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Al Basrah, Iraq

The University of Basrah is situated in the city of Basra, Iraq. For historic reasons the final -h is retained on Basrah in the name of the university.Founded in 1964 to meet the needs of southern Iraq, the University of Basrah was at first affiliated with the University of Baghdad, but in 1964 it became an independent body. Today the University consists of fourteen colleges located on three campuses around the city of Basra, with research facilities and student halls of residence .The University awards the degrees of BA, BSc, Higher Diploma, MA, MSc and PhD. Wikipedia.

Harfash A.J.,Durham University | Harfash A.J.,University of Basrah
International Journal of Engineering Science | Year: 2014

The purpose of this paper is to study the effect of a heat source on the solution to the equations for an incompressible heat conducting viscous fluid. The validity of both the linear instability and global nonlinear energy stability thresholds are tested using three dimensional simulation. Our results show that the linear threshold accurately predicts on the onset of instability in the basic steady state. However, the required time to arrive at the steady state increases significantly as the Rayleigh number tends to the linear threshold. © 2013 Elsevier Ltd. All rights reserved.

Badran H.A.,University of Basrah
Applied Physics B: Lasers and Optics | Year: 2015

A new dye compound containing azomethine groups has been synthesized and characterized by FT-IR, 13C NMR, and an UV–visible spectrometer. Measurements of the thermally induced optical nonlinearity of dichloro bis[2-(2-hydroxybenzylideneamino)-5-methylphenyl] telluride platinum(II) in a chloroform solvent were studied using a cw diode laser at 487 nm as the source of excitation, both in solution and as a poly methyl methacrylate solid film, respectively. The optical response was characterized by measuring the intensity-dependent refractive index n2 of the medium using the Z-scan technique. The sample showed negative and large nonlinear refractive index values of the order of 10−7 cm2/W and reverse saturable absorption with high values of the nonlinear absorption coefficient of the order of 10−3 cm/W. The nonlinear refractive index was found to vary with the concentration. These results indicate that the dye is a promising candidate for applications in the nonlinear optic field. Thermal lens spectrometry was applied to investigate the thermo-optical properties and the nonlinear refractive index. In this technique, a pump and a probe beam were aligned collinearly. A localized change in the refractive index of the sample due to the thermal heating produced a thermal lens, which was then detected by studying the focusing and defocusing of the pump and probe beam. © 2015, Springer-Verlag Berlin Heidelberg.

Badran H.A.,University of Basrah
Results in Physics | Year: 2014

In this work thermal lens spectrometry (TLS) is applied to investigate the thermo-optical properties of new organometallic compound containing azomethine group, Dichloro bis [2-(2-hydroxybenzylideneamino)-5-methylphenyl] telluride platinum(II), doped polyacrylamide gel using transistor-transistor logic (TTL) modulated cw 532. nm laser beam as an excitation beam modulated at 10. Hz frequency and probe beam wavelength 635. nm at 14. mW. The technique is applied to determine the thermal diffusivities, ds/. dT and the linear thermal expansion coefficient of the sample. All-optical switching effects with low background and high stability are demonstrated. © 2014 The Author.

Nasir Imtani A.,University of Basrah
Journal of Physics and Chemistry of Solids | Year: 2013

Equilibrium molecular dynamics based Einstein relation with an appropriate definition for integrated heat current (i.e., with modified energy moment) are combined to quantify the thermal conductivity of individual single-walled carbon nanotubes, armchair, zigzag and chiral tubes. The thermal conductivity has been investigated as a function of three parameters, tube radius, length and chirality at and near room temperature with Brenner potential model. Thermal conductivity is found to have unusually high value and varies with radius, length and chirality of tubes. Also the thermal conductivity at temperature range from 50 to 100 K is found to have a maximum value. For 12.1 nm tube length, the thermal conductivity has converging trend which its value dependents on the tube radius and chirality. Tubes with large radius have lower values of thermal conductivity. Furthermore, the results show that armchair tubes have large values of the thermal conductivity comparing with zigzag and chiral tubes. It seems possible to uncover carbon nanotubes thermal properties based on measurements having heat dependence by adding another methods for calculations. © 2013 Elsevier Ltd.

Chamkha A.J.,Public Authority for Applied Education and Training | Ismael M.A.,University of Basrah
Numerical Heat Transfer; Part A: Applications | Year: 2013

The conjugate natural convection-conduction heat transfer in a square domain composed of a cavity heated by a triangular solid wall is studied under steady state condition. The vertical and horizontal walls of the triangular solid are kept isothermal and at the same hot temperature Th. The other boundaries surrounding the porous cavity are kept adiabatic except the right vertical wall, where it is kept isothermally at the lower temperature Tc. Equations governing the heat transfer in the triangular wall and heat and fluid flow, based on the Darcy model, in the fluid-saturated porous medium together with the derived relation of the interface temperature are solved numerically using the second order central differences finite difference scheme with the successive over relaxation (SOR) method. The investigated parameters are the Rayleigh number Ra (100-1000), solid to fluid saturated porous medium thermal conductivity ratio Kr (0.1-10), and the triangular wall thickness D (0.05-1). The results are presented in the conventional form; contours of streamlines and isotherms and the local and average Nusselt numbers. An uncommon behavior of the heat transfer in the porous medium with the triangular wall thickness D is observed and accounted. © 2013 Copyright Taylor and Francis Group, LLC.

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