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2009

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Energy Levels Of The 6p_{3/2}Ns, Nd, Ng Autoionizing Series Of Pb I, Chao Zhou, Liang Liang, Ling Zhang Jan 2009

Energy Levels Of The 6p_{3/2}Ns, Nd, Ng Autoionizing Series Of Pb I, Chao Zhou, Liang Liang, Ling Zhang

Turkish Journal of Physics

Based on the weakest bound electron potential model (WBEPM) theory, six energy levels of the autoionizing Rydberg series 6pns 3/2[3/2]_1 (n = 15-25), 6pns 3/2[3/2]_2 (n = 15-25), 6pnd 3/2[3/2]_1 (n = 13-25), 6pnd 3/2[5/2]_3 (n = 13-25), 6pnd 3/2[7/2]_3 (n = 14-25) and 6png 3/2[5/2]_2 (n = 5-25) of Pb I are calculated. Foreign level perturbation corrections are taken into account in calculations of four series among them. The theoretical calculated results are in good agreement with the known experimental data, and some energies without experimental values are predicted.


Superconducting State Parameters Of Al-Li Binary Alloys, Aditya M. Vora Jan 2009

Superconducting State Parameters Of Al-Li Binary Alloys, Aditya M. Vora

Turkish Journal of Physics

Theoretical computation of superconducting state parameters (SSP) viz. electron-phonon coupling strength \lambda , Coulomb pseudopotential \mu^* , transition temperature T_C , isotope effect exponent \alpha and effective interaction strength N_o V of face centered cubic Al_{1-C} Li_C binary alloys have been made extensively in the present work using a model potential formalism for the first time. A considerable influence of various exchange and correlation functions on \lambda and \mu^* is found from the present study. The present results of the SSP are found in qualitative agreement with the available experimental data wherever exist.


Cover And Contents Jan 2009

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Combined Analysis Of Solar Neutrino Data Within The Rsfp Framework Together With New Kamland Data, Deni̇z Yilmaz Jan 2009

Combined Analysis Of Solar Neutrino Data Within The Rsfp Framework Together With New Kamland Data, Deni̇z Yilmaz

Turkish Journal of Physics

A combined analysis of solar neutrino data together with the new KamLAND data is presented in the RSFP framework. It is investigated how the allowed regions are effected from the new KamLAND data at different \mu B values. Limits on \mu B value is found at the different confidence level intervals.


Production Of Ybco Superconductor Sample By Powder-In-Tube Method (Pitm); And Effect Of Cd And Ga Doping On The System, Serkan Alagöz Jan 2009

Production Of Ybco Superconductor Sample By Powder-In-Tube Method (Pitm); And Effect Of Cd And Ga Doping On The System, Serkan Alagöz

Turkish Journal of Physics

In this study, YBa_2Cu_3O_{7-\delta} and Y_{0.5}X_{0.5}Ba_2Cu_3O_{7-\delta} (x = Ga, Cd) compounds are produced by Powder-In-Tube Method and electrical and physical characteristics of those samples were investigated. Following 3, 5 and 9 tons pressure applied to three sample groups (YBa_2Cu_3O_{7-\delta}, Y_{0.5}Cd_{0.5}Ba_2Cu_3O_{7-\delta}, Y_{0.5}Ga_{0.5}Ba_2Cu_3O_{7-\delta}), samples were examined via X-Ray diffraction, resistivity and SEM measurement. Considerable changes in Crystallographic properties of the YBCO samples, produced by using Powder-In-Tube Method for different pressure values, were observed. Under different magnetic fields conditions, resistance of the YBCO samples was measured and it was seen that samples had very pure and homogenous structure. Ga doping into YBCO composition …


Asphericity In The Fermi Surface Of D And F-Shell Metals, J. K. Baria, A. R. Jani Jan 2009

Asphericity In The Fermi Surface Of D And F-Shell Metals, J. K. Baria, A. R. Jani

Turkish Journal of Physics

Recently proposed pseudopotential has been used to calculate asphericity in the Fermi surface of d and f-shell metals along the three symmetry directions [100], [110] and [111]. The parameter of the potential has been determined by zero pressure condition and the exchange and correlation function due to Taylor has been incorporated. The present results are in good agreement with experimental findings for Cu, Ag, Au and Pd; while for other d and f- shell metals we could not found sufficient theoretical as well as experimental data for the asphericity in the Fermi Surface in order to workout a quantitative comparison. …


Electrical Characterization And Relaxation Behavior Of Lithium-Indium-Phosphate Glasses Via Impedance Spectroscopy, M. V. N. V. D. Sharma, A. V. Sarma, R. Balaji Rao Jan 2009

