from    
to    
search  

 


清华科学博物馆沙龙第30期:显微镜下的微生物
车辆与运载学院281期学术沙龙-连小珉《老子》系列讲座:何为道
物理系colloquium: 从地球的深处仰望宇宙
转录组、连接组与神经调控
报告题目:
Fabrication and characterization of carbon-based biomorphic composites
 报告人:
Dr. Dickon H. L. Ng
Associate Professor
Department of Physics
The Chinese University of Hong Kong.
报告时间:
2005-11-04 14:30
报告地点:
焊接馆301室
主办单位:
机械系
  简介:

Bioorganic substances like woods or cellulose fibers can be converted into high strength and lightweight carbide-reinforced biomorphic composites. The preparation of these composites involves several steps: (i) transforming natural bioorganic structures to carbon-based bio-templates by drying and pyrolysis, (ii) wetting the carbon bio-templates by infiltration of gaseous or molten metals, or metal-organic solutions, and (iii) converting the wetted bio-templates to functional composites by heat treatment. Biomorphic products, synthesized by this technique, possess bioorganic structures as well as having superior properties of engineering composites of carbides. This presentation describes the synthesis and characterization of biomorphic SiO2/SiC/C and SiC/C composites that contained SiO2 and β-SiC nanostructures. Freshly cut Luk Bamboo (Bambusa Textilis var Fusca) slices were used as our starting material and converted to bio-templates, and the metal-organic tetraethylorhosilicate solution was utilized as a source for Si. In characterizing the products, we found that the tubular structure of bamboo was retained. In addition, micron-sized spheres and nanorods of SiO2 were observed on the walls of the vessels in the samples treated at temperature around 1200oC, while β-SiC nanobelts were found in those samples treated at about 1400oC.

今日相关信息
清华-日立未来先驱IT论坛
科学与危机
Steroid signaling in plants
 
同类别相关信息
Living in an (Advanced) Materials ...
清华论坛第65讲:人类的未来:理智的乐...
The photoproduct systems in trihali...
材料院《材料科学论坛》:Chemical Ima...
液晶与高分子复合材料-清华2017高分子...
学术活动