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
Fri Jun 30 2017
Journal Name
Journal Of Madenat Alelem University College
دراسة خلايا البشرة والمعقدات الثغرية للسيقان والكساء السطحي لبعض المراتب من عائلة عرف الديك Juss. Amaranthaceae في العراق
...Show More Authors

Gompharena globosa L., Irisene herbistii Hook. ex Lindl. The results of this study showed that the anatomical characters of the stems epidermis and the indumentum covering different parts of the plant have an important anatomical characters such as the cell wall shape of ordinary epidermal cells also the shape and type of stomata, their presence in some taxa and abscent in others. The hairs also differentiated by their shapes and them types, either they glandular or eglandular also they are different in distribution between the different taxa or in the some taxon.

Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
The Chinese-Russian role towards the Iranian nuclear program)An analytical study of formation and development according to international variables and future prospects(
...Show More Authors

The Iranian nuclear program was one of the most prominent issues in the international arena, in light of Iran's insistence on using it in various ways, and according to international changes, it came under pressure from the American side to impose packages of sanctions, which continued to our time, as it went to Russia and China to gain support in developing its nuclear activities. And, by virtue of the common interests that are linked between them, Iran has received great support from the last two countries in all fields to reach the final agreement in 2015, regarding asserting the peace of these activities, in addition to lifting all restrictions represented in the previous sanctions according to the Security Council resolutions, Aldo

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Sep 30 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Internet banking services and their impact on customer's: Applied Research on Sample of Iraqi Commercial Banks
...Show More Authors

This research examines the issue of Internet banking services and their impact on customer's perceived value to know the potential of Iraqi commercial Banks to provide Internet banking services as well as determine the customer's level of perception of the value of such services. The research aims to demonstrate the effect that Internet banking services have on the customer's perceived value and to find how online banking services can be used to add value that the customer perceive. The main findings were that research sample banks don't have a sophisticated network of electronic Windows through which banking services are provided to allow customers to manage their accounts, and perform various operational operations through the

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 30 2018
Journal Name
College Of Islamic Sciences
Biography Judge Faqih Abu Bakr al-Ansari and its impact on the notation Hadiths (36 AH - 120 AH / 657 AD - 738 AD)
...Show More Authors

Followers and their followers (may Allah be pleased with them all) followed the approach of the guidance and the Sunnah of the Messenger of Allah Muhammad (peace be upon him) in the collection and codification of the hadith of the Prophet Muhammad in various Arab and Islamic areas. Subsequent judge Faqih Abu Bakr al-Ansari had a distinct effect during that time immortalized in the pages of our Islamic history in preserving the Sunnah of our great Prophet Muhammad (PBUH) and documenting the constants of Sharia and Islamic jurisprudence and its importance in the activity of intellectual and scientific movement in the Arab Islamic State.

View Publication Preview PDF
Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
تصميم نظام مقترح لتخصيص مهام العمل لمحطات العمل وباعتماد الطرق الاجتهادية دراسة حال في الشركة العامة للصناعات الكهربائية
...Show More Authors

This research work dealt with the problem of layout the production line of engine of fan roof at the General Company for Electrical Industries (GCEI). It was observed that the assembly line of engine was unstable and subject to severe fluctuations. In addition the execution of tasks at some stations was observed to be very fast while at other stations was slow. This phenomenon resulted into bottlenecks between workstations, idle time, and work in process. The system design was used to assign tasks to work stations according to different heuristics (Ranked Positional weight techniques, longest Task Time, Most following tasks, Shortest tasks time, Least number of following task).

The study revealed that th

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jul 01 2019
Journal Name
مجلة الجامعة العراقية
القياس المحاسبي عن التنمية المستدامة واثره على تقارير الابلاغ المالي نموذج مقترح (دراسة في الشركة العامة للمنتوجات الغازية)
...Show More Authors

هدف البحث الى التعرف على القياس المحاسبي عن التنمية المستدامة، وبيان العلاقة بين القياس المحاسبي عن التنمية المستدامة وتقارير الابلاغ المالي، وكذلك بيان أثر القياس المحاسبي عن الاستدامة على تقارير الإبلاغ المالي في الشركة العامة للمنتوجات الغازية، وقد تمحورت مشكلة البحث في بيان أثر عناصر المحاسبة عن التنمية المستدامة، البيئية، والاجتماعية، والاقتصادية، على تقارير الإبلاغ المالي في الشركة العامة للمنتو

... Show More
View Publication
Publication Date
Tue Sep 27 2022
Journal Name
Arab Science Heritage Journal
آل البيت ( عليهم السلام ) من خلال كتاب درر السمط في خبر السبط لابن الابار البلنسي الاندلسي ( ت658هـ/1260م)
...Show More Authors

One of them one of the important books due to its containing valuable information written by the author. Information include the life of the Messenger (Peace be upon him) before and during the mission and what happened to the messenger and his adherents and faithful companions (May Allah be pleased with them all)

View Publication Preview PDF
Crossref
Publication Date
Mon Jan 05 2026
Journal Name
مجلة الجامعة العراقية
معضلة "الإجماع" في ميثاق جامعة الدول العربية وأثرها على إدارة أزمة الخليج الثانية (1990-1991): قراءة قانونية-تاريخية
...Show More Authors

الملخص (باللغة العربية) شكّل اجتياح العراق للكويت في 2 آب/أغسطس 1990 اختباراً حاسماً لقدرة جامعة الدول العربية على إدارة الأزمات الإقليمية وصياغة موقف عربي موحّد إزاء انتهاك واضح لسيادة دولة عضو. غير أن أداء الجامعة خلال أزمة الخليج الثانية كشف عن حالة من الشلل المؤسسي والإجرائي، تجلّت في بطء اتخاذ القرار، وتنازع التأويلات حول شرعية الإجراءات، وتوظيف نصوص الميثاق بما أعاق إنتاج قرار عربي حازم وقابل للتنفيذ. تن

... Show More
View Publication Preview PDF
Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Design and Comparative Study of a one and Two Stage Blumlein Circuit TEA Nitrogen Laser
...Show More Authors

Two Prototypes of Transversely Excited at atmospheric pressure (TEA) Nitrogen laser systems (One Stage Blumlein Circuit and Two Stage Blumlein Circuit) were fabricated and operated. High voltage power supply with variable operating voltage (0-20 kv) and operating current (1-3A) was built and tested successfully. The gas flow rate of 15 L/ min and 10 L/ min for OSBC and TSBC was used. The performance of the fabricated systems was studied extensively reaching to the optimum operating conditions. The obtained laser output energy for the first system has linear relationship with the applied voltage. The maximum output energy was about (1.14 mJ) with (10.40) ns pulse duration and the half-wave divergence angle was about (0.1455 m rad). In the

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Medical service quality, Dimensions the quality of service, satisfaction with medical service
...Show More Authors

 

 the Objective of  study is  to measure the quality of medical service level,  in the  Iraq public hospitals ,presented by  special words ,private hospitals, and compare between them, by knowing the level of recipients satisfaction  of medical service for all dimensions of quality service, and then measuring satisfaction with the quality of medical service as a whole for both of them, which have been prepared in questionnaire form, included two main directions, first to determine the level of satisfaction when, recipients of medical service is not dimensions quality of service in accordance with the Scale Servqual by (Parasurman et .al 1988), consisting of five di

... Show More
View Publication Preview PDF
Crossref