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Articles 451 - 480 of 1382
Full-Text Articles in Physical Sciences and Mathematics
Zno-Based Nanostructures For Diluted Magnetic Semiconductor, Millaty Mustaqima, Chunli Liu
Zno-Based Nanostructures For Diluted Magnetic Semiconductor, Millaty Mustaqima, Chunli Liu
Turkish Journal of Physics
Since the prediction by Dietl et al. in the year 2000, extensive research activities have been focused on the ZnO-based diluted magnetic materials (DMSs). Earlier works were mainly performed using bulk or thin film materials with transition-metal doping, and diverse magnetic properties including ferromagnetism, paramagnetism, and diamagnetism have been reported. Identifying the dominant mechanism of the ferromagnetic ordering and realizing reproducible ferromagnetism above room temperature have been the main research issues, but a consensus is still lacking even today. Recently, reports on ZnO nanostructures with ferromagnetic behavior have been growing due to the novel properties brought about by the high …
The Influence Of Tio_2 Nanostructure Properties On The Performance Of Tio_2-Based Anodes In Lithium Ion Battery Applications, Xiang Liu, Qian Sun, Fangzhou Liu, Aleksandra B. Djurisic, Alan Man Ching Ng, Maohai Xie, Tom Wood, Juan Antonio Zapien, Changzhong Liao, Kaiming Shih
The Influence Of Tio_2 Nanostructure Properties On The Performance Of Tio_2-Based Anodes In Lithium Ion Battery Applications, Xiang Liu, Qian Sun, Fangzhou Liu, Aleksandra B. Djurisic, Alan Man Ching Ng, Maohai Xie, Tom Wood, Juan Antonio Zapien, Changzhong Liao, Kaiming Shih
Turkish Journal of Physics
We investigated the properties of 7 different titanium dioxide nanostructures with different crystal structures (3 anatase, 2 rutile, and 2 mixed anatase--rutile phase). Nanoparticle samples and mesoporous sphere samples were investigated. Even for the same crystal structure, significant variations in performance were observed for anatase titania samples, while 2 rutile samples exhibited similar performance inferior to anatase-based anodes. Mixed-phase samples also exhibited lower specific capacity compared to the best performing anatase samples, and in this case a significant difference in performance was observed between nanoparticles and mesoporous spheres.
Processing Of Germanium For Integrated Circuits, Ray Duffy, Maryam Shayesteh, Ran Yu
Processing Of Germanium For Integrated Circuits, Ray Duffy, Maryam Shayesteh, Ran Yu
Turkish Journal of Physics
In this review paper the authors will focus on Ge processing for integrated circuits. The key areas that require the most attention are substrates and integration, gate dielectrics, and access resistance. We will discuss each of these topics in turn, while also reviewing the most scaled Ge field-effect-transistor devices, and consider how modelling activities have matured for Ge in recent years.
Fabrication And Characterization Of Green Light Emitting Diode, Shirin Siahjani, Matthew White, Niyazi Serdar Sariciftci, Şule Erten Ela
Fabrication And Characterization Of Green Light Emitting Diode, Shirin Siahjani, Matthew White, Niyazi Serdar Sariciftci, Şule Erten Ela
Turkish Journal of Physics
Phosphorescent polymer light emitting diodes (PLEDs) have been fabricated and characterized. A PLED was configured in an ITO/PEDOT:PSS/TPD:PBD:PVK:Ir(mppy)_3/LiF/Al device structure. Thicknesses of the active layer were optimized for an efficient phosphorescent organic light-emitting diode (OLED) device. The uniform mixing of the active layer was varied with different thicknesses. A hole transport layer of PEDOT:PSS was deposited in a thickness of 35 nm and an emissive layer of TPD:PBD:PVK:Ir(mppy)_3 was deposited in thicknesses of 90 nm, 56 nm, 40 nm, and 35 nm. The 56 nm thickness of the active layer was determined as the proper thickness according to results of …
Device Architectures In Organic Photovoltaics, James T. Mcleskey Jr
Device Architectures In Organic Photovoltaics, James T. Mcleskey Jr
Turkish Journal of Physics
The various device structures used in organic polymer solar cells are reviewed. The operating principles behind these devices are explained in order to provide the reasoning behind the different structures. The incorporation of nanostructures into both bilayer and bulk heterojunction devices to improve exciton separation, charge transport, and light absorption is discussed. Novel ideas such as electrospun fibers and supramolecules are also covered. Finally, the impact of these structures on overall efficiency is evaluated.
