Model nanomechanical

The CNT-polymer interface serves as a model nanomechanical or a lower dimensional system (ID) and physicists are interested in the nature of forces dominating at the nanoscale and the effect of surface forces (which are expected to be significant due to the large surface to volume ratio). 

Depth-sensing nanoindentation is one of the primary tools for nanomechanical mechanical properties measurements. Major advantages to this technique over AFM include (1) simultaneous measurement of force and displacement (2) perpendicular tip-sample approach and (3) well-modeled mechanics for dynamic measurements. Also, the ability to quantitatively infer contact area during force-displacement measurements provides a very useful approach to explore adhesion mechanics and models. Disadvantages relative to AFM include lower force resolution, as well as far lower spatial resolution, both from the larger tip radii employed and a lack of sample positioning and imaging capabilities provided by piezoelectric scanners. 

Fig. 6.7. Nanomechanical model for the converse flexoeffect in an outer hair cell and a schematic of the cell. These cells are cylindrically shaped with lengths ranging from 20 to 90 fxm arranged along the cochlea and with a radius of 4-5 ftm. A hair bundle, composed of stereocilia, is located at the apex of the cell. The lateral wall is the somrce of electromotility and it appears smooth under a light microscope. When examined with electron microscopy, the lateral wall appears corrugated. The folds in the membrane appear to terminate at pillar proteins that extend to the cytoskeleton. The cytoskele-ton is composed of actin filaments cross-linked by spectrin molecules. (Reprinted from Raphael et al. Copyright 2000, with permission from Elsevier.)...

For solid coating layers, a simple analytical model is proposed. It provides general reference values in terms of the strain induced in the coating layer [11,12]. It will help toward analyzing the static behavior of cantilever sensors and various nanomechanical sensors in conjunction with physical properties of coating films as well as optimizing the films for higher sensitivity. The details of the analytical model will be discussed later. 

According to a recent study [11], deflection (signal intensity) of a nanomechanical sensor strongly depends on the thickness of a receptor layer. In this section, we focus on the analytical model that describes the relationship between deflection of a cantilever and various physical parameters of a cantilever itself and receptor layer on it. This analysis provides a practical guideline to optimize the thickness of a receptor layer. 

Vakhrushev A. V., Fedotov A. Yu., Vakhrushev A.A. Modeling of processes of composite nanoparticle formation by the molecular dynamics technique. Part 1. Structure of composite nanoparticles. Nanomechanics Science and Technology. An International Journal, DOI 10.1615/NanomechanicsSciTechnoUntJ.v2.il.20, vol. 2, issue 1, pp. 9-38,2011. 

Vakhrouchev A. V, Severyukhin A. V, Severyukhina O. Y. Modeling the initial stage of formation of nanowhiskers on an activated substrate. Part 2. Numerical investigation of the structure and properties of au-si nanowhiskers on a sihcon substrate. Nanomechanics Science and Technology An International Journal, vol. 3, issue 3, pp. 211-237,2012. 

Yerramshetty, J.S., Lind, C., and Akkus, O. (2006) The compositional and physicochemical homogeneity of male femoral cortex increases after the sixth decade. Bone, 39 (6), 1236-1243. Donnelly, E. et al. (2010) Effects of tissue age on bone tissue material composition and nanomechanical properties in the rat cortex. J. Biomed. Mater. Res. A, 92 (3), 1048-1056. Donnelly, E. et al (2010) Contribution of mineral to bone structural behavior and tissue mechanical properties. Calcif. Tissue Int., 87 (5), 450—460. Pathak, S. et al (2012) Assessment of lamellar level properties in mouse bone utilizing a novel spherical nanoindentation data analysis method. J. Mech. Behav. Biomed. Mater., 13, 102—117. Burket, J.C. et al (2013) Variations in nanomechanical properties and tissue composition within trabeculae from an ovine model of osteoporosis and treatment. Bone, 52 (1), 326-336. Carden, A. et al (2003) Ultrastructural changes accompanying the mechanical deformation of bone tissue a Raman imaging study. Calcif. Tissue Int., 72 (2), 166-175. 

D axisymmetric FEM models that can reduce computational time [59]. The multiscale RVE integrates nanomechanics and continuum mechanics, bridging the length scales from nanoscale to mesoscale. 

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