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Research on the influence of alloy concentration and distribution on bimetallic cluster plays a key role in exploring new structural material. This paper studies the melting process of icosahedral bimetallic cluster (PdPt)₁₄₇ with different Pt concentrations and different atomic distributions by using molecular dynamics with an embedded atom method. The results indicate that the mixed Pd–Pt cluster shows an irregular phenomenon between 580 and 630 K, i.e. the atomic energy decreases with the increase of temperature. This is because the surface energy of Pd is lower than that of Pt; the decreased energy due to Pd atomic segregation is larger than the increased energy due to heating during the segregation process. In addition, the temperature of Pd atomic segregation is strongly related to Pt concentration. This leads to that Pd atoms prefer to remain on the surface even after the cluster melted.

Electron energy loss spectroscopy has been used for the investigation of the surface and bulk plasmon excitations depending on the heating in the ultra-thin layers of ordering Pt₈₀Co₂₀(111) alloy from the primary electron beam energies E₀ ranging from 200 to 650 eV. Thermo-induced shift of plasmon energy and damping of intensity line of the surface plasmon relative to the bulk plasmon were observed. With an increase in alloy heating, the energy of surface and bulk plasmons is shifted with lowering energy in the whole range E₀ and the higher the temperature the higher the shifts of plasmon energy. The physical processes that can influence on the energy shift of plasmon oscillations in the energy loss spectra at heating are considered. The relationship between the damping of oscillating concentration depth profile and the surface plasmon damping at heating was established.

Changes in the thermomechanical properties of fiber-reinforced concrete (FRC) exposed to fire are fundamentally affected by the type and volume fraction of fibers. Because the loss of FRC load-bearing capacity is mainly caused by structural damage, a new numerical procedure based on a modified method of discontinuous boundary elements (DBEM) is proposed, which is modified to include thermomechanical processes in concrete together with the effect of fibers. DBEM allows the reader to visually track the location and extent of material damage.

The electrostatic electron Bernstein wave (EBW) can provide localised on- and off-axis heating and current drive in typically overdense (high-β) spherical tori (ST) where the usual electromagnetic EC modes are cut-off. Hence, the EBW is a candidate for plasma control and stabilisation in such devices. We present here a modelling of EBW heating and current drive in realistic ST conditions, particularly in typical NSTX equilibria and in model equilibria for NHTX [1] and MAST Upgrade [2,3]. The EBW injection parameters are varied in order to find optimized scenarios and possible ways to control the deposition location and the driven current. It is shown that EBWs can be deposited and efficiently drive current at any radial location.