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joe-1531
Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins
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Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh number and number of foam fins in the axial direction, on fluid flow and heat transfer characteristics, were examined. The current model was valid with the available published results and good agreement is noticed. Results showed that as the Rayleigh number increases the dominated of convection mode increases and average Nusselt increases. It was found that at Rayleigh of 106 Nusselt reached its higher value which is 4.6 for the case of adding seven axial metal foams. A comparison between adding foam fins and copper fins was established for a range of Rayleigh numbers between 104 and 106. It showed a good enhancement in Nusselt number and the greatest enhancement percentage was 45.9% at Rayleigh equal 106 for the case of using seven sections of foam fins.

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Publication Date
Fri May 01 2020
Journal Name
Journal Of Engineering
Chemical and Thermal Investigation on Stability of Tanuma Formation Using Different Additives with Drilling Fluids
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Wellbore stability is considered as one of the most challenges during drilling wells due to the
reactivity of shale with drilling fluids. During drilling wells in North Rumaila, Tanuma shale is
represented as one of the most abnormal formations. Sloughing, caving, and cementing problems
as a result of the drilling fluid interaction with the formation are considered as the most important
problem during drilling wells. In this study, an attempt to solve this problem was done, by
improving the shale stability by adding additives to the drilling fluid. Water-based mud (WBM)
and polymer mud were used with different additives. Three concentrations 0.5, 1, 5 and 10 wt. %
for five types of additives (CaCl2, NaCl, Na2S

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Publication Date
Sun Oct 01 2023
Journal Name
Baghdad Science Journal
The Necessary and Sufficient Optimality Conditions for a System of FOCPs with Caputo–Katugampola Derivatives
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The necessary optimality conditions with Lagrange multipliers  are studied and derived for a new class that includes the system of CaputoKatugampola fractional derivatives to the optimal control problems with considering the end time free. The formula for the integral by parts has been proven for the left CaputoKatugampola fractional derivative that contributes to the finding and deriving the necessary optimality conditions. Also, three special cases are obtained, including the study of the necessary optimality conditions when both the final time  and the final state  are fixed. According to convexity assumptions prove that necessary optimality conditions are sufficient optimality conditions.

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Publication Date
Sat Dec 21 2024
Journal Name
Gastroenterology
Evaluation of global DNA methylation, homocysteine and vitamin B12 levels among patients with celiac disease
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Celiac disease (CD) is an immune-mediated disorder caused by gluten in genetically susceptible individuals characterized by chronic inflammation that essentially affects the small intestine. Objective: this study was designed to measure the potential role of some serological biomarkers including vitamin B12 and homocysteine (HCY) in the progression of CD as well as their relations to global DNA methylation (5mC). Materials and methods. Forty CD patients were enrolled in the study with an average age of (36.60 ± 2.03) years (range between 15 and 60). The diagnosis of the disease was confirmed by serological examinations and intestinal endoscopy in Gastroenterology and Liver Teaching Hospital in the Medical City Hospital in Baghdad

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Publication Date
Sat Jan 01 2022
Journal Name
International Journal Of Low-carbon Technologies
Performance evaluation of the photovoltaic thermal system with a fin array and surface zigzag layout
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Abstract<p>Solar photovoltaic (PV) has many environmental benefits and it is considered to be a practical alternative to traditional energy generation. The electrical conversion efficiency of such systems is inherently limited due to the relatively high thermal resistance of the PV components. An approach for intensifying electrical and thermal production of air-type photovoltaic thermal (PVT) systems via applying a combination of fins and surface zigzags was proposed in this paper. This research study aims to apply three performance enhancers: case B, including internal fins; case C, back surface zigzags; and case D, combinations of fins and surface zigzags; whereas the baseline smooth duct rep</p> ... Show More
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Publication Date
Wed Aug 05 2020
Journal Name
Advances In Civil Engineering
Strength compensation of deep beams with large web openings using carbon fiber–reinforced polymer sheets
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This article presents the results of an experimental investigation of using carbon fiber–reinforced polymer sheets to enhance the behavior of reinforced concrete deep beams with large web openings in shear spans. A set of 18 specimens were fabricated and tested up to a failure to evaluate the structural performance in terms of cracking, deformation, and load-carrying capacity. All tested specimens were with 1500-mm length, 500-mm cross-sectional deep, and 150-mm wide. Parameters that studied were opening size, opening location, and the strengthening factor. Two deep beams were implemented as control specimens without opening and without strengthening. Eight deep beams were fabricated with openings but without strengthening, while

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Publication Date
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
International Studies Concerning Teachers’ Attitudes towards the Inclusion of Students with Special Educational Needs: Review of Literature
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Over the years, the issue of inclusion of students with special educational needs (SEN) in mainstream schools is controversial worldwide. Evidence from research argues that without a positive teachers’ attitude towards the inclusion of students with SEN in mainstream schools, the successful implementation of inclusion is most likely doubtable. The aim of this paper is to understand teachers’ attitudes towards the inclusion of students with SEN in mainstream schools from different perspectives and from different contexts. The conclusion drawn in this review can be that teachers’ attitude is the most important key towards the appropriate inclusion implementation in mainstream schools. The disparity of teachers’ attitudes towards th

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Publication Date
Wed Jun 11 2008
Journal Name
Journal Of Al-nahrain University
ANALYSIS OF A MOLECULAR DYNAMICS SIMULATION OF THE ACETYLCHOLINESTERASE ENZYME AND ITS COMPLEX WITH (AXILLARIDINE-A) INHIBITOR
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Molecular dynamics (MD) simulations were carried out in order to investigate the binding mode of axillaridine-A at the active site of human acetylcholinesterase (AChE) enzyme. 2.0 nanosecond of MD simulations was made for the protein and the complex to dynamically explore the active site and the behavior of the ligand at the peripheral AChE binding site. These calculations for the enzyme alone showed that the active site of AChE is located at the bottom of a deep and narrow cavity whose surface is lined with rings of aromatic residues and Tyr72 is almost perpendicular to the Trp286 ring and forms a stable - interaction. The size of the active site of the complex decreases with time due to increase the interaction. Axillaridine-A forms

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Publication Date
Fri May 01 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
Relationship of some fitness elements with the performance of lifting the iron ball (weight) by gliding method
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AS Muhsen, International Journal of Psychosocial Rehabilitation (1475-7192), 2020 - Cited by 1

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Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Effect of Polyurethane Resin Additives on the Impact Toughness of Epoxy Resin Reinforced with woven roving Glass
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I mpact strength for Epoxy/Polyurethane, Blends and their composites with two
layers of Glass fibers (0-90) are calculated.
The impact strength of the blends and composites decrease with increasing weight
by weisht percentage of polyurethane . This result is attributed to the high elasticity
of PU , and to the immiscibility between the polymer blends as well as the fiber
delaminates

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Publication Date
Wed Mar 04 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Computed tomographic localization of infraorbital foramen position and correlation with the age and gender of Iraqi subjects
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Background: The Infraorbital foramen is an anatomical structure with an important location in the maxilla, position of foramen in maxillofacial area is necessary in clinical situation requiring regional nerve blocks that are performed in children undergoing facial surgeries to avoid injury to corresponding nerve. The aim of study was to determine the position of the Infraorbital foramen and to correlate Infraorbital foramen position with age and gender using computed tomography. Subjects, Materials, and Methods: The sample consist of prospective study for 50 Iraqi subjects (21 male and 29 female) with age ranged from (5-17) years. The examination was performed on Multi – Slice Spiral Tomography scanner in Al-Karakh General Hospital. Using

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