SWITZERLANDbINDERSCIENCE ENTERPRISES LTDcJAN a907-9150 v83 a

Nanoparticles of magnetite (Fe3O4) are synthesised by a coprecipitation method and coated with the biocompatible polymer, dextran. The uncoated and dextran coated magnetite nanoparticles are characterised by powder X-ray diffraction, infrared spectroscopy, transmission electron microscopy, and magnetic measurements. The magnetic properties of the uncoated and coated magnetite nanoparticles are compared to study the effect of inter-particle magnetic interactions on the magnetic characteristics. Absence of magnetic hysteresis at room temperature indicates the superparamagnetic nature of the two samples. Evidence for the effect of reduced inter-particle magnetic interactions is directly obtained from the field dependence of magnetisation at room temperature. The decreased superparamagnetic blocking temperature and the nature and shape of the field cooled magnetisation curve of the dextran coated sample further confirmed that the inter-particle magnetic interactions are completely suppressed after coating.

10adextran coating10amagnetic interactions10amagnetic properties10amagnetite10aNanoparticles1 aSreeja, V.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/effect-inter-particle-interactions-magnetic-properties-magnetite-nanoparticles-after-002511nas a2200265 4500008004100000022001400041245010000055210006900155260007600224300001400300490000800314520159500322653001401917653002201931653001901953653001701972653001901989100002002008700001802028700001902046700001702065700002502082700001702107856012102124 2011 eng d a0021-899500aMagnetic and electric responsive hydrogel-magnetic nanocomposites for drug-delivery application0 aMagnetic and electric responsive hydrogelmagnetic nanocomposites aCOMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USAbWILEY-BLACKWELLcOCT a1364-13750 v1223 a

Magnetic and electrically responsive hydrogel networks were developed for drug-delivery applications. The hydrogel matrices were synthesized by the polymerization of acrylamide monomer in the presence of carboxymethylcellulose (CMC) or methylcellulose (MC) with N,N-methylenebisacrylamide, a crosslinker with the redox initiating system ammonium persulfate/tetramethylethylenediamine. The magnetic nanoparticles were generated throughout these hydrogel matrices by an in situ method by the incorporation of iron ions and their subsequent reduction with ammonia. A series of hydrogel-magnetic nanocomposites (HGMNCs) were developed with various CMC and MC compositions. The synthesized HGMNCs were characterized with spectral (Fourier transform infrared and ultraviolet-visible spectroscopy), X-ray diffraction, thermal, and microscopy methods. These HGMNCs contained iron oxide (Fe3O4) nanoparticles with an average particle size of about 22 nm, as observed by transmission electron microscopy. The dielectrical properties of the pure hydrogel (HG); the hydrogel loaded with iron ions, or the hydrogel iron-ion composite (HGIC); and the HGMNCs were measured. These results suggest that HGMNCs exhibited higher dielectric constants compared to HG and HGICs. The curcumin loading and release characteristics were also measured for HG, HGIC, and HGMNC systems. These data revealed that there was a sustained release of curcumin from HGMNCs because of the presence of magnetic nanoparticles in the hydrogel networks. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 1364-1375, 2011

10ahydrogels10amagnetic polymers10aNanocomposites10ananoparticle10ananotechnology1 aReddy, Narayana1 aMohan, Murali1 aVaraprasad, K.1 aRavindra, S.1 aJoy, Pattayil, Alias1 aRaju, Mohana uhttps://library.ncl.res.in/content/magnetic-and-electric-responsive-hydrogel-magnetic-nanocomposites-drug-delivery-002164nas a2200253 4500008004100000022001400041245005900055210005900114260006900173300001200242490000800254520136200262653001001624653001501634653002701649653003001676653000801706100002801714700002501742700002101767700001901788700001801807856008501825 2011 eng d a0925-400500aNanostructured spinet ZnCo2O4 for the detection of LPG0 aNanostructured spinet ZnCo2O4 for the detection of LPG aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcFEB a121-1290 v1523 a

Nanostrucutred spinel ZnCo2O4 (similar to 26-30 nm) was synthesized by calcining the mixed precursor (consisting of cobalt hydroxyl carbonate and zinc hydroxyl carbonate) in air at 600 degrees C for 5 h. The mixed precursor was prepared through a low cost and simple co-precipitation/digestion method. The transformation of the mixed precursor into nanostructured spinel ZnCO2O4 upon calcinations was confirmed by X-ray diffraction (XRD) measurement, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM). To demonstrate the potential applicability of ZnCo2O4 spinel in the fabrication of gas sensors, its LPG sensing characteristics were systematically investigated. The ZnCo2O4 spinel exhibited outstanding gas sensing characteristics such as, higher gas response (similar to 72-50 ppm LPG gas at 350 degrees C), response time (similar to 85-90 s), recovery time (similar to 75-80 s), excellent repeatability, good selectivity and relatively lower operating temperature (similar to 350 degrees C). The experimental results demonstrated that the nanostructured spinel ZnCo2O4 is a very promising material for the fabrication of LPG sensors with good sensing characteristics. Plausible LPG sensing mechanism is also discussed. (c) 2010 Elsevier B.V. All rights reserved.

10aHRTEM10aLPG sensor10aNanostructured ZnCo2O410aSemiconductor gas sensors10aXPS1 aVijayanand, Subramanian1 aJoy, Pattayil, Alias1 aPotdar, Hari, S.1 aPatil, Dewyani1 aPatil, Pradip uhttps://library.ncl.res.in/content/nanostructured-spinet-znco2o4-detection-lpg-001583nas a2200217 4500008004100000022001400041245010700055210006900162260006900231300001400300490000800314520075500322653002301077653001801100653002701118653002901145100001701174700002501191700001901216856013001235 2011 eng d a0925-838800aStructural, magnetic and mossbauer spectral studies of nanocrystalline Ni0.5Zn0.5Fe2O4 ferrite powders0 aStructural magnetic and mossbauer spectral studies of nanocrysta aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcSEP a8999-90040 v5093 a

Nanocrystalline Ni0.5Zn0.5Fe2O4 powders, synthesized by a combustion method are investigated by X-ray diffraction, vibrating sample magnetometry and Mossbauer spectroscopic techniques. We adopt a strategy to systematically control the particle sizes between 4 and 45 nm simply by changing the elemental stoichiometric coefficient, Phi(e), of the combustion mixture. Curie temperature of the superparamagnetic particles of size 4 nm is higher than that of the bulk particles. Interestingly, bigger particles (45 nm) show a comparable room temperature saturation magnetization and exceptionally very high Curie temperature of 833 K, when compared to that of the bulk Ni0.5Zn0.5Fe2O4 material (563 K). (C) 2011 Elsevier B. V. All rights reserved.

