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2007

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Interface And Surface Optical Phonons Spectra In Wurtzite Nitride Quantum Well Wires: Size And Dielectric Effects, Li Zhang Jan 2007

Interface And Surface Optical Phonons Spectra In Wurtzite Nitride Quantum Well Wires: Size And Dielectric Effects, Li Zhang

Turkish Journal of Physics

By employing the method of electrostatic potential expansion, the interface optical (IO) and surface optical (SO) phonon modes and the corresponding Fröhlich-like electron-phonon-interaction Hamiltonian in a Q1D wurtzite cylindrical quantum well wire (QWW) embedded in nonpolar dielectric matrix are derived and studied based on the dielectric continuum model and Loudon's uniaxial crystal model. Numerical calculations for a wurtzite GaN/AlN QWW are mainly focused on the size- and dielectric-dependent IO and SO phonon spectra and electron-IO (SO)phonons coupling functions. Results reveal that, in general, there are two branches of IO phonon modes and one branch of SO mode in the system. …

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A 3-D Hall Sensor For Precise Angular Position Measurements, Konstantin Veselinov Dimitrov Jan 2007

A 3-D Hall Sensor For Precise Angular Position Measurements, Konstantin Veselinov Dimitrov

Turkish Journal of Physics

A 3-D silicon Hall effect sensor for precise angular-position measurement over 360° rotation is presented. This vector microtransducer functionally integrates into a common sensor region two parallel-field Hall devices for in-plane components of the magnetic field and one orthogonal Hall version for the perpendicular for the chip magnetic field. The advantages of this magnetometer are its low channel cross-sensitivities, remarkable simplified device design and high spatial resolution.

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The Extreme Ultraviolet Emission Lines Of Some Cataclysmic Variables At Outburst, Romanus N. C. Eze Jan 2007

The Extreme Ultraviolet Emission Lines Of Some Cataclysmic Variables At Outburst, Romanus N. C. Eze

Turkish Journal of Physics

Using spectral technique, analyses of some astrophysical data from the EUVE satellite in the Extreme Ultraviolet region on accretion disk of some cataclysmic variable were carried out. A number of strong emission lines in 14 CVs were discovered. Most CVs follow a similar trend in the number of ionized elements present in their spectrum while some have very few or no ionized elements in their spectrum. The AM Herculis star, which has the weakest magnetic field of all seven magnetic CVs studied, contain no ionized elements in its EUVE spectroscopy. However, for the rest of the CVs, there is sufficient …

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Evaluations Of Resonance Parameters And Resonance Integral Of Tungsten, A.K.M. Moinul Haque Meaze Jan 2007

Evaluations Of Resonance Parameters And Resonance Integral Of Tungsten, A.K.M. Moinul Haque Meaze

Turkish Journal of Physics

I present evaluated values of resonance parameters and resonance integral for natural tungsten on the basis of experimental transmissions data obtained at the Pohang Neutron Facility (PNF), Republic of Korea. Resonance parameters were obtained by using the Bayesian code SAMMY. The output values of SAMMY were used to evaluate the resonance integral for the capture cross-section.

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Variation Principle For A Linear Potential, J. I. Casaubon, J. P. Cosentino, Adrian H. Buep Jan 2007

Variation Principle For A Linear Potential, J. I. Casaubon, J. P. Cosentino, Adrian H. Buep

Turkish Journal of Physics

We introduce the student to the Quantum Mechanic linear potential (constant force) using new variation wave functions for the ground state and the first excited one. This approach use simple wave functions to describe the exact Airy solution.

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Dynamics Of Stochastic Systems: Effect On Spectral Line Shapes, A. Benotsmane, Ahmed Ahmadouche Jan 2007

Dynamics Of Stochastic Systems: Effect On Spectral Line Shapes, A. Benotsmane, Ahmed Ahmadouche

Turkish Journal of Physics

We present a theoretical approach to describe the dynamics of a system induced by stochastic couplings and undergoing dephasing processes. We consider a model frequently encountered in the study of non-radiative transitions in molecular systems, the case of two configurations stochastically coupled. In this model, we use a system whose excited radiant state is coupled stochastically to a non-radiant state of a lower electronic configuration. We show the line shape for stochastic non-diagonal perturbations to remain Lorentzian. This result is different from the case of frequency modulation where a transition from a Gaussian to a Lorentzian line shape can be …

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Unsteady Mhd Flow Due To Eccentric Rotating Disks For Suction And Blowing, Muhammad R. Mohyuddin Jan 2007

Unsteady Mhd Flow Due To Eccentric Rotating Disks For Suction And Blowing, Muhammad R. Mohyuddin

Turkish Journal of Physics

An exact solution of unsteady flow of a viscous fluid due to a sudden pull with constant velocities of non-coaxial rotations between two porous infinite disks in the presence of uniform transpose magnetic field is investigated. Two different methods are used to obtain the solution at large times and the solution at small times. The effects of magnetic field suction and injection on the velocity distributions are presented.