Electrical Characterization And Relaxation Behavior Of Lithium-Indium-Phosphate Glasses Via Impedance Spectroscopy, M. V. N. V. D. Sharma, A. V. Sarma, R. Balaji Rao

Turkish Journal of Physics

Phosphate glasses with various compositions of lithium oxide and indium oxide were synthesized by melt quenching technique. The glass forming ability parameter K_{gl} was characterized by differential thermal analysis. The electrical measurements for all the glass samples were carried out in the frequency range of 10 Hz to 10^{6} Hz and at a temperature range of 393-513 K by the Impedance spectroscopy. Frequency dependent conductivity follows the power law. The ac conductivity increases with temperature following the Arrhenius law. Master curve in the scaling analysis suggesting the temperature independent conduction relaxation mechanism.


Generation Of Ultrafast Bright And Dark Pulse On Silicon Chip With Integrated Mach-Zehnder Interferometer Configuration, Jianwei Wu, Fengguang Luo Jan 2009

Generation Of Ultrafast Bright And Dark Pulse On Silicon Chip With Integrated Mach-Zehnder Interferometer Configuration, Jianwei Wu, Fengguang Luo

Turkish Journal of Physics

In this paper we propose and simulate ultrafast femtosecond bright and dark pulses, obtained simultaneously at the same center wavelength, based on silicon-on-insulator (SOI) waveguides in Mach-Zehnder interferometer (MZI) configuration; the ultrafast pulsed pump is injected into one MZI's arm and a continuous wave component (CW) is divided equally into the two MZI arms. Numerical results show that properties of the generated bright and dark pulses are strongly dependent on the launching optical powers of both the pump pulse and CW carriers, and on the waveguide length.


Unsteady Free Convection Flow With Thermal Radiation Past A Vertical Porous Plate With Newtonian Heating, Promise Mebine, Emmanuel Munakurogha Adigio Jan 2009

Unsteady Free Convection Flow With Thermal Radiation Past A Vertical Porous Plate With Newtonian Heating, Promise Mebine, Emmanuel Munakurogha Adigio

Turkish Journal of Physics

This paper considers exact solutions of unsteady free convection flow with thermal radiation past a vertical porous plate with Newtonian heating. The technique of Laplace transform was employed in deriving the solutions to the governing flow and energy equations. A parametric study of all parameters involved was conducted, and a representative set of results showing the effect of the radiation parameter N, the ratio of uniform suction to characteristic velocity parameter R, and the free convection parameter Gr on the velocity and temperature are illustrated graphically. The skin friction or shear and heat flux are discussed quantitatively. It is evident …


Cover And Contents Jan 2009

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel Jan 2009

Electric Multipole Moments Of Some Diatomic Molecules Molecules, M. Özgür Sezer, Ayhan Özmen, Hüseyi̇n Yüksel

Turkish Journal of Physics

Molecular Electric Multipole Moment (MEMM) integrals have been derived for diatomic molecular systems, and then some lower multipole moments as dipole moments and quadrupole moments have been calculated for some diatomic molecules. The calculations have been performed by using our analytical formula over Slater-Type orbitals (STOs) with Cade and Huo's basis sets and the GAMESS program package working with Gaussian-Type basis sets (GTOs). The expressions which involve factorials are given in terms of binomial coefficients in order to speed up calculations. The results have been obtained in agreement with data found in the literature.


Composition Dependent Of Dielectric Properties In Se_{100-X}Pb_X Glassy Alloys, Jyoti Sharma, Santosh Kumar Jan 2009

Composition Dependent Of Dielectric Properties In Se_{100-X}Pb_X Glassy Alloys, Jyoti Sharma, Santosh Kumar

Turkish Journal of Physics

In this paper we report the composition dependent of dielectric properties in Se_{100-x}Pb_x (x = 0, 2, 4, 6 and 10) glassy alloys. The temperature and frequency dependence of the dielectric constants and the dielectric losses in the above glassy systems in the frequency range 1 kHz-5 MHz and temperature range 300-340 K have been measured. It has been found that dielectric constant and the dielectric loss both are highly dependent on frequency and temperature and also found to be increased with increasing concentration of Pb in pure amorphous Se. The results have been interpreted in terms of increase in …


The Electrical Conduction Mechanisms And Thermoelectric Power Of Snse Single Crystals, M. M. Nassary Jan 2009

The Electrical Conduction Mechanisms And Thermoelectric Power Of Snse Single Crystals, M. M. Nassary

