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In order to explore a set of methods to analyze the structure of Lift-Drag Combined-Type Vertical Axis Wind Turbine (LD-VAWT), a small LD-VAWT was designed according to the corresponding Standards and General Design Requirements for small vertical axis wind turbines. The finite element method was used to calculate and analyze the static mechanical properties and modalities of main parts of a kind of small-scale LD-VAWT. The contours of corresponding stress and displacement were obtained, and first six-order mode vibration profiles of main parts were also obtained. The results show that the main structure parts of LD-VAWT meet the design requirements in the working condition of the rated speed. Furthermore, the resonances of all main parts did not occur during operation in the simulations. The prototype LD-VAWT was made based on the analysis and simulation results in this study and operated steadily. The methods used in this study can be used as a reference for the static mechanical properties and modal analysis of vertical axis wind turbine.

Bismuth molybdate single-crystallites were synthesized by a simple hydrothermal method at different pH values. The as-fabricated samples were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM); it has been found that the pH values of the precursors can significantly influence the structures of the products. Under the Bi/Mo ratio of 2:1 conditions (a nominal composition of Aurivillius structure), low pH leads to the formation of γ-Bi2MoO6 with Aurivillius type structure, while neutral and higher pH values lead to the formation of γ- Bi2MoO6/Bi2O3 composite, and Bi2O3, respectively. The photocatalytic activities of the samples with different structures were measured for the degradation of methylene blue (MB) under simulated sunlight irradiation. Among the as-fabricated bismuth molybdate samples, the γ-Bi2MoO6 exhibited superior photocatalytic efficiency to the γ- Bi2MoO6/Bi2O3 composite and the Bi2O3, mainly due to its unique layered Aurivillius structure, smaller band gap structures and smaller particle sizes. [ABSTRACT FROM AUTHOR]

In this paper, crystalline iron-nickel alloy nanostructures were successfully prepared from two cationic pyridinium derivatives as soft templates in solution. The crystal structure and micrograph of FeNi alloy nanostructures were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and the content was confirmed by energy-dispersive spectrometry. The results indicated that the as-prepared nanostructures showed slightly different diameter ranges with the change of cationic pyridinium derivatives on the surface. The experimental data indicated that the adsorption of cationic pyridinium compounds on the surface of particles reduces the surface charge, leading to an isotropic distribution of the residual surface charges. The magnetic behaviours of as-prepared FeNi alloy nanostructures exhibited disparate behaviours, which could be attributed to their grain sizes and distinctive structures. The present work may give some insight into the synthesis and character of new alloy nanomaterials with special nanostructures using new soft templates. [ABSTRACT FROM AUTHOR]

Bi2MoO6 single-crystallites were synthesized by a simple hydrothermal method in the presence of surfactant sodium dodecyl sulfate (SDS), polyvinyl pyrrolidone (PVP), or cetyl trimethyl ammonium bromide (CTAB). The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and ultraviolet-visible diffuse reflectance spectra (UV-vis DRS) techniques. The photocatalytic activities of the as-fabricated Bi2MoO6 samples were measured for the degradation of methylene blue (MB) under the Xe light illumination. It is shown that the introduction of surfactant have a crucial influence on the size and morphology of the Bi2MoO2 product. Among the as-fabricated Bi2MoO2 samples, the ones derived hydrothermally with CTAB showed outstanding photocatalytic activities for the addressed reaction under simulated sunlight irradiation, attributed to the ultrafine nanocrystals and the higher surface areas. [ABSTRACT FROM AUTHOR]