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Effects Of The Left-Right Asymmetry Parameter In The End Point Of The Tritium-Beta Spectrum, A. Gutierrez-Rodriguez, M. A. Hernandez-Ruiz, F. Ramirez-Sanchez Jan 2007

Effects Of The Left-Right Asymmetry Parameter In The End Point Of The Tritium-Beta Spectrum, A. Gutierrez-Rodriguez, M. A. Hernandez-Ruiz, F. Ramirez-Sanchez

Turkish Journal of Physics

We start with a Left-Right Symmetric Model and we analyze the endpoint of the beta decay of tritium ^3H \rightarrow ^3He + e- + bar{\nu}_e. We applied this model to incorporate the right currents, whereby we propose an amplitude whose leptonic part contains the parameter \lambda defined as a left-right asymmetry parameter which measures the parity violation. We realized a numerical computation for the sensibility of the Mainz and Troitsk experiments for m_{\nu_e}= 2.2 eV; and for the future beta decay experiment KATRIN, which will reach a sensitivity of m_{\nu_e} \approx 0.2 eV. We find that the electron energy spectrum …

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Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Physics

No abstract provided.

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Algebraic Treatment Of Scattering Via The Manning-Rosen Potential Related To The So(2, 1) Group, Nurşen Seçki̇n Görgün, Fi̇kret Işik Jan 2007

Algebraic Treatment Of Scattering Via The Manning-Rosen Potential Related To The So(2, 1) Group, Nurşen Seçki̇n Görgün, Fi̇kret Işik

Turkish Journal of Physics

In this study, we consider SO(2,1) \supset SO(1,1) subgroup reduction from one dimensional scattering systems related to SO(2,1). As an analytical application, we show via algebraic approach the Manning-Rosen potential belongs to the class of potentials corresponding to the reduction SO(2,1) \supset SO(1,1). The wave function and the scattering matrix of the system with this potential were determined.

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Time Dependent Entropy Of Constant Force Motion, Özgür Özcan, Ethem Aktürk, Ramazan Sever Jan 2007

Time Dependent Entropy Of Constant Force Motion, Özgür Özcan, Ethem Aktürk, Ramazan Sever

Turkish Journal of Physics

Time dependent entropy of constant force motion is investigated. Obtained is the joint entropy, also known as the Leipnik entropy. The main purpose of this work is to calculate the Leipnik entropy via a time dependent wave function which is obtained by the Feynman path integral method. For this case it is found the Leipnik entropy increases with time, and is the same behavior as in the free particle case.

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Green Function Of The Morse Potential Using Perturbation Series, B. Boudjedaa, M. T. Meftah, Lyazid Chetouani Jan 2007

Green Function Of The Morse Potential Using Perturbation Series, B. Boudjedaa, M. T. Meftah, Lyazid Chetouani

Turkish Journal of Physics

We find the Green function of the Schrodinger equation for the Morse potential using perturbation series. By Fourier transformation on the end point of the perturbation series, and with some formulas for terms generating the perturbation series, we are able to derive the Green function of the problem.

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Optical Properties And Structural Characterizations Of Sb_2s_3 Thin Films Deposited By Chemical Bath Deposition Technique, F. I. Ezema, A. B. C. Ekwealor, P. U. Asogwa, P. E. Ugwuoke, C. Chigbo, R. U. Osuji Jan 2007

Optical Properties And Structural Characterizations Of Sb_2s_3 Thin Films Deposited By Chemical Bath Deposition Technique, F. I. Ezema, A. B. C. Ekwealor, P. U. Asogwa, P. E. Ugwuoke, C. Chigbo, R. U. Osuji

Turkish Journal of Physics

Thin films of Sb_2S_3 were deposited on glass substrates at 300 K by chemical bath deposition (CBD) technique and annealed at various temperatures. The absorption coefficient \alpha was determined using the absorbance and transmission measurements from a Unico UV-2102 PC spectrophotometer, at normal incidence of light in the wavelength range 200--1000 nm, and the structural characterization were done using XRD and photomicrograph. The films have high absorption, greater than 90%, in the UV region but with moderate transmittance of greater than 50% for as-deposited, and poor transmittance of less than 45% for the annealed throughout the entire spectrum. Plots of …

