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alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
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A paraffin wax and copper foam matrix were used as a thermal energy storage material in the double passes air solar chimney (SC) collector to get ventilation effect through daytime and after sunset. Air SC collector was installed in the south wall of an insulated test room and tested with different working angles (30o, 45o and 60o). Different SC types were used; single pass, double passes flat plate collector and double pass thermal energy storage box collector (TESB). A computational model based on the finite volume method for transient tw dimensional domains was carried out to describe the heat transfer and storage in the thermal energy storage material of collector. Also, equivalent specific heat method was employed to describe the heat storage and release in the mushy zone. Experimental results referred to an increase in thermal conductivity of paraffin wax that supported by copper foam matrix more than ten times. While the ventilation effect was still active for hours after the sun set, depending on the heat storage amount. Maximum ventilation mass flow rate with TESB collector was recorded with value equals to 36.651 kg/hr., when the overall discharge coefficient that was calculated for the system equals to 0.371. Experimental results showed that the best working angle range was 45~60o, and the highest air to the collector approaching temperature appeared to the double passes flat plate collector. Results gave greater heat storage efficiency of (47)% when the maximum solar radiation was 780 W/m2 at 12.00pm, while the energy summation through duration charge time was 18460 kJ. Computational results, depending on the equivalent heat capacity method for heat storage or release from phase change material that supported by copper foam matrix, showed the behavior of paraffin wax melting and solidification situation through periodic for charge and released heat from the solar collector. Also, these results gave agreement approaching the experimental results for the heat storage in the combined heat storage material, with standard error of 16.8%.

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Publication Date
Wed Dec 20 2023
Journal Name
Arab Science Heritage Journal
بعض وظائف النبي صلى هللا تعالى عليه وآله وصحبه وسلم الواردة في القرآن الكريم
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The research included an introduction, and three functions
of the Prophet (peace and blessings of Allaah be upon him), a
machine and a companion, and a conclusion , the first function,
which is zakaah, and began with it because it is the basis of every
work, no work is accepted by Allaah except what was sincere to
him, as well as sincere intention, because accepting works is
entrusted with the

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Publication Date
Wed Oct 01 2008
Journal Name
Journal Of Educational And Psychological Researches
الضغوط النفسية والعوامل الاجتماعية المؤدية إلى الإصابة بأمراض القولون ( بحث ميداني في مدينة بغداد )
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بالنظر الظروف الراهنة التي يمر بها قطرنا ونتيجة للارتفاع معدل الاصابة بالامراض ذات الطابع النفسي جسمي او ما تعرف بامراض سوء التكيف الناتج عن الضغوط النفسية المستمرة.

ارتأت الحاجة الى دراسة هذا النوع من المرض والتي ترجعها الباحثة الى الاسباب التالية :.

1-تعرض المواطن العراقي الى ضغوط نفسية مستمرة متمثلة بحالة الانفلات الامني والشعور بالقلق المستمر المراف

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Publication Date
Sun Apr 01 2007
Journal Name
Journal Of Educational And Psychological Researches
القدرة على القيادة التربوية وعلاقتها بالاتجاه العلمي لدى رؤساء الاقسام في بعض الجامعات العراقية
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مشكلة البحث :

تعد الادارة الجامعية عاملا مهما واساسيا في اكمال البناء المعرفي لشخصية الطالب الجامعي لما يمثله من قدرة على قيادة العملية التربوية والتعليمية والوصول بها الى تحقيق اهدافها . وطالما كانت هذه الادارة ممثلة ابتداء من رئاسات الاقسام ووصولا الى اعلى الهرم الاداري في الجامعة مهمة في تحقيق  الاهداف العلمية والتربوية فان اختيار الاشخاص للقيام بمهامها تاخذ جانبا كبيرا ومهما وذلك للاثر

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Publication Date
Fri Jun 01 2007
Journal Name
Journal Of The College Of Languages (jcl)
Molla Mehmet Sadık'ın Kerkük'teki Eskide Bulunan Taş Köprü Adlı El Yazısının İncelemesi Açıklaması
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Yaşıyan kuşağın unutulmaz aruz şairi tanınmış Hacı Mehmet Sadık. İzi
silinmez kaybin, bugünkü eski sitil şiirin gerçek sembolu olup yaşadığı bir çağa
yakın süre içinde yüzlerce ve yüzlerce beyit şiir söylemiş.
Her çevrede Türk doğup Türk yaşamak bahtıyarliğiyle övünen ozanımızın ,
seçkin bir çok şiirleri vardır.
Böylece kitap, dergi ve gazetelerde yayımlanmış sayısız şiirleri yanında
basıma hazır kitaplık şiir ve yazılarıda vardı. Gazetelerde yayımlanan şiirlerini
memleket dertlerine , değerli mert kişilerine gönüllerde yaşıyan ölülerine , yurdu
ve yurttaşı için iyilik güden devlet ve memleket büyüklerine ayırdığını
görmekteyiz.<

