相关论文: Exploring the behavior of vanadium under high-pres…
Vanadium sesquioxide, V2O3, is a prototypical metal-to-insulator system where, in temperature-dependent studies, the transition always coincides with a corundum-to-monoclinic structural transition. As a function of pressure, V2O3 follows…
An elastic-visco-plastic thermomechanical model for the simulation of cold forming and subsequent sintering of ceramic powders is introduced and based on micromechanical modelling of the compaction process of granulates. Micromechanics…
Solidification as a first order phase transition is described in the Landau theory by the same equation as tricritical phenomena. Here, the solidification or melting temperature against pressure curve is modelled to end at a tricritical…
A multiscale numerical model based on nonequilibrium thermal effect for melting of metal powder bed subjected to constant heat flux is developed. The volume shrinkage due to density change is taken into account. The nonequilibrium model is…
Vanadium is a transition metal with multiple oxidation states and V2O5 is the most stable form among them. Besides catalysis, chemical sensing and photo-chromatic applications, V2O5 is also reported to exhibit a semiconductor to metal…
Polyhydrides have been shown to form novel structures at high pressure, which may be found in the interiors of giant planets. With density functional molecular dynamics simulations we studied the behavior of ammonium polyhydride compounds…
Compacted unsaturated swelling clay is often considered as a possible buffer material for deep nuclear waste disposal. An isotropic cell permitting simultaneous control of suction, temperature and pressure was used to study the…
We report the results of a large scale computer simulation of a binary supercooled Lennard-Jones liquid. We find that at low temperatures the curves for the mean squared displacement of a tagged particle for different temperatures fall onto…
We report on our recent progress in the manipulation and cooling of a magnetically guided, high flux beam of $^{87}{\rm Rb}$ atoms. Typically $7\times 10^9$ atoms per second propagate in a magnetic guide providing a transverse gradient of…
The precise measurements of vortex melting point towards a need to develop a quantitative theoretical description of thermal fluctuations in vortex matter. To tackle the difficult problem of melting, the description of both the solid and…
We present the structural and dynamical studies of layered vanadium pentaoxide (V2O5). The temperature dependent X-ray diffraction measurements reveal highly anisotropic and anomalous thermal expansion from 12 K to 853 K. The results do not…
Pressure-induced phase transitions in orthovanadates have led to interesting physical phenomena. The observed transitions usually involve large volume collapses and drastic changes in the electronic and vibrational properties of the…
Hydrogen is the most abundant element in the universe, and its properties under conditions of high temperature and pressure are crucial to understand the interior of of large gaseous planets and other astrophysical bodies. At ultra high…
The melting temperature ($T_m$) of a solid is generally determined by the pressure applied to it, or indirectly by its density ($n$) through the equation of state. This remains true even for helium solids\cite{wilk:67}, where quantum…
Melting of rhombohedral boron subnitride B13N2 has been studied in situ at pressures to 8 GPa using synchrotron X-ray diffraction and electrical resistivity measurements. It has been found that above 2.6 GPa B13N2 melts incongruently, and…
We report studies of the growth of solid hcp \4he at pressures higher than the bulk freezing pressure using a cell design that allows us to inject atoms into the solid. Near the melting curve during injection we observe random events during…
The superconducting and structural properties of elemental strontium metal were investigated under pressures up to 60 GPa while maintaining cryogenic conditions during pressure application. Applying pressure at low temperatures reveals…
We construct a simple thermodynamic model to describe the melting of a supported metal nanoparticle with a spherically curved free surface both with and without surface melting. We use the model to investigate the results of recent…
The equations of state at room temperature as well as the energies of crystal structures up to pressures exceeding 100 GPa are calculated for Na and K . It is shown that the allowance for generalized gradient corrections (GGA) in the…
Several important geophysical features such as heat flux at the Core-Mantle Boundary or geodynamo production are intimately related with the temperature profile in the Earth's core. However, measuring the melting curve of iron at conditions…