Vol. 5 & Issue 1 ; Section C : Physical Sciences

Date : Nov.2014 to Jan.2015

 

A theoretical evaluation of in plane Spectral Weight, Optical Conductivity and Screened Plasma frequency of Optimal and Under doped high-TC Superconductor as a function of Photon energy in the Superconducting State

Manjeet Kumar Singh and L. K. Mishra

  • Abstract

    In this paper, we have theoretically evaluated in-plane spectral weight, optical conductivity σ (ω), dielectric constant ε (ω), screened plasma frequency of optimal doped and under doped high TC superconductor Bi2Sr2CaCu2O8-δ. The evaluation is performed taking theoretical formalism of H. J. A. Molegraafetal. Science, 295 (2002). We observed that the onset of superconductivity is accompanied by a transfer of spectral weight from spectral region above 10,000cm-1 to the inter band optical spectrum. This behavior contradicts the traditional models of superconductivity. It is strong indication that superconductivity in cuprates is unconventional. Our other theoretical results like σ (ω) and ε (ω) are in good agreement with other theoretical workers.

A theoretical evaluation of surface Plasmon dispersion coefficient α for various simple metal surfaces

Md. Naiyar Perwez, A. Anzer and L. K. Mishra

  • Abstract

    In this paper, we have evaluated long wavelength surface Plasmon dispersion coefficients α (A0) for various simple metal surfaces using various models HD, SRM, IBM, RPA, and ALDA. It was observed that the surface Plasmon dispersion coefficient evaluated using RPA and ALDA models are negative as per experimental observations but the magnitudes are large. On the other hand α (A0) evaluated from HD and SRM models are positive but the magnitudes match with the experimental data.

Conformal structures in a Manifold

Sandeepa Bhandari and K. C. Petwal

  • Abstract

    The theory of conformal manifolds arose in studying those properties of Riemannian and Pueudo-Reimainnian manifolds that remain invariant under conformal transformations of metric. Cartan3,4 introduced and studied a manifold M with conformal connections considered by many authors. In this paper, we study conformal structures of a manifold of arbitrary dimension and also we study the theory of curves and a submanifold of different dimensions in a space with a conformal connection was developed.

Fekete-Szegö Inequality for Certain Subclasses of Analytic Functions

Gurmeet Singh and Ghanshyam Singh Rathore

  • Abstract

    We introduce some classes of analytic functions, its subclasses and obtain sharp upper bounds of the functional  for the analytic function  belonging to these classes and subclasses.𝑎22|

     

A Theoretical Analysis of Electronic Specific Heat, Entropy,Magnetic Susceptibility as a Function of Temperature ofNon-Fermi D-And F-Electron Metals Using EmpiricalFormula

Ram Pyare Prasad, G. P. Gadkar and L. K. Mishra

  • Abstract

    In this paper, we have theoretically analyzed the data of electronic specificheat, electronic entropy and magnetic susceptibility results of non-Fermi-liquid (d- and felectron) compounds. We have used an empirical formulas based on multichannel Kondo model and disorder-induced models. Our theoretically analyzed results are in good agreement with the experimental data and also with others theoretical workers. 

The Effect of Rotation on the Onset of Double Diffusive Convection in a Saturated Anisotropic Porous Layer with Internal Heat Source

S.N.Gaikwadand Anuradha V Javaji

  • Abstract

    In the present study, the effect of rotation on the onset of convection in a saturated anisotropic porous layer with internal heat source is investigated analytically using linear and nonlinear theories. The linear theory is based on the normal mode technique and the nonlinear theory on the truncated Fourier series. The Brinkman model that includes the Coriolis term is employed for the momentum equation. The onset criterion for stationary, oscillatory and finite amplitude convection is derived analytically. The effect of internal Rayleigh number, Taylor number, Darcy-Prandtl number, Thermal and Mechanical anisotropic parameters, Lewis number, normalized porosity and solute Rayleigh number on stability of a system is shown graphically. The transient behavior of the Nusselt and Sherwood numbers is obtained by solving the finite amplitude equations using the Runge-Kutta method.

