Browsing by Author "Rathore, Jitendra S."

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Atomistic modeling and dynamic analysis of boron nitride nanotube in the presence of hexagonal defect
(Elsevier, 2020) Rathore, Jitendra S.; Srivastava, Sharad
The feasibility of defective Single-Walled Boron Nitride Nanotube (SW-BNNT) has been explored in the present paper employing finite element based three-dimensional atomistic modeling approach. The effect of missing of three conjugate Bsingle bondN pairs in SW-BNNT resulting in formation of hexagonal defect in SW-BNNT on resonance frequency has been analyzed in the present paper. Two different types of SW-BNNT i.e., armchair (5, 5) and Zigzag (5, 0) BNNT of 5 nm length have been analyzed for cantilever and bridged configuration. Further, present work explores the effect of position of defect on resonance frequency in SW-BNNT. The simulation results revels that resonance frequency decreases due to presence of defect and this reduction in frequency increases if the position of defect moves towards free end in the case of cantilever configuration. On the contrary for bridge configuration the resonance frequency decreases continuously if position of defect moves from fixed end to midpoint. Thus it can be concluded that due to presence of defect in nanotube, the resonance frequency decreases and suggests that stiffness is more dominating than mass of nanotube.
A brief manifestation of anti-bacterial nanofiller reinforced coatings against the microbial growth based novel engineering problems
(Elsevier, 2021) Rathore, Jitendra S.; Belgamwar, Sachin U.
An anti-bacterial material coating can help to break the spread of bacteria and viruses via metallic surfaces of biomedical devices, communication devices, food packages, research laboratories and public infrastructures like shopping malls, transports, toilets, etc. In addition, anti-bacterial material coatings owing to adequate tribomechanical and anti-corrosion properties can also help to resolve a major engineering problem of biofouling on marine installations and watercrafts’ surfaces. In recent times, the use of anti-bacterial nanocomposites coatings is emerging rapidly for various engineering applications. Here, metal matrix nanocomposites (MMNCs) are acquiring a significant role in the upcoming field of anti-bacterial material applications owing to high tribo-mechanical and anti-corrosion properties. The bio-responsive mechanism of MMNC coatings to perform anti-bacterial activities can protect the surfaces in biological environments. The nanofillers in the metal matrix plays a key role during anti-bacterial activities to kill the microbials. The composition of nanofillers can be inorganic, organic and hybrid, including advance nano tropes (i.e., allotropes of carbon and BNNT), which can be reinforced in metal matrix. This review study is addressing a problem of bacterial colonization on the surfaces that causing microbial growth based novel engineering problems and suggesting a facile and low-cost solution through an anti-bacterial MMNC coating.
Co-deposited CuNi@MWCNTs nanocomposites for structural applications: tribo-mechanical and anti-corrosion performances
(Taylor & Francis, 2022-10) Rathore, Jitendra S.
In the present work, multi-walled carbon nanotube (MWCNT) nanofiller reinforced copper-nickel alloy (CuNi@MWCNTs) nanocomposites were synthesised by a modified electro-chemical co-deposition followed by compaction and sintering. During this method, CuNi@MWCNTs were co-deposited on a cathode tip at room temperature and collected from the electro-chemical bath in powdered form. Subsequently, the powdered nanocomposites were dried, compacted and sintered to prepare solid pellets. The influence of different amounts (25, 50 and 100 mg L−1) of MWCNT nanofillers in the deposition bath on microstructure, mechanical and anti-corrosion properties of CuNi@MWCNTs nanocomposites was investigated. The microhardness, compressive yield strength and friction coefficient of CuNi@MWCNTs (100 mg L−1) nanocomposites were enhanced by 45.7%, 37.2% and 55.1%, respectively, compared to that of pure CuNi alloy. In addition, the CuNi@MWCNTs nanocomposites obtained also exhibited improved anti-corrosion property in 3.5 wt.% NaCl solution at continuous agitation of 150 rpm and 27°C temperature. Based on the research outcomes, this approach for synthesising CuNi@MWCNTs nanocomposites may be proposed for scale-up industrial trials.
