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The Effect Of Neutron Irradiation On The Properties Of Tl_{0.6}Pb_{0.3}Cd_{0.1}Ba_2ca_2cu_{3}O_{9-Delta} Superconductors, KAREEM ALI JASIM, TARIQ JAFFAR ALWAN, KHALID HADI MAHDI, HAZIM LOUIS MANSOUR 2013 TÜBİTAK

The Effect Of Neutron Irradiation On The Properties Of Tl_{0.6}Pb_{0.3}Cd_{0.1}Ba_2ca_2cu_{3}O_{9-Delta} Superconductors, Kareem Ali Jasim, Tariq Jaffar Alwan, Khalid Hadi Mahdi, Hazim Louis Mansour

Turkish Journal of Physics

The effect of neutron irradiation on phase purity, crystal structure, and electrical resistivity of Tl_{0.6}Pb_{0.3}Cd_{0.1} Ba_2Ca_2Cu_3O_{9-delta} superconductors has been studied before and after irradiation by electrical resistance measurements and X-ray diffraction techniques. The zero-resistance superconducting transition temperature, T_{c(offset)}, of samples systematically decreases by about 5 K with the increase of neutron irradiation fluence up 18.12 \times 10^{10} n cm^{-2}. The crystalline phases showed that the compounds have 2 phases, a high-Tc phase (1223) and low-Tc phase (1212), in addition to the impurity phase. The irradiation led to a decrease in oxygen content and volume fraction of high-Tc phase (1223).


Numerical Experiments For Determining Laser-Induced Temperature Fields, LYUBOMIR KOSTADINOV LAZOV, NIKOLAY ANGELOV PETROV 2013 TÜBİTAK

Numerical Experiments For Determining Laser-Induced Temperature Fields, Lyubomir Kostadinov Lazov, Nikolay Angelov Petrov

Turkish Journal of Physics

Based on the equation of energy balance and the equation of heat conductivity with the help of specialized software, tentative engineering calculations were performed for the process of laser marking by melting and structural changes. The functional capabilities of the software product were examined. Distribution of temperature by layers for samples of tool steel was obtained.


Equilibrium Shapes And Deformations Of Some Rare Earth Nuclei In Cranked Nilsson-Strutinsky Shell Correction Approach, ANTONY JOSEPH, KIZHAKKATH KALAM GIRIJA 2013 TÜBİTAK

Equilibrium Shapes And Deformations Of Some Rare Earth Nuclei In Cranked Nilsson-Strutinsky Shell Correction Approach, Antony Joseph, Kizhakkath Kalam Girija

Turkish Journal of Physics

The nuclear potential energies of neutron-deficient even-even rare earth nuclei ^{150-160}Dy, ^{150-160}Er, ^{150-160}Yb, ^{158,162,166-176}Hf, ^{160,164-178}W, and ^{162,166,170-180}Os are computed within the framework of the cranked Nilsson--Strutinsky shell correction method. The ground state potential energy surface diagrams of these nuclei are analysed in terms of quadrupole deformation and the triaxiality parameter. The nuclear shapes and deformations in the ground state are found to be functions of Z and N. Even though most of the isotopes in this region seem to be prolate in the ground state, oblate and triaxial shapes are also predicted for some isotopes. It is also found that …


Analyses Of Elastically Scattered Charged Pions From Calcium Isotopes And The ^{48}Ca-^{54}Fe Isotone At 180 Mev, ZUHAIR FAYYAD MAHMOUD SHEHADEH 2013 TÜBİTAK

Analyses Of Elastically Scattered Charged Pions From Calcium Isotopes And The ^{48}Ca-^{54}Fe Isotone At 180 Mev, Zuhair Fayyad Mahmoud Shehadeh

