Ultrasonic waves in a single walled armchair carbon nanotube resting on nonlinear foundation subjected to thermal and in plane magnetic fields

Selvamani, Rajendran,Jayan, M. Mahaveer Sree,Ebrahimi, Farzad Techno-Press 2021 Coupled systems mechanics Vol.10 No.1

The present paper is concerned with the study of nonlinear ultrasonic waves in a magneto thermo (MT) elastic armchair single-walled carbon nanotube (ASWCNT) resting on polymer matrix. The analytical formulation is developed based on Eringen's nonlocal elasticity theory to account small scale effect. After developing the formal solution of the mathematical model consisting of partial differential equations, the frequency equations have been analyzed numerically by using the nonlinear foundations supported by Winkler-Pasternak model. The solution is obtained by ultrasonic wave dispersion relations. Parametric work is carried out to scrutinize the influence of the non local scaling, magneto-mechanical loadings, foundation parameters, various boundary condition and length on the dimensionless frequency of nanotube. It is noticed that the boundary conditions, nonlocal parameter, and tube geometrical parameters have significant effects on dimensionless frequency of nano tubes. The results presented in this study can provide mechanism for the study and design of the nano devices like component of nano oscillators, micro wave absorbing, nano-electron technology and nano-electro- magneto-mechanical systems (NEMMS) that make use of the wave propagation properties of armchair single-walled carbon nanotubes embedded on polymer matrix.

Frequency characteristics of a multiferroic Piezoelectric/LEMV/CFRP/Piezomagnetic composite hollow cylinder under the influence of rotation and hydrostatic stress

Selvamani, R.,Mahesh, S.,Ebrahimi, F. Techno-Press 2021 Coupled systems mechanics Vol.10 No.2

An analytical model is consider to scrutinize axisymmetric wave propagation in multiferroic hollow cylinder with rotating and initial stressed forces, where a piezomagnetic (PM) material layer is bonded to a piezoelectric (PE) cylinder together by Linear elastic materials with voids. Both distinct material combos are taken into account. Three displacement potential functions are introduced to uncouple the equations of motion, electric and magnetic induction. The numerical calculations are carried out for the non-dimensional frequency by fixing wave number and thickness. The arrived outputs are plotted as the dispersion curves for different layers. The results obtained in this paper can offer significance to the application of PE/PM composite hollow cylinder via LEMV and CFRP layers for the acoustic wave and microwave technologies.

Wave propagation in a generalized thermo elastic circular plate immersed in fluid

Selvamani, R.,Ponnusamy, P. Techno-Press 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.46 No.6

In this paper, the wave propagation in generalized thermo elastic plate immersed in fluid is studied based on the Lord-Shulman (LS) and Green-Lindsay (GL) generalized two dimensional theory of thermo elasticity. Two displacement potential functions are introduced to uncouple the equations of motion. The frequency equations that include the interaction between the plate and fluid are obtained by the perfect-slip boundary conditions using the Bessel function solutions. The numerical calculations are carried out for the material Zinc and the computed non-dimensional frequency, phase velocity and attenuation coefficient are plotted as the dispersion curves for the plate with thermally insulated and isothermal boundaries. The wave characteristics are found to be more stable and realistic in the presence of thermal relaxation times and the fluid interaction.

Understanding of Pulse Voltage Response Analysis for Degradation in XLPE Cable Using Equivalent Circuit Model

Selvamany Priya,Varadarajan Gowri Sree 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.5

Charge (Q–t) characteristic plays a signifi cant role in the insulation undergoing irreversible aging condition of the cable. In this study, the pulse voltage is used as a diagnostic method based on water tree detection. The mechanism of residual charge accompanied in the degraded insulation part using Maxwell–Wagner model by numerical analysis is performed. The charge intensity of healthy and degraded cable for an approximate model of 6.6 kV and the actual model of 66 kV single-core, XLPE insulated cable was considered for simulation analysis. The eff ect of DC voltage, peak pulse voltage, and a number of pulses on the amount of charge was the subject of our research. The residual charges were increased, which indicates the severely degraded conformity in the tested cable compared with the conventional method. Moreover, the eff ect of ‘fast pulse’ 4 ns wide and ‘slow pulse’ 1.5 ms wide has been applied and its behavior is quantitatively assessed by simulation test using an actual cable model. Various studies have emphasized using this pulse and identifi cation to seek electrical current signals associated with the water-treeing region. The ‘fast pulse’ signal generates an oscillatory response, contains a 143–585 pC charge, and the ‘slow pulse’ signal generates a non-oscillatory response containing 2.4–9.5 μC charge originate at the water treeing region.

Wave propagation in a generalized thermo elastic circular plate immersed in fluid

R. Selvamani,P. Ponnusamy 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.46 No.6

In this paper, the wave propagation in generalized thermo elastic plate immersed in fluid is studied based on the Lord-Shulman (LS) and Green-Lindsay (GL) generalized two dimensional theory of thermo elasticity. Two displacement potential functions are introduced to uncouple the equations of motion. The frequency equations that include the interaction between the plate and fluid are obtained by the perfectslip boundary conditions using the Bessel function solutions. The numerical calculations are carried out for the material Zinc and the computed non-dimensional frequency, phase velocity and attenuation coefficient are plotted as the dispersion curves for the plate with thermally insulated and isothermal boundaries. The wave characteristics are found to be more stable and realistic in the presence of thermal relaxation times and the fluid interaction.

