R. Sivakami

Bio: R. Sivakami is an academic researcher from Bharathidasan University. The author has contributed to research in topics: Computer science & Deep learning. The author has an hindex of 2, co-authored 2 publications receiving 95 citations.

Magnetically retrievable lepidocrocite supported copper oxide nanocatalyst (Fe–CuO) for N-arylation of imidazole

Abstract: A simple and efficient lepidocrocite-supported copper oxide catalyst (Fe–CuO) has been successfully prepared by a simple precipitation method in aqueous medium from readily available inexpensive starting materials and was used as a heterogeneous nanocatalyst for the N-arylation of imidazole with various aryl halides. The morphology, crystal structure, magnetic property, chemical state and surface area of the catalyst were studied. The N-arylation reaction was chosen to demonstrate the catalytic efficiency of the as-prepared Fe–CuO. Importantly, the catalyst can be easily recovered by magnetic attraction and its catalytic activity remains unaltered even after 6 consecutive cycles. Hence, Fe–CuO is an environmentally friendly, easily applicable and cost effective catalyst.

X-ray diffraction line profile analysis of nanostructured nickel oxide: Shape factor and convolution of crystallite size and microstrain contributions

Abstract: Nanostructured nickel oxide is synthesized through a chemical route and annealed at different temperatures. Contribution of crystallite size and microstrain to X-ray diffraction line broadening are analyzed by Williamson-Hall analysis using isotropic and anisotropic models. None of the models perform well in the case of samples with smaller average crystallite sizes. For sample with crystallite size ~3 nm all models show negative slope which is physically meaningless. Analysis of shape factor shows that the line profiles are more Gaussian like. Size-strain plot method, which assumes a different convolution of the crystallite size and microstrain contributions, is found to be most suitable. The study highlights the fact that the convolution of crystallite size and microstrain contributions may differ for samples and should be taken into account while analyzing the observed line broadening. Microstrain values show a regular decrease with increase in the annealing temperature.