Open Access Original Research Article

Ion Cyclotron (IC) Oscillations Excited by Nonlinear Waves Propagating in Collision-free Auroral Ionosphere

J. Z. G. Ma, J.- P. St.-Maurice

Physical Science International Journal, Page 1-22
DOI: 10.9734/PSIJ/2016/29209

We study ion cyclotron (IC) oscillations activated by a stochastic, strong space-charge electric wavefield E of nonlinear waves propagating auroral ionosphere. E is in a plane perpendicular to the ambient magnetic field B. The word “strong” means that (1) the conventional linear plasma wave model connected to a perturbed electric field is not suitable to be employed; (2) the E × B drift is comparable to (even higher than) the thermal speed of particles, and drive them away from the initial thermal equilibrium. A physical model is set up for a dense cluster of electron soliton trains with which a magnetic flux tube is teeming. Then, the collision-free Boltzmann equation is solved under the condition that E is temporally constant. With a nonzero initial guiding-center (GC) velocity, ions are found to follow a double-circle trajectory in velocity space with an IC oscillation frequency ω which shifts from the magnetic gyrofrequency Ω = eB/m(where eand mi are the charge and mass of the singly ionized ions, respectively). Furthermore, the “constant” condition
is relaxed by using a simple stochastic E which has 10-step random strengths in 10 different time intervals. The accommodation of ω (as well as other parameters) is illustrated in response to the E switches. At last, the work is generalized by using two random-number generators for the strength and time, respectively. In this case, ω can be shifted to several Ω values. This result is in good agreement with what FAST satellite measured in auroral field-aligned current regions.

Open Access Original Research Article

Influence of Annealing Temperature on the Physical Properties of Cu2SnSe3 Thin Films Prepared by Thermal Vacuum Evaporation Technique

Mohd Amirul Syafiq Mohd Yunos, Zainal Abidin Talib, Wan Mahmood Mat Yunus

Physical Science International Journal, Page 1-10
DOI: 10.9734/PSIJ/2016/29024

Ternary compound of semiconductor polycrystals Copper Tin Selenide, Cu2SnSe3, thin films have been prepared by vacuum thermal evaporation technique on well-cleaned glass substrate and annealed in purified nitrogen atmosphere from room temperature to 500°C for different annealing temperature. The annealing effects on surface morphologies, elemental compositions, and electrical behaviour of these films have been investigated using Scanning Electron Microscope (SEM), Energy Dispersive X-Ray (EDX), and Van der Pauw techniques. EDX studies showed that increasing the annealing temperature resulted in drastic loss of Cu content. It is observed that elemental compositions of the Cu2SnSe3 thin films were close to the ideal stoichiometric value 2:1:3. The annealed Cu2SnSe3 thin films were found to be p-type semiconductor with activation energy, ΔEa, of 0.018 eV obtained from I-V characteristic analysis.

Open Access Original Research Article

Criticality Study for Large Masses of Low Enriched Uranium Samples in an Active Well Neutron Coincidence Counter

W. El-Gammal

Physical Science International Journal, Page 1-9
DOI: 10.9734/PSIJ/2016/29206

A criticality study has been conducted while verifying large masses of Low Enriched Uranium (LEU) samples in an Active Well Neutron Coincidence Counter (AWCC). Fissile material mass limits were determined for some setup conditions to assure safe operation of the counter. The work was performed at the Department of Safeguards and Physical Protection, Nuclear and Radiological Regulatory Authority (ENRRA), during the period from February to December 2015.

The AWCC device was assumed to be employed in verification activities including measurements of different Nuclear Material (NM) samples in different setup configurations, forms and conditions. The MCNP5 code was used to estimate keff of relatively large masses of LEU in different forms including uranium oxide powder, compacts and fuel rods. All calculations were performed assuming the operation of the AWCC in active thermal mode at maximum capacity of its cavity. The uranium powder samples were modeled as dry and with different values of water contents. For compacts and fuel rods, the calculations were performed with and without the existence of moderating materials in the cavity of the device.

All studied cases were found to be subcritical except for a few cases of uranium oxide powder containing water. Criticality was reached for samples containing 235U masses ranged between 1.5 to 8.0 kg with corresponding percent water content from 67 to 25. The estimated mass limits of LEU samples with certain characteristics that could be safely verified in the device are presented.