Thermal-magneto-mechanical stability analysis of single-walled carbon nanotube conveying pulsating viscous fluid

R. Selvamani,M. Mahaveer Sree Jayan,Marin Marin Techno-Press 2023 Coupled systems mechanics Vol.12 No.1

In thisstudy, the vibration problem ofthermo elastic carbon nanotubes conveying pulsating viscous nano fluid subjected to a longitudinal magnetic field is investigated via Euler-Bernoulli beam model. The controlling partial differential equation of motion is arrived by adopting Eringen's non local theory. The instability domain and pulsation frequency of the CNT is obtained through the Galerkin's method. The numerical evaluation of thisstudy is devised by Haar wavelet method (HWM). Then, the proposed model is validated by analyzing the critical buckling load computed in presentstudy with the literature. Finally, the numerical calculation ofsystem parameters are shown as dispersion graphs and tables over non local parameter, magnetic flux, temperature difference, Knudsen number and viscous parameter.

Construction of methanol sensing Escherichia coli by the introduction of novel chimeric MxcQZ/OmpR two-component system from Methylobacterium organophilum XX

Vidhya Selvamani,Murali Kannan Maruthamuthu,Kulandaisamy Arulsamy,엄경태,홍순호 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.6

Methylobacterium organophilum XX is a type II facultative methylotroph that can grow on methanol. In M. organophilum XX, the MxcQ/MxcE two-component system (TCS) is involved in methanol metabolism. EnvZ/OmpR in E. coli TCS was exploited to develop a methanol biosensor by engaging the MxcQ/MxcE TCS system. The MxcQZ/ OmpR methanol sensing chimeric TCS was constructed by integrating the sensing domain of M. organophilum MxcQ with the transmitter domain of E. coli EnvZ. The response regulator of the chimeric TCS system is OmpR, which regulates the expression of the ompC and gfp. The expression of ompC was monitored by real-time quantitative PCR analysis. The expression of gfp also confirmed the expression of the ompC. The maximum expression of ompC and gfp occurred with 0.05% of methanol, and the expression started to decline with further increases in methanol concentration. This system delivers rapid detection of methanol in the environment.

Engineering Chimeric Two-component System into Escherichia coli from Paracoccus denitrificans to Sense Methanol

Vidhya Selvamani,Irisappan Ganesh,Murali Kannan Maruthamuthu,엄경태,홍순호 한국생물공학회 2017 Biotechnology and Bioprocess Engineering Vol.22 No.3

Escherichia coli does not have the methanol sensing apparatus, was engineered to sense methanol by employing chimeric two-component system (TCS) strategy. A chimeric FlhS/EnvZ (FlhSZ) chimeric histidine kinase (HK) was constructed by fusing the sensing domain of Paracoccus denitrificans FlhS with the catalytic domain of E. coli EnvZ. The constructed chimeric TCS FlhSZ/OmpR could sense methanol by the expression of ompC and gfp gene regulated by ompC promoter. Real-time quantitative PCR analysis and GFP-based fluorescence analysis showed the dynamic response of the chimeric TCS to methanol. The expression of ompC and the gfp fluorescence was maximum at 0.01 and 0.5% of methanol, respectively. These results suggested that E. coli was successfully engineered to sense methanol by the introduction of chimeric HK FlhSZ. This strategy can be employed for the construction of several chimeric TCS based bacterial biosensors for the development of biochemical producing recombinant microorganisms.

Engineering of Recombinant Escherichia coli Towards Methanol Sensing Using Methylobacterium extroquens Two-component Systems

( Vidhya Selvamani ),( Irisappan Ganesh ),( Sowon Chae ),( Murali Kannan Maruthamuthu ),( Soon Ho Hong ) 한국미생물 · 생명공학회 2020 한국미생물·생명공학회지 Vol.48 No.1

Five genes (mxbDM, mxcQE and mxaB) are responsible for the transcription of methanol oxidation genes in Methylobacterium strains. Among these, MxbDM and MxcQE constitute the two-component system (TCS) regulating methanol metabolism. In this study, we integrated the methanol-sensing domain of MxbD and MxcQ with the EnvZ/OmpR from Escherichia coli. The domain-swapping strategy resulted in chimeric histidine kinases (HK’s) MxbDZ and MxcQZ AM1 containing recombinant E. coli. Real-time quantitative PCR was used to monitor OmpC expression mediated by the chimeric HK and response regulator (RR) OmpR. Further, an ompC promoter based fluorescent biosensor for sensing methanol was developed. GFP fluorescence was studied both qualitatively and quantitatively in response to environmental methanol. GFP measurement also confirmed ompC expression. Maximum fluorescence was observed at 0.05% methanol and 0.01% methanol using MxbDZ and MxcQZ AM1, respectively. Thus the chimeric HK containing E. coli were found to be highly sensitive to methanol, resulting in a rapid response making them an ideal sensor.

Wave propagation in a nonlocal prestressed piezoelectric polygonal plate with non-homogeneity and hygroscopic effect

Rajendran Selvamani,Hepzibah Christinal,Farzad Ebrahimi Techno-Press 2023 Advances in materials research Vol.12 No.4

The humid thermal vibration characteristics of a nonhomogeneous thermopiezoelectric nonlocal plate of polygonal shape are addressed in the purview of generalized nonlocal thermoelasticity. The plate is initially stressed, and the three-dimensional linear elasticity equations are taken to form motion equations. The problem is solved using the Fourier expansion collocation method along the irregular boundary conditions. The numerical results of physical variables have been discussed for the triangle, square, pentagon, and hexagon shapes of the plates and are given as dispersion curves. The amplitude of non-dimensional frequencies is tabulated for the longitudinal and flexural symmetric modes of the thermopiezoelectric plate via moisture and thermal constants. Also, a comparison of numerical results is made with existing literature, and good agreement is reached.