This document reports on a first principles study of the electronic, elastic, and thermal properties of RECd (RE = La, Ce, and Pr) intermetallic compounds using density functional theory. The compounds were found to be metallic in nature. Elastic constants were calculated and satisfied mechanical stability criteria, though values have not been experimentally measured. Among the compounds, PrCd was predicted to be most ductile based on its bulk to shear modulus ratio. Thermal properties like Debye temperature were also derived from the calculated elastic constants. This study provides the first theoretical predictions of elastic properties of these RECd intermetallic compounds.
First principles study on structural and electronic properties of re ag (re= ...Alexander Decker
This article presents a first principles study of the structural, electronic, and mechanical properties of REAg (RE = Y, La, Pr, Er) intermetallic compounds using density functional theory. The results show that these compounds crystallize in the B2 (CsCl-type) structure and are metallic. Lattice constants, bulk moduli, and densities of states are calculated and compared to experimental values where available, showing good agreement. Electronic band structures indicate hybridization between RE d/f states and Ag s/p states near the Fermi level. Partial densities of states of the d orbitals suggest ErAg and YAg are more ductile than LaAg and PrAg due to delocalized Ag d states. Overall
First principles study on structural, electronic, elastic and thermal propert...Alexander Decker
The document discusses a first principles study of the structural, electronic, elastic, and thermal properties of equiatomic MTi compounds (M=Fe, Co, Ni) using density functional theory calculations. The calculations determine the ground state properties, electronic band structures, density of states, and elastic constants of FeTi, CoTi, and NiTi. The results for lattice constants, bulk moduli, and densities of states at the Fermi level are in good agreement with available experimental and theoretical values. NiTi is found to be the most ductile of the three compounds based on calculations of its B/G ratio and Cauchy pressure. The thermal properties, including the Debye temperatures, are also calculated for the first time.
IRJET- Investigation of Structural, Elastic, Electronic and Optical Prope...IRJET Journal
- The document investigates the structural, elastic, electronic, and optical properties of the ternary compound KLiTe using density functional theory calculations.
- The calculated lattice parameters are in good agreement with experimental values. Elastic constants indicate KLiTe is mechanically stable with brittle behavior.
- Electronic structure calculations show KLiTe is a semiconductor with a direct bandgap of 2.37 eV. Optical properties, such as high reflectivity in the UV region, suggest potential use as a coating material.
Study on rare-earth–doped type-I germanium clathratesYang Li
The synthesis of rare-earth clathrates RExBa8xGa16Ge30 is a challenging task. The Group IV clathrates with rare-earth doping are hardly to be experimentally prepared, except Eu clathrate. In the current study, the first-principle method based on the density functional theory was implemented. The effects of the various RE elements doping on the binding energy and chemical reaction drive energy were studied by optimizing the phase structure. The energy calculations suggest that it is difficult to synthesize RE clathrates without Ga doping. The function of Ga doping is to effectively increase the drive chemical reaction in order to synthesize the clathrates. The simulation shows that, besides Eu, other rare-earth elements, such as Sm, Nd, and Yb can also enter cage lattice in the considering of drive energy, thus making it possible to synthesize the (RE,Ba)8Ge30Ga16 clathrates.
The document summarizes research on simulating the surface tension of liquid nickel through molecular dynamics and density functional theory calculations. It describes using embedded atom method interatomic potentials to model nickel, compares calculated density-temperature data to experimental values, and presents a molecular dynamics simulation of a molten nickel nanoparticle in good agreement with experiment. Future work is outlined on modeling nickel-aluminum alloys, oxidation effects, and temperature-dependent interdiffusion at metal-metal interfaces.
Heat Capacity of BN and GaN binary semiconductor under high Pressure-Temperat...IOSR Journals
In this paper, we have calculated the molar heat capacity for cubic zinc blende (cZB) BN and GaN binary semiconductors at high pressure-temperature (PT). For the calculation of heat capacity, we firstly obtained the Debye temperature (ϴD) variation with temperature and at higher temperature it becomes constant with temperature in quasi-harmonic approximation limits. We have also calculated the static Debye temperature (ϴD) from elastic constant for the both BN and GaN binary semiconductors. The elastic constants are calculated from the energy-strain relation using plane wave method in DFT approach. All the calculated results are well consistence with experimental and reported data
Effect of sodium doping on thermal properties of perovskite r mn o3 for poten...Alexander Decker
This document discusses the effect of sodium doping on the thermal properties of perovskite rare earth manganites RMnO3 for potential magnetoelectric applications. It studies the thermal, elastic, and cohesive properties of sodium-doped rare earth manganites R1-xNaxMnO3 (R3+ = La, Pr, Tb) using a modified rigid ion model and atom in molecules theory. It finds that sodium doping increases the A-site cation radius, affecting properties like lattice specific heat, Debye temperature, thermal expansion, bulk modulus, and cohesive energy. These thermal properties are important for determining the compatibility of components in thermoelectric devices and revealing electron-lattice coupling in
The document discusses the use of a genetic algorithm and density functional theory to study the lowest-energy structures of Agn (silver) clusters ranging in size from n = 3-22 atoms. It finds that Agn clusters from n = 9-16 prefer compact, flat structures, while clusters from n = 19, 21, 22 adopt amorphous packing around a 13-atom icosahedral core. It also identifies competing lowest-energy structures for Ag16, Ag17, and Ag18 between hollow-cage and close-packed configurations. The lowest energy structure of Ag20 is a highly symmetric tetrahedron. These results differ significantly from previous empirical structure predictions.
First principles study on structural and electronic properties of re ag (re= ...Alexander Decker
This article presents a first principles study of the structural, electronic, and mechanical properties of REAg (RE = Y, La, Pr, Er) intermetallic compounds using density functional theory. The results show that these compounds crystallize in the B2 (CsCl-type) structure and are metallic. Lattice constants, bulk moduli, and densities of states are calculated and compared to experimental values where available, showing good agreement. Electronic band structures indicate hybridization between RE d/f states and Ag s/p states near the Fermi level. Partial densities of states of the d orbitals suggest ErAg and YAg are more ductile than LaAg and PrAg due to delocalized Ag d states. Overall
First principles study on structural, electronic, elastic and thermal propert...Alexander Decker
The document discusses a first principles study of the structural, electronic, elastic, and thermal properties of equiatomic MTi compounds (M=Fe, Co, Ni) using density functional theory calculations. The calculations determine the ground state properties, electronic band structures, density of states, and elastic constants of FeTi, CoTi, and NiTi. The results for lattice constants, bulk moduli, and densities of states at the Fermi level are in good agreement with available experimental and theoretical values. NiTi is found to be the most ductile of the three compounds based on calculations of its B/G ratio and Cauchy pressure. The thermal properties, including the Debye temperatures, are also calculated for the first time.
IRJET- Investigation of Structural, Elastic, Electronic and Optical Prope...IRJET Journal
- The document investigates the structural, elastic, electronic, and optical properties of the ternary compound KLiTe using density functional theory calculations.
- The calculated lattice parameters are in good agreement with experimental values. Elastic constants indicate KLiTe is mechanically stable with brittle behavior.
- Electronic structure calculations show KLiTe is a semiconductor with a direct bandgap of 2.37 eV. Optical properties, such as high reflectivity in the UV region, suggest potential use as a coating material.
Study on rare-earth–doped type-I germanium clathratesYang Li
The synthesis of rare-earth clathrates RExBa8xGa16Ge30 is a challenging task. The Group IV clathrates with rare-earth doping are hardly to be experimentally prepared, except Eu clathrate. In the current study, the first-principle method based on the density functional theory was implemented. The effects of the various RE elements doping on the binding energy and chemical reaction drive energy were studied by optimizing the phase structure. The energy calculations suggest that it is difficult to synthesize RE clathrates without Ga doping. The function of Ga doping is to effectively increase the drive chemical reaction in order to synthesize the clathrates. The simulation shows that, besides Eu, other rare-earth elements, such as Sm, Nd, and Yb can also enter cage lattice in the considering of drive energy, thus making it possible to synthesize the (RE,Ba)8Ge30Ga16 clathrates.
The document summarizes research on simulating the surface tension of liquid nickel through molecular dynamics and density functional theory calculations. It describes using embedded atom method interatomic potentials to model nickel, compares calculated density-temperature data to experimental values, and presents a molecular dynamics simulation of a molten nickel nanoparticle in good agreement with experiment. Future work is outlined on modeling nickel-aluminum alloys, oxidation effects, and temperature-dependent interdiffusion at metal-metal interfaces.
