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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 02 2017
Journal Name
Journal Of Educational And Psychological Researches
اثـر انمــوذج 4EX2 في تعديل الفهم الخاطئ للمفاهيم الكيميائية لطلاب الصف الثالث المتوسط
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The Current research aims to identify ( The effects of 4EX2 Model in Misconception of Chemical concepts and Higher Order Thinking for the Students of the Third grade average ) , To verify the objective of this research , the researchers added nul hypothesis following : There is no difference is statistically significant at the level of ( 0.05 ) between the average scores of students who studied 4EX2 Model and the average students who studied by using the Misconception of Chemical concepts and Higher Order Thinking test. The research was conducted on a sample of the average Third grade students in a Baghdad secretary for boys affiliated to the General Directorate for Educational in Baghdad Al – karkh 3 and for academic year ( 2015 – 2

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Publication Date
Thu Dec 11 2025
Journal Name
Al–bahith Al–a'alami
Challenges Faced by the Media under the Fragile State: Analytical Study of the Iraqi Media Reality
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This study aims at defining the concept of the fragile state, a term that came into existence in 2014, when the states that had internal Problems and external interventions were referred to as the failure states. However, the indicators for their designation and the criteria adopted are 12 indicators that address all aspects of the State’s duties vis-a-vis its citizens. The study examined the reasons that led to the continuation of Iraq within the fragile states, and the selection of the five years within the time limits of the study due to the factors that led to the decline of Iraq and falling back within the most fragile countries. The study dealt with the fragile state challenges to the media reality as a result of the change of it

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Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The tax planning and its effect on the investment: On sample of Iraqi Contribution Company
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The importance of the current study  lies in the  importance of the  Tax policy that  being considered one of the most important tools working on fulfilling  the  social,  financial  and economic  goals  and improving  the investment environment  in the country  to become  having the ability to  activate the  national economy. The current study  has  referred  that  (  Has  the  tax planning  practiced by  the Iraqi  contribution  companies  led to increase  the  far-term tax  outcome through  getting  benefit of   the monetary  funds  and expansion in&nbs

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
الأسطول والقوة البحریة في سلطنة عُمان خلال النصف الأول من القرن التاسع عشر
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Development and progress of the fleet and the navy in Oman during
the reign of Sultan Said bin sultan from 1804 to 1856.
It had second level in Arab Gulf and Indian Ocean during the first half
of nineteenth century. The fleet of Oman in this time became after British
fleet.
Several reasons were behind the development of Omani fleet
- First : The aim of Sultan Said was to built a large navy yard in Arab Gulf
and Indian Ocean to encourage him -to made many ships factories.
- Second: Arab Gulf and Indian Ocean within the reign of Sultan Said
wittinsed the confilicts and wars between different forces it drived Sultan Said
to built agood and strong navy.
- Third The main aim of Oman during the reign of Sultan

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Publication Date
Wed Nov 14 2012
Journal Name
Journal Of The College Of Basic Education,
Effect of mycorrhiza ( Glomus mosseae ) and superphosphate on physiological characters of Hordeum vulgare
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Abstract An experiment was conducted to study the effect of Glomus mosseae and two concentration (21 and 42%) of super phosphate. They used either to be separated or together with inoculation of G. mosseae on physiological characters of Horeum Vulagera . The results showed that all treatment affected significantly especially super phosphate at the above concentration together with G. mosseae. The effects appeared as an increase in plant height , leaves area , dry weight of total plant , stem dry weight , leaves dry weight , tiller’s number , flag leaf area , dry weight of flag and also increased in CGR , RGR , RGR- NAR , LAI . The yield component increased in number of spikes, number of spikelet’s / spike, number of grain / spike, weigh

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Publication Date
Wed Jan 29 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
أثر التمويل الطويل الإجل في صافي الربح: دراسة تحليلية لعينة من المصارف العراقية
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   The research aims to determine the nature of the effect of long . term finance with Net profit which get by the organization from a grubs of finance sources which the organization can choose among them to funding its operations it is  one of the basic necessities Net income . Despite this importance , however there is a distinct lack of many Iraqi organizations in the study of the relationship effect of between these two variables and this the reaserch problem .

          The data of research were obtained the annual guide of Iraqi market for securities where a data of sample of Iraqi Banks was selected which were five banks from 2004 to 2007 , most of the analysis re

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Publication Date
Mon Dec 30 2024
Journal Name
Modern Sport
The Impact of a Psychological Counselling Program on Unconscious Conflicts and Free Will among Coaches of Selected Athletic Disciplines
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هدف البحث إلى بناء مقياسين تخصصين للنزاعات اللاشعورية وحرية الإرادة لمدربي بعض ألعاب القوى والتعرف على مستوى كل منهما لديهم، وإعداد برنامج إرشادي نفسي مستند لرفع مستوى الحالات اللاشعورية وحرية الإرادة للمدربين الذين يعانون من انخفاض مستوى النزاعات اللاشعورية وحرية الإرادة، والتعرف على تأثير البرنامج الإرشادي نفسي في النزاعات اللاشعورية وحرية الإرادة لدى مدربي بعض ألعاب القوى، لتفترض بذلك الباحثة بإ

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Publication Date
Sun Jun 21 2020
Journal Name
Baghdad Science Journal
Detection of Aflatoxin B1 among Early and Middle Childhood Iraqi Patients
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      The study was conducted for the detection of Aflatoxin B1(AFB1) in the serum and urine of 42 early and middle childhood patients (26 male and  16 female ) with renal function disease, liver function disease, in additional to atrophy in the growth and other symptoms depending on the information within consent obtained from each patient, in addition to 8 children, apparently healthy, as  the control. The technique of HPLC was used for the detection of AFB1 from all samples. The results showed that out of 42 patient children, 19 (45.2%) gave positive detection of AFB1 in the serum among all age groups patients with a mean of 0.88 ng/ml and a range of (0.12-3.04) ng/ml. This was compared with the cont

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Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
دور الاعتماد المزدوج للكلفة التاريخية والقيمة العادلة في تحقيق ملائمة وموثوقية البيانات المالية
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Performance measurement is considered one of the most important issues in

Measuring performance effectiveness in the educational institutions by maintaining balance among quantity measurable factors. They can be financial or non‐financial factors. Consequently they reflect decisive factors in the success of educational institutions and determining suitable standards and dimensions for their activities and giving it proportional importance. Adopting the idea of Balanced Score Card as one of the modern administrative techniques and methods by educational institutions assists in the development of administrative work, adjusting the performance in addition to achieving comprehensive standard and development of educational universit

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Publication Date
Fri Sep 01 2006
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
تقييم الأساليب و المؤشرات المالية في تحديد كفاءة وفاعلية وإصلاح أنظمة المؤسسات المصرفية
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تلعب المؤسسات المصرفية دورا مهما و رئيسيا في اقتصاد أي بلد من خلال قيامها في تعبئة مدخرات المجتمع و من ثم توجيهها نحو الفرص الاستثمارية المختلفة التي تزيد من معدلات النمو الاقتصادي و التوظيف الكامل للموارد وكما هو معروف  فأن الجهاز المصرفي يؤدي مهام اقتصادية تخضع للتغيرات المستمرة و على الرغم من ان وظائفه التقليدية لازالت على حالها ألا وهي قبول الودائع و منح القروض و التسهيلات الائتمانية نجد أن الوسائل و

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