A 3D NiCo2O4 hierarchical architecture composed of interlaced and self-stacked 2D nanoflakes is realized as a urea oxidation reaction catalyst for the generation of green energy in direct urea fuel cells.

Uniform sized Ni-Co alloy nanoparticles were effectively confined over the active channels of mesoporous silica nanoparticles (MSN) using a simple chemical reduction method, and the resultant nanostructures exhibited a spherical configuration with a mean diameter of 5 nm. The face-centered cubic (fcc) crystalline structure of Ni and Ni-Co alloy nanoparticles and the amorphous structure of MSN matrix were identified from the diffraction patterns. The MSN supported catalysts were exploited as electrochemical probes for the detection of glucose, and the controlled morphology, smaller particle size, uniform dispersion and active surface of the Ni-Co alloy nanoparticles improved the excellent electrocatalytic activity of MSN/Ni-Co toward the electrooxidation of glucose. The MSN/Ni-Co nanocomposite exhibited good analytical performance for glucose detection, with a linear response ranging from 0.001 to 5.0 mM, a low detection limit of 0.39 mM and a high sensitivity of 536.62 mA mM À1 cm À2 . The results of the performed experiments also demonstrated the good reproducibility, long-term stability and high selectivity of the fabricated sensors without the influence of interference from other oxidizable species, which may represent a technically sound and economical new avenue in nonenzymatic glucose sensor applications.

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This case report describes endodontic treatment completed in a peg-shaped maxillary lateral incisor, with single root and five root canals of which, one is due to dens invaginatus. Cone beam computed tomogram scanning confirmed the unique morphology of the tooth. New nomenclature for the five canals is proposed.

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