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Experimental Study on Double-Pass Solar Air Heater with and without using Phase Change Material
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In this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant air mass flow rate of (0.0375 kg/sec). The parameters that affect the thermal performance of the SAH with and without the PCMs presented by solar radiation, the difference in air temperature, outlet air temperature, instantaneous thermal efficiency, and daily efficiency are evaluated. The experimental results show that when using the PCM, the temperature of the outlet air was enhanced and increased over the ambient temperature by (1.5 - 6.5 C) after sunset for 5 hours period. It was found that the instantaneous thermal efficiency of the heater using thermal storage exceeds 100% after sunset, this is due to a large amount of heat stored in the paraffin wax that has been released during the discharge process. Also, it was found that the daily efficiency of the double pass SAH integrated with and without thermal energy storage unit was (56, 47%) respectively.

 

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Publication Date
Fri Dec 01 2023
Journal Name
Political Sciences Journal
The Future of the Russian- Ukrainian War and the Extent of its Reflection on the Security of Eastern European Countries after 2022
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Wars represent one of the most serious threats to the world order; It is considered a violation of international laws and norms, and humanitarian principles. From this point comes the study of the importance of the topic entitled (The Future of the Russian-Ukrainian war and the extent of its Reflection on the security of Eastern European countries after the year 2022). This study is based on reviewing future possibilities (scenarios) of war. The Russian-Ukrainian war, which was launched by the Russian government led by Russian President Vladimir Putin in February 2022, is still ongoing at the time of writing this research. This chapter includes three possibilities (scenarios). The first possibility deals with the development of the war t

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Publication Date
Tue Sep 17 2019
Journal Name
Journal Of The College Of Education For Women
The Architectural Heritage of Baghdad in Ibn Al-Faqih Hamadani's Book Baghdad the City of Peace And its impact on Sustainable Development
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This research shows the importance of Baghdad in the field of urban heritage and was demonstrated in the Ibn al-Fiqh al-Hamdani's book Baghdad the City of Peace in which he focused on many urban aspects and reviewing its historical importance by connecting them with modern events and the role they play in cultural and civilized construction which included: mosques, schools and markets etc. and the service providing institutions and other pillars of the Islamic cities through showing the development back then and its importance as an integral part of the urban and cultural heritage of the Islamic cities in general and Baghdad city in particular. 

In his book Baghdad the City of Peace, Ibn al-Faqih Hamadhaani

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Publication Date
Tue Dec 05 2023
Journal Name
Baghdad Science Journal
Synthesis of Multifunctional Polymers Based on Tert-Butyl Acrylamide/Octyl Acrylate as Lubricant Additives and Adsorbents for Copper Ion from Aqueous Solution
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Two homopolymeric and three copolymeric additives for base oil were synthesized using octyl acrylate (OA) and tert-butyl acrylamide (TBA) monomers. The two additives named P1 and P2 are the homopolymers of TBA and OA, respectively, whereas copolymeric additives named Co1, Co2, and Co3 were synthesized by varying the ratios of TBA:OA as 1:3, 3:1 and 1:1, respectively. The prepared polymers were characterized by Fourier Transform Infrared (FTIR). Based on the solubility of synthesized polymers in base oil and reactivity ratios of TBA/OA copolymer (0.222, 0.434) calculated by Fineman-Ross method, P2, Co1, Co2 and Co3 were selected to evaluate their performance as pour point depressant (PPD), viscosity improver (VII), and anticorrosion addit

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Publication Date
Wed Jun 01 2016
Journal Name
Journal Of Engineering
The Effects of Inclination and Compounds Angles of Round Holes in Staggered Rows on Adiabatic Film Cooling Effectiveness of Vane Suction side
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The aim of this work is oriented to increase film cooling effectiveness value through numerical investigations for flow of Mach number not more than 0.3 around vane surface, to find the effects of inclination and compounds angles of round holes in staggered rows on adiabatic film cooling effectiveness of vane suction side. Multi cylindrical film cooling hole cases were studied with pitch ratio P/d =2 and 3, local blowing ratios M=0.382, 0.77 and 1.14,  inclination angles a=30° and 45°, compound angles β= 0°, 15°, 30° and 45° and local momentum ratios I= 0.084, 0.34 and 0.756  for better cooling process.