Turkish Journal of Physics

The elastic scattering of 180 MeV positively and negatively charged pions, incident on a set of calcium isotopes and the isotone ^{48}Ca - ^{54}Fe, has been analyzed within the framework of a recently updated simple local optical potential. This potential, particularly at the tail region, has been originally determined from available phase shifts using inverse scattering theory and the Klein--Gordon equation as a guide. The analysis is carried out with and without considering the squared potential term in the Klein-Gordon equation. Coulomb effects are accounted for by implementing Stricker's prescription. The numerical results for the angular distributions with isotopic and …


A Fission Model Approach To Alpha Decay And Cluster Radioactivity Of Dy, Er, And Yb Isotopes, KIZHAKKATH KALAM GIRIJA, ANTONY JOSEPH 2013 TÜBİTAK

A Fission Model Approach To Alpha Decay And Cluster Radioactivity Of Dy, Er, And Yb Isotopes, Kizhakkath Kalam Girija, Antony Joseph

Turkish Journal of Physics

Rare earth nuclei are probable candidates for exhibiting cluster radioactivity. In the present work, a theoretical study of alpha decay and heavy cluster emission from Dy, Er, and Yb nuclei in the mass range 150 < A < 190 has been carried out in a fission model approach. Some of the proton-rich isotopes of these nuclei are found to have long half-lives, but within the measurable range. Many of the neutron-rich isotopes under consideration are far from beta stability and the most probable light clusters predicted are highly exotic in nature and the corresponding half-lives are extremely short. However, the decays of most probable heavy clusters predicted have half-lives in the measurable range. The calculations on neutron-rich isotopes indicate the emergence of new magic numbers for protons and neutrons. The centrifugal barrier effect on decay rate of some proton-rich Er isotopes is also investigated.


Kantowski-Sachs Cosmological Model With Wet Dark Fluid In The General Theory Of Relativity, ARUN RAVISHANKAR, BIVUDUTTA MISHRA, PRADYUMN KUMAR SAHOO 2013 TÜBİTAK

Kantowski-Sachs Cosmological Model With Wet Dark Fluid In The General Theory Of Relativity, Arun Ravishankar, Bivudutta Mishra, Pradyumn Kumar Sahoo

Turkish Journal of Physics

The purpose of this study was to investigate the role of wet dark fluid (WDF) in Kantowski-Sachs space-time in the general theory of relativity. In this theory, we solved the field equations for the case where \rho _{WDF}=-2p_{WDF}. Various physical and geometrical properties of the model are also discussed.


A Different Point Of View: A Continuous Tracing Of Acid-Base Titration With Fiber-Optic Sensor, ŞERAFETTİN YALTKAYA, ESRA KENDİR 2013 TÜBİTAK

A Different Point Of View: A Continuous Tracing Of Acid-Base Titration With Fiber-Optic Sensor, Şerafetti̇n Yaltkaya, Esra Kendi̇r

Turkish Journal of Physics

Our main aim was to investigate variations in the refractive index of a solution during chemical reaction. The variation of refractive index was measured through the entire acid--base titration process, especially near the equivalence point. To determine the equivalence point, the conductivity of the solution and the refractive index were measured simultaneously. In this preliminary study, sodium hydroxide and hydrochloric acid were used as the base and the acid solution, respectively. To measure the refractive index variation, a fiber-optic refractive index sensor was designed. The fiber-optic probe was dipped into the solution and acted as a refractive index sensor according …


The Development Of A Novel Technique To Evaluate The Cr-39 Track Response To Alpha Particles, KHALIL IBRAHIM MOHAMMAD, MUZAHIM IBRAHIM AZAWE 2013 TÜBİTAK

The Development Of A Novel Technique To Evaluate The Cr-39 Track Response To Alpha Particles, Khalil Ibrahim Mohammad, Muzahim Ibrahim Azawe

Turkish Journal of Physics

A novel technique is presented for the assessment of the track response of the detector CR-39 to alpha particles by photothermal deflection spectroscopy and image analysis. The 2 new techniques can be implemented to CR-39 as in situ measurements. The proposed techniques offer the possibility of monitoring nuclear radiation directly. Photothermal deflection is described to detect the change in the thermal and optical properties of the track nuclear detector CR-39 when irradiated to alpha particles. In situ image analysis of the photothermal deflection spot is presented to assess the detection of the CR-39 of any nuclear particle or radiation instantaneously.