10aChemical synthesis10aMagnetisation10aMossbauer spectroscopy10aNanostructured materials1 aVerma, Seema1 aJoy, Pattayil, Alias1 aKurian, Sajith uhttps://library.ncl.res.in/content/structural-magnetic-and-mossbauer-spectral-studies-nanocrystalline-ni05zn05fe2o4-ferrite-001774nas a2200205 4500008004100000022001400041245012000055210006900175260010600244300001400350490000800364520094100372653002001313653002401333653001801357653003001375100001701405700002501422856012101447 2012 eng d a0038-109800aEnhanced magnetic parameters in the morphotropic phase boundary region of nanocrystalline multiferroic Bi1-xLaxFeO30 aEnhanced magnetic parameters in the morphotropic phase boundary  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcAUG a1609-16120 v1523 a

Antiferromagnetic multiferroic BiFeO3 shows ferromagnetic characteristics by simultaneous substitution of Bi by La and decrease in the particle size to nanometer dimensions. Large changes in saturation and remnant magnetization, magnetic susceptibility at low and high fields, along with some anomalous changes in the magnetic transition temperature are observed in nanocrystalline Bi1-xLaxFeO3 system for 0.1 <= x <= 0.2. This compositional region corresponds to the morphotropic phase boundary (MPB) region separating the rhombohedral and orthorhombic phases, and the effect is similar to that observed in many ferroelectric systems. The present observation of enhanced ferromagnetic parameters in the MPB region of the nanocrystalline multiferroic La substituted BiFeO3 system, combined with the known ferroelectric characteristics, is suitable for future device applications. (C) 2012 Elsevier Ltd. All rights reserved.

10aBismuth ferrite10amagnetic properties10aMultiferroics10aNanocrystalline materials1 aThakuria, P.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhanced-magnetic-parameters-morphotropic-phase-boundary-region-nanocrystalline-001755nas a2200217 4500008004100000022001400041245013100055210006900186260007100255300001400326490000600340520092800346653001901274653002101293653002001314653001901334653001401353100002801367700002501395856011701420 2012 eng d a1944-824400aEnhancement in the magnetostriction of sintered cobalt ferrite by making self-composites from nanocrystalline and bulk powders0 aEnhancement in the magnetostriction of sintered cobalt ferrite b a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcDEC a6421-64250 v43 a

Sintered polycrystalline cobalt ferrite is a potential magnetostrictive smart material for applications as sensors and actuators. A novel concept of enhancing the magnetostrictive strain of sintered cobalt ferrite by making self-composites from nanosized and bulk powders with different particle sizes of the same material as components is reported. The self-composites give higher magnetostriction coefficient and strain derivative when compared to the sintered products obtained from the individual powders. The individual components give a maximum magnetostriction up to similar to 310 ppm, whereas up to similar to 370 ppm is obtained for a two-component system consisting of powders of two different sizes. On the other hand, a three-component self-composite made from starting powders of 3 nm, 40 nm and >1 mu m give very high magnetostriction of similar to 400 ppm at 800 kA/m, suitable for making devices.

10aCobalt ferrite10aMagnetostriction10aNanocrystalline10aself-composite10aSintering1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhancement-magnetostriction-sintered-cobalt-ferrite-making-self-composites-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

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.

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-001459nas a2200157 4500008004100000022001400041245012400055210006900179260012500248300001100373490000800384520073600392100002801128700002501156856012001181 2012 eng d a0003-695100aHigh magnetostriction and coupling coefficient for sintered cobalt ferrite derived from superparamagnetic nanoparticles0 aHigh magnetostriction and coupling coefficient for sintered coba aCIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USAbAMER INST PHYSICScAUG a0724050 v1013 a

High magnetostriction (lambda) and coupling coefficient (d lambda/dH) of 315 ppm and 1.97 x 10(-9) A(-1) m, respectively, are obtained at room temperature for sintered cobalt ferrite derived from nanocrystalline powders. Also, the powder was compacted at a low pressure of 8 MPa and sintered for a short duration of 10 min at 1450 degrees C. Magnetic annealing at 300 degrees C in a field of 0.5 T for 30 min further enhanced the magnetostriction coefficient to 345 ppm with a higher coupling coefficient 2.12 x 10(-9) A(-1)m. The magnetic field above which maximum magnetostriction is observed is reduced by almost half after magnetic annealing. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4745922]

1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/high-magnetostriction-and-coupling-coefficient-sintered-cobalt-ferrite-derived-002434nas a2200217 4500008004100000022001400041245010900055210006900164260007300233300001400306490000800320520160500328653001901933653002401952653002101976100001901997700002702016700002502043700001702068856013102085 2012 eng d a0304-885300aMagnetic and magnetoelastic properties of Zn-doped cobalt-ferrites-CoFe2-xZnxO4 (x=0, 0.1, 0.2, and 0.3)0 aMagnetic and magnetoelastic properties of Zndoped cobaltferrites aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUL a2286-22910 v3243 a