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A Single Junction Barrier Model For Varistors, Mustapha Tioursi, Abdallah Chaouch Jan 2007

A Single Junction Barrier Model For Varistors, Mustapha Tioursi, Abdallah Chaouch

Turkish Journal of Physics

In this paper, we propose a simplified model that explains the experimental behaviour of the single junction barrier height in varistors. The equation obtained for the barrier height variation versus voltage contains all parameters that characterize the grain boundary and has no adjustable parameters. It allows us to describe the equilibrium state for each voltage level. From this model, it is concluded that the threshold voltage and the nonlinearity coefficient for a single junction barrier are strongly related to the unoccupied traps level at zero bias, when the barrier height at zero bias and the leakage current are related to …

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Application Of Pma Towards Moderating The Charge Storage Capability Of Mis Memory Cell Based On Pecvd Deposited Silicon Nitride Thin Films, Satinder K. Sharma, B. Prasad, Dinesh Kumar Jan 2007

Application Of Pma Towards Moderating The Charge Storage Capability Of Mis Memory Cell Based On Pecvd Deposited Silicon Nitride Thin Films, Satinder K. Sharma, B. Prasad, Dinesh Kumar

Turkish Journal of Physics

A memory capacitor formed from Al/Si_3N_4/Si was prepared by means of trapping and de trapping mechanism of the dielectric films. Charge trapping and interface state characteristics of silicon nitride (Si_3N_4) films deposited by standard plasma enhanced chemical vapor deposition technique were investigated. High frequency capacitance-voltage (C-V), conductance-voltage (G-V) and current voltage (I-V) measurements were carried out at various temperatures on metal-oxide-semiconductor capacitors, for as-deposited samples, post metallization annealed (PMA) at 400 °C and 600 °C samples. The electrically measured characteristics indicate the shift in flat band voltage V_FB in silicon nitride (Si_3N_4) was initially much higher in the as-deposited samples. …

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The Origin Of X-Ray Emission Lines From Ss Cgy, Romanus N. C. Eze Jan 2007

The Origin Of X-Ray Emission Lines From Ss Cgy, Romanus N. C. Eze

Turkish Journal of Physics

SS Cyg is a dwarf nova binary star that undergoes frequent large amplitude outburst within a period of 40 days. SS Cyg was observed with the Chandra x-ray telescope in quiescence on 2000 August 24, and near the peak and early decline of a narrow outburst on 2000 September 12 and 14 (exposures of 47 and 96 ks). The spectrum of the source shows strong emission lines of O VII and O VIII in all three observations. These lines, we note, originate from the boundary layer.

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Study Of Vickers´ Micro Hardness On Inbi_0.85sb_0.15 Single Crystals, Dimple Shah, G. R. Pandya, S. M. Vyas, M. P. Jani Jan 2007

Study Of Vickers´ Micro Hardness On Inbi_0.85sb_0.15 Single Crystals, Dimple Shah, G. R. Pandya, S. M. Vyas, M. P. Jani

Turkish Journal of Physics

InBi_0.85Sb_0.15 single crystals have been grown by zone-melting method. The growth velocity was 0.8 cm/h and the freezing interface temperature was 35 °C/cm. A Vickers' projection microscope was used for the study of micro hardness of the crystals. Hardness tests were carried out on the as-cleaved, cold-worked and annealed surfaces of the crystals. The effect of perfection of crystals on micro hardness with respect to the cold-worked, as-cleaved and annealed crystals have been studied and the results are reported.

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Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Physics

No abstract provided.

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Longitudinal Form Factor Of Isoscalar Particle-Hole States In ^{16}O, ^{12}C And ^{40}Ca With M3y Interaction, Ali H. Taqi, Raad A. Radhi Jan 2007

Longitudinal Form Factor Of Isoscalar Particle-Hole States In ^{16}O, ^{12}C And ^{40}Ca With M3y Interaction, Ali H. Taqi, Raad A. Radhi

Turkish Journal of Physics

Longitudinal form factors of the low-lying, T = 0, particle-hole states of ^{16}O, ^{12}C and ^{40}Ca are studied in the framework of Random Phase Approximation RPA. The basis of single particle states is considered to include 0s, 0p, 1s-0d and 0f-1p. The Hamiltonion is diagonalized in the presence of Michigan three-rang Yakawa (M3Y) interaction and compared with our previous results depend on Modified Surface Delta Interaction MSDI interaction. Admixture of higher configuration up to 2p-1f is considered for the ground state. Effective charges are used to account for the core polarization effect. Comparisons are made to experimental data where available …