Heat Capacity of BN and GaN binary semiconductor under high Pressure-Temperat...IOSR Journals
In this paper, we have calculated the molar heat capacity for cubic zinc blende (cZB) BN and GaN binary semiconductors at high pressure-temperature (PT). For the calculation of heat capacity, we firstly obtained the Debye temperature (ϴD) variation with temperature and at higher temperature it becomes constant with temperature in quasi-harmonic approximation limits. We have also calculated the static Debye temperature (ϴD) from elastic constant for the both BN and GaN binary semiconductors. The elastic constants are calculated from the energy-strain relation using plane wave method in DFT approach. All the calculated results are well consistence with experimental and reported data
Effect of sodium doping on thermal properties of perovskite r mn o3 for poten...Alexander Decker
This document discusses the effect of sodium doping on the thermal properties of perovskite rare earth manganites RMnO3 for potential magnetoelectric applications. It studies the thermal, elastic, and cohesive properties of sodium-doped rare earth manganites R1-xNaxMnO3 (R3+ = La, Pr, Tb) using a modified rigid ion model and atom in molecules theory. It finds that sodium doping increases the A-site cation radius, affecting properties like lattice specific heat, Debye temperature, thermal expansion, bulk modulus, and cohesive energy. These thermal properties are important for determining the compatibility of components in thermoelectric devices and revealing electron-lattice coupling in
The document discusses the use of a genetic algorithm and density functional theory to study the lowest-energy structures of Agn (silver) clusters ranging in size from n = 3-22 atoms. It finds that Agn clusters from n = 9-16 prefer compact, flat structures, while clusters from n = 19, 21, 22 adopt amorphous packing around a 13-atom icosahedral core. It also identifies competing lowest-energy structures for Ag16, Ag17, and Ag18 between hollow-cage and close-packed configurations. The lowest energy structure of Ag20 is a highly symmetric tetrahedron. These results differ significantly from previous empirical structure predictions.
Structural, elastic and electronic properties of 2H- and 4H-SiCIJERA Editor
The structural, five different elastic constants and electronic properties of 2H- and 4H-Silicon carbide (SiC) are investigated by using density functional theory (DFT). The total energies of primitive cells of 2H- and 4H-SiC phases are close to each other and moreover satisfy the condition E2H >E4H. Thus, the 4H-SiC structure appears to be more stable than the 2H- one. The analysis of elastic properties also indicates that the 4H-SiC polytype is stiffer than the 2H structures. The electronic energy bands, the total density of states (DOS) are calculated. The fully relaxed and isotropic bulk modulus is also estimated. The implication of the comparison of our results with the existing experimental and theoretical studies is made.
First principles study of structural, electronic, elastic and mechanical prop...Alexander Decker
This document reports on a first principles study of the structural, electronic, elastic, and mechanical properties of GdSn3 and YbSn3 intermetallic compounds using density functional theory. Key findings include:
1) The calculated ground state properties, such as lattice constants and bulk moduli, agree well with experimental results.
2) Electronic band structure calculations show both compounds are metallic in nature.
3) Elastic constants are reported for the first time, and satisfy the stability criteria for cubic crystals.
4) Both compounds are predicted to be ductile based on their bulk to shear modulus ratio. Young's modulus suggests GdSn3 is stiffer than YbSn3.
Modern electronic structure codes give relatively consistent equations of state. There remain challenges to fully automating electronic structure calculations, such as developing robust materials analysis software to integrate calculations, detecting and correcting errors, and managing scientific workflows. Frameworks like pymatgen, ASE, the Materials Project, AiiDA and Custodian provide modular, reusable tools for high-throughput electronic structure computations and extensive materials analysis capabilities. FireWorks serves as a workflow manager to automate calculations over diverse supercomputing resources. With automation comes large quantities of materials data that can be leveraged for materials design and discovery.
Thermoelectric Power Studies of Ni-Co Nano Ferrites Synthesized By Citrate-Ge...IOSR Journals
This document reports on a study of the thermoelectric power of nickel-cobalt nanoferrites with the chemical formula Ni1-xCoxFe2O4 (where x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) synthesized using the citrate-gel auto combustion method. X-ray diffraction analysis confirmed the formation of a single cubic spinel phase without impurities. Lattice parameters increased with increasing cobalt content due to the larger ionic radius of Co2+ ions compared to Ni2+ ions. Seebeck coefficient measurements from 320K to above the Curie temperature showed that the materials behaved as n-type semiconductors and the
This document discusses the hydrodynamic equations that describe neutral gas and plasma, and how they are modified to become the magnetohydrodynamic (MHD) equations when a conducting fluid is in a magnetic field. It introduces the continuity, momentum, and entropy equations for neutral gas hydrodynamics. It then explains how these are updated to the MHD equations by adding magnetic forces and Ohm's law relating current and fields. The key MHD equations derived include equations for momentum, entropy, and the magnetic field evolving due to motion and diffusion.
Structural, electronic and optical properties of HGS under pressure using FP-...IRJET Journal
This document summarizes a study that uses density functional theory calculations to investigate the structural, electronic, and optical properties of mercury sulfide (HgS) under normal and high pressure conditions. The key findings are:
1) HgS transitions from a zinc blende structure at normal pressure to a rocksalt structure above 16.1 GPa of pressure.
2) Band structure calculations show HgS has a negative direct bandgap of -0.1 eV in the zinc blende phase and a reduced bandgap in the high pressure rocksalt phase.
3) Optical properties like dielectric functions and refractive index are calculated for both phases to better understand HgS's behavior under pressure.
Investigation of mgx sr1 xo mixed alloy under high pressureAlexander Decker
This document reports on research investigating the structural and mechanical properties of the mixed compound MgxSr1-xO under high pressure. An extended interaction potential model was applied that included zero point energy effects to predict phase transition pressures and volume collapses. The model parameters were determined using equilibrium conditions and followed Vegard's law varying linearly with concentration. The results for the mixed compounds were in fair agreement with experimental data generated by applying Vegard's law to the endpoint members MgO and SrO.
Theoretical Investigation on CuxV2-xO5 where x=0, 0.5 Using Density Functiona...IRJET Journal
This document presents a theoretical investigation of V2O5 and Cu0.5V1.5O5 using density functional theory. The calculations were performed using the Vienna Ab-initio Simulation Package. For V2O5, the lattice parameters were underestimated by 1-1.5% compared to experimental values. The bulk modulus was overestimated. V2O5 had a direct bandgap of 2.28 eV and a cohesive energy of 8.67 eV. For Cu0.5V1.5O5, there was no bandgap between the valence and conduction bands, making it conductive. Its cohesive energy was lower than V2O5, indicating V2O5 is more stable.
1) Low-lying excited states of the neutron-rich calcium isotopes 48-52Ca have been studied using gamma-ray spectroscopy following inverse kinematics proton scattering experiments.
2) The energies and strengths of the octupole states in these calcium isotopes are remarkably constant, indicating that these states are dominated by proton excitations of the calcium cores.
3) Specific excited states in 49,51,52Ca were analyzed, and spin and parity assignments were made or supported based on comparisons to previous reaction data and theoretical expectations.
Kirkwood-Buff Theory of Solutions and the Development of Atomistic and Coarse...Nikos Bentenitis
This document discusses the development of atomistic and coarse-grained force fields using the Kirkwood-Buff theory of solutions.
The Kirkwood-Buff theory relates the structure of solutions to their thermodynamic properties through integrals known as Kirkwood-Buff integrals. Several force fields have been developed that reproduce experimental Kirkwood-Buff integrals through adjustments to effective charges. Coarse-grained force fields can also be developed using this approach by mapping molecules to beads and deriving potentials of mean force. The document outlines methods for developing a coarse-grained force field for an ionic liquid in water based on iterative Boltzmann inversion and potential of mean force calculations from all-atom simulations.
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
NANO281 is the University of California San Diego NanoEngineering Department's first course on the application of data science in materials science. It is taught by Professor Shyue Ping Ong of the Materials Virtual Lab (http://www.materialsvirtuallab.org).
Elastic and structural properties of plutonium pnictidesAlexander Decker
This document discusses research into the structural and elastic properties of plutonium pnictides (PuAs and PuSb) under high pressure. An extended interaction potential model is developed to investigate the phase transitions and calculate elastic constants. The model incorporates three-body interactions and zero-point energy effects. Results from the model show good agreement with experimental data for phase transition pressures, volume changes at transition pressures, and elastic constants of PuAs and PuSb. The model provides an improved understanding of the structural behavior and interatomic forces in these materials under high pressure.
A first principle study of pressure induced structural and electronic propert...Alexander Decker
This article summarizes a study that examines the pressure-induced structural and electronic properties of neptunium monobismuthide (NpBi) using first-principles calculations. The authors find that at ambient pressure, NpBi is stable in the NaCl crystal structure. However, they predict that NpBi undergoes a phase transition from the NaCl structure to the CsCl structure at a pressure of around 11 GPa. The calculations also show that NpBi exhibits metallic behavior. The predicted equilibrium lattice parameters and bulk modulus are in good agreement with available experimental data.
