In this paper, a modeling method was introduced for SiC particle reinforced aluminum matrix composite. Micro-indentation technique was used to study the micro properties of both SiC particles and aluminum matrix with Micro-Compression-Tester. Mechanical properties like Young's modulus and hardness were calculated using Oliver and Pharr method. After repeated experiments, the average Young's modulus and the hardness of matrix and particle were calculated as 76.8 and 334.7 GPa, 1.58 and 32.56 GPa, respectively. During the indentation experiments on particle, the phenomenon of particle acting as “second indenter” was detected from the recorded P–h curves. Besides, the material elastic–plastic properties of matrix were analyzed using inverse method. Based on the micro material properties from indentation, the indentation processing of particle as second indenter has been simulated. Also, the simulation model at micro scale has been established by using such material properties for further investigation.

Poly (3-hexylthiophene) (P3HT) and aminated carbon microsphere (A-CMS) composite films with donor–acceptor architecture were prepared by spin-coating method, and the photovoltaic (PV) devices with a structure of ITO/PEDOT:PSS/P3HT:A-CMSs/Al were also fabricated. The structure and morphology of films were characterized by x-ray diffraction, Fourier transformation infrared spectrometry, ultraviolet-visible spectrophotometry, fluorescent spectrometry, and atomic force microscopy. The results indicate that A-CMSs exhibited a high LUMO energy level of −3.65 eV. The optimized blending ratio of P3HT:A-CMSs was 1:1. After annealing treatment, the intensity of absorption and the crystallization degree of the P3HT:A-CMS composite films enhanced. The polymer solar cells (PSCs) based on P3HT:A-CMS composite films showed a power conversion efficiency of 0.027% with an open circuit voltage of 0.80 V. It is suggested that A-CMS is a promising acceptor for PSCs. This would lay an experimental and theoretical foundation for the design of new acceptors for PV application.

The magnetic Fe–6.5 wt% Si powder was produced by gas atomization and its microstructure was also investigated. The secondary dendritic arm spacing (SDAS) is related to the droplet size, ${\rm{\lambda }} = 0.29 \cdot {D^{0.5}}$ , and the numerical solidification model was applied to the system, giving rise to the correlation of microstructure to the solidification process of the droplet. It is found that the solid fraction at the end of recalescence is strongly dependent on the undercooling achieved before nucleation; the chances for the smaller droplets to form the grain-refined microstructures are less than the larger ones. Furthermore, the SDAS is strongly influenced by the cooling rate of post-recalescence solidification, and the relationship can be expressed as follows, ${\rm{\lambda }} = 74.2 \cdot {\left( {\dot T} \right)^{ - 0.347}}$ . Then, the growth of the SDAS is driven by the solute diffusion of the interdendritic liquids, leading to a coarsening phenomenon, shown in a cubic root law of local solidification time, ${\rm{\lambda }} = 10.73 \cdot {\left( {{t_f}} \right)^{0.296}}$ .

Exploiting molecular dynamics simulation, this article investigates the dynamic process of atomic rearrangement in two metallic glasses (MGs), Cu50Zr50 and Fe80P20, which are well known as ductile and brittle MGs under compression, respectively. It was found that the local rearrangements can be identified clearly by the distribution of kinetic energy and atomic strain rate, and that they are always driven by several high-velocity atoms in the core and induce a large shear and tensile strain over a very short duration. The size, kinetic energy, strain rate, and cavitation rate of the clusters in Fe80P20 are markedly larger than those in Cu50Zr50, which explains the distinct strength and brittleness of these two MGs. This study further confirmed that localized rearrangement of atomic structure is the underlying mechanism of plastic deformation in MGs, which governs their macro-scale mechanical performance.

The effects of film thickness and surface orientation on melting behaviors of copper nanofilms were investigated by molecular dynamics simulations. A stepwise heating scheme was adopted to make sure that the nanofilms reached thermal equilibrium before further temperature increase. Melting of the nanofilms was monitored by examining the equilibrium potential energy, radial distribution function, and mean square displacement of the simulated nanofilms. From the simulation, the melting was observed to occur at a specific temperature within 1 K error, unlike the progressive melting process reported in the literature. The melted temperature and the latent heat of fusion of the nanofilms were found to increase with film thickness and approach the bulk value. The nanofilms with (111) surface have the highest melted temperature and the largest latent heat of fusion as compared to the ones with (001) and (011) surfaces, which could be explained by the lowest surface energy of (111) surface.

Scanning electron microscopic (SEM) observations revealed that individual and independent microcones of sp 3-bonded boron nitride grown by laser-activated plasma chemical vapor deposition were accompanied by ripple patterns spreading around them in the dimension of micrometers or sub-micrometers. The ripples were expanding equidistantly from each other and diminishing as they depart from a cone. The origin of the ripples was attributed to the interference of a direct laser cast on the plane surface and that reflected from the side of a cone; this model was satisfactorily in agreement with the SEM measurement, in which the side surface of a cone was mapped onto the plane surface surrounding the cone in the mathematical meaning of “bijection.” This micro-optical effect due to the wave nature of laser was considered to indicate and support the photochemically activated growth reactions in this process.

We investigated the persistent luminescence in europium-doped LiBaPO4. The persistent phosphors were synthesized via solid-state reaction method under mild reducing atmosphere. Its properties were investigated by x-ray diffraction, diffuse reflectance, photoluminescence, persistent luminescence, and thermoluminescence spectra. Under UV irradiation, broad-band persistent luminescence peaked at ∼470 nm was observed in the phosphors at room temperature. The effects of Eu2+ concentration on the persistent luminescence of LiBaPO4:Eu2+ were discussed. An energy level scheme was constructed to convey reasonable trapping and detrapping processes in the material.

Using epitaxy and the misfit strain imposed by an underlying substrate, it is possible to elastically strain oxide thin films to percent levels—far beyond where they would crack in bulk. Under such strains, the properties of oxides can be dramatically altered. In this article, we review the use of elastic strain to enhance ferroics, materials containing domains that can be moved through the application of an electric field (ferroelectric), a magnetic field (ferromagnetic), or stress (ferroelastic). We describe examples of transmuting oxides that are neither ferroelectric nor ferromagnetic in their unstrained state into ferroelectrics, ferromagnets, or materials that are both at the same time (multiferroics). Elastic strain can also be used to enhance the properties of known ferroic oxides or to create new tunable microwave dielectrics with performance that rivals that of existing materials. Results show that for thin films of ferroic oxides, elastic strain is a viable alternative to the traditional method of chemical substitution to lower the energy of a desired ground state relative to that of competing ground states to create materials with superior properties.

The nanogap is possibly the single most important physical entity in surface-enhanced Raman scattering. Nanogaps between noble metal nanostructures deliver extremely high electric field-enhancement, resulting in an extraordinary amplification of both the excitation rate and the emission rate of Raman active molecules situated in the gap. In some cases, the resulting surface-enhancement in the gap can be so high that Raman spectra from single molecules can be measured. Here, we briefly review some important concepts and experimental results on nanoscale gaps for SERS applications.