The energetic particles bombardment can produce large internal stress in the zinc oxide (ZnO) thin film, and it can be used to intentionally modify the surface characteristics of ZnO films. In this article, we observed that the internal stress increased from −1.62 GPa to −0.33 GPa, and the naturally wettability of the textured ZnO nanostructured films changed from hydrophobicity to hydrophilicity. According to analysis of surface chemical states, the naturally controllable wetting behavior can be attributed to hydrocarbon adsorbates on the nanostructured film surface, which is caused by tunable internal stress. On the other hand, the interfacial water molecules near the surface of ZnO nanostructured films have been identified as hydrophobic hydrogen structure by Fourier transform infrared/attenuated total reflection. Moreover, a remarkable near-band-edge emission peak shifting also can be observed in PL spectra due to the transition of internal stress state. Furthermore, our present ZnO nanostructured films also exhibited excellent transparency over 80% with a wise surface wetting switched from hydrophobic to hydrophilic states after exposing in ultraviolet (UV) surroundings. Our work demonstrated that the internal stress of the thin film not only induced natural wettability transition of ZnO nanostructured films, but also in turn affected the surface properties such as surface chemisorption.

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In this paper, both the modal testing method and amplitude-fluctuation (AF) electronic speckle pattern interferometry (ESPI) were used to measure the resonant frequencies, mode shapes, phase distribution and whole-field displacements of composite plates with and without defects. Square-and circular-shape defects of two different sizes were used in the composite plates. Two different stacking sequences of the composite plates were adopted, i.e. [0/90] 3S and [±45] 3S . Composite plates containing simulated defects located from the 3 rd to 6 th layer numbering from the top of the plates were fabricated, respectively. It was found that both the anomaly of the AF-ESPI fringe pattern around the defect and the decrease of resonant frequencies due to the defect are feasible ways to detect the existence of the defect. To explain the local effect of the defect at higher frequencies, vibration theory of thin plate with fixed ends for the square shape defect was employed.

In this paper, we have (1) built a micro flow network that mimics micro vessels and visualized the flow inside utilizing both experimental and CFD approaches, (2) developed a model, which considering both the inertial forces caused by flow convection and the diffusion resulting from Brownian motion, to evaluate the entrapment probability of nanoparticles with various particle sizes and channel geometries from micro flow field into nanochannels. In the experimental results, the spatial resolution of about 2 μm is employed to resolve the near-wall flow field with 50% interrogation spot overlapping by using μPIV. The most significant deviation is about 5% between the experimental and simulation results. Finally we used Stokes-Einstein equation to estimate the entrapment probability of nanoparticles with various particle sizes and channel geometries.