Enhancing the working temperature span and refrigerant capacity of two-phase...Universidad de Oviedo
The document discusses enhancing the working temperature span and refrigerant capacity of two-phase composite systems based on amorphous FeZrBCu ribbons. It first introduces the magnetocaloric effect and improving the relative cooling power through composite compounds. It then presents results on the magnetocaloric properties of FeZrBCu amorphous alloys, including their tunable Curie temperatures and large magnetic entropy changes. The advantages of using these alloys in two-phase composite systems are discussed.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijujournal
This document presents an analytical, numerical, and experimental validation of coil voltage in an induction melting process. It describes mathematical models using analytical and numerical methods to represent the induction coil and workpiece. The analytical method uses a series equivalent circuit to calculate coil and workpiece parameters. The numerical method uses finite element analysis and magnetic vector potential formulation to solve field equations. Analytically and numerically computed coil voltages are compared and found to be in good agreement. Experimental results also validate the computed coil voltages at different frequencies. The mathematical models provide a useful tool for coil design and optimization of induction heating processes.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical
methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work
piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard
formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic
vector potential formulation is done and finite element method (FEM) is used to solve the field equations.
Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil
voltage, work piece power are compared and found that they are in good agreement. Analytically and
numerically obtained coil voltages at different frequencies are validated by experimental results. This
mathematical model is useful for coil design and optimization of induction heating process.
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Structural, elastic and electronic properties of 2H- and 4H-SiCIJERA Editor
The structural, five different elastic constants and electronic properties of 2H- and 4H-Silicon carbide (SiC) are investigated by using density functional theory (DFT). The total energies of primitive cells of 2H- and 4H-SiC phases are close to each other and moreover satisfy the condition E2H >E4H. Thus, the 4H-SiC structure appears to be more stable than the 2H- one. The analysis of elastic properties also indicates that the 4H-SiC polytype is stiffer than the 2H structures. The electronic energy bands, the total density of states (DOS) are calculated. The fully relaxed and isotropic bulk modulus is also estimated. The implication of the comparison of our results with the existing experimental and theoretical studies is made.
First principles study of structural, electronic, elastic and mechanical prop...Alexander Decker
This document reports on a first principles study of the structural, electronic, elastic, and mechanical properties of GdSn3 and YbSn3 intermetallic compounds using density functional theory. Key findings include:
1) The calculated ground state properties, such as lattice constants and bulk moduli, agree well with experimental results.
2) Electronic band structure calculations show both compounds are metallic in nature.
3) Elastic constants are reported for the first time, and satisfy the stability criteria for cubic crystals.
4) Both compounds are predicted to be ductile based on their bulk to shear modulus ratio. Young's modulus suggests GdSn3 is stiffer than YbSn3.
Modern electronic structure codes give relatively consistent equations of state. There remain challenges to fully automating electronic structure calculations, such as developing robust materials analysis software to integrate calculations, detecting and correcting errors, and managing scientific workflows. Frameworks like pymatgen, ASE, the Materials Project, AiiDA and Custodian provide modular, reusable tools for high-throughput electronic structure computations and extensive materials analysis capabilities. FireWorks serves as a workflow manager to automate calculations over diverse supercomputing resources. With automation comes large quantities of materials data that can be leveraged for materials design and discovery.
Thermoelectric Power Studies of Ni-Co Nano Ferrites Synthesized By Citrate-Ge...IOSR Journals
This document reports on a study of the thermoelectric power of nickel-cobalt nanoferrites with the chemical formula Ni1-xCoxFe2O4 (where x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) synthesized using the citrate-gel auto combustion method. X-ray diffraction analysis confirmed the formation of a single cubic spinel phase without impurities. Lattice parameters increased with increasing cobalt content due to the larger ionic radius of Co2+ ions compared to Ni2+ ions. Seebeck coefficient measurements from 320K to above the Curie temperature showed that the materials behaved as n-type semiconductors and the
This document discusses the hydrodynamic equations that describe neutral gas and plasma, and how they are modified to become the magnetohydrodynamic (MHD) equations when a conducting fluid is in a magnetic field. It introduces the continuity, momentum, and entropy equations for neutral gas hydrodynamics. It then explains how these are updated to the MHD equations by adding magnetic forces and Ohm's law relating current and fields. The key MHD equations derived include equations for momentum, entropy, and the magnetic field evolving due to motion and diffusion.
Structural, electronic and optical properties of HGS under pressure using FP-...IRJET Journal
This document summarizes a study that uses density functional theory calculations to investigate the structural, electronic, and optical properties of mercury sulfide (HgS) under normal and high pressure conditions. The key findings are:
1) HgS transitions from a zinc blende structure at normal pressure to a rocksalt structure above 16.1 GPa of pressure.
2) Band structure calculations show HgS has a negative direct bandgap of -0.1 eV in the zinc blende phase and a reduced bandgap in the high pressure rocksalt phase.
3) Optical properties like dielectric functions and refractive index are calculated for both phases to better understand HgS's behavior under pressure.
Investigation of mgx sr1 xo mixed alloy under high pressureAlexander Decker
This document reports on research investigating the structural and mechanical properties of the mixed compound MgxSr1-xO under high pressure. An extended interaction potential model was applied that included zero point energy effects to predict phase transition pressures and volume collapses. The model parameters were determined using equilibrium conditions and followed Vegard's law varying linearly with concentration. The results for the mixed compounds were in fair agreement with experimental data generated by applying Vegard's law to the endpoint members MgO and SrO.
Theoretical Investigation on CuxV2-xO5 where x=0, 0.5 Using Density Functiona...IRJET Journal
This document presents a theoretical investigation of V2O5 and Cu0.5V1.5O5 using density functional theory. The calculations were performed using the Vienna Ab-initio Simulation Package. For V2O5, the lattice parameters were underestimated by 1-1.5% compared to experimental values. The bulk modulus was overestimated. V2O5 had a direct bandgap of 2.28 eV and a cohesive energy of 8.67 eV. For Cu0.5V1.5O5, there was no bandgap between the valence and conduction bands, making it conductive. Its cohesive energy was lower than V2O5, indicating V2O5 is more stable.
1) Low-lying excited states of the neutron-rich calcium isotopes 48-52Ca have been studied using gamma-ray spectroscopy following inverse kinematics proton scattering experiments.
2) The energies and strengths of the octupole states in these calcium isotopes are remarkably constant, indicating that these states are dominated by proton excitations of the calcium cores.
3) Specific excited states in 49,51,52Ca were analyzed, and spin and parity assignments were made or supported based on comparisons to previous reaction data and theoretical expectations.
Kirkwood-Buff Theory of Solutions and the Development of Atomistic and Coarse...Nikos Bentenitis
This document discusses the development of atomistic and coarse-grained force fields using the Kirkwood-Buff theory of solutions.
The Kirkwood-Buff theory relates the structure of solutions to their thermodynamic properties through integrals known as Kirkwood-Buff integrals. Several force fields have been developed that reproduce experimental Kirkwood-Buff integrals through adjustments to effective charges. Coarse-grained force fields can also be developed using this approach by mapping molecules to beads and deriving potentials of mean force. The document outlines methods for developing a coarse-grained force field for an ionic liquid in water based on iterative Boltzmann inversion and potential of mean force calculations from all-atom simulations.
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
NANO281 is the University of California San Diego NanoEngineering Department's first course on the application of data science in materials science. It is taught by Professor Shyue Ping Ong of the Materials Virtual Lab (http://www.materialsvirtuallab.org).
Elastic and structural properties of plutonium pnictidesAlexander Decker
This document discusses research into the structural and elastic properties of plutonium pnictides (PuAs and PuSb) under high pressure. An extended interaction potential model is developed to investigate the phase transitions and calculate elastic constants. The model incorporates three-body interactions and zero-point energy effects. Results from the model show good agreement with experimental data for phase transition pressures, volume changes at transition pressures, and elastic constants of PuAs and PuSb. The model provides an improved understanding of the structural behavior and interatomic forces in these materials under high pressure.
A first principle study of pressure induced structural and electronic propert...Alexander Decker
This article summarizes a study that examines the pressure-induced structural and electronic properties of neptunium monobismuthide (NpBi) using first-principles calculations. The authors find that at ambient pressure, NpBi is stable in the NaCl crystal structure. However, they predict that NpBi undergoes a phase transition from the NaCl structure to the CsCl structure at a pressure of around 11 GPa. The calculations also show that NpBi exhibits metallic behavior. The predicted equilibrium lattice parameters and bulk modulus are in good agreement with available experimental data.
Enhancing the working temperature span and refrigerant capacity of two-phase...Universidad de Oviedo
The document discusses enhancing the working temperature span and refrigerant capacity of two-phase composite systems based on amorphous FeZrBCu ribbons. It first introduces the magnetocaloric effect and improving the relative cooling power through composite compounds. It then presents results on the magnetocaloric properties of FeZrBCu amorphous alloys, including their tunable Curie temperatures and large magnetic entropy changes. The advantages of using these alloys in two-phase composite systems are discussed.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic vector potential formulation is done and finite element method (FEM) is used to solve the field equations. Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil voltage, work piece power are compared and found that they are in good agreement. Analytically and numerically obtained coil voltages at different frequencies are validated by experimental results. This mathematical model is useful for coil design and optimization of induction heating process.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijujournal
This document presents an analytical, numerical, and experimental validation of coil voltage in an induction melting process. It describes mathematical models using analytical and numerical methods to represent the induction coil and workpiece. The analytical method uses a series equivalent circuit to calculate coil and workpiece parameters. The numerical method uses finite element analysis and magnetic vector potential formulation to solve field equations. Analytically and numerically computed coil voltages are compared and found to be in good agreement. Experimental results also validate the computed coil voltages at different frequencies. The mathematical models provide a useful tool for coil design and optimization of induction heating processes.
