A symptom of chilling injury is development of water deficit in shoots, resulting from an imbalance of water transport and transpiration. In this work, two rice varieties (Oryza sativa L. var. Wasetoitsu and Somewake) seedlings were chilled at 7 o C, followed by recovery at 28 o C. Based on the growth phenotype and electrolyte leakage tests, Somewake was shown to be a chilling-tolerant variety, and Wasetoitsu a chilling-sensitive one. The chilling stress reduced markedly the relative water content (RWC) of leaves, accumulative transpiration and osmotic root hydraulic conductivity (Lp) in both varieties. But when returned to 28 o C, the water relation balance of Somewake recovered better. The mRNA expression profile of all the 11 plasma membrane intrinsic proteins (PIPs), a subgroup of aquaporins, was subsequently determined by real-time reverse transcription (RT)-PCR with TaqMan-minor grove binder (MGB) probes derived from rice var. Nipponbare during chilling treatment and recovery. Most of the PIP genes was down-regulated at the low temperature, and recovered at the warm temperature. The relative expression of some PIPs in both Somewake and Wasetoitsu decreased in parallel during the chilling. However during the recovery, the relative expression of OsPIP1;1, OsPIP2;1, OsPIP2;7 in shoots and OsPIP1;1, OsPIP2;1 in roots were significantly higher in Somewake than Wasetoitsu. This supports the role of PIPs in re-establishing water balance after chilling conditions. We discuss the diversified roles played by members of the aquaporin PIP subfamily in plant chilling tolerance depending on aquaporin isoforms, plant tissue and the stage of chilling duration.

the inner flow fields of twelve Hema-type ATY nozzles which have different structure and parameters are simulated by the Fluent software, which is based on the CFD (Computational Fluid Dynamics) theory.Then the simulation results are analyzed，through wich the best designed nozzle is determined.

Send laser cladding experiments to the substrate surface in 16Mn in the Synchronous way. By different laser cladding parameters on the microstructure and mechanical properties under the comparative analysis, to make a more detailed discussion of laser cladding power and scanning speed on the quality of laser cladding. Different process parameters on the microstructure of cladding layer and the cladding layer of particle distribution and the tissue distribution of species .We get to the study that type and distribution of the cladding layer microstructure and tissue distribution of tungsten carbide hard phase. We get regular pattern that technological parameter has an effect on the quality of cladding layer. We can came to the conclusion that the best cladding process parameters is in the power of 3.0KW and cladding speed 1000mm/min.