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The oxidation mechanism of steels in liquid-lead alloys (lead or lead-bismuth) was studied. Parametric dependencies of oxidation, including oxygen-concentration effects, oxidation-rate constant and corrosion-rate effects, are analyzed. An oxidation model is developed based on the assumptions that the chemical reactions are at equilibrium locally, and scale removal is due to mass-transfer corrosion. The model shows that outward-iron diffusion in the solid phase (oxide layer) controls the oxide growth and mass-transfer rate in the flowingboundary layer determines the corrosion-product transport in the liquid phase (liquid-lead alloy). The oxide thickness depends on both the parabolic oxidegrowth-rate constant and the mass-transfer-corrosion rate. For long-term operation, the outer layer of a duplex-oxide layer can be completely removed by flowing lead alloys and it is expected that a pure-chromium-oxide layer forms underneath the Fe-Cr spinel if iron is heavily depleted. The oxide thickness and steel weight change are very different from those of the pure parabolic law and they are classified into distinct and universal categories. The model is validated partially by application to interpreting the measured oxide behavior of several steels in a lead-bismuth eutectic-test loop.

A thermoplastic forming (TPF) map of a Zr 35 Ti 30 Be 26.75 Cu 8.25 bulk metallic glass was constructed through systematic hot-embossing experiments, spanning a wide range of strain rates and temperatures in the supercooled liquid region. By comparison with the corresponding deformation map, it is found that Newtonian flow, non-Newtonian flow and inhomogeneous flow regions correspond well to fully filled, partially filled and non-filled regions, respectively, in the hot-embossing TPF map. Furthermore, the spatio-temporally homogeneous flow facilitates the thermoplastic formabillity of the Zr-based bulk metallic glass, which is rationalized in terms of free volume theory as well as by finite element simulations. Finally, our results are corroborated by potential application tests.

We investigate the pairwise quantum correlation, characterized by quantum entanglement (QE) and quantum discord (QD), of a two-dimensional Ising-Heisenberg model on a planar doubly decorated lattice. At zero temperature, the concurrence (a measurement of pairwise entanglement) and the QD are related to the correlation function qxx and the staggered magnetization δSz, respectively, and both of them indicate the quantum phase transition (QPT) of the system. However, in a finite-temperature phase transition, all the pairwise entanglement vanishes thus it fails to detect the critical temperature TC , while the derivative of QD diverges at TC . This shows clearly that QD can capture the signal of phase transition in a separable state, thus it has a broader scope of application than QE in detecting phase transitions.