Co-deposited Zn-Cu/Gr nanocomposite: Corrosion behaviour and in-vitro cytotoxicity assessment
(Taylor & Francis, 2021-04) Belgamwar, Sachin U.; Rathore, Jitendra S.
Zn-Cu alloys have been considered as potential candidates for bioimplant applications due to their moderate corrosion rate and admirable mechanical properties with non-toxic nature to the human body. However, with the incorporation of advanced reinforcements, such as carbon allotropes, the properties and applicability of a Zn-Cu alloy matrix can be further enhanced. In this research, graphene (Gr) nanoplatelets reinforced Zn-Cu/Gr nanocomposites were synthesised through a modified electro-codeposition method with different concentrations of Gr (25, 50 and 100 mg L−1) in the electrolyte bath. The prepared powder samples were compacted and sintered to form pellets. The pellets were tested for mechanical and in-vitro corrosion. The obtained micro-hardness, compressive yield strength (CYS) and ultimate compressive strength (UCS) of Zn-Cu/Gr (100 mg L−1) nanocomposite are 151 HV, 340 MPs and 362 MPa with increments of 84.1%, 118% and 70.7% compared to pure Zn-Cu alloy, respectively. The reduced wear rates and friction coefficients of Zn-Cu/Gr nanocomposites are attributed to crystallite size refinement and Gr content. The electrochemical corrosion rate is reduced by 66.6% from 33 × 10−3 mm year−1 for pure Zn-Cu alloy to 11 × 10−3 mm year−1 for Zn-Cu/Gr (100 mg L−1) nanocomposites, owing to Gr barrier protection. The in-vitro cytotoxicity assessment reveals that the prepared Zn-Cu/Gr nanocomposite is non-toxic for Gr concentration up to 50 mg L−1 in the electrolyte bath. The results show that a non-toxic Zn-Cu/Gr nanocomposite with outstanding tribo-mechanical and anti-corrosion properties can be synthesised by the proposed method.
Comparison of Piezo-material based Energy Transduction Systems for Artificial Nanoswimmer
(IOP, 2018) Rathore, Jitendra S.
The energy harnessing is a process of obtaining energy from the surrounding environment and converting into electrical energy. In the last two decades, there has been a plenteous study in energy harnessing. Now a day, energy harnessing using piezoelectric materials has drawn attention of researchers due to low cost, flexibility and light weight. The benefits of piezoelectric material can be utilized by designing a self-powered device for artificial nanoswimmer. Some of the ceramics which displays the piezoelectric effect are lead-zirconate-titanate (PZT), lead-titanate (PbTiO2), lead-zirconate (PbZrO3) and Barium Titanate (BaTiO3). PZT is most extensively used piezoelectric material in the field of energy harnessing but it is brittle in nature. Lead based piezoelectric materials are toxic in nature and may not suitable for in-vivo biomedical applications. To eradicate this problem, researchers are interested in synthesizing lead free piezoelectric material such as Aluminium Nitride (AIN), Barium Titanate (BaTiO3) and Polyvinylidenefluoride (PVDF). The biocompatibility of PVDF makes it appropriate to be used for energy harnessing in human body for applications like on board powering of nanoswimmer for various disease detection and drug delivery. In this paper, a cantilever beam is being simulated in COMSOL to study electric potential generated on the surface of beam made of different piezoelectric materials such as AIN, PVDF and PZT due to fluidic pressure, which will be utilized as energy for actuation of artificial nanoswimmer. Piezo-based cantilever beams have been compared and maximum electric potential is being observed in PVDF based beam. PVDF seems most promising piezoelectric material for in-vivo biomedical application and it is readily available.
Cupronickel composites: An overview of recent progress and applications
(CRC Press, 2023) Rathore, Jitendra S.; Belgamwar, Sachin U.
This study presents an overview of the various types of composites and their fabrication methods. The study then presents a summary discussion on the fabrication of various cupronickel composites using electrodeposition method and powder metallurgy method. Cupronickel composites are fabricated by adding reinforcing material into the cupronickel alloy matrix, which has led to a significant interest due to their superior hardness, wear resistance, tensile strength, macrofouling resistance, corrosion resistance anti-bacterial properties. Due to these properties, cupronickel composites are employed in various engineering applications such as condenser tubes, cooling circuits, heat exchangers, microelectronics, and condensers. Based on the critical assessment of the literature, existing challenges with possible solutions and future research opportunities were discussed.
