from    
to    
search  

 


清华大学材料科学与工程研究院《材料科学论坛》学术报告:基于长程电荷序量子效应的新...
高研院神经科学讲座-跨学科科普活动
如何写好一篇科技文章
全球变化科学紫荆论坛第415期:Opportunities for publishing in Nature Sustainab...
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
Catalysis Engineering in University...
清华大学材料科学与工程研究院《材料科学...
清华大学材料科学与工程研究院《材料科学...
清华大学材料科学与工程研究院《材料科学...
双金属协同催化碳碳,碳氧成键
学术活动