Barddhamān, India
Barddhamān, India

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A facile and sensitive electrochemical sensor was developed for selective and simultaneous determination of DA and PA using a glassy carbon electrode with electropolymerized AHMP thin film (Poly-AHMP/GCE). The modified electrode showed well-defined redox peaks for DA and PA with enhanced peak currents and reduced over potential while bare glassy carbon electrode showed a broad peak. Poly-AHMP/GCE separates overlapped and sluggish signals of DA and PA into two well-distinguished redox peaks with large enough anodic peaks separation about 240 mV. On varying the pH of the solution from 3 to 9, we observed a good separation of redox peaks of DA and PA at pH 7 with enhanced peak currents. Differential pulse voltammetric technique (DPV) is employed for the selective and simultaneous determination of DA and PA. Under the optimal experimental condition, the anodic peak currents of DA and PA increased linearly within the concentration ranges 2.5–25 μM and 2–20 μM with correlation coefficients of 0.999, 0.991, respectively. The detection limit of DA and PA were found to be 0.20 and 0.15 μM, respectively (S/N = 3) by DPV method. The modified electrode was successfully utilized to determine DA and PA in real samples such as dopamine injection and paracetamol tablets. © 2017 Elsevier B.V.

Maheshvaran K.,Gandhigram Rural University | Veeran P.K.,Vivekananda College | Marimuthu K.,Gandhigram Rural University
Solid State Sciences | Year: 2013

Eu3+ doped boro-tellurite glasses (69 - x)B2O 3 + xTeO2 + 15Na2CO3 + 15NaF + 1Eu2O3 (where x = 0, 10, 20, 30 and 40 wt%) have been prepared and their structural and optical properties were studied through XRD, FTIR, absorption, luminescence and decay time measurements. The FTIR spectra reveal the presence of B-O-B bond bending vibrations and Te-O-Te or O-Te-O linkage bending vibrations in the prepared glasses. The absorption spectral measurements were used to calculate the bonding parameters (β, δ). The direct, indirect allowed band gap (Eopt), band tail parameter (B) and Urbach energy (ΔE) values of the prepared glasses have also been determined from the absorption spectral measurements. The phonon sideband is observed from the excitation spectra on the higher energy side of the 7F0 → 5D2 transition. The phonon energy (hω) and the electron-phonon coupling constant (g) were also derived from the phonon sideband spectra. Through the luminescence spectra, Judd-Ofelt (JO) intensity parameters (Ωλ, λ = 2, 4 and 6) and the luminescence intensity ratio (R) have been determined. The JO parameters have also been used to calculate the radiative properties like transition probability (A), stimulated emission cross-section (σPE), radiative lifetime (τrad), and branching ratios (βR) for the 5D0 → 7F J (J = 0, 1, 2, 3 and 4) emission transitions of the Eu3+ ions. The experimental lifetime of the 5D0 level is found to be single exponential for all the prepared glasses. The obtained results were discussed and reported in the present work. © 2012 Elsevier Masson SAS. All rights reserved.

Nath D.,Vivekananda College | Roy P.,Indian Statistical Institute
Annals of Physics | Year: 2014

We study (2+1) dimensional massless Dirac oscillator in the presence of perpendicular magnetic and transverse electric fields. Exact solutions are obtained and it is shown that there exists a critical magnetic field Bc such that the spectrum is different in the two regions B>Bc and B

Mukherjee D.,Vivekananda College
Differential Equations and Dynamical Systems | Year: 2016

This paper analyzes a prey–predator system where the prey population is infected by a microparasite. The predator functional response is of a Holling type II. We study three cases for the predator food choice. Persistence conditions are derived when predators attack the healthy and infected prey simultaneously. A persistence condition is also derived when predators consume infected prey only. It is shown that when predators attack healthy prey only, then the system cannot be uniformly persistent. The role of delay is also discussed for a system with the predator consuming both types of prey. The parameters are identified which influence the persistence of all the populations as well as impermanence. Numerical examples are provided to support our results. © 2014, Foundation for Scientific Research and Technological Innovation.