Cobalt-ferrite (CoFe2O4) based materials are suitable candidates for magnetomechanical sensor applications owing to a strong sensitivity of their magnetostriction to an applied magnetic field. Zn-doped cobalt-ferrites, with nominal compositions CoFe2-xZnxO4 (x=0-0.3), were synthesized by auto-combustion technique using Co-, Fe-, and Zn-nitrate as precursors. X-ray spectra analysis and Transmission electron microscopy studies revealed that the as-prepared powders were comprised of nano-crystalline (similar to 25-30 nm) cubic-spinel phase with irregularly-shaped grains morphology along with minor impurity phases. Calcination (800 degrees C for 3 h) of the precursor followed by sintering (1300 degrees C for 12 h) resulted in a single phase cubic-spinel structure with average grain size similar to 2-4 mu m, as revealed from scanning electron micrographs. The magnitude of coercive field decreases from similar to 540 Oe for x=0 to 105 Oe for x=0.30. Saturation magnetization initially increases and peaks to similar to 87 emu/g for x=0.2 and then decreases. The peak value of magnetostriction monotonically decreases with increasing Zn content in the range 0.0-0.3; however the piezomagnetic coefficient (d lambda/dH) reaches a maximum value of 105 x 10(-9) Oe-1 for x=0.1. The observed variation in piezomagnetic coefficient in the Zn substituted cobalt ferrite is related to the reduced anisotropy of the system. The Zn-doped cobalt-ferrite (x=0.1) having high strain derivative could be a potential material for stress sensor application. (C) 2012 Elsevier B.V. All rights reserved.

10aCobalt-ferrite10aMagnetic-properties10aMagnetostriction1 aSomaiah, Nalla1 aJayaraman, Tanjore, V.1 aJoy, Pattayil, Alias1 aDas, Dibakar uhttps://library.ncl.res.in/content/magnetic-and-magnetoelastic-properties-zn-doped-cobalt-ferrites-cofe2-xznxo4-x0-01-02-and-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

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.

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-001072nas a2200157 4500008004100000022001400041245008600055210006900141260011000210300001600320490000700336520040500343100002500748700002500773856011600798 2013 eng d a1463-907600aEvolution and magnetic characteristics of NiO-Ni(OH)(2) core-shell nanostructures0 aEvolution and magnetic characteristics of NiONiOH2 coreshell nan aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcOCT a20808-208120 v153 a

The evolution and magnetic behaviour of NiO-Ni(OH)(2) core-shell nanostructures with different thicknesses of the hydroxide shell have been studied. The nickel hydroxide shell is found to alter the magnetic characteristics of nickel oxide at low temperatures and explains the origin of the exchange bias effect due to the anti-ferromagnetic NiO core and a ferromagnetic nickel hydroxide shell.

1 aMahajan, Mangesh, B.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/evolution-and-magnetic-characteristics-nio-nioh2-core-shell-nanostructures-001798nas a2200217 4500008004100000022001400041245014400055210006900199260007300268300001400341490000700355520092600362653001901288653002901307653002101336653002001357653002001377100002801397700002501425856013001450 2013 eng d a1567-173900aHigh magnetostriction coefficient of Mn substituted cobalt ferrite sintered from nanocrystalline powders and after magnetic field annealing0 aHigh magnetostriction coefficient of Mn substituted cobalt ferri aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a1697-17010 v133 a

Magnetostriction characteristics of Mn substituted cobalt ferrite, CoFe2-xMnxO4 (0 <= x <= 0.3), sintered from nanocrystalline powders of average particle size of similar to 4 nm have been studied. Larger value of magnetostriction at lower magnetic field is achieved after substitution of Mn for Fe. The maximum value of magnetostriction coefficient is not much affected and the slope of the magnetostriction is increased with increasing Mn content. Higher maximum value of magnetostriction coefficient (lambda) of 234 ppm comparable to that of the unsubstituted composition with larger strain derivative (d lambda/dH) is obtained for x = 0.2 in CoFe2-xMnxO4. The magnetostriction coefficient is increased to 262 ppm with further enhancement in the strain derivative after annealing the sintered compact at 300 degrees C in a magnetic field of 400 kA/m for 30 min. (C) 2013 Elsevier B.V. All rights reserved.

10aCobalt ferrite10aMagnetic field annealing10aMagnetostriction10aMn substitution10aNanocrystalline1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/high-magnetostriction-coefficient-mn-substituted-cobalt-ferrite-sintered-nanocrystalline-001678nas a2200229 4500008004100000022001400041245012700055210006900182260007300251300001100324490000800335520080900343653001901152653002401171653002101195653001901216653002001235653001801255100002801273700002501301856012201326 2013 eng d a0304-885300aInfluence of initial particle size on the magnetostriction of sintered cobalt ferrite derived from nanocrystalline powders0 aInfluence of initial particle size on the magnetostriction of si aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcNOV a96-1020 v3463 a

The role of initial particle size on the magnetostriction coefficient of sintered cobalt ferrite derived from nanocrystalline powders is studied. Nanoparticles of cobalt ferrite with different sizes in the range 3-80 nm are synthesized by an autocombustion method using metal nitrates and glycine. It has been observed that the initial particle size of the starting powders has a strong influence on the magnetostrictive behavior of sintered cobalt ferrite. Highest magnetostrictive strain and strain derivative are obtained for sintered ferrite derived from nanoparticles of size < 5 nm. The results show that higher magnetostriction coefficient for sintered cobalt ferrite can be achieved by compacting nanocrystalline particles of very small size. (C) 2013 Elsevier B.V. All rights reserved.

10aCobalt ferrite10amagnetic properties10aMagnetostriction10aMicrostructure10aNanocrystalline10aParticle size1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/influence-initial-particle-size-magnetostriction-sintered-cobalt-ferrite-derived-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

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.

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-001313nas a2200157 4500008004100000022001400041245006700055210006700122260007300189300001000262490000800272520073600280100001601016700002501032856009801057 2014 eng d a0009-261400aFerromagnetism at room temperature in activated graphene oxide0 aFerromagnetism at room temperature in activated graphene oxide aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJUN a89-920 v6053 a

High room temperature ferromagnetic moment with high Curie temperature (>700 K) for graphene oxide (GO) is obtained by a simple chemical activation using phosphoric acid followed by heat treatment at 800 degrees C. The field and temperature variations of the magnetization data indicate ferromagnetic, paramagnetic and diamagnetic contributions in the acid/heat treated sample. IR spectroscopic studies suggest hydrogenation (reduction) of GO after the acid and heat treatments. The results point to the role of defects, extent of hydrogenation, changes in the bonding characteristics and the nature of the functional groups in determining the different magnetic contributions. (C) 2014 Elsevier B.V. All rights reserved.