Development And Utilization Of A Retarding Analyzer For Field Emission Investigation Of Lab_6/W Emitter, AHMED ABDURRAHMAN AHMED AL-TABBAKH, MAHENDRA A. MORE, DILIP S. JOAG 2013 TÜBİTAK

Development And Utilization Of A Retarding Analyzer For Field Emission Investigation Of Lab_6/W Emitter, Ahmed Abdurrahman Ahmed Al-Tabbakh, Mahendra A. More, Dilip S. Joag

Turkish Journal of Physics

A cold field emission from LaB_6/W-coated cathodes has been investigated with a high-accuracy and low-cost retarding field analyzer instrument. Guidelines are provided for measurements of Fowler-Nordheim (FN) characteristics and total energy distributions using a single set-up and direct detection technique to address presumed shortages in sophisticated instrumental requirements for integral investigation. Electron emission from LaB_6 nanoprotrusions, deposited on a tungsten microtip, was successfully investigated. Results emphasize a metallic behavior of the emitter in accordance with the FN theory. No size effects were observed for protrusions of 300 nm in radii.


Best Possible Tilt Angle For Optimal Solar Radiation On An Inclined Surface For Photovoltaic And Solar Thermal Application In Yenagoa, Nigeria, KENNETH PRIYE AINAH, JOHN TARILANYO AFA 2013 TÜBİTAK

Best Possible Tilt Angle For Optimal Solar Radiation On An Inclined Surface For Photovoltaic And Solar Thermal Application In Yenagoa, Nigeria, Kenneth Priye Ainah, John Tarilanyo Afa

Turkish Journal of Physics

Due to the increased use of solar energy resources globally, the study of the available solar resources is essential for systems that use solar energy. This paper uses the Duffie and Beckhman method for estimating the best possible tilt angle for solar radiation using some climatic data such as declination, latitude, and clear index for photovoltaic and solar thermal systems application in the city of Yenagoa. This research was conducted with different tilt angle ranging from 15° to 65° tilt and it was shown that the best tilt angle for solar energy system application for Yenagoa falls in the range …


Planar Waveguide With Left-Handed Material Guiding Film For Refractometry Applications, TAHER M. EL-AGEZ, SOFYAN A. TAYA, MOHAMED M. SHABAT, HANI M. KULLAB 2013 TÜBİTAK

Planar Waveguide With Left-Handed Material Guiding Film For Refractometry Applications, Taher M. El-Agez, Sofyan A. Taya, Mohamed M. Shabat, Hani M. Kullab

Turkish Journal of Physics

A symmetric 3-layer slab waveguide with a left-handed material as a guiding layer is examined analytically for cover refractive index detection. The TM mode dispersion relation of the proposed waveguide is investigated. The sensitivity of the proposed sensor to changes in the cover refractive index and the power flowing within each layer are presented. Some unusual features are found; for example, the sensitivity of the proposed sensor is negative. Moreover, the sensitivity improvement compared with the conventional 3-layer waveguide sensor is approximately a factor of 6.


Exact Traveling Wave Solutions Of The Perturbed Klein--Gordon Equation With Quadratic Nonlinearity In (1+1)-Dimension, Part I: Without Local Inductance And Dissipation Effect, ZAI-YUN ZHANG 2013 TÜBİTAK

Exact Traveling Wave Solutions Of The Perturbed Klein--Gordon Equation With Quadratic Nonlinearity In (1+1)-Dimension, Part I: Without Local Inductance And Dissipation Effect, Zai-Yun Zhang

Turkish Journal of Physics

In this paper, the auxiliary ordinary differential equation is employed to solve the perturbed Klein-Gordon equation with quadratic nonlinearity in the (1+1)-dimension without local inductance and dissipation effect. By using this method, we obtain abundant new types of exact traveling wave solutions.


