Gecko and many insects have adopted nanoscale fibrillar structures on their feet as adhesion devices. Here, we consider adhesion between a single fiber and a substrate by van der Waals or electrostatic interactions. For a given contact area A, the theoretical pull-off force of the fiber is sigma(th)A where sigma(th) is the theoretical strength of adhesion. We show that it is possible to design ...

The rupture forces of individual host-guest complexes between beta-cyclodextrin (beta-CD) heptathioether monolayers on Au(111) and several surface-confined guests were measured in aqueous medium by single molecule force spectroscopy using an atomic force microscope. Anilyl, toluidyl, tert-butylphenyl, and adamantylthiols (0.2-1%) were immobilized in mixed monolayers with 2-mercaptoethanol on go...

The rapid growth of web services has already given birth to a set of data dissemination applications. Efficient scheduling techniques are necessary to endow such applications with advanced data processing capability. In this paper we have effectively combined broadcasting of very popular (push) data and dissemination of less popular (pull) data to develop a new hybrid scheduling scheme. The sep...

The adhesion and interaction properties of functionalised surfaces (substrate or cantilever) were investigated by means of atomic force microscope (AFM) related force measurements. The surfaces were functionalised with a polyelectrolyte: Poly(Allylamine Hydrochloride) (PAH), or with silanes: 3 (ethoxydimethylsilyl) propyl amine (APTES) or (3 aminopropyl) triethoxysilane (APDMES). Measurements o...

The adhesion and interaction properties of functionalised surfaces (substrate or cantilever) were investigated by means of atomic force microscope (AFM) related force measurements. The surfaces were functionalised with a polyelectrolyte: Poly(Allylamine Hydrochloride) (PAH), or with silanes: 3 (ethoxydimethylsilyl) propyl amine (APTES) or (3 aminopropyl) triethoxysilane (APDMES). Measurements o...

We study the adhesion between smooth polydimethylsiloxane (PDMS) rubber balls and smooth and rough poly(methyl methacrylate) (PMMA) surfaces, and between smooth silicon nitride balls and smooth PDMS surfaces. From the measured viscoelastic modulus of the PDMS rubber we calculate the viscoelastic contribution to the crack-opening propagation energy γeff(v,T) for a wide range of crack tip velocit...

This paper aims at presenting the effects of short-term sustained load and temperature on time-dependent deformation of carbon fiber-reinforced polymer (CFRP) bonded to concrete and pull-off strength at room temperature after the sustained loading period. The approach involves experimental and numerical analysis. Single-lap shear specimens were used to evaluate temperature and short-term sustai...

We study the mechanics of pull-off of a barnacle adhering to a thin elastic layer which is bonded to a rigid substrate. We address the case of barnacles having acorn shell geometry and hard, calcarious base plates. Pull-off is initiated by the propagation of an interface edge crack between the base plate and the layer. We compute the energy release rate of this crack as it grows along the inter...