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Development and Optimization of Laser-Induced Breakdown Spectroscopy (LIBS) for Quantification of Carbon in Steel within UV/Visible Region
Mohamed A. Khater,
Mohammed M. Babatin,
Ali M. Eid,
Abdulaziz S. Alaamer
Issue:
Volume 2, Issue 6, November 2014
Pages:
113-117
Received:
26 October 2014
Accepted:
4 November 2014
Published:
10 November 2014
DOI:
10.11648/j.ajpa.20140206.11
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Abstract: A simple bench-top laser-induced breakdown spectroscopy (LIBS) technique is investigated for the rapid detection of sufficient amount of the light element carbon. The plasma investigated was generated by focusing the fundamental radiation at 1064 nm of Nd:YAG laser onto low alloy steel target. The radiation emitted from the plasma was dispersed and recorded by an echelle spectrograph combined with a time-gated EMCCD detection system. Based on an extensive survey procedure, a well-resolved relatively-intense neutral carbon spectral line at 396.14 nm was selected, verified and used in all measurements. In addition, optimization of the main experimental parameters, namely laser energy and delay-time for integration of the detector was carried out. Furthermore, the analytical calibration curve for carbon, using a series of low-alloy steel standards, was constructed and corresponding analytical figures of merit were evaluated.
Abstract: A simple bench-top laser-induced breakdown spectroscopy (LIBS) technique is investigated for the rapid detection of sufficient amount of the light element carbon. The plasma investigated was generated by focusing the fundamental radiation at 1064 nm of Nd:YAG laser onto low alloy steel target. The radiation emitted from the plasma was dispersed and...
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The Ball of Lightning Structure and Creation
Issue:
Volume 2, Issue 6, November 2014
Pages:
118-120
Received:
8 October 2014
Accepted:
28 November 2014
Published:
2 December 2014
DOI:
10.11648/j.ajpa.20140206.12
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Abstract: By studying a drop of water reaction and behavior on a hot surface while gradually increasing the surface temperature, and by making more experiments on the Leidenfrost Effect, the author explained the ball lightning structure and its dynamic release of energy through one single system of physics. The dynamic action starts when a drop of water is entered in an environment of 10000 ºC temperature. The high temperature causes the water drop to form a rotating sphere which has a constant temperature of 99 ºC. The sphere of water transforms all extra thermal energy affecting it’s constant temperature to gravity (experimental discovery), and while water sphere is rotating its center, its radius crosses the gravity field. So according to Fleming’s left hand rule, an electrical current in the water mass will be created. This electrical current will split the water molecule to oxygen and hydrogen which will burn outside the water sphere to create the needed thermo energy to continue the rotation of the water sphere and so on the production of gravity, thermal energy, electromagnetic field and light. Jaber’s law gives a new understanding of gravity and compares between stars and ball of lightning, and solves ambiguous matters in our understanding of stars, planets and moons behavior. The second step of understanding ball lightning structure led the author to build his theories, which explained the relation between gravity and temperature of objects, tying his theories with experimental discovery of repulsion between gravity and heat.
Abstract: By studying a drop of water reaction and behavior on a hot surface while gradually increasing the surface temperature, and by making more experiments on the Leidenfrost Effect, the author explained the ball lightning structure and its dynamic release of energy through one single system of physics. The dynamic action starts when a drop of water is e...
