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The Effect of Fin Design on Thermal Performance of Heat Sink
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      An experimental and computational study is conducted to analyze the thermal performance of heat sinks and to pick up more profound information in this imperative field in the electronic cooling. One important approach to improve the heat transfer on the air-side of the heat exchanger is to adjust the fin geometry. Experiments are conducted to explore the impact of the changing of diverse operational and geometrical parameters on the heat sink thermal
performance. The working fluid used is air. Operational parameters includes: air Reynolds number (from 23597 to 3848.9) and heat flux (from 3954 to 38357 W/m
2 ). Conformational parameters includes: change the direction of air flow and the area of conduction/convection. Six . parallel plate heat sinks are fabricated and tested in small wind tunnel: flat plate, cross-cut, perforated, perforated cross-cut, zigzag and serpentine. Three-dimensional numerical simulations using commercial available FLUENT 15 software, based on the Navier–Stokes equations standard k-ε applied turbulence model and energy equation, are acquired for forced convection of air in same heat sinks under the same experimental conditions. It is found that the numerical prediction of base temperature is in good agreement with experimental data. Results show that the Reynolds number has a significant effect on the thermal performance of the system. With increasing free stream velocity, the heat transfer coefficient increases and consequently the thermal resistance decreases. Furthermore, it is found that the heat transfer coefficient and thermal resistance are depending on heat flux. From the comparison analysis of various geometries of heat sinks, the perforated-cut heat sink showed the best thermal performance indicated heights Nusselt number and heat transfer coefficient, lowest thermal resistance.

 
 

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Publication Date
Sun Jun 01 2025
Journal Name
Journal Of The College Of Languages (jcl)
Rebellious Self - A Reading in Madame Bovary's Character of Flubert and Hanna Konin by Amos Oz - Comparative study: האני המורדת - קריאה בדמותה של מאדאם בובארי של פלובר וחנה גונן של עמוס עוז – מחקר השוואתי
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The problem of rebellion is considered one of the features of rapid changes that a society undergoes in all spheres and directions of life, especially in the realm of social relations, customs, traditions, values, and principles. Rebellion may manifest itself in rebellion against oneself, against values or traditions, or against social or governmental authority. One may find that submission plays a vital role in all of these interactions. This study deals with the problem of rebellion in the works of two renowned authors: The French Gustave Flaubert and the Israeli Amos Oz, through two main characters who share similar qualities and traits. Emma Bovary and Henna Konin demonstrate this through their rebellion against themselves, their relati

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Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
Synthesis, Theoretical Study, and Biological Evaluation of Some Metal Ions with Ligand "Methyl -6-[2-(4-Hydroxyphenyl) -2-((1-Phenylethylidene) Amino) Acetamido] -2,2-Dimethyl-5—Oxo-1-Thia-4-Azabicyclo [3.2.0] Heptane-3-Carboxyylate
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Schiff base (methyl 6-(2- (4-hydroxyphenyl) -2- (1-phenyl ethyl ideneamino) acetamido) -3, 3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0] heptane-2-carboxylate)Co(II), Ni(II), Cu (II), Zn (II), and Hg(II)] ions were employed to make certain complexes. Metal analysis M percent, elemental chemical analysis (C.H.N.S), and other standard physico-chemical methods were used. Magnetic susceptibility, conductometric measurements, FT-IR and UV-visible Spectra were used to identified. Theoretical treatment of the generated complexes in the gas phase was performed using the (hyperchem-8.07) program for molecular mechanics and semi-empirical computations. The (PM3) approach was used to determine the heat of formation (ΔH˚f), binding energy (ΔEb), an

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Publication Date
Thu Mar 25 2021
Journal Name
International Journal Of Drug Delivery Technology
Synthesis, Structural Study, and Biological Activity Evaluation of VO(II), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) Complexes with New Schiff Base Ligand Derived from Pyrazine
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New Schiff base [3-(3-acetylthioureido)pyrazine-2-carboxylic acid][L] has been prepared through 2 stages, the chloro acetyl chloride has been reacting with the ammonium thiocyanate in the initial phase for producing precursor [A], after that [A] has been reacting with the 3-amino pyrazine-2-carboxilic acid to provide a novel bidentate ligand [L], such ligand [L] has been reacting with certain metal ions in the Mn(II), VO(II), Ni(II), Co(II), Zn(II), Cu(II), Hg(II), and Cd(II) for providing series of new metal complexes regarding general molecular formula [M(L)2XY], in which; VO(II); X=SO4,Y=0, Co(II), Mn(II), Cu(II), Ni(II), Cd(II), Zn(II), and Hg(II); Y=Cl, X=Cl. Also, all the compounds were characterized through spectroscopic techniques [

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Publication Date
Tue Jan 23 2018
Journal Name
Suleyman Demİrel University
ANALYZING POSTGRADUATE STUDENTS' USE OF PRAGMATIC FEATURES AND ARGUMENTATION IN THESIS WRITING: A CORPUS-BASED STUDY تحليل استخدام طلبة الدراسات العليا للسمات التداولية و الحجج في كتابة الرسائل العلمية : دراسة تعتمد تحليل البيانات المحوسبة
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This study addresses the issue of academic writing in English by comparing pragmatic argumentation in the writing of 40 graduate students studying at Iraqi universities (SSIU) with the writing of 40 graduate students studying at American universities (SSAU). In these 80 theses, six selected aspects of academic writing were analyzed: (a) paragraph structure, (b) length and construction of sentences, (c) organization of information in sentences, (d) vocabulary, (e) topic sentences, and (f) discourse markers. This study seeks to go beyond the traditional and often onedimensional analysis of pragmatics of argumentation in English academic writing to distinguish and describe different aspects of academic writing and their results when used by EF

