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.
There are no words in the universe that are collected, communicated, raised, and greater than the words of God, Lord of the worlds, and there is no guidance except with Him, nor guidance except with His guidance, and no knowledge except with Him, and how is he guided by the lost without guidance from God Almighty !?
In this research, I tried to address what collects hearts, composes souls, and spreads love among members of society as part of the social twinning and good coexistence between people. Harmony, love, and the roots of fragmentation, fighting and feuding.
This verse is blessed and I chose {Taking the Charter of the of Israel do
... Show MoreThe aims of this study the infection with parasites Entamoeba histolytica and Giardia lamblia and prevalence rates and their relationship with gende , age group , the number of family members and source of drinking water among the patients at attending the Bint Al Huda and Al- Hussin Teaching hospital in Nassriyia city in Thi- Qar province , it was noticed that the percentage of parasitic infection at females was 38.55% and at males was 61.45% and the percentage of parasitic infection with Entamoeba histolytica 97% was higher than the percentage of parasitic infection with Giardia lamblia 3%,and the reduction of percentage of infection is associated with increasing of the number of family member ,the percentage of infection was 49% at the
... Show More
(1)
(1)
(1)
Recently on the dermatological fields, the serum levels and the roles of Zn, Cu and Mg have been studied especially in acne vulgaris, but the results were controversial. The aim of the present study is to investigate a relationship between the severity of acne and the serum levels of zinc (Zn), copper (Cu) and magnesium (Mg) and to demonstrate the status of serum levels of zinc, copper, and magnesium in Iraqi male patients with acne vulgaris and to compare it with those of healthy controls.This case controlled study was conducted in the Department of Dermatology and Venerology and in the Poisoning Consultation Center of Baghdad Teaching Hospital between May 2009 to January 2010. Forty- five male patients with acne vulgaris, their a
... Show More
the traumatic memory of their ancestors. The novel navigates sites of trauma, memory, and blues music while resisting the bourgeoisie-capitalist relationships that permeated not only white society but also African American communities. Jones’s novel presents the plight of an African American woman, Ursa, caught between the memory of her enslaved foremothers and her life in an emancipated world. The physical and spiritual exploitation of African American women who bear witness to the history of slavery in Corregidora materializes black women’s individuality. This article is framed by trauma studies as well as the Marxists’ concepts of commodification, accumulation, and production. Ursa, one of the Corregidora women, represents
... Show More
Diabetes mellitus type II is a disorder of metabolism and complex diseases affected by genetic environmental factors and associated with inflammation. The symptoms of type II diabetes develop gradually, which are associated with increased blood concentration of marker of the endothelial inflammatory factors. The expression of adhesion molecules, including E-selectin, intracellular adhesion molecule-1(ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on the surface of vascular endothelial cells to help leukocyte stick to other surrounding tissues. Many researchers have made attempts to determine the significance of particular ABO phenotype for the susceptibility to diseases. Many reports show a strong association with the ABO blood grou
... Show More
Evaluating treatment effect on interferon-alpha in female patients with systemic lupus erythematosus: a case-control study
The research endeavors to harness the benefits stemming from the integration of constraint theory into construction project management, with the primary goal of mitigating project completion delays. Additionally, it employs fuzzy analysis to determine the relative significance of fundamental constraints within projects by assigning them appropriate weights. The research problem primarily revolves around two key issues. Firstly, the persistent utilization of outdated methodologies and a heavy reliance on workforce experience without embracing modern computerized technologies. Secondly, the recurring problem of project delivery delays. Construction projects typically encompass five fundamental constraint types: cost restrictions, tim
... Show More