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Discharge performance assessment of a vertical double-pipe latent heat storage unit equipped with circular Y-shaped fins
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This paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the solidification time is inversely proportional to the fin's length. The heat release rate for the case with the longest fins (stem length of 10 mm) is 39 W, almost 2.8 times higher than that with the fins' stem length of 5 mm. The case with the tributary's angle of 22.5o solidified in 55 min, faster than the other studied angles. Increasing the number of fins significantly affects the solidification time and discharging rate. By increasing the number of fins from 3 to 9, the heat transfer rate improves by 194%. The advantages of circular Y-shaped fins are well known in heat transfer applications and therefore are characterized toward higher performance in this study for the first time during the solidification process.

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Publication Date
Mon Apr 04 2022
Journal Name
Journal Of Educational And Psychological Researches
The Degree of Availability of the Dimensions of Organizational Immunity Systems t the University of Tabuk in KSA from the Perspectives of Academic Leaders
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This study aims to investigate the academic leaders’ perceptions towards the degree of availability of the dimensions of organizational immunity systems at the University of Tabuk, as well as to reveal the statistically significant differences between the average responses of the study sample members about the degree of availability of these dimensions at their university due to the variables of (gender, leadership position, and college specialization). To achieve the objectives of the study, a descriptive survey method was used. The study population consisted of (200) male and female leaders who were academic leaders at the University of Tabuk. A questionnaire was used as a tool for collecting data, which its validity and reliability

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Publication Date
Sun Apr 01 2018
Journal Name
Al–bahith Al–a'alami
The propaganda content of the elements of expression in the face of the promotion of terrorist thought: (Military information of the popular crowd model)
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The propaganda war is one of the most dangerous weapons used in various conditions of war and peace within any intellectual, political or military conflict to be targeted by multiple social groups and their effects on the intellectuals to change the viewpoints at the local and global level, including the use of technical treatment of the audio and visual medium, The impact of the psychological dimensions of the arms in the confrontation and spread terror in the ranks of the enemies and in the forefront of what Iraq faces in its battle against the And the use of it as a propaganda content contributes to the development of the spirit of tranquility and tranquility in the hearts of Iraqis and the return of the right to the owners “th

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Publication Date
Mon Dec 31 2018
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
ESTIMATION OF LEAD ELEMENT IN THE BLOOD OF TRAFFIC POLICE IN THE CITY OF BAGHDAD.: ESTIMATION OF LEAD ELEMENT IN THE BLOOD OF TRAFFIC POLICE IN THE CITY OF BAGHDAD.
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The current study aimed to determine the relation between the lead levels in the blood traffic men and the nature of their traffic work in Baghdad governorate. Blood samples were collected from 10 traffic men and the age about from 20-39 year from Directorate of Traffic Al Rusafa/ Baghdad and 10 samples another control from traffic men too with age 30-49 year and they livedrelatively in the clear cities or contained of Very few traffic areas. The levels of lead in blood estimated by used Atomic Absorption Spectrometry.
The result stated that there is no rising of the levels of lead in blood of traffic men Lead concentration was with more a range from 14 ppm in Traffic police are not healthy They are within the permissible limits, Ap

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Publication Date
Thu Jun 30 2022
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
STUDY OF YIELD AND ITS COMPONENTS OF INTRODUCED VARIETIES OF MAIZE UNDER DIFFERENT PLANTING DENSITIES: STUDY OF YIELD AND ITS COMPONENTS OF INTRODUCED VARIETIES OF MAIZE UNDER DIFFERENT PLANTING DENSITIES
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In order to evaluate the performance of introduced varieties of maize and test them under different levels of plant density, and to determine which of the introduced varieties give a high yield and at what plant density, a field experiment was carried out at Station A in the Department of Field Crops- College of Agricultural Engineering Sciences - University of Baghdad- Jadiriyah, for the fall season 2021, the RCBD design was used with four replications, in a split plot arrangement, the three plant densities (50.000, 70.000, and 90.000 Plant s ha-1) were the main plates, while the varieties represented the secondary factor, which is six varieties of maize, class 2 = 5783 DKC, Class 3 = 6315 DKC, Class 4= 6590 DKC, whic

