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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
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Knowledge of marketing and its impact on the performance of the company for the distribution of oil products –an exploratory study of the views of asample in the general company for oil products distribution/ Distribution Authority, Baghdad
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This study seeks to address the impact of marketing knowledge dimensions (product, price, promotion, distribution) on the organizational performance in relation to a number of variables which are (efficiency, effectiveness, market share, customer satisfaction), and seeks to reveal the role of marketing knowledge in organizational performance.

In order to achieve the objective of the study the researcher has adopted a hypothetical model that reflects the logical relationships between the variables of the study. In order to reveal the nature of these relationships, several hypotheses have been presented as tentative solutions and this study seeks to verify the validity of these hypotheses.

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Publication Date
Thu Jan 12 2023
Journal Name
Journal Of The Saudi Society Of Agricultural Sciences
Effect of planting density, foliar spraying and overlapping system on the growth and productivity using soilless culture system
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Publication Date
Sat Oct 28 2023
Journal Name
Baghdad Science Journal
Antibiotic Resistance of Staphylococcus Sp. Isolated from Air, Surface, Food and Clinical samples Collected from Baghdad Hospital
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Staphylococcus Sp.is the most common type of bacteria found in contamination place, we design this
study to compare the contamination accident between two hospitals in Baghdad.One of them isthe Burns
Specialist Hospital in the Medical CityinRusafa and another one is Al-Karama Hospital in Karkh. The
samples were collected fromOperativeWard No1 (OW1), Operative Ward No2 (OW2), Consulting Pharmacy
(CP), Emergency Room (ER), Reception Room (RR), Women's Ward (WW) and Men's Ward (MW).The
samples were taken from inside each clinical unit, surfaces, food, and air. The results showed that the
number of samples containing Staphylococcus sp. bacteria is 81, including 45 belonging to Al-Karama Burns
Ward Ho

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Publication Date
Sat Dec 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Work to Study the Behavior of Proppant Inside the Hydraulic Fractures and the Plugging Time
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Experiments were conducted to study the behavior of the solid particles (proppant) inside the hydraulic fracture during the formation stimulation, and study the effect of the proppant concentration on the hydraulic fracturing process, which lead to bridge and screen-out conditions inside the fractures across the fracture width that restricts fracturing fluid to flow into the hydraulic fracture. The research also studies the effect of the ratio between the fracture size and the average particles diameter “proppant", on fracture bridging. In this study two ratios were considered β= 2 and 3 ,where β=Dt / Dp where: Dt= hydraulic fracture size (width) and Dp=Average particles diameter.

This work pr

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Publication Date
Tue Dec 16 2008
Journal Name
Journal Of Planner And Development
The system of urban stability in the Kurdistan Region of Iraq
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The developing countries can be distinguished by spatial disparities and by this a wide gap between urban and rural settlements were produced as well as the appearance of primate cities. The effect of spatial development as a dynamic and continuous process can be perceived in the state of population distribution inside settlements inter and intra regions as well as the hierarchy of urban settlements according to time series. The research proved that the improvement judgment of the structure of the urban system using Gene factor is not accurate because it cannot be accounted for the internal components of the system which make a contrariety between the whole judgment (country) and partial components (Provinces including Sulaimaniy

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
The Role of inherited occupations in cohesion of the family system
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This study aims to study the inherited occupations which are considered to be a cultural, civilized and social legacy that effected by the Prevailing social and economic circumstances in the Iraqi society .
The study aimed to achieve several goals, including:
Identify the relationship between the urbanization and inherited occupations in the old city Al-Karkh.
Identify the relationship between the ecological construction and inherited occupations in the old city Al-Karkh.
Recognize the factors and motives inherited occupations in the study area .Identify the role of inherited occupations in promoting opportunities cohesion of the family system in the study area.
The field of the study had concentrated on a sample of famili

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Publication Date
Fri Dec 01 2023
Journal Name
Political Sciences Journal
Impact of the Rising of China in Restructuring the International System
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It is no secret to everyone that the Arab individual suffers from poor self-awareness and political awareness, which made the state and the importance of its existence and preserving its institutions not among his interests, which made researchers wonder about the possibility of strengthening it and the extent of its impact on the future of building the contemporary Arab state. So, the study attempts to addressing the issue of community awareness and its impact on building the state through a clear intellectual vision that blended what is social and political to define the concept of community awareness and highlight its importance and role as a basic pillar in shaping and building modern Arab countries in the Arab world and ways to enha

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Publication Date
Mon Nov 01 2010
Journal Name
Iraqi Journal Of Physics
Streams and plasma parameters experimental studies in He-CO gas mixtures
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DC glow discharges were generated between a thin cylindrical anode and a flat cathode, streamers are thought to propagate by photo-ionization; the parameters of photo-ionization depend on the He: CO ratio. Therefore we study streamers in He ( 90%, 80% and 70% ) with (10%, 20% and 30%) CO respectively. The streamer diameter is essentially the change by increase for similar voltage and pressure in all He-CO mixtures.

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Publication Date
Mon Jan 01 2018
Journal Name
Indian Journal Of Public Health Research & Development
Environmental Assessment of the Quality of Water and the Hydrochemical Formula Used for Some Groundwater Wells in Karbala Governorate
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Publication Date
Sun Feb 22 2026
Journal Name
Al–bahith Al–a'alami
The Impact of Means of Communication on Electoral Behavior and its Relationship to the Political Disparity of the Family (A Field Study of an Audience of the University of Baghdad’s Students)
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Iraq has seen many changes at the social, economic and political levels. This led to cause many shifts in the structure of its society and imposed great challenges reflected in the behavior and awareness of that society in general and youth in particular.

Those changes made the Iraqi society undergoing the transformation of value and culture aspects formed a political awareness that caused cultural and political diversity within the family and society. A greater openness to the outside world caused by the communication revolution, as the world has witnessed during the past two decades, has helped in making that change. Iraq had its share of media and political openness, which were included after the US occupation in 2003. As a re

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