1 aRaj, Govind1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/ferromagnetism-room-temperature-activated-graphene-oxide-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

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.

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-2-12-001776nas a2200193 4500008004100000022001400041245011300055210006900168260007300237300001200310490000800322520100800330653001901338653002101357653002401378100002801402700002501430856012701455 2014 eng d a0304-885300aHigh magnetostriction parameters for low-temperature sintered cobalt ferrite obtained by two-stage sintering0 aHigh magnetostriction parameters for lowtemperature sintered cob aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcDEC a121-1290 v3713 a

From the studies on the magnetostriction characteristics of two-stage sintered polycrystalline CoFe2O4 made from nanocrystalline powders, it is found that two-stage sintering at low temperatures is very effective for enhancing the density and for attaining higher magnetostriction coefficient. Magnetostriction coefficient and strain derivative are further enhanced by magnetic field annealing and relatively larger enhancement in the magnetostriction parameters is obtained for the samples sintered at lower temperatures, after magnetic annealing, despite the fact that samples sintered at higher temperatures show larger magnetostriction coefficients before annealing. A high magnetostriction coefficient of similar to 380 ppm is obtained after field annealing for the sample sintered at 1100 degrees C, below a magnetic field of 400 kA/m, which is the highest value so far reported at low magnetic fields for sintered polycrystalline cobalt ferrite. (C) 2014 Elsevier B.V. All rights reserved.

10aCobalt ferrite10aMagnetostriction10aTwo-stage sintering1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/high-magnetostriction-parameters-low-temperature-sintered-cobalt-ferrite-obtained-two-001420nas a2200205 4500008004100000022001400041245008100055210006900136260010600205300001000311490000800321520065800329653002100987653002201008653001901030653002401049100001601073700002501089856010001114 2014 eng d a0038-109800aMagnetism in disordered carbon as a function of the extent of graphitization0 aMagnetism in disordered carbon as a function of the extent of gr aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJAN a89-940 v1773 a

Magnetic properties of disordered carbon have been investigated as a function of the extent of graphitization. It is found that the magnetization of the disordered carbon decreases with increasing degree of graphitization. Treatment with acid modifies the magnetic characteristics considerably and the original magnetic characteristics are retained upon further heat treatment. The results show that the intrinsic magnetic behavior of the disordered carbon depends on the microstructure and that the edge states play a critical role in deciding the magnetic interactions in the amorphous carbon system. (C) 2013 Elsevier Ltd. All rights reserved.

10aAmorphous carbon10adisordered carbon10aGraphitization10amagnetic properties1 aRaj, Govind1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/magnetism-disordered-carbon-function-extent-graphitization-002009nas a2200217 4500008004100000022001400041245014500055210006900200260009900269300001200368490000700380520113300387653001901520653002101539653001901560653002001579653001401599100002801613700002501641856012501666 2014 eng d a0955-221900aStudies on the effect of sintering conditions on the magnetostriction characteristics of cobalt ferrite derived from nanocrystalline powders0 aStudies on the effect of sintering conditions on the magnetostri aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcMAR a677-6860 v343 a

The effect of sintering conditions on the magnetostriction characteristics of sintered cobalt ferrite derived from nanocrystalline powders is studied. It is observed that the magnetostriction coefficient as well as the slope of the magnetostriction as a function of field depends on the microstructure of the sintered product. There is a direct correlation between the magnetostriction characteristics and density as well as porosity of the sintered products. Intragranular pores are found to be strongly influencing the magnetostriction characteristics. Similarly, correlation is found between the magnetostriction parameters and the Curie temperature, indicating the role of cation distribution which affects the magnetic anisotropy. Sintering the compacts made from nanocrystalline powders at 1450 degrees C for a very short duration is found to give high values of magnetostriction coefficient. However, higher values of magnetostriction at low magnetic fields are obtained for samples sintered at lower temperatures for longer duration and having relatively lower density. (C) 2013 Elsevier Ltd. All rights reserved.

10aCobalt ferrite10aMagnetostriction10aMicrostructure10aNanocrystalline10aSintering1 aMohaideen, Kamal, Khaja1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/studies-effect-sintering-conditions-magnetostriction-characteristics-cobalt-ferrite-001424nas a2200229 4500008004100000022001400041245008600055210006900141260007700210300001200287490000700299520055300306653002400859653003000883653003800913653002500951100002600976700002001002700002501022700002801047856011901075 2014 eng d a0934-086600aSynthesis and reactivity of magnetically diverse Au@ Ni core-shell nanostructures0 aSynthesis and reactivity of magnetically diverse Au Ni coreshell aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcFEB a236-2440 v313 a

Core-shell bimetallic Au@Ni nanoparticles, with gold cores and thin nickel shells with overall size less than 10 nm, are synthesized and stabilized in pure cubic (fcc) and hexagonal (hcp) phase. Due to their unique crystal, electronic, and geometric structure, they show interesting magnetic and chemical properties. The Au@Ni-fcc is magnetic, whereas Au@Ni-hcp is non-magnetic. Both the bimetallic nanostructures are stable to surface oxidation until 150 degrees C and show excellent catalytic activity for p-nitrophenol reduction reaction.

10aAu-Ni nanoparticles10abimetallic nanostructures10amagnetic core-shell nanoparticles10aoxidation resistance1 aBharathan, Vysakh, A.1 aRaj, Govind, K.1 aJoy, Pattayil, Alias1 aVinod, Chathakudath, P. uhttps://library.ncl.res.in/content/synthesis-and-reactivity-magnetically-diverse-au-ni-core-shell-nanostructures-001521nas a2200145 4500008004100000245013400041210006900175260000800244300001600252490000600268520092100274100002801195700002501223856012701248 2015 eng d00aCitrate modified beta-cyclodextrin functionalised magnetite nanoparticles: a biocompatible platform for hydrophobic drug delivery0 aCitrate modified betacyclodextrin functionalised magnetite nanop cFEB a22117-221250 v53 a

Water-dispersible magnetite nanoparticles functionalized with citric acid (CIT) modified beta-cyclodextrin (CD) are prepared and curcumin (CUR) is loaded inside the cavity of CD. The CUR loading capacity of CD-CIT functionalized magnetite nanoparticles is found to be much larger than that of CD alone as well as the CD-CIT conjugate. The release profile of curcumin is found to follow zero order kinetics at the physiological pH, and thus, can release CUR at a constant rate, after the initial burst release. Relaxivity studies using NMR showed that the functionalized nanoparticles are suitable for contrast enhancement in MRI. Thus, the water-dispersible, CIT modified beta-CD functionalized magnetite nanofluid is an efficient carrier for water insoluble curcumin, and can be used for magnetic drug targeting/delivery as well as for contrast enhancement in MRI due to the superparamagnetic magnetite core.