Amorphous And Micromorph Si Solar Cells: Current Status And Outlook, Vitaliy Avrutin, Natalia Izyumskaya, Hadis Morkoç
Amorphous And Micromorph Si Solar Cells: Current Status And Outlook, Vitaliy Avrutin, Natalia Izyumskaya, Hadis Morkoç
Turkish Journal of Physics
An overview of the current status and prospects of thin-film Si photovoltaics, including both hydrogenated amorphous and microcrystalline Si as well their combination known as micromorph solar cells, with a major focus on the technological development is given. Although thin-film Si solar cells have been one of the first commercially successful photovoltaic devices, today they face a tremendous challenge from variety of bulk Si technologies (mono- and multicrystalline Si) and compound-semiconductor thin-film solar cells, both of which have managed to substantially reduce the production cost and improve power conversion efficiency. Thin-film Si photovoltaics benefiting from the mighty mainstream Si industry …
Electron Field Emission From Nanostructured Semiconductors Under Photo Illumination, Oktay Yilmazoglu, Anatoli Evtukh, Shihab Al-Daffaie, Jens-Peter Biethan, Dimitris Pavlidis, Vladimir Litovchenko, Hans L. Hartnagel
Electron Field Emission From Nanostructured Semiconductors Under Photo Illumination, Oktay Yilmazoglu, Anatoli Evtukh, Shihab Al-Daffaie, Jens-Peter Biethan, Dimitris Pavlidis, Vladimir Litovchenko, Hans L. Hartnagel
Turkish Journal of Physics
New device concepts and materials for the fabrication of compact high-frequency vacuum sources and micro-nano-integrated X-ray sources are of particular interest for broadband communication, security screening of packages and chemical materials, biomedical examination, and other applications. This article integrates results on GaN- and ZnO-based nano and self-assembled structures. They were used as field emitter tips for cold electron emission at high local electric fields as well as for photoassisted field emitters to generate bunched electrons directly from the emitter tip. The results on functional field emitters as cold electron sources will be presented. They are key elements for building, among …
Nanosphere Lithography - Exploiting Self-Assembly On The Nanoscale For Sophisticated Nanostructure Fabrication, Eser Metin Akinoglu, Anthony John Morfa, Michael Giersig
Nanosphere Lithography - Exploiting Self-Assembly On The Nanoscale For Sophisticated Nanostructure Fabrication, Eser Metin Akinoglu, Anthony John Morfa, Michael Giersig
Turkish Journal of Physics
We demonstrate the fabrication of sophisticated nanostructures using nanosphere lithography (NSL). These include periodic triangular and pyramidal islands as well as periodically perforated thin films and cavities on the nano- and microscale. Furthermore, periodic arrays of vertically standing multiwalled carbon nanotubes are grown by plasma enhanced chemical vapor deposition from catalyst islands that were prepatterned by NSL. Moreover, we discuss the applicability of NSL to rough surfaces and show that the ratio between nanosphere size and roughness is determinant of the resulting nanostructure produced. Excellent, limited, and bad applicability of NSL are shown for smooth, rough, and very rough surfaces, …
A Fission Model Approach To Alpha Decay And Cluster Radioactivity Of Dy, Er, And Yb Isotopes, Kizhakkath Kalam Girija, Antony Joseph
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.
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
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).
