Bunches of needle-shaped silicon carbide (SiC) nanowires were grown from commercially available SiC powders in thermal evaporation process and using iron as catalyst. Their structure and chemical composition were studied by Raman spectroscopy and high-resolution transmission electron microscopy. The powder of these nanowires may be easily dispersed, and was used to form samples of field electron emitters. The needle shape of individual nanowires is well-suited to field electron emission. Stable emission with current density of 30.8 mA/cm2 was observed at fields as low as 9.6 V/μm, and current density of up to 83 mA/cm2 was recorded.

Variable angle tow (VAT) placement techniques provide the designer with the ability to tailor the point-wise stiffness properties of composite laminates according to structural design requirements. Whilst VAT laminates exhibit-

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The enhanced photocurrent responses and dramatic antiphotocorrosion performance of CdS hybrid were obtained by formation of triple heterojunction (TH), i.e., n-CdS/n-TiO 2 /p-BDD:n-TiO 2 cube tubes were vertically grown on p-type boron-doped diamond (BDD) film. Then n-CdS nanoparticles (NPs) were randomly assembled onto the surface of TiO 2 and BDD, forming a film of CdS NPs. This triple heterojunction CdS hybrid reveals 36.5% improvement of initial photocurrent and 78% reduction of photocorrosion rate in contrast with that of the coupled CdS/TiO 2 hybrid, which has only single heterojunctions (SH). The mechanisms of TH on charge separation and transport during the photocatalytic reaction have been emphasized. Except for the CdS/TiO 2 (n−n) heterojunction, another two p−n heterojunctions, i.e., p-BDD/n-CdS and p-BDD/n-TiO 2 exist in the TH. The conduction band (CB) position of TiO 2 is lower than the corresponding band positions of CdS and BDD, so TiO 2 can act as an acceptor for the photogenerated electrons. Also, the valence band (VB) position of BDD is higher than those of CdS and TiO 2 , so BDD can act as a sink for the photogenerated holes. Under simulated solarlight, the photogenerated electrons on the conduction band (CB) of CdS flow to the CB of TiO 2 , whereas the photogenerated holes on valence band (VB) CdS and TiO 2 inject to the VB of BDD. It promotes charge separation and leaves not enough holes on CdS to cause photoanodic corrosion, leading to the enhancement of photocurrent responses and the remarkable inhibited photocorrosion.

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This paper investigates the vibration characteristics of the coupling system of a microscale fluid-loaded rectangular isotropic plate attached to a uniformly distributed mass. Previous literature has, respectively, studied the changes in the plate vibration induced by an acoustic field or by the attached mass loading. This paper investigates the issue of involving these two types of loading simultaneously. Based on Lamb's assumption of the fluid-loaded structure and the Rayleigh-Ritz energy method, this paper presents an analytical solution for the natural frequencies and mode shapes of the coupling system. Numerical results for microplates with different types of boundary conditions have also been obtained and compared with experimental and numerical results from previous literature. The theoretical model and novel analytical solution are of particular interest in the design of microplate-based biosensing devices.

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A rapid and robust semi-analytical model is developed based on the Rayleigh-Ritz energy method for the buckling analysis of blade stiffened variable stiffness panels. The method includes the often neglected, yet important, stiffener ange in the analysis by not only accounting for the local increase in stiffness but, for the first time in a Rayleigh-Ritz method, allowing the structure to respond in a discontinuous manner at the location of the stiffness discontinuity. This is achieved by discretizing the panel at locations of discontinuities such as ange edges and assigning each region individual shape functions thus preventing a global C1-continuous response in the buckled mode shape. The model is shown to be in excellent agreement with, and computationally efficient when compared to, a commercial FEA package. The model is then used in a genetic algorithm optimization study to design blade stiffened variables stiffness panels by applying practical design and failure constraints. Results are compared with optimized conventional stiffened panels and for the case considered, mass savings over 6% are shown to be achievable when utilising variable stiffness laminates as the skin on stiffened panels