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Uniform and dense nano-hydroxyapatite (nHA) coating with nanorod-shaped structure was fabricated on carbon nanotubes (CNTs) by combining electrodeposition with biomineralization. The CNTs with nHA coating (nHA–CNTs) were used as reinforcement to improve the mechanical properties of HA. Firstly, a mixed acid solution of nitric acid and sulfuric acid was used to treat CNTs (NS–CNTs). The dispersion of NS–CNTs was obviously improved, and O-containing functional groups were grafted on the surfaces of NS–CNTs by treatment. Then, calcium phosphate (CaP) was deposited on NS–CNTs by electrodeposition, and NS–CNTs were provided with numerous active nucleation sites for the next coating preparation process. Then nanorod-shaped HA crystals were obtained on the surfaces of NS–CNTs by biomineralization. Using the CNTs with nHA coating (nHA–CNTs) as reinforcement, HA-based composites reinforced with CNTs and nHA–CNTs (nHA–CNTs/HA) were fabricated by pressure-less process. Bending strength and fracture toughness of 1.0 wt % nHA–CNTs reinforced HA composites (HAnC1) reaches a maximum (30.77 MPa and 2.59 MPa), which increased by 26.94% and 7.02% compared with 1.0 wt % CNTs reinforced HA composites, respectively. Importantly, the fracture toughness of HAnC1 is within the range of that to compact bone. This work provides theoretical and practical guidance for preparing nHA coating on nanomaterials. It also contributes to the potential application of nHA–CNTs/HA composites for artificial bone implants.

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Abstract. Different with the fact that the traditional imaging optics emphasizes its ability to get clear image on the image plane, the purpose of LED illumination design is to meet the requirement of high availability of optical energy and homogeneity of illumination. As the study object, the LED track lighting has been designed with secondary optical design by the Lighttools design software. After using TIR lens which has two ways of concentrating: reflectors and lenses, the exit light of the spotlight will be adjusted and the illuminated surface will be with high homogeneity. Therefore, it will reduce the harm of the light to human's eyes. In this study, the LED spotlights have been produced and tested with the corresponding test results: Lighting power is 7W, luminous efficiency is82.57lm/W, color rendering index is 83.7, the main wavelength is 488.2nm, the ratio of red, green, blue is 13.1: 83.0: 3.9.