Advances in Physics Theories and Applications
http://www.iiste.org/Journals/index.php/APTA
The International Institute for Science, Technology and Education (IISTE)en-USAdvances in Physics Theories and Applications2224-719XJournal Cover Page
http://www.iiste.org/Journals/index.php/APTA/article/view/22254
Journal Cover PageJournal Editor43Evaluation of Optical Model Potential using Neutron Induced Cross Section Reactions for Spherical Uranium-235 Isotope up to 20MeV
http://www.iiste.org/Journals/index.php/APTA/article/view/22248
<p>The evaluation is based mainly on the calculations of the nuclear optical model potential and the relevant parameters are collected and selected from References Input Parameter Library (RIPL) which is being developed under the international project coordinated by the International Atomic Energy Agency (IAEA). The analyzing of a complete energy range has been done starting from threshold energy for each reaction. The cross sections are reproduced in fine steps of incident neutron energy with 0.01MeV intervals with their corresponding errors. The recommended cross sections for available experimental data taken from EXFOR library have been calculated for all the considered neutron induced reactions for U-235 isotope. The calculated results are analyzed and compared with the experimental data. The optimized optical potential model parameters give a very good agreement with the experimental data over the energy range 0.001-20MeV for neutron induced cross section reactions <em>(n,f), (n,tot), (n,el), (n,inl), (n,2n), (n,3n), and (n,γ</em>) for spherical U-235 target element.</p> <p><strong>Keywords: </strong>EXFOR nuclear data, induced neutron reactions, 20MeV, recommended cross section, optical model potential.</p>Iman Tarik AL-AlawyRonak Ikram Ali43Performance of FSO Communication System under Various Weather Condition
http://www.iiste.org/Journals/index.php/APTA/article/view/22249
<p>In this paper, the performance FSO communication under different weather condition is theoretically analyzed, using L-PPM modulation technique and a Si PIN photodiodes receiver over FSO channels. Based on the attenuation coefficient of different weather and impacts on a received signal power, SNR, BER, and channel are analyzed. Simulation results indicate that the performance of 16-PPM is more suited for FSO communication.</p> <p><strong>Keywords:</strong> Communications, FSO Communications, Bit Error Rate, Channel Capacity.</p>Mazin Ali A. AliEmad H. Ahmed43A New Derivation of the Time-Dependent Schrödinger Equation from Wave and Matrix Mechanics
http://www.iiste.org/Journals/index.php/APTA/article/view/22250
<p class="abstract">An alternative method is proposed for deriving the time-dependent Schrödinger equation from the pictures of wave and matrix mechanics. The derivation is of a mixed classical–quantum character, since time is treated as a classical variable, thus avoiding any controversy over its meaning in quantum mechanics. The derivation method proposed in this paper requires no ad hoc assumption and avoids going through a second-order differential equation that can be reduced to the well-known time-dependent Schrödinger equation only postulating a complex wavefunction with a time dependence given by , as did by Schrödinger in its original paper of 1926 [1].</p> <p class="keywords"><strong>Keywords:</strong> Schrödinger equation, wave–particle duality, Hermitian operators, commutation relations</p>Luca Nanni43Tomonaga-Luttinger Liquid Exponents of Correlation Functions around Fermi points in the Hubbard Model
http://www.iiste.org/Journals/index.php/APTA/article/view/22251
<p>The correlation functions of one-dimensional Hubbard model in the presence of external magnetic field was investigated through the conformal field technique. The long distance behaviour of the correlation functions and their critical exponents for the model in the presence of a magnetic field are established by solving the dressed charge matrix equations and setting the number of occupancies to one, as an alternative to the usual zero often used by authors in literatures. Our result shows the critical exponents of the correlation function grows monotonically with magnetic field and reduces to definite values at zero magnetic field around various Fermi points.</p> <p><strong>Keywords: </strong>Correlation functions, magnetic field, critical exponents</p> <p><strong> </strong></p>Nelson O. NenuweJohn O.A. Idiodi43Soret and Dufour Effects on Mixed Convective Heat and Mass Transfer Flow in a Rectangular Duct with Heat Generating Sources
http://www.iiste.org/Journals/index.php/APTA/article/view/22252
<p>In this paper we investigated the combined influence of dissipation, heat sources, Soret and Dufour effects on the convective heat and mass transfer flow of a viscous fluid through porous medium in a rectangular cavity using Darcy model. Making use of the incompressibility the governing non-linear coupled equations for the momentum, energy and diffusion are derived in terms of the non-dimensional stream function, temperature and concentration. The Galerkin finite element analysis with linear triangular elements is used to obtain the Global stiffness matrices for the values of stream function, temperature and concentration. These coupled matrices are solved using iterative procedure and expressions for the stream function, temperature and concentration are obtained as linear combinations of the shape functions. The behaviour of temperature, concentration, Nusselt number and Sherwood number are discussed computationally for different values of the non-dimensional governing parameters.<strong></strong></p> <p><strong>Keywords: </strong>Soret and Dufour effects, heat sources, rectangular duct, finite element analysis.</p>C. Sulochana H. Tayappa43Our Radiant Sun is Condensed and Cold
http://www.iiste.org/Journals/index.php/APTA/article/view/22253
<p>Some years ago I proved that the Sun behaves as one large hydrogen atom. This gives us a new unique explanation of the nature of the Sun because it means – according to Bose-Einstein’s condensation theory - that the Sun must be at the highest degree of condensation and coldness. Because we proved also that the radius of the Sun is proportional to that of hydrogen atom, therefore the radii of hydrogen atoms in the Sun’s core must be at their shortest value forming the recently discovered small neutron star in that core , while at the outermost layer of the Sun called corona like that at the outermost level of energy in hydrogen atom (beyond fifth level) every electron here and there is free from the attraction of the proton, and the daylight on the Earth takes place when the free energetic electrons of solar corona interact with the gaseous atmosphere of the Earth causing its atoms to glow when the Earth faces the Sun through its motion around its axis, and because the coronal electrons near the Sun have less free energies due to strong solar attraction measuring to those at farther distance from the Sun therefore we can understand why the Earth on its orbit is hottest when it is farthest from the Sun not when it is closes.</p> <p><strong>Keywords</strong>: hydrogen star, hydrogen atom, Bose-Einstein theory, condensation state , Sun’s layers , neutron star.</p>Salah Eid43