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Effect of Using Combined Square Nozzle & winglet with Helical Tape on Thermal Characteristics in Tube Heat Exchanger
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Influence of combined square nozzle with helical tape inserted in a constant heat flux tube on heat transfer enhancement for turbulent airflow for Reynolds number ranging from 7000 to 14500 were investigated experimentally. Three different pitch ratios for square nozzle (PR = 5.8, 7.7 and 11.6) according to three different numbers of square nozzle (N = 3, 4 and 5) and constant pitch ratios for helical tape were used. The results observed that the Nusselt number and friction factor for combination with winglets were found to be up to 33.8 % and 21.4 %, respectively higher than nozzle alone for pitch ratio PR=5.8. The maximum value of thermal performance for using combination with winglets was about 1.351 for pitch ratio= 5.8. Nusselt number and friction factor correlations from experimental data were developed for turbulent flow.

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Publication Date
Fri Jan 01 2021
Journal Name
Turkish Journal Of Field Crops
Effect of melatonin on the morphological and physiological characteristics of Vigna radiata L. plant exposure to drought stress conditions
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A field experiment was conducted in the growth season 2019-2020 at the botanical garden of the Biology Department at the College of Education for Pure Sciences/Ibn Al-Haitham, University of Baghdad-Iraq. The experiments’ purpose is to determine the effects of different melatonin concentrations on some morphological and physiological characteristics of mung (Vigna radiata L.) plant under the influence of three periods of drought (5, 10, 15 days). The results were showed that the increasing of water stress periods had significant effects in the reducing rates of the studied characteristics, especially at the period 15 days. The external treatment of different concentrations of melatonin reduced the drought effects and that’s led to signif

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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Engineering
Nonlinear Behavior of Self -Compacting Reinforced Concrete Two-Way Slabs with Central Square Opening under Uniformly Distributed Loads
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This research is carried out to investigate the behavior of self-compacting concrete (SCC) two-way slabs with central square opening under uniformly distributed loads. The experimental part of this research is based on casting and testing six SCC simply supported square slabs having the same dimentions and reinforcement. One of these slabs was cast without opening as a control slab. While, the other five slabs having opening ratios (OR) of 2.78%, 6.25%, 11.11%, 17.36% and 25.00%. From the experimental results it is found that the maximum percentage decrease in cracking and ultimate uniform loads were 31.82% and 12.17% compared to control slab for opening ratios (OR

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Publication Date
Sat Jun 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Predicting of Temperature Distribution in Direct Contact Heat Transfer
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An experimental and theoretical investigation of three phase direct contact heat transfer by evaporation of refrigerant drops in an immiscible liquid has been carried out. Refrigerant Rl2 and R134a were used for the dispersed phase, while water and brine were the immiscible continuous phase. A numerical analysis is presented to predict the temperature distribution throughout the circular test column radially and axially is achieved. Experimental measurements of the temperature distribution have been compared with the numerical results and are discussed .A comparison between the experimental and theoretical results showed acceptable agreement and applicability of the derived equations. Comparison with other related work showed similar beh

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Publication Date
Thu Jul 23 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of addition of hydroxyapatite microscopic fillers on surface roughness and some mechanical properties of heat cured acrylic resin
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Background: this study aimed to evaluate the effect of addition of hydroxyapatite micro filler in three concentrations (5%, 10%, 15%) on surface roughness, impact strength, flexural strength and hardness. Material and methods: One hundred sixty acrylic samples were used in this study,40 samples were used for each test(impact strength ,flexural strength ,hardness and surface roughness).The test group divided into four subgroups(n=10) for controlgroup,5%,10% ,15%H,A.concentration addition groups .Impact testing device, flexural strength testing device, shore hardness tester and profilometer device were used to measure the four tests examined in this study. Results: the results showed a significant increase in impact strength, hardness in all

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Publication Date
Thu Jul 23 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The effect of addition of untreated and oxygen plasma treated polypropylene fibers on some properties of heat cured acrylic resin
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Background: The polymethyl methacrylate is the most reliable material for the construction of complete and partial dentures, despite satisfying esthetic demand itsuffered from having unsatisfactory properties like impact strength and transverse strength. This study was designed to improve the impact strength and transverse strength of heat cure acrylic resin by adding untreated and oxygen plasma treated polypropylene fibers and investigate the effect of this additive on some properties of acrylic resin materials. Materials and methods: Untreated and oxygen plasma treated polypropylene fibers was added to PMMA powder by weight 2.5 %. Specimens were constructed and divided into 5 groups according to the using tests; each group was subdivided

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Publication Date
Mon Oct 06 2014
Journal Name
Journal Of Educational And Psychological Researches
The Effect of a Suggested Translation Strategy on ESP Learners’ Achievement in Translation
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In spite of the disappearing of a clear uniform textbook for teaching ESP at different departments and different colleges in both scientific and humanistic studies, the practitioners at those departments and colleges have to teach translation as one of the important requirements to pass the English language exam. The lack of defined translation activities is a noticeable problem therefore; the problem of teaching translation is diagnosed in that the students lack the ability to comprehend the text in English language and other translation knowledge and skills.

The study aims to suggest a translation strategy and then find out the effect of the translation strategy on ESP learners’ achievement in translation. A sample of 50 stud

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Publication Date
Fri Jun 30 2023
Journal Name
The International Tinnitus Journal
Adenoidectomy and Endoscopic Myringotomy with and without ventilation tube insertion for Treatment of Otitis Media with Effusion in 6-12 years old Children
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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Investigating the Influence of Precursor Concentration on the Photodegradation of Methylene Blue using Biosynthesized ZnO from Pometia pinnata Leaf Extracts
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The ZnO nanoparticles were synthesized at various precursor concentrations i.e. 0.05, 0.1, and 0.5 M by biosynthesis method based on Pometia pinnata Leaf Extracts. Initial nanoparticle concentration influenced the optical bandgap, shape, and structure of nanoparticles. The photodegradation process was carried out under UV illumination. The efficiency of MB degradation was determined by measuring the decrease in MB concentration and by analyzing the optical absorption at 663 nm recorded by UV-Vis spectroscopy. Results showed that the biosynthesized ZnO nanoparticles exhibited efficient photodegradation of MB, with a maximum degradation rate of 80% after 90 minutes of exposure to UV-C light. The study highlights the potential of Pometia pi

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Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Fixed Point Theorems in General Metric Space with an Application
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   This paper aims to prove an existence theorem for Voltera-type equation in a generalized G- metric space, called the -metric space, where the fixed-point theorem in - metric space is discussed and its application.  First, a new contraction of Hardy-Rogess type is presented and also then fixed point theorem is established for these contractions in the setup of -metric spaces. As application, an existence result for Voltera integral equation is obtained.  

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Impact Of Knowledge Innovation On Strategic Empowerment (Comparative Field Research)
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The Innovation Of Knowledge Is An Important And A Key Element In The Progress And Business Excellence Organizations, Therefore Requires Several Elements To Help Create And Implement And Move The Innovation Process Of Knowledge, Including The Strategic Empowerment Associated With The Element Of The Process Of Strategic Momentum Engine Driven Wheel Continuous Dynamic Innovation, And Focused Research Problem By Measuring The Availability Of Strategic Empowerment When Individuals From By Senior Departments And Ways To Help Organizations To Provide Empowerment Commensurate With The Requirements Of Achieving The Goals Of Time And Place Appropriate For The Individual, And The Importance Of Research Stems From The Importance Of The Varia

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