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 included collecting of 150 specimens of the Iraqi Bird Bulbule Pycnonotus lecuotis mesoptamiae (Pycnotidae , Passeriformes), from the 1st of November 2004 to 30th of October 2005 in the city of Baghdad and its suburbs, in concern of identifying the internal parasite of the digestive tract of these birds and studying the diseases resulted from the infection. The study showed that the bird Bulbule is Parasitized by Four types of Cestodes ,two of them are recorded in this kind of bird in Iraq for the first time ,Paradicranotinae anormalis and Haploparaxis sp. , and the other two are Raillietina tetragona and Allohymenolepsis sp. ,and by two types of Pin Worm(Trematode) that are identified for the first time in the Bird Bulb
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Perceived Trust of Stakeholders: Predicting the Use of COBIT 2019 to Reduce Information Asymmetry
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Due to economic reasons or need for environmental conservatism or also preserve the natural resources; there has been an increasing shift towards the use of reclaimed asphalt pavement (RAP) materials in the pavement construction industry. Therefore, use the Reclaimed Asphalt Pavement (RAP) has been enormously increased in pavement construction and has been become common practice in many countries. Nevertheless, this is a relatively new concept in Iraq, and has to be remarked that is not used RAP in the production of HMA and this valuable material is mostly degraded. For this purpose, the reclaimed materials were collected from deteriorated pavement segments. The components of asphalt mixtures consist of: two asphalt penetration grades (40-5
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The atmospheric air cold plasma has been used to manufacture gold nanomaterials for treating parasitic leishmaniasis. This study experimentally assessed the treatment of Leishmania parasites (L. donovani and L. tropica) by gold nanoparticles. Specifically, atmospheric pressure nonthermal plasma was generated using different diameters (1.0, 2.8, 3.8 and 4.3 mm) of high voltage electrode. Aqueous gold tetrachloride salts (HAuCl4·4H2O) were used as precursor to produce gold nanoparticles. UV-vis spectroscopy and x-ray diffraction were conducted for characterization of the nanoparticles. The optimum condition (a diameter of 1 mm) was chosen to prepare gold nanoparticles, where the grain size was found to be 17 nm. Accordingly, the nanoparticle
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Intended for getting good estimates with more accurate results, we must choose the appropriate method of estimation. Most of the equations in classical methods are linear equations and finding analytical solutions to such equations is very difficult. Some estimators are inefficient because of problems in solving these equations. In this paper, we will estimate the survival function of censored data by using one of the most important artificial intelligence algorithms that is called the genetic algorithm to get optimal estimates for parameters Weibull distribution with two parameters. This leads to optimal estimates of the survival function. The genetic algorithm is employed in the method of moment, the least squares method and the weighted
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A theoretical calculations of the rate constant of electron transfer (ET) in a dye – semiconductor system with variety solvent are applied on system contains safranineT dye with TiO2 in many solvents like water, 1-propanol, Formamide, Acetonitrile and Ethanol.
A matlap program has been written to evaluate many parameters such that, the solvent reorganization energy, effective free energy, activation free energy, coupling matrix element and the rate constant of electron transfer.
The results of the rate constant of electron transfer calculated theoretically are in a good agreement with experimental and theoretical value
... Show MoreSarcophaga africa Fall. considered to be medical and veterinary importance, therefore, its third larval instar was described by digital camera under compound and dissecting microscope. This description includes spines type, shaped and cephalopharyngeal skeleton. Furthermore the anterior and posterior spiracles were also studied.
The aim of this research is to determine the concentrations of uranium in human blood in some regions of Baghdad governorate and to determine the level of contamination with uranium for these regions during the (2003) war. The results obtained have shown that the maximum uranium concentration in blood samples was found (0.256 ppm) in AL-Zaifranea region and AL-Sader city,while the minimum in AL-Shab region (0.052 ppm) ,the minimum of uranium concentration in the blood samples was found to be (0.008 ppm) (male,39 years old) lived in AL-Shab region, while the maximum of uranium concentration in the blood samples was found to be (0.44 ppm) (female, 55 years old ) lived in AL-Sader city.
Nicotiana tobaccum L (Solanacea) extracts are used as a mollusciede to the snail Bulinus truncatus the intermediate host of urinary Schistosomiasis. LC50 of the extracts to the snail with 24 hour was 3.27 ml/l? 48 hour was 3.33 ml/l? 72 hour was 2.67 ml/l and 96 hour was 2.28ml/l. This study showed the ability to use the leaf extracts in the control of this type of snail.