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Study the Dissociation Enthalpies for R134a Clathrate Hydrate in Binary and Ternary Systems
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In the present work the clathrate hydrate dissociation enthalpies of refrigerant R134a+ water system, and R134a + water + salt system were determined. The heat of dissociation of three types of aqueous salts solutions of NaCl, KBr and NaF at three concentrations (0.09, 0.17and 0.26) mol·kg−1 for each salt type, were enthalpy measured. The Clapeyron equation was used tocalculate heat of dissociation of experimental data for binary and ternary system.In order to find the effect of compressibility factor on heat dissociation enthalpy, the study was conducted by using equation of state proposed by Peng and Robinson Stryjek-Vera (PRSV). The obtained results of dissociation enthalpy for binary system were (143.8) kJ.mol-1 without gas compressibility factor (z) and (136.08) kJ.mol-1 with z where the variation between two values was (5.3%). For ternary system (R134a+ water +NaCl) at three concentrations of this salt, the calculated values were in the range of (146.7 - 154.1) kJ.mol-1without z and (138.02-145.14) kJ.mol-1with z where the variation rang between two values was (5.8-5.7) %. The other two types of salts given similar results within (0.886 - 0.129) % deviation rang about NaCl results without z and (0.818-0.149) % deviation rang with z values.

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Study of Fatigue Fractography of Mild Steel Used in Automotive Industry
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Fatigue failure is almost considered as the predominant problem affecting automotive parts under dynamic loading condition. Thus, more understanding of crack behavior during fatigue can strongly help in finding the proper mechanism to avoid the final fracture and extent the service life of components. The main goal of this paper is to study the fracture behavior of low carbon steel which is used mostly in automotive industry. For this purpose, the fractography of samples subjected to high and low stress levels in fatigue test then was evaluated and analyzed. Hardness and tensile tests were carried out to determine the properties of used steel. Also, the samples were characterized by microstructure test and XRD analysis to examine the con

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Publication Date
Sun Jan 05 2014
Journal Name
Journal Of Educational And Psychological Researches
Unemployment & its Problems Between Theory & Applying Field Study in Baghdad City
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The unemployment is considered from the most danger problems that our society face them in current time & in the near future , because it makes prodigality for element of human being , particularly age of youth who have ability to work & producing , that resulted in negative effects forecast to dire consequences social and economical dangers . In the same time as will be stated in our explanation in the following in our research , because the unemployment has ability to help to prepare good environment to grow crime , actions of violence that mostly are main cause to decrease living level of majority of citizens & in increasing numbers who became under poverty , the unemployment is economical problem as it is psycholo

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Publication Date
Mon Jun 01 2009
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Used Approaches In Formulating Accounting Standards in Iraq & Their Develop Importance: filed Study
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This research aims to show the most important approaches applicable in forming the accounting standards , the  importance approaches used to formulate local accounting standards & the  need to cancel or develop the unified accounting system in Iraq besides activate the local auditing & accounting standards council to issue accounting standards able to save the relevance & Reliable accounting information that serve the decisions of stockholders and others of stakeholders in the incorporate companies , especially the companies listed in the Iraq securities exchange , So this study based partially on analyzing the questionnaire form which has been designed to inquiry the specialists and experts opinion about the accoun

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Publication Date
Sun Sep 30 2012
Journal Name
College Of Islamic Sciences
Surat Al-Qaria: a linguistic study
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Praise be to God, Lord of the worlds, and the best of prayers, and extradition was made to our master Muhammad and his whole family and companions:
And after:
Surat Al-Qariah is from the royal fence, which is in the thirtieth part of the Noble Qur’an. The commentators differed on the number of verses, and the reason for its naming. This surah talked about the conditions of people on the Day of Resurrection, and about how people were removed from their graves, all of which I spoke about in the preamble.
The research is divided into six topics: the first topic dealt with strange terms, while the second topic dealt with the most important audio issues mentioned in the surah, namely (slurring, advertising, substitution, and silenc

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Publication Date
Fri Oct 19 2018
Journal Name
Journal Of Economics And Administrative Sciences
Big Data Approch to Enhance Organizational Ambidexterity An Exploratory Study of a Sample of Managers at ASIA Cell For Mobile Telecommunication Company in Iraq
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               The research aimed at measuring the compatibility of Big date with the organizational Ambidexterity dimensions of the Asia cell  Mobile telecommunications company in Iraq in order to determine the possibility of adoption of Big data Triple as a approach to achieve organizational Ambidexterity.

