Hesam Khaksar

• Doctor of Philosophy
• Researcher at Jagiellonian University

The impact in the nano scale, especially for the softer nanoparticles, is very important. As a result, the effect of different loadings on the contact process of nanoparticles and nanoparticles impact before initiation of contact are studied in this paper. To investigate the nanoparticles impact before contact begins, three theories including Hertz...

In this paper, first, the control the kinematics of ellipsoidal and cubic nanoparticles is developed. Ellipsoidal and cubic contact theories are utilized for dynamics modeling. Moreover, sliding and rolling modes are considered in the substrate. Regarding surface roughness, existing roughness theories are developed from two aspects of geometry and...

Regarding the contact mechanics of smooth nanoparticles, two new geometries, specifically elliptical and cubic are chosen for nanoparticles. The results of elliptical contact simulation show that the JKR theory induces a greater indentation depth in both contact geometries since it includes the adhesion forces. Moreover, the Jamari theory shows a l...

Controlling the motion and its associated parameters is among the most important topics in the field of manipulation and displacement of nanoparticles. Accordingly, this article considers the control of nanomanipulation process in three general areas: 1) the distance between probe and surface, 2) the substrate, and 3) the probe of atomic force micr...

Objective: Shunts are often employed as internal medical devices for draining aberrant fluids from organs. However, depositions of calcification in the shunt walls lead to its failure, requiring frequent replacements. The current surgical procedures for implanting shunts are invasive. Methods: This paper introduces a novel, non-invasive approach...

Non-hydrogenated diamond-like carbon (DLC) films and molybdenum-doped diamond-like carbon (Mo-DLC) films were deposited by direct current magnetron sputtering. The formation was carried out on Si (100) wafers. The influence of molybdenum concentration and deposition temperature on the surface morphology, chemical composition, type of chemical bonds...

The invasive presence of nanoplastics in various ecosystems makes them a significant environmental problem nowadays. One of the main production mechanisms of nanoplastics is mechanical wear. The combination of friction, abrasion, and shear forces can indeed lead to the progressive fragmentation of polymeric materials. The high surface area–volume r...

We have investigated the sliding motion of PMMA microspheres elastically driven on a rippled polyvinyl siloxane surface for different values of normal load, scan velocity, and substrate temperature. The spheres were rubbed both parallel and perpendicular to the ripples, and the resulting friction was found to be almost constant and, respectively, t...

Two series of non-hydrogenated diamond-like carbon (DLC) films and molybdenum doped diamond-like carbon (Mo-DLC) films were grown on the silicon substrate using direct current magnetron sputtering. The influence of molybdenum doping (between 6.3 and 11.9 at.% of Mo), as well as the deposited temperature (between 185 and 235 °C) on the surface morph...

In this chapter, we explore the evolving landscape of microrobotics, categorizing them into tethered, untethered, and collective untethered types, known as microswarms. Particularly focusing on their application in intravascular interventions, such as brain and eye surgeries, we discuss the precision and small size of these robots. The chapter high...

The position control of magnetic medical microrobots is influenced by several environmental uncertainties including the unknown characteristics of the medium and the imaging precision. Furthermore, measuring the physical attributes of the microrobots is a challenging issue. To provide a model-free position control approach for the magnetic medical...

In this chapter we describe two representative applications of atomic force microscopy to investigating early-stage wear on polymeric surfaces and layered materials on the nanoscale. Ripples and exfoliated flakes or chips are the most typical surface structures obtained in each case. On polymers the ripple formation can be interpreted within the Pr...

We demonstrate how doping of non-hydrogenated diamond-like carbon (DLC) films doped with molybdenum (up to 6.2 at.%) can increase the hardness of the DLC surfaces up to 60% and reduce the sliding friction on them up to 25%, as measured on micro/nanometer scales. The films were prepared by DC magnetron sputtering on silicon (100) substrate. AFM, EDX...

Fully soft continuum magnetic (FSCMs) microrobots with highly deformable structures have emerged as a potential solution to robotically controlled endovascular interventions. The microrobot's structure is made of magneto-responsive material, which offers full body control under a magnetic field instead of limited tip deformation. The shape control...

Softness of nanomedicines plays a significant role in antitumor drug delivery and efficiency. Examining and finding optimized contact models to verify and choosing best nanomedicine mechanical properties for each cancer genotype has a profound effect in nano based drug delivery. In this research, appropriate contact models have been identified and...

This paper deals with the development and modeling of cylindrical contact theories and also the simulation of contact forces to be applied in the manipulation of various biological micro/nanoparticles by means of the AFM. First, the simulation of contact forces in four environments has been carried out, which are the most commonly used fluid in bio...

This article investigates the effect of impact on the dynamic modeling and simulation of cubic and elliptic nanoparticles in the manipulation process based on atomic force microscopy (AFM). First, the dynamic equations prior to the motion are presented. Then, according to these equations, two assumptions are considered for nanoparticles motion. Usi...

Four contact models including Hertz, Jamari, Jeng-Wang and Weng-Tang-Zhou-Zhu were considered. To verify the results of contact mechanics, the indentation depth has been compared with spherical geometry. According to the obtained results, by comparing the spherical and elliptical geometries, the indentation depth for spherical geometry is higher th...

In this article, optimum path planning of elliptic and cubic nanoparticles by one and dual probe atomic force microscopes is investigated. Four different parameters are considered in the cost function, including area under critical time–force diagram, critical indentation depth, path smoothness and area under force–time diagram of primary impact of...

Different definitions of nano-technology prove this truth that nano-technology includes wide range of various scientific fields. In fact, nano -technology is an interdisciplinary science and a new approach to the all domains. In Nano manipulation process by utilizing Atomic Force Microscope, contact models play important role for determining critic...

In this article, the collection of studies with regard to the modeling of nanomanipulation based on atomic force microscope (AFM) is discussed. To model the manipulation process, two-dimensional and three-dimensional models in the classical environment and molecular dynamics can be presented. The decisive factor in determining the solution’s type d...

This paper deals with the development and modeling of cylindrical contact theories and also the simulation of contact forces to be applied in the manipulation of various biological micro/nanoparticles by means of the AFM. First, the simulation of contact forces in four environments has been carried out, which are the most commonly used fluid in bio...

The contribution in this paper is to investigate the manipulation of ellipsoidal nanoparticles by atomic force microscopy, taking into consideration of roughness. For the first phase of manipulation, roughness was investigated just for the substrate, but for the second phase, it begins by particle movement substrate and particle roughness is consid...

The aim of this paper is to develop and simulate elastic-perfectly plastic contact theories for proper determination and estimation of contact area in manipulation of micro/nano bioparticles. The nanoparticles studied in this paper are categorized into three different cancerous cell types, lowly (LNCaP) and highly metastatic human prostate cancer c...

Although remarkable attempts have already been made to automate the AFM-based manipulation of biological cells, there are still many ambiguous points regarding the interactions between biological nanoparticles and manipulation tools, especially in different biological environments. As micro/nanoparticles of different shapes are placed in different...

In this paper, elastic-plastic contact theories for soft spherical nanobacteriabased on atomic force microscopy were developed and modeled to be applied in manipulation of various macro/nanobio particles. First, elastic contact was simulated for three types of nanobacteria: S. epidermidis, S. salivarius and S. aureus, using Hertz contact model and...

This article has dealt with the development and modeling of various contact theories for biological nanoparticles shaped as cylinders and circular crowned rollers for application in the manipulation of different biological micro/nanoparticles based on Atomic Force Microscope. First, the effective contact forces were simulated, and their impact on c...