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joe-2090
Experimental Study For a Laminar Natural Convection Heat Transfer From an Isothermal Heated Square Plate With and Without Circular Hole
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An experimental investigation of natural convection heat transfer from an isothermal horizontal,vertical and inclined heated square flat plates with and without circular hole, were carried out in two cases, perforated plates without an impermeable adiabatic hole "open core" and perforated plates with an impermeable adiabatic hole "closed core" by adiabatic plug. The experiments covered the laminar region with a range of Rayleih number of (1.11x106 ≤RaLo≤4.39x106 ), at Prandtle number (Pr=0.7). Practical experiments have been done with variable inclination angles from horizon (Ф=0o ,45o,90o,135oand 180o),facing upward (0o≤Ф<90o), and downward (90o
≤Ф<180o). The results showed that the temperature gradient increases while the thermal boundary layer thickness decreases when Grashof number and perforation ratio (m) increase . The temperature gradient for inclined position facing upward is less than facing downward,while the thermal boundary layer thickness is greater. The temperature gradient decreases while the thermal boundary layer thickness increases for perforated plates with an adiabatic core as compared with perforated plates without an adiabatic core. The value of average Nusselt number increases with increasing perforation ratio, and Grashof number for all specimens with and without an adiabatic core, also increases by increase in inclination of plates approaching the higher value at vertical position (Ф=90o
), then decreases with increasing inclination of plates till horizontal position (Ф=180o). The average Nusselt number values for perforated plates with an adiabatic core are lower than for perforated plates without an adiabatic core for all perforation ratios. Maximum heat transfer rate occurs at perforated plate with perforation ratio of (m=0.1) without adiabatic core for vertical position (Ф=90o), at a range of Grashof number (1.576x106≤GrLo≤6.292x106 ), while the rate of heat transfer decreases with increasing perforation ratio for plates with and without adiabatic core for decrease in heat transfer rate area. The rate of heat transfer for
perforated plates with circular hole is more than for perforated plates with square hole at the same perforation ratios (m=0.1,0.16,0.24 and 0.36). It found that the lack of core flow decreases the overall heat transfer rate by (6.477%) . There was a good agreement for the experimental present work results compared with other pervious results . 

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Publication Date
Wed Jan 08 2025
Journal Name
Journal Of Al-rafidain University College For Sciences ( Print Issn: 1681-6870 ,online Issn: 2790-2293 )
Utilizing the Error Correction Model to Investigate the Impact of Fluctuations in Bank Deposits on the Money Supply
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This paper assesses the impact of changes and fluctuations in bank deposits on the money supply in Iraq. Employing  the research constructs an Error Correction Model (ECM) using  monthly time series data from 2010 to 2015. The analysis begins with  the Phillips-Perron unit root test to ascertain the stationarity of the  time series and the Engle and Granger cointegration test to examine  the existence of a long-term relationship. Nonparametric regression functions are estimated using two methods: Smoothing Spline and M-smoothing. The results indicate that the  M-smoothing approach is the most effective, achieving the shortest adjustment period and the highest adjustment ratio for short-term disturbances, thereby facilitating a return

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Publication Date
Mon Jul 01 2024
Journal Name
المجلة العلمية لعلوم وفنون الرياضة
العلاقة بين طول الذراع وبعض المتغيرات البايوكينماتيكية في سباحة الفراشة (50 متر) لسباحي المنتخب الوطني
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Competitive swimming is a highly researched area and technological developments have aided advances in the understanding of the biomechanical principles that underpin these elements and govern propulsion. Moreover, those working in the sports field especially in swimming are interested in studying, analyzing, evaluating and developing motor skills by diagnosing the strengths and weaknesses of the skill, and accordingly, coaches and specialists correct these errors. The researchers chose this (Butterfly swimming) and the (arm length) is an important variable because the success of the stroke is greatly dependent on the propulsion generated from the arm pull, and swimmers with a longer arm span have a mechanical advantage with the resulting f

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Publication Date
Tue Mar 22 2022
Journal Name
Journal Of Al-turath University College
The Turkish role in the US-Iran Crisis (2017-2020)
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New developments imposed different patterns of interactions between major international powers and Iran during 2018, ranging to varying degrees between cooperation and tension, the most important of which is the new measures taken by the United States to withdraw from the nuclear agreement and impose new US sanctions on Iran, which in turn insisted on not responding to pressure to which they are exposed to make changes in their policies and to negotiate again about the main contentious files, especially the nuclear program and ballistic missiles, and the roles they play for crisis countries, especially supporting some armed organizations in Syria, Lebanon, Iraq and Yemen. These differences have put the international forces before difficult

