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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
Tue Jun 15 2021
Journal Name
Al-academy
The semiotic of the Islamic blazon - a related analytical study between the Islamic blazon and its publicity message: رغده بنت فيصل بن خضر الدعواني
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This study discusses the semiotic of the Islamic blazon - a related analytical study between the Islamic blazon and its visual publicity message. The aim of the current study is to explore the related relationship between the Islamic blazon and its visual publicity message. The sample is contained Five of Islamic blazon in the Mamelukes period which is between 1250 to 1517. The methodology is descriptive-analytical, and the result is that there is a clear relation between the Islamic blazon with its visual publicity message. This study's recommendation is to go towards analyzing the meanings of the cultural legacies of the Islamic civilization, and researching the implicit meanings accompanying these features leads to a deeper understand

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Publication Date
Fri May 10 2019
Journal Name
Research Journal Of Chemistry And Environment
Solid Phase Extraction of Theophylline in Aqueous Solutions by Modified Magnetic Iron Oxide Nanoparticles as an Extractor Material and Spectrophotometry Technique for the Determination
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new, simple and fast solid-phase extraction method for separation and preconcentration of trace theophylline in aqueous solutions was developed using magnetite nanoparticles (MIONPs) coated with aluminium oxide (AMIONPs) and modified with palmitate (P) as an extractor (P@AMIONPs). It has shown that the developed method has a fast absorbent rate of the theophylline at room temperature. The parameters that affect the absorbent of theophylline in the aqueous solutions have been investigated such as the amount of magnetite nanoparticle, pH, standing time and the volume, concentration of desorption solution. The linear range, limit of quantification (LOQ) and limit of detection (LOD) for the determination of theophylline were 0.05-2.450 μg mL-

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
Designand Implementation of New DES64X and DES128X on 32, 64 Bit Operating System Environments
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In this paper, a description of a design for new DES block cipher, namely DES64X and DES128X. The goals of this design, a part of its security level, are large implementation flexibility on various operating systems as well as high performances. The high level structure is based on the principle of DES and Feistel schema, and proposes the design of an efficient key-schedule algorithm which will output pseudorandomsequences of subkeys. The main goal is to reach the highest possible flexibility, in terms of round numbers, key size, and block size. A comparison of the proposed systems on 32-bit, 64-bit operating system, using 32-bit and 64-bit Java Virtual Machine (JVM), showed that the latter has much better performance than the former.

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Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Critical Success factors of Strategic Information system and it's relation with Strategic Decisions Effectiveness
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The organization uses many techniques and methods to ensure that they will succeed and adapted with velocity change in the internal and external environment by decision taking, especially strategic decisions.

Strategic decisions are very important for organization success because it can predict the future and deal with uncertainty, in this circumstances they need accurate and comprehensive information to make effective strategic decision.

To achieve that purpose it must owned successful Strategic Information System ( SIS ) and determined the critical success factors for this system ,which can assisted the worker to focus on the important activities to develop it.

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Publication Date
Mon Dec 01 2014
Journal Name
Advances In Engineering Software
System identification and control of robot manipulator based on fuzzy adaptive differential evolution algorithm
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Publication Date
Thu Dec 06 2018
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Formulation and Characterization of Bromocriptine Mesylate as Liquid Self-Nano Emulsifying Drug Delivery System
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Bromocriptine mesylate is a semisynthetic ergot alkaloid derivative with potent dopaminergic activity, used in the treatment of pituitary tumors, Parkinson's disease (PD), hyperprolactinaemia, neuroleptic malignant syndrome, and type 2 diabetes ,the oral bioavailability is  approximately 6%, therefore aim  its  prepare and evaluate bromocriptine mesylate  as liquid self nano emulsifying drug delivery system to enhance its solubility , dissolution and stability . Solubility study was made in different vehicles to select the best excipients for dissolving bromocriptine mesylate. Pseudo-ternary phase diagrams were constructed at 1:1, 2:1, 3:1 and 4:1 ratios of surfactant and co-surfactant, four formulations were pre

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Publication Date
Tue Apr 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
The viral marketing ( Its orgins, understandable, his campaing (stages, measured
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The concept of viral marketing is a modern concepts in the field of marketing studies and research in marketing functions, by relying on the notion of the spoken word and the written word, it is worth mentioning the lack of local research on viral marketing, research, analysis, and application and significantly encouraged interest in this topic by addressing basic concepts stand on its first seeds with focus theoretically on the viral marketing campaign planning across a field research adoption questionnaire prepared for this purpose had been distributed to a sample on a random sample of students of the Business Administration Department / College of administration and economics / University of Baghdad of 56 students and using the adequa

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Publication Date
Sun Mar 01 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Asset Utilization Efficiency and its effect on the sustainable Stockholder’s Wealth: Apply Study of Iraqi Companies listed on the Iraqi Stock Exchange
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The research discusses one of the most critical issues of corporate finance which is related to asset utilization efficiency. Researchers used internal growth rate as independent variable (Proxy of asset utilization efficiency) and sustainable growth rate-dependent variable (proxy of stockholders wealth). According to these two variables, researchers formulate major hypotheses (There is no significant effect of internal growth rate on sustainable growth rate), as well as two sub-hypotheses, examine the components of major variables. Sample of Iraqi industrial companies which listed in the Iraqi stock exchange selected to test and examine main hypotheses. Result of simple and multiple regressions explain there is a significant effect of i

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Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Agricultural And Statistical Sciences
EFFICACY ASSESSMENT OF BLACK PEPPER AND CLOVE EXTRACTS AGAINST SUNFLOWER SEEDS BLACK ROT DISEASE CAUSED BY ASPERGILLUS SPP.
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Publication Date
Sat Jan 01 2022
Journal Name
Revista Electronica De Veterinaria
The Molecular Identification of Pathogenic E. coli Isolated from Raw Cow Milk and Assessment Their Anti-susceptibility to Medical Plants at Al-Najaf city/ Iraq
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Background: Toxin-producing Shiga Escherichia coli has been identified as a new foodborne pathogen that poses a significant health risk to humans. Shiga toxin-producing Escherichia coli can be found in raw cow milk and its derivatives. A small number of Escherichia coli strains that produce shiga toxin are pathogenic. Aim of study: The study aimed to see if there were any virulence genes in 50 milk samples that were typical of Entero-haemorrhagic E. coli and evaluate the Myrtus communis effects on these bacteria. Materials and Method: Milk samples were used to isolate E. coli bacteria (n= 27), biochemically analyzed, and genetically screened for virulence genes using a multiplex (PCR). The hydro-alcoholic extraction of Myrtus communis leave

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