1 aJayaprabha, Kunnoth, N.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/citrate-modified-beta-cyclodextrin-functionalised-magnetite-nanoparticles-biocompatible00694nas a2200169 4500008004100000022001400041245009600055210006900151260005700220300001200277490000600289100002400295700002400319700003000343700002500373856012600398 2015 eng d a1868-252900aCo3O4 nanorods-efficient non-noble metal electrocatalyst for oxygen evolution at neutral pH0 aCo3O4 nanorodsefficient nonnoble metal electrocatalyst for oxyge a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUL a331-3400 v61 aRamsundar, Rani, M.1 aDebgupta, Joyashish1 aPillai, Vijayamohanan, K.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/co3o4-nanorods-efficient-non-noble-metal-electrocatalyst-oxygen-evolution-neutral-ph-000629nas a2200145 4500008004100000245013700041210006900178260000800247300002100255490000600276100001500282700003200297700002500329856012900354 2015 eng d00aCorrelations between structure, microstructure, density and dielectric properties of the lead-free ferroelectrics Bi0.5(Na,K)0.5TiO30 aCorrelations between structure microstructure density and dielec cNOV a1550028 Page 1-60 v51 aAnjali, K.1 aAjithkumar, Thalasseril, G.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/correlations-between-structure-microstructure-density-and-dielectric-properties-lead-free01427nas a2200157 4500008004100000022001400041245015000055210006900205260011000274300001600384490000700400520068000407100002601087700002501113856013101138 2015 eng d a1463-907600aCross over from 3D variable range hopping to the 2D weak localization conduction mechanism in disordered carbon with the extent of graphitization0 aCross over from 3D variable range hopping to the 2D weak localiz aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY a16178-161850 v173 a

The changes in the electrical transport properties and mechanism of conduction in disordered carbon, with the extent of graphitization, are studied and discussed. With heat treatment induced graphitic ordering, the electrical properties are considerably modified, inducing a crossover from strong localization to weak localization behavior. Accordingly, the conduction mechanism is modified from the 3-dimensional variable range hopping (3D VRH) model to the 2-dimensional weak localization (2D WL) model. Results show that carrier-carrier and carrier-phonon interactions play major roles in developing the weak localization behavior with the extent of graphitization.

1 aRaj, Kovummal, Govind1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/cross-over-3d-variable-range-hopping-2d-weak-localization-conduction-mechanism-disordered-001979nas a2200301 4500008004100000022001400041245010500055210006900160260007300229300001000302490000800312520097700320653001001297653001801307653001301325653002501338653001901363653000801382653000801390100001801398700002501416700001801441700002501459700002301484700002701507700002101534856012201555 2015 eng d a0921-510700aPreparation and characterization of flexible ferromagnetic nanocomposites for microwave applications0 aPreparation and characterization of flexible ferromagnetic nanoc aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a40-490 v2003 a

Magnetic Fe3O4 nanoparticles (similar to 20 nm) were synthesized using the chemical co-precipitation method with a view of developing flexible and easily processable ferromagnetic materials with high mouldability to be used as microwave absorbers. The nanoparticles prepared were incorporated into natural rubber through latex stage processing. This novel processing method gives better dispersion of particles in the rubber matrix. The composites were characterized using XRD, SEM, vibrating sample magnetometer, dynamic mechanical analyzer, cavity perturbation, thermogravimetry (TGA), and Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS). A notable improvement in the mechanical properties of composites was observed upon adding Fe3O4 particles. Magnetic and microwave characteristics of the composites indicate the formation of a flexible ferromagnetic material with good microwave absorption characteristics. (C) 2015 Published by Elsevier B.V.

10aFe3O410aFerromagnetic10aFTIR-PAS10aMicrowave absorption10aNatural rubber10aSEM10aXRD1 aThomas, Teena1 aKanoth, Bipinbal, P.1 aNijas, C., M.1 aJoy, Pattayil, Alias1 aJoseph, Joseph, M.1 aKuthirummal, Narayanan1 aThachil, Eby, T. uhttps://library.ncl.res.in/content/preparation-and-characterization-flexible-ferromagnetic-nanocomposites-microwave-001538nas a2200265 4500008004100000022001400041245011300055210006900168260005700237300001400294490000700308520058700315653001800902653002600920653002500946653002200971100002100993700002201014700001901036700001901055700002101074700002501095700002701120856012501147 2015 eng d a0361-523500aTuning magnetic behavior of nanoscale cobalt sulfide and its nanocomposite with an engineering thermoplastic0 aTuning magnetic behavior of nanoscale cobalt sulfide and its nan a233 SPRING ST, NEW YORK, NY 10013 USAbSPRINGERcJUL a2308-23110 v443 a

Nanocomposites containing magnetic nanoparticles embedded in a polymer matrix with good thermal stability (up to 200A degrees C) are technologically important. We report an environmentally benign solid-solid approach for synthesis of cobalt sulfide and its nanocomposite using a thermally stable matrix of polyphenylene sulfide. Physicochemical characterizations reveal the formation of nanoclusters of the hexagonal phase CoS. Even though bulk CoS is nonmagnetic, magnetization studies exhibit anomalous magnetic behavior for phase-pure nanoscale CoS and its nanocomposites.

