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Abstract: Powerful visible upconversion fluorescence intensities of Er3+ in novel bismuth gallate glasses (LKBBG) and common tellurite glasses (TZN) with low phonon energies and high refractive indices have been compared. Under the same measurement condition, Er3+-doped LKBBG glasses show the stronger upconversion emission intensities than Er3+-doped common tellurite glasses (TZN). The visible upconversion emission bands peaked at 531, 548 and 668nm have been confirmed that two photons contribute to these upconversion processes. The maximum phonon energy obtained in LKBBG glasses is 673cm−1, which is 65cm−1 lower than that in common tellurite glasses, indicating that LKBBG glasses almost possess the lowest maximum phonon energy in all of the oxide glasses. All analyses support that Er3+-doped LKBBG glasses are promising materials for fabricating visible upconversion devices. [Copyright &y& Elsevier]

Deposition current during fabrication plays an important role in the microstructure and properties of titanium alloy components prepared by multi-wire arc additive manufacturing (MWAAM) technology. In this study, Ti basic heterogeneous alloy with Ti-6.5Al-3.5Mo-1.5Zr-0.3Si (TC11) as the main component was deposited using the MWAAM method with the deposition current ranging from 360 A to 400 A. The effects of deposition current on the microstructural evolution, mechanical and corrosion properties of the MWAAM titanium alloys were investigated, and the process-microstructure-property relationship was analyzed. The results show that the microstructure of as-received Ti basic heterogeneous alloy was mainly composed of lamellar primary α phase (α P) and transformed β phase (β T), and increasing the deposition current during the MWAAM process would result in the increased width of α phase and the decreased aspect ratio of α phase. The mechanical properties of MWAAM-deposited specimens decrease with increasing current, which means that phase composition played a dominant role in determining hardness. When increasing the deposition current during the MWAAM process the ultimate tensile strength (UTS) decreased from 843.75 to 804.38 MPa. The MWAAM-deposited Ti basic heterogeneous alloy featured excellent corrosion properties, the corrosion potential of the best specimen was − 311 mV SCE and the corrosion current density was 1.23 × 10−8 Acm−2. This study provides a better understanding of the effect of deposition current on the targeted deposition property in the MWAAM process, which will contribute to future process control, improvement and optimization. • MWAAM-deposited Ti basic heterogeneous alloy was prepared by various deposition current. • Microstructure features and property was correlated with deposition current. • Deposition current of the Ti basic heterogeneous alloy was shown to affect the α + β microstructure. [ABSTRACT FROM AUTHOR]

Abstract: A series of VB x (x =0.1, 0.25, 0.5, and 1) are prepared by a mechanochemical reaction of elemental B and V powders and tested as alternative high capacity anodic materials for alkaline air batteries. The VB x (x =0.25, 0.5, and 1) anodes tested can deliver an extraordinary capacity of >2000mAhg−1, twice higher than the theoretical capacity of metallic Zn currently used as high capacity anodes in aqueous primary batteries. The strong discharge capabilities observed from electrochemically inert boron (B) and passive vanadium (V) in the VB x samples are suggested to result from a combined chemical interaction, in which the B atoms are electrochemically activated by bonding with V atoms to partially decrease the covalent stability of elemental B component. At the same time, the electrochemically activated B can alleviate, in turn, the anodic polarization of metallic V element by clamping the electrode potential to a region where elemental V is in active state. [Copyright &y& Elsevier]