A theoretical Study of Surface Plasmon-Polaritons at metal surface and evaluation of dispersion relation of SPPs at a metal/air boundary

Naiyar Perwez, Afaque Anzer & L. K. Mishra

  • Abstract

    Using the theoretical formalism of Maier and Atwater (J. Appl. Phys, 2005) and Asanka Pannipitiya (Optic Express, 2010), we have evaluated dispersion relation of SPPs propagating at Ag/air, Ag/glass and Ag/Si interface and MDM (Metal-dielectric- Metal) waveguide. This study gives the possibility of localization of electromagnetic energy in one, two and three dimensions. This can also be applied in sensing and wave guiding for fundamental photonic devices. Our obtained results of dispersion relation of SPPs both at interface and MDM waveguide are in satisfactorily agreement with the experimental data and also with other theoretical workers.

On Stability of Frames in Hilbert Spaces

S.K. Kaushik, Ghanshyam Singh and Virender

  • Abstract

    Frames in Hilbert spaces have been perturbed by an arbitrary sequence of the space and observed through examples that the perturbed sequence may not be a frame for the space. Sufficient conditions for the stability of frames under perturbation have been given. Also, it has been observed that finite sum of frames in Hilbert space may not be a frame. A necessary and sufficient condition for the finite sum of frames to be a frame has been given. Finally, sufficient conditions for the stability of finite sum of frames have been given.

Study of acoustic and thermodynamic parameters for binary mixture containing cyclohexane and the substituted benzenes at different temperatures

Manoj Kumar Praharaj and Sarmistha Mishra

  • Abstract

    Ultrasonic velocity, density and viscosity have been measured for binary mixtures of Cyclohexane and the substituted benzene at different temperatures 288K, 298K, 308K, 318K, the frequency being fixed at 6 MHz. These experimental data have been used to study the different thermodynamic parameters and their excess values.

On Higher Order Recurrent Normal Projective Finsler Space

N. L. Yadav, S. B. Misra, K. Srivastava, R. B. Srivastava

  • Abstract

    In the present communication we have derived the conditions under which in a U-recurrent Finsler space the tensor ()iirjkhrjkhGG− behaves like a 1-recurrent tensor field along with the necessary and sufficient condition under which in a U-recurrent Finsler space the tensor field rrjkhG is 1-recurrent. In this continuation we have derived the conditions under which in all recurrent Finsler space the directional derivative of ijkhG is proportional to ijkhG and in the sequel have also established that there does not exist any concurrent or concircular vector field in a U-recurrent Finsler space.

Structural and Morphological Properties of NiO Thin Films by RF-Sputtering

Dr.Mohammed Abdul-Nabi, Dr.kassem aziz1 and ZenabTarq

  • Abstract

    Nickel oxide thin films have been prepared with different thicknesses (100,150 and 200nm) on glass and Si substrate using RF-magnetron sputtering at ambient and 100°C substrate temperatures. The X-ray diffraction study reveals that the films are polycrystalline in nature with cubic structure. The effect of the thicknesses on structural and morphological has been studied using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). In the present work, an approximation method was made to determine both the crystallite size and number of crystallites from XRD profile of NiO films. It was found that all samples shows polycrystalline consisting of nickel oxide cubic phase, comprising a strong reflection along (220) plane and a weak reflection along (111) plane. Comparison of crystallite size and number of crystallites were investigated using different definitions of line broadening. The approximation method was foun

Commercial Applications of Superconductors in Different areas of Human Life’s

Sudhakar Singh

  • Abstract

    In the early years of the twentieth century, the Dutch physicist H. Kamerlingh Onnes and his team of researchers began to study the properties of matter at very low temperatures, between -271° C and -259° C. In1911they observed that the electrical resistance of mercury tends to zero at a temperature of 4.2K or -2690C .They had just discovered superconductivity, a contribution for which they were awarded the 1913 Nobel Prize for Physics. Some technological innovations benefiting from the discovery of superconductivity include sensitive magnetometers based on SQUIDs, digital circuits (e.g. based on the RSFQ logic), Magnetic Resonance Imaging, Beam-steering magnets in particle accelerators, electric power transmission cables, and microwave filters (e.g., for mobile phone base stations). Promising future industrial and commercial applications include transformers, power storage, propulsion systems for vehicles such as ships and spacecraft,

A Theoretical evaluation of energy gap of molecules with different mass ratio in Fermi-Bose mixtures near broad interspecies Fehbach resonances

Sunil Kumar, Balaram Singh and L. K. Mishra

  • Abstract

    In this paper, we have theoretically studied Fermi-Bose mixtures near broad interspecies resonances. Using Variational method, we have evaluated energy of the molecule, WB as a function of scattering length [KFabf]-1 for different mass ratio, critical scattering length [KFa(1)]-1 as a function of (mB/mF), pair-breaking energy Δ in the unit of (εFR) and pair chemical potential μ(εFR) as a function of scattering length [KFabf]-1 for 40K- 87Rb.Our evaluated theoretical results are in good agreement with other theoretical workers.

