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:
The current research is aimed at analyzing the impact of the dimensions of Job involvement of all of (the enthusiasm, the Devotion, Assimilation ) in the Crystallize organizational Identification across the dimensions of (organizational loyalty, membership, similarities) and was named the Middle East, the Iraqi Investment Bank room to look as the research community of staff adopted in the bank, to be applied to a Random sample of (100) employees working in the said bank, and developed for the purposes of data collection, a questionnaire form included three axes covered (32) paragraph of the measure, which is included adopted Liekrt Quintet for the
... Show MoreSummary of the discussion of the jurisprudential aspects of Imam Abu Al-Fayyad Al-Basri, and their impact on the Shafi’i school, on the provisions of transactions, personal status, janaabah, limits, and others
Praise be to God, Lord of the Worlds, and prayers and peace be upon the Master of the Messengers, our master Muhammad, and upon his pure family, and his ignorant and ignorant companions, and those who followed them in goodness until the Day of Judgment.
Then:
The many jurisprudential aspects that the Shafi’i imams said are of great importance, because these aspects are nothing but the opinions of venerable jurists who have reached a high degree of knowledge unti
... Show MoreThe objective of this study is to highlight the skills of office managers and it's impact on the effectiveness of time management in the institutes and faculties of middle technical university and a group of cognitive and practical aims. The managers skills forms mthe modern trend and the main source to provide organizations with highly skilled managers with distinctive performance and because of the sharp changes in the environment which today's organizations works in it , business organizations generally and managers especially realise the importance of time management and it's role in achieving competitive advantage . The problem of this study raised from this point which reflect the extent of departments managers realisation
... Show MoreThis research aims to find out the phonemic, dialect and semantic ailments that were interrogated by the book of the parsing of thirty surahs of the Noble Qur’an by Ibn Khalawiyeh, by examining some phonemic phenomena of Qur’anic expressions and their explanatory relationships that resulted in their occurrence, such as substitution and compression, as the sounds in a word are affected by one another, especially during performance and composition. This influence and influence is the tendency of the human being to the law of ease, facilitation, and the reduction of muscular effort in speech often, all for the purpose of obtaining phonemic harmony for the compound letters; To facilitate pronunciation; And get rid of the muscular effort
... Show MoreThe increase in obesity and the many accompanying diseases is attributed to the increased production and consumption of foods made of non-nutritive sweeteners without regard to the risks of consuming additional calories, and this in turn leads to hormonal imbalance and metabolic disorders and the resulting imbalance and ill health that have spread to all segments of society. During the research, 0.01, 0.02, 0.03, 0.04 and 0.05 % of stevia sweetener was added to the cream instead of the sugar used. Physical and chemical tests were performed for the stevia extract and the microbial content in the cream, as well as the sensory evaluation. It was noted that fortifying the cream with calorie-free stevia sugar led to the production of
... Show MoreIn this study, some physical and mechanical properties of soil samples collected from the campus site of College of Science, University of Diyalahave been evaluated. All laboratory tests were performed according to the standards of American Society for Testing and Materials (ASTM). The test results showed that the range of soil water content wwas (13.89%-16.34%) with an average of 15.44%. The specific gravity range was (2.58-2.77) with an average of 2.66. The range of Liquid Limit LL was (26.20-35.20%) with an average of 32.22%.The range of Plastic Limit PL was (18.63-23.24%) with average of 21.06%. The range of Plasticity Index was (7.57-12.42) with an average of 11.61. Based on USCS classifications, the soil can be considered
... Show MoreActive compounds were extracted from Anethum gravoelens to produce safety vegetable treat for diabetic, the results showed that alcoholic extract of Anethum gravoelens contain Alkaloid, glycosides, phenols, resins, saponins, coumarins, flavonoide, terpenes, steroids and volatile oils. after that it was studied the effect of alcoholic extract at dose 50, 100 mg/kg of body weight in reduced glucose level in serum of diabetic rats induced by alloxan, after the end of experiment for period 30 days the rats fasting 12 hours to measure the level of glucose in serum, the result showed asignificant decrease in serum glucose level of rats treated with extract in comparison with positive group (alloxan), So biochemical tests showed significant dec
... Show MoreChallenges facing the transition of traditional cities to smart: Studying the challenges faced by the transition of a traditional area such as Al-Kadhimiya city center to the smart style