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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
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
Improvement of the surface hardness and wear resistant of low carbon steel using laser radiation
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Publication Date
Fri Nov 11 2022
Journal Name
International Journal Of Professional Business Review
Measuring the Level of Performance of Accounting Units and Their Impact on the Control Environment
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Purpose: The research aims to study the measurement of the performance of accounting units level of the research sample by using the Federal quality Model European (EFQM)   Design/methodology/approach: the (EFQM) which included seven dimensions "Leadership, Strategic Planning, External Focus, Information and Analysis, Faculty / Staff and Workplace Focus, Process Effectiveness & Outcomes and Achievements" And its effect on the Control Environment, which includes three dimensions: "Integrity, management philosophy and commitment to powers" . the sample is supervisory units of colleges affiliated with the University of Baghdad in Iraq, and a sample was chosen that included fifty-one individuals in the accounting departments.

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Publication Date
Fri Jun 01 2018
Journal Name
أ.م. حسين علي خضير بهاري
Symbolism of Jekor Village in the Poetry of the Iraqi Poet Badr Shakir as-Sayyab
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The paper aims at making the Russian reader acquainted with the Iraqi Poet Badr Shakir as-Sayyab, and showing the effect of the village and the city in his soul, the theme which is reflected in his poetry. Therefore, the researcher has translated the verses pertaining to this topic from Arabic into Russian so as to make the Russian reader know the important phases that talk about the village and city. The researcher has concluded that the theme of place, village and city has occupied a good portion of As-Sayyab's poetry, and that he (the poet) hated the city and expressed his wrath against it, because he viewed the city as embodiment of money and the degeneration of man. As opposed to this, As-Sayyab he loved being a farmer, and was

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Publication Date
Mon Sep 20 2021
Journal Name
Key Engineering Materials
The Effect of Quantum Confinement on Optical Properties of CdSe Quantum Dots at Room Temperature
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CdSe quantum dots possess a tuning energy gap which can control gap values according to the size of the quantum dots, this is made the material able to absorb the wavelengths within visible light. A simple model is provided for the absorption coefficient, optical properties, and optical constants for CdSe quantum dots from the size 10nm to 1nm with the range of visible region between (300-730) nm at room temperature. It turns out that there is an absorption threshold for each wavelength, CdSe quantum dots begin to absorb the visible spectrum of 1.4 nm at room temperature for a wavelength of 300 nm. It has been noted that; when the wavelength is increased, the absorption threshold also increases. This applies to the optical propertie

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Expectations of self-efficiency and its relation to life skills at teachers of secondary schools
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Research aims
1. Measuring expectations of self-efficiency at teachers of secondary schools.
2. Measuring biological skills at teachers of secondary schools.
3. There is no sole or gathering forecasting of forecasting expectations of self-efficiency , may forecasts about biological skills at teachers of secondary schools.
To fulfill aims of the research, the researcher managed measuring of expectations of self-efficiency according to point of view of Bandura for this concept in this research, arranging measure of biological skills according to view of global health, the researcher has made to investigate of truth , constant these two measurements, analyzing statistically their two paragraphs on a sample (460) teachers (males

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Publication Date
Mon Jun 22 2020
Journal Name
Baghdad Science Journal
Effects of Anthracene Doping Ratio and UV Irradiation Time on Photo-Fries Rearrangement of Polycarbonate
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Thin films of pure polycarbonate (PC) with anthracene doping PC films for different doping ratios (10, 20, 30, 40, 50 and 60 ml) were prepared by using a casting method. The influence of anthracene doping ratio on photo-fries rearrangement of polycarbonate was systematic investigated. Furthermore, pure PC and anthracene doping PC films were irradiated via UV light at a wavelength (254 nm) for different periods (5, 240, 288, and 360 hrs). The photo-fries rearrangement occurring in pure PC and anthracene doping PC films were monitored using UV and FTIR spectroscopies. The photo-fries rearrangement leads to scission the carbonate linkage and formation phenylsalicylate and dihydroxybenzophenes. The result of the UV spectrum confirms disappea

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Publication Date
Sun Jul 13 2025
Journal Name
Journal Of Physical Education
Analytical Study Of Performance Efficiency and Organizational Commitment of Iraqi Central Federation Athletics' Referees
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Publication Date
Sun Aug 30 2020
Journal Name
Turkish Journal Of Agriculture - Food Science And Technology
Determination of Operating Characteristics of 540 and 540E PTO Applications in Disc Type Silage Machines
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In this study, performance characteristics such as power take off (PTO) power consumption, fuel consumption, fuel consumption for the unit field-unit product were determined at different working speeds with two different PTO applications (540 and 540E) in a single row disc type silage machine. In particular, the 540E PTO application greatly reduces fuel consumption for unit work. The best results in terms of hourly fuel consumption were achieved in 540E PTO application and V1 working speed. When the field - product fuel consumption is evaluated, the best results were obtained with the 540E PTO application at the V3 working speed. When an evaluation is made considering all the parameters, it is concluded that the 540E PTO application will p

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Publication Date
Tue Aug 01 2023
Journal Name
Baghdad Science Journal
The Effect of Electrospinning Parameters on Morphological and Mechanical Properties of PAN-based Nanofibers Membrane
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The electrospun nanofibers membranes (ENMs) have gained great attention due to their superior performance. However, the low mechanical strength of ENMs, such as the rigidity and low strength, limits their applications in many aspects which need adequate strength, such as water filtration. This work investigates the impact of electrospinning parameters on the properties of ENMs fabricated from polyacrylonitrile (PAN) solved in N, N-Dimethylformamide (DMF). The studied electrospinning parameters were polymer concentration, solution flow rate, collector rotating speed, and the distance between the needle and collector. The fabricated ENMs were characterized using scanning electron microscopy (SEM) to understand the surface morphology and es

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Preparation and identification of oxidatin derivaties for Salts and acids of bile for medical uses
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The purified prepared compounds were identified through different methods of identification i.e, I.R, UV-vi^ble-spectroscopy in addition to (coloured tests) Calculation of the sum of OH groups. TLC techniques were also used to test the purity and the speed ofthe rate of flow (RF).

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