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Magnetic Levitation Of A Small Magnetic Ring Above Cylindrical Superconductor Sample In The Meissner State, H. M. Al-Khateeb, F. Y. Alzoubi, M. K. Alqadi, N. Y. Ayoub Jan 2007

Magnetic Levitation Of A Small Magnetic Ring Above Cylindrical Superconductor Sample In The Meissner State, H. M. Al-Khateeb, F. Y. Alzoubi, M. K. Alqadi, N. Y. Ayoub

Turkish Journal of Physics

The levitation force between a cylindrical superconductor in the Meissner state and a small magnetic ring was calculated using the dipole-dipole interaction model under the assumption that the magnetic ring is small compared with the physical dimensions of the system. We obtained analytical expressions for the levitation forces as a function of the geometrical parameters of the ring and the superconductor sample as well as the height of magnetic ring. We analyzed the levitation force in two configurations of the magnetic moment of the small ring with respect to the surface of the superconductor: one horizontal in which the magnetic …

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Thickness Dependent Structural, Electrical And Optical Properties Of Chemically Deposited Nanopartical Pbs Thin Films, A. U. Ubale, A. R. Junghare, N. A. Wadibhasme, A. S. Daryapurkar, R. B. Mankar, V. S. Sangawar Jan 2007

Thickness Dependent Structural, Electrical And Optical Properties Of Chemically Deposited Nanopartical Pbs Thin Films, A. U. Ubale, A. R. Junghare, N. A. Wadibhasme, A. S. Daryapurkar, R. B. Mankar, V. S. Sangawar

Turkish Journal of Physics

Nanostructured thin films have attracted the attention of an increasing number of researchers from several disciplines during the last ten years, due to their outstanding electronic and optical properties and extensively useful applications in various optoelectronic devices. PbS thin films were deposited onto glass substrate by the method of chemical bath deposition (CBD) at 330 K temperature. The structure and surface morphology of the films were characterized by X-ray diffraction and scanning electron microscopy. The optical investigation showed that, depending on thickness films have direct allowed transitions in the range 1.88-2.28 eV. The decrease in dc dark resistivity with increase …

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Preparation And Study Of The Structural, Optical And Electrical Properties Of Cu(In,Ga)Se_2 Thin Films, Athar Javed Jan 2007

Preparation And Study Of The Structural, Optical And Electrical Properties Of Cu(In,Ga)Se_2 Thin Films, Athar Javed

Turkish Journal of Physics

Thin film samples of Cu(In,Ga)Se_2 (CIGS) were prepared at room temperature by physical vapor deposition (PVD) technique using resistive heating method onto soda lime glass substrates. Deposition conditions were same for all the samples. The prepared samples were annealed in vacuum at temperature of 200 °C for 5, 10, 15, 30 and 60 minutes and were characterized structurally, optically and electrically. The structural analysis indicate the partial formation of quaternary CIGS compounds for the samples which were annealed in vacuum at 200 °C for 30 and 60 minutes. XRD analysis indicate that there is a continuous growth and improvement in …

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Cover And Contents Jan 2007

Cover And Contents

Turkish Journal of Physics

No abstract provided.

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Silver Mode For Heavy Higgs Search In The Presence Of A Fourth Sm Family, Saleh Sultansoy, Gökhan Ünel Jan 2007

Silver Mode For Heavy Higgs Search In The Presence Of A Fourth Sm Family, Saleh Sultansoy, Gökhan Ünel

Turkish Journal of Physics

We investigate the possible enhancement to the discovery of the heavy Higgs boson through the possible fourth standard model family heavy neutrino. Using the channel h\to\nu_4\bar{\nu}_4 \to \mu W\mu W \to \mu j j\mu j j it is found that for certain ranges of the Higgs boson and \nu_4 masses, LHC could discover both of them simultaneously with 1fb^{-1} integrated luminosity.

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Five Dimensional Anisotropic Homogeneous Cosmological Models In Second Self Creation Theory Of Gravitation, Ganeshwar Mohanty, Kamal Lochan Mahanta Jan 2007

Five Dimensional Anisotropic Homogeneous Cosmological Models In Second Self Creation Theory Of Gravitation, Ganeshwar Mohanty, Kamal Lochan Mahanta

Turkish Journal of Physics

Five dimensional homogeneous anisotropic cosmological models in Barber's second self creation theory are constructed when the gravitational field is generated by a perfect fluid. Under the power law dependence of the scale factors, the perfect fluid models degenerate Zeldovich fluid models. The physical and geometrical features of these models are discussed.

