Majumdar K.C.,Kalyani University |
Maji P.K.,Bidhan Chandra College |
Chattopadhayay S.K.,Shantipur College
Letters in Organic Chemistry | Year: 2014
Pyrimidine annulated sulfur heterocycles have been synthesized through tributyltin hydride-mediated radical reaction. This gave straight forward synthesis of tricyclic compound as well as spiro heterocyclic compounds. The reactions have been simple, straight forward and have been carried out in mild conditions. © 2014 Bentham Science Publishers.
PubMed | Bidhan Chandra College, Hooghly Mohsin College and University of Burdwan
Type: Journal Article | Journal: Chaos (Woodbury, N.Y.) | Year: 2016
We explored analytically the oscillation quenching phenomena (amplitude death and parameter dependent inhomogeneous steady state) in a coupled third order phase locked loop (PLL) both in periodic and chaotic mode. The phase locked loops were coupled through mean field diffusive coupling. The lower and upper limits of the quenched state were identified in the parameter space of the coupled PLL using the Routh-Hurwitz technique. We further observed that the ability of convergence to the quenched state of coupled PLLs depends on the design parameters. For identical systems, both the systems converge to the homogeneous steady state, whereas for non-identical parameter values they converge to an inhomogeneous steady state. It was also observed that for identical systems, the quenched state is wider than the non-identical case. When the system parameters are so chosen that each isolated loop is chaotic in nature, we observe narrowing down of the quenched state. All these phenomena were also demonstrated through numerical simulations.
Chakraborty A.,Satyendra Nath Bose National Center for Basic science |
Mukherjee G.,Bidhan Chandra College |
Manna S.S.,Satyendra Nath Bose National Center for Basic science
Physica A: Statistical Mechanics and its Applications | Year: 2015
Three different earthquake seismic data sets are used to construct the earthquake networks following the prescriptions of Abe and Suzuki (2004). It has been observed that different links of this network appear with highly different strengths. This prompted us to extend the study of earthquake networks by considering it as the weighted network. Different properties of such weighted network have been found to be quite different from those of their un-weighted counterparts. © 2015 Elsevier B.V.
Panda S.K.,Bidhan Chandra College |
Shin H.,Sungkyunkwan University
Materials Research Innovations | Year: 2015
Atomic layer deposition onto highly porous anodic aluminium oxide templates was used to fabricate the arrays of TiO2 nanotubes. The as-prepared nanotubes were amorphous and subsequently transformed to crystalline phase, anatase, by thermal annealing at the temperature of 400-500 °C. These nanotube arrays were used for Li-ion storage as anode materials. A comparative study for the electrochemical performance of amorphous and crystalline anatase nanotube-array-based anodes has been presented. Amorphous nanotube-array-based anodes showed very high irreversible capacity compared to the anatase ones. Reversible capacity of ∼177 mAh/g was achieved from anatase nanotube-array-based anode, which was close to the maximum obtainable capacity, known as maximum theoretical capacity from bulk anatase phase reported. © W. S. Maney & Son Ltd 2015.
Sarkar B.C.,University of Burdwan |
Chakraborty S.,Bidhan Chandra College
Journal of Engineering Science and Technology Review | Year: 2015
A third order phase locked loop incorporating a resonant type second order filter is a conditionally stable system and shows complicated dynamics including chaotic oscillations for a range of loop parameters. In the face of two co-channel signals, an otherwise stable loop may be thrown into a chaotic state, depending on the relative strength and mutual frequency offset of the input signals. We have predicted the parameter zone for chaotic state of the loop through numerical studies and verified the prediction by hardware experiment. Then we modify the loop structure to incorporate an additional control signal which stabilizes the loop dynamics and removes the chaotic oscillations. The improved response of the loop is established numerically and experimentally. © 2015 Kavala Institute of Technology.
Maji P.K.,Bidhan Chandra College |
Islam R.U.,Birla Institute of Technology |
Bera S.K.,Bidhan Chandra College
Heterocycles | Year: 2014
This review highlights some remarkable achievements made recently in the application of metal-catalyzed processes to the design of multicomponent syntheses of heterocycles. The domino MCRs that are purely based upon metal catalysis opens a vast field for the discovery of new sequences in heterocyclic synthesis. Many of these methods have proven to be the most powerful and are currently applied in target- or diversity-oriented syntheses. These reactions can dramatically reduce the generation of chemical wastes, costs of starting materials, and the use of energy as well as manpower. Moreover, the reaction period can be substantially shortened. This review article aims to report the recent developments devoted to this important area, focusing on the metal catalysis in multicomponent synthesis of heterocycles. © 2014 The Japan Institute of Heterocyclic Chemistry Received, 8th September, 2013.
Mukherjee S.,Indian Institute of Technology Madras |
Gupte N.,Indian Institute of Technology Madras |
Mukherjee G.,Bidhan Chandra College
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010
We identify the statistical characterizers of congestion and decongestion for message transport in model communication lattices. These turn out to be the travel time distributions, which are Gaussian in the congested phase, and logarithmic normal in the decongested phase. Our results are demonstrated for two-dimensional lattices, such the Waxman graph, and for lattices with local clustering and geographic separations, gradient connections, as well as for a one-dimensional ring lattice with random assortative connections. The behavior of the distribution identifies the congested and decongested phase correctly for these distinct network topologies and decongestion strategies. The waiting time distributions of the systems also show identical signatures of the congested and decongested phases. The distributions are explained using a stochastic differential equation to model the transport. © 2010 The American Physical Society.