Pahari N.,Vivekananda College
Journal of Optics (India) | Year: 2016

In digital data communication, parity bit plays an important role to check the errors in sending binary information. There are two types of the parity bit generator—one is even parity bit generator and the other is odd parity bit generator. Here a new concept of all optical even and odd parity bit generator and checker schemes are proposed where the optical nonlinear materials are used as switching devices. © 2016 The Optical Society of India

Mukherjee D.,Vivekananda College
Differential Equations and Dynamical Systems | Year: 2014

A refuge model is developed for a resource-based ecosystem. The predator functional responses are taken to be of Holling type I and II, respectively. Stability analyses are carried out for both the cases. Bifurcation phenomenon occurred only for system with Holling type II predator functional response. We identify the parameter which ensures long-term survival of all the populations. The effects of refuges have been established on equilibrium densities of prey and predator population, respectively. The results show that the effects of refuges used by prey increase the equilibrium density of prey population. As far as the predator population is concerned, when prey density at equilibrium level remains below a certain threshold value, increasing the amount of prey refuge can decrease the predator densities. Numerical examples are provided to support our results. © 2013, Foundation for Scientific Research and Technological Innovation.

Mukherjee D.,Vivekananda College
Nonlinear Analysis: Real World Applications | Year: 2016

This paper considers the effect of immigration and refuge on the dynamics of a three species system in which one predator feeds on one of two competing species. Immigration is assumed only for the species which is not attacked by the predator. The main results address the stability of the system. Namely, it is shown that increasing the number of refuges stabilizes the system, whereas the opposite holds true by increasing the immigration rate. Also, one result about the persistence of the system and one concerning the global stability of the coexistence equilibrium are presented. Some numerical simulations illustrate the obtained results. © 2016 Elsevier Ltd. All rights reserved.

Baskar K.,Entomology Research Institute | Baskar K.,Vivekananda College | Ignacimuthu S.,Entomology Research Institute
Chemosphere | Year: 2012

Ononitol monohydrate isolated from the ethyl acetate extract of Cassia tora L. using column chromatography was evaluated for its antifeedant, larvicidal and growth inhibitory activities against Helicoverpa armigera and Spodoptera litura at different concentrations of 125, 250, 500 and 1000. ppm. Leaf disc no-choice method was used for the bioassay. The compound showed significant antifeedant, larvicidal and pupicidal activities against H. armigera and S. litura. The compound also prolonged the larval-pupal duration of the insect at all the tested concentrations. The activities were concentration dependent for both the insects. Ononitol could be used as an agent to prepare botanical new pesticidal formulations. © 2012 Elsevier Ltd.

We calculate information theoretic spreading measures of the position and momentum wave functions of the symmetric trigonometric RoseMorse potential for the states n = 0, 1, 2, 3, 4, 5. The position space Renyi entropy, Fisher entropy and their corresponding entropic lengths are presented analytically for n = 0, 1, 2, 3, 4, 5. The momentum space Renyi entropy and the Renyi lengths are calculated analytically for n = 0,1 and are calculated numerically for n = 2, 3, 4, 5. We also calculated the Fisher entropy and the Fisher lengths in the momentum space numerically for n = 0, 1, 2, 3, 4, 5. © 2014 The Royal Swedish Academy of Sciences Printed in the UK.

Mukherjee D.,Vivekananda College
World Journal of Modelling and Simulation | Year: 2016

In this paper, a delayed nutrient-plant-herbivore system with plant toxicity is investigated. In absence of delay, local stability of boundary and interior equilibrium points are discussed. Persistence criteria is derived. By considering the delay as bifurcation parameter, local stability and Hopf bifurcation of periodic solution are shown. Further, we also study the direction of Hopf bifurcations and stability of bifurcated periodic solutions by applying the normal form theory and center manifold theorem. From our numerical simulations, we observe that delay plays an important role on the dynamic behaviour of our system.

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