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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
Mon Jun 01 2020
Journal Name
مجلة جامعة الانبار لللعلوم القانونية والسياسية
تقويم قواعد إدارة الشركات في ضوء قانون الشركات العراقي رقم 21 لسنة 1997،
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تقويم قواعد إدارة الشركات في ضوء قانون الشركات العراقي رقم 21 لسنة 1997،

Publication Date
Sat Jul 01 2017
Journal Name
Al–bahith Al–a'alami
The effects of Internet use on university’s students: “A Study on a Sample of Jordanian University’s students "
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The effects of Internet use on university’s students:The effects of Internet use on university’s students:“A Study on a Sample of Jordanian University’s students "This survey aims to identify the most important effects of Internet use on Jordanian public and private universities’ students by monitoring and analyzing a set of indicators that show the quality of the effects on specific fields such as  cultural, social, psychological, moral and political effects .To achieve these goals, the study attempts to answer the following questions:1.   What are the effects of Internet’s use on students?2. What is   the relationship between the effects and demographic variables such as  gender, age, family size an

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Publication Date
Thu Dec 22 2022
Journal Name
مجلة الزرقاء للبحوث والدراسات
صياغة استراتيجية الامن القومي للدولة في ضوء ادراك التهديدات المتغيرة : الاستراتيجية الروسية انموذجا
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Publication Date
Mon Jun 04 2012
Journal Name
المؤتمر العلمي الدولي الاول
اهمية بعض القياسات الجسمية والبدنية بمستوى الانجاز الرقمي في فعاليه التجديف (الكاياك) 200م
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Publication Date
Fri Mar 15 2019
Journal Name
Al-khwarizmi Engineering Journal
Studying the effect of Different wt % AL2O3 Nanoparticles of 2024Al Alloy / AL2O3 Composites on Mechanical Properties
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The nanocompsite of alumina (Al2O3) produced a number of beneficial effects in alloys. There is increasing in resistance of materials to surface related failures , such as the mechanical properties , fatigue and stress corrosion cracking .The experimental results observed that the adding of reinforced  nanomaterials  type Al2O3  enhanced the   HB hardness, UTS, 0.2 YS and ductility of 2014 Al/Al2O3 nano composites . the analysis of experiments, indicated that The maximum enhancement was observed at 0.4 wt.% Al2O3. The ultimate improvement percentage were 15.78% HB hardness, 18.1% (UTS), 12.86% (

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Publication Date
Thu Oct 30 2025
Journal Name
Al–bahith Al–a'alami
Radio Republic of Iraq and Awareness Promoting of Minorities’ Rights
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Proposals to raise awareness of the rights of minorities and secure their freedoms have begun to receive attention Internationally. It is escalated, especially after the increasing impact of wars and conflicts on these situations Minorities, and UNESCO stresses the need to take over information and communication policies Greater attention to protect minority rights.

Hence the importance of our research, the problem of which lies in the main question: (What is the role Radio Republic of Iraq has played in promoting awareness of minority rights at the level : Public and  Social?) . As one of the Iraqi media networks , laws oblige them to pay attention to the rights of minorities and to spread a culture of pluralism , diversity

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Publication Date
Mon Sep 15 2025
Journal Name
مجلة الانبار للقانون والعلوم السياسية
الصراعات الدولية وانعكاساتها على الامن الانساني في منطقة الشرق الاوسط بعد عام 2003
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تعد ظاهرة الصراعات ظاهرة قديمة كقدم الوجود البشري وهذا يطبق على المستوى الدولي مما يجعل الدول الصغرى هي ساحة تصفيات كما هو الحال في سوريا مما يجعل الامن الانساني فيها معدوم

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Publication Date
Thu Dec 30 2021
Journal Name
College Of Islamic Sciences
منظومة القيم في الحوار مع المخالف عبر التاريخ: حوارات الصحابة ٪ مع الخوارج أنموذجاً
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The research goes to clarifying the system of values ​​in dialogue with the violator through an inspection of our cultural heritage, and our inherent religious values. Al-Rashidah, and this position is represented in their various and varied dialogues with the Kharijites, whether that was at the beginning of their appearance - as is the case in the dialogue of Ali and Ibn Abbas, may God be pleased with them - or after the formation of their teams and the strength of their thorns, as in the dialogue of Ibn al-Zubayr and Jabir bin Abdullah, may God be pleased with them.

In these dialogues, I found important values ​​in the dialogue, which it is good to draw upon and work on, especially with the extremist currents in our tim

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Publication Date
Sun Oct 03 2010
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Applying K-W-L Technique on Teaching ESP Students
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         Over the last few decades, many instructors have been trying all kinds of teaching methods, but without benefit. Nevertheless, in the 1986, a new technique is appeared which called K-W-L technique, it  is specified for reading comprehension passages because reading  skill is not easy matter for students for specific purposes (ESP).therefore, the K-W-L technique is a good one for thinking and experiences. To fulfill the aims and verify the hypothesis which reads as follows" it is hypothesized that there are no significant differences between the achievements of students who are taught according to K-W-L technique and those who are taught according to the traditional method

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Publication Date
Thu Nov 08 2018
Journal Name
Arab Science Heritage Journal
الاحوال الأحوال العامة للأندلسيين في غرناطة بعد انتهاء الحكم العربي الإسلامي دراسة تاريخية
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The harsh human suffering experienced by the Andalusians were a religious conflict and racist impact on all aspects of public life. The religious factor most important factors that determined the nature of the hostile relationship between the Andalusian and Castilian, Castile has sought to make them Christians by force through laws that deprived them of all their rights. In spite of the large number of those laws, the authority admitted inability to subdue the Andalusians to its will through the issuance of the final decree of expulsion.

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