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Travelling Waves Solution of the Unsteady Problem of Binary Gas Mixture Affected by a Nonlinear Thermal Radiation Field
Taha Zakaraia Abdel Wahid
Issue:
Volume 2, Issue 6, November 2014
Pages:
121-134
Received:
10 November 2014
Accepted:
26 November 2014
Published:
5 December 2014
DOI:
10.11648/j.ajpa.20140206.13
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Abstract: In the present study, a development of the paper [Can. J. of Phy., 2012, 90(2): 137-149] is introduced. The non-stationary BGK (Bhatnager- Gross- Krook) model of the Boltzmann nonlinear partial differential equations for a rarefied gas mixture affected by nonlinear thermal radiation field, for the first time, are solved instead of the stationary equations. The travelling wave solution method is used to get the exact solution of the nonlinear partial differential equations. These equations were produced from applying the moment method to the unsteady Boltzmann equation. Now, nonlinear partial differential equations should be solved in place of nonlinear ordinary differential equations, which represent an arduous task. The unsteady solution gives the problem a great generality and more applications. The new problem is investigated to follow the behavior of the macroscopic properties of the gas mixture such as the temperature and concentration. They are substituted into the corresponding two stream Maxiwallian distribution functions permitting us to investigate the non-equilibrium thermodynamic properties of the system (gas mixture + the heated plate). The entropy, entropy flux, entropy production, thermodynamic forces, kinetic coefficients are obtained for the mixture. The verification of the Boltzmann H-theorem, Le Chatelier principle, the second law of thermodynamic and the celebrated Onsager’s reciprocity relation for the system, are investigated. The ratios between the different contributions of the internal energy changes based upon the total derivatives of the extensive parameters are estimated via the Gibbs formula. The results are applied to the Argon-Neon binary gas mixture, for various values of both of the molar fraction parameters and radiation field intensity. Graphics illustrating the calculated variables are drawn to predict their behavior and the results are discussed.
Abstract: In the present study, a development of the paper [Can. J. of Phy., 2012, 90(2): 137-149] is introduced. The non-stationary BGK (Bhatnager- Gross- Krook) model of the Boltzmann nonlinear partial differential equations for a rarefied gas mixture affected by nonlinear thermal radiation field, for the first time, are solved instead of the stationary eq...
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Acoustical Phonons Transport through a Stepped Quantum Wire
Issue:
Volume 2, Issue 6, November 2014
Pages:
135-144
Received:
29 November 2014
Accepted:
4 December 2014
Published:
16 December 2014
DOI:
10.11648/j.ajpa.20140206.14
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Abstract: This work presents a theoretical approach for the study of phonon dynamics and scattering properties of an infinite linear atomic chain perturbed by a mono atomic step. The coherent transmittance scattering cross-sections for incident phonons on the atomic waveguide structure are calculated using the Landauer-Buttiker electron scattering description and the matching method formalism with the nearest and next nearest neighbour interactions. Numerical results for different configurations yield an understanding of the chain dynamical properties and the effects on phonon transmittance due to incoming phonons. The reflectance and transmittance coefficients show spectral characteristic features depending on the cut-off frequencies for the propagating phonons. They illustrate the occurrence of Fano resonances in the scattering spectra that result from degeneracy of step localized modes and propagating continuum modes due to the breakdown of the translation symmetry in the propagating direction. Furthermore, the interferences between diffused and reflected waves in the step regions generate Fabry-Pérot oscillations whose number is determined by the distance between steps and the number of terraces.
Abstract: This work presents a theoretical approach for the study of phonon dynamics and scattering properties of an infinite linear atomic chain perturbed by a mono atomic step. The coherent transmittance scattering cross-sections for incident phonons on the atomic waveguide structure are calculated using the Landauer-Buttiker electron scattering descriptio...
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Comparison of Some Human Tissues and Some Commonly Used Thermoluminescent Dosimeters for Photon Energy Absorption
Adem Un,
Mümine Un,
Ibrahim Han
Issue:
Volume 2, Issue 6, November 2014
Pages:
145-149
Received:
30 November 2014
Accepted:
5 December 2014
Published:
16 December 2014
DOI:
10.11648/j.ajpa.20140206.15
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Abstract: Mass energy absorption coefficients and effective atomic numbers for photon energy absorption, ZPEAeff have been calculated in the energy range from 1 keV to 20 MeV for human tissues, Adipose Tissue, Blood Whole, Bone Cortical, Brain Grey/White Matter, Breast Tissue, Eye Lens, Lung Tissue, Muscle Skeletal, Ovary, Testis, Soft Tissue. Mass energy absorption coefficients and effective atomic numbers for photon energy absorption have also been calculated for commonly used thermoluminescent dosimeters,TLD, in the energy range from 1 keV to 20 MeV. The energy dependence of the mass energy absorption of human tissues and TL dosimeters are shown graphically. The tissue equivalency of TLDs is investigated. The effects of the elemental composition on effective atomic numbers for photon energy absorption and the tissue equivalency of TLDs are discussed.
