材料期刊网

Preparation of Ultrafine Si Powders from SiH_4 by Laser-induced Gas Phase Reaction

Yali LI , Yong LIANG , Kesheng XIAO , Fen ZHENG and Zhuangqi HU(State Key Laboratory of Rapidly Solidified Nonequlibrium Alloys , Institute of Metal Research , Chinese Academy of Sciences , Shenyang , 110015 , China)

材料科学技术（英文）

High quality ultrafine Si powders have been synthesized from SiH4 by laser induced gas phase reaction. The powders prduced under different synthesis conditions have mean particle size of 10-120nm in diam. with narrow particle size distribution, and free of hard agglomerates.The powders are polycrystalline with the ratio of mean grain to particle diameter being between 0.3-0.7. The size of the powder increases with increasing laser power and reaction pressure,but decreases with increasing silane gas flow rate and the addition of Ar diluent. Grain sizes drop distinctly with the rise of the addition of Ar gas and laser power, but change little with the gas flow rate and reaction temperature. The formation of Si particles under different synthesis conditions is discussed

关键词:

THERMODYNAMIC PROPERTIES OF ALPHA-HELIX PROTEIN - A SOLITON APPROACH - COMMENT

Physical Review E

We disagree with the deduction of the equations of motion for the Davydov soliton and of the results in the paper by Jia-Xin Xiao et al. [Phys. Rev. A 44, 8375 (1991)]. The weakness and faults of the Davydov theory are also indicated.

关键词: davydov solitons;vibron solitons;molecules;excitation;system