Design and analysis of helical flagella propelled nanorobots
(IEEE, 2009) Rathore, Jitendra S.
Advancement in the field of nanorobotics has been facilitated by the current advances in nano-bio-technology and nanofabrication methods. The important uses of nanorobots are in advancing medical technology, healthcare and environment monitoring. In bio-medical applications, nanorobots need to swim in biological fluids flowing in narrow channels of few hundred nanometer size. The dominating effects in nanometer size domains are increased apparent viscosity and which makes the design of a propulsion mechanism a challenging task. Micro and nano size biological organisms move by generating planar waves or rotating helical flagella. In the present work, design of propulsion with helical flagella is proposed and a generalized analytical model is developed, simulated and discussed. The performance parameters of the developed model viz. velocity and efficiency have been computed based on resistive force theory and compared with those of the model available in literature. Improved performance, feasibility and generality of the developed flagellar model have been discussed.
Development and characterization of Cu-Gr composite coatings by electro-co-deposition technique
(Elsevier, 2020) Rathore, Jitendra S.; Belgamwar, Sachin U.
Graphene nanoplatelets (Gr) are considered as promising reinforcing elements in the composite coatings owing to its exceptional mechanical, electrochemical, electrical, and thermal properties. In the present work, Cu-Gr composite coatings were deposited on stainless steel substrate from the electrolyte bath containing different concentrations of Gr using the electro-co-deposition technique. The microstructure and phases of the Cu-Gr composite coating were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy dispersive x-ray spectroscopy (EDS). Microhardness tester was employed to calculate the microhardness. The experimental results show that the surface morphology and microstructure of the Cu-Gr composite coatings are significantly affected by the reinforcement of Gr. The microhardness of the Cu-Gr (0.2 g/L) composite coating is enhanced by 21.42% compared to the pure Cu coating.
Dynamic analysis of boron nitride nanotube using different boundary conditions under influence of vacancy defect: Insights from finite element method
(Elsevier, 2023-02) Rathore, Jitendra S.
In this paper, the effect of defects such as atomic vacancies (single atom vacancies like boron atom(Vb) or nitrogen atom vacancy(Vn) and di-atomic vacancies(VB-N) corresponds to vacancy of one boron and adjacent one nitrogen atom) on the vibrational behaviour of a single-walled boron nitride nanotube (SWBNNT) are investigated using finite element modelling in context of their applicability as mass sensors. The change in resonance frequency produced by vacancy defects at various points throughout the span when a mass is connected to the tip has also been examined. Space frames with three-dimensional components and point masses have been used to explain the cantilevered armchair (5, 5) and zigzag (10, 0) SW-BNNT with changing vacancy defects. The position of atomic vacancy has been varied (i.e., at 25 %, 50 % and 90 % of length from fixed end) to investigate the effect of location of defect along the length on the resonance behaviour of SW-BNNT. Further defective BNNTs have been analysed in such a way that the same can be used as nanomechanical resonator for detecting small mass of the order of femtogram level. For this,a small mass (varying from 10-20 to 10−25kg) is attached at the tip of cantilevered SW-BNNT. Substantial drop in frequency shift is observed when the position of defect moves toward the free end. the excitation frequency of defective BNNT is larger near the free end as compared to pristine one.
Effect of current on the characteristics of CuNi-G nanocomposite coatings developed by DC, PC and PRC electrodeposition
(Springer, 2021-08) Rathore, Jitendra S.; Belgamwar, Sachin U.
Copper–nickel (CuNi) and graphene nanoplatelet-reinforced CuNi (CuNi-G) nanocomposite coatings were prepared on the surface of stainless-steel substrates in a citrate bath using direct current (DC), pulse current (PC), and pulse reverse current (PRC) electrodeposition techniques. The effect of various electrodeposition currents on the morphology, composition, contact angle, microstructure, microhardness, and wear performance of the coatings were studied. Substantial changes in the surface morphology and microstructure of CuNi-G nanocomposite coatings were observed. The results show that the incorporation of G significantly enhanced the microhardness and wear resistance of electrodeposited coatings. PC and PRC electrodeposited CuNi-G nanocomposite coatings show higher microhardness and wear resistance than DC electrodeposited coatings because of smaller crystallite size, higher content of G, and lower surface roughness.