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Publication Date
Sun Mar 01 2015
Journal Name
Baghdad Science Journal
Preparation and Spectral Characterization of New Azo Imidazole Ligand 2-[(2`-Cyano Phenyl) Azo]-4,5-Diphenyl Imidazole and its Complexes with Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg (II) Ions
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The preparation and spectral characterization of complexes for Co(II), Ni(II), Cu(II), Cd(II), Zn(II) and Hg(II) ions with new organic heterocyclic azo imidazole dye as ligand 2-[(2`-cyano phenyl) azo ]-4,5-diphenyl imidazole ) (2-CyBAI) were prepared by reacting a dizonium salt solution of 2-cyano aniline with 4,5-diphenyl imidazole in alkaline ethanolic solution .These complexes were characterized spectroscopically by infrared and electronic spectra along with elemental analysis‚ molar conductance and magnetic susceptibility measurements. The data show that the ligand behaves a bidantate and coordinates to the metal ion via nitrogen atom of azo and with imidazole N3 atom. Octahedral environment is suggested for all metal complex

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Publication Date
Sun Jan 26 2020
Journal Name
Journal Of Global Pharma Technology
Synthesis, Characterization of 2-azido-4-(azido (2-azido-2-( azido carbonyl)-1,3-dioxoian-4-yl)methyl)– 5-((R-azido (hydroxyl) methyl- 1,3-dioxole-2-carbonyl azide. ethanol. hydrate (L-AZD) with Some Metal Complexes
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The reaction oisolated and characterized by elemental analysis (C,H,N) , 1H-NMR, mass spectra and Fourier transform (Ft-IR). The reaction of the (L-AZD) with: [VO(II), Cr(III), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II)], has been investigated and was isolated as tri nuclear cluster and characterized by: Ft-IR, U. v- Visible, electrical conductivity, magnetic susceptibilities at 25 Co, atomic absorption and molar ratio. Spectroscopic evidence showed that the binding of metal ions were through azide and carbonyl moieties resulting in a six- coordinating metal ions in [Cr (III), Mn (II), Co (II) and Ni (II)]. The Vo (II), Cu (II), Zn (II), Cd (II) and Hg (II) were coordinated through azide group only forming square pyramidal

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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Using Earned Value Method in Project Control Applied research
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   There is no doubt that the project control function is very important for administration, so the project Management depends on to monitor and control the project. The project control integrated to the planning which is the base of the administration functions; planning, organizing, directing, and controlling. Without project control cannot be insure to fulfill the plan of the project by the budget and specified time. The project management apply many methods of control to achieve the goals of project which are cost, time, and required specifications. Earned Value Management one of control methods that used in the project by international companies.

Earned Value Method is used in the project o

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Publication Date
Thu Nov 19 2020
Journal Name
Indonesian Journal Of Chemistry
Determination of Eugenol in Personal-Care Products by Dispersive Liquid-Liquid Microextraction Followed by Spectrophotometry Using <i>p</i>-Amino-<i>N,N</i>-dimethylaniline as a Derivatizing Agent
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Two simple methods for the determination of eugenol were developed. The first depends on the oxidative coupling of eugenol with p-amino-N,N-dimethylaniline (PADA) in the presence of K3[Fe(CN)6]. A linear regression calibration plot for eugenol was constructed at 600 nm, within a concentration range of 0.25-2.50 μg.mL–1 and a correlation coefficient (r) value of 0.9988. The limits of detection (LOD) and quantitation (LOQ) were 0.086 and 0.284 μg.mL–1, respectively. The second method is based on the dispersive liquid-liquid microextraction of the derivatized oxidative coupling product of eugenol with PADA. Under the optimized extraction procedure, the extracted colored product was determined spectrophotometrically at 618 nm. A l

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Publication Date
Sun Jun 02 2024
Journal Name
مجلة المستنصرية لعلوم الرياضة
تأثير تمرينات خاصة لتطوير التحمل الخاص والاداء المهاري الدفاعي الفردي للاعبي بأعمار (14-16) سنة بكرة السلة
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The game of basketball (orange ball) is considered one of the fast and exciting games in the world. It is played by both sexes and different ages. It has Olympic and international championships and has various performance skills, including defensive ones. This game requires physical abilities that players must have for duties during matches, including special endurance that is compatible with... The peculiarity of the game is the changing rhythm and positions on the field. The importance of the research lies in the importance of special exercises to develop special endurance and its role in influencing the defensive skill performance of the players throughout the duration of the match.The problem of the research appeared in the decline in i

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
DIESEL PARTICULATE EMISSIONS EVALUATION FOR SINGLE CYLINDER ENGINE FUELLED WITH ETHANOL AND GAS-OIL SOLUTIONS
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Particulate matter (PM) emitted from diesel engine exhaust have been measured in terms of mass, using
99.98 % pure ethanol blended directly, without additives, with conventional diesel fuel (gas – oil),to
get 10 % , 15 %, 20 % ethanol emulsions . The resulting PM collected has been compared with those
from straight diesel. The engine used is a stationary single cylinder, variable compression ratio Ricardo
E6/US. This engine is fully instrumented and could run as a compression or spark ignition.
Observations showed that particulate matter (PM) emissions decrease with increasing oxygenate
content in the fuel, with some increase of fuel consumption, which is due to the lower heating value of
ethanol. The reduction in

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