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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
Sat Oct 01 2022
Journal Name
Inorganic Chemistry Communications
Investigation of performance and efficiency of donor-π-bridge-acceptor based material solar cell
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The novel groups of organic chromophores containing triphenylamine (TPA) (ATP-I to ATP-IV) have been constructed by structural modification of electron donors with substitution biphenyl and bipyridine rings inserting a π-linkage. Density functional theory (DFT) and time-dependent type of it (TD-DFT) have been operated to study results of donating ability of TPA and spacer on absorption, geometrical, photovoltaic, and energetic attributes of these sensitizers. Structural attributes have been revealed that incorporation of TPA, acceptor and π bridge include a perfect coplanar conformation in TPA-III. Based on frequency computations and ground-state optimization, bandgap (Eg) energy, ELUMO, EHOMO have been determined. For enlightening maximu

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Publication Date
Sun Sep 27 2020
Journal Name
Journal Of The College Of Education For Women
Imagination and Emotional Impact by Constructional Methods:Al-Almohdeen’s (Believers’) Poetry in AhlAl-Bayt, (peace be upon them) as a Model
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The language that consists of only twenty-eight letters, but it is so broad that we are unable to understand it from all sides and this expansion is mainly caused by imagination, so Arab imagination, whose language goes in all directions And as it always responds to our ears, ancient critics divide imagination into holistic and partial But the language is not limited to these parts only. Do we wonder, where is the structural method of wishing, hope, questions and other methods of all this? In this paper, we try to show the importance of the method of writing in moving imagination in an interactive way, and what is related to human feelings in most, if not all, of its methods By studying the poetry of the believers in the Ahl al-Bayt, pea

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Study the Factors Effecting on Welding Joint of Dissimilar Metals
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The aim of this work is to study the factors that affect the welding joint of dissimilar metals. Austenitic stainless steel-type AISI (316L) with a thickness of (2mm) was welded to carbon steel (1mm) using an MIG spot welding.  The filler metal is a welding wire of the type E80S-G (according to AWS) is used with (1.2mm) diameter and CO2 is used as shielding gas with flow rate (7L/min) for all times was used in this work.

        The results indicate that the increase of the welding current tends to increase the size of spot weld, and also increases the sheer force.  Whereas the sheer force increased inversely with the time of welding. Furthermore, the results indicate that i

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Publication Date
Sun Jan 01 2023
Journal Name
Aip Conference Proceedings
Using the artificial TABU algorithm to estimate the semi-parametric regression function with measurement errors
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Artificial Intelligence Algorithms have been used in recent years in many scientific fields. We suggest employing artificial TABU algorithm to find the best estimate of the semi-parametric regression function with measurement errors in the explanatory variables and the dependent variable, where measurement errors appear frequently in fields such as sport, chemistry, biological sciences, medicine, and epidemiological studies, rather than an exact measurement.

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Publication Date
Sun Dec 15 2019
Journal Name
Journal Of Global Pharma Technology
synthesis and characterization of heterocyclic compounds and polymers with studying the biological activity for some of them
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This paper deals with the preparation of new monomers and polymers which including heterocyclic unit. The diacid chlorides compounds [1-3] were prepared from the reaction of glutaric acid, adipic acid, terephthalic acid with thionyl chloride. Succinic acid reacted with ethanol to produce compound [4]. Compound [4] reacted with hydrazine hydrate to obtain succinic hydrazide [5].Compound [5] reaction with CS2 and KOH in absolute ethanol to produce compound [6].The polymers [7-12] have been created by reacting diacid chlorides compounds [1-3] with compound[5] or [6] in dry pyridine with some drops of DMF. The topology of produced compounds has characterized through their spectral and analytical data as in FT-IR spectra, Thermal analysis [DSC,

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Publication Date
Wed May 01 2024
Journal Name
Journal Of Madenat Alelem College
Study 1,4- Naphthoquinone Derivative and Biological Activity: A Review
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In this work, we focused on studying 1,4-naphthoquinones and their derivatives, and knowing the methods of preparing them using different auxiliary agents and forming derivatives containing heterocyclic rings, active groups and saturated rings containing heterogeneous elements . In addition, due to their strong antibacterial, antifungal and anticancer activity, 1,4-naphthoquinone compounds biological importance and are considered a source of various pharmaceutical compounds.

Publication Date
Fri Nov 03 2023
Journal Name
Lecture Notes In Electrical Engineering
A Survey Study and Comparison of Drones Communication Systems
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Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
Negative skin friction evaluation and mitigation: A review study
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Publication Date
Thu Jun 01 2023
Journal Name
Journal Of Composite Materials
Fabrication and characterization of bioactive composite: A pilot study
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The increasing requirement and use of dental implant treatments has rendered dental implantology indispensable in dentistry. The aim of this study is to determine the optimum concentration of calcium silicate to be incorporated into a polyetherketoneketone (PEKK) matrix used as an implant material to enhance the bioactivity and mechanical properties of the composite compared with unmodified PEKK. In this study, different weight percentage (wt%) of micro-calcium silicate (m-CS) is incorporated into PEKK with ethanol as a binder. Subsequently, the mixture is dried in a forced convection oven at 120°C and poured into customized molds to fabricate a bioactive composite via compression molding (310°C, 15 MPa, and 20 min holding time

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Impact of empowerment and functional flexibility in evaluating worker performance :an empirical study
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This study was conducted in the Department of Employment and Loans at the Ministry of Labor and Social Affairs to indicate the importance and impact of both the empowerment and the functional flexibility in evaluating the performance of the employees. To achieve the objectives of the study, the data was collected through a questionnaire form designed for this purpose based on previous studies. Data obtained for a significant evaluation of the relationship between the components of both the empowerment and the functional flexibility with the components of the evaluation and determining the degree of importance of each component of both the empowerment and functional flexibility for the components of the evaluation by the extractio

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