Preferred Language
Articles
/
joe-668
The Experimental Assessment of R134a and Its Lower GWP Alternative R1234yf in an Automobile Air Conditioning System

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.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Sep 11 2018
Journal Name
Iraqi Journal Of Physics
Preparation and study the structure of pure and impure barium titanate with Mg2+ ion

Pure and doped barium titanate with Mg2+ ion at two molar ratios x= (5%, 10%) mol. has been synthesized by solid state reaction technique. The powders sintered at two temperatures (1000 °C and 1400 °C). An XRD technique was used in order to study the crystal structure of pure and doped barium titanate, which confirmed the formation of the tetragonal phase of BaTiO3, and then calculate the lattice parameters of pure and doped barium titanate, the addition of magnesium ion Mg2+ can lead to decreases lattice parameters.

Crossref
View Publication Preview PDF
Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Relationship and impact of the Analysis and evaluation jobs with employees performance : Survey study

        The aim the research that definition on the impact a lot of Analysis and evaluation jobs impact in support the employees performance the property that are Analysis and evaluation jobs is one of the jobs however of the human resource management on organization and the impact footpace big on the chractericties and performance of the people and the impact that success of the organization , And here problem stool of the research in the omission the role for the Analysis and evaluation jobs impact in support the employees performance from the upward management in the organization , Polls were adopted as tools for obtaining data and the Depart

... Show More
Crossref
View Publication Preview PDF
Publication Date
Sat Jun 06 2020
Journal Name
Journal Of The College Of Education For Women
Conformity and nonconformity and their relation to the emotional balance of high school students

 Complex and complex psychological processes are complexand are the result of convergence, convergence and interaction between variables, including the subject of mediation or group or individual and psychological processes involved in the variance, including - personal knowledge and emotional tone (Osman, 1987, p. 8 ). An emotionally balanced individual has the ability to endure and delay meeting needs and has the ability to endure as much as possible. Of the emotional balance of the individual is characterized by emotional stability, show some signs of emotional agitation toward any kind of opposition, anger and realism in self-life and discipline (Swift, 1996, p. 44) Van, et al. , Indicates that people with low emotional balance,

... Show More
View Publication Preview PDF
Publication Date
Tue Jun 30 2015
Journal Name
College Of Islamic Sciences
Structural and contextual dimensions of the coming   Intervals Between that diluted and her experience

In the name of of Allah the Merciful
Praise be to Allah, Lord of the Worlds, and prayers and peace be upon the Seal of the Prophets and Messengers. The envoy is a mercy to the worlds Muhammad Sadiq Al - Amin, and to the pure and good companions of the Tayyibites.
The formula of the morphological formulas, which have diverged from other meanings, whether lexicon or contextual and what this formula contains many meanings (effective source) and (effective in the sense of effective) and (effective sense reactor) and (effective sense) and ( (F) in the sense of a similar character) and ((the name of the) (collect). This was dealt with in the formula in Surat al-Nisaa a gramophone study. As mentioned in the study of the morphological subj

... Show More
View Publication Preview PDF
Publication Date
Wed Aug 30 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Some Immunological and Cytological Aspects .of The Breast and Uterus Can.cer Patients After Radiotherapy

The- role of radiotherapy in immunological and  cytological function of  patients.  with  carcino.ma  of  breast 'tDd   uterus  were  investigared: Using n:>sette forming T lYJi'lphl)Cytes, white  blood  cell's and lymphocytes  count  and  distributiQn  of  micronuclei  as  parameters . After  irradiation . the number  of  peripheral   blood  lymphocytes and vvhite blood  cells  was  reduced  . The  percentage of ro:sette Jorming  T

ly mphocytes   were· alsu  decreased   while  NBT  percentage  Of poly

morpho  nudcocyte

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 11 2018
Journal Name
Iraqi Journal Of Physics
Preparation and study the structure of pure and impure barium titanate with Mg2+ ion

Pure and doped barium titanate with Mg2+ ion at two molar ratios x= (5%, 10%) mol. has been synthesized by solid state reaction technique. The powders sintered at two temperatures (1000 °C and 1400 °C). An XRD technique was used in order to study the crystal structure of pure and doped barium titanate, which confirmed the formation of the tetragonal phase of BaTiO3, and then calculate the lattice parameters of pure and doped barium titanate, the addition of magnesium ion Mg2+ can lead to decreases lattice parameters.

Crossref
View Publication Preview PDF
Publication Date
Sat Jun 25 2022
Journal Name
International Journal Of Drug Delivery Technology
Synthesis and Evaluating the Antimicrobial Activities of Various Adducts Prepared from Isatins and Proline

characteristic tissues and cells, exerting their pharmacological aspects and alleviating a lot of diseased processes. Accordingly, this research is about introducing some isatins to be nucleophilically attacked at C3 forming products of azomethine ylide functionality. These iminium compounds were made by allowing certain isatins to be reacted with the secondary amino acid, proline, at acetic acid and methanol medium and then collected after purification to be identified with total Leukocyte count (TLC) and melting point. The structural characterization was performed by fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), and community health nursing (CHN) analysis. The microbiological evaluatio

... Show More
Scopus Crossref
View Publication
Publication Date
Tue Feb 01 2022
Journal Name
Baghdad Science Journal
Flow Injection Analysis with Turbidity Detection for the Quantitative Determination of Mebeverine Hydrochloride in Pharmaceutical Formulations

The main objective of this paper is to develop and validate flow injection method, a precise, accurate, simple, economic, low cost and specific turbidimetric method for the quantitative determination of mebeverine hydrochloride (MbH) in pharmaceutical preparations.  A homemade NAG Dual & Solo (0-180º) analyser which contains two identical detections units (cell 1 and 2) was applied for turbidity measurements. The developed method was optimized for different chemical and physical parameters such as perception reagent concentrations, aqueous salts solutions, flow rate, the intensity of the sources light, sample volume, mixing coil and purge time. The correlation coefficients (r) of the developed method were 0.9980 and 0.9986 for cell

... Show More
Scopus (15)
Crossref (9)
Scopus Clarivate Crossref
View Publication Preview PDF
Publication Date
Tue Aug 03 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Structural Equation Modeling for Tourist Attraction Factors in Asir Region by Using Factor Analysis in the Light of Vision of kingdom of Saudi Arabia (KSA) 2030

The research aimed to modeling a structural equation for tourist attraction factors in Asir Region. The research population is the people in the region, and a simple random sample of 332 individuals were selected. The factor analysis as a reliable statistical method in this phenomenon was used to modeling and testing the structural model of tourism, and analyzing the data by using SPSS and AMOS statistical computerized programs. The study reached a number of results, the most important of them are: the tourist attraction factors model consists of five factors which explain 69.3% of the total variance. These are: the provision of tourist services, social and historic factors, mountains, weather and natural parks. And the differenc

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 24 2022
Journal Name
Journal Of Legal Sciences
Legal Controls for Transfer and Transplantation of Human Organs and Tissues in Sultanate of Oman- Reality and Hope

This study ideals with the Omani legal regulations of transferring and transplanting human organs and tissues in light of the Minister of Health decree No. 179 on the year 2018. As the last update, article 27 in 2019 has prohibited conducting such operations unless permission from the Minister of Health is obtained. In the absence of a further law update until the completion of writing the research, we intend to analyze and study some of the current provisions for the transfer and transplantation of human organs and tissues, compared to the legislative trends of some related laws. To achieve this, we divided the study into three sections; the first section introduces the historical development of the legislator criminal policy in regulat

... Show More
View Publication Preview PDF