A numerical investigation has been performed to study the effect of eccentricity on unsteady state, laminar aiding mixed convection in a horizontal concentric and eccentric cylindrical annulus. The outer cylinder was kept at a constant temperature
while the inner cylinder was heated with constant heat flux. The study involved numerical solution of transient momentum (Navier-Stokes) and energy equation using finite difference method (FDM), where the body fitted coordinate system (BFC) was
used to generate the grid mesh for computational plane. The governing equations were transformed to the vorticity-stream function formula as for momentum equations and to the temperature and stream function for energy equation.
A computer program (Fortran 90) was built to calculate the bulk Nusselt number (Nub) after reaching steady state condition for fluid Prandtl number fixed at 0.7 (air) with radius ratio ( =2.6), Rayleigh number (Ra=200), Reynolds number (Re=50) for both concentric and eccentric cylindrical annulus with different eccentricity ratios (ε=0, 0.25, 0.50, 0.75) and angular positions (φo=0o
, 45o , 90o , 135o , 180o ).
The results show a reasonable representation to the relation between Nusselt number and (ε, φo). Generally, Nub decreased with the increase in (ε and φo). Also, results show that the best thermal performance for the inner cylinder was at the angular
position (φo=0o ) for eccentricity ratio (ε=0.25), while the maximum reduction in the rate of heat transfer for the inner cylinder was at the angular position (φo=180o) for eccentricity ratio (ε=0.75).
Comparison of the result with the previous work shows a good agreement.
The current investigation conducted to examine the anatomical aspects of the Arum colocasia L. cultured in Iraq. The study included the anatomical characteristics of the different plant parts, including the root, stem and leaf, the results of the study on the vegetative parts were shown the important anatomical characteristics in terms of the form of the sections reviewed and vertical in them, and the study of their tissues, as well as the stomata complexities and the thickness of the epidermis, vascular bundles, pith, additionally the dimensions of mesophyll and in blade of the leaf. The research was conducted as it is one of the monocotyledon plants and because of the lack of anatomical studies on it, therefore it was studied to know the
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המחקר הזה הוא ניסיון לשפוך אור על נושא מרכזי וחשוב בחייהם של היהודים, "הממד הדתי" אצל היהודים, מחקרי הנקרא "הממד הדתי בסיפור העברי המודרני" גם מתייחס להשפעת התרבות הדתית של המספר והחוג המשפחתי שחי בו, ואיך שיקף המספר את כל הדברים האלה ביצירותיו הסיפורית .
המספר בוחר במילים ובמונחים בעלי משמעויות דתיות או מביא את הסיפור הזה אשר קרוב אל נושא הסיפור ההולך באותה מגמה .גם כן השפעת התיאולג
... Show MoreThis study aims at re-transmit the spirit of the national democratic project of Iraq post of the chaos left by the Daesh terrorist group stage(The Islamic State of Iraq and Syria, ISIS) , Which controlled large parts of Iraq, and had an adverse effect on the political scene in Iraq, inspired everyone that there are deficiencies in the political, economic, religious and ethnic structure of the Iraqi people in non-response to democratic thought.The researcher relied on the hypothesis that " the requirements of building a democratic project are based on the need to provide the requirements ranging from two interrelated aspects, like the institutional aspect and the aspect that related to the general and necessary requirements for the e
... Show MorePvcABCD are cluster of genes found in Pseudomonas aeruginosa. The research was designed to examine the relationship between the pvc genes expression and cupB gene, which plays a crucial role in the development of biofilm, and rhlR, which regulates the expression of biofilm-related genes, and to investigate whether the pvc genes form one or two operons. The aims were achieved by employing qRT-PCR technique to measure the gene expression of genes of interest. It was found that out of 25 clinical isolates, 21 isolates were qualified as P.aeruginosa. Amongst, 18(85.7%) were evaluated as biofilm producers, 10 (47.6%), 5 (23.8%), and 3 (14.2%) were evaluated as strong, moderate and weak producers respectively, while, 3 (14.2%) were considered
... Show MoreVisceral leishmaniasis (VL) or kala-azar is one of the worlds most neglected tropical diseases in mortality and fourth in morbidity, rK39 dipstick was used to diagnose the suspected infected patients as cheapest simple technique which can differentiate recent from chronic infection, for disease out-coming, naïve T-lymphocyte cells should be differentiated into pathogen-specific immunity responses, such as T-helper 1(Th-1) or (Th-2). HLA-G is a special protein defined as nonclassical HLA class I molecule can suppress the immune system through prevention of T-cell function by foul all T-cell mechanisms. So, this study aimed to detect and evaluate the level of sHLA-G in the sera of patients infected with VL. The results showed that there was
... Show MoreBackground: urethrocutaneous fistula after hypospadias surgery repair is the most common complication and remains a frustrating problem for surgeon and the patient. The problem is exacerbated because the urethrocutaneous fistula may recur which adds more demands surgery. Objectives: The purpose of this study is to evaluate of the use of oral mucosal graft for management of recurrent urethrocutaneous fistula after hypospadias repair. Patients and Methods: twelfth patients with age ranging from 4 year to 15 years were presented with history of recurrent fistula. Most of fistula were located in proximal penile and penoscrotal region (58.3%) . those patients were repaired by using oral mucosal graft with mean postoperative follow up period up t
... Show MoreThe aim of the present work is to develop a new class of natural fillers based polymer composites with sawdust (S.D) which used two particle sizes (1.2 μm & 2.3 μm) and different weight percentage from sawdust (10%, 15%, and 20%). The mechanical properties studied include hardness (shore D) for all samples at normal conditions (N.C). The unsaturated polyester (UPE) and its composites samples were immersed in water for 30 days to find the effect of particle size of sawdust (S.D) on the weight gain (Mt %) by water for all the samples, also to find the effect of water on their hardness. The results show that the composite materials of sawdust (S.D) fillers which has particle size (1.2 μm) better than (2.3 μm) particle size bef
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