Finite element stiffness and consistent mass matrices are derived for helically wound, symmetrical composite tubes. The tubular element is considered to have constant cross-section and small deformations restricted to a plane. Each node has three degrees of freedom: axial and transverse displacement and rotation (slope of transverse displacement). Shell theory and lamination theory are used to ...

Structural health monitoring (SHM) is important for reducing maintenance costs while increasing safety and reliability. Traditionally, structural integrity tests required attachment of sensors to the material surface. This is often a burdensome and time-consuming task, especially considering the size and magnitude of the surfaces measured (such as aircraft, bridges, structural supports, etc.). ...

Lithium aluminum hydride (LiAlH4) is an interesting high capacity hydrogen storage material with fast hydrogen release kinetics when mechanically activated with additives. Herein, we report on a novel approach to produce nanoscale LiAlH4 via a bottom-up synthesis. Upon further coating of these nanoparticles with Ti, the composite nanomaterial was found to decompose at 120 ◦C in one single and e...

The present study aims at developing A356/Al2O3(np) nano-composite with a novel and cost effective method for attaining homogeneous dispersion of Al2O3 nanoparticles in the Al matrix. In the current research, Al micro powders distributed on aluminum foil and then Al2O3 nanoparticles ultra-sounded in ethanol and sprayed on Al substrate. Subsequently, the sandwich foil was added to molten A356 du...

The KLOE experiment has collected 2.4 pb of integrated luminosity during the commissioning of the DAΦNE φ-factory in 1999. The performance of the detector has been studied using the φ → KLKS decays collected during this period, yielding also first measurements of relevant K parameters such as masses and lifetimes. A clean KS → π π sample is used to select KL → ππ CP-violating decays and KL → KS...

OBJECTIVE The study aimed to evaluate effects of air abrasion with alumina or glass beads on bond strengths of resin cements to CAD/CAM composite materials. MATERIAL AND METHODS CAD/CAM composite block materials [Cerasmart (CS) and Block HC (BHC)] were pretreated as follows: (a) no treatment (None), (b) application of a ceramic primer (CP), (c) alumina-blasting at 0.2 MPa (AB), (d) AB followe...

The propagation of elastic waves along composite wire rope is considered. The rope is modeled as co-axial layers of cylindrically anisotropic material. Simple kinematical assumptions lead to a ‘‘rod theory’’ for the wire rope, consisting of three coupled onedimensional wave equations. Solutions of these equations are found. Results for a particular aluminum conductor steel reinforced (ACSR) con...