The Optical Properties of (PVC-PS) Blends

Bushra.A.Hasan and Ikhlas H. Shallal

  • Abstract

    Influence of blend ratio on the optical constants (refractive index (n), extinction coefficient (k), and real & imaginary parts of dielectric constants (ε1) & (ε2)) of Polyvinylchloride-Polystyrene (PVC-PS) blends using the transmittance and reflectance spectra have been discussed. The results showed that the optical constant increase when the addition of PS to PVC lead to increase the density of blend sample while they decrease when the addition of PS lead to decrease the density of blend sample .k declared similar behavior of n with blends ratio . The exciton states which declare behavior simulated that of optical energy gap Eg show an opposite sequence to that of optical constants. Minimum energy gap obtained was 2.4 eV at blend ratio 25/75PVC/PS.

A theoretical estimation of effective penetration depth and surface resistance and surface reactance in low TC and high TC superconductor

Khushboo Kumari, Archana kumari Sinha and L. K. Mishra

  • Abstract

    In this paper, we have theoretically studied the microwave electrodynamics of low TC and high TC systems with coexisting superconductivity and magnetism. We observed that in the case of Nb/CuMn (superconducting/spin glass) bilayers and on GdBa2Cu3O7-δ(TC=92.5K)(GBCO) thin film there is a coexistence of superconductivity and long range ordered antiferromagnetism below TN=2.5K. We have evaluated microwave surface impedance at three microwave frequencies on GBCO. The evaluation has been performed using the theoretical formalism of L. V. Mercalde etal.(1999). Our theoretical results show an unusal low temperature behavior of both resistance and reactance on GBCO. This is due to change in magnetic permeability. Our theoretical results are in good agreement with the experimental data and also with other theoretical workers.

A Theoretical Study Of Thermo Physical Properties of Carbon Nanotubes and an Evaluation of Temperature Dependent Its Parameters

Kirpal Singh, Bharat Singh and L. K. Mishra

  • Abstract

    In this paper, we have theoretically evaluated the temperature dependent specific heat and thermal conductivity of carbon nanotube. From our theoretical results, it appears that at high temperatures the specific heat of individual nanotube is similar to that of 2D graphene. The phonons contribution appears to dominate at low temperature and linear T dependence is obtained for SWNTs of diameter <2nm. The temperature dependent thermal conductivity is also dominated by phonons. Our results also show the 1D quantization of phonon band structure. Our theoretical results indicate that nanotube composite materials may be useful for thermal management applications.

A theoretical analysis of surface resistance and surface reactance as a function of temperature for low TC superconductor

Khushboo Kumari, Archana kumari Sinha and L. K. Mishra

  • Abstract

    In this paper, we have theoretically analyzed the high frequency magneto electrodynamics behavior of low Tc superconductor DyNi2B2C in the superconducting and antiferromagnetic state over wide range of temperature T and magnetic field H. We have analyzed the T dependence of surface impedance ZS and penetration depth λ. Our analyzed results show that both RS and XS increases with T up to 12K and then it saturates. Both RS and XS differ from each other even in the AFM state below TN. The theoretical evaluation is performed with the help of two theories M. L. Kulic etal (Physica C (1995) and T. Ishiguo etal.( J. Supercond.(1994) Our theoretically analyzed results are in good agreement with the experimental data.

A theoretical Study of locaized Plasmon resonances in metal Nanoparticles

Mukesh kumar Gaurav, P. K. Verma & L. K. Mishra

  • Abstract

    Using the theoretical formalism of Maier and Atwater (J. Appl. Phys, 2005),we have theoretically studied the localized Plasmon resonances in metal nanoparticles.We have evaluated the absorbance (ab. Units) as a function of energy for thin gold film,30nm Au nanoparticle. We have also presented the evaluated results of light scattering spectra as a function of photon energy (eV) of Au nanocrystal 100nm. This study gives the possibility of localization of electromagnetic energy in one, two and threedimensions. This can also be applied in sensing and wave guiding for fundamental photonic devices. Our obtained results of dispersion relation of SPPs both at interface and MDM waveguide are in satisfactorily agreement with the experimental data and also with other theoretical workers.

