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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
Sun Jul 03 2005
Journal Name
Political Sciences Journal
ترجمة (عملية صناعة واتخاذ القرار في السياسة الخارجية للرئيس جورج والكر بوش)
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عملية صناعة واتخاذ القرار في السياسة الخارجية للرئيس جورج والكر بوش

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Publication Date
Thu Dec 31 2020
Journal Name
College Of Islamic Sciences
القصدية في اللغة العربية بين الدراسات القديمة والحديثة: القصدية : قديما و حديثا
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معيار القصديَّة في النص هو من الدراسات الحديثة المتطورة من لسانيات الجملة الى لسانيات النص ، وتحليل الخطاب . والذي يعنى بالطرق والأدوات التي يستغلها المؤلف لتحقيق الغايات المقصديَّة 

وهذا البحث ناقش مفهوم(القصديَّة) لغةً ،واصطلاحاً . فاللغة والكلام شكل من أشكال الوجود الإنساني و( الكلام) هو وسيلة التواصل بين الملقي القارئ ، والمتلقي  السامع ؛ وللتوصل الى الدلالة القصديَّة الدقيقة للغة المنطوقة وا

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Publication Date
Tue Nov 06 2018
Journal Name
Arab Science Heritage Journal
الوسائل الوسائل العلاجيّة الطريفة في التراث العلمي العربي استعمال الأنغام الموسيقية أنموذجاَ
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       The scientific heritage is an essential part of the civilization of nation , so Nations has focused on this aspect in the construction of civilization. So the Arab prosperous scientific achievements is no exception to this general rule in being an integral part of the composition of the Arab- Islamic civilization part ,and when we read in the Arab –Islamic medicine books ,we find the genius of the Arab and Muslims physicians and their own new methods of treatment they use music melodies in medication and treatment of patients

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Publication Date
Mon Jan 23 2023
Journal Name
Arab Science Heritage Journal
العلاقات السياسية والعسكرية للإمارة العلوية في طبرستان مع الإمارة الطاهرية والصفارية والسامانية
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The stage of the establishment of the Alawite state in tabaristan was one of the most important stages in the history of the Shiite sect in Iran

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Publication Date
Wed Dec 30 2015
Journal Name
College Of Islamic Sciences
Historical inductive study on   Ground forces of the army during the first Abbasid era
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This study sought to give a general picture of the organizations and formations of the ground forces of the Abbasid army in its first era, in preparation and armament and continuous development of the mechanisms to help maintain the moral and spiritual morale in the fighting.
Therefore, the caliphs' interest in building the army, organizing it, arming it, choosing competent leaders, and providing them with various weapons in terms of production and storage, as well as taking care of fortifying the cities and gaps in determination and determination, and embarked on construction and restoration, where amazing speed and acted according to the circumstances. During the first Abbasid era, there were significant developments in the military

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Publication Date
Sat Dec 01 2018
Journal Name
Political Sciences Journal
Political development on the royal regime era : A perusal according to the standards of Alexis de Tocqueville
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Abstract: The researcher aims to highlight the historical frames of political development in royal regime era (1921-1949) and study its transitions on social-political aspect for the various periods during this consistent era of Iraq history. As some elements played an important role in shaping this era’s features ,as well as 2hat succeed it, which mainly affected the political progression’s configuration, such as : political culture role, social and cultural foundation, state policy essence and the unofficial institutions remarkable role in influencing public awareness and concerning it's relation to the state ,the clan and religious institutions. The researcher employed Alexis de Tocqueville’s evaluation criteria and indi

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Publication Date
Tue Jan 05 2010
Journal Name
Political Sciences Journal
وقائع واوراق ندوة ( السياسة الخارجية الامريكية في عهد اوباما) / فرع الدراسات الدولية
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وقائع واوراق ندوة (السياسة الخارجية الامريكية في عهد اوباما) التي عقدها فرع الدراسات الدولية في 25 تشرين الثاني 2009

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Publication Date
Sun Nov 04 2018
Journal Name
Arab Science Heritage Journal
شروط شروط الكتابة والوزارة في كتاب النصيحة لقابوس نامه (دراسة تاريخية مقارنة)
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Prince Kikaus  explained  to us Conditions of writing and establishing .Then he touched  upon the Conditions of the ministry and qualities that must be characterized Author and minister both need machines must be availabla in person if given these positions .he was creative in presenting his ideas which is not  without judgment an knowledge.He had a distinct style in mentioned professions and administrative hierarchy As explained in his speech About the writer and his Correspondence and construction and writer position who has developed into a minister then he touched it to the cabinet system and what the minister should do.of qualities .and the importance of the post of minister who mentioned several points to him ou

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Publication Date
Fri Mar 01 2024
Journal Name
مجلة جامعة الانبار للعلوم القانونية والسياسية
السيادة على القدس في الفكر السياسي للاصولية ىالمسيحية المعاصرة( الصهيونية المسيحية انموذجا)
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تعد الصهيونية المسيحية الداعم الابرز للسيادة الصهيونية اليهودية على القدس، ويستند هذا الموقف الذي تتخذه الصهيونية المسيحية الى مجموعة من المعتقدات التي يشكل الاعتقاد بالعودة الثانية للمسيح وتأسيسه لمملكة سعيدة تدوم لالف عام محورها، ليصبح الاهتمام بمستقبل الشعب اليهودي احد الاركان الاساسية لمعتقدات الاصوليون المسيحيون لاسيما الصهيونية المسحية، فالتفسير الحرفي للكتاب المقدس قادهم الى اعتقاد مفاده: ان عو

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Publication Date
Thu Sep 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Interactive Effects of Status Judgments and Individualism -Collectivism Orientation on Organizational Identification
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يهدف البحث الحالي الى استكشاف علاقات التفاعل والتاثير بين الاحتكام للمكانة والتوجه للفردية– الجماعية والدمج التنظيمي مستنداً على مزج اختلاف القيم الشخصية مع افكار نظرية الهوية الاجتماعية لبلورة نموذج البحث. وفي ضوء هذا تم صياغة عدد من الفرضيات التي توضح علاقات التفاعل ما بين ابعاد الاحتكام للمكانة والتوجه للفردية– الجماعية للتنبؤ بوجود الدمج التنظيمي. جمعت البيانات باستخدام استمارة الاستبيان ووزع

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