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Life Time Maximization of Homogeneous and Heterogeneous Ad Hoc Networks
Full text linkIn this paper, we address the problem of energy efficient routing in homogeneous and heterogeneous wireless ad hoc networks aiming at maximize the network lifetime. We define the network lifetime as the number of transmissions the node can perform until the first node fails due to battery exhaustion. In static networks we find a routing (spanning) tree which maximizes the network lifetime without tree update. We have proposed a Global weighted incremental power model and Global weighted post sweep for extending the life time of heterogeneous wireless ad hoc wireless network that gives better performance than the WBIP (Weighted Broadcast Incremental Protocol) implementation. We consider the amount of energy the node has compared to the maximum energy in network as the parameter in the cost metric function for constructing a efficient routing tree
Linear and weakly nonlinear stability analyses of Rayleigh–Bénard convection in water–copper–alumina hybrid nanoliquid bounded by rigid isothermal boundaries is studied analytically. A single-phase description is used for the nanoliquid. Using a minimal Fourier series representation and an appropriate scaling a classical Lorenz model for rigid isothermal boundaries is derived. The Lorenz model is transformed to the Ginzburg–Landau model using the renormalization group method. The solution of the Ginzburg–Landau model is used to arrive at the expression of the Nusselt number. The study shows that the presence of two nanoparticles in water is to increase the coefficient of friction, advance the onset of convection and enhance the heat transfer. Further, it is shown that compared to a single nanoparticle the combined influence of two nanoparticles is more effective on heat transfer. The percentage of heat transfer enhancement in water due to Al2O3-Cu hybrid nanoparticles is almost twice that of Al2O3 nanopartcles. It is found that the hybrid nanoparticles of Al2O3-Cu intensify convection in water more than the mono nanoparticles of Al2O3 and the plots of stream function and isotherm point to this fact. The effect of the physically realistic rigid boundaries is to inhibit the onset of convection when compared with that of free boundaries. © 2019, EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature.
No full textLinear and weakly nonlinear stability analyses of Rayleigh–Bénard convection in water–copper–alumina hybrid nanoliquid bounded by rigid isothermal boundaries is studied analytically. A single-phase description is used for the nanoliquid. Using a minimal Fourier series representation and an appropriate scaling a classical Lorenz model for rigid isothermal boundaries is derived. The Lorenz model is transformed to the Ginzburg–Landau model using the renormalization group method. The solution of the Ginzburg–Landau model is used to arrive at the expression of the Nusselt number. The study shows that the presence of two nanoparticles in water is to increase the coefficient of friction, advance the onset of convection and enhance the heat transfer. Further, it is shown that compared to a single nanoparticle the combined influence of two nanoparticles is more effective on heat transfer. The percentage of heat transfer enhancement in water due to Al2O3-Cu hybrid nanoparticles is almost twice that of Al2O3 nanopartcles. It is found that the hybrid nanoparticles of Al2O3-Cu intensify convection in water more than the mono nanoparticles of Al2O3 and the plots of stream function and isotherm point to this fact. The effect of the physically realistic rigid boundaries is to inhibit the onset of convection when compared with that of free boundaries. © 2019, EDP Sciences, Springer-Verlag GmbH Germany, part of Springer Nature.
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Petrodollar and World Economy
No full textThe quadrupling of the oil price by the OPEC in 1973 was a poignant event in the post-war development of the world economy. Which measures and mechanisms conduced to the international income redistribution necessitated by the hoisting of the oil prices in the past five years
Synthesis, characterization, in vitro biological evaluation and molecular docking studies of newly synthesized mononuclear lanthanum(III) complexes of N,N'-bis(2-aminoethyl)oxamide and phenanthroline bases
No full textFour lanthanum(III) complexes were newly synthesized using the ligand N,N'-bis(2-aminoethyl)oxamide (1) and phenanthroline bases [La(oxae)2(NO3)2](NO3) (2) [La(oxae)(bpy)](NO3)3 (3), [La(oxae)(phen)](NO3)3 (4) and [La(oxae)2(dppz)](NO3)3 (5) and characterized by 1H-NMR, IR, UV–Visible spectroscopic analyses, ESI-Mass spectrometric measurements, molar conductivities, and cyclic voltammetric measurements. Complex 2 was found to be 1:1 electrolyte and complexes 3, 4 and 5 were 1:3 electrolytes. The redox ehavior of the complexes was confirmed by cyclic voltammetry. The interactions of 1 and its complexes (2, 3, 4 and 5) with calf thymus DNA (CT-DNA) were studied by UV–Visible absorption spectroscopy, cyclic voltammetric studies, viscosity measurements and molecular docking studies. The studies confirmed the highest binding propensity for complex 5 (Kb = 2.26 × 106 ± 7) in the reduced state through the intercalation method. Molecular docking studies revealed that complex 5 was found to bind strongly with the DNA molecule due to intercalation with a more negative binding energy ΔG = - 8.6 kcal/mol having an association constant (Ka) = 0.892 µM. The oxidative cleavage of SC pUC19 DNA by La(III) complexes was confirmed by the Agarose gel electrophoresis method. Of all the compounds tested, complex 5 exhibited the highest cleavage ability (94%) in the presence of H2O2 in the major groove region. The MTT assay revealed the highest antiproliferative activity of complex 5 against MCF-7 cell lines at IC50 value is 21.86 µM. The complexes have been tested for antibacterial activities wherein at 50 µg mL−1, complex 5 inhibits the growth of K. pneumonia and at 100 µg mL−1, ligand oxae (1) and its complex 2 were active against E. coli and K. pneumonia; complex 4 inhibited the growth of E. coli, K. pneumonia and B. subtilis. The antioxidant activities showed that complex 2 had the highest chelation ability towards Fe2+. © 2022 Elsevier B.V