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Experimental Study Using the Passive Solar Chimney for Evaporative Cooling With PCM and CFM as a Thermal Energy Storage
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      In this work, a test room was built in Baghdad city, with (2*1.5*1.5) m3  in dimensions, while the solar chimneys (SC) were designed with aspect ratio (ar) bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB) that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled  in the bottom of TESB of vertical SC. The TESB was made from metallic iron sheets as a shell and fuelled by paraffin wax as phase change material (PCM). The PCM supported by copper foam matrix (CFM) to enhance thermal conductivity of wax. When heat is released from TESB to the air, a buoyancy force will be generated in chimney gaps. Then a difference in pressure between inside and outside test room leads to induce the air flow to test room through wet corrugated cellulose pad, where evaporative cooling (EC) occurs. Results of experimental work, that achieved in June, for 12 to24 hour in the test day, refer to effectiveness using EC to decrease the room temperature comparing. The system reduces test room temperature of up to 8.5~9.2 oC in 11:00 am to 3:00 pm and at highest effectiveness of EC, while minimum reduces in temperature of up to 3.5 oC in 8:00pm to 3:00 am. Also, the results showed the affectivity to using the TESB, during the night time for ventilation and EC, with lower effectiveness than from day time. The range of EC effectiveness equals 30.5-37.5 with a natural vent, while The maximum air change per hour (ACH) equals (3.8-6.187), and the maximum mass flow rate is equal to (36.651 kg.hr-1) at experimental evaluation of the system’s discharge coefficient value 0.371.

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Publication Date
Sun Mar 26 2023
Journal Name
Arab Science Heritage Journal
أمراء البحر في العصر العباسي إلى نهاية القرن الثالث الهجري/ التاسع الميلادي
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The Abbasid state inherited many enemies because of the Islamic conquests in the Umayyad era and its geographical extension, which included a number of seas, so it had to direct its energy to preserve the achievements achieved by its predecessors from the Muslims. One of the sea princes who had a role in protecting the coasts of the Abbasid state, especially in the Levant and Egypt.

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Publication Date
Sun Nov 04 2018
Journal Name
Arab Science Heritage Journal
اسهامات إسهامات المقادسة العلمية في مصر من القرن (5-8هـ/ 11-14م)
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The Subject  of  contritutions  to Jerusalemites  Scientific  in  Egypt  from  8.5  Century  14.11 AD of  noteworthy  studies  Concern  Coming  Of these  Scientists  to  Egypt  has  helped  toth  to  Seek  Knowledge  and  Study  or  teaching  in  the tooming  w0rid of Science  broadly  and  distinctive  through  Scientific  interaction  and  intermingling  of  Civilization  between  Scientists  this  Mixing  effect  of  the  Scientific  life  and  in tellectal  of The  nam

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Publication Date
Fri Feb 08 2019
Journal Name
Journal Of The College Of Education For Women
مدى معرفة المرأة بمعلومات البطاقة الارشادیة المرفقة بالملابس والمفروشات في مدینة بغداد
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It takes a long time and a lot of money to choose and provide clothes. It is soothing
necessary to care of them in order to use it another time. There is no Disposable clothes
until now, like other things in the house which we used for once then we dropped, then we
can use new one without any time or effort can be mentioned like needles, nappy, tissues
and etc.
The clothes are different; people should take care of and clean them again in order to
use them again. The right care of clothes would make them last for a long time. So, there is
no need to buy a new one instead of them in a short time. This thing provides time and
effort for the people and the family, to affect positively on the family’s budget.
We s

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Publication Date
Fri Jan 04 2019
Journal Name
Journal Of Planner And Development
أثر التوجيه بتأثيرأشعة الشمس على التطور العمراني للشوارع التجارية في مدينة بغداد
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Publication Date
Sun May 10 2015
Journal Name
Al-academy
Symbol Significances in Fakhir Mohammad Paintings 1980 - 2010: إيناس مهدي ابراهيم الصفار
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Address the current research study " Symbol Significances in Fakhir Mohammad Paintings " in an attempt to detect signs of the icon in the artist's fee . The research contains four chapters The first chapter of which the methodological framework for the search starting with the problem of the specific research and asking the following: Maaltold semantic code in fees Luxury Muhammad? As well as displaying the importance of research and the need for it and in order to search through ( you know the implications of the code in the fee Luxury Muhammad) and for the period of ( 1980-2010 ) in his works of art as well as identifying the search terms . In the second chapter , such as the theoretical framework , and contained three sections focus o

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Crossref
Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
Problems Facing University Students in Distance Learning
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The current study aims to examine the level of problems faced by university students in distance learning, in addition to identify the differences in these problems in terms of the availability of internet services, gender, college, GPA, interactions, academic cohort, and family economic status. The study sample consisted of (3172) students (57.3% females). The researchers developed a questionnaire with (32) items to measure distance learning problems in four areas: Psychological (9 items), academic (10 items), technological (7 items), and study environment (6 items). The responses are scored on a (5) point Likert Scale ranging from 1 (strongly disagree) to 5 (strongly agree). Means, standard deviations, and Multivariate Analysis of Vari

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Publication Date
Sat Jun 01 2013
Journal Name
الاستاذ
الآخر في الشعر العربي الحديث (من نكسة حزيران إلى أخريات الألفية الثانية)
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الآخر في الشعر العربي الحديث (من نكسة حزيران إلى أخريات الألفية الثانية)

Publication Date
Sun Dec 01 2013
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Obstacles in Marketing Comprehensive Automobile Insurance Policy: بحث أستطلاعي في شركة التأمين الوطنية
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Comprehensive automobile insurance is considered as an important branches in the portfolio of National Insurance Company in Iraq .Due to the continous accidents the company is endeavouring to   this market.

    The company faces several obstacles and limitations in marketing the policies of this portfolio due to certain factors and influences beyond the control of the company and others internal mainly connected with the reduction of the marketing programmes of the company .

    The target of this study is  to focus the light  upon the interal factors which can be gorerned by the company,confronted and solved.

 

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Publication Date
Sat Jan 05 2019
Journal Name
Journal Of Planner And Development
التوجه التصميمي وأثره في تعريف نقطة الحد الاقتصادي لكلفة بناء الوحدة السكنية
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Publication Date
Sat Dec 01 2018
Journal Name
Al-khwarizmi Engineering Journal
Time Series Analysis of Total Suspended Solids Concentrations in Euphrates River in Al-Nasria Province
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The monthly time series of the Total Suspended Solids (TSS) concentrations in Euphrates River at Nasria was analyzed as a time series. The data used for the analysis was the monthly series during (1977-2000).

The series was tested for nonhomogenity and found to be nonhomogeneous. A significant positive jump was observed after 1988. This nonhomogenity was removed using a method suggested by Yevichevich (7). The homogeneous series was then normalized using Box and Cox (2) transformation. The periodic component of the series was fitted using harmonic analyses, and removed from the series to obtain the dependent stochastic component. This component was then modeled using first order autoregressive model (Markovian chain). The above a

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