Preferred Language
Articles
/
alkej-389
Transient Behavior Analysis for Solar Energy Storage in PCM-CFM Material Using Equivalent Heat Capacity Method as Storage Model
...Show More Authors

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%.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Oct 07 2021
Journal Name
مجلة لارك للفلسفة واللسانيات والعلوم الاجتماعية
معايير النخبة الاكاديمية العراقية في التعرض للقنوات الفضائية الاخبارية الاجنبية الناطقة باللغة العربية
...Show More Authors

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
...Show More Authors

         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

... Show More
View Publication Preview PDF
Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
تجلیات اللغة الایحائیة في دعاء الصباح للامام علي بن ابي طالب (علیھ السلام)
...Show More Authors

The literary aspect of any text reveals when it used The inspiration language
which reveals the creative aspect of language for the creator (writer) he in turn
will seek for the best choice from these aspects then, he will distribute them due
to their intention, and according to the their context
Thus, propagandistic text contains many moral features which the language
accord to thus , we found that the morning (dua al asbah)is full of creative
literary manifestations through many abstentions which happened in different
structures that contain the text, especially in structure of metaphor, and contrast.
we found many outstanding gaps and abstentions in these are given life, matter
that gives the text the most l

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 07 2019
Journal Name
Arab Science Heritage Journal
دور دور العرب والمسلمون في نشر محاصيل الخضر والفواكه التي إلى دول العالم
...Show More Authors

     شهد العصر الذهبي للإسلام تحول أساسي في مجال الزراعة عرف باسم "الثورة الزراعية الإسلامية" أو" الثورة الخضراء"  أو "الثورة الزراعية العربية" ، وقد أتاح الوضع الاقتصادي العالمي الذي أسسه التجار المسلمون في جميع أنحاء العالم القديم ، نشر العديد من النباتات والتقنيات الزراعية بين أجزاء مختلفة من العالم ا

... Show More
View Publication Preview PDF
Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
" أثر استراتيجية الجيجسو في تحصيل مادة الجغرافيا وعمليات العلم لدى طالبات المرحلة الاعدادية"
...Show More Authors

The goal of current researcher to know the impact of strategic Jigsaw in the collection of hypertext and geographic operations of science students at the preparatory stage And that by checking the following 1.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional degrees in the average achievement in the subject of geographical 2.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional av

... Show More
View Publication Preview PDF
Publication Date
Mon Nov 08 1013
Journal Name
كلية الفنون الجميلة
إشكالية الخطاب الجمالي للجسد في النحت العالمي المعاصر، دراسة على وفق المنهج الظاهراتي
...Show More Authors

اهتم في الربع الأول بالمفاهيم النظرية للمناهج التي تقع في النقاط الخمس ، النقطة الأولى تتعلق بمفهوم الخطاب والخطاب المادي ، وقلنا أن الرسالة كانت مبنية على الجسد من البداية ، حتى قبل ذلك هناك ستكون فلسفة أو معرفة المنظمة. أما النقطة الثانية فتتعلق بالمفهوم الفينومينولوجي للخطاب ، ونحن في هذه المرحلة أهم الركائز التي قام عليها (إدموند هوسرل) في بناء مفهوم وصفي ضعيف. في النقطة الثالثة نكشف عن الظواهر المتعلقة ب

... Show More
View Publication Preview PDF
Publication Date
Tue Jan 05 2010
Journal Name
Political Sciences Journal
بعض الملاحظات على القانون رقم 35 لسنة 2007 قانون العمل الصحفي في كوردستان
...Show More Authors

بعض الملاحظات على القانون رقم 35 لسنة 2007 قانون العمل الصحفي في كوردستان

View Publication Preview PDF
Crossref
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.
...Show More Authors

    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

View Publication Preview PDF
Crossref
Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The causal relationship between debt size and Economic value added With contrast of the Frim Size
...Show More Authors

Abstract

       The research aims to identify  the  nature of  the relationship between the level of debt used  and economic  value  added  of companies listed on the Iraq Stock Exchange under the Contrast sizes of these companies , The research addressed the theoretical concepts associated with each of the debt financing , economic added value and Organization size With the use of financial techniques in the practical side to measure these variables, The research community Represent of  the shareholding companies listed on the Iraq Stock Exchange with a choice of intentionally sample of 24 joint stock companies representing&nbsp

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of selection of employee's strategy on human capital/ (Field research at the University of Baghdad)
...Show More Authors

Abstract:

This research aims to know the reflection of selection of employees strategy dimensions ( selection of employees strategy standards, procedures selection of employees strategy , efficiency based on a selection of employees strategy) on human capital (knowledge, skills, abilities) in a sample of Lecturers consists of (Deans and assistants and heads of departments) in ( Baghdad University) included nine colleges and university president as total sample size (54), which represent almost 50% of the total research community of 116, was used in the light of the objectives of the research descriptive and analytical approach, has been a resolution main tool for data collection as well as the interview p

... Show More
View Publication Preview PDF
Crossref