Analytical, Numerical and Experimental Validation of Coil Voltage in Inductio...ijeljournal
This paper presents, mathematical model of induction heating process by using analytical and numerical
methods. In analytical method, series equivalent circuit (SEC) is used to represent induction coil and work
piece. Induction coil and workpiece parameters (resistance and reactance) are calculated by standard
formulas along with Nagaoka correction factors and Bessel functions. In Numerical method, magnetic
vector potential formulation is done and finite element method (FEM) is used to solve the field equations.
Analytically and numerically computed parameters such as equivalent coil resistance, reactance, coil
voltage, work piece power are compared and found that they are in good agreement. Analytically and
numerically obtained coil voltages at different frequencies are validated by experimental results. This
mathematical model is useful for coil design and optimization of induction heating process.
Ihre Aufgabe
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Este manual fornece instruções sobre como preparar e administrar nutrição enteral por sonda nasoenteral, gastrostomia ou jejunostomia de forma segura no domicílio. Detalha os cuidados necessários com cada tipo de sonda, como evitar obstruções e manter a higiene. Também explica como preparar as dietas caseiras ou industriais prescritas e administrá-las corretamente.
This document discusses digital maturity in strategy, servicing, and enablement. It defines strategy as how a company perceives digitization, servicing as digitizing products and customer interactions, and enablement as optimizing internal processes through digital technologies. The document divides companies into two groups: those with an internal focus on enablement and those with a balanced approach across strategy, servicing, and enablement. It provides examples of food/beverage companies innovating through new digital initiatives and platforms. The document emphasizes that digitization opportunities are not limited to product tangibility and that data insights can drive customer understanding.
Presentatie die Hanne Delodder (Huis van Alijn) gaf tijdens Publiek14, de inspiratiedag van Publiek Centraal op 24 maart 2014 in de Gentse Minardschouwburg.
Slides from an in-house workshop I gave at CV&A Consulting in Barcelona. They were looking to include user-centered design activities in their knowledge management and e-learning projects.
The White House website provides information about the President, Vice President and their administration. It features details on policy initiatives, visits, speeches and other activities of the executive branch. Visitors can learn about the history and functions of the White House as well as stay up to date on the current administration's priorities and actions.
Alimentando o bebe com fissura labial ou fenda palatina (espanhol)Creche Segura
Este documento proporciona instrucciones para alimentar a un bebé con hendidura del labio o paladar. Explica cómo usar tres tipos de biberones diseñados especialmente para bebés con hendiduras, incluidos el Enfamil Cleft Palate Nurser, el Haberman Special Needs Bottle y el Pigeon Bottle. También ofrece consejos generales sobre la posición del bebé, el ritmo de la alimentación y signos de que la alimentación está yendo bien. El objetivo es ayudar a los padres a alimentar con éxito
Unit tests were running slowly and failing randomly after 1,050 tests due to a memory leak. Using the node-memwatch module, a memory leak was detected when the heap usage increased for five consecutive garbage collections. A deeper analysis with node-heapdump revealed that almost half a gigabyte of memory was being used to store String objects, which was traced to the same WSDL file being loaded multiple times without being garbage collected.
Costumamos ver as metodologias do Service Design aplicadas principalmente na criação de novos serviços ou startups. Neste encontro, conversaremos sobre como essas ferramentas podem ser usadas para o redesign de serviços já existentes e na manutenção deles.
A partir de um caso real, debateremos sobre os desafios e os aprendizados para utilizar os processos de colaboração, cocriação e a empatia dentro de uma grande corporação, com diversas equipes e uma cultura consolidada.
The document discusses the importance of facility planning and siting to prevent incidents and minimize risks. It outlines factors to consider for external and internal site location, including effects on the community, environment and operations. Examples of major chemical plant incidents are provided, demonstrating consequences of fires, explosions and toxic releases. The planning process involves risk assessments of hazards, controls to reduce risk, and following industry standards.
The document discusses quality planning and project kickoff, including defining quality, quality planning processes, quality gurus like Deming and Juran, frameworks for quality like ISO and Six Sigma, core quality concepts around stakeholder satisfaction and process management, and planning for a project kickoff meeting. It provides an overview of important concepts for ensuring project quality and setting the stage for a successful project launch.
Table19's Remarkable Round Up of Cannes Lions 2016Table19
The Cannes Lions festival was founded in 1954 and sees over 15,000 delegates attend annually. In 2016, Samsung was named Creative Marketer of the Year. A new Entertainment Lions category was added to recognize creativity that blurs the lines between advertising and entertainment. Technological achievements like Google DeepMind's AlphaGo and ING Bank's The Next Rembrandt project were highlights. Direct marketing and socially responsible campaigns also took many innovative forms at the 2016 Cannes Lions festival.
EVALUATING STRUCTURAL, OPTICAL & ELECTRICAL CHARACTERIZATION OF ZINC CHALCOGE...Editor IJCATR
To evaluate the structural, optical & electrical properties of the zinc chalcogenides (ZnO, ZnS, ZnSe & ZnTe), the Full
Potential Linearized – Augumented Plane Wave plus Local Orbits (FP – LAPW+lo) method. For the purpose of exchange-correlation
energy (Exc) determination in Kohn–Sham calculation, the standard local density approximation (LDA) formalism has been utilized.
Murnaghan’s equation of state (EOS) has been used for volume optimization by minimizing the total energy with respect to the unit
cell volume. With the result of electronic density of states (DOS), the structural, optical and electrical properties of Zinc chalcogenides
have been calculated. The second derivative of energy, as a function of lattice strain has been successfully used to estimate the elastic
constants of these binary compounds. The results are in good agreement with other theoretical calculations as well as available
experimental data.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
The document summarizes research on the polarizability of donors in spherical gallium arsenide (GaAs) quantum dots (QDs) under an applied electric field. The author uses an effective mass approximation and variational method to calculate:
1) The binding energy of donors at different positions within the QD and as a function of QD size.
2) The polarizability of donors in the QD under an applied electric field. The polarizability is found to be several orders of magnitude higher than hydrogen atoms.
3) The results agree with previous theoretical studies. The binding energy increases as QD size decreases.
Prediction of electronic and magnetic properties of Full Heusler Alloy – Ir2CrAlIOSR Journals
This document summarizes a study that used density functional theory calculations to predict the structural, electronic, and magnetic properties of the full Heusler alloy Ir2CrAl. The calculations found that Ir2CrAl has:
1) A lattice constant of 5.9648 Å after structural optimization, with a bulk modulus of 270.9 GPa.
2) Half-metallic behavior with 100% spin polarization at the Fermi level, due to an indirect band gap of 0.3 eV in the minority spin channel.
3) Ferromagnetic ordering with a total magnetic moment of 3 μB per formula unit, in agreement with Slater-Pauling rules for Heusler alloys.
The document summarizes key information about the CdGa2S4 semiconductor. It belongs to the ordered vacancy compound family, which contains direct bandgap materials less than 4 eV that can be used in optoelectronic devices. CdGa2S4 has a defect chalcopyrite structure at ambient conditions and undergoes a phase transition to a disordered rocksalt structure above 18.8 GPa. First-principles density functional theory calculations were performed to investigate the structural stability and electronic properties of both phases under varying pressures. The results show that the defect chalcopyrite phase is more stable at lower pressures and becomes metallic above the transition pressure where the structures change.
Plasmon Enhanced Internal Quantum Efficiency of CdSe/ZnS Quantum Dotsijrap
The effects of surface plasmon oscillations on the radiative recombination rate and internal quantum efficiency of silver coated CdSe/ZnS quantum dots imbedded in quartz matrix is studied theoretically and
numerically. The analysis is carried out by introducing the local field enhancement factor for the description of the dielectric function of the quantum dots together with the modified Drude model for the metal-coat that takes into account the effects of interband transitions and the size dependent damping
parameter. It is found out that the internal quantum efficiency of photoluminescence emission of the metalcoated CdSe/ZnS quantum dots is enhanced by about 5-folds compared with the quantum dots without metal-coat. Moreover, increasing the metal fraction of the coated CdSe/ZnS quantum dots from 0.80 to 0.92 results in a significant increase of the intensity that is accompanied by a blue-shift of the quantum efficiency curves. The results obtained can be utilized in the design and fabrication of optoelectronic devices that require high intensity of photoluminescence emission.
