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An Experimental Study of the Effect of Vortex Shedding on Solar Collector Performance
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In this work, the effect of vortex shedding on the solar collector performance of the parabolic trough solar collector (PTSC) was estimated experimentally. The effect of structure oscillations due to wind vortex shedding on solar collector performance degradation was estimated. The performance of PTSC is evaluated by using the useful heat gain and the thermal instantaneous efficiency. Experimental work to simulate the vortex shedding excitation was done. The useful heat gain and the thermal efficiency of the parabolic trough collector were calculated from experimental measurements with and without vortex loading. The prototype of the collector was fabricated for this purpose. The effect of vortex shedding at different operation conditions was examined. The variation of angles of attack and wind velocity leads to different values of vortex loading coefficients and shedding frequencies. The relation between the dynamic characteristics and solar collector performance was evaluated. The finite element method was used to estimate the dynamic characteristic of the solar collector in addition to experimental work to evaluate the relation between the dynamic behavior of the collector and its performance.

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Publication Date
Tue Jun 30 2020
Journal Name
Kuwait International Law School Journal
The Duration of the Contract – A Study in Light of French Decree No. 131-2016 Issued on February 10, 2016
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After the Napoleonic Code of 1804 came without any legal rules specific to the duration of the contract, and was content to refer to it in scattered legal texts, Legislative Decree No. 2016-131 came to establish a comprehensive legal system for the duration of the contract, starting from the period of its formation, through the period of its implementation, and ending with its continuation after the expiration of its term, in the third section of the fourth chapter related to the effects of the contract (Articles 1210 - 1215), relying on judicial precedents on the one hand - which are many, as will be shown through the research pages - and contractual practices on the other hand. Perhaps the main motive that prompted the French legislator t

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Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
Effect of Sn Addition on Phase Transformation Behavior of Equiatomic Ni-Ti Shape Memory Alloy
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Sn effect on the phase transformation behavior, microstructure, and micro hardness of equiatomic Ni-Ti shape memory alloy was studied. NiTi and NiTiSn alloys were produced using vacuum induction melting process with alloys composition (50% at. Ni, 50% at.Ti) and (Ni 48% at., Ti 50% at., Sn 2% at.). The characteristics of both alloys were investigated by utilizing Differential Scanning Calorimetry, X- ray Diffraction Analysis, Scanning Electron Microscope, optical microscope and vicker's micro hardness test. The results showed that adding Sn element leads to decrease the phase transformation temperatures evidently. Both alloy samples contain NiTi matrix phase and Ti2Ni secondary phase, but the Ti2Ni phase content dec

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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Entrepreneurial performance in accordance with the competitive intelligence and strategic
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 The research aims to study the entrepreneurial performance of the banks, according to the intelligence of competitive and strategic as the entrepreneurial performance is the one who does not stand the benefits of excellence in accomplished when just achieving the bank's objectives planned, but exceed it down to creativity in accomplishing these goals in a manner leads to making a entrepreneurial bank in the markets and the focus the eyes of competitors and the banks and other Following his example.

Was chosen the subject of research and strategic intelligence and competitive because of its impact on the strategic success of the banking sector, the fact is the entrepreneurial in the Iraqi banking mar

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Publication Date
Tue Aug 15 2023
Journal Name
Al-academy
Effect of partial substitution of alkaline oxides with lithium oxide (Li2O) on low-temperature ceramic glaze
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The research aims to study the effect of adding (Li2O) to an alkaline glaze containing (K2O, Na2O). Although all the alkaline oxides have common properties, each oxide has something that distinguishes it. The molecular weight of (Li2O) is two times less than that of (Na2O) and three times that of (K2O). Therefore, it is added in small proportions. In addition, it is a very strong flux, so it is not used alone, but rather replaces a part of other alkaline oxides. It was added to an alkali glass that matured at a temperature of 980CO in proportions (2.0,1.4,1.2,0.8,0.4%) instead of (Na2O), using lithium carbonate (Li2CO3) as an oxide source. The glazes mixtures were applied to a white pottery body, and the samples were fired and cooled acc

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Publication Date
Sat Oct 28 2023
Journal Name
Baghdad Science Journal
Lead acetate deteriorates the improvement effect of L-arginine and tetrahydrobiopterin on endothelin-1 receptors activity in rat aorta
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Endothelin-1 (ET-1) is a potent vasoconstrictor hormone that has been identified as an important factor
responsible for the development of cardiovascular dysfunctions. ET-1 exerts its vasoconstrictor activity
through two pharmacologically distinct receptors, ETA and ETB that are found in vascular smooth muscle
cells (VSMCs) and the vasodilator activity through an ETB receptor located on endothelial cells. This study
aimed to show the impact of 1µM L-arginine (LA), 100µM tetrahydrobiopterin (BH4), and their combined
effect on ET-1 activity in both lead-treated and lead-untreated rat aortic rings. This means, investigating how
endothelial dysfunction reverses the role of nitric oxide precursor and cofa

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Publication Date
Fri May 15 2009
Journal Name
Journal Of Planner And Development
Preservation of heritage markets within an integrated framework to preserve the urban heritage in the historical centers of cities (selected models and experiments)
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This research discusses the rehabilitation of heritage markets in the historical centers of Islamic Arab cities and their use in the field of cultural tourism as one of the most important tourist attractions and the subsequent revival of the national economy in addition to preserving the urban heritage as these markets part of the historical centers of cities. The research also discusses the preservation of the continuity of heritage markets as a product of cultural heritage value within an integrated framework to preserve the urban heritage in the historic centers of cities. The study then reviews a number of experiences of Arab and Islamic countries in the field of preserving and rehabilitating heritage markets, which qualify them to b

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Publication Date
Sat Sep 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Environmental Taxes Effectiveness on controlling The Pollution reduction levels due To the Activity Contracted Foreign Oil Companies in Iraq: An applied research in the general commission of taxes
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     Environmental Tax is deemed as one of the most important tools that can be used to eliminate the problem of oil –based  environment pollution resulted out of oil products processes and this has been significantly approved by the experience in those leading countries in the field of protecting the environment against pollution whereas oil-producing countries which are rather awkward in maintaining the environment such as Iraq , suffer from notorious environmental effects pertaining to oil product processes.

     The problem of the research is represented the increased and constant rise in the volume of the environmental pollutants resulted from the processes managed by the intern

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Publication Date
Thu Dec 01 2022
Journal Name
Case Studies In Construction Materials
Push-out test of waste sawdust-based steel-concrete – Steel composite sections: Experimental and environmental study
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Publication Date
Fri Jun 01 2018
Journal Name
Journal Of Engineering
Experimental Study of Optimum Chilled Water Distribution Configuration in Air Conditioning Terminal Unit Using RSM Technique
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The distribution of chilled water flow rate in terminal unit is an important factor used to evaluate the performance of central air conditioning unit. A prototype of A/C unit has been made, which contains three terminal units with a complete set of accessories (3-way valve, 2-way valve, and sensors) to study the effect of the main parameters, such as total water flow rate and chilled water supply temperature with variable valve opening. In this work, 40 tests were carried out. These tests were in two groups, 20 test for 3-way valve case and 20 test for 2-way valve case. These tests were performed at three levels of valve opening, total water flow rate and water supply temperature according to the design matrices establis

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Publication Date
Thu Dec 01 2022
Journal Name
Case Studies In Construction Materials
Push-out test of waste sawdust-based steel-concrete – Steel composite sections: Experimental and environmental study
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