Experimental studies were performed using high-fidelity broadband Glaser-NIST conical transducers to quantify stress waves produced by the elastic collision of a tiny ball and a massive plate. These sensors are sensitive to surface-normal displacements down to picometers in amplitude, in a frequency range of 20 kHz to over 1 MHz. Both the collision and the resulting transient elastic waves are ...

Experimental evidence of the photoelectric effect goes back to H. Hertz. It occurred during the famous confirmation experiments of the Maxwellian theory. It is commonly held however that it cannot be explained in the framework of that theory. We are calling attention to some aspects linked with the interpretation of that effect on which, in our opinion, it is worth-

In this study we use a novel approach to quantitatively investigate mechanical and interfacial properties of clonal β-cells using AFM-Single Cell Force Spectroscopy (SCFS). MIN6 cells were incubated for 48 h with 0.5 mM Ca(2+) ± the calcimimetic R568 (1 μM). AFM-SCFS adhesion and indentation experiments were performed by using modified tipless cantilevers. Hertz contact model was applied to ana...

Abstract Existing studies primarily focus on stiffness and damping under full-film lubrication or dry contact conditions. However, most lubricated transmission components operate in the mixed region, indicating that both asperity film exist rubbing surfaces. Herein, a novel method is proposed to evaluate time-varying of spiral bevel gears transient This sufficiently robust for addressing any st...

By integrating eeects of microscopic interactions between statisticaly self-similar fault surfaces, we succeeded in deriving a slip-and time-dependent fault constitutive law that rationally uniies the slip-dependent law and the rate-and state-dependent law (Aochi and Matsu'ura, 199881]). In this con-stitutive law the slip-weakening results from the abrasion of surface asperities that proceeds i...

The geotechnical literature is not exempt from oxymorons. For example, analytical solutions for interparticle contact clearly show that soils and all particulate materials are inherently non-linear -Hertz theoryand non-elastic -Mindlin’s theory (See Richart, Hall and Woods, 1970; Cascante and Santamarina, 1996). Yet, “linearelastic soil behavior” is a common expression. In most cases it refers ...

We consider collisional models for granular particles and analyze the conditions under which the restitution coefficient might be a constant. We show that these conditions are not consistent with known collision laws. From the generalization of the Hertz contact law for viscoelastic particles we obtain the coefficient of normal restitution ǫ as a function of the normal component of the impact v...

Nanoindentation testing of compliant materials has recently attracted substantial attention. However, nanoindentation is not readily applicable to softer materials, as numerous challenges remain to be overcome. One key concern is the significant effect of adhesion between the indenter tip and the sample, leading to larger contact areas and higher contact stiffness for a given applied force rela...

In the present paper, the problem of low-velocity impact of an elastic sphere against a viscoelastic Timoshenko-type beam is studied considering the extension of its middle surface. The viscoelastic features of the beam out of the contact domain are governed by the standard linear solid model with derivatives of integer order, while within the contact domain the fractional derivative standard l...