Bound States And The Oscillator Strengths For The Klein-Gordon Equation Under Möbius Square Potential, HASSAN HASSANABADI, BENTOL HODA YAZARLOO, SABER ZARRINKAMAR 2013 TÜBİTAK

Bound States And The Oscillator Strengths For The Klein-Gordon Equation Under Möbius Square Potential, Hassan Hassanabadi, Bentol Hoda Yazarloo, Saber Zarrinkamar

Turkish Journal of Physics

The Klein-Gordon equation under the equal scalar and vector Möbius square potentials in D-dimensions is solved by using the Nikiforov-Uvarov method. The energy eigenvalues and the corresponding eigenfunctions are obtained and numerically calculated. The oscillator strengths are determined and discussed in terms of parameters of the system.


Defect Studies In Strain-Relaxed Si_{1-X}Ge_X Alloys, ŞEREF KALEM 2013 TÜBİTAK

Defect Studies In Strain-Relaxed Si_{1-X}Ge_X Alloys, Şeref Kalem

Turkish Journal of Physics

Raman light scattering, low-temperature photoluminescence, light-scattering tomography, and hydrogenation were used to investigate optical properties of defects in strain-relaxed Si_{1-x}Ge_x (0.05 \le x \le 0.50) alloys. The photoluminescence emission was characterized by typical zero-phonon, phonon-assisted, and dislocations-related emissions, which are dependent on Ge composition x. However, luminescence spectra exhibited above band-gap features, which are likely associated with the presence of Si-rich regions in the alloys. The results are correlated with light-scattering tomography, revealing the presence of dislocations and Si precipitates. The excess peak at 519 cm^{-1} in Ge-rich samples is supportive of this observation. At low Ge content, a dislocation-related …


Recombination Mechanisms In Hydrogenated Silicon Nanocrystalline Thin Films, ZAKI M. SALEH, SALAM M. KMAIL, SAMAH F. ASSAF, ATIF F. QASRAWI 2013 TÜBİTAK

Recombination Mechanisms In Hydrogenated Silicon Nanocrystalline Thin Films, Zaki M. Saleh, Salam M. Kmail, Samah F. Assaf, Atif F. Qasrawi

Turkish Journal of Physics

The photoconductivity dependences on temperature and illumination intensity were investigated for thin films of hydrogenated nanocrystalline silicon (nc-Si:H) grown by very-high-frequency, plasma-enhanced chemical vapor deposition. The nanocrystalline phase was achieved by heavy hydrogen dilution of silane (SiH_4). We find that the activation energy of the photoconductivity is sensitive to the incident illumination intensity for illumination intensities below 6 mW/cm^2. The photocurrent follows a power-law dependence on illumination intensity (I_{ph}\propto F^{gamma}), with gamma ranging from 0.36 to 0.83. The illumination dependence of the photocurrent suggests 2 different recombination mechanisms depending on temperature. In the lower temperature regime (300-340 K), recombination appears …


Theoretical Modeling And Numerical Solutions Of Some Standard Thermoluminescence Detector Crystals, ERDEM UZUN 2013 TÜBİTAK

Theoretical Modeling And Numerical Solutions Of Some Standard Thermoluminescence Detector Crystals, Erdem Uzun

Turkish Journal of Physics

MCP-100, MYS-N, MTS-7, MTS-100, and MCP-N standard thermoluminescence detector materials are annealed and irradiated. Glow curves and all trap parameters are determined. For these materials new theoretical energy band models are suggested and differential equations governing the charge carrier traffics are derived. The equations are solved by using computer-based numerical methods. During the simulations, experimental data measured in the previous step are given to computer code as the initial conditions. Experimental and numerical results show that the electron-band structures of standard thermoluminescence crystals are represented fairly well by the suggested models.