Abstract: Mass energy absorption coefficients and effective atomic numbers for photon energy absorption, ZPEAeff have been calculated in the energy range from 1 keV to 20 MeV for human tissues, Adipose Tissue, Blood Whole, Bone Cortical, Brain Grey/White Matter, Breast Tissue, Eye Lens, Lung Tissue, Muscle Skeletal, Ovary, Testis, Soft Tissue. Mass energy ab...
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Methods for Determination of the Optical Constants of the Substance BiTe-BiSe
Issue:
Volume 2, Issue 6, November 2014
Pages:
150-155
Received:
29 November 2014
Accepted:
15 December 2014
Published:
22 December 2014
DOI:
10.11648/j.ajpa.20140206.16
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Abstract: On the basis of the interference fringes in the transparency and reflection spectra of the free film or a film on the substrate when the substrate and the film material does not absorb light, can be determined by one of the optical constants of the material at a blank principal refractive index, if the film thickness is known.
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ZnRE (RE=La and Ce) Intermetallics: A First-Principles Investigation
Afroj Ahmed Khan,
Vipul Srivastava,
Mathrubutham Rajagopalan,
Sankar Prasad Sanyal
Issue:
Volume 2, Issue 6, November 2014
Pages:
156-161
Received:
29 November 2014
Accepted:
22 December 2014
Published:
31 December 2014
DOI:
10.11648/j.ajpa.20140206.17
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Abstract: ZnRE (RE= La and Ce) intermetallics were investigated with respect to their electronic properties using first principles tight binding linear muffin tin orbital method. Electronic band structures, partial and total densities of states have been derived. The band structures show metallic character; the conductivity is mostly governed by Zn-3d and RE-4f states. The thermodynamical properties like Debye temperature and Grüneisen constant are estimated using Debye-Grüneisen (DG) model. The value of Debye temperature is calculated to be 193 K for ZnLa and 191 K for ZnCe. The Co-efficient of electronic heat capacity is also estimated and discussed. It is found to be 4.97 mJ/K2mol for ZnLa and 29.29 mJ/K2mol for ZnCe in calculations. The estimation of cohesive energy revealed the bond strength between Zn and RE. These estimated values are found to be 753.6 KJ/mol and 812.5 KJ/mol for ZnLa and ZnCe, respectively.
Abstract: ZnRE (RE= La and Ce) intermetallics were investigated with respect to their electronic properties using first principles tight binding linear muffin tin orbital method. Electronic band structures, partial and total densities of states have been derived. The band structures show metallic character; the conductivity is mostly governed by Zn-3d and RE...
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Optical Band Gap and Physical Properties of Nd3+ Doped Cadmium Borate Glasses
Yogesh Kumar Sharma,
Rajendra Prasad Joshi,
Priyanka Goyal
Issue:
Volume 2, Issue 6, November 2014
Pages:
162-166
Received:
6 December 2014
Accepted:
23 December 2014
Published:
6 January 2015
DOI:
10.11648/j.ajpa.20140206.18
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Abstract: Nd3+- doped cadmium borate glasses were prepared and characterized optically. The oscillator strengths and Judd-Ofelt parameters for the glass containing 0.1, 0.3 and 0.5 wt% of Nd2¬O3 were computed. Density, refractive index and optical absorption spectra were measured. The values of Judd- Ofelt parameters suggested an increase in the degree of asymmetry the local ligand field at Nd3+ sites. The optical band gap energy and physical parameters was calculated for all glass samples. It was found that with increasing the concentration of Nd2O3 contents, the values of the optical band gap energy decrease.
Abstract: Nd3+- doped cadmium borate glasses were prepared and characterized optically. The oscillator strengths and Judd-Ofelt parameters for the glass containing 0.1, 0.3 and 0.5 wt% of Nd2¬O3 were computed. Density, refractive index and optical absorption spectra were measured. The values of Judd- Ofelt parameters suggested an increase in the degree of as...
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