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International Review
of PHYSICS - Papers
 Energy
Levels, Oscillator Strengths and Transition Probabilities for Fine-Structure
Transitions in Ar VI, K VII, and Ca VIII
by W.O.Younis, S.H.Allam
Abstract -
Fine-structure energy levels, oscillator strengths and transitions
probabilities for transitions among the fine-structure levels of the
terms belonging to the 1s22s22p63s2np
(2P), 1s22s22p63s2nd
(2D) (n= 3-5) and 1s22s22p63s2ns
(2S), 1s22s22p63s2nf
(2F) (n= 4, 5) configurations of the Al-like ions Ar VI, K
VII, and Ca VIII have been calculated. The calculations are based upon
the general configuration interaction code CIV3 of Hibbert. Calculated
values are compared with experimental and other theoretical results
where some unpublished energy values and oscillator strengths are
reported.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Atomic Data.
Abstract
-
Energy levels and transition probabilities for transitions between
computed levels are reported for the Al-like ions (Z = 33- 35). The
results have been calculated using the multiconfiguration Hartree–Fock (MCHF)
method with Breit–Pauli relativistic correction (C.F.Fischer's ATSP
computer package). Data for selected allowed (E1) and some forbidden
(M1, E2, M2, E3) transitions are reported.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Atomic Data.
Abstract
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In the present paper, an estimation to study effects of the relaxation
times and magnetic field on the reaction of P-wave and SV-wave on the
boundary of a half-space of homogeneous, isotropic thermoelastic medium
taking into our consideration the boundary is stress-free as well as
insulated or isothermal. GL model of generalized thermoelasticity has
been applied to obtain the amplitudes of the Reaction coefficients.
Lame's potentials are used in the two dimensions oxz that tend to
separate the governing equations into three equations that sought in
harmonic travelling form. We introduce the equations of the velocity of
P-wave, T-waveand SV-wave. The boundary conditions for mechanical and
Maxwell's stresses and thermal insulated or isothermal are applied to
determine the reaction coefficients for P-wave, T-wave and SV wave. Some
new aspects are obtained of the reaction coefficients and displayed
graphically and the new conclusions are presented. Effects of relaxation
times and magnetic fields on the reaction of generalized thermoelastic
waves are noticed and depicted graphically. Finally, it is shown that,
under some conditions and some modifications, the previous results [25]
are special cases from our results.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Magnetic Field, Reaction, Half space, P-wave, T-wave, SV-wave,
Relaxation times, Isothermal boundaries, Insulated surface.
Abstract
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The destroying of rainforests can warm the climate even more than the
doubling of CO2 concentration can do. The temperature close to the
surface of the earth can change due to the change of the feedback or the
amount of water in the atmosphere, without any forcing or change in the
concentration of CO2 as well as other greenhouse gases. This paper
derives physically the sensitivity and the response time of the climate
due to radiative forcing and a change in feedback. During the last
century the temperature increase consisted of change in solar activity
(0.47°C), destruction of rainforests (about 0.3°C), increase of the
concentrations of the greenhouse gases (about 0.1°C) and increase of
aerosols (about -0.06°C). About one half of the temperature increase was
anthropogenic.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Climate Change, Climate Sensitivity, Climate Response Time.
Abstract
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In this paper, we study the radial vibrations of a poroelastic hollow cylinder with convective boundary conditions. Biot’s theory is employed for wave propagation in a porous solid, the frequency equation for radial vibration of a poroelastic cylinder is obtained includes initial stress as a convective boundary condition. The frequency equation has been derived in the form of a determinant form involving Bessel functions. The root of the frequency frequency equation determines the circular frequency. Special case from this study is investigated if the initial stress is neglected. The numerical computations of the frequency equations for the radial vibrations of a poroelastic cylinder is obtained and are illustrated graphically. It is found the frequency equation of the waves has been affected by the poroelasticity and the initial stress which indicated that their very pronounced on the natural frequency.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Natural frequencies, poroelastic hollow cylinder, initial stress, convective.