The study adopted the descriptive analytical approach to collect and analyze the data collected by the questionnaire tool developed on the Likert scale After  a comprehensive review of the literature related to the two basic study dimensions, the data has been subjected to many statistical treatments in accordance with res

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Prepare a plan for the Total Productive Maintenance in the light of the concurrent engineering A Field Study in AL-Askandria General Company Machanical Industries and AL-Musaib Electric Power Station
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           Strives Total Productive Maintenance  to increase the overall effectiveness of the equipment through the early involvement in the design and manufacture of equipment productivity. It also operates in an environment of simultaneous engineering work on the synchronization of activities to take advantage of early information by maintenance engineers, design, operation, and that helps to reduce the faults and facilitate future maintenance tasks.

    Has adopted a search in the theoretical concept of the total maintenance productivity and concurrent engineering activities carried out during which the conjunction a

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Publication Date
Sat Nov 11 2023
Journal Name
Journal Of Dental Research, Dental Clinics, Dental Prospects
Investigating the effect of Er,Cr:YSGG laser agitation of sodium hypochlorite on the removal of mature biofilm in the complex root canal systems using atomic force microscopy
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Background. Endodontic infections caused by remaining biofilm following disinfection with chemical fluids encourage secondary bacterial infection; hence, employing laser pulses to activate the fluids is advised to improve microbial biofilm clearance. This study investigated the performance of Er,Cr:YSGG laser in photon-induced photoacoustic streaming (PIPS) agitation of 5.25% sodium hypochlorite (NaOCl) to enhance the removal of mature Enterococcus faecalis (E. faecalis) biofilms in complex root canal systems. Methods. The mesial roots of the lower first and second molars were separated and inoculated with E. faecalis bacteria for 30 days. The roots were irrigated with 5.25% NaOCl, some of them were agitated with passive ultrasonic

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Publication Date
Sat Sep 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of initial credit ratingAnnouncement of bonds on stock prices: An analytical study in the Abu Dhabi Securities Market
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The purpose of the research is to investigate the response of stock prices of companies that issued debt instruments (bonds) listed on the Abu Dhabi Securities Exchange for information content from the Moody's first credit rating announcements for the period 1 January 2005 - 30 May 2017. The study methodology was used to verify the existence of this response by the market and the Market efficiency of the Semi-strong shape.  The research focused on testing the impact of the initial announcement.The research showed that there is an influential information content to announce credit ratings in stock prices, with different responses between negative and positive. It was also found that the industrial sectors sample research separately d

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Study of Doppler broadening Compton scattering and cross section determination for the elements Fe, Zn, Ag, Au and Hg
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To assess the contribution of Doppler broadening and examine the
Compton profile, the Compton energy absorption cross sections are
measured and calculated using formulas based on a relativistic
impulse approximation. The Compton energy-absorption cross
sections are evaluated for different elements (Fe, Zn, Ag, Au and Hg)
and for a photon energy range (1 - 100 keV). With using these crosssections,
the Compton component of the mass–energy absorption
coefficient was derived, where the electron momentum prior to the
scattering event caused a Doppler broadening of the Compton line.
Also, the momentum resolution function was evaluated in terms of
incident and scattered photon energy and scattering angle. The res

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Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Languages (jcl)
Politeness: A Socio- Pragmatic Study
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The most influential theory of ‘Politeness’ was formulated in 1978 and revised in 1987 by Brown and Levinson. ‘Politeness’, which represents the interlocutors’ desire to be pleasant to each other through a positive manner of addressing, was claimed to be a universal phenomenon. The gist of the theory is the intention to mitigate ‘Face’ threats carried by certain ‘Face’ threatening acts towards others.

            ‘Politeness Theory’ is based on the concept that interlocutors have ‘Face’ (i.e., self and public – image) which they consciously project, try to protect and to preserve. The theory holds that various politeness strategies are used to prot

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