The aim of this study was to explore whether nutrition supply can improve the drought tolerance of Moso bamboo under dry conditions. One-year-old seedlings were exposed to two soil water content levels [wellwatered, 70 ± 5% soil-relative-water-content (SRWC) and drought stress, 30 ± 5% SRWC] and four combinations of nitrogen (N) and phosphorus (P) supply (low-N, low-P, LNLP; low-N, high-P, LNHP; high-N, high-P, HNHP; and high-N, low-P, HNLP) for four months. Plant growth, photosynthesis, chlorophyll fluorescence, water use efficiency and cell membrane stability were determined. The results showed that drought stress significantly decreased total biomass, net-photosynthesis (Pn), stomatal-conductance (gs), leaf-chlorophyll-content (Chlleaf), PSII-quantum-yield (ΦPSII), maximum-quantum-yield-of-photosynthesis (Fv/Fm), photochemical-quenching-coefficient (qP), leaf-instantaneous-water-use efficiency (WUEi), relative-water-content (RWC), photosynthetic-N-use-efficiency (PNUE), and photosynthetic-P-use-efficiency (PPUE). N and P application was found to be effective in enhancing the concentration of leaf N, gs, and Pn while reducing the production of reactive oxygen species under both water regimes. Under LNHP, HNHP and HNLP treatments, the decreases in total biomass, Pn, Chlleaf and Fv/Fm of drought-stressed were less evident than the decreases under LNLP. The study suggests that nutrient application has the potential to mitigate the drastic effects of water stress on Moso bamboo by improving photosynthetic rate, water-use efficiency, and increasing of membrane integrity.

To improve the wear resistance of Titanium alloy, TiAl intermetallic claddings were fabricated on TC4 substrate using laser melting deposition technology. Optical microscope, scan electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction meter were applied to investigate the deposited TiAl layer and their interface with substrate. Using hardness tester and M-2000 wear testing machine, hardness, frictional coefficient and wear resistance of the TiAl layers and TC4 alloy were tested. It was indicated that the deposited TiAl layers were well integrated with TC4 substrate, γ-TiAl and Ti3Al dual phase microstructure was formed in the deposited layer. With higher hardness and lower friction coefficient, the deposited TiAl layer improved the wear resistance obviously comparing to TC4 titanium alloy substrate.

TiAl based intermetallic compound claddings were produced on TA15 alloy surface by using laser depositing technology to melt Ti-46Al-2Cr metal powders. An interface layer between TA15 substrate and the TiAl claddings was formed. The influence of laser power, scanning speed and number of cladding layers on the interface layer and the hardness of TiAl claddings were investigated. Higher laser power and lower scanning speed made the interface layer thicker. Increasing the laser power and especially the scanning speed could improve the hardness of the TiAl claddings. When the second TiAl layer was deposited, there was no interface layer formed between the two TiAl layers, but the hardness of the first layer decreased and the second TiAl layer was softer than the first layer due to the rough microstructure.

The population and size of porosities in three kinds of cast aluminum alloys, i.e. A713, A356T6-1 and A356T6-2, were statistically measured using a commercial software Spirit, and several distribution functions were tried to fit the cumulative pore size distribution data. It was found that a general extreme value (GEV) distribution function was the most appropriate function to quantify the cumulative pore size distribution in these cast aluminum alloys. The stress-number of cycles to failure (S-N) curves of these alloys were characterized by four point bend fatigue testing on MTS810 materials testing system, with the parameter f=20Hz, R=0.1, and in ambient air. The fatigue strength of A713, A356T6-1 and A356T6-2 aluminum alloy was measured to be 94.5 MPa, 150.6MPa and 117.3MPa respectively. The fatigue properties of these alloys could not be evaluated just by population and size distribution of the pores, the microstructure state, shape and position of pores, and other weakest links that may initiate a fatigue crack should be taken into account synthetically.