相关论文: Phase transformation on heating of an aged cement …
The Latent heat storage technology is being used worldwide to bridge the gap between supply and demand of energy. The material store energy during the charging process (melting) and releases energy during the discharging process…
From soft polymeric gels to hardened cement paste, amorphous solids under constant load exhibit a pronounced time-dependent deformation called creep. The microscopic mechanism of such a phenomenon is poorly understood in amorphous materials…
The through-process microstructural effects in A356 subjected to rotary forming at elevated temperatures have been investigated. Macro and micro-hardness testing have been used extensively to track changes in the material from the as-cast…
In this paper we describe a new model for solidification with heat flux using the phase field crystal (PFC) framework. The equations are thermodynamically consistent, in the sense that the time rate of change of the entropy density is…
Modeling phase change problems numerically is vital for understanding many natural (e.g., ice formation, steam generation) and engineering processes (e.g., casting, welding, additive manufacturing). Almost all phase change materials (PCMs)…
We describe experiments where 2D atomic hydrogen gas is compressed thermally at a small "cold spot" on the surface of superfluid helium and detected directly with electron-spin resonance. We reach surface densities up to 5e12 1/cm^2 at…
A generalized non-relativistic Fermi-liquid approach was used to find analytical formulas for temperatures $T_{c,1}(n,H)$ and $T_{c,2}(n,H)$ (which are functions nonlinear of density n and linear of magnetic field H) of phase transitions in…
We present a kinetic model for solid state phase transformation (alpha<-->beta) of common zirconium alloys used as fuel cladding material in light water reactors. The model computes the relative amounts of beta or alpha phase fraction as a…
The properties of hydrogen-helium mixtures at Mbar pressures and intermediate temperatures (4000 to 10000 K) are calculated with first-principles molecular dynamics simulations. We determine the equation of state as a function of density,…
The $\beta$-relaxation associated with the sub-glass transition temperature ($T_{\text{g},\beta}$) is attributed to fast, localised molecular motions which can occur below the primary glass transition temperature ($T_{g\alpha}$). Despite…
Values of water permeability for cementitious materials reported in the literature show a large scatter. This is partially attributed to the fact that materials used in different studies are different. To eliminate the effects of cements,…
Cement hydration products were studied as influenced by the hydration conditions (hydration time in liquid phase; relative humidity, RH, in gaseous phase). The formation of calcium hydroxide (portlandite, P) and its transformation to…
We explore experimentally the fluidization of vertically agitated PMMA spheres wetted by liquid $^4$He. By controlling the temperature around the $\lambda$ point we change the properties of the wetting liquid from a normal fluid (helium I)…
Physical aging of glycerol following temperature jumps is studied by dielectric spectroscopy at temperatures just below the glass transition temperature. The data are analyzed using two single-parameter aging tests developed by Hecksher et…
The one-dimensional (1D) Stefan problem is a prototypical heat and mass transfer problem that analyzes the temperature distribution in a material undergoing phase change. In addition, it describes the evolution of the phase change front…
Ceramics are typically brittle at ambient conditions due to their covalent or ionic bonding and limited dislocation activities. While plasticity, and occasionally superplasticity, can be achieved in ceramics at high temperatures through…
We performed an X-ray diffraction experiment while palladium bulk absorbed and desorbed hydrogen to investigate the behavior of the crystalline lattice during the phase transition between the $\alpha$ phase and $\beta$ phase. Fast growth of…
We study the latent heat of the liquid-gas phase transition in symmetric nuclear matter using self-consistent mean-field calculations with a few Skyrme forces. The temperature dependence of the latent heat is rather independent of the…
A mathematical model has been developed to simulate the kinetic and thermal behaviour of a porous solid pellet undergoing chemical reaction with a gas. The model describes the chemical reaction itself, the transfer of the gaseous species…
We couple the recently developed self-learning metabasin escape algorithm, which enables efficient exploration of the potential energy surface (PES), with shear deformation to elucidate strain-rate and temperature effects on the shear…