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Publication Date
Fri Aug 01 2025
Journal Name
مجلة كلية التربية الاساسية
The Effect of the Cornell Note-Taking Strategy on Systematic Thinking Skills Among Second-Year Intermediate Female Students
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The current research aims to identify the effect of the note-taking strategy (CORNELL) on systematic thinking among second-grade female students in government daytime secondary and intermediate schools. Al-Fadhila School was intentionally chosen to be its student sample for the research affiliated with the First Karkh Directorate for the academic year (2024-2025). Then one of the two sections was randomly chosen to represent the experimental group that studies according to the note-taking strategy (CORNELL) and the other the control group that studies according to the usual method. The equivalence of the two research groups was verified by a set of variables, which were represented by chronological age in months, previous achievement in che

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Publication Date
Mon Mar 11 2019
Journal Name
Baghdad Science Journal
Assessment of Azotobacter chroococcum’s Ability to Produce Hydrolytic Enzymes and Enhance Growth of Vicia faba
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A. chroococcum isolate was examined for its ability to produce the hydrolytic enzymes chitinase, pectinase, protease, and lipase, in an effort to enhance the growth of fava bean (Vicia faba). Biological experiment was conducted in pots with complete random design (CRD). The experiment includes three treatments: control (plant without treatment) (P), NPK fertilizer (plant + fertilizer) (PF), and A. chroococcum inoculum (plant + A. chroococcum) (PA). These treatments were performed with sterile and non-sterile soil, which were planted with fava beans. At the end of experiment (seven weeks from planting), length and weight of plant shoot and plant root were calculated. The results show that the isolate wa

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Publication Date
Thu Mar 01 2007
Journal Name
Al-khwarizmi Engineering Journal
Laminar Natural Convection of Newtonian and Non – Newtonian Fluids Inside Triangular Enclosure
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In the present work, steady two – dimensional laminar natural convection heat transfer of Newtonian and non-Newtonian fluids inside isosceles triangular enclosure has been analyzed numerically for a wide range of the modified Rayleigh numbers of (103Ra ≤ 105), with non-dimensional parameter (NE) of Prandtl – Eyring model ranging from (0 to 10), and modified Prandtl number take in the range (Pr* =1,10, and 100). Two types of boundary conditions have been considered. The first, when the inclined walls are heated with different uniform temperatures and the lower wall is insulated. The second, when the bottom wall is heated by applying a uniform heat flux while the inclined walls at

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Publication Date
Sat Jan 02 2021
Journal Name
Journal Of The College Of Languages (jcl)
Euphemism from a Politeness Perspective: An Exploration of the ability of Iraqi EFL learners to Use and Comprehend Euphemistic Expressions
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Euphemisms are advantageous in people’s social life by turning sensitive into a more acceptable ones so that resentful feelings and embarrassment can be avoided. This study investigates the ability of Iraqi English learners in using euphemistic expressions, meanwhile, raising their awareness and the faculty members in English teaching faculties regarding the relevance of discussing the topics that demand euphemisation. This study comprised three stages: initial test, explicit instruction with activities, and a final test for the students’ development in this domain. A test has been distributed among 50 respondents, who are at the fourth year of their undergraduate study at the University of Babylon/ College of Basic Education. The lo

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Publication Date
Fri Dec 01 2023
Journal Name
Political Sciences Journal
Exploring the Effects of European Union Conditionality Language on European Mediterranean Human Rights Dialogue
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Since more than a decade, human rights dialogue in the European Mediterranean Region has been marked by a number of tensions. Although a number of factors contribute to such disputes, the effect of human rights conditionality, which ties EU economic cooperation progression with partner countries human rights advancement, on the dialogue has not been studied. Understanding the aspects, impacts, and effects of conditionality on Euro-Med relations is crucial for furthering dialogue. Yet this variable has been almost entirely neglected in academic and policy research. The research concludes several direct and indirect impacts of conditionality on human rights dialogue using a mixed methodology approach. Direct effects are reflected in the wi

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Publication Date
Mon Feb 14 2022
Journal Name
Journal Of Educational And Psychological Researches
An Investigation of the Relationship between Writing Achievement and Writing Strategy Use by Secondary School Students
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Basically, this study aims to identify the extent to which Iraqi secondary school students use writing strategies and how proficiency level and students gender could affect writing strategy use. The study also examines the relationship between writing achievement and writing strategy use among Iraqi secondary school students. For this purpose, 140 Iraqi secondary school students were selected randomly from six different schools. Petric and Czarl’s questionnaire (2003) was adopted in the study as an instrument to collect the needed data. A software of SPSS used to analyze the collected data. The findings revealed that secondary school students appeared as low users of writing strategies; low proficient students do not show a sta

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