Theoretical study of electronic properties of some aromatic ringsAlexander Decker
The document summarizes a theoretical study on the electronic properties of aromatic rings containing nitrogen atoms. Density functional theory was used to calculate properties of pyridine, pyrimidine, pyrazine and pyridazine, with nitrogen in different positions on a benzene ring. Key results showed adding nitrogen decreased energy gaps and improved electronic properties compared to benzene. Calculated properties included optimized structures, total energies, electronic states, energy gaps, ionization potentials, electron affinities, and vibration frequencies, with B3LYP/DFT showing good agreement with available experimental data.
High pressure structural properties of rare earth antimonideAlexander Decker
1) The document investigates the high-pressure structural phase transition of rare-earth antimonide DySb using a three-body potential model with electronic polarizability.
2) This model predicts a first-order phase transition from the NaCl (B1) structure to the CsCl (B2) structure in DySb at 22.6 GPa, with a 3.8% volume collapse.
3) The predicted transition pressure and volume change are in good agreement with available experimental data.
A Nano Capacitor Including Graphene Layers Composed with Doped Boron and Nitr...CrimsonPublishersRDMS
A Nano Capacitor Including Graphene Layers Composed with Doped Boron and Nitrogen by Majid Monajjemi* in Crimson Publishers: Peer Reviewed Material Science Journals
IOSR Journal of Applied Physics (IOSR-JAP) is an open access international journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This document describes a study that performed computer simulations of EPR spectra of Cu2+ in Cd2(NH4)2(SO4)3 single crystals at different temperatures. The simulations were done for the low magnetic field direction (M=-3/2) using an integrated Lorentzian line shape function involving three variables. The normalized intensity was found to decrease with increasing temperature, showing a phase transition around 195 K. The activation energy was also found to vary with temperature in a similar pattern as the intensity. The resonance field and linewidths were found to depend on temperature as sums of polynomials and exponential terms.
COHESIVE ENERGY AND SPECTROSCOPIC CONSTANTS OF HEAVY METAL HALIDES AND SOME C...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
This document discusses theoretical and experimental studies on viologen-containing 1,1'-binaphthyls as potential near-infrared chiroptically switching materials. Theoretical modeling was used to correlate chiroptical properties with molecular geometry, showing maximal properties for a twisting angle of 60° and interchromophoric distance of 3.9 nm. Two chiral molecules containing viologen groups attached to a 1,1'-binaphthyl core through short spacers were synthesized and showed strong circular dichroism bands in the visible and near-infrared regions upon electrochemical reduction, demonstrating their potential as chiroptical switches. The cyclic molecule showed stronger chiroptical properties than the open-ring analogue.
This document presents the theory and simulation of EPR spectra of Cu2+ ions in Cd2(NH4)2(SO4)3 single crystals at different temperatures ranging from 15-180K. The author derives an expression for the derivative line shape function of the EPR spectra accounting for the orthorhombic Jahn-Teller effect of Cu2+. Computer simulation is performed by fitting the line shape function to the observed spectra. The simulation shows excellent agreement and allows extraction of spectroscopic parameters like g-values and hyperfine coupling constants. Analysis of the temperature-dependent spectra provides insight into the Jahn-Teller splitting and dynamics of Cu2+ in this system.
1) The study investigated the effect of adding zirconium oxide nanoparticles to carbon black electrode materials on surface morphology and electrochemical performance.
2) Scanning electron microscopy showed that adding nanoparticles partially filled gaps between carbon black particles, increasing the specific surface area available for charge storage.
3) Electrochemical analysis found that increasing nanoparticle content initially increased total charge storage due to higher surface area and pseudocapacitive charge storage, but further increases reduced performance due to higher electrode resistance.
The FTIR and FT Raman spectra of 1-4-Dichloro-2-NitroBenzene (14DC2NB) have been recorded in the region 4000-400 cm-1 and 3500-50 cm-1 respectively. The optimized geometry ,frequency and intensity of the vibrational bands of 1-4-Dichloro-2-NitroBenzene (14DC2NB) was obtained by the Density functional theory (DFT)using the basis set 6-31g(d,p). The harmonic vibrational frequencies were calculated and scaled values have been compared with experimental FT-IR and FT-Raman spectra. The Calculated and Observed frequencies are found to be in good agreement. UV-Visible spectrum of the compound was recorded, the electronic properties and HOMO - LUMO energies were calculated by Time Dependent DFT (TD-DFT) approach. A detailed interpretation of the infrared and Raman spectra were also reported based on Potential Energy Distribution (PED). The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of 14DC2NB were calculated using the GIAO approach by applying B3LYP method. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The Chemical reactivity and Thermodynamic properties of 14DC2NB at different temperatures were also calculated
SURFACE POLARITONS IN GAAS/ALGAAS/LH HETROJUNCTION STRUCTURE IN A HIGH MAGNET...ijrap
This document summarizes research on surface polaritons in a GaAs/AlGaAs heterojunction structure with a left-handed material upper layer in a high magnetic field. The dispersion characteristics of surface polaritons are investigated using dielectric constants of GaAs and AlGaAs layers and a defined AlGaAs thickness. Electromagnetic waves are derived for the structure considering transverse magnetic and electric waves. Boundary conditions at layer interfaces and a surface current lead to a dispersion equation relating frequency, wave vector, conductivity, and layer properties. Calculated dispersion curves show frequency increases significantly when a left-handed upper layer is used compared to a dielectric layer.
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Structural and magnetic properties on F-doped LiVO2 with two-dimensional tria...Yang Li
The layered oxide LiVO2 recently has received more attention due to its interesting structural and magnetic behaviors involving the two-dimensional magnetic frustration in these systems. We synthesized a series of F-doped LiVO2 samples, and reported the F-doping effect on the structure and transition temperature Tt. The samples LiVO2-xFx (x=0, 0.1, 0.2 and 0.3) were characterized by X-ray diffraction, scanning electron microscope (SEM), differential scanning calorimetry (DSC), magnetic susceptibility and specific heat measurement. The structural analysis shows that with increasing x, the ratio of lattice parameter c/a increasing, i.e. in the a-b plane the lattice is compressed while in the c-axis direction the lattice expands. The DSC measurements show that a first-order phase transition happens at around 500 K, and the thermal hysteresis around phase transition temperature Tt increases with increasing x. Substitution of O with F ions results in a change of two dimensional characteristics and the distortion of the VO6 block in structure, which significantly influence the magnetic ordering transition temperature Tt.
Similar to First principles study of electronic, elastic and thermal properties of b2 type re cd (re =la, ce and pr) compounds (20)
Abnormalities of hormones and inflammatory cytokines in women affected with p...Alexander Decker
Women with polycystic ovary syndrome (PCOS) have elevated levels of hormones like luteinizing hormone and testosterone, as well as higher levels of insulin and insulin resistance compared to healthy women. They also have increased levels of inflammatory markers like C-reactive protein, interleukin-6, and leptin. This study found these abnormalities in the hormones and inflammatory cytokines of women with PCOS ages 23-40, indicating that hormone imbalances associated with insulin resistance and elevated inflammatory markers may worsen infertility in women with PCOS.
A usability evaluation framework for b2 c e commerce websitesAlexander Decker
This document presents a framework for evaluating the usability of B2C e-commerce websites. It involves user testing methods like usability testing and interviews to identify usability problems in areas like navigation, design, purchasing processes, and customer service. The framework specifies goals for the evaluation, determines which website aspects to evaluate, and identifies target users. It then describes collecting data through user testing and analyzing the results to identify usability problems and suggest improvements.
A universal model for managing the marketing executives in nigerian banksAlexander Decker
This document discusses a study that aimed to synthesize motivation theories into a universal model for managing marketing executives in Nigerian banks. The study was guided by Maslow and McGregor's theories. A sample of 303 marketing executives was used. The results showed that managers will be most effective at motivating marketing executives if they consider individual needs and create challenging but attainable goals. The emerged model suggests managers should provide job satisfaction by tailoring assignments to abilities and monitoring performance with feedback. This addresses confusion faced by Nigerian bank managers in determining effective motivation strategies.
A unique common fixed point theorems in generalized dAlexander Decker
This document presents definitions and properties related to generalized D*-metric spaces and establishes some common fixed point theorems for contractive type mappings in these spaces. It begins by introducing D*-metric spaces and generalized D*-metric spaces, defines concepts like convergence and Cauchy sequences. It presents lemmas showing the uniqueness of limits in these spaces and the equivalence of different definitions of convergence. The goal of the paper is then stated as obtaining a unique common fixed point theorem for generalized D*-metric spaces.
A trends of salmonella and antibiotic resistanceAlexander Decker
This document provides a review of trends in Salmonella and antibiotic resistance. It begins with an introduction to Salmonella as a facultative anaerobe that causes nontyphoidal salmonellosis. The emergence of antimicrobial-resistant Salmonella is then discussed. The document proceeds to cover the historical perspective and classification of Salmonella, definitions of antimicrobials and antibiotic resistance, and mechanisms of antibiotic resistance in Salmonella including modification or destruction of antimicrobial agents, efflux pumps, modification of antibiotic targets, and decreased membrane permeability. Specific resistance mechanisms are discussed for several classes of antimicrobials.
