An experimental and numerical study has been carried out to investigate the forced convection heat transfer by clean or dusty air in a two dimensional annulus enclosure filled with porous media (glass beads) between two vertical concentric cylinders. The outer cylinder is of (82 mm) outside diameters and the inner cylinder of (27 mm) outside diameter. Under steady state condition; the inner cylinder surface is maintained at a high temperature by applying a uniform heat flux and the outer cylinder surface at an ambient temperature. The investigation covered values of input power of (6.3, 4.884, 4.04 and 3.26 W), Reynolds number values of (300, 700, 1000, 1500, and 2000) and dust ratio values (density number N) of (2, 4, 6 and 8). A computer program in MATLAB has been built to carry out the numerical solution by writing the governing equation in finite difference method. The local Nusselt number, the average Nusselt number, the contours of temperature field and velocity field were presented to show the flow and heat transfer characteristics. The results show that when clean air flow, the wall temperature gradually increases along the cylinder length in the direction of flow and decrease as Reynolds number increase while it increases with input power. For dusty air flow results show that the wall
temperature gradually increases along the axial direction and increase with Reynolds number and with input power, and the maximum reduction in heat transfer will be 30 % for N=8 at Re=2000. Comparison was made between the present experimental and numerical results and it gives good agreement. The experimental and numerical Nusselt number follows the same behavior with a mean
deviation of 12%.
The study of the dynamic behavior of packed distillation column was studied by frequency response analysis using Matlab program. A packed distillation column (80 mm diameter) (2000 mm height) filled with glass packing (Raschig Rings 10mm), packing height (1500 mm) has been modified for separation of methanol-water mixture (60 vol%). The column dynamic behavior was studied experimentally under different step changes in, feed rate (±30%), reflux rate (±22%), and reboiler heat duty (±150%), the top and bottom concentration of methanol were measured. A frequency response analysis for the above step response was carried out using Bode diagram, the log modulus and the phase angle were used to analyze the process model. A Matlab progra
... Show MoreParonomasia is a recognized rhetorical device by which poets could play with words that are similar or identical in form but different in meaning. The present study aims to identify paronomasia in Arabic and English. To achieve the aim of the study, a corpus of selected verses chosen from two famous figures in Arabic and English literatures and analyzed thoroughly. The analysis of data under investigation reveals that paronomasia is a crucial aid used by poets to portrait the real world as imaginative. It further shows that the concept of paronomasia in English is not the same as in Arabic. In English, there are echoes of the Arabic jinās, i.e., there are counterpart usages of similar devices, yet English rhetoricians have not defined or c
... Show MoreSuggestive ambiguity is a strategy of defense and maneuvering as it provides the speaker both protection and function. To put it differently, it helps the speaker to say whatever he likes and at the same time gives his opponents and friends the interpretation they desire. This is possible due to the flexibility of the linguistic expressions that the speaker uses. To be more clear, the context of situation, peoples' background and world knowledge interact with the significance of the linguistic expressions reaching an allusive situation where two interpretations, positive and negative, are available to the addressees. Such situation enables the addressers to implicate different ideas or messages, accusations, inciting violence, etc. The pres
... Show MoreIn this paper, we study the peristaltic transport of incompressible Bingham plastic fluid in a curved channel. The formulation of the problem is presented through, the regular perturbation technique for small values of is used to find the final expression of stream function. The numerical solution of pressure rise per wave length is obtained through numerical integration because its analytical solution is impossible. Also the trapping phenomenon is analyzed. The effect of the variation of the physical parameters of the problem are discussed and illustrated graphically.
Back ground: The innervations of the pineal
gland from the superior cervical ganglion have
shown some form of a chromatolysis reaction.
Objective:
1-Tracing the innervations of the pineal gland by
removing the target tissue (the pineal gland in
this study) i.e. (pinealoctomy) and removal of the
superior cervical ganglion i.e. (ganglionectomy).
2- The localization and total number of the
neurons which project into the rat pineal gland
3-The effect of pinealoctomy on the SCG after a
different time interval.
Methods: Twenty five albino rats were used in
this study, Pinealoctomy was done, then after a
different time interval ganglionectomy was done,
in order to study the Chromatolysis in their cel
Objectives: This study aims to broaden our knowledge of the role of eDNA in bacterial biofilms and antibiotic-resistance gene transfer among isolates. Methods: Staphylococcus aureus, E. coli, and Pseudomonas aeruginosa were isolated from different non-repeated 170 specimens. The bacterial isolates were identified using morphological and molecular methods. Different concentrations of genomic DNA were tested for their potential role in biofilms formed by study isolates employing microtiter plate assay. Ciprofloxacin resistance was identified by detecting a mutation in gyrA and parC. Results: The biofilm intensity significantly decreased (P < 0.05) concerning S. aureus isolates and insignificantly (P > 0.05) concernin
... Show MoreThe general crisis of research methods in the social sciences
Research methodology: philosophy and techniques, founded by philosophers and applied by scientists, and no accurate application of techniques except with a deep understanding of philosophy, as a prerequisite. This fact is almost completely absent from the Iraqi and Arab academic mentality. This constituted one of the dimensions of the double crisis - theoretical and applied - of research methods in the social sciences. As first, there is no philosophy of science, neither as an independent material nor as an introductory subject, but not even an oral confirmation. Secondly, the advancement of quantitative research methods are presented without a background philosophy, as sol
Serum levels of iron,copper,ceruloplasmin and transferrine were estimated in three groups of patients with ?- thalassemia: 24 patients have splenectomy thalassemia major, 29 patients have non splenectomy thalassemia major and 19 patients have thalassemia intermedia , data were compared to normal and pathological controls (anemia and minor). There were significant increase in trace element levels in all studied groups of pateints as compared to normal and pathological controls. Also there were a significant increase in ceruloplasmin levels,While the result revealed that there were a significant decrease in transferrine levels in all groups of patients studied as compared to normal and pathological controls. The result also indicate that the
... Show MoreThe objective review is to inspect the involvement of Interleukin-6 (IL-6) in rheumatoid arthritis (RA) and to highlight the role of IL-6 and its variants in the pathogenesis of RA and response to anti-IL-6 agents. Several genetic and environmental risk factors and infectious agents contributed to the development of RA. Interleukin-6 is engaged in self-targeted immunity by modifying the equilibrium between T regulatory (T-reg) and T helper-17 (Th-17) cells. The evidences reported that IL-6 parti
Theoretical trends have appeared Which posed the concept of biological structures in contemporary architecture concept, Spread through the emergence of architectural production that reflect and indicate the nature of the construction structures based on the ideas and principles of biological structures in biological science: Despite the emergence of many architectural proposals that tried to explain the concept in the field of architecture, but it is not dealt with in depth and not given a comprehensive definition: So there was need to search for the concept and its beginning in the biological field as a general framework down to the field of architecture for the purpose of reducing the limits of their search framework T
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