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Design and Implementation of an Automatic Control for Two Axis Tracking System for Applications of Concentrated Solar Thermal Power
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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.

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
Work pressure of the administrative and academic members of Biskra University, its sources and its relation to some personal and functional variables
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  The study aimed to highlight the reality of the functional pressures with its dimensions (role ambiguity, role conflict, role burden, glass ceiling, and discrimination in composition). The researchers also relied on the questionnaire as a essential tool for data collection. The field study was conducted at the University of Mohammed Khiedr - Biskra -, the study was conducted on the basis of the total survey, which included all the workers of the 6 faculties of Biskra University (523 female employees).

     After the analyzing of the data using the version 21 of the statistical program Spss, The study reached a number of results, the most of them is the low level of the functiona

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Effect of physical form and washing of treated and untreated rice straw with sodium hydroxide upon chemical composition and in vitro digestibility
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Hydroxide upon the chemical composition and dry matter(DM) and organic matter(OM) digestibility . Rice straw was treated with 4% sodium hydroxide using 30% of DM basis moisture, and incubated at 40 ºC for 40 days., DM digestibility (DMD) was significantly affected (P<0.01) by the treatment , where DMD increased The objective of this experiment was to study the effect of physical form (long ,chopped and ground ) and washing rice straw treated with sodium from 42.32 to 45.41% , OM digestibility (OMD) and total digestible nutrient (TDN) increased(P<0.05) from 47.38 and 49.33 to 49.67 and 52.83% ,respectively. While hemicellulose content increased (P<0.05 ) from 261.71 to 268.17 gm/kg DM ,and metabolizable energy (ME) from 7.11 to 7.48 MJ/

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Publication Date
Wed Sep 15 2021
Journal Name
Geomechanics And Geoengineering
Effect of Deep Remediation and Improvement on Bearing Capacity and Settlement of Piled Raft Foundation Subjected to Static and Cyclic Vertical Loading
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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Kinetics of the Saponification of Mixed Fats Consisting of Olein and Stearin
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This research presents the kinetics of the saponification reaction using mixed fats of olein and stearin [in the ratio (3:1)] with NaOH solution. In this reaction, excess solution of NaOH was used to ensure the reaction being irreversible. Three parameters were varied to show their effects on the reaction rate .They are: percentage excess of NaOH solution (10 % - 100 %) , temperature (100-150)oC , and stirring speed (400-1100) rpm. It was noticed that increasing the percentage excess of NaOH solution enhances the rate of reaction while increasing temperature decreases the reaction rate since it is exothermic reaction.    Increasing stirring speed also improves the reaction rate because it is mass transfer controlled .Calcu

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Publication Date
Wed May 17 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Modeling of the Effect of MgO and ZrO2 on Sintering of Alumina
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  This research  studyies the effect of MgO and ZrO2 as additives in sintering Al2O3 . The experimental results are modeled using ( L2 _ regression) technique , sintered density and grain size rate measurments were  accounted by utilizing experimental results of undoped , MgO doped and ZrO2  doped alumina impregrated with spherical large pores in final stage of sintering . The effect of each additive is inhibitian of the grain growth and increasing the densification rate which enhances the kinietics of densification and the removal of large and small pores.

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Publication Date
Wed Jun 28 2023
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
PREPARATION OF A COMBINATION OF NANO- MEDICINAL PLANTS AS ANTIOXIDANTS AND MICROORGANISMS: PREPARATION OF A COMBINATION OF NANO- MEDICINAL PLANTS AS ANTIOXIDANTS AND MICROORGANISMS
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ABSTRACT

            The controversy is currently revolving around industrial additives, including antioxidants, their negative effects on consumer health and the emergence of various and various diseases, which led scientists and researchers to intensify most studies on natural antioxidants and their synthesis from medicinal plants mentioned in ancient medicine and in divine books as potential antioxidants of increasing importance. Therefore, this study was designed to synthesize silver nitrate particles from plant leaf extracts (Figs, Olives, and Moringa) and study their effect on bacterial inhibition of each of the undesirable Coliform bacteria (E-Coli,

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Publication Date
Wed Jan 15 2025
Journal Name
Modern Sport
Comparison of the speed of hospitalization according to the training load of some physiological and biochemical variables of badminton players and runner800 m youth
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It is necessary to use the means of recovery and other means that help to get rid of the effects of fatigue, as the game of badminton and the effectiveness of running 800 meters fall within the mixed system with the superiority of the anaerobic system by more than the air system, so requires the development of energy systems In proportion to the time of the match for badminton players and their travels and high performance and ability to tolerate the high level of lactic acid in the muscles and blood and increase the pain associated with the fatigue that occurs during the performance. In light of the physical and physiological processes of these actions N it should seek through training programs to develop your endurance and wind energy sys

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Publication Date
Wed Jun 30 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
IRAQI CONSUMER OPINION OF THE QUALITY AND SAFETY OF LOCAL FOOD PRODUCTS: IRAQI CONSUMER OPINION OF THE QUALITY AND SAFETY OF LOCAL FOOD PRODUCTS
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The aim of this research was to indicate the opinion of the Iraqi consumer about the quality and safety of local food products, the questionnaire was included 19 questions for product quality, price, distribution and promotion as a tool to survey the opinions of 128 consumers in Baghdad, the data was analyzed by using percentage, weighted mean, and weight percent, the results obtained showed that the Iraqi consumer prefer local food products for their high quality and appropriate price, however they need attention to packaging, promotion and distribution.

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Publication Date
Wed Jan 15 2025
Journal Name
Al-rafidain University College For Sciences
Uncertainty types and theories of treatment
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In this research the researcher had the concept of uncertainty in terms of types and theories of treatment and measurement as it was taken up are three types of indeterminacy and volatility and inconsistency

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Publication Date
Sun Jun 03 2018
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Formulation and Evaluation of Acyclovir Microspheres
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The present study is to formulate and evaluate Acyclovir (ACV) microspheres using natural polymers like chitosan and sodium alginate. ACV is a DNA polymerase inhibitor used in treating herpes simplex virus infection and zoster varicella infections. Acyclovir is a suitable candidate for sustained-release (SR) administration as a result of its dosage regimen twice or thrice a day and relatively short plasma half-life (approximately 2 to 4 hours). Microspheres of ACV were prepared by an ionic dilution method using chitosan and sodium alginate as polymers. The prepared ACV microspheres were then subjected to FTIR, SEM, particle size, % yield, entrapment efficiency, in vitro dissolution studies and release kinetics mechanism. The FTI

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