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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 Nov 12 2018
Journal Name
Arab Science Heritage Journal
المساواة المساواة بين الرجل والمرأة في ضوء القرآن الكريم دراسة تفسيرية ـ موضوعية
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 It was the most important weapons that were used during the long cultural war standing against Islam, it is interesting colonists Muslim women special attention, and directed to lure women rebellion against religion, and go out on their own teachings in this religion,

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Publication Date
Thu Dec 13 2018
Journal Name
Arab Science Heritage Journal
تخطيط تخطيط عمارة المدن الإغريقية "دراسة تخطيطية ورؤية تاريخية في ملامح الحضارة الإغريقية"
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The architecture Greek first civilizations, which focused on the design and planning of cities taking into account the percentages aesthetic and artistic forms beautiful and characterized Greek civilization styles three league and Ionian and Corinthian, has launched these names on this models relative to the form of

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Publication Date
Sun Jan 17 2021
Journal Name
Arab Science Heritage Journal
قراءة تحليلية في كتاب الاصول للسيد محمد باقر الصدر واثره على الدراسات المعاصرة.
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    In the subject area (participation and tandem), the study showed the views of Mr. Sadr in this field when researching first: the issue of the necessity of these two phenomena in the language that some imams of the language and principles called for to discuss and respond to, and

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
The role of salt stress on laboratory cultivation of green macroalga Enteromorpha compressa and its antioxidant activity
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Cultivation of the green seaweed Enteromorpha compressa was performed under natural laboratory spring environmental conditions of temperature, light intensity and photoperiod to study the salinity tolerance of this intertidal green macroalga. Cultivation was carried out under artificial seawater (ASW) of different concentrations (18, 35, 53 and 106 g/l sea salt) compared to the control using natural seawater (NSW). Growth rate and pigment content of the cultivated alga were recorded at regular intervals during the experimental duration. Antioxidant activity of the crude ethanolic extract and its fractions (petroleum ether, chloroform, ethyl acetate and acetone) was performed against DPPH radical scavenging assay and compared to

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Publication Date
Wed Jan 01 2025
Journal Name
International Journal Of Research In Social Sciences And Humanities
توظيف الذكاء الاصطناعي في العلوم الإسلامية وخدمة الدين الإسلامي وكيفية تجنب التحيز فيه
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يُعد موضوع الذكاء الاصطناعي اليوم أحد أبرز القضايا التي تشغل الباحثين في التكنولوجيا العالية والدقيقة ، وكذلك في باقي الحقول الأخرى نظراًّ لربطها بالمنتجات والخدمات البشرية من أجل تقديم عدة مساهمات الغرض منها تبسيط وتسهيل الحياة الانسانية في مختلف المجالات في حالة إذا ما تم استخدامها وفق نهج أخلاقي مستدام يتضمن مجموعة من المبادئ كالعدالة والموضوعية والشفافية والمساءلة والمساواة ، وهي مبادئ تهدف بشكل عام

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Publication Date
Thu Jul 02 2009
Journal Name
Journal Of Educational And Psychological Researches
التكيف للحياة الجامعية وعلاقته بالصف الدراسي لدى طالبات الاقسام الداخلية في الجامعة المستنصرية
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يواجه الكثير من الافراد مشكلات في التكيف، خاصة الطلبة الذين ينتقلون من المرحلة الدراسية الثانوية الى المرحلة الجامعية، حيث يرافق هذه البيئة الثقافية الاجتماعية العديد من الضغوط والمواقف التي تحتم على الطالب الوصول الى تكيف مثالي.

ان التعليم الجامعي يوفر مجالات عديدة للتخصص تعمل على تحقيق طموحات الشباب التي تناسب قدراتهم وميولهم واهتماماتهم، وهو بذلك يمثل نوعية من التعليم تختلف عن النم

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Joint audit and its impact on the market value of firms listed on the Iraq Stock Exchange
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The research aims to investigate the possibility of joint auditing in improving the market value of Iraqi companies listed on the Iraq Stock Exchange. The sample was represented by 10 Iraqi companies listed in the Iraq market for the period from 2014-2017 (2 years before implementation and 2 years after implementation) and the research was based on the idea that joint auditing enhances investor confidence and raises their level of security as a result of providing quality and reliable reports, and thus This indicates good news in the market that reflects on the performance of stocks and the market value of companies that adopt joint auditing. The results of the analysis indicate an improvement in the market value, but this improv

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of The College Of Languages (jcl)
הסיפור העברי באמריקה ברבע השני של המאה ה-20 הסופר שמעון הלקין כדוגמה
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                                      הסיכום

          הסיפורת העברית באמריקה, הייתה קשורה בסביבה מסויימה. גם כן היא קשורה בנושאים מסויימים, ורובם היו מדברים על חיי היהודים באמריקה.

            דמותו של שמעון הלקין קבועה בנפשם של המבקרים כזו של משורר בעי

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Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Assessment of Air Pollution around Durra Refinery (Baghdad) from Emission NO2 Gas at April Month
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Nitrogen dioxide NO2 is one of the most dangerous contaminant in the air, its toxic gas that cause disturbing respiratory effects, most of it emitted from industrial sources especially from the stack of power plants and oil refineries. In this study Gaussian equations modelled by Matlab program to state the effect of pollutant NO2 gas on area around Durra refinery, this program also evaluate some elements such as wind and stability and its effect on stacks height. Data used in this study is the amount of fuel oil and fuel gas burn inside refinery at a year 2017. Hourly April month data chosen as a case study because it’s unsteady month. After evaluate emission rate of the all fuel and calculate exit velocity from

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Publication Date
Wed Jun 30 2021
Journal Name
College Of Islamic Sciences
The footnote of The Scholar Abdul Rahman Al-Penjawni on collecting mosques and explaining it to the local by the scholar Abdul Rahman Ibn Mulla Mohammed Ibn Mulla Tahir Al-Penjweni Died in: 1319 AH School: (Absolute and restricted) Study and Observation
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Abstract

Indeed, being busy with the understanding of religion is the best sort of worship that the almighty God has given each period of time a number of scholars and wise men. They receive what has been passed down to them from their great ancestors, and those who are willing to learn will learn, their students preserve their knowledge through teaching and writing. Thus, the scholars were pioneers in this field due to the value and importance of their knowledge. They have strived in learning, explaining, and writing new subjects.

One of those scholars is sheikh (Abdulrahman Al-Penjweni) who passed away 1319 AH in one of the villages of the city of Sulaimani in Iraq. He was one of the wisest scholars, a br

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