Effect of Graphene Nanoplatelets Addition on the Mechanical, Tribological and Corrosion Properties of Cu–Ni/Gr Nanocomposite Coatings by Electro-co-deposition Method
(Springer, 2019-09) Rathore, Jitendra S.; Belgamwar, Sachin U.
Nowadays, corrosion of metals is a major problem faced by marine, chemical and automobile industries. Therefore, several researchers are taking efforts to develop composite coatings reinforced with nanoscale materials for high corrosion resistance. In the present work, graphene nanoplatelets (Gr) are incorporated with Cu–Ni matrix to fabricate Cu–Ni/Gr nanocomposite coatings by electro-co-deposition method. Also, the influence of the various concentrations of graphene nanoplatelets in the plating bath on the surface morphology, elemental composition, microstructure, crystallite size, lattice strain, microhardness, average friction coefficient, wear loss and corrosion resistance of these coatings have been studied. The study shows that the mechanical, tribological and corrosion properties of the coatings are enhanced with graphene nanoplatelets incorporation in Cu–Ni matrix. The measured microhardness for Cu–Ni/Gr (400 mg/L) nanocomposite coating increases by 44.17% compared to pure Cu–Ni coating. Also, immersion study indicates that the incorporation of graphene nanoplatelets stabilizes the corrosion potential and enhances the corrosion resistance.
Efficacy of ANN and ANFIS as an AI Technique for the Prediction of COF at Finger Pad Interface in Manipulative Tasks
(Springer, 2023-03) Rathore, Jitendra S.; Srivastava, Sharad
Current work intends to compare the modelling ability of two popular artificial intelligence (AI) techniques, namely artificial neural network (ANN) and adaptive-neuro fuzzy inference system (ANFIS). Outcome of study is useful in prediction and further optimization of the coefficient of friction in the design of assistive devices for an ergonomics and comfort of the user. Experiments were conducted using Taguchi L16 design of experiments (DOE). Total of 16 experimental runs were conducted. Two extrinsic factors normal load (2, 4,6, & 8 N) and sliding velocity (4, 6, 8 & 10 cm/s) that affect the finger pad friction are taken as input variables, while coefficient of friction (COF) between finger pad and the stainless steel (SS) probe is the output variable. ANN with 2 inputs, 10 hidden, and 1 output layer is trained by three algorithms, viz. Levenberg–Marquardt (R2 = 0.96), Bayesian Regularization (R2 = 0.93), and Scaled Conjugate Gradient (R2 = 0.98) based on the correlation coefficient. Although, both the techniques highlight significant predictability and accuracy, ANFIS results shows overfitting of the data. Hence, ANN technique is relatively better than ANFIS.
Electro-codeposited γ-Zn-Ni/Gr composite coatings: Effect of graphene concentrations in the electrolyte bath on tribo-mechanical, anti-corrosion and anti-bacterial properties
(Taylor & Francis, 2021-10) Jha, Prabhat Nath; Rathore, Jitendra S.; Belgamwar, Sachin U.
In this paper, low-cost and industrially scalable γ-Zn-Ni/Gr composite coatings were electro-codeposited from an acid-sulphate based electrolyte bath. The microstructure, morphology, composition, microhardness, wear performance, corrosion resistance and anti-bacterial properties of the composite coatings were investigated in detail and compared with a Zn-Ni alloy coating. The XRD diffraction peaks of prepared coatings confirm the presence of the γ phase of the Zn-Ni alloy. Results suggested that the addition of Gr effectively reduced the crystallite size and altered the morphology. As a result, the microhardness, wear performance and corrosion resistance were improved significantly. The γ-Zn-Ni/Gr composite coating prepared with 100 mg L−1 of Gr addition in the electrolyte bath displayed the highest microhardness of 243 HV and the lowest coefficient of friction of 0.32. The anti-bacterial activity tests confirmed that the γ-Zn-Ni/Gr composite coating (from the 100 mg L−1 bath) has the highest anti-bacterial activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus).