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On The Eigensolutions Of The One-Dimensional Kemmer Oscillator, A. Boumali Jan 2007

On The Eigensolutions Of The One-Dimensional Kemmer Oscillator, A. Boumali

Turkish Journal of Physics

In the present paper, we solve the one-dimensional Kemmer equation in the presence of the Dirac oscillator potential. Following Greiner in [23], we have shown that the eigensolutions are decoupled in two sets.

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An Investigation Of The Effects Of Hydrogen On Local Strain Fields And Structural Disorder-To-Order Transition In Hydrogenated Amorphous Silicon, Aniekan Magnus Ukpong Jan 2007

An Investigation Of The Effects Of Hydrogen On Local Strain Fields And Structural Disorder-To-Order Transition In Hydrogenated Amorphous Silicon, Aniekan Magnus Ukpong

Turkish Journal of Physics

This study utilizes the fluctuations in the mean silicon-silicon near neighbour distances and local atomic-level stresses to study the chemically-induced disorder-to-order transition in hydrogenated amorphous silicon as a function of hydrogen concentration C_H. The correlation between a suitable stress and structure parameter shows a three-stage structure transition that culminates in the formation of a crystalline phase at high C_H. In the low C_H limit, the structural changes are characterized by a linear response to stress giving a rigidity modulus of 73.43+-15 GPa. In the intermediate and high C_H limits, the stress-structure correlation shows a volume-dependence. At very high hydrogen concentrations, …

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Optical Properties And Determination Of Thermal Transformation Parameters For Se_{0.65}Te_{0.35} High Reflectance Thin Films, Ayman Ahmed El-Amin, Aly Mohammed Badr, Foaud Abdel-Wahaab Jan 2007

Optical Properties And Determination Of Thermal Transformation Parameters For Se_{0.65}Te_{0.35} High Reflectance Thin Films, Ayman Ahmed El-Amin, Aly Mohammed Badr, Foaud Abdel-Wahaab

Turkish Journal of Physics

Chalcogenide glasses Se-Te have been prepared from the high purity constituent elements. Thin films of these materials have been deposited by vacuum evaporation. The thickness effects on the optical properties have been performed for the as-deposited films. The impact of varying thickness on the value of the optical gap is also reported and discussed. The resultant films were in amorphous nature. The reflectance and transmittance spectra were measured for the mentioned films and analyzed in the incident photon energy range from 1.16 to 2.47 eV. The refractive indices were determined as a function of wavelength via the transmittance analysis in …

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Electrical Resistivity Of Liquid Alkali Na-Based Binary Alloys, Aditya M. Vora Jan 2007

Electrical Resistivity Of Liquid Alkali Na-Based Binary Alloys, Aditya M. Vora

Turkish Journal of Physics

The study of the electrical resistivity \rho_L of alkali Na-based binary alloys Na_{1-x}Li_x, Na_{1-x}K_x, Na_{1-x}Rb_x and Na_{1-x}Cs_x have been made by well-recognized model potential of Gajjar et al. The most recent exchange and correlation functions due to Farid et al (F) and Sarkar et al (S) are used for the first time in the study of electrical resistivity of liquid binary mixtures and found suitable for such study. The results, due to the inclusion of Sarkar et al's local field correction function, are found superior to those obtained due to Farid et al's local field correction function. Electrical resistivity of …

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"Appalachian Ingenuity" In Action: Activists Reach Beyond Traditional Economic Development In Kentucky, Stephanie Ann Blessing Jan 2007

"Appalachian Ingenuity" In Action: Activists Reach Beyond Traditional Economic Development In Kentucky, Stephanie Ann Blessing

University of Kentucky Master's Theses

This Thesis is an exploration into social change strategies in Appalachia that are alternative to conventional economic development practices and discourses. Drawing from original interviews with social justice activists in central and eastern Kentucky, I document a diversity of subversive discourses circulating in Appalachia, and I delineate models alternative to development that are driving action in several different communities. Through what one of my interviewees described as Appalachian ingenuity,1 individuals are enacting extremely hopeful and imaginative projects, and they are conjuring unique formulations that contribute to academic theories on alternative economies, capitalocentrism, neoliberalism, postmodern economics, anti-development, post-development, and spatial strategies …

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