چكيده به لاتين
Due to recent developments in nano science, as well as the increasing need for this branch of science in the biological environment, the manipulation of biological cells has been taken into consideration. AFM is a tool for 3D topography and physical properties of the nanoparticle surface. Understanding deformation is important in using atomic force microscopy. The values of this deformation are extracted from the parameters of indentation depth and force from contact mechanics theories. Up to now, the viscoelastic contact modeling of the AFM probe and nanoparticle has not been modeled considering the geometry of the cylinder and crushed cylinder bio particle. On the other hand, selecting the appropriate creep function represents the best description of the viscoelastic behavior of the biological cell. This function represents the cell's behavior, and so far non-linear models have not been presented.
This action will be effective in calculating the manipulation's critical force and time in different motion modes. In this research, in order to upgrade the previous modeling, to provide nonlinear cellular models, suitable viscoelastic contact model for cylindrical and crushed cylindrical geometry, modeling and simulation of three-dimensional manipulation of nanoparticles with this geometry, and finally their motion modes will be study.
Regardless of the biological properties of the cell, the non-linear 2nd order Kelvin, non-linear 3rd order Kelvin, non-linear 2nd order Maxwell and non-linear 3rd order Maxwell mechanical cell models are presented and solved. Creep functions are obtained for each one, and compared with the power law model and experimental data. Then correction coefficients in the models applied. Thereafter, a viscoelastic JKR contact model is proposed for nanoparticles with cylindrical and crushed geometry. Then, by applying cell models in the contact model, the relationships and diagrams of the force-indentation and the radius of contact were obtained.
The non-linear model of the developed non-linear 2nd order Kelvin was taken as the most appropriate cellular model consistent with experimental data, and the simulation and modeling of the first phase of the manipulation was made using it. Subsequently, the selection of the most suitable cellular model (developed non-linear 2nd order Kelvin) and the most comprehensive viscoelastic contact model (viscoelastic JKR model), the first phase of the 3D manipulation was modeled and simulated. Then, three motion modes simulated and critical time and force values are obtained. These modes are the slip of the tip of the probe on the particle, particle's rotation on the surface and the slip of the particle on the surface of the substrate.