Electro-codeposition and properties of Cu–Ni-MWCNTs composite coatings
(Taylor & Francis, 2021-02) Belgamwar, Sachin U.; Rathore, Jitendra S.
In this work, multi-walled carbon nanotubes reinforced Cu–Ni matrix (Cu–Ni-MWCNTs) composite coatings were produced using the electro-codeposition method by adding different concentrations of MWCNTs (0.05, 0.1 and 0.15 g L−1) to the Cu–Ni plating bath. To achieve effective dispersion of the MWCNTs, the plating solution was stirred using an ultrasonicator (20 kHz and 500 W) for 120 min. Cu–Ni-MWCNTs composite coatings were characterised by scanning electron microscopy and X-ray diffraction to study the surface morphology and microstructure of the coatings. In addition, the effects of MWCNTs on the microhardness, wear resistance and electrical conductivity of the coating were investigated by microhardness tester, pin on disk wear tester and four-point probe system respectively. All Cu–Ni-MWCNTs composite coatings showed enhanced microhardness and wear performance as compared to the Cu–Ni coating. The Cu–Ni-MWCNT (0.15 g L−1) composite coating exhibited maximum microhardness of 438 HV and minimum wear loss of 0.9 mg among all the coatings, in the same pin-on-disk test conditions, which is attributed to the combined effect of microstructural refinement, higher content of MWCNTs and superior properties of MWCNTs. Electrical studies reveal that MWCNTs play a vital role in increasing electrical conductivity by 1.21 times of magnitude.
Engineering Nanorobots: Chronology of Modeling Flagellar Propulsion
(ASME, 2010-06) Rathore, Jitendra S.
Nanorobots are propitious to swim or fly compared with crawling and walking because of issues with desirable characteristics of high velocity, efficiency, specificity, controllability, and a simple propagation mechanism that can be realized with miniaturized parts. Inspired by the fact that microorganisms existing in nature function expeditiously under these circumstances, researchers have shown a great interest to conceptualize, model, analyze, and make micro-/nanosized swimmers (nanorobots) that can move in body fluids for applications such as targeted drug delivery, nanomedication, and in-viscera nanosurgery. The present work compiles modeling of physics as investigated since 1951 of flagellar propulsion in engineering nanorobots. Existing theories in flagellar propulsion such as resistive force theory, slender body theory, Kirchhoff rod theory, bead model, and boundary element method as well as progress in designing the propulsion system of a nanorobot are summarized, and various interdisciplinary aspects of realizing nanorobots and issues in moving nanorobots have been presented chronologically.
An evaluation of tactile frictional behavior of the wooden material
(IOP, 2019) Rathore, Jitendra S.; Shrivastava, Sharad
Skin tribology and contact mechanics have emerged as a recent topic of research, intended to unveil the behavior of human skin. There have been variegated efforts to calculate the coefficient of friction with respect to various parameters such as sliding speed, normal load, and surface roughness. Wood and other timber products have their importance considering the ergonomically designs that have gained importance nowadays. This article shows the relation between normal load, average sliding speed and coefficient of friction (μ) of various types of woods (Rosewood, Sunmica, Teak wood and Pine wood). An experimental investigation is conducted to understand frictional behavior between human skin and different types of woods. Wooden material has been tested with the normal load having the range of 6.5N to 13N. The variation of μ has been remarked as μrosewood>μpine>μteak>μsunmica. Experimental observation shows that the rosewood has the highest COF which suggests its application where grip and strength of high order are required.With decreasing sliding speed, the relation between normal load and μ become more significant.
Experimental investigation of biomimetic propulsion through a scaled up branched flagellated artificial nanoswimmer
(Taylor & Francis, 2020-05) Rathore, Jitendra S.