 

Open Access Original Research Article

Structure of the Atomic Nuclei in the Universe Model with Minimal Initial Entropy

Petro O. Kondratenko

Physical Science International Journal, Page 1-12
DOI: 10.9734/PSIJ/2016/28694

In this paper we show on the base of new ideas about the origin and evolution of the Universe, that in three-dimensional space the fundamental particles should have electric charges equal to 0, ±e, ±2e, ±3e, what corresponds to the neutron and three pairs of light stable nuclei (hydrogen, helium, lithium). All heavy (Z ≥ 4) cores are presented in the form of molecular structures consisting of light nuclei; there are shown the reasons of instability of the nuclei in the ground and excited states. The hierarchy of bosons which are responsible for the interaction between particles in different hierarchical layers of fiber space Super-Universe is given.

 

Open Access Original Research Article

Radiation Effects on Heat and Mass Transfer of MHD Fluid over a Permeable Stretching Sheet with Buoyancy Forces

J. Venkata Madhu, B. Shashidar Reddy, M. N. Rajasekhar

Physical Science International Journal, Page 1-10
DOI: 10.9734/PSIJ/2016/29107

This article numerically studies the influence of Buoyancy effects and thermal radiation of the nonlinear MHD flow with heat and mass transfer characteristics of an incompressible, viscous, electrically conducting and Boussinesq fluid along a permeable vertical stretching sheet. A magnetic field is applied transversely to the direction of the flow. The basic equations governing the flow, heat transfer, and concentration are reduced to a set of non linear ordinary differential equations by using appropriate similarity transformation. The non linear ordinary differential equations are first linearised using Quasi-linearization and solved numerically by an implicit finite difference scheme. Then the system of algebraic equations is solved by using Gauss-Seidal iterative method. The effects of physical parameters on the velocity, temperature, and concentration profiles are illustrated graphically. Velocity, Temperature and Concentration profiles drawn for different controlling parameters reveal that the flow field is influenced appreciably by the presence of buoyancy effects, thermal radiation, and magnetic field.

 

Open Access Original Research Article

Design and Implementation of Electronics Equipment Security Lock System

D. T. Agana, F. N. Gesa, C. A. Chile

Physical Science International Journal, Page 1-15
DOI: 10.9734/PSIJ/2016/29472

The work presents the design and implementation of a Central Electronic Equipment Security Lock System - a security and access control system for used in public and private organisations as a means to restrict unauthorized access to valuable electronics equipment. The system interfaced the microcontroller (PIC16F877A) to the 16 x 2 Liquid Crystal Display (LCD) which is used to communicate/display the visual outputs to the user, multiplexed keypad (4 x 3) as input unit, three relays (30A, 12V) that serve as isolators and the buzzer-a warning device that gives an alarm when a wrong password is encoded. When the correct password is entered, the system grant access to the user and upon entry of a wrong code three times, the system gives a sound alarm via a buzzer showing that unauthorized person has tempered with the property being secured. By this, the user can also choose which equipment to grant access to (switch on) or not. The system is programmed using Assembly language and MPLAB compiler IDE to grant access to a single load or multiple loads either automatically or manually. The regulated power supply of the system showed a negligible difference of (4.9 V and 11.8 V compared to the ideal values of 5.0 V and 12.0 V respectively. Also, the system operation timing tests carried out with respect to real time showed a mean variation of 0. 005 min (0.30 sec). These errors are quite negligible hence the system is certified to be of optimal performance. The designed and implemented Central Electronic Equipment Security Lock System therefore finds suitable application in security and access control systems for use in public and private organisations as a means of restricting unauthorized access to valuable electronics equipment.

 

Open Access Original Research Article

Free Energy Determination of a Binary Alloy Around the Equilibrium Based on the Order Parameter

EL Azzouzi Fatima, EL Khomssi Mohammed

Physical Science International Journal, Page 1-8
DOI: 10.9734/PSIJ/2016/29954

In this paper, we have determined the free energy of a binary alloy for any order and it is showed that the number of equilibrium states of the system is obtained by the Taylor expansion to the 4-th order choice. We explicitly determine the stable states of alloy which are characterized by the free energy.