The development of highly active, cheap and robust oxygen reduction reaction (ORR) electrocatalysts to replace precious metal platinum is extremely urgent and challenging for renewable energy devices. Herein we report a novel, green and especially facile hydrogel strategy to construct N and B co-doped nanocarbon embedded with Co-based nanoparticles as an efficient non-precious ORR catalyst. The...

Replacement of precious platinum with efficient and low-cost catalysts for electrocatalytic hydrogen evolution at low overpotentials holds tremendous promise for clean energy devices. Here we report a novel type of robust cobalt-nitrogen/carbon catalyst for the hydrogen evolution reaction (HER) that is prepared by the pyrolysis of cobalt-N4 macrocycles or cobalt/o-phenylenediamine composites an...

statement of problem: element release from dental casting alloys into the oral environment is of clinical concern and is considered to be a potential health problem to all patients. purpose: the aim of this study was to investigate the metallic ion release of four base metal alloys. materials and methods: two ni-cr (minalux and supercast) and two co-cr alloys (minalia and wironit) were examined...

The aim of this investigation was to evaluate the metal-ceramic bonding of Au-1.6 wt% Ti alloy. Therefore, the coefficient of thermal expansion, modulus of elasticity, ceramic bonding strength, and hardness of Au-1.6 wt% Ti alloy were measured. The metal-ceramic interface was observed by EPMA to investigate its bonding mechanism. The Au-1.6 wt% Ti alloy showed a coefficient of thermal expansion...

The corrosion behaviour of three new non-toxic titanium alloys for use as biomaterials has been investigated. The corrosion current densities of these Ti alloys have low values, indicating a passive state that is stable with time. These values were calculated by using both direct and alternate current methods. The comparison with Ti–6Al–4V, widely used as biomaterial, shows slightly lower corro...

Adhesion promoting monomers — 5(4-vinylbenzyl) -2-thiobarbituric acid (5VS) , 9,10-epithiodecyl methacrylate (EP8MA) , 9,10-epithiodecyl 4-vinylbenzoate (EP8VB) , and 3,4-epithiobutyl 2,2-bis (methacryloyloxymethyl) propionate (EP2BMA) — were added to the MMA liquid of a MMA-PMMA/TBBO resin. Three dental precious metal alloys were butt-jointed together with the MMA-PMMA/TBBO adhesive resin, and...

1. Materials synthesis and characterization Catalyst synthesis: Commercially available TiO 2 , with the particle size ranging from 50 to 150 nm and in the B.E.T. surface area from 50 to 100 m 2 /g, was first treated in 0.5 M HCl solution for 24 hours to remove impurities. In a typical approach to the synthesis of the PANI-Fe-TiO 2 catalyst, 2.0 mL aniline was first dispersed in 0.5 M HCl soluti...

Adhesion promoting monomers -5-(4-vinylbenzyl)-2-thiobarbituric acid (5VS), 9,10-epithiodecyl methacrylate (EP8MA), 9,10-epithiodecyl 4-vinylbenzoate (EP8VB), and 3,4-epithiobutyl 2,2-bis(methacryloyloxymethyl)propionate (EP2BMA)--were added to the MMA liquid of a MMA-PMMA/TBBO resin. Three dental precious metal alloys were butt-jointed together with the MMA-PMMA/TBBO adhesive resin, and tensil...