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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
Thu Jun 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Isotherms and Kinetics Study for Adsorption of Nitrogen from Air using Zeolite Li-LSX to Produce Medical Oxygen
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This research investigates the adsorption isotherm and adsorption kinetics of nitrogen from air using packed bed of Li-LSX zeolite to get medical oxygen. Experiments were carried out to estimate the produced oxygen purity under different operating conditions: input pressure of 0.5 – 2.5 bar, feed flow rate of air of 2 – 10 L.min-1 and packing height of 9-16 cm. The adsorption isotherm was studied at the best conditions of input pressure of 2.5 bar, the height of packing 16 cm, and flow rate 6 Lmin-1 at ambient temperature, at these conditions   the highest purity of oxygen by this system 73.15 vol % of outlet gas was produced. Langmuir isotherm was the best models representing the experimental data., and the m

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Publication Date
Sun Mar 03 2013
Journal Name
Baghdad Science Journal
Species of Centaurium Hill. in Iraq and its geographical distribution
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Comparative taxonomic study has been compeleted for the species of the. genus Centaurium Hill. of Iraq. So the morphological characters were studied comparatively for the first time form Iraqi materials. Stems, leaves ,infloresences and reproductive organs characters were a good taxonomic importance. Geographical distrtribution has been done for the species of the genus in addition to the environment information. The results were presented with schedules, tables, maps and micrographs. Taxonomic key for the species separation was also presented.

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Dietary Assessment for Meals of Nurseries Children in Baghdad City
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The objective of this study was to assess the nutritional status of childs of nurseries in Baghdad city so that an early detection of malnutrition cases could be carried out. The results revealed that the daily consumption of food calories, protein, fat and carbohydrate were 1180.5 calories, 27.2gm, 38gm and 180gm, respectively, which were less than the RDA values and the percentages of these nutrients supplied by the food intake were 90.8, 83.7, 87.3 and 90.3%, respectively. It was also demonstrated that the highest percentages of stunting, underweight and wasting, which amounted to 32, 22.7 and 1.5%, respectively, were among those childs who obtained inadequate calories, while the percentages of the forementioned malnutrition cases amon

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Publication Date
Sun Oct 29 2023
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessment of Premenstrual Syndrome among Working Women in Baghdad City
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Objectives: To assess the premenstrual syndrome among the working women in Baghdad City.
Methodology: A cross-sectional analytic study, using probability sampling cluster (multi-stage) sampling of
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designed and consisted of (4) parts, including demographic, reproductive, menstrual cycle characteristics, and
premeustmual syndrome symptoms. Content validity and reliability of the questionnaire were detemined by
conducting a pilot study. Descriptive and inferential statistical procedures were used to analyze the data.
Results: The results of the study revealed that the age of women ranged betwee

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Publication Date
Sat Sep 15 2018
Journal Name
Journal Of Baghdad College Of Dentistry
Assessment of Dental Caries among Internally Displaced Children in Baghdad
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Background: The internally displaced children are vulnerable groups have less access to dental services, worse oral health, and bear a disproportionate burden of oral diseases. Aim of the study: This study was conducted on group of internally displaced children living in Baghdad governorate camps to measure their dental caries prevalence and experience and find out the association between dental caries and the duration of displacement in camps. Subjects and methods: A sample of 1393 children were selected, 567 internally displaced children from camps in Baghdad governorate and 826 school children as control matching in age and gender. The age of children ranged from 5-12 years old. Oral examination was performed using WHO 2013 criteria, to

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Publication Date
Mon Apr 30 2012
Journal Name
Journal Of Planner And Development
RAPID LAND TENURE ASSESSMENT OF BAGHDAD CITY IN IRAQ 2010
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The purpose of this study is to describe the extent and nature of informal tenure practices in urban areas in Iraq, through undertaking a rapid assessment in Baghdad city. The UN-HABITAT 2008 publication Secure Land Rights for All discusses the importance of access and rights to land throughout the developing world. Secure land rights are critical to development and poverty reduction, and the greatest challenge in providing secure land rights are in urban areas, where overcrowding can lead to a number of informal tenure practices ranging from individually unregistered or unauthorised housing, to large informal settlements. Access to land is a fundamental basis for human shelter, food production, and other economic activity. Secur

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Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
Assessment of nuclear radiation pollution in uranium mining-impacted soil
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Activities associated with mining of uranium have generated significant quantities of waste materials containing uranium and other toxic metals. A qualitative and quantitative study was performed to assess the situation of nuclear pollution resulting from waste of drilling and exploration left on the surface layer of soil surrounding the abandoned uranium mine hole located in the southern of Najaf province in Iraq state. To measure the specific activity, twenty five surface soil samples were collected, prepared and analyzed by using gamma- ray spectrometer based on high counting efficiency NaI(Tl) scintillation detector. The results showed that the specific activities in Bq/kg are 37.31 to 1112.47 with mean of 268.16, 0.28 to 18.57 with

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Publication Date
Sat Dec 30 2023
Journal Name
Al-kindy College Medical Journal
Assessment of Serum Metalloendopeptidase level in Patients with Double Diabetes
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Background: Double diabetes is the term used to describe situations in which a patient exhibits characteristics that are a combination of type 1 and type 2 Diabetes Mellitus. Metalloendopeptidase or Neprilysin is membrane-bound metallopeptidase. It has a wide range of physiological function and a variety of substrates. It has a significant impact on the proteolytic functions of the kidney, cardiovascular health, immunological response, cell proliferation, and fetal development. It also has a preventative effect on the onset of type 2 diabetes, obesity, and cancer.

Objective: The study aims to assess the level of MEP in patients wi

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Publication Date
Mon Jan 29 2018
Journal Name
Environmental Earth Sciences
A preliminary assessment of the geochemical factors affecting groundwater and surface water quality around the rural communities in Al-Anbar, Western Desert of Iraq
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Publication Date
Wed Jun 20 2018
Journal Name
Al-academy
Simulation and its applications in contemporary graphic design
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   The simulation is the oldest theory in art, since it appeared in the Greek aesthetic thought of the philosopher Plato, as we find in many of the thinkers and philosophers over a wide period of time to reach our world today. Our fascination with art in general and design art in particular is due to the creativity and innovations of the artist through the simulation, as well as the peculiarities in this simulation, which give objects signs and signals that may have an echo that sometimes does not exist in their physical reality.

   The real representation of life and design construction, descriptions of the expression of each of them in the form of intellectual construction and the ideas of producti

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