Search results for "corrugation"

Evolution of the sp2 content and revealed multilayer growth of amorphous hydrogenated carbon (a-C:H) films on selected thermoplastic materials

2017

Amorphous hydrogenated carbon (a-C:H) films were gradually deposited on high-density polyethylene (HDPE), polyethylene terephthalate (PET) and polyoxymethylene (POM) via an indirect (f-type) and a direct (r-type) plasma-enhanced chemical vapor deposition (PECVD) process with acetylene plasma. The surface morphologies of the thicker r-depositions on the three different thermoplastics have been analyzed by atomic force microscopy (AFM) at varying micrometer scales. Absorbance spectroscopy has been used to characterize the optical properties of all coatings. Intrinsic stress release phenomena are revealed on thicker layers through the detection of characteristic surface corrugations. Based on …

Dispersive interactions between atoms and nonplanar surfaces

2009

We calculate the dispersive force between a ground state atom and a non planar surface. We present explicit results for a corrugated surface, derived from the scattering approach at first order in the corrugation amplitude. A variety of analytical results are derived in different limiting cases, including the van der Waals and Casimir-Polder regimes. We compute numerically the exact first-order dispersive potential for arbitrary separation distances and corrugation wavelengths, for a Rubidium atom on top of a silicon or gold corrugated surface. We discuss in detail the inadequacy of the proximity force approximation, and present a simple but adequate approximation for computing the potentia…

Numerical simulation of low temperature thermal conductance of corrugated nanofibers

2010

Indagine sperimentale per la valutazione del comfort acustico nelle carrozze ferroviarie

2005

In questo lavoro, reso possibile dall’interesse e dalla disponibilità mostrata concreta-mente dalla Divisione Trasporto Regionale di Trenitalia (Direzione Regionale Sicilia), sono stati approfonditi alcuni aspetti concernenti i fenomeni acustici all’interno dei rotabili fer-roviari, al fine di individuare eventuali legami tra le caratteristiche del sistema costituito dal binomio tracciato-rotabile e le condizioni di comfort acustico dei passeggeri. Una indagine sperimentale di rilevamento delle condizioni acustiche è stata condotta su alcune vetture di convogli operativi su una linea ferroviaria che attraversa il territorio della provincia di Palermo su tracciato misto, urbano ed extraurban…