02098nas a2200265   4500008004100000022001400041245009500055210006900150260006900219300001400288490000800302520117200310653002201482653002601504653001801530653002901548653000801577100002201585700002201607700001801629700002201647700002101669700001601690856012601706       2011                        eng d  a0925-838800aMagnetic properties of thermal plasma synthesized nanocrystalline nickel ferrite (NiFe2O4)0 aMagnetic properties of thermal plasma synthesized nanocrystallin  aPO BOX 564, 1001 LAUSANNE, SWITZERLANDbELSEVIER SCIENCE SAcMAR  a4404-44130 v5093 a<p>A rapid synthesis method is reported for magnetic nanoparticles of nickel ferrite involving thermal plasma assisted vapor phase condensation process. The as-synthesized samples were characterized by X-ray Diffraction, Transmission Electron Microscopy, Vibrating Sample Magnetometer and X-ray Photoelectron Spectroscopy techniques. The average particle size was determined from the TEM micrographs and found to be around 30 nm. The effects of reactor parameters on the magnetic and structural properties have been evaluated, to find the optimized parameters so as to achieve the highest values of saturation magnetization and coercivity. Reasonably high saturation magnetization (48 emu/g) has been assigned to the high degree of crystallinity, achieved on account of high temperature during the growth, and the cation redistribution. The high value of coercivity (1150e) is explained on the basis of possible lattice defects arising from the cation redistribution. Detailed analysis of cation distribution using the XRD line intensity data leads to the conclusion that these samples are iron deficit and nickel rich. (C) 2011 Elsevier B.V. All rights reserved.</p>10acrystal structure10aMagnetic measurements10aMagnetization10aNanostructured materials10aTEM1 aNawale, Ashok, B.1 aKanhe, Nilesh, S.1 aPatil, K., R.1 aBhoraskar, S., V.1 aMathe, Vikas, L.1 aDas, A., K.  uhttp://library.ncl.res.in/content/magnetic-properties-thermal-plasma-synthesized-nanocrystalline-nickel-ferrite-nife2o4-002431nas a2200265   4500008004100000022001400041245008900055210006900144260007300213300001000286490000800296520147600304653002301780653004301803653001201846653003701858100002201895700002201917700002301939700002601962700002201988700001902010700002102029856011502050       2012                        eng d  a0022-024800aUnderstanding the growth of micro and nano-crystalline AlN by thermal plasma process0 aUnderstanding the growth of micro and nanocrystalline AlN by the  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJAN  a36-450 v3393 a<p>We report the studies related to the growth of crystalline AlN in a DC thermal plasma reactor, operated by a transferred arc plasma torch. The reactor is capable of producing the nanoparticles of Al and AlN depending on the composition of the reacting gas. Al and AlN micro crystals are formed at the anode placed on the graphite and nano crystalline Al and AlN gets deposited on the inner surface of the plasma reactor. X-ray diffraction, Raman spectroscopy analysis, single crystal X-ray diffraction and TGA-DTA techniques are used to infer the purity of post process crystals as a hexagonal AlN. The average particle size using SEM was found to be around 30 mu m. The morphology of nanoparticles of Al and AlN, nucleated by gas phase condensation in a homogeneous medium were studied by transmission electron microscopy analysis. The particle ranged in size between 15 and 80 nm in diameter. The possible growth mechanism of crystalline AlN at the anode has been explained on the basis of non-equilibrium processes in the core of the plasma and steep temperature gradient near its periphery. The gas phase species of AlN and various constituent were computed using Murphy code based on minimization of free energy. The process provides 50% yield of microcrystalline AlN and remaining of Al at anode and that of nanocrystalline h-AlN and c-Al collected from the walls of the chamber is about 33% and 67%, respectively. (C) 2011 Elsevier B.V. All rights reserved.</p>10aCrystal morphology10aGrowth from high temperature solutions10aNitride10aSemiconducting aluminum compound1 aKanhe, Nilesh, S.1 aNawale, Ashok, B.1 aGawade, Rupesh, L.1 aPuranik, Vedavati, G.1 aBhoraskar, S., V.1 aDas, Asoka, K.1 aMathe, Vikas, L.  uhttp://library.ncl.res.in/content/understanding-growth-micro-and-nano-crystalline-aln-thermal-plasma-process-0