A transformational generative approach towards understanding al-istifhamAlexander Decker
This document discusses a transformational-generative approach to understanding Al-Istifham, which refers to interrogative sentences in Arabic. It begins with an introduction to the origin and development of Arabic grammar. The paper then explains the theoretical framework of transformational-generative grammar that is used. Basic linguistic concepts and terms related to Arabic grammar are defined. The document analyzes how interrogative sentences in Arabic can be derived and transformed via tools from transformational-generative grammar, categorizing Al-Istifham into linguistic and literary questions.
A time series analysis of the determinants of savings in namibiaAlexander Decker
This document summarizes a study on the determinants of savings in Namibia from 1991 to 2012. It reviews previous literature on savings determinants in developing countries. The study uses time series analysis including unit root tests, cointegration, and error correction models to analyze the relationship between savings and variables like income, inflation, population growth, deposit rates, and financial deepening in Namibia. The results found inflation and income have a positive impact on savings, while population growth negatively impacts savings. Deposit rates and financial deepening were found to have no significant impact. The study reinforces previous work and emphasizes the importance of improving income levels to achieve higher savings rates in Namibia.
A therapy for physical and mental fitness of school childrenAlexander Decker
This document summarizes a study on the importance of exercise in maintaining physical and mental fitness for school children. It discusses how physical and mental fitness are developed through participation in regular physical exercises and cannot be achieved solely through classroom learning. The document outlines different types and components of fitness and argues that developing fitness should be a key objective of education systems. It recommends that schools ensure pupils engage in graded physical activities and exercises to support their overall development.
A theory of efficiency for managing the marketing executives in nigerian banksAlexander Decker
This document summarizes a study examining efficiency in managing marketing executives in Nigerian banks. The study was examined through the lenses of Kaizen theory (continuous improvement) and efficiency theory. A survey of 303 marketing executives from Nigerian banks found that management plays a key role in identifying and implementing efficiency improvements. The document recommends adopting a "3H grand strategy" to improve the heads, hearts, and hands of management and marketing executives by enhancing their knowledge, attitudes, and tools.
This document discusses evaluating the link budget for effective 900MHz GSM communication. It describes the basic parameters needed for a high-level link budget calculation, including transmitter power, antenna gains, path loss, and propagation models. Common propagation models for 900MHz that are described include Okumura model for urban areas and Hata model for urban, suburban, and open areas. Rain attenuation is also incorporated using the updated ITU model to improve communication during rainfall.
A synthetic review of contraceptive supplies in punjabAlexander Decker
This document discusses contraceptive use in Punjab, Pakistan. It begins by providing background on the benefits of family planning and contraceptive use for maternal and child health. It then analyzes contraceptive commodity data from Punjab, finding that use is still low despite efforts to improve access. The document concludes by emphasizing the need for strategies to bridge gaps and meet the unmet need for effective and affordable contraceptive methods and supplies in Punjab in order to improve health outcomes.
A synthesis of taylor’s and fayol’s management approaches for managing market...Alexander Decker
1) The document discusses synthesizing Taylor's scientific management approach and Fayol's process management approach to identify an effective way to manage marketing executives in Nigerian banks.
2) It reviews Taylor's emphasis on efficiency and breaking tasks into small parts, and Fayol's focus on developing general management principles.
3) The study administered a survey to 303 marketing executives in Nigerian banks to test if combining elements of Taylor and Fayol's approaches would help manage their performance through clear roles, accountability, and motivation. Statistical analysis supported combining the two approaches.
A survey paper on sequence pattern mining with incrementalAlexander Decker
This document summarizes four algorithms for sequential pattern mining: GSP, ISM, FreeSpan, and PrefixSpan. GSP is an Apriori-based algorithm that incorporates time constraints. ISM extends SPADE to incrementally update patterns after database changes. FreeSpan uses frequent items to recursively project databases and grow subsequences. PrefixSpan also uses projection but claims to not require candidate generation. It recursively projects databases based on short prefix patterns. The document concludes by stating the goal was to find an efficient scheme for extracting sequential patterns from transactional datasets.
A survey on live virtual machine migrations and its techniquesAlexander Decker
This document summarizes several techniques for live virtual machine migration in cloud computing. It discusses works that have proposed affinity-aware migration models to improve resource utilization, energy efficient migration approaches using storage migration and live VM migration, and a dynamic consolidation technique using migration control to avoid unnecessary migrations. The document also summarizes works that have designed methods to minimize migration downtime and network traffic, proposed a resource reservation framework for efficient migration of multiple VMs, and addressed real-time issues in live migration. Finally, it provides a table summarizing the techniques, tools used, and potential future work or gaps identified for each discussed work.
A survey on data mining and analysis in hadoop and mongo dbAlexander Decker
This document discusses data mining of big data using Hadoop and MongoDB. It provides an overview of Hadoop and MongoDB and their uses in big data analysis. Specifically, it proposes using Hadoop for distributed processing and MongoDB for data storage and input. The document reviews several related works that discuss big data analysis using these tools, as well as their capabilities for scalable data storage and mining. It aims to improve computational time and fault tolerance for big data analysis by mining data stored in Hadoop using MongoDB and MapReduce.
1. The document discusses several challenges for integrating media with cloud computing including media content convergence, scalability and expandability, finding appropriate applications, and reliability.
2. Media content convergence challenges include dealing with the heterogeneity of media types, services, networks, devices, and quality of service requirements as well as integrating technologies used by media providers and consumers.
3. Scalability and expandability challenges involve adapting to the increasing volume of media content and being able to support new media formats and outlets over time.
This document surveys trust architectures that leverage provenance in wireless sensor networks. It begins with background on provenance, which refers to the documented history or derivation of data. Provenance can be used to assess trust by providing metadata about how data was processed. The document then discusses challenges for using provenance to establish trust in wireless sensor networks, which have constraints on energy and computation. Finally, it provides background on trust, which is the subjective probability that a node will behave dependably. Trust architectures need to be lightweight to account for the constraints of wireless sensor networks.
This document discusses private equity investments in Kenya. It provides background on private equity and discusses trends in various regions. The objectives of the study discussed are to establish the extent of private equity adoption in Kenya, identify common forms of private equity utilized, and determine typical exit strategies. Private equity can involve venture capital, leveraged buyouts, or mezzanine financing. Exits allow recycling of capital into new opportunities. The document provides context on private equity globally and in developing markets like Africa to frame the goals of the study.
This document discusses a study that analyzes the financial health of the Indian logistics industry from 2005-2012 using Altman's Z-score model. The study finds that the average Z-score for selected logistics firms was in the healthy to very healthy range during the study period. The average Z-score increased from 2006 to 2010 when the Indian economy was hit by the global recession, indicating the overall performance of the Indian logistics industry was good. The document reviews previous literature on measuring financial performance and distress using ratios and Z-scores, and outlines the objectives and methodology used in the current study.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
AI 101: An Introduction to the Basics and Impact of Artificial IntelligenceIndexBug
Imagine a world where machines not only perform tasks but also learn, adapt, and make decisions. This is the promise of Artificial Intelligence (AI), a technology that's not just enhancing our lives but revolutionizing entire industries.
Maruthi Prithivirajan, Head of ASEAN & IN Solution Architecture, Neo4j
Get an inside look at the latest Neo4j innovations that enable relationship-driven intelligence at scale. Learn more about the newest cloud integrations and product enhancements that make Neo4j an essential choice for developers building apps with interconnected data and generative AI.
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
Infrastructure Challenges in Scaling RAG with Custom AI modelsZilliz
Building Retrieval-Augmented Generation (RAG) systems with open-source and custom AI models is a complex task. This talk explores the challenges in productionizing RAG systems, including retrieval performance, response synthesis, and evaluation. We’ll discuss how to leverage open-source models like text embeddings, language models, and custom fine-tuned models to enhance RAG performance. Additionally, we’ll cover how BentoML can help orchestrate and scale these AI components efficiently, ensuring seamless deployment and management of RAG systems in the cloud.
For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/building-and-scaling-ai-applications-with-the-nx-ai-manager-a-presentation-from-network-optix/
Robin van Emden, Senior Director of Data Science at Network Optix, presents the “Building and Scaling AI Applications with the Nx AI Manager,” tutorial at the May 2024 Embedded Vision Summit.
In this presentation, van Emden covers the basics of scaling edge AI solutions using the Nx tool kit. He emphasizes the process of developing AI models and deploying them globally. He also showcases the conversion of AI models and the creation of effective edge AI pipelines, with a focus on pre-processing, model conversion, selecting the appropriate inference engine for the target hardware and post-processing.
van Emden shows how Nx can simplify the developer’s life and facilitate a rapid transition from concept to production-ready applications.He provides valuable insights into developing scalable and efficient edge AI solutions, with a strong focus on practical implementation.
