نتایج جستجو برای: Triple-Walled Shell

تعداد نتایج: 113980  

Journal: :journal of structural engineering and geo-techniques 2012
armin a.nobakhtnamin

this study aimed to investigate the effects of stiffeners on buckling of thin cylindrical shells under uniform axial compression. to this end, more than 300 finite element models of stiffened cylindrical shells were prepared. the variables considered are shell thickness, number, dimension and the location of the vertical and horizontal stiffeners as well as circular symmetrical imperfections. r...

In this paper, an elastic shell model is presented for postbuckling prediction of a long thinwalledcylindrical shell under axial compression. The Ritz method is applied to solve the governingequilibrium equation of a cylindrical shell model based on the von-Karman type nonlinear differentialequations. The postbuckling equilibrium path is obtained using the energy method for a long thin-walledcy...

Journal: :Physical review letters 2007
J Y Huang S Chen Z F Ren Z Wang K Kempa M J Naughton G Chen M S Dresselhaus

We report exceptional ductile behavior in individual double-walled and triple-walled carbon nanotubes at temperatures above 2000 degrees C, with tensile elongation of 190% and diameter reduction of 90%, during in situ tensile-loading experiments conducted inside a high-resolution transmission electron microscope. Concurrent atomic-scale microstructure observations reveal that the superelongatio...

Journal: :Nanotechnology 2008
C Y Wang L C Zhang

This paper proposes a two-dimensional elastic shell model to characterize the deformation of single-walled carbon nanotubes using the in-plane rigidity, Poisson ratio, bending rigidity and off-plane torsion rigidity as independent elastic constants. It was found that the off-plane torsion rigidity of a single-walled carbon nanotube is not zero due to the off-plane change in the π-orbital electr...

Journal: :MATEC Web of Conferences 2019

Journal: :international journal of nanoscience and nanotechnology 2011
s. basir jafari r. malekfar s. e. khadem

in this paper, the radial breathing mode (rbm) frequencies of multi-walled carbon nanotubes (mwcnts) are  obtained based on the multiple-elastic thin shell model. for this purpose, mwcnt is considered as a multiple concentric elastic thin cylindrical shells, which are coupled through van der waals (vdw) forces between two adjacent tubes. lennard-jones potential is used to calculate the vdw forc...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2005
Byung Hee Hong Joshua P Small Meninder S Purewal Asher Mullokandov Matthew Y Sfeir Feng Wang Ju Young Lee Tony F Heinz Louis E Brus Philip Kim Kwang S Kim

We report a simple but powerful method for engineering multi-walled carbon nanotubes (MWNTs) by using manipulation by an atomic-force microscope. The successive shell-by-shell extraction process of ultralong MWNTs allows the exposure of the innermost single-walled carbon nanotubes (SWNTs), which have diameters as small as approximately 0.4 nm. The inner-shell extraction process changes the elec...

2012
Weien Yuan Zhenguo Liu

In order to address preserved protein bioactivities and protein sustained-release problems, a method for preparing double-walled microspheres with a core (protein-loaded nanoparticles with a polymer-suspended granule system-formed core) and a second shell (a polymer-formed shell) for controlled drug release and preserved protein bioactivities has been developed using (solid-in-oil phase-in-hydr...

2010
Jun Ha Lee Oh Kuen Kwon Ho Jung Hwang Jeong Won Kang

We introduce intertube interactions of a cantilevered triple-walled carbon-nanotube (TWCNT) resonators via classical molecular dynamics simulations. The fundamental frequencies of TWCNT resonators were less than those of singleand double-walled carbon nanotubes of a given diameter because of the increasing intertube disturbance. Our results imply that for a nanotube with a given diameter, the f...

Journal: :international journal of nano dimension 0
r. ansari department of mechanical engineering, university of guilan, p.o. box 3756, rasht, iran h. rouhi department of mechanical engineering, university of guilan, p.o. box 3756, rasht, iran

in this paper, the stability characteristics of single-walled carbon nanotubes (swcnts) under the action of axial load are investigated. to this end, a nonlocal flügge shell model is developed to accommodate the small length scale effects. the analytical rayleigh-ritz method with beam functions is applied to the variational statement derived from the flügge-type buckling equations. molecular dy...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید