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- Chemical bath (2)
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- C-V measurements (1)
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Articles 1 - 30 of 35
Full-Text Articles in Physical Sciences and Mathematics
The Combined Effect Of Chemical Reaction, Radiation, Mhd On Mixed Convection Heat And Mass Transfer Along A Vertical Moving Surface, Navneet Joshi, Manoj Kumar
The Combined Effect Of Chemical Reaction, Radiation, Mhd On Mixed Convection Heat And Mass Transfer Along A Vertical Moving Surface, Navneet Joshi, Manoj Kumar
Applications and Applied Mathematics: An International Journal (AAM)
This paper discusses the effect of Chemical reaction, Radiation and MHD on laminar mixed convection boundary layer flow and heat and mass transfer on continuously moving vertical surface. The fluid viscosity is assumed to vary as an inverse linear function of temperature and local similarity solutions are obtained for the boundary layer equations subject to isothermally moving vertical surface with uniform speed. The system of non-linear partial differential equations developed in the process is finally transformed into a set of ordinary differential equations with the help of similarity transformations involved in the problem. This set of equations is for different …
Two-Layered Pulsatile Blood Flow In A Stenosed Artery With Body Acceleration And Slip At Wall, Devajyoti Biswas, Uday Shankar Chakraborty
Two-Layered Pulsatile Blood Flow In A Stenosed Artery With Body Acceleration And Slip At Wall, Devajyoti Biswas, Uday Shankar Chakraborty
Applications and Applied Mathematics: An International Journal (AAM)
Pulsatile flow of blood through an artery in presence of a mild stenosis has been investigated in this paper assuming the body fluid blood as a two-fluid model with the suspension of all the erythrocytes in the core region as Bingham Plastic and the peripheral region of plasma as a Newtonian fluid. This model has been used to study the influence of body acceleration, non- Newtonian nature of blood and a velocity slip at wall, in blood flow through stenosed arteries. By employing a perturbation analysis, analytic expressions for the velocity profile, Plug-core radius, flow rate, wall shear stress and …
Bound For The Complex Growth Rate In Thermosolutal Convection Coupled With Cross-Diffusions, Hari Mohan Sharma
Bound For The Complex Growth Rate In Thermosolutal Convection Coupled With Cross-Diffusions, Hari Mohan Sharma
Applications and Applied Mathematics: An International Journal (AAM)
Thermosolutal convection problem of the Veronis’ type coupled with cross–diffusion is considered in the present paper. A semi -circle theorem that prescribes upper limit for the complex growth rate of oscillatory motions of neutral or growing amplitude in such a manner that it naturally culminates in sufficient conditions precluding the non- existence of such motions is derived. Further, results for thermosolutal convection problems with or without the individual consideration of Dufour and Soret effects follow as a consequence.
Solutions Of Nonlinear Second Order Multi-Point Boundary Value Problems By Homotopy Perturbation Method, S. Das, Sunil Kumar, O. P. Singh
Solutions Of Nonlinear Second Order Multi-Point Boundary Value Problems By Homotopy Perturbation Method, S. Das, Sunil Kumar, O. P. Singh
Applications and Applied Mathematics: An International Journal (AAM)
In this paper, we present an algorithm for the numerical solution of the second order multi- point boundary value problem with suitable multi boundary conditions. The algorithm is based on the homotopy perturbation approach and the solutions are calculated in the form of a rapid convergent series. It is observed that the method gives more realistic series solutions that converge very rapidly in physical problems. Illustrative numerical examples are provided to demonstrate the efficiency and simplicity of the proposed method in solving this type of multipoint boundary value problems.
Finite Element Analysis In Porous Media For Incompressible Flow Of Contamination From Nuclear Waste, Abbas Al-Bayati, Saad A. Manaa, Ekhlass S. Ahmed
Finite Element Analysis In Porous Media For Incompressible Flow Of Contamination From Nuclear Waste, Abbas Al-Bayati, Saad A. Manaa, Ekhlass S. Ahmed
Applications and Applied Mathematics: An International Journal (AAM)
A non-linear parabolic system is used to describe incompressible nuclear waste disposal contamination in porous media, in which both molecular diffusion and dispersion are considered. The Galerkin method is applied for the pressure equation. For the brine, radionuclide and heat, a kind of partial upwind finite element scheme is constructed. Examples are included to demonstrate certain aspects of the theory and illustrate the capabilities of the kind of partial upwind finite element approach.
On A Couple-Stress Fluid Heated From Below In Hydromagnetics, Vivek Kumar, Sudhir Kumar
On A Couple-Stress Fluid Heated From Below In Hydromagnetics, Vivek Kumar, Sudhir Kumar
Applications and Applied Mathematics: An International Journal (AAM)
The combined effect of dust particles, magnetic field and rotation on a couple-stress fluid heated from below is considered. For the case of stationary convection, dust particles are found to have a destabilizing effect on the system, whereas the rotation is found to have stabilizing effect on the system. Couple-stress and magnetic field are found to have both stabilizing and destabilizing effects under certain conditions. The oscillatory modes are introduced due to the presence of magnetic field and rotation in the system. The results are presented through graphs in each case.
Particulate Suspension Blood Flow Through A Stenosed Catheterized Artery, V. P. Srivastava, Rochana Vishnoi, Poonam Sinha
Particulate Suspension Blood Flow Through A Stenosed Catheterized Artery, V. P. Srivastava, Rochana Vishnoi, Poonam Sinha
Applications and Applied Mathematics: An International Journal (AAM)
The flow of blood through a narrow catheterized artery with an overlapping stenosis has been investigated. To account for the presence of red cells, blood has been represented by a macroscopic two-phase model (i.e., a suspension of erythrocytes in plasma). The expression for the flow characteristics-the flow rate, the impedance (resistance to flow), the wall shear stress in the stenotic region, the shear stresses at the stenosis two throats and at critical height of the stenosis, has been derived. It is found that the impedance increases with the catheter size, with the hematocrit and also with the stenosis size (height …
Concomitants Of Upper Record Statistics For Bivariate Pseudo–Weibull Distribution, Muhammad Ahsanullah, Saman Shahbaz, Muhammad Qaiser Shahbaz, Muhammad Mohsin
Concomitants Of Upper Record Statistics For Bivariate Pseudo–Weibull Distribution, Muhammad Ahsanullah, Saman Shahbaz, Muhammad Qaiser Shahbaz, Muhammad Mohsin
Applications and Applied Mathematics: An International Journal (AAM)
In this paper the Bivariate Pseudo–Weibull distribution has been defined as a compound distribution of two random variables to model the failure rate of component reliability. The distribution of r–th concomitant and joint distribution of r–th and s–th concomitant of record statistics of the resulting distribution have been derived. Single and product moments alongside the correlation coefficient have also been obtained. Recurrence relation for the single moments has also been obtained for the resulting distributions.
52nd Rocky Mountain Conference On Analytical Chemistry
52nd Rocky Mountain Conference On Analytical Chemistry
Rocky Mountain Conference on Magnetic Resonance
Final program, abstracts, and information about the 52nd annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Snowmass, Colorado, August 1-5, 2010.
Non-Newtonian Arterial Blood Flow Through An Overlapping Stenosis, V. P. Srivastava, Shailesh Mishra
Non-Newtonian Arterial Blood Flow Through An Overlapping Stenosis, V. P. Srivastava, Shailesh Mishra
Applications and Applied Mathematics: An International Journal (AAM)
The effects of an overlapping stenosis on blood flow characteristics in a narrow artery have been investigated. To account for the non-Newtonian behavior, blood has been represented by a Casson fluid. The equation describing the flow has been solved and the expressions for the flow characteristics, namely, the impedance, the wall shear stress, the shear stress at the stenosis throats and the shear stress at the critical height of the stenosis have been derived. It is shown that the impedance increases with the non-Newtonian behavior of blood as well as with the stenosis size. The shear stress at the stenosis …
On The Stability Of Superposed Viscous-Viscoelastic Fluids Through Porous Medium, Pardeep Kumar, Gursharn Jit Singh
On The Stability Of Superposed Viscous-Viscoelastic Fluids Through Porous Medium, Pardeep Kumar, Gursharn Jit Singh
Applications and Applied Mathematics: An International Journal (AAM)
Rayleigh-Taylor instability of a Newtonian viscous fluid overlying Walters’s B viscoelastic fluid through porous medium is considered. For the stable configuration the system is found to be stable or unstable. However, the system is found to be unstable for the unstable configuration. The effects of a uniform horizontal magnetic field and a uniform rotation are also considered. For the stable configuration, in the hydro magnetic case also, the system is found to be stable or unstable. However, for the unstable configuration, the magnetic field and viscoelasticity have got stabilizing effects. The system is found to be unstable for the potentially …
Effects Of Radiation And Variable Viscosity On Mhd Free Convective Flow And Mass Transfer Over A Stretching Sheet With Chemical Reaction, M. A. Seddeek, A. A. Almushigeh
Effects Of Radiation And Variable Viscosity On Mhd Free Convective Flow And Mass Transfer Over A Stretching Sheet With Chemical Reaction, M. A. Seddeek, A. A. Almushigeh
Applications and Applied Mathematics: An International Journal (AAM)
A similarity solution is proposed for the analysis of steady free convection heat and mass transfer over a stretching sheet. The effect of radiation, chemical reaction and variable viscosity on hydromagnetic heat and mass transfer in the presence of magnetic field are investigated. The governing partial differential equations are transformed to the ordinary differential equations using similarity variables, and then solved numerically by means of the fourth-order Runge– Kutta method with shooting technique. A comparison with exact solution is performed and the results are found to be in excellent. Numerical results for the velocity, temperature and concentration as well as …
Section Abstracts: Astronomy, Mathematics, And Physics & Materials Science
Section Abstracts: Astronomy, Mathematics, And Physics & Materials Science
Virginia Journal of Science
Abstracts of papers of the Astronomy, Mathematics, and Physics (Including Materials Science) Section for the 88th Annual Meeting of the Virginia Academy of Science, May 20-21, 2010, James Madison University, Harrisonburg, VA.
Effect Of Substrate Temperature On The Optical Properties Of Thermally Evaporated Zns Thin Films, M. Ruhul Amin Bhuiyan, M. Monjarul Alam, M. Abdul Momin
Effect Of Substrate Temperature On The Optical Properties Of Thermally Evaporated Zns Thin Films, M. Ruhul Amin Bhuiyan, M. Monjarul Alam, M. Abdul Momin
Turkish Journal of Physics
Zinc Sulfide (ZnS) thin films were formed onto cleaned glass substrates using the thermal evaporation method in vacuum. The substrate temperature was varied between as- deposited and 150 °C, keeping the film thickness and the rate of evaporation fixed at 200~nm and 0.3~nm \cdot s^{-1}, respectively. The film thickness was measured in situ by a quartz crystal thickness monitor. The structure of the films was ascertained by x-ray diffraction (XRD) method. The XRD spectra show that the films are polycrystalline in nature, which possess hexagonal structure. The optical properties of the films were ascertained by UV-VIS-NIR spectrophotometer (photon wavelength ranging …
Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films, D. D. O. Eya
Chemical Bath Deposition And Characterization Of Cu_2o-Cu_Xs Thin Films, D. D. O. Eya
Turkish Journal of Physics
Cu_2O-Cu_xS thin films have been deposited on glass substrate by chemical bath deposition technique. The films were obtained by depositing Copper Sulphide (Cu_xS) on Copper (I) Oxide (Cu_2O) and then Cu_2O on Cu_xS. The peak solar transmittance across the thin films were found to be
Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate, Mohammad Imtiazul Haque, Mohammad Umar
Electron Paramagnetic Resonance Study Of Vo^{2+} Doped Single Crystal Of Ferroelectric Guanidinium Uranyl Sulphate Trihydrate, Mohammad Imtiazul Haque, Mohammad Umar
Turkish Journal of Physics
We report result obtained from an EPR study of vanadyl ion (VO^{2+}) in a single crystal of ferroelectric guanidinium uranyl sulphate trihydrate. The Spin-Hamiltonian parameters were also determined via EPR data. VO^{2+} enters the lattice interstitially at two distinguishable sites and resulting vanadyl complexes have nearly axial symmetry.
Influence Of The Nitrogen Concentration On The Electrical Characteristic Of Hydrogenated Amorphous Silicon Nitride (A-Sin_X:H) Based Schottky Diodes, İlker Ay, Hüseyi̇n Tolunay
Influence Of The Nitrogen Concentration On The Electrical Characteristic Of Hydrogenated Amorphous Silicon Nitride (A-Sin_X:H) Based Schottky Diodes, İlker Ay, Hüseyi̇n Tolunay
Turkish Journal of Physics
In this study, the Schottky diode characteristic of hydrogenated amorphous silicon nitride (a-SiN_x:H) samples containing various amounts of nitrogen have been investigated via both I-V and C-V measurements. From forward bias I-V measurements in the dark, the barrier height of samples (\phi_{B0}), ideality factor (\eta ), modified Richardson constant (A^\ast) and series resistances (R_s) have been obtained as the function of temperature for different nitrogen content. In addition, forward and reverse bias current ratios (I_f/I_r) at V~=~1 volt have been investigated as the function of temperature for different nitrogen content. Light sensitivity of the samples has also been investigated under …
Photocurrent And Surface Recombination Mechanisms In The In_Xga_{1-X}N\Slashgan Different-Sized Quantum Dot Solar Cells, Hossein Movla, Foozieh Sohrabi, Jafar Fathi, Hassan Babaei, Arash Nikniazi, Khadije Khalili, Nima Es'haghi Gorji
Photocurrent And Surface Recombination Mechanisms In The In_Xga_{1-X}N\Slashgan Different-Sized Quantum Dot Solar Cells, Hossein Movla, Foozieh Sohrabi, Jafar Fathi, Hassan Babaei, Arash Nikniazi, Khadije Khalili, Nima Es'haghi Gorji
Turkish Journal of Physics
We present a p-i-n structured solar cell with stacked layers of In_xGa_{1-x}N Quantum Dots (QDs) with different indium composition. The photocurrent and surface recombination processes are investigated in the i-region. We have shown that the QDs in the i-region can play the role of both generation or recombination centers. The photocurrent has been calculated by self-consistent method to solve continuity equation of charge carriers in the layers of the i-region. By changing the Indium composition in In_xGa_{1-x}N QDs, the band gap of QDs varies and therefore provides a considerable overlapping with solar spectrum. Proposed SC with different-sized QDs and different …
Vibration Spectra Of Polar Mixing Optical Phonon States And Fröhlich Electron-Phonon Coupling Behaviors In A Wurtzite Zno Quantum Dot, Li Zhang
Turkish Journal of Physics
Based on the dielectric continuum model and Loudon's uniaxial crystal model, the interface-optical-propagating (IO-PR) mixing phonon states of a quasi-zero-dimensional (Q0D) wurtzite cylindrical quantum dot (QD) are investigated. It is found that there are two types of IO-PR mixing phonon modes, i.e. \rho-IO/z-PR mixing modes and the z-IO/\rho-PR mixing modes coexisting in Q0D wurtzite QDs. Numerical calculation on a wurtzite ZnO QD shows that the dispersion frequencies of the mixing modes are discrete functions of the azimuthal quantum number and axial wave-number. The calculated results agree well with the recent experimental spectra in ZnO QDs. An abnormal electron-phonon coupling strength …
Inept Nmr Spectroscopy Of ^{14}Nd_N Groups: Product Operator Theory And Simulation, Deni̇z Türkpençe, İrfan Şaka, Azmi̇ Gençten
Inept Nmr Spectroscopy Of ^{14}Nd_N Groups: Product Operator Theory And Simulation, Deni̇z Türkpençe, İrfan Şaka, Azmi̇ Gençten
Turkish Journal of Physics
Product operator formalism is widely used for the analytical description of multi-dimensional and multiple-pulse NMR experiments for the weakly coupled spin systems having spin-1/2 and spin-1 nuclei. The INEPT NMR experiment is a polarization transfer experiment including J-coupling. In this study, the INEPT NMR experiment was analytically investigated by using product operator theory for weakly coupled IS_n(^{14}ND_n) (I=1, S=1; n=1, 2, 3) spin systems. The obtained theoretical results represent the FID values of ^{14}ND_n groups. In order to make Fourier transform of the obtained FID values, a Maple program is used and then simulated spectra of the INEPT experiment are …
On The S-Wave Jost Solution For Coulomb-Distorted Nuclear Potential, Ujjwal Laha, Bibekananda Kundu
On The S-Wave Jost Solution For Coulomb-Distorted Nuclear Potential, Ujjwal Laha, Bibekananda Kundu
Turkish Journal of Physics
A closed form expression of the off-shell Jost solution for Coulomb plus separable nuclear potential is derived using interacting Green's functions and their integral transforms. As an application of our result the off-shell Jost function for the proton-proton scattering in the ^1S_0 channel is computed for various laboratory energies to investigate the role of long range Coulomb interaction in off-shell scattering.
Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel
Role Of Quadrupole Deformation In Proton Emitting Nuclei In The Medium Mass Region, Chandrasekaran Anu Radha, Velayudham Ramasubramanian, Emmanuel James Jebaseelan Samuel
Turkish Journal of Physics
Nuclear structural studies at and beyond the proton drip line is done with the help of proton radioactivity. It is found that nuclei are not necessarily always spherical. The aim of the present work is to study the role of quadrupole deformation in proton rich nuclei, particularly with respect to odd Z nuclei within the region 50 < Z < 80 near the proton drip line. The deformation is studied using triaxially deformed cranked Nilsson Strutinsky method with tuning. Some of the nuclei in the medium mass region are found to be proton emitters from the ground state with appreciable deformation. Nuclei with 62 < Z < 67 shows considerable deformation that kindled the probability of instability within the nuclei. Significant ground state deformed shapes are observed in the 67 < Z < 73 region.
On Robertson-Walker Universe Model With Variable Cosmological Term And Gravitational Constant In Cosmological Relativity Theory, Kangujam Priyokumar Singh
On Robertson-Walker Universe Model With Variable Cosmological Term And Gravitational Constant In Cosmological Relativity Theory, Kangujam Priyokumar Singh
Turkish Journal of Physics
This paper presents cosmological models in which the gravitational and cosmological constants G and \Lambda are time-dependent. We find a variety of solutions for the variation of cosmological parameters. It is also found that, in the case of matter dominated Robertson-Walker Universe, if the cosmological constant \Lambda \ne 0, the Hubble's constant H is not constant at all but inversely proportional to the cosmic time. The conservation law for the energy momentum tensor is still valid with our law of variation: \Lambda \propto R^{-2} and G\rho \propto \frac{\Lambda }{8\pi}.
Convective Inertia Effects On The Squeeze Film Between Rectangular Parallel Plates, Sikiru Adigun Sanni
Convective Inertia Effects On The Squeeze Film Between Rectangular Parallel Plates, Sikiru Adigun Sanni
Turkish Journal of Physics
This paper investigates the effects of convective inertia on the lubricating characteristics of the squeeze film between parallel rectangular plates. Relaxing a simplifying assumption of the conventional lubrication theory, the paper retains some terms of the convective inertia terms of the Navier-Stokes equations, leading to a derivation of a modified Reynolds equation. The introduction of the convective inertia terms induces two inversely related dimensionless parameters, m and R (the Reynolds number), into the characteristics of the flow behavior. The dimensionless normal (or squeezing) velocity increases monotonically from the lower plate to the upper plate for given value of R. At …
Synthesis And Characterization Of Ruthenium Complexes Containing Chlorophenanthroline And Bipyridine, Anwar A. Bhuiyan, S. Kudo, J. Bartlett
Synthesis And Characterization Of Ruthenium Complexes Containing Chlorophenanthroline And Bipyridine, Anwar A. Bhuiyan, S. Kudo, J. Bartlett
Journal of the Arkansas Academy of Science
The divalent ruthenium polypyridine complexes hold promise as efficient photocatalysts for solar energy conversion schemes. This paper deals with the synthesis and spectroscopic investigation of ruthenium polypyridine complexes, which may be useful as photosensitizers. The homoleptic ruthenium(II) complex Ru(Cl-phen)3(PF6)2 (where Cl-phen = 5- chloro-1,10-phenanthroline), and heteroleptic ruthenium(II) complexes Ru(Cl-phen)2(bpy)(PF6)2, and Ru(Cl-phen)(bpy)2(PF6)2 (where bpy = 2,2′-bipyridine) have been prepared by following the standard synthetic procedure. Silica and alumina column chromatographies were used to purify the compounds. Mass spectroscopy, nuclear magnetic resonance (nmr) spectroscopy, and elemental analysis were used to confirm the identity and the integrity of the complexes. Absorption and emission …
Optical Characterization Of Silver Doped Poly (Vinyl Alcohol) Films, W. A. Jabbar, N. F. Habubi, S. S. Chiad
Optical Characterization Of Silver Doped Poly (Vinyl Alcohol) Films, W. A. Jabbar, N. F. Habubi, S. S. Chiad
Journal of the Arkansas Academy of Science
