This work investigates the fracture behavior of shape memory alloy NiTi (50.7 at. pct Ni) at room temperature. Macroscopic mechanical tests, microscopic in situ observations of tensile fracture processes by scanning electron microscopy (SEM), and detailed analyses of fracture surfaces were carried out. The results reveal that specimens with different thicknesses show various shape memory effects and superelasticities. The main crack with a quasi-cleavage mode that combines cleavage with ductile tearing is initiated at the notch tip and is stress-control-propagated in line with the direction of the maximum normal stress. The microstructure has little effect on the direction of crack propagation, but coarser substructures show lower resistance to the crack propagation. In specimens with various types of notches, various notch acuities present different effects on the crack initiation and propagation and result in different fracture behaviors.

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A novel phosphor, Gd2MoB2O9:Eu3+ has been synthesized by solid-state reaction and its photoluminescence in UV-VUV range are investigated. A sharp excitation band is observed in the region of 120–135 nm, which is related to the charge-transfer (CT) band of Gd3+. The broad band around 135–160 nm can be assigned to the BO3 host absorption. The broad bands around 248 nm are assigned to the CT band of Eu3+-O2-. The phosphors emit strong red luminescence centered at about 591 nm, 614 nm and 626 nm due to the5D0–7F1 and 5D0–7F2 transitions of Eu3+. The main emission peak under 254 and 147 nm excitations also shows different shifts with increasing Eu3+ concentration. This could be due to the different luminescence sites selected at high doping concentrations of Eu3+. Gd2MoB2O9:Eu3+ shows the pure red emission under both 254 and 147 nm excitations.

One-dimensional BaAl12O19:Mn2+ nanofibers were fabricated by electrostatic spinning method. The effects of some factors on the product preparation were investigated, such as the pH value of precursors; the proportion of citric acid; calcination temperatures, and then the optimal synthetic conditions was obtained. The calcination temperatures of optimal sample is only 1100 °C, less about 400 °C than that of the traditional solid state reaction method. X-ray diffraction, scanning electron microscopy, transmission electron microscopy and photoluminescence spectroscopy were adopted to detect the structure, grain size, morphology and optical properties of the nanofibers, respectively. The fiber samples with good crystallinity consist of a great quantity of nanoparticles. The size of each nanoparticle is below 50 nm and the fiber diameter is about 400 nm. Possible formation process of the nanofibers by electrostatic spinning was also discussed.