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%.
This research aims to reveal the impact of applying a teaching course in
gaining and preserving information by female students comparing with the
traditional method, through testing the two following hypotheses:
1. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the control group of female students taught using the traditional
method.
2. There is no difference with statistical significance at the level of
significance (0.05) between the average grades achieved by the
experimental group of female students taught using a teaching course,
and the contro
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 
... Show MoreThe 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
The study aimed to know the effect of the use alcoholic ethanol extraction of Boswellia Carterii In prolonging the period of preservation cooled ground meat in 4C for 6 days, it has been mixing ground meat with 150,300,450 mg/ml of alcoholic extract Consecutive, Where (0 was the control sample), All samples were stored separately for 0 , 3 , 6 days in Refrigerator temperature 4 C, Conducted by some microbial tests, Results have shown that mixing the ground meat with Boswellia Carterii extraction Led to prolong the storage of meat for 6 days at 4 C .and the Best result came when adding alcoholic ethanol extract of Boswellia Carterii by 450mg/ml Which Equal 0.9 g ,that reducing microbial load more higher than 150&300 mg/ml. All of thes
... Show MoreThe Local and Global Corporations are suffering of managerial and financial corruption phenomena, which leads them to loss and bankruptcy. So, it is necessary to search for tools which help prevent phenomena like this, and one of these tools is (corporate governance) which represent controlling tool that contribute in reducing corruption. this study aims at modifying (corporate governance system)in order to make it suitable with Iraqi government Corporations. the study depend upon main hypothesis which is (the performance level of the strategic perspective of governance system is depending upon work according to the perspective dimensions itself. From the main conclusions:-It is possible to building a strategic perspective
... Show Moreإن التطور الهائل في منظومة تكنولوجيا المعلومات والاتصالات في العالم , أثر كثيراً في الجوانب الحياتية والاجتماعية والاقتصادية والسياسية والثقافية عامة والتربوية والتعليمية خاصة, إذ أصبح لها دور كبير في تسيير الكثير من الأمور. ولا بد من القول ان المؤسسات والمنظمات لا يمكن ان تنتقل من القرن العشرين الى القرن الحادي والعشرين إلا إذا أفادت من تكنولوجيا المعلومات والاتصالات, إذ توافر هذه التكنولوجيا الكثير من ال
... Show MoreEthanolic crude extracts of leaves from Laurus nobilis and Alhagi maurorumfor were screened for alkaloids, saponins, tannins, anthraquinones, steroids, flavonoids, glycosides, and glucosides contents. Biochemical activities, including antibacterial activity, antioxidant, and antihemolytic activity, were investigated. Antibacterial activity against Three types of pathogenic bacteria was detected by disc diffusion analysis and characterized by zone of inhibition (ZOI). Antioxidant properties were determined by a diphenyl-1- picrylhydrazyl (DPPH) method. Results revealed that the inhibitory activity of the plants against G+ve and G-ve bacteria were different, where the greatest ZOI of Alhagi maurorum a
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ABSTRACT
The researcher seeks to shed light on the relationship analysis and the impact between organizational values in all its dimensions (Administration Management, Mission, relationship management, environmental management) and strategic performance (financial perspective, customer perspective, the perspective of internal processes, learning and development) in the presidency of Two Universities of Baghdad & Al-Nahrain, it has been formulating three hypotheses for this purpose.
The main research problem has been the following question: Is there a relationship and the impact of bet
... Show MoreThe global challenges of contemporary facing societies urge to seek and move to adopt the style conscious in the face of these challenges and work on the investment of human resources and energies humanitarian efficient and effective for the development of the institutional and Management and make it more efficient and effective and meets the requirements and keep pace with global developments , and more aspects of managerial aim is Total Quality Management , as it has become thanks to the sheer amount and large accelerated technical developments and information and communication technologies , which feature of this era , and in the field of education , the charge of it are seeking through the application of total quality management to b
... Show Moreلم يكن من السهولة على الباحث في مجال التربية والتعليم تحديد مراحل التعليم في العصر العباسي الأخير او وضع فواصل محددة بين تلك المراحل المختلفة من ذلك العصر، لان التعليم آنذاك كان يتميز بالمرونة التي تتيح للتعليم الحرية المطلقة في اختيار نوع الدراسة والمادة الدراسية التي يريد دراستها.
فكانت المساجد والكتاتيب والمجالس العامة والخاصة هي المؤسسات العلمية الاولى للتعليم عند المسلمين في عهد ال
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