Abstract
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The aim of this work has been to obtain and characterize transparent conducting thin films of zinc oxide. This work takes into consideration that the preparation technique used should be suitable for local technical conditions. For this purpose, a spray pyrolysis (SP) was constructed. SP is a simple and inexpensive technique. Zinc chloride hydrate was used as starting material and our films were deposited onto glass substrates. Structural, optical and electrical properties of ZnO thin films, were determined. This study relates to the effects of deposition parameters such as: molarity, deposition time and substrate temperature on the quality of films. The prepared films were uniform and well adherent to the substrates. XRD analysis of the films revealed that all the films were microcrystalline having hexagonal wurtzite-type crystal structure with strong orientation along (002) plane which became enhanced by the increase in temperature. An optical transmittance of 80% in the visible range was measured. The estimated band gap energy of ZnO films which have a thickness between 0.3 and 0.5 µm from optical absorption data was 3.3 eV. The room temperature conductivity is of the order of 10-1 (Ω
cm)-1.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Spray pyrolysis, Zinc Oxide, thin films, Semiconductor, Characterization.
Abstract
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In this work, the reflection and transmission phenomena of thermoelastic
plane waves at an imperfect interface between two dissimilar
thermoelastic solid half-spaces with magnetic field has been discussed.
Green and Naghdi (1993) as a thermoelastic theory without energy
dissipation is devoted to study the problem. The amplitude ratios of
various reflected and refracted waves are investigated for an imperfect
boundary. Some special cases of the problem are discussed. The amplitude
ratios are also deduced at the interface of two semi-infinite media (i)
Elastic/magneto-thermoelastic without energy dissipation, (ii) Thermal
conducting liquid/thermoelastic without energy dissipation, (iii)
Non-viscous fluid/thermoelastic without energy dissipation, (iv)Thermal
conducting liquid/thermal conducting Liquid and (v) Elastic/Elastic. It
is found that the amplitude ratios of various reflected and refracted
waves are affected by the stiffness, magnetic field and thermal
properties of the media. The amplitude ratios of reflected waves are
also deduced for a special case of stress-free boundary. Finally, the
results obtained are calculated numerically and displayed graphically.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
Magneto-Thermoelasticity, Thermal Stress, Energy Dissipation,
Reflection, Transmission, GN Model.
Abstract
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This paper uses optical design software CODE V to design optic non-spherical Fresnel len and using non-optic simulation software LightTools to conduct light ray tracing and analysis of light energy. Optic software has optimization function to design the best optic non-spherical Fresnel lens; through this research analysis and simulation evaluation of optical systems, design miscalculations and risks of failure can be lowered as well as verifying laboratory results. Research and development are also performed on optic Fresnel lenses made with a hybrid material, which involves using molding methods to combine glass and silicon. During experiments, it was discovered that Fresnel lenses made with white glass and silicon have an average penetration of 92% within infrared wavelength perimeters; those made with PC materials had average penetration of only 76%. The lifespan of silicon Fresnel lenses are also much longer than other plastic materials. Therefore the application of silicon materials on converging-type solar power collecting systems would likely become the best option in the future.
Copyright © 2011 Praise Worthy Prize S.r.l. -
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Keywords:
converging-type solar power battery, Fresnel lens, silicon.
Abstract
-
A fluid approach is used to investigate a multi-component magnetized
plasma sheath which consists of electrons, dust grains and two species
of positive ions. The effect of the presence of second positive ion
species on the sheath characteristics is examined. The calculated
results show that the second ion species affects some parameters of the
plasma sheath such as the spatial distributions of the electric
potential, velocity and density of plasma particles. In addition, the
ion temperature and the density ratio of dusts to lighter ions at the
sheath edge on the sheath characteristics are discussed.
Copyright © 2011 Praise Worthy Prize S.r.l. -
All rights reserved
Keywords:
Dust Grains, Magnetic Field, Ion Temperature, Multi-Component
Plasma.
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