Turkish Journal of Physics

Single crystals of SnSe were prepared in our laboratory by a special modified Bridgman technique. Measurements of the electrical conductivity and Hall effect between 141 K and 553 K were carried out on SnSe sample in two crystallographic directions. The investigated sample was found to be of p-type conductivity. The Hall mobilities parallel and perpendicular to layers plane at room temperature, were 7835.9 cm^2/ V \cdots and 7274.7 cm^2/ V.s, respectively. The free carrier concentration P = 3.52 \times 10^{12} cm^{-3} at room temperature. Also, the thermoelectric power (TEP) was investigated in the temperature range from 176 to 553 K. …


Behavior Of Transition Amplitude And Evolution Of The Energy Of Quantum Kicked Rotator, Abdolrasoul Gharaati Jan 2009

Behavior Of Transition Amplitude And Evolution Of The Energy Of Quantum Kicked Rotator, Abdolrasoul Gharaati

Turkish Journal of Physics

I give certain analytical properties of quantum kicked rotators, both theoretic and observed from computation. I give an expression for the wave function between two successive impulses. An element of the transition matrix, the matrix that takes the wave function from one impulse to another, exponentially falls away from the main diagonal. The decay parameter is given for a few special cases of a periodic potential. Finally, the transition matrix is used to derive the time evolution of the energy for periodic cases and for fundamental resonances. The empirical expressions of Dorizzi et al. are compatible with our analytical results.


Study Of Second-Class Currents Effects On Polarization Characteristics In Quasi-Elastic Neutrino (Anti-Neutrino) Scattering By Nuclei, Adamou Ousmane Manga, Almoustapha Aboubacar Jan 2009

Study Of Second-Class Currents Effects On Polarization Characteristics In Quasi-Elastic Neutrino (Anti-Neutrino) Scattering By Nuclei, Adamou Ousmane Manga, Almoustapha Aboubacar

Turkish Journal of Physics

The differential cross section of quasi-elastic neutrino scattering by nuclei is computed. The numerical analysis of energy dependence of the spin asymmetry, the angular electron-neutrino (e\nu) correlation and the charge asymmetry coefficients shows that the relative contribution of the second-class current (SCC) tensor form factor can reach some tens of percents in the case of particular values of final nuclei alignment and polarization.


Cover And Contents Jan 2009

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Thermoelectric Power And Low-Field Electron Mobility In Al_Xga_{1-X}N Lattice-Matched To Gan, H. Arabshahi Jan 2009

Thermoelectric Power And Low-Field Electron Mobility In Al_Xga_{1-X}N Lattice-Matched To Gan, H. Arabshahi

Turkish Journal of Physics

The results of thermoelectric power and electron drift mobility in Al_xGa_{1-x}N lattice-matched to GaN are calculated for different temperatures, free-electron concentrations and compositions. The two-mode nature of the polar optic phonons is considered jointly with deformation potential acoustic, piezoelectric, alloy and ionized-impurity scattering. Band non-parabolicity, admixture of p functions, arbitrary degeneracy of the electron distribution and the screening effects of free carriers on the scattering probabilities are incorporated. The Boltzmann equation is solved by an iterative technique using the currently established values of the material parameters. The iterative results are in fair agreement with other recent calculations obtained using the …


Growth And Microindentation Analysis Of Pure And Doped Sb_2se_3 Crystals, K. A. Chandrasekharan, A. G. Kunjomana Jan 2009

Growth And Microindentation Analysis Of Pure And Doped Sb_2se_3 Crystals, K. A. Chandrasekharan, A. G. Kunjomana

Turkish Journal of Physics

Pure and doped antimony selenide (Sb_2Se_3, Sb_2Se_{2.8}Te_{0.2}, and Sb_2Se_{2.6}Te_{0.4}) crystals have been grown from melt by the Bridgman Stockbarger method. X-ray powder diffraction analysis was carried out to determine the lattice parameters of the grown samples. The morphology of cleavage planes was observed using SEM. Energy dispersive analysis by X-rays (EDAX) was done to find out the chemical composition of the grown samples. Correlation of microhardness with other mechanical characteristics such as toughness, brittleness, and yield strength, has been investigated. The effects of Te doping on the mechanical behaviour and energy gap were also studied on the cleavage faces.


Advance (Fall 2009), Georgia Southern Division Of Continuing And Professional Education Jan 2009

Advance (Fall 2009), Georgia Southern Division Of Continuing And Professional Education

Division of Continuing & Professional Education

No abstract provided.


