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Exergy Analysis of a Domestic Refrigerator
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An energy and exergy thermodynamic analysis using EES program was done for a domestic refrigerator working with R-134a using vapor compression refrigeration cycle. The analysis deals with the system component, i.e. compressor, condenser, evaporator and the expansion device. The analysis depends on the entropy generation minimization approach to improve the refrigerator performance by exploring the optimum design points. These design points were derived from three different theories governing the entropy generation minimization using exergy analyzing method. These theories were first applied to find the optimum balance between the hot inner condenser area and the cold inner evaporator area of the refrigerator and between its hot and cold thermal conductances. Nine types of condensers were used according to its internal surface area and thermal conductance, in order to reach the minimum entropy generation in the refrigerator. The results showed that the compressor has the lowest exergy efficiency of 25%. The expansion device was the second component after the compressor with exergy efficiency of 92%, followed by the condenser with an efficiency of 93%. The evaporator was found to have an exergy efficiency of 98 %. The experimental tests were repeated for the nine condensers sizes with three different ambient temperatures 25℃, 30℃ and 35℃.  The exergy analysis showed that the design of the refrigerator mainly depends on thermal conductance calculations rather than the surface inner area estimation.

 

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Publication Date
Wed Mar 01 2023
Journal Name
Baghdad Science Journal
New Structures of Continuous Functions
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         Continuous functions are novel concepts in topology. Many topologists contributed to the theory of continuous functions in topology. The present authors continued the study on continuous functions by utilizing the concept of gpα-closed sets in topology and introduced the concepts of weakly, subweakly and almost continuous functions. Further, the properties of these functions are established.

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Publication Date
Wed Jan 01 2020
Journal Name
Pakistan Journal Of Agricultural Sciences
Pakistan Journal of Agricultural Sciences
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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
SIMULATION OF FLIGHT THROUGH GUST
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A flight simulation programme has been developed on a personal computer using Microsoft
FORTRAN to simulate flight trajectories of a light aircraft by using Six-Degree-of-Freedom
equation of motion. The simulation has been made realistic through pre-programmed the input to
the control surfaces, atmospheric gust during the flight mode. The programme plays an important
role in the evaluation and validation of the aircraft design process. A light aircraft (Cessna 182T)
has been tested through free flight, gliding flight, flight with gust. The results show good trend and
show that the programme could be dependent as a realistic flight test programme.

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Publication Date
Thu Jan 30 2014
Journal Name
Al-kindy College Medical Journal
Management of Hypertension in Elderly
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Background:The document on hypertension in the elderly promoted by the American college of cardiology and the American heart association (ACCF/AHA) was written with the intent to be a complete reference at the time of publication on the topic of managing hypertension in the elderly. More recently, the European society of hypertension (ESH) and the European society of cardiology (ESC) issued the 2013 ESH/ESC Guidelines for the management of arterial hypertension, followed by The 2014 Canadian Hypertension Education Program (CHPE), and the Eighth Report of the Joint National Committee (JNC8), all of which has endorsed specific recommendations for the management of elderly hypertensive patients.

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Publication Date
Sun Sep 30 2001
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Hydrotreating of Sharki Baghdad Residue
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Publication Date
Thu Apr 11 2019
Journal Name
Political Sciences Journal
Scientific Activities College of branches
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Scientific Activities College of branches

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Publication Date
Wed May 01 2019
Journal Name
Journal Of Engineering
Thixotropic Hardening of Fao Clay
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Fao region is characterized by weak soft silty clay to clayey silt thick layer which extends to a depth of about 20 m. The construction of some structures on such soils may needs piles. During the installation of driven piles, the soil geotechnical properties are exposed to significant changes result due to shearing under large shear strains. These changes significantly decrease the shear strength of the virgin soil due to the destruction of soil structure caused by remolding. The degradation of shear strength is usually followed by strength regaining which is called “Thixotropy”. In this study, the thixotropic effect on Fao clay was investigated. Many disturbed and undisturbed soil samples were brought from Fao regi

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
Sponsorship of widows in Islam
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The research addressed the problem of widows that increased recently enormously. The researcher also referred to the perspective of Islam that gave a significant attention for both widows and orphans as powerless groups. Some straightforward example were presented to reflect the actual difficulties that encounter these groups as well as the author proposed number of appropriate ways that mitigate their psychological and physical sufferings such as: the provision of convenience jobs, and the legislation of rule that save their rights. Moreover, the researcher addressed the importance of marrying widows and what these challenges that encounter polygamy in Arab societies, the advantages and disadvantages of polygamy, and discussing all the

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Publication Date
Tue Jun 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Kinetic Study of Esterification Reaction
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The Esterification kinetics of acetic acid with ethanol in the presence of sulfuric acid as a homogenous catalyst was studied with isothermal batch experiments at 50-60°C and at a different molar ratio of ethanol to acetic acid [EtOH/Ac]. Investigation of kinetics of the reaction indicated that the low of [EtOH/Ac] molar ratio is favored for esterification reaction, this is due to the reaction is catalyzed by acid. The maximum conversion, approximately 80% was obtained at 60°C for molar ratio of 10 EtOH/Ac. It was found that increasing temperature of the reaction, increases the rate constant and conversion at a certain mole ratio, that is due to the esterification is exothermic. Activity coefficients were calculated using UNIFAC progra

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Publication Date
Sun Mar 19 2023
Journal Name
Journal Of Educational And Psychological Researches
Communicative Competence of University Students
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Abstract

The current research aims to identify the communicative competence of university students, to identify the levels of communicative competence among university students and which of these levels are more common, and to identify the significance of differences in communicative competence among university students according to the variables of gender and specialization. The study population consisted of (782) male and female students, as the statistical analysis sample was limited to (400) male and female students to extract the psychometric properties of the current research tool. The study sample included (382) male and female students at the University of Baghdad who were chosen by the stratified random

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