10aNanocomposite10apolyphenylene sulfide10aSolid-solid reaction10asuperparamagnetic1 aRumale, Narendra1 aArbuj, Sudhir, S.1 aUmarji, Govind1 aShinde, Manish1 aMulik, Uttam, P.1 aJoy, Pattayil, Alias1 aAmalnerkar, Dinesh, P. uhttps://library.ncl.res.in/content/tuning-magnetic-behavior-nanoscale-cobalt-sulfide-and-its-nanocomposite-engineering-000576nas a2200145 4500008004100000245009900041210006900140260000800209300001200217490000600229100001500235700002800250700002500278856012700303 2015 eng d00aWater-dispersible ascorbic-acid-coated magnetite nanoparticles for contrast enhancement in MRI0 aWaterdispersible ascorbicacidcoated magnetite nanoparticles for  cJAN a435-4410 v51 aSreeja, V.1 aJayaprabha, Kunnoth, N.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/water-dispersible-ascorbic-acid-coated-magnetite-nanoparticles-contrast-enhancement-mri01760nas a2200157 4500008004100000022001400041245016800055210006900223260011000292300001600402490000700418520099400425100002701419700002501446856013101471 2016 eng d a1463-907600aEnhancing the strain sensitivity of CoFe2O4 at low magnetic fields without affecting the magnetostriction coefficient by substitution of small amounts of Mg for Fe0 aEnhancing the strain sensitivity of CoFe2O4 at low magnetic fiel aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcAPR a10516-105270 v183 a

Attaining high magnetostrictive strain sensitivity (d lambda/dH) with high magnetostriction strain (lambda) is desirable for sintered polycrystalline cobalt ferrite for various applications. It is shown that substitution of a small amount of Fe3+ by Mg2+ in CoMgxFe2-xO4 (x < 0.1) gives a comparable maximum magnetostriction coefficient to that of the unsubstituted counterpart, with large improvement in the strain sensitivity at relatively low magnetic fields. A large increase in the magnetostriction coefficient is obtained at low magnetic fields for the substituted compositions. The magnetostriction parameters are further enhanced by magnetic field annealing of the sintered products. The results are analyzed based on powder XRD, Raman spectroscopy, XPS and magnetic measurements and based on the results from these studies, the changes in the magnetostriction parameters are correlated with the changes in the cation distribution, magnetic anisotropy and microstructure.

1 aAnantharamaiah, P., N.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/enhancing-strain-sensitivity-cofe2o4-low-magnetic-fields-without-affecting-magnetostriction02581nas a2200157 4500008004100000022001400041245012300055210006900178260007100247300001600318490000800334520191100342100002102253700002502274856012402299 2016 eng d a1932-744700aRole of primary and secondary surfactant layers on the thermal conductivity of lauric acid coated magnetite nanofluids0 aRole of primary and secondary surfactant layers on the thermal c a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN a11640-116510 v1203 a

Lauric (dodecanoic) acid coated magnetite nanoparticles with different amounts of primary and secondary surfactant layers on the surface of the nanoparticles have been synthesized. Two sets of the surfactant coated nanoparticles are prepared; one with a comparable amount of primary surfactant and the other with a comparable amount of secondary surfactant. Nanofluids are prepared by dispersing the surfactant coated nanoparticles in toluene. Stability of the nanofluids is found to decrease with increasing amount of secondary surfactant on the surface of the nanoparticles, due to the increased hydrophilic nature of the particles in the nonpolar solvent. Thermal conductivity and viscosity of the nanofluids are found to increase with increasing amount of the secondary surfactant layer on the surface of the nanoparticles. The enhanced thermal conductivity for fluids with particles having a larger amount of secondary surfactant is ascribed to the lower dispersibility of the particles in toluene due to the exposure of the acid group of the surfactant to the hydrophobic solvent, leading to aggregation of the particles. Only a small increase in the thermal conductivity is observed for fluids with a larger amount of primary surfactant on the surface of the nanoparticles due to the increased dispersibility owing to the large number of hydrophobic tail groups of the surfactant. A larger enhancement in the thermal conductivity is observed in the presence of a small magnetic field for the fluids containing particles with a lower amount of the secondary surfactant. The overall results suggest that the thermal conductivity of the nanofluids depend on the amount and nature of the primary and secondary surfactants on the dispersed particles which in turn determine the interaction between the base fluid and the surfactant and therefore the dispersibility and stability of the nanofluids.

1 aLenin, Ramanujam1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/role-primary-and-secondary-surfactant-layers-thermal-conductivity-lauric-acid-coated01230nas a2200145 4500008004100000245006800041210006800109260000800177300001200185490000800197520073100205100002300936700002500959856010000984 2017 eng d00aMagnetoelastic properties of terbium substituted cobalt ferrite0 aMagnetoelastic properties of terbium substituted cobalt ferrite cOCT a465-4690 v6853 aThe magnetic properties of terbium substituted cobalt ferrites CoFe(2-x)TbxO(4) (x = 0, 0.05, 0.1, 0.15 and 0.2) prepared by conventional solid state method are studied. The coercivity showed marked increase up to x = 0.1 and saturation magnetization decreased with increasing terbium content. Magnetostriction measurements did not show much decrease in the maximum value of strain but significant increase in the slope of magnetostriction was observed for x = 0.15 with moderate magnetostriction of around 144 ppm. The observed magnetic and magnetostrictive properties can be explained on the basis of structural and microstructural changes arising because of terbium substitution. (C) 2017 Elsevier B.V. All rights reserved.1 aBhame, Shekhar, D.1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/magnetoelastic-properties-terbium-substituted-cobalt-ferrite02798nas a2200325 4500008004100000022001400041245009300055210006900148260000800217490000800225520177900233653002002012653001602032653003402048653002402082653001802106653001802124653002302142653000902165653001402174653001502188653001502203653002502218653003002243653002402273653001402297100002102311700002502332856011502357 2017 eng d a0927-775700aRole of base fluid on the thermal conductivity of oleic acid coated magnetite nanofluids0 aRole of base fluid on the thermal conductivity of oleic acid coa cSEP0 v5293 a

