The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o) are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.
Ismailism is of great importance in Islamic history and Islamic political thought. In different countries of the Muslim world today their presence exists and is active but is confused with mystery and secrecy. The most important characteristic of their political ideology is their dependence on the esoteric exegesis, which they have made an intellectual basis for which their most ideas relate, when they make for everything visible and exposed a hidden matter, not only aware of the esoteric exegesis, which only God knows and entrenched in science, and they mean imams or whoever They are called "(esoteric)" as a result of the Ismaili belief in esoteric interpretation and that everything is apparent inward, as well as they called the ((seven
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A total of 722 algal taxa are recorded in Diyala River by different authors. Most of the identification algae belong to three Divisions: Bacillariophyceae (367, 50.8%), Chlorophyceae (179, 24.8%), and Cyanophyceae (126, 17.5%).
Time and space are indispensable basics in cinematic art. They contain the characters, their actions and the nature of events, as well as their expressive abilities to express many ideas and information. However, the process of collecting space and time in one term is space-time, and it is one of Einstein’s theoretical propositions, who sees that Time is an added dimension within the place, so the study here differs from the previous one, and this is what the researcher determined in the topic of his research, which was titled (The Dramatic Function of Space-Time Variables in the Narrative Film), Which included the following: The research problem, which crystallized in the following question: What is the dramatic function of the tempor
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Human values are the most important concepts that the interest of society has to relay on these conceptual values. Any society will not be stabilized unless adheres to the right principles and values, all nations need such principles and values to stabilize. If any society doesn’t implement the human values that monotheistic religions urges equality between human, the far the society from the religious principles, the less there would be valence between human. The valence is urgent necessity in the current time. The far people get away from values and principles, the more they lose their freedom and dignity, therefore individual has to live with dignity and respect through the adherence to these values and principles. Apparently, equal
... Show Morethe current study Included, evaluation the impact of Nitrofurantoin drug on liver in albino mice, 128 male albino mice have been used . Animals treared with (150,200 Mg/Kg) for 8 weeks . NFI caused histological changes in liver represented by , swelling of hepatocytes, disappearance of radial arrangement , vaculation of liver cells , increasing of kupffer cells and appearance of giant cells. NFT caused Congestion of blood vessels and infiltration of inflammatory cells in liver in all used concentrations.
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The indicators were important core for any work, and may be occurring this indicators way of communicating among planers and decision makers, even also for public participating, do make any decision. The urban and regional planning is one of those science highly depending on using indictors, for two reasons, first, way to communicating ideas between specialist and non-specialist, (politician and decision makers), the second one, this field are multidisciplinary science, so the need indictors to clearing thoughts among different backgrounds in one team, as common language.
This research tries to clear importance of GIS in forming and building Spatial Planning Indicators, to cross communication problem among planning g
... Show MoreAjloun reserve is the most important reserved areas set up by the Jordanian government to encourage development and ecotourism, is located on the green mountains of Ajloun north of Jordan, was founded in 1989 and follow The Royal Society for the conservation of the natur, an area of 13 km2, and covered with thick forests of oak trees and Butm, maple and others, characterized by the diversity of vital consists of 319 species of medicinal and aromatic plants and wild flowers, and where there are 40 species of birds, 14 species of mammals, 16 reptiles, 5 species of plants registered in the world. The Reserve has a great importance in Jordan ,it is the most reservations attractive to tourists, both internally and externally, and prov
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Shatt Al-Hilla branches from the left of Euphrates River, U/S Hindiyah Barrage, Iraq, and extends about 100 km. It branches at the end into Shatt Al-Diwaniya 112 km and Shatt Al-Daghara 64 km. The study aims to evaluate and develop (Hilla-Daghara) rivers system, which is included Shatt Al-Hilla and Shatt Al-Daghara. Fieldwork began from (26 October until December) 2020. M9, S5 devices, and the installed staff gauges were used to measure discharges and water levels, respectively. A one-dimensional model was developed for the study area by HEC-RAS, after calibration and verification by field measurements; the Manning's n of Shatt Al-Daghara is found to be 0.022. Five Scenarios were simulated to study the reach under the cu
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