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Enhancement of Heat Exchanger Performance by Using Dimpled Tube
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The enhancement of heat exchanger performance was investigated using dimpled tubes tested at different Reynolds numbers, in the present work four types of dimpled tubes with a specified configuration manufactured, tested and then compared performance with the smooth tube and other passive techniques performance. Two dimpled arrangements along the tube were investigated, these are inline and staggered at constant pitch ratio X/d=4, the test results showed that Nusselts number (heat transfer) of the staggered array is higher than the inline array by 13%.  The effect of different depths of the dimple (14.5 mm and 18.5 mm) has been also investigated; a tube with large dimple diameter enhanced the Nusselts number by about 25% for the range of Reynolds number between 4000- 20000. The overall enhancement ratio was used to differentiate the passive technique and comparison of different configurations for the technique itself, the result depicted that the 10 mm dimple diameter with a pitch ratio of X/d= 4 gives better performance than the static mixer and twisted tape techniques. The overall enhancement ratio of the 10 mm dimple diameter is varied from (1.21 to 1.65) that means good performance for a range of Reynolds numbers (4000-20000). This indicates that 21- 65 % of heat transfer area can be saved at the same pumping power compared with the smooth tube heat exchanger. 

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Publication Date
Thu Oct 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Project Scheduling By using Goals Programming – An Applied Research In Modern Village Project (Residential Building Aspectin In Wasit Governorate)
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One of the most important challenges facing project management at present time is to ensure project accomplishment in spite of the specific restrictions like the specific time the financial resources specialized to do the project ; which require an accurate consideration for time and cost . the modern village project (residential building aspect) is one of the great project that ministry of agriculture is trying to do Wasit  governorate it is chosen as the work in this project is dilatory for that is being studied in term of some modern mathematical and scientific methods like critical path method (CPM)which is one of the project management and scheduling methods to know the time needed to accomplish residential building pro

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Publication Date
Sun Oct 11 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Tensile force measurement by using different lingual retainer wires, bonding materials types and thickness (A comparative in vitro study)
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Background: The bonded orthodontic retainer constructed from multistrand wire and composite is an efficient esthetic retainer, which can be maintained long-term. Clinical failures of bonded orthodontic retainers, most commonly at the wire/composite interface, have been reported. This in vitro investigation aimed to evaluate the tensile forces of selected multistrand wires and composite materials that are available for use in the construction of bonded fixed retainers. Materials and Methods: The study sample includes 120 wires with three types of retainer wires (3 braided strands\ Orthotechnology, 8 braided strands\ G&H Orthodontics, 6 coaxial strands\ Orthoclassic wires), two types of adhesive (flowable\ Orthotechnology, non flowable\ G&H O

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Publication Date
Sat Jan 01 2022
Journal Name
1st Samarra International Conference For Pure And Applied Sciences (sicps2021): Sicps2021
Analysis the average lattice strain in the crystal direction (hkl) in MgO nanoparticles by using modified Williamson-Hall method
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In this work ,the modified williamos-Hall method was used to analysis the x-ray diffraction lines for powder of magnesium oxide nanoparticles (Mgo) .and for diffraction lines (111),(200),(220),(311) and (222).where by used special programs such as origin pro Lab and Get Data Graph ,to calculate the Full width at half maximum (FWHM) and integral breadth (B) to calculate the area under the curve for each of the lines of diffraction .After that , by using modified Williamson –Hall equations to determin the values of crystallite size (D),lattice strain (ε),stress( σ ) and energy (U) , where was the results are , D=17.639 nm ,ε =0.002205 , σ=0.517 and U=0.000678 respectively. And then using the scherrer method can by calculated the crystal

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Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Nonlinear Analysis And Applications
Big data analysis by using one covariate at a time multiple testing (Ocmt) method: Early school dropout in iraq
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Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
The Calculation of the Charge Density Distributions and the Longitudinal Form Factors of 10 B Nucleus by Using the Occupation Numbers of the States
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The charge density distributions of 10 B nucleus are calculated using the
harmonic oscillator wave functions. Elastic and inelastic electron scattering
longitudinal form factors have been calculated for the similar parity states of 10B
nucleus where a core of 4He is assumed and the remaining particles are
distributed over 3/ 2 1p and 1/ 2 1p orbits which form the model space.
Core-polarization effects are taken into account. Core-polarization effects are
calculated by using Tassie model and gives good agreement with the measured
data.