A Study Of The Beneficial Role Of Thiol Antioxidant Supplementation In Various Forms Of Glutathione Deficiency, Linu Sara Abraham Jan 2009

A Study Of The Beneficial Role Of Thiol Antioxidant Supplementation In Various Forms Of Glutathione Deficiency, Linu Sara Abraham

Doctoral Dissertations

"Oxidative stress plays a major role in the pathology of numerous disorders afflicting humans, ranging from neurodegenerative diseases, to cancer, and heavy metal toxicity. Scientists are on the constant lookout for new and better antioxidants that have the ability to slow, if not stop the harmful degenerative effects of free radicals in oxidative stress related disorders. Both synthetic and naturally occurring compounds are being constantly screened for their antioxidant properties. This study attempted to evaluate the abilities of a thiol antioxidant, N-Acetylcysteine amide (NACA), to protect cells from the harmful effects of glutathione depletion in two different models of oxidative …


Anti Wetting Additives For Aluminosilicate Refractories In Molten Aluminum Contact Applications, Devdutt Pramod Shukla Jan 2009

Anti Wetting Additives For Aluminosilicate Refractories In Molten Aluminum Contact Applications, Devdutt Pramod Shukla

Doctoral Dissertations

"Aluminosilicate based refractories are widely used in furnace installations for melting aluminum because they are inexpensive, readily available and generally exhibit the properties desired from a refractory material. However, they face severe corrosion and degradation issues due to the extremely reducing nature of molten aluminum alloys. Isothermal static cup testing is widely used as a tool to evaluate the performance of refractories against penetration by molten aluminum alloys. Various testing methods were reviewed and an upgraded static cup test was recommended. Commercially available aluminosilicate refractories were tested using this method and their results were studied in order to understand the …


Applications Of Sensor Arrays In Acoustic And Seismic Signal Processing, Peng Xie Jan 2009

Applications Of Sensor Arrays In Acoustic And Seismic Signal Processing, Peng Xie

Doctoral Dissertations

"This work investigates the applications of sensor arrays in the areas of acoustic and seismic signal processing. It comprises three papers.

The first paper explores the problem of blind source separation (BSS) for convolutive acoustic signals. It concentrates on the well known permutation and amplitude problems in frequency-domain BSS and proposes a new hybrid approach to solve them. This approach connects the separation processes across all frequency bins, and relies on a novel permutation control unit. This framework could greatly reduce computational load and improve separation performance. Synthesized and real-world experiments demonstrate its efficiency.

The second paper investigates a new …


Fundamentals Of Friction Stir Spot Welding, Harsha Badarinarayan Jan 2009

Fundamentals Of Friction Stir Spot Welding, Harsha Badarinarayan

Doctoral Dissertations

"The recent spike in energy costs has been a major contributor to propel the use of light weight alloys in the transportation industry. In particular, the automotive industry sees benefit in using light weight alloys to increase fuel efficiency and enhance performance. In this context, light weight design by replacing steel with Al and/or Mg alloys have been considered as promising initiatives. The joining of structures made of light weight alloys is therefore very important and calls for more attention. Friction Stir Spot Welding (FSSW) is an evolving technique that offers several advantages over conventional joining processes.

The fundamentals aspects …


Systematic Functional And Object-Oriented Product Design Frameworks, Jen-Chi Wu Jan 2009

Systematic Functional And Object-Oriented Product Design Frameworks, Jen-Chi Wu

Doctoral Dissertations

"The existing co-design methods of mechatronic products focus on co-design of mechanical and electronic components or co-design of computer hardware and software components. There exist no effective co-design methods for mechanical, electronic and software components at the concept design stage. The research objective of this dissertation work is to develop more effective systematic product design approaches for co-design of mechatronic products. Three innovative functional and object-oriented integrated design frameworks and one virtual prototyping application, which leverages on these three design frameworks, have been developed for co-design of mechatronic products. The three frameworks are: I) Hierarchical Object-Oriented Functional Modeling Framework, 2) …


The Role Of Stochastic Resonance And Physical Constraints In The Evolution Of Foraging Strategy, Nathan Daniel Dees Jan 2009

The Role Of Stochastic Resonance And Physical Constraints In The Evolution Of Foraging Strategy, Nathan Daniel Dees

Doctoral Dissertations

"This work represents a detailed study of the optimization of this process: foraging within a single, finite food patch for a limited amount of time. The work is an example of the computational algorithms of statistical physics being applied to the ecological field of foraging behavior. The analysis begins with an examination of the probability distributions observed in the movement parameters of the zooplankton, Daphnia. While foraging, these small aquatic organisms stochastically choose movement parameters with particular levels of variation, or noise, which are similar across several species. Here, related simulations consistently show that these noise levels may be adjusted …


