We construct a theory of the deflection of a bimorph cantilever, applicable to both the isotropic and anisotropic cases, and also including noise effects. The proposed formulation gives the correct expressions for the longitudinal and transverse deflections of a magnetoelastic cantilever for an arbitrary ratio of the thickness of the two components. The optimization of the cantilever as a sensor as a function of the thickness of the two components is discussed and also some results of the cantilever as an actuator are reported.

An effective method of preparation of\ud bismuth nanopowders by thermal decomposition of\ud bismuth dodecyl-mercaptide Bi(SC12H25)3 and preliminary\ud results on their thermoelectric properties are\ud reported. The thermolysis process leads to Bi nanoparticles\ud due to the efficient capping agent effect of\ud the dodecyl-disulfide by-product, which strongly\ud bonds the surface of the Bi clusters, preventing their\ud aggregation and significantly reducing their growth\ud rate. The structure and morphology of the thermolysis\ud products were investigated by differential scanning\ud calorimetry, thermogravimetry, X-ray diffractometry,\ud 1H nuclear magnetic resonance spectroscopy, scanning\ud electron microscopy, and energy dispersive\ud spectroscopy. It has been shown that the prepared\ud Bi nanopowder consists of spherical shape nanoparticles,\ud with the average diameter depending on the\ud thermolysis temperature. The first results on the\ud thermoelectric characterization of the prepared Bi\ud nanopowders reveal a peculiar behavior characterized\ud by a semimetal–semiconductor transition, and a\ud significant increase in the Seebeck coefficient when\ud compared to bulk Bi in the case of the lowest grain\ud size (170 nm)

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A model for the dependence of the electrical conductance, G, with the strain induced by external mechanical stress in conducting particles-polymer composites is presented. The model assumes that the percolation probability between neighboring particles must depart from a scale-invariant behavior but saturate at moderated-high strains, reaching percolation path's saturation, with sigmoid dependence. This dependence is obtained by proposing a dynamic picture where contacts or bonds between neighboring particles are created but also destructed when a stress is applied and relatively moderated or high strains, , are produced in the composite. The electrical conductance of prepared graphite-polydimethylsiloxane composites were measured as function of the applied pressure and fitted by the presented model. The elastic response to the uniaxial compression was studied using a texture analyzer. The possibility of nonuniversal effects in the conduction critical exponent, t, was taken into account. It is concluded that the saturation of the response in the G versus plots cannot be assigned to nonuniversal behavior of the exponent t, or to saturation of the elastic response. On the other hand, the presented model accounts for all the main experimental features observed in these systems and for previously reported data of elastomer composites. The simulated behavior of the piezoresistivity coefficient is also in qualitative agreement with previous reports.