A Theoretical Study of Dispersion Relation in Plasmonic MDM (Metal-Air-Metal) Waveguides

Mukesh Kumar Gaurav, P. K. Verma and L. K. Mishra

  • Abstract

    In this paper, using the theoretical formalism of Asanka Pannipitiya etal (Optic Express, 2010), we have studied the dispersion relation in plasmonic MDM (Metal-Air-Metal) waveguide. We have evaluated the real and imaginary part of the dielectric permittivity of Ag-air-Ag waveguide using Drude- Lorentz model. We have also evaluated real part of effective refractive index and propagation length of SPPs of different thickness h of air layer of MDM waveguide. Our theoretical results show that the refractive index decreases with thickness h. In another calculation, we have evaluated transmittance as a function of wavelength and stub length d for MDM waveguide with single stub of finite thickness. Our evaluated results indicate that transmittance first increases and then decreases sharply as a function of wavelength λ. We have used three models in this evaluation. Our evaluated results are in good agreement with other theoretical workers and also with

Transmission and reflection behaviour of x-band microwaves passing through wheat seeds

D. V. Ahire and P. R. Chaudhari

  • Abstract

    This study reports the experimental results on the attenuation parameters of microwave signal having 9.0 GHz frequency passing through wheat seed/grain samples. Wheat seeds are filled into a rectangular shaped sample holder having various thicknesses ranging from 2.5 to 12 cm. The sample holder is fabricated from uniform and thin plain perspex sheet and it is then arranged centrally between the transmitting and receiving horn antenna. Measurements of Insertion Loss (IL) of microwaves are made by using free space method. These measured values of IL are then used to estimate the transmission coefficient (T), reflection coefficient (Γ), Return Loss (RL) and Voltage Standing Wave Ratio (VSWR) for these wheat seed samples by using appropriate relations. Moistures of these wheat seed samples are then varied from its edible value of gravimetric Moisture Content (MC, %) to oven dry value (0 % MC). The IL, Γ and VSWR are found to increase with increas

An Evaluation of Critical Temperature (Tc) for Bose-Einstein Condensation (BEC) of the Atom-Molecule Mixture at the Total Fixed Atomic Density

Shiv Narayan Choudhary, Bisha Mohan Kumar and L. K. Mishra

  • Abstract

    Using theoretical formalism of R. A. Duine and H. T. C. Stoof (Physics Reports, 2004) we have evaluated the critical temperature TC for Bose-Einstein condensation (BEC) for the atom-molecule mixture at the fixed total density. The evaluation has been performed for positive and negative detuning. For positive detuning, we obtained TBEC =T0 and for negative detuning, we have TBEC =(2-5/3T0) where T0 is initial temperature. Our theoretically evaluated results are in good agreement with the experimental data and also with other theoretical workers.

Effect of Physical and Chemical Mutagens on Seed Germination and Seedling growth of Garden Bean

S. Monica and N. Seetharaman

  • Abstract

    The present investigation was carried out to find the LD₅₀ value, seed germination and seedling growth induced by Gamma rays and EMS in Lablab purpureus (L.) Sweet var. typicus cv. CO (Gb) 14. The study was performed by exposing the seeds with various doses of Gamma rays (5, 10, 15, 20, 25, 30, 35, 40, 45 and 50kR) and different concentrations of EMS (5, 10, 15, 20, 25, 30, 35, 40, 45 and 50mM) along with control. The effect of mutagens on germination was observed on 7th day and seedling characters like, shoot length and root length were recorded on 7th day and 15th day after sowing. The germination percentage and seedling growth decreased with increase in doses/concentrations of the mutagens. Mean performance of different quantitative traits were better in control when compared with the treated plants. The lethal dose 50 (LD₅₀) value was found at 25kR of gamma rays and 30mM of EMS.

