research

I have formulated a shear-lag model for calculating the variation of stress along carbon nanohorns (CNHs), which are conical shaped wrapped carbon sheets, embedded in an epoxy matrix under axial loading.  I found that the stress distribution along the length of CNHs depends on the cone angle of these structures and maximum normal axial stress has a smaller value in CNHs compared to a carbon nanotube (CNT) with same cross-section as of the CNH's tip.  Furthermore, I read an article stating that synthesis of CNHs are easier compared to CNTs.  However, the only article I could f

Forthcoming papers of International Journal of Applied Mechanics (IJAM) Vol.4 No.1:

1.     “A SPECTRAL/HP FINITE ELEMENT FORMULATION FOR VISCOELASTIC BEAMS BASED ON A HIGH-ORDER BEAM THEORY”,  V. P. VALLALA, G. S. PAYETTE AND J. N. REDDY, (TEXAS A&M UNIVERSITY, USA).

Consisting of alternating swelling and nonswelling polymeric layers (SLs and NLs), lamellar gels are 1D photonic crystals with tunable optical properties.  The lamellar structure induces a constraint between the SLs and the NLs, resulting in an anisotropic swelling behavior coupled with deformation.

Dear Colleagues,

we would like to inform you that the Italian Group of Fracture (IGF), engaged in fostering the research in the fields of Fracture Mechanics and Structural Integrity at the national and international levels (IGF is the Italian chapter of the European Structural Integrity Society) has recently setup the following dissemination strategies and activities for 2012:

We report the observation of remarkable electrical self-healing in mechanically damaged ZnO nanobelts. Nanoindentation into intrinsically defect-free ZnO nanobelts induces deformation and crack damage, causing a dramatic electrical signal decrease. Two self-healing regimes in the nanoindented ZnO nanobelts are revealed. The physical mechanism for the observed phenomena is analyzed in terms of the nanoindentation-induced dislocations, the short-range atomic diffusion in nanostructures, and the local heating of the dislocation zone in the electrical measurement. For details, please see