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Publication Date
Sat Sep 30 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Accurate Petrophysical Interpretation of Carbonate using the Elemental Capture Spectroscopy (ECS)
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Elemental capture spectroscopy (ECS) is an important tool in the petroleum industry for determining the composition and properties of rock formations in a reservoir. Knowledge of the types and abundance of different minerals in the reservoir is crucial for accurate petrophysical interpretation, reservoir engineering practices, and stratigraphic correlation. ECS measures the elemental content of the rock, which directly impacts several physical properties that are essential for reservoir characterization, such as porosity, fluid saturation, permeability, and matrix density. The ability to accurately determine these properties leads to better reservoir mapping, improved production, and more effective resource management. Accurately de

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Publication Date
Sun Dec 05 2010
Journal Name
Baghdad Science Journal
On Semi-p-Compact Space1
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The purpose of this paper is to introduce a new type of compact spaces, namely semi-p-compact spaces which are stronger than compact spaces; we give properties and characterizations of semi-p-compact spaces.

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Publication Date
Sun Jan 01 2017
Journal Name
Brazilian Journal Of Analytical Chemistry
Determination of insecticides in different commercialformulations by Gradient HPLC
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A simple, accurate and rapid method for separation and determination of most commonly usedinsecticides in Iraq [thiamethoxam (Thi), imidacloprid (Imi), indoxacarb (Ind), and abamectin (Aba)] ispresented. The separation was performed by gradient reversed-phase high performance liquidchromatography on a C18 stationary phase column. The method was developed and validated. The-1mobile phase was a mixture of acetonitrile and water using gradient flow. The flow rate was 1.0 mL min .The optimum temperature of separation was 25 ºC. The detection was performed at multiple wavelengths.The analysis time was up to 10.5 minutes with retention times of 3.221, 3.854, 6.385, and 9.452 min for-1the studied insecticides. The linearity was in the range of 0.

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Publication Date
Tue Nov 01 2022
Journal Name
Alustath
Metrical Phonology in Modern Arabic Poetry
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Providing stress of poetry on the syllable-, the foot-, and the phonological word- levels is one of the essential objectives of Metrical Phonology Theory. The subsumed number and types of syllables, feet, and meters are steady in poetry compared to other literary texts that is why its analysis demonstrates one of the most outstanding and debatable metrical issues. The roots of Metrical Phonology Theory are derived from prosody which studies poetic meters and versification. In Arabic, the starting point of metrical analysis is prosodic analysis which can be attributed to يديهارفلا in the second half of the eighth century (A.D.). This study aims at pinpointing the values of two metrical parameters in modern Arabic poetry. To

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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
USING SENSITIVITY ANALYSIS IN DETERMINING THE OPTIMAL&EFFICIENT PRODUCTION PLANS IN GREENHOUSES IN ASSOCIATION OF AL-WATAN UNDER CONDITION OF RISK &UNCERTAINTY
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 The objectives of this research are to determine and find out the reality of crops structure of greenhouses in association of Al-Watan  in order to stand on the optimal use of economic resources available for the purpose of reaching a crop structure optimization of the farm that achieves maximize profit and gross and net farm incomes , using the method of linear programming to choose the farm optimal plan with the highest net income , as well as identifying production plans farm efficient with (income - deviation) optimal (E-A) of the Association and derived, which takes into account the margin risk wich derived from each plan using the model( MOTAD), as a model of models of linear programming alternative programming m

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Publication Date
Sun May 17 2015
Journal Name
Journal Of Physical Education
دراسة تحليلية مقارنة، لبعض المتغيرات الكينماتيكية، في أداء مهارة(Nick shot) الأمامية العكسية، بين لاعبي المنتخب العراقي والمصري، للشباب في الإسكواش
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هدفت الدراسة الى التعرف على مستوى استخدام إدارة المعرفة و تكنولوجيا المعلومات لدى القيادات الإدارية تُعدّ لعبة الإسكواش من الألعاب الفردية، وواحدة من ألعاب المضرب، والتي تمتاز بالسرعة والحركة الدائمة في داخل القاعة، ولعل أهم ما يميز هذه اللعبة المتعة التي يشعر بها اللاعبون الممارسون لها، لأنها تجبر ممارسيها على الحركة المستمرة عن طريق تبادل لعب الكرة، وتتميز بالتحدي المباشر، وتتطلب اليقظة والحرص وال

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Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
The Role of Annealing Temperature on the Optical Properties of Thermally Deposited CdTe Films
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A polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real p

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