            A numerica

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Publication Date
Sun Jan 21 2024
Journal Name
Biomedicine
Detection of the effect of synthetic siRNA on efflux pump MexA gene expression and antibiotic resistance in clinical isolates of Pseudomonas aeruginosa
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Introduction and Aim: Pseudomonas aeruginosa is a nosocomial infection with an ability to develop high levels of antibiotic resistance. The efflux pump system is one of the mechanisms that is linked to multidrug resistance in P. aeruginosa. In this study, we employed siRNA loaded on gold nanoparticles against the MexA efflux pump gene to decrease the MexA gene expression in P. aeruginosa and estimated antibiotic resistance after gene silencing.   Materials and Methods: This study examined four strains of P. aeruginosa isolated from patients in various hospitals in Baghdad. Bacteria isolated were identified by biochemical tests and Vitek compact 2 system.  Single-stranded siRNA (33bp) designed in this study was loaded onto gold

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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
The effect of usage two methods of garlic extraction( foliar and ground application) on the growth of the tomatoes (Solanum lycopersicum) plant
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Abstract<p>Garlic is rich in nutritional and medicinal value as it has been found that the water extract of garlic plant contains 31% carbohydrates and rich in elements calcium, phosphorus, magnesium, potassium, sodium, iron, zinc, manganese, vitamin C, thiamine, riboflavin, niacin and pyridoxine. The aim of this study was to investigate the effect of garlic extract (<italic>Allium sativum</italic> L.) on tomatoes (<italic>Solanum lycopersicum</italic> L.) plant. The trend is to use plant extracts in foliar and ground fertilization. Three levels of foliar application (4, 6, 8%), three levels of ground application (10, 20, 40%), one treatment 6% of foliar and 20% ground applic</p> ... Show More
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Publication Date
Thu Feb 19 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of different palatal vault shapes and woven glass fiber reinforcement on dimensional stability of high impact acrylic denture base [part II]
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Background: Change in palatal vault shape and Reinforcement of high impact acrylic denture base resin may in turn affect the dimensional accuracy of acrylic resin and affecting the fitness of the denture. The aim of study is to evaluate the effect of fiber reinforcement for high-impact acrylic resin denture base with different palatal vault shapes on linear dimensional change and effect of palatal vault shapes on linear dimensional changes of non-reinforced and fiber reinforced high impact denture base acrylic resin Material and method: Three different palatal vault shapes were prepared on standard casts using CNC (computer numerical control) machine. 60 samples of heat polymerized high impact acrylic resin maxillary denture base were fabri

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Publication Date
Tue Feb 12 2019
Journal Name
Iraqi Journal Of Physics
Effect of laser energy and ablation time on the formation of aluminum nanoparticles by nanosecond laser ablation of aluminum target in ethanol
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In this work we study the influence of the laser pulse energy and ablation time on the aluminum nanoparticles productivity during nanosecond laser ablation of bulk aluminum immersed in liquid.
Aluminum nanoparticles were synthesized by pulsed laser ablation of Al targets in ethanol for 3-8 minutes using the 1064 nm wavelength of a Nd:YAG laser with energies of 300-500 mJ per pulse.The laser energy was varied between 300 and 500 mJ/pulse, whereas the ablation time was set to 5 minutes. UV-Visible absorption spectra was used for the characterization and comparison of products.

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Publication Date
Thu Aug 01 2013
Journal Name
Journal Of The College Of Basic Education
A laboratory assessment on the effect of powder from Foeniculum vulgare and Eruca sativa against saw-toothed grain beetle Oryzaephilus surinamensis (L.)
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Publication Date
Tue Feb 14 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of Teaching Practices of Science and Mathematics Teachers Based on the National Framework for Future Skills in the Omani School
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Abstract

The research aims to identify the level of effectiveness of the teaching practices of science and mathematics teachers in light of the national framework for future skills in Omani schools. To achieve the objectives of the study, the researchers used the descriptive approach, as he designed a note card consisting of (30) phrases distributed on three axes: basic skills, practical skills, and technical skills. After verifying the validity and reliability of the tools, they were applied to a sample of (116) teachers. The results of the research revealed that the level of effectiveness of the teaching practices of mathematics teachers has recorded a medium degree with a mean (3.05). The results a

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