4 research outputs found
An optimal sixteenth order family of methods for solving nonlinear equations and their basins of attraction
We propose a new family of iterative methods for finding the simple roots of nonlinear equation. The proposed method is four-point method with convergence order 16, which consists of four steps: the Newton step, an optional fourth order iteration scheme, an optional eighth order iteration scheme and the step constructed using the divided difference. By reason of the new iteration scheme requiring four function evaluations and one first derivative evaluation per iteration, the method satisfies the optimality criterion in the sense of Kung-Traub\u27s conjecture and achieves a high efficiency index . Computational results support theoretical analysis and confirm the efficiency.
The basins of attraction of the new presented algorithms are also compared to the existing methods with encouraging results
Porous ceramics based on natural mineral sources
Starting raw materials, clay and diatomite, from coal mine Kolubara, Serbia were purified using heat and chemical treatment. Porous silica ceramics were obtained at low forming pressure (40-80 MPa) and low sintering temperature (1000-1300 Ā°C) in air. Boric acid as a /ow-cost additive was used. Sintered samples have average pore si:ze diameters ranging of macroporous for clay 0.1-10 Ī¼m and for diatomite 0.05-5 Ī¼m. As-received and the obtained samples were characterized by XRD, SEM and mercury porosimetry measurements. Relations between mechanical characteristics of samples formed at different temperature were studied
Co/Mo bimetallic carbides with potential applications as catalyst support in pem fuel cells - synthesis and characterization
Co/Mo carbides were prepared by co-impregnation with aqueous solution of metal salts and sucrose into ordered mesoporous SBA-15 silica template using carbothermal hydrogen reduction. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDS) . Electrochemical characterization of obtained materials was performed by cyclic voltammetry in acide solution. Bimetallic CoMo carbide obtained by using carbothermal hydrogen reduction of Co Mo precursors is formed when the Co/Mo molar ratio is 1.0
Synthesis and characterization of co-mo bimetallic carbides
Co-Mo carbides were prepared by impregnation with aqueous solution of metal salts and sucrose into ordered mesoporous SBA-15 silica template using carbothermal hydrogen reduction. Bimetallic Co-Mo carbide obtained by using carbothermal hydrogen reduction of Co-Mo precursors is formed when the Co-Mo molar ratio is 1.0. The obtained samples were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. Electrochemical characterization of obtained materials wŠµre performed by cyclic voltammetry in acid solution