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The Experimental Assessment of R134a and Its Lower GWP Alternative R1234yf in an Automobile Air Conditioning System
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Reducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplished for both refrigerants in almost the same working conditions and procedure with a range of ambient temperature varied from 26oC to 50oC. Parameters studied were ambient temperature, type of refrigerant in the system at compressor speed 1450 rpm, and internal thermal loads of passenger room. The performance characteristics of the system, including COP and cooling capacity, were studied by changing different parameters. The results show that COP of R134a is higher than R1234yf by 12.6%, while the refrigeration effect of R134a is higher than R1234yf by 25%. This shows that R1234yf is a suitable and good candidate for drop-in replacement of R134a in AACS.

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Publication Date
Sat Dec 28 2019
Journal Name
The Iraqi Journal Of Veterinary Medicine
Incidence of Canine Digestive System Tumours in Baghdad Province
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Tumours in pets occur naturally and are common in dogs as they are in humans. Tumours of the alimentary system have been reported in animals, although less frequently. Food patterns and specific diet components could have a big role in such tumour occurrence. Therefore, the aim of this study was to investigate the clinical signs and inspect the neoplasm lesions of the gastrointestinal (GI) tract grossly and histopathologically in dogs in Baghdad, Iraq, and to see whether pet diets had any tumourigenic effect. Throughout two years sixteen dogs were referred to Teaching Animal Hospital and private clinics at Baghdad city with masses in (GI) tract. Males and large size breeds were more likely to be affected with GI tumours. Half of the cases a

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Publication Date
Thu Dec 15 2022
Journal Name
Al-academy
Strategies of brain-based learning theory and its impact on the achievement of students of the Department of Art Education in Teaching Methods
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The aim of the current research is to reveal the effect of using brain-based learning theory strategies on the achievement of Art Education students in the subject of Teaching Methods. The experimental design with two equal experimental and control groups was used. The experimental design with two independent and equal groups was used, and the total of the research sample was (60) male and female students, (30) male and female students represented the experimental group, and (30) male and female students represented the control group. The researcher prepared the research tool represented by the cognitive achievement test consisting of (20) questions, and it was characterized by honesty and reliability, and the experiment lasted (6) weeks

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Publication Date
Tue Sep 17 2019
Journal Name
Journal Of The College Of Education For Women
The Architectural Heritage of Baghdad in Ibn Al-Faqih Hamadani's Book Baghdad the City of Peace And its impact on Sustainable Development
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This research shows the importance of Baghdad in the field of urban heritage and was demonstrated in the Ibn al-Fiqh al-Hamdani's book Baghdad the City of Peace in which he focused on many urban aspects and reviewing its historical importance by connecting them with modern events and the role they play in cultural and civilized construction which included: mosques, schools and markets etc. and the service providing institutions and other pillars of the Islamic cities through showing the development back then and its importance as an integral part of the urban and cultural heritage of the Islamic cities in general and Baghdad city in particular. 

In his book Baghdad the City of Peace, Ibn al-Faqih Hamadhaani

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Publication Date
Thu Jul 01 2021
Journal Name
Turkish Journal Of Physiotherapy And Rehabilitation
ORGANIZATIONAL CONFIDENCE AND ITS IMPACT ON THE DECENTRALIZED PERFORMANCE OF THOSE IN CHARGE OF MANAGING LOCAL CHAMPIONSHIPS FOR THE IRAQI ATHLETICS FEDERATION
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The aim of the research is to identify the level of both organizational trust and decentralized performance of those in charge of managing local championships for the Iraqi Athletics Federation, and to identify the effect of organizational trust in decentralized performance from their point of view. The descriptive approach was based on the method of relational relations on a sample of those in charge of managing local championships for the Iraqi Federation In athletics, represented by each of (coaches, referees, members, president and members of the administrative body of the central federation, and the president of members of sub-federations) for the sports season (2020/2021) of 260 individuals, all of them were intentionally chosen by (1

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Publication Date
Fri Mar 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Accounting achievement and its impact on the measurement of operational efficiency: Applied research in the company of refineries Center / Al-Doura refinery
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The issue of measurement of operational efficiency and productivity plays a major role in determining the weakness of the company, especially in relation to the productive processes, and thus starting to address these points and improve their performance. Hence the problem of research on how to determine the constraints in the production process, to identify weaknesses in the company. The research aims to clarify the role of throughput accounting in measuring the operational efficiency of the company in addition to clarify some of the constraints and causes behind them. The study concluded a set of conclusions, the most important of which is the availability of throughput accounting indicators that help in measuring operational efficienc

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Publication Date
Tue Jan 01 2008
Journal Name
University Of Baghdad
The use of remote sensing to study the reflection of the ground cover and its relationship to some soil characteristics in the Abi Gharib area
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Publication Date
Sun Oct 12 2025
Journal Name
Revista Iberoamericana De Psicología Del Ejercicio Y El Deporte, Issn 1886-8576, Vol. 17, Nº. 4, 2022, Págs. 165-167
Social-kinetic Cohesion and its Relationship to Goal Direction with its two Dimensions (Performance and Result) for Advanced Handball Players in Iraq
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Autorías: Muhammad Hamza Shihab, Nuha Mohsin Dhahi. Localización: Revista iberoamericana de psicología del ejercicio y el deporte. Nº. 4, 2022. Artículo de Revista en Dialnet.

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Publication Date
Thu Sep 03 2020
Journal Name
Dissertation
An Economic And Environmental Analysis of the most Factors Affecting of Sustainable Agricultural Development In Iraq Through The Period 2000 -2017
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Publication Date
Sun Oct 12 2025
Journal Name
Journal Of Baghdad College Of Dentistry
The Influence of Different Fabrication Techniques and Preparation Designs on the Marginal Adaptation of Ceramic Veneers (An In vitro Comparative Study)
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Background: Ceramic veneers represent the treatment of choice in minimally invasive esthetic dentistry; one of the critical factors in their long term success is marginal adaptation. The aim of the present study is to evaluate the marginal gap of ceramic veneers by using two different fabrication techniques and two different designs of preparation. Material and methods: A typodont maxillary central incisor used in the preparation from which metal dies were fabricated, which were in turn used to make forty stone dies. The dies divided into four experimental groups, each group had ten samples: A1: prepared with butt-joint incisal reduction and restored with IPS e.max CAD, A2: prepared with overlapped incisal reduction and restored with IPS e.

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Publication Date
Sat Oct 01 2022
Journal Name
Al–bahith Al–a'alami
Employing Statistical Analysis in Public Relations Researches: (An Analytical Study of the Theses and Dissertations of Public Relations for the Period from 2005 to 2012)
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Public relations are amongst the social sciences that rely on scientific methods in achieving new knowledge or resolving existing problems by means of its scientific researches that are often applied and require a classification in terms of their results’ analysis. It also requires subtle statistical processes whether in constructing their material or in analyzing and interpreting their results.

This research seeks to identify the relation between public relations and statistics, and the significance a researcher or practitioner in the domain of public relations should assign to statistics being one of the important criteria in identifying the accuracy and object

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