Chaos And Its Control In Semiconductor Laser With Delayed Negative Optoelectronic Feedback, GUANG-YU JIANG, JUAN ZHANG, YAN HUANG 2013 TÜBİTAK

Chaos And Its Control In Semiconductor Laser With Delayed Negative Optoelectronic Feedback, Guang-Yu Jiang, Juan Zhang, Yan Huang

Turkish Journal of Physics

We reveal theoretically chaos and its control in a semiconductor laser with delayed negative optoelectronic feedback. Under nonperiodic or sinusoidal period optoelectronic current, the semiconductor laser exhibits rich nonlinear dynamics. For a given coupling constant, chaos is shown in a semiconductor laser directly injected by external light. For a photoelectric delayed negative-feedback scheme with sinusoidal period optoelectronic current, the laser can be controlled in single-periodic, dual-periodic, multi-periodic states, and even chaos. The results also illustrate what we think to be a new method to generate various period states in the chaos system.


Effect Of Microwave Sintering On Grain Size And Dielectric Properties Of Barium Titanate, PRAVEENA KURUVA, UMA MAHESHWARA SINGH RAJAPUTRA, SRINATH SANYADANAM, RAMANA MURTHY SARABU 2013 TÜBİTAK

Effect Of Microwave Sintering On Grain Size And Dielectric Properties Of Barium Titanate, Praveena Kuruva, Uma Maheshwara Singh Rajaputra, Srinath Sanyadanam, Ramana Murthy Sarabu

Turkish Journal of Physics

In the present paper, nanosized barium titanate (BaTiO_3) powders were synthesized by microwave hydrothermal method. The structural characterization of as-prepared powders was investigated using X-ray diffraction and Fourier transform infrared spectroscopy. The particle size was estimated using a transmission electron microscope. The nanopowders were sintered at different temperatures using a microwave furnace, followed by characterizations such as X-ray diffraction and field emission scanning electron microscopy. The dielectric constant behavior was observed as a function of frequency (100 Hz to 1 MHz) and temperature. The ferroelectric nature was confirmed from polarization-electric field loops.


Vacuum Properties Of Tarla, HÜSNÜ AKSAKAL, ERTAN ARIKAN, ZAFER NERGİZ 2013 TÜBİTAK

Vacuum Properties Of Tarla, Hüsnü Aksakal, Ertan Arikan, Zafer Nergi̇z

Turkish Journal of Physics

The Turkish Accelerator and Radiation Laboratory at Ankara (TARLA) is a part of the Turkish Accelerator Center project, which was designed to produce an infrared free electron laser in the wavelength band of 2-250 mu m. The beamline of TARLA consists of 4 major sections: injector, beam transport line with linacs, optical cavities, and dump. All system components must be kept under ultrahigh vacuum standards to prevent beam scattering with residual gas. In the present study, the vacuum requirements of the beamline are defined and simulation vacuum and gas flow in the accelerator are presented.


Structure And Odd--Even Staggering Of Mo, Ru, And Pd Even--Even Nuclei In The Framework Of Ibm-1, VIDYA DEVI 2013 TÜBİTAK

Structure And Odd--Even Staggering Of Mo, Ru, And Pd Even--Even Nuclei In The Framework Of Ibm-1, Vidya Devi

Turkish Journal of Physics

In this study, we employed the interacting boson model (IBM-1) to determine the most appropriate Hamiltonian for the study of ^{94-108}Mo, ^{94-110}Ru, and ^{96-114}Pd isotopes in the region A cong 100. The soft rotor formula (SRF) calculation was also done to study these isotopes. Using the best fit values of parameters to construct the Hamiltonian of the IBM-1 we calculated energy levels and B(E2) values for number of transitions in Mo, Ru, and Pd nuclei. The results obtained from the IBM-1 and SRF were compared with experimental data and IBM-2 calculation. On comparing the results it was observed that they …


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