The present work presents design and implementation of an automated two-axis solar tracking system using local materials with minimum cost, light weight and reliable structure. The tracking system consists of two parts, mechanical units (fixed and moving parts) and control units (four LDR sensors and Arduino UNO microcontroller to control two DC servomotors). The tracking system was fitted and assembled together with a parabolic trough solar concentrator (PTSC) system to move it according to information come from the sensors so as to keep the PTSC always perpendicular to sun rays. The experimental tests have been done on the PTSC system to investigate its thermal performance in two cases, with tracking system (case 1) and without tracking system (case 2). The experimental results showed that the average solar radiation falling on the PTSC prototype in the two cases during the same time was 854 and 701 watt/m2, respectively, which means an increase in the solar radiation about 21.8 % when using tracking system. It was found that the average useful heat gain output of solar collector was equal to (376.2, 252.6 watt) for the two cases, respectively, so there was an increase of about 48.9 % when using the tracking system. Also, the average thermal efficiency of the PTSC was found to be (20.7, 26.5 %) for the two cases, respectively, which means an increase in the average efficiency by 28% with use of tracking system compared to the fixed case.
The experiment was carried out in the spring season of 2017 in the open fields of the College of Agricultural Engineering Sciences/University of Baghdad/Al-Jadriya camps in order to improve the growth and yield of potato plants resulting from the cultivation of true potato seeds of the hybrid BSS-295 by spraying with two organic nutrients. The experiment included two factors: First one was spraying with Megafol nutrient at concentrations 0, 1, 2 and 4 ml l-1 and the second was spraying with Algazone nutrient at concentrations 0, 1.5 and 3 ml l-1, the experiment was applied according to the complete randomized block design with three replicatio
New schiff bases series (VIII) a-e and 1,3-thiazolidin-4-one derivatives (IX) a-e containing the 1,2,4-triazole and 1,3,4-thiazazole rings were synthesized and screening their biological activities. These compounds were identified via Fourier transform infrared (FT-IR) spectra, some via Proton nuclear magnetic resonance (1H-NMR) and mass spectra. The biological results indicated that all of these compounds did not reveal antibacterial effectiveness against (Escherichia coli and Klebsiella species) (G-). Some of these compounds showed moderate antibacterial activity against (Staphylococcus aureus, and Staphylococcus epidermidis) (G+), and all compounds exhibited moderate activity against Candida albicans.
This research aims to Presented model can be applicable – in the frame of current accounting implementations - to measure environmental effects and disclosure then in the financial statements of economic entities after determined the environmental performance scopes of environmental activities that is works by this entities , because of importance of accounting information which presentation by accounting systems which's effectiveness tool on hand of decision maker about site plans and goals and drawing policies aims protection environment sustainable the represented of naturalism wealth elements . The researcher could be able to application his suggested model which's proof the ability to environmental accounting measurement and discl
... Show MoreIn current study a computation fluid dynamic (CFD) technique was used to investigate the effect of groynes shape and spacing on the scour pattern and the maximum scour depth in open channel flow. CFD model have been validated throughout comparing the numerical results with three previous experimental studies for a single groyne located in open channel with three different shapes (L, quadrant, and parabola shapes). The comparison revealed very good agreement between numerical results of the maximum scour depth with the results of all experimental models. Moreover, investigations of the effect of multi-groynes (three groynes and four groynes) arranged in parallel with constant spacing and also with variable spacing have been done, the
... Show MoreLeishmania parasites reproduce wherever there are cells of the mononuclear phagocyte system, almost in macrophages. These are most copious in the liver and spleen;therefore, infection leads to an expansion of both of them. This study determined the burden of visceral leishmaniasis (VL) infection on liver and spleen. A total of 20 mice were infected peritoneally with 2x107promastigotes of Leishmania donovani / ml and other 12 mice left without infection as a healthy control. The weight of whole body, liver and spleen were measured and the histological development using hematoxylin and eosin stains were determined after 15, 30, 45-and 60-days post infection. The results represent that the mean weights of liver and spleen were increased in inf
... Show MoreThe influence of sintering and annealing temperatures on the structural, surface morphology, and optical properties of Ag2Cu2O4 thin films which deposited on glass substrates by pulsed laser deposition method have been studied. Ag2Cu2O4 powders have polycrystalline structure, and the Ag2Cu2O4 phase was appear as low intensity peak at 35.57o which correspond the reflection from (110) plane. Scan electron microscopy images of Ag2Cu2O4 powder has been showed agglomerate of oxide particles with platelets shape. The structure of thin films has been improved with annealing temperature. Atomic Force micrographs of Ag2Cu2O4 films showed uniform, homogenous films and the shape of grains was almost spherical and larger grain size of 97.85 nm has o
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