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Publication Date
Fri Jul 28 2023
Journal Name
Journal Of Optics
Estimated the nanoparticles size of CdS from UV–Vis spectrum absorption by effective mass approximation model (EMA) using capping and complex agent
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Publication Date
Fri Aug 30 2024
Journal Name
Iraqi Journal Of Science
The Dissipation of the Kinetic Energy for 2D Bounded Flow by Using Moment-Based Boundary Conditions with Burnett Order Stress for LBM
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     In this article, the lattice Boltzmann method with two relaxation time  (TRT)  for the  D2Q9 model is used to investigate numerical results for 2D flow. The problem is performed to show the dissipation of the kinetic energy rate and its relationship with the enstrophy growth for 2D dipole wall collision. The investigation is carried out for normal collision and oblique incidents at an angle of . We prove the accuracy of moment -based boundary conditions with slip and Navier-Maxwell slip conditions to simulate this flow. These conditions are under the effect of Burnett-order stress conditions that are consistent with the discrete Boltzmann equation. Stable results are found by using this kind of boundary condition where d

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Publication Date
Sun Oct 11 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Diagnosis and localization of the maxillary impacted canines by using dental multi-slice computed tomography 3D view and reconstructed panoramic 2D view
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Background: Diagnosis and treatment planning can be difficult with conventional radiographic methods as the orthodontic-surgical management of impacted canines requires accurate diagnosis and precise localization of the impacted canine and the surrounding structures. This study was aimed to localize and evaluate weather there is any differences in the diagnostic information provided by multi-slice computed tomography three dimensional volumetric CT images and two dimensional reconstructed panorama images (derived from CT) in subjects with impacted maxillary canines. Materials and Methods: Thirty patients including 24 female and 6 male with mean age of 18 years with suspected unilaterally or bilaterally impacted maxillary canines were evalu

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Publication Date
Tue Feb 11 2025
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Enhancing the Antibacterial Activity of Ciprofloxacin Against Klebsiella pneumoniae by Inhibiting the AcrAB-TolC Efflux Pump System Using Phenylalanine-arginine β-Naphthylamide
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Background: Klebsiella pneumoniae shows varying degrees of resistance to antibiotic treatment; this resistance arises from multiple mechanisms, including the increased expression of multidrug (MDR) efflux pumps. An efflux pump inhibitor (EPI) is required to overcome this challenge and restore the effectiveness of antibiotics against the present MDR K. pneumoniae. Objective: To investigate the synergistic effect of the EPI Phenylalanine-Arginine β-Naphthylamide (PaβN) and Ciprofloxacin (CIP) on the expression of efflux pump genes AcrAB-TolC, isolated from CIP-resistant K. pneumoniae. Methods: 50 isolates of K. pneumoniae were collected from five different hospitals in Baghdad, Iraq. The minimum inhibitory concentration (MIC) values

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Publication Date
Sun May 05 2024
Journal Name
المؤتمر الثالث للعلوم الانسانية
هدف التنمية المستدامة في تحسين جودة التعليم (العراق كحالة دراسية في مجال التعليم الالكتروني)
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لدى التنمية المستدامة العديد من الأهداف، ويبرز تحسين جودة التعليم من هذه الأهداف إذ تسعى جميع دول العالم لتطبيقه، ونشاهد دولة العراق التي تعاني من تراجع في مستوى التعليم بشكل غير اعتيادي وارتفاع عدد الامية والهروب من المدارس وعدم وجود أبنية دراسية جديدة للطلاب. وفي الوقت نفسه نشاهد الحكومة العراقية الحالية تبذل جهدها من أجل تحسين جودة التعليم وأنها توفر الوظائف للمتفوقين والكفوءات والمجتهدين، وإنها توفر ك

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