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Publication Date
Tue Dec 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation of the efficiency and effectiveness of the accounting system of the Department of Missions and Cultural Relations (*) at the Office of the Ministry of Higher Education and Scientific Research
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The evaluation and efficiency and effectiveness of account system for the department of delegation and cultural Relationships in the center of ministry of higher Education and Scientific research Considered as a very important and active subjects in the modification of accounting system in this department and to develop it and make it able to make available important and accurate information for the planning requirements and monetary and evaluation performance and to make decisions, besides to develop the performance of Iraqi Cultural departments working abroad and to render its role effective to serve the students of higher education in the progressive Countries to facility its growing in scientific and professional and technica

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Crossref
Publication Date
Sun Jan 20 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
EVALUATION OF SOME BIOChEMICAL LEVELS IN THE SERUM OF PROFESSORS EXPOSED TO CHEMICALS IN THE LABORATORIES OF THE UNIVERSITY OF SAMARRA: EVALUATION OF SOME BIOChEMICAL LEVELS IN THE SERUM OF PROFESSORS EXPOSED TO CHEMICALS IN THE LABORATORIES OF THE UNIVERSITY OF SAMARRA
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A chemical study was carried out to evaluate the efficiency of the liver enzyme concertation and uric acid level and its antagonists in the serum of the professors exposed to chemicals in the laboratories of the University of Samarra and their comparison with the healthy people. The research included 25 samples of the exposed professors and 20 samples as a group of officers.

              The results of the current study showed a significant increase in the level of   AST, ALT in the serum of professors exposed to chemicals compared to healthy people. The results showed no significant increase in

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Measurement of Users Satisfaction from the Automatic Retrieval Service of the Dissertation in the Central Library of the University of Baghdad: Measurement of Users Satisfaction from the Automatic Retrieval Service of the Dissertation in the Central Library of the University of Baghdad
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Abstract
This study aims to evaluated the user satisfaction of retrieval services
concerning to universities thesis and dissertations in university dissertation
unit of Baghdad Library for achieving the following objectives:
1- Evaluating the performance of this unit (thesis unit of Baghdad University
Library) regarding to users opinion.
2- Recognizing the reasons in this unit behind the case of non satisfaction of
its users and trying to find the suitable solutions.
To achieve those two objectives, the questionnaire tool was performed
and determined the user's satisfaction level by using a sample survey. 1118
graduated students were subjected to this experiment. The following main
results were appeared:<

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Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Calculation of Coefficients of Cassegrain Telescope Mirrors
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In the present work, a program for calculating the coefficients of the Aplanatic Cassegrain Telescope (ACT) system, free from the effects of spherical and coma aberrations, were constructed. In addition, the two-mirrors of the optical system, as aspherical surfaces, were adopted. This means, that the two-equations of the mirrors are assumed to be polynomial function of five even terms only. The numerical method, least-squares curve fitting method to calculate the two-mirror coefficients system, was adopted. For choosing the values and ratios that give the best results, Rayleigh Criterion (Rayleigh Limit), for purpose of comparison and preference, was adopted.

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Crossref
Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Preparation Of Ferrocene Derivatives Of Niobium IV
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This study included the preparation of the dihalogens -1,3 metalla-2[3] ferrocenophanes
like Cp2NbS2Fc,(tBuCp)2NbS2Fc,Cp2NbSe2Fc and (tBuCp)2NbSe2Fe where (Fc=ferrocence)
These complexes has been prepared from the reaction of (R)2 NbCl2 with FCLiM2 ,
where(R=Cp,tBuCp) (M = S,Se) under refluxing in toluene,the reaction was carried under
Argon atmosphere .
These complexes were characterized by elemental microanalysis ,Masse spectra scopy,
nuclear magnetic resonance (
1
HNMR) and melting points .

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Publication Date
Wed Dec 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Evaluation of Mechanical Properties of Particulate Composites
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A series of experiments have been taken out to test the validity of the effect of Aluminum hydrate on its interaction with Aluminum during sintering of aluminum metal matrix. The approach has been shown to be valid and several compositions have been fabricated. The alumina hydrate particle size and the amount of alumina hydrate in the composites are also shown to have an influence on the extent of densification.

The densities for all sintered specimens were measured. It was found that density increases as compaction pressure increases, the density decreases as particles size increases. At 400 MPa there is an optimum particles size which is (90-125) µm to reach maximum density and the density decreases as volume fraction increase

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