Artificial bioactive materials have received increasing attention worldwide in clinical orthopedics to repair bone defects that are caused by trauma, infections or tumors, especially dedicated to the multifunctional composite effect of materials. In this study, a weakly alkaline, biomimetic and osteogenic, three-dimensional composite scaffold (3DS) with hydroxyapatite (HAp) and nano magnesium oxide (MgO) embedded in fiber (F) of silkworm cocoon and silk fibroin (SF) is evaluated comprehensively for its bone repair potential in vivo and in vitro experiments, particularly focusing on the combined effect between HAp and MgO. Magnesium ions (Mg2+) has long been proven to promote bone tissue regeneration, and HAp is provided with osteoconductive properties. Interestingly, the weak alkaline microenvironment from MgO may also be crucial to promote Sprague-Dawley (SD) rat bone mesenchymal stem cells (BMSCs) proliferation, osteogenic differentiation and alkaline phosphatase (ALP) activities. This SF/F/HAp/nano MgO (SFFHM) 3DS with superior biocompatibility and biodegradability has better mechanical properties, BMSCs proliferation ability, osteogenic activity and differentiation potential compared with the scaffolds adding HAp or MgO alone or neither. Similarly, corresponding meaningful results are also demonstrated in a model of distal lateral femoral defect in SD rat. Therefore, we provide a promising 3D composite scaffold for promoting bone regeneration applications in bone tissue engineering.

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For large scale curved composite components cutting process engineering application, high precision and high speed are basic cutting requirements. This paper proposed to improve the working pressures up to 500MPa as high-end water cutting working condition. Mathematical model was established based on lots of complicated tests, and cutting mechanism with the aim of ultra-high pressure water cutting processing center equipment reliability was designed. Through the test application examples, it is showed that high precision and high speed water cutting composite components are corresponding to reliable water cutting processing operation. The theoretical research, structural design, test application of the project in this paper was well adapted to the high technical requirements for composite craft wing processing. It can be seen that it is very important to improve the working pressure to reach high precision and high speed composite components processing under the premise of reliable operation.