Silver-doped PVA films were prepared by casting method in order to study the effect of silver on the optical properties of poly(vinyl alcohol) using UV/VIS spectroscopy. It was found that these thin films have an indirect optical band gap (2.4-1.3) eV as the doping percentage increase. Extinction coefficient and refractive index increase as the doping percentage increase, while in general the optical dispersion parameters show an opposite behavior with doping
Analysis Of Gamma Rays And Cosmic Muons With A Single Detector, A. Bachri, P. C. Grant, A. Goldschmidt
Analysis Of Gamma Rays And Cosmic Muons With A Single Detector, A. Bachri, P. C. Grant, A. Goldschmidt
Journal of the Arkansas Academy of Science
In this paper, we report on the construction and upgrade of a 2002 Lawrence Berkeley National Laboratory (LBNL) Quanknet Cosmic Muons Detector. By adapting this model, we modify the electronics and mechanics to achieve a highly efficient gamma-ray and cosmic-ray detector. Each detector module uses a one-inch-thick scintillator, attached to a photomultiplier tube (PMT) and mounted on a solid aluminum frame. A mechanical support was designed to allow flexible positioning between the two modules. The detector uses scintillation to transform passing radiation into detectable photons that are guided toward a photocathode surface of the PMT, triggering the release of photoelectrons …
Phonon Transmission Via Nanojunctions In Bcc Waveguides, Ouahiba Nafa, Boualem Bourahla, Rachid Tigrine
Phonon Transmission Via Nanojunctions In Bcc Waveguides, Ouahiba Nafa, Boualem Bourahla, Rachid Tigrine
Turkish Journal of Physics
Coherent and ballistic phonon transport via nanojunctions between bcc lattices is presented. The model system A/B/A consists of a finite number of bcc atomic layers of an element B sandwiched between two bcc semi-infinite crystals of another element A. The matching method theoretical approach is used to study the dynamical properties of the bcc sandwich system. A calculation is presented for the coherent reflection and transmission scattering probabilities of the system phonons, as elements of a Landauer type scattering matrix. The scattering and transmission spectra via the nanojunctions are analyzed as a function of the incident frequency per propagating mode …
The Investigation Of Hardness And Bonding Behavior In Xb_4, X = {Ce, Th, U, Pa}, Tetraborides By First-Principles, Sezgi̇n Aydin, Aynur Tatar
The Investigation Of Hardness And Bonding Behavior In Xb_4, X = {Ce, Th, U, Pa}, Tetraborides By First-Principles, Sezgi̇n Aydin, Aynur Tatar
Turkish Journal of Physics
The mechanical and electronic properties of XB_4, X = {Ce, Th, U, Pa}, tetraborides have been studied by using first-principles based on density functional theory. The results show that these boron-rich solids are mechanically and thermodynamically stable. From the calculated band structure and density of states, we obtained that they have metallic character. When the calculated parameters related to the crystal structure were considered with the bonding characteristics, the microscopic hardnesses of these boron-rich solids can be theoretically calculated. The obtained hardness values indicate that, these materials are hard, but not superhard. Furthermore, from the detailed hardness analysis, we found …
Computations Of Ultrasonic Parameters Of Lanthanide Metals Ti, Zr And Hf, Pramod Kumar Yadawa, Dharmendra Kumar Pandey, Devraj Singh, Raja Ram Yadav, Giridhar Mishra
Computations Of Ultrasonic Parameters Of Lanthanide Metals Ti, Zr And Hf, Pramod Kumar Yadawa, Dharmendra Kumar Pandey, Devraj Singh, Raja Ram Yadav, Giridhar Mishra
Turkish Journal of Physics
The ultrasonic properties in the hexagonal structured lanthanide metals Ti, Zr and Hf have been studied at room temperature. The higher order elastic constants have been calculated for these metals using Lennard-Jones Potential for evaluating orientation-dependent ultrasonic properties. An anomalous behaviour in orientation dependent velocity is obtained, which is due to the combined effect of second order elastic constants and density. The achieved ultrasonic properties are compared with known physical parameters to differentiate them from third group nitrides/laves phase compounds.