F₂-Isoprostanes Study After Exposure To Selected Nanoparticles By Liquid Chromatography/Tandem Mass Spectrometry And Investigation Of Nanoparticles On The Cytotoxicity Effect Of Arsenic In Vitro, Xiaoqian Liu Jan 2009

F₂-Isoprostanes Study After Exposure To Selected Nanoparticles By Liquid Chromatography/Tandem Mass Spectrometry And Investigation Of Nanoparticles On The Cytotoxicity Effect Of Arsenic In Vitro, Xiaoqian Liu

Doctoral Dissertations

"Nanopartices as a new class of materials found their applications in industry, aerospace, clinical diagnosis and cancer therapy. Recently, the health effects of nanoparticles have caused people great concerns. This dissertation studies the mechanisms of nanoparticle cytotoxicity in human lung epithelial cells (A549). F₂-isoprostanes are novel reliable biomarkers for lipid peroxidation. In the first part of this work, total free F₂-isoprostanes were quantified by high performance liquid chromatography/mass spectrometry followed by the exposure of SiO₂ (15 nm), CeO₂ (20 nm), Fe₂O₃ (30 nm), and ZnO (70 nm) nanoparticles for 24 hours. For the first time, the results showed that F₂-isoprostanes …


Interference Effects Due To Projective-Target Nucleus Scattering In Single Ionization Of Molecular Hydrogen By 75 Kev Proton Impact, Jason S. Alexander Jan 2009

Interference Effects Due To Projective-Target Nucleus Scattering In Single Ionization Of Molecular Hydrogen By 75 Kev Proton Impact, Jason S. Alexander

Doctoral Dissertations

"Doubly-differential cross-sections for the single ionization of molecular hydrogen by 75 keV proton impact have been measured as a function of the projectile scattering angle and energy loss and compared to available theoretical models. Interference structures are directly observed in the scattering angular dependence of the DDCS. The phase angle appears to be most sensitive to the projectile angle but not as sensitive to the electron energy, suggesting that the projectile - target nucleus interaction plays a central role in the interference. The large-angle structures disappear at electron speeds near the projectile speed. This may be due to a focusing …


Advanced Control Techniques For Doubly Fed Induction Generator-Based Wind Turbine Converters To Improve Low Voltage Ride-Through During System Imbalances, Murali M. Baggu Jan 2009

Advanced Control Techniques For Doubly Fed Induction Generator-Based Wind Turbine Converters To Improve Low Voltage Ride-Through During System Imbalances, Murali M. Baggu

Doctoral Dissertations

A doubly-fed induction generator (DFIG) applied to wind power generation is under study for low voltage ride-through application during system disturbances. Conventional dq axis current control using voltage source converters for both the grid side and the rotor side of the DFIG are analyzed and simulated. DFIG operation is investigated under balanced and unbalanced system disturbances. A conventional d-axis and q-axis control applied to a voltage source converter (VSC) during a system imbalance exhibits oscillations in the stiff DC link voltage as well as in the real and reactive powers of the converter. Multiple advanced control methods are explored and …


Wind Power Applications To Groundwater Remediation, Ronald E. Gallagher Jan 2009

Wind Power Applications To Groundwater Remediation, Ronald E. Gallagher

Doctoral Dissertations

"The use of renewable energy systems to power groundwater remediation systems seems like an inherently good idea because of potential cost savings and environmental benefits associated with reduced greenhouse gas emissions. Small wind turbine systems marketed for single residence applications may be the appropriate size for remediation systems, and such wind turbines are readily available at reasonable cost. Another benefit of using domestic wind turbine systems is that they are straightforward to install and operate with minimal training. One of the major drawbacks associated with using wind turbines at remediation sites is that site-specific wind velocity data is typically used …


Membrane Properties Of Intact Rock Cores Of Burlington Limestone, Jefferson Dolomite, Darrington Phyllite, And Low Permeability Concrete, Megan Hart Jan 2009

Membrane Properties Of Intact Rock Cores Of Burlington Limestone, Jefferson Dolomite, Darrington Phyllite, And Low Permeability Concrete, Megan Hart

Doctoral Dissertations

"A number of laboratory studies have shown that clays exhibit membrane properties. However, little research has been performed on lithologies outside of pure clays. Recently, research focusing on mixed sand and clay membrane properties for engineering applications was performed. Still, literature only suggests the possibilities of membrane properties, osmotic or reverse-osmotic, associated with other naturally occurring 'tight' rock types. Therefore, the objectives of this research was to perform a series of hyperfiltration experiments using actual rock discs of Quarry Ridge Jefferson Dolomite, Darrington Phyllite, Lower Burlington Limestone, and low permeability concrete to determine if tight lithologies can function as membranes"--Abstract, …