tailieunhanh - Báo cáo hóa học: "Multiscale modeling and simulation of nanotube-based torsional oscillators"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Multiscale modeling and simulation of nanotube-based torsional oscillators | Nanoscale Res Lett 2007 2 54-59 DOI S11671-006-9030-8 NANO EXPRESS Multiscale modeling and simulation of nanotube-based torsional oscillators Shaoping Xiao Wenyi Hou Published online 28 November 2006 to the authors 2006 Abstract In this paper we propose the first numerical study of nanotube-based torsional oscillators via developing a new multiscale model. The edge-to-edge technique was employed in this multiscale method to couple the molecular model . nanotubes and the continuum model . the metal paddle. Without losing accuracy the metal paddle was treated as the rigid body in the continuum model. Torsional oscillators containing 10 0 nanotubes were mainly studied. We considered various initial angles of twist to depict linear nonlinear characteristics of torsional oscillators. Furthermore effects of vacancy defects and temperature on mechanisms of nanotube-based torsional oscillators were discussed. Keywords Nanotube Torsional oscillator Multiscale Vacancy defects Temperature Introduction Since the discovery of carbon nanotubes CNTs 1 in 1991 these special cylindrical nanostructures have been intensively studied and discussed. Their extraordinary mechanical and electrical properties 2 ensure that CNTs will play an essential role in the design of nanoscale devices such as nanotweezers 3 nanogears 4 nanotube motors 5 and axial nano-oscillators 6 . Recently a nanoelectromechanical device 7-9 based S. Xiao H W. Hou Department of Mechanical and Industrial Engineering Center for Computer-Aided Design The University of Iowa 3131 Seamans Center Iowa City IA 52242 USA e-mail shaoping-xiao@ on an individual CNT serving as a torsional spring and mechanical support has been successfully fabricated. Williams and co-workers 7 8 reported fabrication of nanoscale mechanical devices which consist of a suspended lever . the paddle connected by CNTs as torsion beams to stationary leads. Papadakis et al. 9 used similar techniques to synthesize so-called .