IOSR-JAP   Volume-10 ~ Issue-2 ~ March-April 2018

ABSTRACT: Thin films (TFs) having composition ofundoped and Al-doped ZnO were deposited onto synthesized glass substrates using spray pyrolysis technique with doping concentrations of 0, 10, 15 and 20% at annealing temperature of 200oC - 400oC. The effects of the doping concentrations on the optical properties of the as-deposited films were investigated by exploiting UV-Visible spectrophotometer and Bruker profilometer to evaluate quantify surface roughness and thicknessin the spectra range of 250nm to 1200nm. The obtained results show that metallic Zn films have a preferential (011) c-axis orientation instead of the common (002) predilection. The average transmittance of the undoped film is over 90%, while the doped films have less than 70% mean transmittancein the visible region and the observed optical band gap energy increases from 3.12eV to 3.24eVwith the increase of Al doping concentrations. The lowest resistivity of 248.13Ωcm and the highest conductivity of 403.0 x 10-5(Ωcm)-1 was obtained in the film with 20% doping concentrations.

Keywords: Spray pyrolysis technique, Band gap, Al doping, ZnO TFs, UV-Vis

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ABSTRACT:Decelerating Bianchi Type VI0Universe Modelwithtimedependent∧Termisinvestigated.To obtain the determinant solution of Einstein's field equation, we assume n A  B and  . Physical and geometrical properties are also discussed.

Keywords: Bianchi Type VI0, decelerating, Cosmology

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ABSTRACT: Recently, the great research attention on strontium doped lanthanum manganite (LSM), due to their significant report of transport and electrical properties. When La1-xSrxMnO3-δ (LSM) compound material synthesized in thin film form for solid oxide fuel cell (SOFC) cathode it helps to minimize its operating temperature. In the present study LSM thin films were synthesized by spray pyrolysis technique with the heat treated at 900 C O for 2 hours. These heat treated samples were used for characterization such as impedance measurement with frequency variation and temperature dependent measurement of dielectric constant. The variation of impedance with frequency indicates the presence of relaxation time and space charge polarization in the system.

Keywords: Spray Pyrolysis, impedance, dielectric constant Cathode, LSM, SOFC

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ABSTRACT: This theory is an attempt to describe the universal phenomena like space, time, matter and energy as an inter-relationship bound by a newly discovered force named as the universal force. The universal force is shown to be the force of gravitation, electricity, magnetism, strong nuclear and weak nuclear forces. I believe any other force, hitherto fore not discovered; also, can be explained in terms of this universal force. Liberal use of wave-particle duality, relativity, quantum concepts is made to achieve a harmonious and comprehensive synthesis of all the existing beliefs in physics into a new theory with some new concepts added here and there. While adding new concepts, enormous care has been taken to ensure that the existing beliefs are not contradicted. Moreover, the new concepts are proved to be correct theoretically by deriving the constants like G, σ , etc.,.

Keywords: Space, Time, Matter , Energy, Universal Force

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