Chaos And Its Control In Semiconductor Laser With Delayed Negative Optoelectronic Feedback, Guang-Yu Jiang, Juan Zhang, Yan Huang
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.
Synthesis And Optical Characterization Of Zn_{1-X}Mg_Xs: Eu Nanoparticles, Alexander Nwabueze Amah, Audu Onoja, Richard Akpagher
Synthesis And Optical Characterization Of Zn_{1-X}Mg_Xs: Eu Nanoparticles, Alexander Nwabueze Amah, Audu Onoja, Richard Akpagher
Turkish Journal of Physics
Zn_{1-x}Mg_xS: Eu^{3+} nanoparticles were synthesized by a facile co-precipitation technique with varying magnesium concentrations (0 =< x =< 0.20). X-ray diffraction results showed a mixture of cubic and hexagonal structures. There was an observed peak shift towards higher angles, decrease in peak intensities, disappearance of other peaks, and increase in diffraction peak broadening as Mg concentration increased. The estimated average particle sizes ranged from 2.0 nm to 8.79 nm. Scanning electron microscopy results showed smooth and uniform surface morphology. Energy dispersive X-ray studies indicated that the samples contained mainly Zn, S, and Eu because of the low detection limit for Mg. UV-Vis absorption spectrophotometer results showed a blue shift in energy due to quantum confinement as Mg concentration increased.
Structure And Odd--Even Staggering Of Mo, Ru, And Pd Even--Even Nuclei In The Framework Of Ibm-1, Vidya Devi
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 …
Regular And Chaotic Motions In Hénon-Heiles Like Hamiltonian, Idugba Mathias Echi, Alexander Nwabeze Amah, Emmanuel Anthony
Regular And Chaotic Motions In Hénon-Heiles Like Hamiltonian, Idugba Mathias Echi, Alexander Nwabeze Amah, Emmanuel Anthony
Turkish Journal of Physics
The dynamics of a system subjected to a potential equal to the sum of the Hénon--Heiles potential and that of hydrogen in an electric field was studied. The 4 Hamilton's equations of motion follow from the Hamiltonian and they were integrated numerically using the Runge-Kutta fourth order method. The Poincaré surface of a section fixed at x = 0 and px> 0 was used to reduce the phase space to a 2-dimensional plane. The analysis of the Poincaré surface, the Lyapunov exponent, and the autocorrelation shows that as the constant of motion, E, increases from 0.30 to 0.45, the dynamics …
Spin-One Dkp Equation In The Presence Of Nonminimal Vector Woods-Saxon Potential In (1 + 1) Dimensions, Hassan Hassanabadi, Zahra Molaee, Saber Zarrinkamar
Spin-One Dkp Equation In The Presence Of Nonminimal Vector Woods-Saxon Potential In (1 + 1) Dimensions, Hassan Hassanabadi, Zahra Molaee, Saber Zarrinkamar
Turkish Journal of Physics
The Duffin-Kemmer-Petiau equation in the presence of a nonminimal vector Woods-Saxon potential is solved for spin-one particles via the Nikiforov-Uvarov method. The reflection and transmission coefficients of the general form of the DKP equation in the presence of a nonminimal vector interaction are discussed.
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.
Temperature Dependence For The Synthetic Magnetization Of A Rotating Bose Gas In Harmonic Trap, Azza M. Elbadry
Temperature Dependence For The Synthetic Magnetization Of A Rotating Bose Gas In Harmonic Trap, Azza M. Elbadry
Turkish Journal of Physics
In this paper, the temperature dependence for synthetic magnetization \bar M of a rotating Bose gas in harmonic trap and the magnetic field dependence of the critical temperature are investigated. A simple semiclassical approximation for the density of state approach is used in this study. The suggested approach simultaneously gives corrections to quantities which arise from the finite size and interatomic interaction effects. The calculated results show that the critical temperature decreases due to the increase of the synthetic magnetic field. The synthetic magnetization also exhibits a characteristic temperature dependence. It is proportional to T^3 if \bar T < \bar T_c, while it is proportional to T if \bar T > \bar T_c. …
Numerical Experiments For Determining Laser-Induced Temperature Fields, Lyubomir Kostadinov Lazov, Nikolay Angelov Petrov
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.