GraphRAG for Life Science to increase LLM accuracyTomaz Bratanic
GraphRAG for life science domain, where you retriever information from biomedical knowledge graphs using LLMs to increase the accuracy and performance of generated answers
In the rapidly evolving landscape of technologies, XML continues to play a vital role in structuring, storing, and transporting data across diverse systems. The recent advancements in artificial intelligence (AI) present new methodologies for enhancing XML development workflows, introducing efficiency, automation, and intelligent capabilities. This presentation will outline the scope and perspective of utilizing AI in XML development. The potential benefits and the possible pitfalls will be highlighted, providing a balanced view of the subject.
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First principles study of electronic, elastic and thermal properties of b2 type re cd (re =la, ce and pr) compounds
1. Advances in Physics Theories and Applications www.iiste.org
ISSN 2224-719X (Paper) ISSN 2225-0638 (Online)
Vol.19, 2013 - Selected from International Conference on Recent Trends in Applied Sciences with Engineering Applications
149
First Principles Study of Electronic, Elastic and Thermal
Properties of B2-type RECd (RE =La, Ce and Pr) Compounds
Hansa Devi1
, Gitanjali Pagare1*
, Sunil Singh Chouhan1
and Sankar P. Sanyal2
1
Department of Physics Government M. L. B. Girls P. G. College, Bhopal 462-002 India
2
Department of Physics, Barkatullah University Bhopal 462-026 India
*Corresponding Author E-mail: gita_pagare@yahoo.co.in
Abstract
The electronic, elastic and thermal properties of RECd (RE =La, Ce and Pr) intermetallic compounds
crystallizing in B2-type structure have been studied using first principles density functional theory within
generalized gradient approximation (GGA), and the local spin density approximation (LSDA) for the exchange
correlation potential. From energy band structure and density of states we found that these intermetallics are
metallic in nature. The thermal and mechanical properties are predicted from the calculated values of elastic
constants. The ductility of these compounds is determined by calculating the bulk to shear ratio B/GH. Our
calculated results indicate that PrCd is most ductile amongst all the RECd compounds. To the best of our
knowledge this is the first theoretical prediction of the elastic properties of these compounds.
Keywords: Intermetallics, Density Functional Theory, Elastic Constant, Ductility.
1. Introduction
Rare earth intermetallics that contain rare earth element and transition element have been extensively studied for
several decades because of their appealing mechanical properties such as high oxidation resistance, high stiffness,
high strength, ductility and attractive high temperature [1-5] which makes them promising high temperature
structural material for automobile, aviation and aerospace application. The energy dispersive powder X-ray
diffraction measurements of some LnM (Ln=La, Ce, Nd and Gd; M= Cu, Ag and Zn) compounds have been
performed by Degtyareva et a.l [6]. Fujii et al. [7] have studied the magnetic properties of CeCd single crystal.
Sousa et al. [8] have explained that there are three kinds of phase transition in PrCd: a structural phase transition
at Ts= 125 K, an antiferromagnetic to paramagnetic transition at TN =40 K and an unknown phase transition at Tt
=20K Magnetic and structural phase transition of CeCd at hydrostatic pressure has been studied by Kadomatsu et
al. [9]. 1ndelli et al. [10] have studied experimental lattice parameter of LaCd, CeCd and PrCd by X-ray
diffraction technique. The RECd (RE=La, Ce and Pr) intermetallics crystallize in cubic cesium chloride structure
(B2–phase, Pm3m, Space Group, 221) [11]. In the B2 RECd intermetallics f–electrons present in RE specie, play
a vital role in exploring structural and electronic properties. Therefore, it becomes significant to understand the
electronic properties of this class of intermetallics. To the best of our knowledge the structural and electronic
properties of RECd intermetallics at normal as well as at high pressure have not been extensively studied and are
yet to be explored in detail. We do not find any comprehensive study related to elastic, mechanical and thermal
properties such as Young modulus and Poisson ratio, Debye temperature etc in the literature so far. So a
comprehensive theoretical calculation of the electronic structure and elastic properties for this RECd (RE =La,
Ce and Pr) compounds based on density functional theory (DFT) is performed in the present work.
In the present work, non spin polarized calculations are performed to investigate the fundamental properties of
the LaCd, while spin polarized calculations are done for CeCd and PrCd compounds with B2 structure using
generalized gradient approximation (GGA) of PERDEW, BURKE and ERNZRHOF (PBE) [11] and Local spin
density approximation LSDA approximations[12]. The rest of the paper is organized as follows: section 2 deals
with the method of calculations which is employed for the electronic and elastic properties of the RECd
intermetallic compounds. In Section 3, we present the results and compared them with the other experimental
results. Finally, we present the conclusion in Section 4.
2. Method of Calculation
The calculations are performed using the full potential linearized augment plane wave method as implemented in
WIEN2k package [13]. In order to achieve the energy eigen value convergence, we expand the basis function up
to RMT*Kmax= 7 where RMT is the smallest atomic sphere radius in the unit cell and Kmax gives the magnitude of
the largest K vector in the plane wave expansion. The valence wave functions inside the spheres are expanded up
to lmax =10 while the charge density is Fourier expanded up to Gmax= 12. A dense mesh of 1000 k points is used
and the tetrahedral method has been employed for the Brillouin zone integration. The total energies are
calculated as a function of volume and fitted to Birch equation of state [14] to obtain the ground state properties.
The elastic constants play an important role in determination of the strength, brittleness/ductility, and hardness of
materials. The traditional mechanical stability conditions in cubic crystals on the elastic constants are known as
2. Advances in Physics Theories and Applications www.iiste.org
ISSN 2224-719X (Paper) ISSN 2225-0638 (Online)
Vol.19, 2013 - Selected from International Conference on Recent Trends in Applied Sciences with Engineering Applications
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C11 - C12 > 0, C11 >0, C44 > 0, C12 < B < C11. Our calculated elastic constants presented in Table 1 obey these
stability conditions. In the present study the elastic constants are calculated by using the method developed by
Charpin and integrated incorporated in WIEN2k package [13].
One of the standard methods to calculate the Debye temperature is from elastic constants data, since θD may be
estimated from the following equation [15, 16]:
m
aB
D v
V
n
K
h 3
1
4
3
=
π
θ
where h is a Plank’s constant, kB is Boltzmann’s constant; Va is the average atomic volume.
3. Results and Discussions
3.1 Electronic Properties
For the ground state properties of RECd (RE=La, Ce and Pr) intermetallic compounds the total energies are
calculated as a function of volume in B2 phase. The calculated total energies are fitted to the Birch equation of
state [14] to determine the ground state properties like lattice constant (a0), bulk modulus (B), its pressure
derivative (B')and magnetic moments (µB) which are listed in Table 1 and compared with the available
experimental results. We have calculated partial density of states (DOS) along with the total DOS at Fermi level
(EF) for all the RECd (RE= La, Ce and Pr) intermetallics under ambient conditions and depicted in Fig. 1(a)-(e)
The calculated electronic band structures (BS) along the principle symmetry directions of RECd compounds are
presented in the Fig.2 (a) – (c) where Fermi level is considered at origin. For all RECd compounds the lowest
lying energy bands are due to RE ‘p’ states as shown in the Fig 1(a)-(e). For LaCd, the Density of states (DOS)
at the Fermi level is mainly due to the ‘d ’ states of La, which hybridize with ‘s’ and ‘d’ states of Cd. However,
‘f ’ states of La can be seen above the Fermi level near 2 eV, which might be due to the charge leakage during
the hybridization of ‘d ’ states of La, with ‘s’ and ‘d’ states of Cd.
As CeCd and PrCd being the magnetic compound, we performed spin polarized ferromagnetic calculations for
them. For CeCd the ‘f’ like states of Ce in majority spin channel are located at the Fermi Level. For minority
spin channel, this state get shift above to the Fermi level near 0.45eV in conduction band. Similarly for PrCd, we
get a finite DOS at the Fermi level which is due to the mixing of ‘f’ states of Pr with the ‘p’ state of Cd and ‘d’
state of Pr for spin up channel while for spin down these states are situated near 1.4eV above the Fermi Level.
From DOS and BS it is clear that metallic behaviour in CeCd and PrCd are mainly due to the 4f orbital electrons
of Ce and Pr while in LaCd it is due to 5d orbital electron states. The number of density of states at Fermi level
N (EF) for LaCd CeCd and PrCd are 0.06, 7.75 and 28.709 states /eV respectively.