Binding Energy Evaluation of a Quantum nano dot as a function of dot radius at different concentrations

Bhavibhuti Narayan Mishra and L. K. Mishra

  • Abstract

    We have evaluated the binding energy of spherical GaAs/Ga1-xInSb quantum dot as a function of dot radius at different composition x using the theoretical formalism of T. Prem Kumar et. al. (2011). We observed that binding energy decreases with increase of dot radius with fixed concentration x. we also observed that if dot radius is kept fixed then binding energy increases with composition x. These observations are consentient with observations of other theoretical workers.

A theoretical study of non-Fermi-liquid behavior of U-based f-electron Compounds Sc1-xUxPd3, URu2-xRexSi2 and Ce (Ru1-xFex)2Ge2

Ram Pyare Prasad, G. P. Gadkar and L. K. Mishra

  • Abstract

    Using the theoretical formalism of M.B. Maple etal (Physica B 2006) and W. Montfrooij etal (Phys. Rev B 2006), we have theoretically analyzed the non-Fermi-liquid compounds Sc1-xUxPd3, URu2-xRexSi2 and Ce(Ru1-xFex)2 Ge2. Using an empirical formulas and varying the critical exponent, we have evaluated its various parameters such as specific heat, magnetic susceptibility etc. of the non-Fermi –liquid compounds. Our theoretically evaluated results are in satisfactorily agreement with the experimental data and also with other theoretical workers.

A theoretical study of Bose-Einstein condensation(BEC) for trapped atomic polaritons in a biconical waveguide cavity and an evaluation of polariton- photon fraction and normalized LB polariton mass as a function of z for different trapping power parameter

Shapla Kumari, Narendra Singh & Lalit Kumar Mishra

  • Abstract

    Using, the theoretical formalism of I. Yu. Chestnov etal. (2012), we have studied BEC for trapped atomic polaritons in a biconical waveguide cavity. We have theoretically evaluated polariton-photon fraction and normalized LB-polariton mass as a function of characteristic length Z for different trapping power parameter ν. It was observed that for value Z<Z1/2, LB polariton behaves as particle (photon like) with constant mass. Polaritons are mixed state of photons and excitations of two-level atomic system. Our theoretically evaluated results are in good agreement with other theoretical workers.

Study the Electron Drift Velocity in Carbon Dioxide Gas Obtained From Boltzmann Equation Analysis

Dhuha Sadi Abdul Majeed

  • Abstract

    The electron drift velocity behavior in carbon dioxide pure gas is studied for E/N from 0.7 Td to 4000 Td (1 Td = 10-17V.cm2) this is gas is usual used in many processes and application, of the most important uses in enhancing the production of oil and electricity production to reduce the risk of a rising proportion of greenhouse gases in the atmosphere. The results obtained by using a simple two term solution for Boltzmann equation, for gas carbon dioxide. We found that he possessed a high drift velocity and which may be useful when mixed with other gases and also found generally the values of vd increase with increasing E/N .We found good agreement between calculated and measured values for electron drift velocity in pureCO2. These results are useful for determining the electron drift velocity which is an important transport parameter, which will be responsible for the movement of electrons in gases and may b

Preparation Polylactic acid by Polycondensation method

Nadia Abbas Ali

  • Abstract

    Polylactaic acid was synthesized by direct condensation polymerization of lactic acid. Polymerisation was carried out with tin chloride as a catalyst and methylene chloride as a solvent .The obtained PLA was characterized by XRD, and FTIR. The thermal properties i.e. Tg , Tc, Tm and Xc were obtained of powder PLA .

Hydrodynamic study of multi-phase semi-fluidization with binary mixtures of activated alumina beads

D. K. Samal, S. Mishra, Y. K. Mohanty, G. K. Roy

  • Abstract

    Semi-fluidization (sf) bed characteristics with activated alumina beads (AAB) are having importance when used as catalytic two and three phase processes and operations. The hydrodynamic studies have been made using binary mixtures of activated alumina beads (-3.5+4 and -4+5 BSS) as bed materials in 0.05 m internal diameter cylindrical columns with water as the fluidizing medium (two-phase semi-fluidization) and water in continuous phase with air in bubbling phase( three-phase semi-fluidization). Experimental parameters studied for the above cases include initial static bed height, average particle diameter, superficial liquid velocity, bed expansion ratio and in addition, superficial gas velocity (in case of three phase sf). Empirical and semi-empirical models have been developed with the help of dimensional and statistical analyses. The calculated values from the predicted models have been compared with the experimental ones and fairly good agreement ha