Thermal conductivity enhancement of nanofluids of oleic acid coated magnetite nanoparticles dispersed in four different base fluids (toluene, xylene, mesitylene, kerosene) is studied to understand the role of the solvent (base fluid). From the correlation of the thermophysical properties of the base fluid with the thermal conductivity of the corresponding nanofluid, it is found that the nanofluid with the base fluid of lower intrinsic thermal conductivity and dielectric constant shows relatively larger enhancement in the thermal conductivity. A linear increase in the thermal conductivity with increasing viscosity is observed for all four nanofluids studied. The concentration dependent thermal conductivity studies showed enhancement only above a particular concentration, within the sensitivity of the measurement, and this critical concentration is different for the different nanofluids. The nanofluid with kerosene showed the lowest critical concentration for thermal conductivity enhancement compared to the other nanofluids. The difference between the experimental thermal conductivity and the calculated value using the Maxwell model is found to depend on the critical concentration. By assuming the critical concentration as the zero concentration, it is found that all the studied nanofluids almost follow the Maxwell model of thermal conductivity. Thus, for the dispersions of the same oleic acid coated magnetite nanoparticles, the base fluid affects the critical concentration for thermal conductivity enhancement, probably due to the interfacial effects arising from the surfactant-solvent interactions.

10aBrownian-Motion10aEnhancement10aHeat-transfer Characteristics10aMagnetic nanofluids10aMaxwell model10aNanoparticles10aParticle Migration10aSize10astability10aSuspension10aTemprature10aThermal conductivity10aThermophysical properties10atransport mechanism10aviscosity1 aLenin, Ramanujam1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/role-base-fluid-thermal-conductivity-oleic-acid-coated-magnetite-nanofluids01424nas a2200145 4500008004100000245010000041210006900141260000800210300001400218490000800232520086600240100002601106700002501132856012101157 2017 eng d00a Role of localized graphitization on the electrical and magnetic properties of activated carbon0 aRole of localized graphitization on the electrical and magnetic  cNOV a5151-51610 v1003 aThe correlation between the magnetic and electrical properties of activated carbon with its microstructure is studied. The changes in the microstructure of activated carbon, after activation at three different temperatures (800 degrees C, 900 degrees C, 1000 degrees C) using different amounts of the activating agent, KOH (KOH/C ratio of 1: 1, 2: 1, 3: 1 and 4: 1), are studied using X-ray diffraction and Raman spectroscopy. The results showed the formation of localized nanographitic domains, along with the changes in the surface area and porosity of the activated carbon. The changes in the microstructure are found to be directly correlated with the magnetic properties and electrical conductivity. The interplay between ordering and disordering parameters in the activated carbon is found to determine the electrical conductivity and magnetic properties.1 aRaj, Kovummal, Govind1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/role-localized-graphitization-electrical-and-magnetic-properties-activated-carbon02540nas a2200253 4500008004100000022001400041245013000055210006900185260000800254490000800262520161400270653001101884653001301895653001601908653001101924653001101935653001101946653002301957653010301980653003002083100002102113700002502134856012702159 2017 eng d a0021-979700aStudies on the role of unsaturation in the fatty acid surfactant molecule on the thermal conductivity of magnetite nanofluids0 aStudies on the role of unsaturation in the fatty acid surfactant cNOV0 v5063 a

To study the role of unsaturation in the surfactant molecule on the thermal conductivity of magnetite nanofluids, four different fatty acid (stearic, oleic, linoleic, and linolenic acids with different degree of unsaturation) coated magnetite nanoparticles of comparable size are prepared and dispersed in toluene. It is found that the nanofluid with the saturated fatty acid coated nanoparticles show larger viscosity than the fluid with the unsaturated fatty acid coated particles at all concentrations. Thermal conductivity studies show enhancement only above a critical concentration for all fluids. The critical concentration for thermal conductivity enhancement varies with the surfactant, possibly due to the difference in the degree of aggregation of the nanoparticles in the fluid, because of the difference in the conformation of the surfactant molecules on the nanoparticle's surface. The experimental thermal conductivity follows the Maxwell model at higher concentrations. From the overall studies, it is observed that the thermal conductivity of the fluids with aggregated or assembled nanoparticles shows slightly larger enhancement than that of the fluids with isolated particles. However, in the presence of a magnetic field, the fluids with isolated nanoparticles showed relatively larger enhancement, possibly due to the easy response of the isolated magnetite nanoparticles to the applied field. (C) 2017 Elsevier Inc. All rights reserved.

10aChains10aDynamics10aEnhancement10aFields10aFluids10aForces10agold nanoparticles10aMagnetic fluid; Nanofluid; Surfactant; Unsaturation; Conformation; Thermal conductivity; Viscosity10aSelf-assembled Monolayers1 aLenin, Ramanujam1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/studies-role-unsaturation-fatty-acid-surfactant-molecule-thermal-conductivity-magnetite01681nas a2200169 4500008004100000022001400041245008800055210006900143260000800212300001600220490000700236520106300243100002701306700003801333700002501371856011501396 2018 eng d a1463-907600a Spin state engineered ZnxCo3-xO4 as an efficient oxygen evolution electrocatalyst 0 aSpin state engineered ZnxCo3xO4 as an efficient oxygen evolution cDEC a29452-294610 v203 aOxygen evolution is the key step in the oxidation of water in electrolyzers and photoelectrochemical cells for the production of hydrogen. Developing a non-precious metal oxide catalyst with good electrocatalytic activity for the oxygen evolution reaction (OER) is very challenging. In this work, nanostructured ZnxCo3-xO4 has been shown as an efficient catalyst with a low overpotential for the OER in 0.1 M KOH solution. Substitution of Co2+ in the spinel oxide Co3O4 with Zn2+ creates a higher number of high-spin Co3+, which is found to be directly correlated with the OER activity of ZnxCo3-xO4. Zn0.8Co2.2O4 (x = 0.8) with the optimum amount of Co2+/Co3+ and high-spin Co3+ content showed a very low overpotential of approximate to 250 mV, at 10 mA cm(-2), with a turnover frequency of approximate to 3 x 10(-3) s(-1) for the OER. The high Faradaic efficiency along with the stability of Zn0.8Co2.2O4 and electrocatalytic activity comparable with that of precious metal oxides indicate that this composition is a promising catalyst for water oxidation.1 aRamsundar, Rani, Mohan1 aPillai, Vijayamohanan, Kunjukrish1 aJoy, Pattayil, Alias uhttps://library.ncl.res.in/content/spin-state-engineered-znxco3-xo4-efficient-oxygen-evolution-electrocatalyst02310nas a2200253 4500008004100000022001400041245013000055210006900185260000900254300001400263490000600277520143200283653001901715653001601734653001601750653002401766653001701790100002901807700001801836700001701854700002501871700003101896856012901927 2019 eng d a2365-654900aSize-controlled cobalt ferrite nanocrystals: magnetically separable reusable nanocatalysts for selective oxidation of styrene0 aSizecontrolled cobalt ferrite nanocrystals magnetically separabl cJUN  a6524-65310 v43 a

