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Experimental Study on Double-Pass Solar Air Heater with and without using Phase Change Material
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In this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant air mass flow rate of (0.0375 kg/sec). The parameters that affect the thermal performance of the SAH with and without the PCMs presented by solar radiation, the difference in air temperature, outlet air temperature, instantaneous thermal efficiency, and daily efficiency are evaluated. The experimental results show that when using the PCM, the temperature of the outlet air was enhanced and increased over the ambient temperature by (1.5 - 6.5 C) after sunset for 5 hours period. It was found that the instantaneous thermal efficiency of the heater using thermal storage exceeds 100% after sunset, this is due to a large amount of heat stored in the paraffin wax that has been released during the discharge process. Also, it was found that the daily efficiency of the double pass SAH integrated with and without thermal energy storage unit was (56, 47%) respectively.

 

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Publication Date
Fri Mar 25 2022
Journal Name
Nasaq Journal
A Linguistic Study of Paronomasia (Al-Jinās ) in Arabic and English
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Paronomasia is a recognized rhetorical device by which poets could play with words that are similar or identical in form but different in meaning. The present study aims to identify paronomasia in Arabic and English. To achieve the aim of the study, a corpus of selected verses chosen from two famous figures in Arabic and English literatures and analyzed thoroughly. The analysis of data under investigation reveals that paronomasia is a crucial aid used by poets to portrait the real world as imaginative. It further shows that the concept of paronomasia in English is not the same as in Arabic. In English, there are echoes of the Arabic jinās, i.e., there are counterpart usages of similar devices, yet English rhetoricians have not defined or c

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Publication Date
Sun Jan 20 2002
Journal Name
Journal Of The College Of Languages (jcl)
Domestic Animals in English and Iraqi Rural Proverbs: A Pragmastylistic Study
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Proverbs gain their importance not only from the fact that they represent a cultural record of the people of every nation, but they reveal the way they use language and how they exploit their environments as a good source of inspiration to enrich that language.  Domestic animals, as part of every environment, play a major role in composing proverbs in every nation.

       This study is an attempt to pragmastylistically analyse some selected English and Iraqi rural proverbs using domestic animals in their texts. It limits itself to investigate certain stylistic and pragmatic devices such as: the type of sentences, their lengths, their content and grammatical words, the part of speech used, metaph

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Publication Date
Thu May 21 2026
Journal Name
Al–bahith Al–a'alami
Organizational reputation: A descriptive study of concept development and measurement techniques
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The study aimed to monitor the concept of reputation in the previous literature, its relationship to mental image and identity, and to reveal recent trends in its measurement Techniques.

    The study relied on a descriptive approach using library survey and comparative analysis, and the study reached following conclusions:

     Despite the beginning of the first signs of reputation In the fifties of the last century, however, Defining and standardizing the concept with clear and specific dimensions began in the 1990s and the beginning of the third millennium. The concept of reputation refers to the stakeholders’ overall evaluation of organizations, which reflects their perceptions of

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Publication Date
Mon Oct 01 2012
Journal Name
Iraqi Journal Of Physics
Synthesis and study the electrical properties of carbon nanotubes- polyvinylchloride composites
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The aim of this paper, study the effect of carbon nanotubes on the electrical properties of polyvinylchloride. Samples of polyvinylchloride carbon nanotubes composite prepared by using hot press technique. The weight percentages of carbon nanotubes are 0,5,10 and 20wt.%. Results showed that the D.C electrical conductivity increases with increasing of the weight percentages of carbon nanotubes. Also, the D.C electrical conductivity changed with increase temperature for different concentrations of carbon nanotubes. The activation energy of D.C electrical conductivity is decreased with increasing of carbon nanotubes concentration.

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Publication Date
Sat Jan 01 2022
Journal Name
Materials Research Express
Thermochromic and opacity behaviors in vanadium dioxide nanofilms: a theoretical study
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Abstract<p>Vanadium dioxide nanofilms are one of the most essential materials in electronic applications like smart windows. Therefore, studying and understanding the optical properties of such films is crucial to modify the parameters that control these properties. To this end, this work focuses on investigating the opacity as a function of the energy directed at the nanofilms with different thicknesses (1–100) nm. Effective mediator theories (EMTs), which are considered as the application of Bruggeman’s formalism and the Looyenga mixing rule, have been used to estimate the dielectric constant of VO<sub>2</sub> nanofilms. The results show different opacity behaviors at different w</p> ... Show More
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Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Molecular Structure
Synthesis, biomedical activities, and molecular docking study of novel chromone derivatives
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Publication Date
Thu May 21 2026
Journal Name
Journal Of Physical Education
The Effect of Special Exercises Using Handball R.T On Motor Response Development and Some Goalkeeping Skills For Handball Players from the National Center for Gifted In Handball Aged (15 – 16) Years Old
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Publication Date
Wed Feb 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The development of ethics management system to enhance the social responsibility of government institutions in Iraqi society An analytical study on a sample of top leadership and the presidency of
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Abstract

The objective of this research is to identify the analysis of the ethics of the administration in the development of the social responsibility of one government organizations, and to achieve the objectives of the research was the use of a questionnaire developed for the purpose of data collection and distribution to the research sample, was chosen as a total sample population (50) individuals were relying on statistical package to do a statistical analysis for this research, user, ANSI (SPSS) simple regression analysis, standard deviation, Pearson correlation coefficient.

Research findings show the role of social responsibility in achieving the university's strategy,

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Publication Date
Tue Aug 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Post a reflection on the capabilities of personnel programs A prospective study of a sample of the views of the staff at the Ministry of Higher Education and Scientific Research
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            This research aims to know the role and impact of participation in the capabilities of human resources programs, and for the purpose of measuring it has been determined the dimensions of these two variables by relying on standards for this purpose, was chosen as the Ministry of Higher Education and Scientific Research / device supervision and scientific calendar as one of the important departments in the ministry and includes a large number of individuals at different organizational levels for the purpose of answering a questionnaire prepared for the purpose of measurement and access to the results and the achievement of the objectives of the research and which ha

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Publication Date
Sat Sep 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of knowledge workers characteristics on knowledge acquision “Survey Study of the views of a sample of engineers and technicians in the Directorate of Electricity In the city of Sulaymaniyah
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Purpose: The research aims to diagnose the current availability of knowledge workers characteristics and the role of these characteristics in knowledge acquision in the city of Sulaimaniya Directorate of Electricity, and to identify the differences between personal and occupational characteristics of a sample of research and its impact on the availability of such properties.

Design/methodology/approach :to achieve the objectives of the research questionnaire was developed especially for it and then distributed to a sample of engineers and technicians working in the Directorate of Electricity city of Sulaimaniya, where the sample of the research (52) respondents.

Findings:  the most important conclusions reached

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