Locomotion of bacteria in fluid at small scale is accomplished by cilia and flagella present on its surface. In the present study, existence of cilia on Paramecium surface is mimicked to design scaled-up swimmer rather than utilising its biological function. In the present study, the branches (cilia) on flagella (Paramecium) is employed for designing of tail of an artificial nanoswimmer and experiments are performed at scaled-up level in silicon oil medium to maintain low Reynolds number. The effects of branches on generation of thrust force are investigated by fabricating the branched flagella using flexible polydimethylsiloxane biocompatible material suitable for human body and biological applications. The resulting data are quantitatively compared through statistical analysis. In the present research work, various designs of branched flagellated swimmer are fabricated by varying the number of branches and spacing between branches. Enhancement in thrust force is observed approximately 24% when number of branches is increased from 8 to 28. Therefore, it is concluded that branches on flagella play significant role in enhancement of thrust force for propelling nanoswimmer. Spacing between 8 branches flagella is also varied from 5 to 15 mm and percentage increase in thrust force is observed as 8.1%.
Experimental study on helical propulsion system of artificial nanoswimmer: Low reynolds number
(IEEE, 2017) Rathore, Jitendra S.
Development in the field of nanotechnology makes possible the production of nanorobots and its usage inside the human body for various biomedical applications. Introducing a nanorobot inside a human body faces various challenges. One of the major challenges is its propulsion mechanism. Since the flow regime is of low Reynolds number, normal propulsion systems would find itself impossible to produce net forward thrust in such media. A rigid helix is found to produce thrust force and is a perfect place to start with in low Reynolds number propulsion. In this paper, a set of helical flagella has been fabricated in macro domain and the effect of change of wavelength, wire diameter and helix diameter is investigated on the thrust force produced by rigid helical filament using Resistive Force Theory.
Facile and Scalable Co-deposition of Anti-bacterial Zn-GNS Nanocomposite Coatings for Hospital Facilities: Tribo-Mechanical and Anti-corrosion Properties
(Springer, 2021-10) Rathore, Jitendra S.; Jha, Prabhat Nath; Belgamwar, Sachin U.
Frequently touched surfaces in the hospital environment act as a reservoir for the bacteria responsible for healthcare-associated infections (HCAIs). In this study, graphene nanosheets (GNS) were incorporated into a low-cost Zn coating using electrochemical co-deposition (ECD) to prevent HCAIs. The effects of different concentrations of GNS in the ECD bath (25 mg/L, 50 mg/L and 100 mg/L) were evaluated in detail for microstructural, tribo-mechanical, surface wetting, anti-corrosion, and anti-bacterial features of coatings. The microhardness, friction coefficient, wear loss, and polarization resistance values were remarkably improved from 77 HV, 0.7 mg, 26.1 mg and 13.68 kΩ cm2 mg for the pure Zn coating to 151 HV, 0.48 mg, 12.09 mg and 2.3 kΩ cm2 for the Zn-GNS (100 mg/L) nanocomposite coating, respectively. The anti-bacterial activities of the coatings were enhanced with the increase in GNS concertation in the ECD bath and Zn-GNS (100 mg/L) nanocomposite coating exhibited inhibition zones of 22 mm and 25 mm against Staphylococcus aureus and Escherichia coli bacteria.
Facile synthesis of graphene by ultrasonic-assisted electrochemical exfoliation of graphite
(Elsevier, 2021) Belgamwar, Sachin U.; Rathore, Jitendra S.
Graphene, a 2-dimensional form of carbon, attracted significant attention in a wide range of applications such as energy storage, power generation, chemical sensors, composite materials owing to its unmatched physical and chemical properties. In this study, graphene powder was synthesized by ultrasonic-assisted electrochemical exfoliation of the graphite electrode from acidic bath. An external ultrasonic bath (ultrasonic frequency of 40 kHz and ultrasonic power of 180 W) was employed to provide ultrasonic assistance during the electrochemical exfoliation process. The synthesized graphene powder was characterized with FTIR spectroscopy, Raman spectroscopy, XRD, and SEM techniques to study the chemical, microstructural and morphological properties. FTIR spectrum exhibited the C–O and O–H functional groups and the C=C stretching of the hexagonal ring of graphene. Raman spectrum showed two sharp peaks for ID and IG bands at ∼1350 cm−1 and ∼1580 cm−1, respectively. The XRD results revealed the polycrystalline nature of graphene powder. The SEM results showed various sizes and shapes of graphene powder. Our proposed method shows huge potentials for facile synthesis of graphene powder on a large scale.