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.
Abstract: This research was performed to study the effect of some amino acids and vitamins on the growth of bacteria Staphylococcus aureas and its sensitivity against UV light. The results showed low inhibition in bacterial growth because amino acids repairs the damges caused by UV light. Besides the effect of two groups of antibiotics (β-lactame and tetracycline) on the growth of S. aureus and the possible interference of amino acids and vitamins in the activity of the antibiotics against this bacteria in the presence of UV light were studied. The result show increase in the sensitivity towards these antibiotics and provided protection against the antibiotics.
We have presented the distribution of the exponentiated expanded power function (EEPF) with four parameters, where this distribution was created by the exponentiated expanded method created by the scientist Gupta to expand the exponential distribution by adding a new shape parameter to the cumulative function of the distribution, resulting in a new distribution, and this method is characterized by obtaining a distribution that belongs for the exponential family. We also obtained a function of survival rate and failure rate for this distribution, where some mathematical properties were derived, then we used the method of maximum likelihood (ML) and method least squares developed (LSD) to estimate the parameters an
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Autorías: Wafaa Sabah Mohammed Al-Khafaji, Fatimah Hameed Kzar Al-Masoodi, Suadad Ibrahim Suhail Al-Kinani. Localización: Revista iberoamericana de psicología del ejercicio y el deporte. Nº. 3, 2023. Artículo de Revista en Dialnet.
This study is concerned with shedding light on the grammatical method of Ibn Hisham Al-Ansari (761 AH), in his explanation of Bant Souad’s poem by the poet Kaab bin Zuhair, and I included a brief description of Ibn Hisham’s life with a number of explanations of this poem, then clarified the most important features of this method The grammar represented by his reliance on hearing and presenting it to analogy with mention of types of analogy, as well as his attribution of opinions to their owners with weighting, selection and balancing, and his attention to reasoning and a number of grammatical ailments, and his approach is also distinguished by following the method of fractal.
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Abstract
Personality is one of the most important elements that should be developed in university student. Thus, we have to develop the positive traits and neutralize the negative traits of students as well as we have to pay attention to the level of student achievement at the same time, the researcher designed a scale to measure the traits of study sample. The research come out with a number of recommendations and proposals, the most important of which Enhancing the positive characteristics of university students in order to reach them to the level of mature personality with mental health. Enhancing the positive role of the high level of achievement by motivating the stude
... Show MoreGod Almighty singled out Arab nation to carry divine messages، and make them the land of Iraq to store the soil prophets and apostles and grandchildren of Al al-Bayt، peace be upon them as they were and are still a beacon for people، Shrines and monuments and flags، frequented by science students from various walks of life، were are shrines representing the name of Iraq by the private and the nation of Islam in general، sung by the preacher and artist and writer
The book "News of Time in the History of Bani Abbas" for Khazraji of important historical books, because of the news of the sons of Abbas, which is part of the book (Alosdp Almstok in the history of Islam, the layers of kings, ranked on the years starting from the emergence of Islam
Les sociétés d’assurances sont considérées parmi les importantes entreprises financières non bancaires.
Pour que ces sociétés assurent sa continuité d’existence, il faut qu’elles veillent au rendement financier qui représente ses différentes actions durant une période déterminée, en effectuant une évaluation permanente en utilisant de différentes méthodes parmi lesquelles l’analyse financière avec ses aspects divers.
L’objectif de cette étude est d’évaluer le rendement financier des sociétés d’assurances et où projette l’étude sur la société Algérienne d’assurance durant la période 07- 09.