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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
Sat May 02 2020
Journal Name
Karbala Journal Of Physical Education Sciences
The effect of using a designed device to develop the technical performance of the descending landing skill facing with half a cycle on the parallel device of the technical men's
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AS Salman, SK Hameed…, Karbala Journal of Physical Education Sciences, 2020

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Publication Date
Wed May 03 2017
Journal Name
Journal Of Physical Education
تأثير تمرينات علاجية في تحسين مرونة الجذع وانعكاسها على آلام اسفل الظهر لذوي الاعاقة البدنية
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Publication Date
Wed Aug 03 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The pioneering trend in managing health institutions and its impact on improving the quality of services : A case study in some institutions of the Iraqi Ministry of Health
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This study seeks to identify the role that the leadership trend plays in the management of health institutions in Iraq and its impact on improving the quality of the health service provided by analyzing some opinions of affiliates working in the Iraqi health sector where a survey list was used as a main tool for collecting primary data, as it was subjected to this analysis ( 60) of the medical staff, of whom (40) are doctors and (20) are affiliated with the rank of assistant physician, and (60) members of the administrative cadre have undergone their various job ranks and administrative specializations (department manager, auditor, observer, accountant, statistician, secretary). Reliance on statistical software (spss) in data ana

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Publication Date
Mon Oct 12 2026
Journal Name
Journal Of Baghdad College Of Dentistry
An evaluation of canal transportation and centering ability at different levels of root canals prepared by self-adjusting file using computed tomography (A comparative study)
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Background: The new concepts and technologies continue to change the dynamics of endodontic practices in the world. Rapid and significant changes in techniques, instrument design, and the type of metals used to manufacture endodontic instruments which have been made during the last few years in an attempt to overcome canal preparation errors. The purpose of this study is to measure and compare canal transportation and centering ability of Self Adjusting File with two rotary nickel-titanium (Ni-Ti) systems, ProTaper and BioRaCe at different levels. Material and Methods: Forty five distal roots of mandibular first molars with moderate curvature were selected using Schneider method. Roots were divided randomly into 3 groups of 15 each and were

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Publication Date
Mon Oct 12 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Quantitative detection and correlation of Epstein - Barr Virus in plasma with gingivitis and severity of chronic periodontitis by using real-time polymerase chain reaction technique
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Background: The main purpose of this study is to find if there is any correlation between the level of C-reactive protein (CRP) in gingival crevicular fluid with its serum level in chronic periodontitis patients and to explore the differences between them according to the probing depth. Materials and methods: Forty seven male subjects enrolled in this study. Thirty males with chronic periodontitis considered as study group whom further subdivided according to probing depth into subgroup 1 with pocket depth ≤6mm, subgroup 2 with pocket depth >6mm. The other 17 subjects considered as controls. For all subjects, clinical examination where done for periodontal parameters plaque index (PLI), gingival index (GI), bleeding on probing (BOP),

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Publication Date
Tue Jan 31 2017
Journal Name
Journal Of Engineering
A Study on the Removal of Direct Blue 71 Dye From Textile Wastewater Produced From State Company of Cotton Industries by Electrocoagulation Using Aluminum Electrodes
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The removal of direct blue 71 dye from a prepared wastewater was studied employing batch electrocoagulation (EC) cell. The electrodes of aluminum were used. The influence of process variables which include initial pH (2.0-12.0), wastewater conductivity (0.8 -12.57) mS/cm , initial dye concentration (30 -210) mg/L, electrolysis time  (3-12) min, current density (10-50) mA/cm2   were studied in order to maximize the color removal from wastewater. Experimental results showed that the color removal yield increases with increasing pH until pH 6.0 after that it decreased with increasing pH. The color removal increased with increasing current density, wastewater conductivity, electrolysis time, and decreased with increasing the concen

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Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Addition of Combination of Plasma Treated Polyester and Polyamide Fibers on Surface Roughness and Some Mechanical Properties of Heat Cured Acrylic Resin
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Publication Date
Thu Mar 15 2018
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Addition of Combination of Plasma Treated Polyester and Polyamide Fibers on Surface Roughness and Some Mechanical Properties of Heat Cured Acrylic Resin
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Background: Poly (methyl methacrylate) has several disadvantages (poor mechanical properties) like impact and transverse strength. In order to overcome these disadvantages, several methods were used to strengthen the acrylic resin by using different fibers or fillers. This study was conducted to evaluate the effect of Plasma treatment of the fiber on mechanical properties Poly (methyl methacrylate) denture base material. Materials and methods: Specimens were prepared from poly methyl metha acrylic (PMMA) divided according to present of fiber into 4 groups (first group without fiber as control group, second group with Plasma treated polyester fibers, third group with Plasma treated polyamide fibers and fourth group Plasma treated combination

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Publication Date
Tue Dec 01 2020
Journal Name
Baghdad Science Journal
Determination of Phosphodiesterase Type 5 Enzyme (PDE-5) Inhibitors and Analogues as Adulterants in Selected Herbal Products using Gas Chromatography–Electron Impact-Mass Spectrometer (GC-EI-MS)
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       Sildenafil, tadalafil, and vardenafil are phosphodiesterase type 5 enzyme (PDE-5) inhibitors used for the treatment of male erectile dysfunction. This present study aims to investigate 55 herbal products indicated for men’s sexual health from the Malaysian market for adulteration of PDE-5 inhibitors and analogues. The screening and identification of 20 PDE-5 inhibitors and analogues in herbal products of various forms (powder, capsules, tablets, and pastels) were conducted using gas chromatography–electron impact-mass spectrometer (GC-EI-MS). The analysis has shown that 19 herbal products were adulterated with PDE-5 inhibitors and analogues. Unique ion fragmentations and the presence of molecular

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Publication Date
Thu Sep 06 2018
Journal Name
Al-khwarizmi Engineering Journal
Bone Defect Animal Model for Hybrid Polymer Matrix Nano Composite as Bone Substitute Biomaterials
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Addition of bioactive materials such as Titanium oxide (TiO2), and incorporation of bio inert ceramic such as alumina (Al2O3), into polyetheretherketone (PEEK) has been adopted as an effective approach to improve bone-implant interfaces. In this paper, hot pressing technique has been adopted as a production method. This technique gave a homogenous distribution of the additive materials in the proposed composite biomaterial. Different compositions and compounding temperatures have been applied to all samples. Mechanical properties and animal model have been studied in all different production conditions. The results of these new TiO2/Al2O3/PEEK biocomposites with different

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