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.
This Study presents and provides Variable thoughts and aspects for representing Scientific topics " Physics for instance " as Play Shows for high School Students, by Showing a suggested Method that will Contribute in illustrating the Steps of writing the educational Scientific topic, and this method will help teachers to deliver their message to the Students " receivers " easily.The researcher have used Puppets in this method as the assisting tool for teachers, to help them deliver message Clearlym easily and Joyful.The researcher in his experiment used " Archimedes Principle " as a typical example, by Converting it into a theatrical Script, with respect to the Concept of Science, and in accordance to the Scientific educational Curriculu
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Anchusa strigosa - prickly alkanet from Boraginaceae grows in roadsides, and fields of a broad range of habitats from mediterranean woodlands, to steppe vegetation, to true desert. It is commonly known as" him him" or "lisan al thawr". Anchusa can withstand hard weather conditions and hence is widely cultivated. The color of its flowers can range from pure white to deep cobalt blue. Various parts of A. strigosa are used in traditional medicine for treating several diseases or symptoms, such as abdominal pain, bronchitis, cough, and diarrhea. The goal of this study was to examine the cytotoxic effect of the crude extract of A. strigosa roots and leaves and their fractions against various tumor cell lines: adenoc
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Football is a game derived from the integration of football and tennis skills and some of the laws of volleyball and yard measurements, and since it is a newly created game must be studied and cover all aspects related to them to reach them to the highest levels. It is known that each game or sports activity should have Physical capabilities and motor skills, which is important to determine the level of technical performance where the abilities of the game contribute to mastering skills. The significance of the research in determining the standard levels of physical and motor abilities of the football players to help young professionals and the sponsors to increase the efficiency of these capabilities and thus raise the level of per
... Show MoreA simple, fast, selective of a new flow injection analysis method coupled with potentiometric detection was used to determine vitamin B1 in pharmaceutical formulations via the prepared new selective membranes. Two electrodes were constructed for the determination of vitamin B1 based on the ion-pair vitamin B1-phosphotungestic acid (B1-PTA) in a poly (vinyl chloride) supported with a plasticized di-butyl phthalate (DBPH) and di-butyl phosphate (DBP). Applications of these ion selective electrodes for the determination of vitamin B1 in the pharmaceutical preparations for batch and flow injection systems were described. The ion selective membrane exhibited a near-Nernstian slope values 56.88 and 58.53 mV / decade, with the linear dy
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The optical energy gap(Eopt) and the width of the tails of localized states in the band gap (?E) for Se:2%Sb thin films prepared by thermal co-evaporation method as a function of annealing temperature are studied in the photon energy range ( 1 to 5.4)eV.Se2%Sb film was found to be indirect transition with energy gap of (1.973,2.077, 2.096, 2.17) eV at annealing temperature (295,370,445,520)K respectively. The Eopt and ?E of Se:2%Sb films as a function of annealing temperature showed an increase in Eopt and a decrease in ?E with increasing the annealing temperature. This behavior may be related to structural defects and dangling bonds.
Background: Stroke defined by diminished cerebral blood flow, results in brain damage and neurological impairments. It often leads to considerable difficulties, such as limited mobility and compromised hand function, usually manifesting as a weakening in the ability to open and shut the hand. Objective: The study evaluates the differences between opening and closing hands when utilizing a soft robot. Methods: The study was conducted in the Mosul Specialist Rehabilitation Center which involved 68 participants, all over 20 years old, with visual impairments. The Iranian Clinical Trials Registry and Ministry of Planning approved the study, The Fugl-Meyer Assessment for Upper Extremity Action Research Arm Test, and Arm Motor Ability Test were
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The book of the summary in the control of the laws of Arabic is one of the most important books of Andalusian grammar, the resonance of which is clearly evident among the mother of the language books in the seventh century AH because of the character of the educational style easy and simplified service for anyone who wants the Nile Arabic grammar, that end through what is pursued in his book (Summary) on according to visual standards, as was Ibn Abi Al-Rabeea of first- type, and illustrated in which he addressed the analogies, and he followed the modalities expressed and its consequences relating to each attachment in which a (illness and reasoning factor) And what he said in the framework of each service for the study material in his ha
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