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• Heterogeneous microstructure was easily formed by DDRX during hot rolling. • Different storage energy can cause uneven grains during SA at high temperature. • Larger grains continued to annex adjacent smaller grains for the abnormal growth. • Adopting stepped heating from low to high temperatures can obtain uniform grains. Series of solution annealing experiments and quasi in-situ observation were employed to investigate the grain growth behaviors based on the heterogeneous microstructure with deformation bands and dynamic recrystallization (DRX) grains in hot rolled 316H austenitic stainless steel (ASS). It was worked out that during early stage of direct heating at high temperature of above 1000℃, the initial static recrystallized grains with different sizes would nucleate rapidly on the deformation band and DRX grains. With the extension of holding time, they gradually grew up to develop into the grains with large size differences, during which the larger grains continued to swallow adjacent smaller grains even presenting abnormal annexation or growth. However, by adopting stepped heating from low to high temperature, the grains evenly grew and presented relatively uniform distribution, which provides new idea for regulating grain size in manufacturing heavy ASSs. [ABSTRACT FROM AUTHOR]

• The spall strength of tungsten alloy is weakly dependent on the peak stress. • With the increase of impact stress, cleavage fracture replaces intergranular fracture as the main fracture mode. • Twins appear near the crack of tungsten particles, which hinders the further propagation of cracks. • The {100}, {110} and {111} planes are the most potent macroscopic cleavage planes for the tungsten alloy. In this study, plate-impact experiments are conducted using tungsten heavy alloy (WHA) to obtain the free-surface velocity profiles under shock stress of 6–23 GPa. By analyzing the velocity wave profile, it is demonstrated that the spall strength is weakly dependent on the peak stress. The microstructure of the recovered WHA is well characterized and it's observed that intergranular fracture and cleavage are the primary fracture mechanisms. Deformation twins are sparsely distributed near the cleavage crack. The existence of twin boundary not only affects crack propagation but also regulates the crack path and reinitiates the cleavage propagation direction on the twin boundary. The macroscopic cleavage facet planes are detected to be {100}, {110} and {111} at all shock stress. [ABSTRACT FROM AUTHOR]

The porous Ag 3 PO 4 architectures (PAs) were synthesized by a facile self-sacrificial route through the simultaneous acid-etching and anion exchange reactions between Ag 2 CO 3 and H 3 PO 4 at room temperature. The resulting samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–vis diffuse reflectance spectroscopy. The Ag 3 PO 4 PAs exhibited superior photocatalytic activity for the degradation of methyl orange (MO) under visible light irradiation, which were much higher than that of solid Ag 3 PO 4 counterpart. This study could provide a general approach for the synthesis of other porous semiconductors from carbonate precursor. [ABSTRACT FROM AUTHOR]

Abstract: PX-phase PbTiO3 (PT) nanowires were synthesized by microwave-hydrothermal process, and their microstructures were characterized by electron microscopy. The PX-phase PT nanowires exhibit acicular morphology with diameter sizes of 20–80nm and length over 1µm. They tend to grow into a regular structure with parallel arrangement along their long axis in the [001] direction. Selected area electron diffraction patterns demonstrate the PX-phase PT nanowires with a 3-fold modulated periodicity along the [110] direction and a 4-fold modulated periodicity in the [001] direction. These results were also confirmed by the high-resolution transmission electron microscopy images. [Copyright &y& Elsevier]

Si/C multilayer films with different crystal structures were deposited on Cu substrate using magnetic sputtering, and the diffusion behaviors of Li + in the films were compared to those of XRD, SEM, and electrochemical cycling. The results show that Li + can completely diffuse into a 300 nm amorphous Si/C multilayer thin film under a charge/discharge current of 350 μA cm −2 , while in the case of crystallized films with [311] preferred orientation, a poor diffusion character was observed even under a current of 273 μA cm −2 . [ABSTRACT FROM AUTHOR]

Abstract: Polymerization crystalline colloidal arrays (PCCA) were fabricated by light polymerization method. Microstructures of polymerization crystalline colloidal arrays were observed by SEM. The results show that the microspheres in the PCCA form into a face-centered cubic structure with (111) plane parallel to the surface of the quartz cell. In addition, the influence of photonic band gap on photoluminescence of dyes was also investigated in the PCCA. Suppression of the emission was observed if the photonic band gap overlapped with the dyes emission band in the PCCA. Suppression of the emission was attributed to the photon trapping of the Bragg reflection in the PCCA. [Copyright &y& Elsevier]