Open Access Original Research Article

Intermittency of Regular and Chaotic Motion in the Dynamic System with Multiple Lorenz Attractors

Vadim G. Prokopenko

Physical Science International Journal, Page 1-9
DOI: 10.9734/PSIJ/2018/42359

A new type of intermittency observed in an auto stochastic dynamic system with a multicomponent chaotic attractor consisting of several Lorentz attractors is considered. It is shown that it is caused by the coexistence of two types of intermittency: "chaos – chaos" and "quasiperiodic motion – chaos". The main statistical characteristics of this movement are also given.

Open Access Original Research Article

Excess Parameters of Binary Mixtures of 1, 2-Dimethoxyethane-Propylene Carbonate and 2-Methoxyethyl Ether-Propylene Carbonate

John N. Obowu, Millicent U. Ibezim-Ezeani, Augustine A. Abia

Physical Science International Journal, Page 1-9
DOI: 10.9734/PSIJ/2018/42560

The excess parameters associated with liquid mixtures were evaluated in order to ascertain the relative strength of intermolecular interactions in binary mixtures of 1,2-Dimethoxyethane-Propylene Carbonate (DME-PC) and 2-Methoxyethyl ether-Propylene Carbonate (DGM-PC). The density and viscosity of pure components of Propylene Carbonate (PC), 1,2-Dimethoxyethane (DME), 2-Methoxyethyl ether (DGM) and mixtures (DME-PC and DGM-PC) were measured within the composition range of 0 to 100% at temperatures of 298.15, 308.15, 318.15, 328.15 and 338.15 K. Experimental density and viscosity values decreased with an increase in system temperature and mole fractions of DME and DGM. Mathematical operations were conducted from the density and viscosity data at 298.15 K to resolve the magnitude of excess molar volume (VmE), excess viscosity (ηE), excess Gibbs free energy of activation of viscous flow (G*E) and Grunberg-Nissan interaction parameter (d). These parameters were mainly of negative value, which signified the dominance of dipole-dipole interactions within DME-PC and DGM-PC solvent systems. The existence of interactions between the components of the binary mixtures was also reflected by the non-zero result findings for values of excess parameters.

Open Access Original Research Article

Weak Competition and Ideally Distributed Populations in a Cooperative Diffusive Model with Crowding Effects

Md. Kamrujjaman

Physical Science International Journal, Page 1-16
DOI: 10.9734/PSIJ/2018/42472

We study a dynamic model describing the cooperation-competition between two species, where the first species diffuses along a smooth distribution function while the second is dispersive randomly. The analysis is designed for weak competition with corresponding coefficients and by considering different resource functions. It is shown that the directed diffusion population has evolutionary advantages to design its own niche. The higher carrying capacity is an important issue of persistence. If there is a combination of two strategies adopted by the two species then the ideal free distribution is attained and the coexistence steady state is a global attractor.

Open Access Original Research Article

Seasonal Variations of Ionospheric Scintillations and Total Electron Content over a Terrestrial Point within Magnetic Anomaly Region

Rufus Sola Fayose

Physical Science International Journal, Page 1-7
DOI: 10.9734/PSIJ/2018/41782

The dual frequency signals from the GPS satellites were recorded and analyzed to study the ionospheric variations in terms of Total Electron Content (TEC) as well as the Scintillation index (S4). Seasonal variations of Total Electron Content as well as the ionospheric scintillation activity within the Magnetic anomaly region were examined. TEC maximizes during Equinox months (March, April, September, October), and minimizes during the winter months (November, December, January, February), with intermediate values during summer months (May, June, July, August), showing a semiannual variation. The semiannual variation of TEC was asymmetry with a maximum in Spring Equinox. The average value for TEC in 2007, 2008 and 2009 were 48.34, 42.89 and 45.64 TECU respectively while the average of Scintillation index (S4) for each of the years was 0.103.

Open Access Original Research Article

Energetics of the Basic Allotropes of Carbon

S. G. Abdu, M. A. Adamu, M. Y. Onimisi

Physical Science International Journal, Page 1-10
DOI: 10.9734/PSIJ/2018/41778

An effort was made in this work to calculate the total ground state energy and electronic band structure of Fullerenes (C60), Graphite and Diamond using FHI-aims Density Functional Theory (DFT) code. The density functionals used are the local-density approximation (LDA) in the parameterization by Perdew and Wang 1992, Perdew and Zunger 1981, the generalized gradient functional PBE, and PBE+vdW approach as defined by Tkatchenko and Scheffler. The results obtained from the computations of the ground state energies of diamond, fullerenes and graphite were -2072.569 eV, -1027.178 eV and -2070.938 eV respectively. These results agree well when compared to the various exchange and correlation functionals used in this study. Similarly, the results obtained from the computations of the Kohn Sham electronic band gaps of graphite and diamond were 0.00072 eV and 5.57611 eV, respectively. These are also in agreement when compared to the experimental values of 0eV and 5.5eV. These band gaps are within reasonable overestimation errors of 0.0007 eV and 0.08 eV respectively. However, fullerenes band gap of 8.21131eV is not in agreement with the theoretical and experimental values of 1.83eV and 2.3eV, respectively. This is probably due to the Bucky-ball nature of Fullerenes as well as the lattice constants and physical settings used.