Analysis Of Amplitude And Slope Diffraction Coefficients, Mehmet Bariş Tabakcioğlu, Ahmet Cansiz
Analysis Of Amplitude And Slope Diffraction Coefficients, Mehmet Bariş Tabakcioğlu, Ahmet Cansiz
Turkish Journal of Physics
The diffraction mechanism is used for field prediction in both light and shadowed regions. Slope and amplitude diffraction coefficients are vital to predict the field strength at the receiver accurately. In this paper, amplitude and slope diffraction coefficients for one of the ray theoretical models, the slope uniform theory of diffraction with convex hull (S-UTD-CH) model, are analyzed. Moreover, diffraction coefficients are given for knife-edge and wedge structures.
Equilibrium Shapes And Deformations Of Some Rare Earth Nuclei In Cranked Nilsson-Strutinsky Shell Correction Approach, Antony Joseph, Kizhakkath Kalam Girija
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 …
Effect Of Stepwise Replacement Of Lif By Zno On Structural And Optical Properties Of Lif.B_2o_3 Glasses, Susheel Arora, Virender Kundu, Dev Raj Goyal, Anup Singh Maan
Effect Of Stepwise Replacement Of Lif By Zno On Structural And Optical Properties Of Lif.B_2o_3 Glasses, Susheel Arora, Virender Kundu, Dev Raj Goyal, Anup Singh Maan
Turkish Journal of Physics
Zinc fluoroborate glasses with compositions xZnO.(40 - x) LiF.60B_2O_3 (x = 0, 5, 10, 15, and 20) were synthesized by the melt-quench method. The amorphous nature of the glassy samples was confirmed by XRD analysis. The nature of the bonds formed and the role of various species in the composition of the glasses were examined using FTIR spectroscopy. FTIR analysis showed shifting of an absorption band with the addition of ZnO. A UV-visible study was carried out to calculate the optical band gap energy, E_gIt was found that E_gdecreased with increase in concentration of ZnO up to x = 15 …
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
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 …
A Different Point Of View: A Continuous Tracing Of Acid-Base Titration With Fiber-Optic Sensor, Şerafetti̇n Yaltkaya, Esra Kendi̇r
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 …
Bound States And The Oscillator Strengths For The Klein-Gordon Equation Under Möbius Square Potential, Hassan Hassanabadi, Bentol Hoda Yazarloo, Saber Zarrinkamar
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.
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
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.
Planar Waveguide With Left-Handed Material Guiding Film For Refractometry Applications, Taher M. El-Agez, Sofyan A. Taya, Mohamed M. Shabat, Hani M. Kullab
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.
Recombination Mechanisms In Hydrogenated Silicon Nanocrystalline Thin Films, Zaki M. Saleh, Salam M. Kmail, Samah F. Assaf, Atif F. Qasrawi
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 …
Effect Of Microwave Sintering On Grain Size And Dielectric Properties Of Barium Titanate, Praveena Kuruva, Uma Maheshwara Singh Rajaputra, Srinath Sanyadanam, Ramana Murthy Sarabu
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
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.
Level Structure Of ^{210}Po By Means Of Surface Delta Interaction, Ali Khalaf Hasan, Abdul Ridha Hussain Subber
Level Structure Of ^{210}Po By Means Of Surface Delta Interaction, Ali Khalaf Hasan, Abdul Ridha Hussain Subber
Turkish Journal of Physics
Within the framework of the shell model, we consider the residual interaction to be a surface delta interaction. This interaction has been applied in the calculation of the energy levels of ^{210}Po, which belong to N = 126 magic closed shell nuclei. The pure and the configuration mixings are applied in the calculations of matrix elements. The predicted energy levels are compared with experimental data.