On the influence of active element content on the thermal conductivity and thermal expansion of Cu-X (X = Cr, B) diamond composites

Thermodynamic optimization of the B–Fe system

Critical thermodynamic evaluation and optimization of the Fe–B, Fe–Nd, B–Nd and Nd–Fe–B systems

The available experimental observations on the equilibrium phase diagram and on the mixing thermodynamics of the Ni–B system have been compiled and critically evaluated. An internally consistent set of thermodynamic model parameters for the solution phases as well as for the intermetallic compounds has been estimated by means of a least squares method and the Lukas program, simultaneously using phase diagram and thermodynamic observations. The complete phase diagram from pure boron to pure nickel at 600–2100°C was calculated using a thermodynamic approach and the thermodynamic mixing properties of the solution phases, as modelled by Redlich–Kister polynomials. The Gibbs energies of formation of the intermetallic phases, described as stoichiometric compounds, have been estimated from the experimental data and refined by means of a least squares treatment. No reliable observations are available on the alloys above 60 at.-%B and, thus, an extrapolated phase diagram has been calculated for the boron ...

Thermodynamic assessment of Ni–B phase diagram

Copper (Cu) is a commercial catalyst for the synthesis of methanol from syngas, low-temperature water gas shift reaction, oleo-chemical processing, and for the fabrication of graphene by chemical vapor deposition. However, high barriers for C–H bond activation and the ease of formation of carbon/graphene on its surface limits its application in the utilization and conversion of methane to bulk chemicals. In the present paper, using first-principles calculations, we predict that Cu catalyst doped with a monolayer of sub-surface boron (B–Cu) can efficiently activate the C–H bond of methane and can selectively facilitate the C–C coupling reaction. Boron binds strongest at the sub-surface octahedral site of Cu and the thermodynamic driving force for the diffusion of B from an on-surface to the sub-surface position in Cu is stronger than that for the experimentally synthesizable B–Ni (sub-surface boron in nickel) catalyst, providing a proof of concept for the experimental synthesis of this novel catalyst. Addi...

Sub-Surface Boron-Doped Copper for Methane Activation and Coupling: First-Principles Investigation of the Structure, Activity, and Selectivity of the Catalyst

Activities of boron in the binary Fe-B, Co-B, and Cu-B melts have been directly determined by the electromotive force (emf) measurement. Boron-saturated liquid Cu-B alloy was used as the reference electrode and a ternary 28 wt pct Al2O3-29 wt pct B2O3-43 wt pct CaO oxide melt was used as the electrolyte. Deviations of the boron activities from Raoult's law have been found largely negative for the Fe-B and Co-B systems but largely positive for the Cu-B system. Boron activities calculated from the literature data have not been in good agreement with the measured data. Activities of iron, cobalt, and copper have been calculated from the obtained boron activities by means of the Gibbs-Duhem equation. Some modifications to the liquidus curves on the Fe-B and Co-B phase diagrams have been presented.

Activities of boron in the binary Fe-B, Co-B, and Cu-B melts

Mesures de l'activite de B dans les alliages liquides Ni-B-C satures en carbone entre 1100 et 1400°C a l'aide d'une pile electrochimique

M. Yukinobu

Papers

Activities of boron in the binary Fe-B, Co-B, and Cu-B melts

Activity of boron in Ni-B-C melts saturated with carbon