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SUMMARYWe investigated the main water entry sites during imbibition of Sapium sebiferum seeds, and the relationship between seed coat structure and water uptake. Seed coat structure was observed using a scanning electron microscope (SEM), while dye-tracking and blocking experiments were used to determine the major sites of water entry into S. sebiferum seeds. Water uptake by intact or cracked seeds was also compared. SEM images showed that, from the exterior to the interior, the seed coat of S. sebiferum consisted of three layers: the waxy cuticle, the palisade layer, and the parenchymal layer. The results of water uptake studies revealed that cracked seeds absorbed more water and reached saturation faster than intact seeds. This indicated that the seed coat of S. sebiferum was permeable, but could delay water uptake. The results of the blocking experiments confirmed that S. sebiferum seed could absorb water throughout the entire seed coat, but that the major site of water absorption was the middle part o...

Well-aligned ZnO nanorods are obtained by a liquid phase epitaxial growth on the indium-doped tin oxide glass deposited with a ZnO thin film as the seed layer, which is prepared by combining a sol–gel process and a spin coating technique. The effects of water content in the sol and heat treatment temperature on the properties of the ZnO thin film are investigated. Relationship among the seed layer, the growing time, the growing temperature, the concentration of Zn2+ in the solution, the anions in the solution and the resulting ZnO nanorods are discussed in detail. X-ray diffraction analysis and scanning electronic microscopy are employed to characterize the structural and morphological properties of the resulting ZnO nanorods. Results indicate that the ZnO nanorods with a preferred orientation show a single crystal with a wurtzite structure in the direction of [0001], the diameter of the ZnO nanorods seems to depend on the size of the seed grain, while the length of the ZnO nanorods is determined by the growing time and the growing temperature.