Superparamagnetic cobalt ferrite (CFO) nanocrystals (NCs) with sizes similar to 6 nm and similar to 4 nm were synthesized using a facile solvothermal method using fatty acids, lauric acid and stearic acid, as the capping agents. The synthesized nanocrystals were well characterized by XRD, FT-IR, XPS, SEM and TEM. The formation mechanism was explored and it was shown that the fatty acid was actually chemisorbed as a carboxylate onto the surface of CFO NCs. The experimental results specify that the size and size distribution of the CFO NCs were highly dependent on the length of fatty acid hydrophobic chain. Corresponding changes of the magnetic properties were investigated by measuring magnetization as a function of field and temperature, which suggest that the CFO NCs were superparamagnetic in nature. The catalytic properties for the oxidation of styrene in organic medium were examined by using the synthesized CFO NCs with sizes similar to 6 nm and similar to 4 nm. The synthesized CFO NCs, well dispersible in organic media, were demonstrated to be highly catalytically active, reached 100% conversion of styrene in 12 h with similar to 77% and similar to 82% selectivity for styrene oxide respectively. The magnetic CFO nanocatalysts were easily separated and recovered from the reaction medium by an external magnet, and reused for several cycles without losing catalytic selectivity for styrene oxide.

10aCobalt ferrite10aepoxidation10aFatty acids10amagnetic properties10ananocrystals1 aJeyavani, Vijayakrishnan1 aPawar, Sayali1 aDadwal, Arun1 aJoy, Pattayil, Alias1 aMukherjee, Shatabdi, Porel uhttps://library.ncl.res.in/content/size-controlled-cobalt-ferrite-nanocrystals-magnetically-separable-reusable-nanocatalysts02033nas a2200229 4500008004100000022001400041245007100055210006900126260000900195300001100204490000800215520131000223653002201533653003601555653001401591653001601605653002501621100002101646700002501667700001801692856009301710 2021 eng d a0167-732200aReview of the recent progress on thermal conductivity of nanofluid0 aReview of the recent progress on thermal conductivity of nanoflu cSEP  a1169290 v3383 aThermal properties of nanofluids are very well investigated by the global research community for their various applications. The dispersion and stability of the nanoparticles in the base fluid are the essential requirements for the efficient utilization of nanofluids in many applications. The interfacial layer plays a crucial role in the dispersion, stability, and heat transfer properties of the nanofluid. The heat transfer property of the nanofluids is mainly influenced by the heat transfer properties at the particle-fluid interface. The thickness and thermal conductivity of the interfacial layer are the crucial factors that decide the heat transfer at the interface, and the difficulties in the determination of these factors limits the progress of the research. In this review article, the experimental studies on the thickness and thermal conductivity of the interfacial layer are reviewed briefly. The effect of interfacial the layer on the nanoscale mechanisms and thermophysical properties of nanofluids are reviewed. The effect of various tunable parameters on the heat transfer properties of the interfacial layer is also reviewed. This review will be beneficial for fine-tuning nanofluid's thermal properties and their commercial applications. (C) 2021 Elsevier B.V. All rights reserved.10aInterfacial layer10aInterfacial thermal conductance10aNanofluid10aSurfactants10aThermal conductivity1 aLenin, Ramanujam1 aJoy, Pattayil, Alias1 aBera, Chandan uhttps://library.ncl.res.in/content/review-recent-progress-thermal-conductivity-nanofluid01983nas a2200241 4500008004100000022001400041245012100055210006900176260000900245300000800254490000700262520111400269653001301383653002301396653002801419653003001447653002701477100002901504700002001533700002501553700003101578856013201609 2022 eng d a0250-470700aMgB2/NaNO2-PVA free-standing polymer composite film as a green firework: a step towards environmental sustainability0 aMgB2NaNO2PVA freestanding polymer composite film as a green fire cSEP  a1750 v453 a

We have demonstrated a simple fabrication methodology of free-standing polymer composite film firework that sparkles, provides colour display and moderate sound, yet is less polluting. The polymer composite film fireworks are composed of magnesium boride (MgB2), sodium nitrite (NaNO2) and poly(vinyl alcohol) (PVA). This study also suggested that a flammable, explosive powder composition can be made of two very common inorganic precursors, mainly NaNO2 and MgB2 . This is the first report demonstrating composite film fireworks with new flammable composition using metal boride as a primary precursor, which can also be used in conventional fireworks fabrication, replacing the traditional fuel, mainly gunpowder. The film fireworks were free from charcoal, sulphur, metal powder and paper. Therefore, they substantially lower the odour and COx, NOx, emissions and minimize the substantial trash generated when burned. Most importantly, film firework's minimum ignition temperature and exothermic decomposition temperature are much higher than the ambient temperature; hence are safe to handle.

10aFirework10afree-standing film10amagnesium boride (MgB2)10apoly(vinyl alcohol) (PVA)10asodium nitrite (NaNO2)1 aJeyavani, Vijayakrishnan1 aKumar, Rajendra1 aJoy, Pattayil, Alias1 aMukherjee, Shatabdi, Porel uhttps://library.ncl.res.in/content/mgb2nano2-pva-free-standing-polymer-composite-film-green-firework-step-towards-environmental