Anantharaman, M R; Asha, Mary John; Mathew, George; Swapna, Nair S; Joy, P A(Elsevier, October 10, 2005)
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Abstract:
Nanoparticles of nickel ferrite have been synthesized by the sol–gel method and the effect of grain size on 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 15nm and then decreased as the grain size was increased further.
Description:
Journal of Magnetism and Magnetic Materials 302 (2006) 190–195
Anantharaman, M R; Muhammad, Abdul Jamal E; Sakthi Kumar, D(Springer, December 22, 2008)
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Abstract:
Zinc aluminate nanoparticles with average particle size of 40 nm were synthesized using a sol–gel combustion
method. X-ray diffractometry result was analysed by Rietveld refinement method to establish the phase
purity of the material. Different stages of phase formation of the material during the synthesis were investigated
using differential scanning calorimetry and differential thermogravimetric analysis. Particle size was determined
with transmission electron microscopy and the optical bandgap of the nanoparticles was determined by absorption
spectroscopy in the ultraviolet-visible range. Dielectric permittivity and a.c. conductivity of the material were
measured for frequencies from 100 kHz to 8 MHz in the temperature range of 30–120◦C. The presence of Maxwell–
Wagner type interfacial polarization was found to exist in the material and hopping of electron by means of quantum
mechanical tunneling is attributed as the reason for the observed a.c. conductivity
Description:
Bull. Mater. Sci., Vol. 34, No. 2, April 2011, pp. 251–259
Sreekumar, K; Rajesh Krishnan, G(Taylor & Francis, February 22, 2010)
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Abstract:
Poly(amidoamine) dendrimers were synthesized on cross-linked aminomethyl polystyrene. Palladium
complexes of supported dendrimers prepared by ligand exchange method were reduced to dendrimernanoparticle
conjugates supported on polystyrene resin. The supported nanoparticles were used as
heterogeneous catalysts for the Suzuki coupling between aryl boronic acids and aryl halides. Various factors
affecting the catalysts performance were studied. Higher generation dendrimers gave well-defined
nanoparticles without agglomeration and these particles showed good catalytic performance