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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
Mon Aug 07 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Purification of Fungul Glucoamylase and Study the Effect of Concentration And Thermal Processing on Enzymatic Activity of Starch Hydrolysis
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Glucoamylase from black Aspergillus niger isolate was purified by ammonium sulfate precipitation and sephadex G 200 filtration. A trial for the purification of glucoamylase resulted in an enzyme with a specific activity of 6472 unit/mg protein with 10 times fold. The main goal of the present work was to test this enzyme in hydrolyzing the raw starch. Two substrates were used: corn starch and potato starch 2% (w/v). The effect of enzyme dosage and thermal processing of substrate on kinetics and efficiency of hydrolysis were studied. The results suggested that the glucoamylase activity is increased as the increase of enzyme concentration and the enzyme was sufficiently effective in hydrolyzing tested raw starch, and thermal modification of

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Computational Design And Engineering
CFD analysis of phase-change material-based heat storage with dimple-shaped fins: evaluation of fin configuration and distribution pattern
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Abstract<p>Phase-change materials (PCMs) have a remarkable potential for use as efficient energy storage means. However, their poor response rates during energy storage and retrieval modes require the use of heat transfer enhancers to combat these limitations. This research marks the first attempt to explore the potential of dimple-shaped fins for the enhancement of PCM thermal response in a shell-and-tube casing. Fin arrays with different dimensions and diverse distribution patterns were designed and studied to assess the effect of modifying the fin geometric parameters and distribution patterns in various spatial zones of the physical domain. The results indicate that increasing the number of </p> ... Show More
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Publication Date
Sun Dec 01 2019
Journal Name
Baghdad Science Journal
Histological and Physiological Studies on the Long-term Effect of Different Concentrations of Energy Drink (Tiger) on the Renal and Hepatic Systems of Young Mice
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The present study aims to investigate the long-term histopathological, and physiological effects of different concentrations of a commercially available energy drink (Tiger) on liver and kidney of young mice. Sixteen Balb/c male mice,6 -week old, were divided into 4 groups (n=4). Two groups consumed the energy drink at a concentration of 28µl energy drink/ml water. One group were killed after 10 days (T1), another group were killed after 20 days (T2). Other group of mice consumed the energy drink at a final concentration of 14µl/ml for 20 days (T3). The last group was provided only with water and served as control. Mice of all groups drank around 3 ml per day. The histopathological study on liver of treated groups showed many changes s

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Publication Date
Sun Jan 01 2012
Journal Name
كلية التربية-الجامعة المستنصرية
Study the diffusion of Hydrogen in metals using a Runge-Kutta method
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Publication Date
Mon May 20 2019
Journal Name
The Journal Of Engineering
Experimental comparison of two linear machines developed for the free piston engine
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: In this study, a linear synchronous machine is compared with a linear transverse flux machine. Both machines have been designed and built with the intention of being used as the power take off in a free piston engine. As both topologies are cylindrical, it is not possible to construct either using just flat laminations and so alternative methods are described and demonstrated. Despite the difference in topology and specification, the machines are compared on a common base in terms of rated force and suitability for use as a generator. Experience gained during the manufacture of two prototypes is described.

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Planner And Development
The "actor network theory" approach in dealing with landscapes in historical centers
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The historical center's landscape suffers from neglect, despite their importance and broad capabilities in enhancing the cultural value of the historical center, as landscape includes many heterogeneous human and non-human components, material and immaterial, natural and manufactured, also different historical layers, ancient, modern and contemporary. Due to the difference in these components and layers, it has become difficult for the designer to deal with it. Therefore, the research was directed by following a methodology of actor-network theory as it deals with such a complex system and concerned with an advanced method to connect the various components of considering landscape as a ground that can include various elements and deal wi

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Publication Date
Fri Oct 02 2020
Journal Name
Biochemical & Cellular Archives
Retinoids and rexinoids as vitamin A analogs.
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Vitamin A, namely retinol is still the most proper agent for modulating so many biochemical reactions and biological functions in different tissues and organs. In addition to the provitamins A and α, βand γ-carotenoids that are present in various foods from either animal or plant origin, retinoids and rexinoids form the natural and synthetic analogs that are chemically related or unrelated and can be added as food supplements for deficiency disorders of vitamin A or used to alleviate or treat certain health problems such as skin carcinoma, acne, skin aging and dermatitis.

Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
The Romantic Nightingale between Coleridge’s Divergence and Keats’ Adherence: A comparative Study between Coleridge’s ‘The Nightingale’ and Keats’ ‘Ode to a Nightingale’
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‘Ode to a Nightingale’(1819) is a typical poem of a Romantic poet like John Keats, but
‘The Nightingale’(1798) is an uncharacteristic poem of a Romantic poet like Coleridge.
The paper proposes a comparison between Coleridge’s ‘The Nightingale’ and Keats’
‘Ode to a Nightingale’.Coleridge’s poem diverges from the Romantic norm; it carries some
characteristics new to Romantic poetry like the realistic and objective portrayals of nature and
the nightingale, while Keats’ poem adhere to the characteristics of Romantic poetry; it
portrays nature and the nightingale subjectively and unrealistically. Coleridge’s poem is very
much influenced by the scientific approaches to environment, and natural his

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Determinants of Total Factor Productivity Growth: an Analytical Study of a Cross Section of Countries for the Period (2003-2016)
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            This study tests the effect of a large number of independent variables that control the growth of the total productivity, which amounted to 112 variables, gathered from what is mentioned in the specialized theoretical and applied literature. The data for these variables were taken from global reports of sound international organizations and reliable databases covering the period 1991-2016. The data of the dependent variable, the growth of the total factor productivity, were taken from the database of the world development indicators. The study covered 61 countries for which data were available. The study included three regression models to explain

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Publication Date
Sun Jun 30 2013
Journal Name
College Of Islamic Sciences
Ruling on dealing with Jews in Muslim countries
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Praise be to God, who is satisfied with Islam as our religion, “He opened a clear conquest for us,” and whoever works with us through the Shari’ah works and protects us. And that our master and Mawlana Muhammad His servant and Messenger is a prophet who has been merciful and compassionate. "
And after:
The occupation of Iraq and the accompanying bone events, and the following severe obstacles, resulted in a set of problems that require legitimate stances, and satisfactory answers, remove confusion and delusion, amid the clash of opinions and contradictions of jurisprudence. Work and application.
Among the difficult problems that surfaced in light of the new political developments on the land of Iraq: (the ruling on dealing

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