3.3 Elastic Properties
The elastic constants are important characteristic parameters of solids. The investigation of them is essential to
understand many of their physical properties. We have calculated the elastic constants of the RECd compounds
at ambient pressure by using the method developed by Charpin and integrated it in the WIEN2k package [13]. It
is noticeable from Table 1, that our calculated elastic constants satisfied the stability criteria. To the best of our
knowledge, no experimental or theoretical values of elastic moduli for the studied compounds are available in
literature
3.4 Mechanical properties
Elastic constants can be used to determine mechanical properties such as Young’s modulus (E), shear modulus
(G), Poisson’s ratio (σ), anisotropic ratio (A), for useful applications. We have calculated these properties of
RECd compound and presented in Table 3. The shear modulus GH describes the material’s response to shearing
strain using the Voigt- Reuss-Hill (VRH) method [16-18], the effective modulus for the polycrystals could be
approximated by the arithmetic mean of the two well known bounds for monocrystals. The bulk modulus and
Hill shear modulus GH is defined as:
)2(
3
1
1211 CCB += and
( )
2
34
)(5
5
3
121144
121144441211
CCC
CCCCCC
GH
−+
−
+
+−
=
where Hill shear modulus GH is the average sum of Voigt shear modulus (GV)and Reuss shear modulus (GR) The
Young’s modulus (E) describes the material's response to linear strain, such that,
E=
9 BG H
3B+GH
The Poisson’s ratio (σ) is given as:
3. Advances in Physics Theories and Applications www.iiste.org
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Vol.19, 2013 - Selected from International Conference on Recent Trends in Applied Sciences with Engineering Applications
151
( )H
H
G+
=σ
3B2
2G3B −
The calculated value of Poisson’s ratio for LaCd, CeCd and PrCd are 0.24, 0.28 and 0.33 respectively, and is
given in Table 2. The value of Poisson’s ratio (σ), found to be ≈ 0.1 in covalent material and ≈ 0.33 in metallic
material [19, 21].
Another important parameter is the elastic anisotropic factor A, which gives measure of the degree of elastic
anisotropy in solid, and is given as:
1211
442C
CC
=A
−
For an ideal isotropic system, A is unity and deviation from unity measures the amount of elastic anisotropy. The
calculated anisotropy factors for CeCd and PrCd compounds are found to be greater than one, while for LaCd it
is found to be less than one, hence these compounds are not elastically isotropic. As suggested by Pugh [22], a
material will be ductile if B/GH >1.75. From Table 2, it can be seen that amongst RECd compounds, the
calculated values of B/GH for CeCd and PrCd are found to be 1.95 and 2.64, which indicate that these
compounds show ductile nature while for LaCd it is found to be 1.41 indicating brittle nature. The Young’s
modulus (E) and Poisson’s ratio (σ) are very important properties for industrial applications. The Young’s
modulus (E), the ratio of the tensile stress to the corresponding tensile strain, is required to provide information
about the measure of the stiffness of the solids. LaCd has higher value of Young’s modulus among RECd
indicating LaCd is stiffer than CeCd and PrCd. The hardness of a material can be determined more accurately by
using the Bulk modulus. The calculated value of Bulk moduli increases from PrCd to LaCd indicating that LaCd
is hardest and least compressible than the other RECd compounds. Pettifor [23] suggested the bond character of
cubic compounds with respect to their Cauchy pressure (C12–C44). The negative value of Cauchy’s Pressure
shows their brittle nature. The calculated value of Cauchy’s pressure for LaCd is negative while that of CeCd
and PrCd are negative.
3.5 Thermal properties
We have calculated average sound velocities, Debye temperature as well as the density for these compounds in
B2 phase by using the calculated elastic constants which are given in Table 2. The Debye temperature defines a
division line between quantum mechanical and classical behaviour of phonons. In the absence of any available
measured data in the literature, they could not be compared. Future experimental work will testify our calculated
results.
4. Conclusion
In conclusion, we have studied the electronic, elastic and thermal properties of RECd (RE=La, Ce and Pr) using
FP-LAPW method based on density functional theory. From band structure and density of states, we found that
these compounds exhibit metallic behaviour. In present study we found B/GH > 1.75 and C12–C44 > 0 for CeCd
and PrCd compounds, LaCd is found to be brittle in nature.
Acknowledgement
The authors are thankful to UGC (New Delhi) for the financial support for Major Research Project. SPS is
thankful to UGC (SAP).
References
[1] Wu, Y., Hu W., (2007). European Physical Journal B, 60, 75-81
[2] Divis, M., Kriplach J., (1995). Physica B, 205, 353-364
[3] Chen, L., Peng P., Han S.C., (2007). Rare Metal Materials and Engineering, 36, 2089
[4] Pasha, S.K., Sundareswari, M., Rajagopalan, M., (2004). Physica B, 348, 206-212
[5] Ricca, A., Bauschlicher, C.W., (1995). Chemical Physics, 200, 337
[6] Degtyareva, V.F., Porsch, F., khasanov, S.S., Shekhtmanand, V. Sh., Holzapfel, W.B., (1997). Journal
of Alloys and Compound,246, 248
[7] Fujii, H., Kitai, J., Uwatoko, Y., and Okamoto, T., (1985). Journal of magnetism and magnetic
material, 52, 428-430
[8] Sousa, J.B., Pinto. R.P., Braga, M.E., Aleonard, R., Morin, P. & Schmitt, D., (1983). Journal of Physics F:
Metal Physics, 13, 827
[9] Kadomatsu, H., Kurisu, M., Kitai, T., Okamoto, T., & Fujiwara, H., (1983). Physics Letters, 94A,
178-180
[10] Indelli, A., & Palenzona, A., (1965). Journal of the less common metal, 9, 1-6
[11] Perdew, J, P., Burke, K., Ernzerhof, M., (1996). Physical Review Letter, 77, 3865-3868
[12] Hohenberg, P., Kohn, W., (1964). Physical Review, 136, B864-B871
[13] Blaha, P., Schwarz, K., Madsen, G.K.H., Kvasnicka, D., & Luitz, J., Techn. Universit¨at Wien, Austria,
2001. ISBN 3-9501031-1-2
4. Advances in Physics Theories and Applications www.iiste.org
ISSN 2224-719X (Paper) ISSN 2225-0638 (Online)
Vol.19, 2013 - Selected from International Conference on Recent Trends in Applied Sciences with Engineering Applications
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[14] Birch, F., (1947). Physical Review, 71, 809-824
[16] Sun, Z., Li, S., Ahuja, R., Schneide, J. M., Calculated elastic properties of M2AlC (M =Ti, V, Cr, Nb
and Ta), (2004). Solid State Communication, 129, 589-592
[17] Hill, R., Proc. (1952). Physical Society London, A 65, 349-354
[18] Voigt, W., (1889). Annals of Physics, 38, 573-587
[19] Reuss, A., Angew, Z., (1929). Journal of Mathematical Physics, 9, 49-58
[21] Haines, J., Leger, J.M., & Bocquillon, G., (2001). Annual Review of Materials Science, Res. 31, 1-23
[22] Pugh, S.F., (1954). Philosophical Magazine, 4545, 823-843
[23] Pettifor, D.G., (1992). Journal of Materials Science and Technology, 8, 345–349
Table 1. Calculated lattice parameter a0 (A°), Bulk modulus B (GPa) its pressure derivative (Bʹ), magnetic
moment (µB) and elastic constants of RECd (RE= La, Ce and Pr) in B2 phase.
Solid work a0
(A°)
B
(GPa)
B' µB C11
(GPa)
C12
(GPa)
C44
(GPa)
LaCd GGA 3.932 47.54 4.48 - 72.71 33.37 37.01
LSDA 3.806 61.39 3.99 - 93.51 47.63 50.40
Expt. 3.905a
- - - - - -
CeCd GGA 3.8408 46.19 4.73 1.34 85.49 30.09 23.01
LSDA 3.7007 57.44 4.23 1.23 71.58 58.40 49.58
Expt. 3.865a
- - -
PrCd GGA 3.8502 42.09 3.88 2.74 57.5 40.8 28.6
LSDA 3.7079 56.22 3.74 2.63 63.28 53.98 9.79
Expt. 3.830a
- - - - - -
a
Ref [9] Expt. –Experimental.
Table 2. The calculated Young’s modulus (E), shear modulus (GH),anisotropy factor (A), Poisson’s ratio (σ),
B/GH ratio, Cauchy’s pressure (C12-C44), longitudinal (vl ), transverse (vt), average elastic wave velocity (vm) and
Debye temperature (θD) for LaCd, CeCd and PrCd using GGA approximation.
Solid
E
(GPa)
GH
(GPa)
A σ B/GH
C12-C44
(GPa)
ρx103
(kg/m3
)
vl
(m/s)
vt
(m/s)
vm
(m/s)
θD
(K)
LaCd 79.90 32.92 2.36 0.24
4
1.41 -13.11 29.20 1795.65 1106.55
2392
1219.9
2657
147.10
CeCd 63.54 24.78 0.83
3
0.28 1.95 7.08 29.59 1661.99 917.05 1021.2
112148
98.19
PrCd 46.65 17.50 3.42 0.33 2.64 12.20 29.44 1581.96 834.33 932.1 89.40
5. Advances in Physics Theories and Applications www.iiste.org
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Figure 1. (a)- (e) Density of state of RECd (RE=La, Ce and Pr) intermetallics.
Figure 2. (a) –(c) Band structure of RECd intermetallics.
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