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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
Wed Dec 25 2024
Journal Name
Journal Of Baghdad College Of Dentistry
An Assessment of Alpha-Amylase as Salivary Psychological Stress Marker in Relation to Temporomandibular Disorders among a Sample of Dental Students
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Background: University dental students perceived a higher level of stress prior to the final exam associated with raised salivary alpha-amylase levels which could be considered as a useful noninvasive biomarker for measuring acute stress. Using a Helkimo anamnestic and clinical dysfunction scoring for temporomandibular disorders can give a better insight about the association of this marker and temporomandibular disorders. The aim of this study was to evaluation level of salivary alpha-amylase in stressor students with temporomandibular disorders and the relation between the marker in relation to temporomandibular disorders severity. This might give a better understanding to the role of psychological stress as an etiological factor for deve

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Publication Date
Wed Dec 25 2024
Journal Name
Al–bahith Al–a'alami
International Public Relations (An Analytical Study of the Speeches of US President Barack Obama Addressed to the Arab Countries in Crisis)
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In the midst of political, cultural and economic fast developments accelerated, the world witnessed, with the accompanied big communication revolutions, many shapes of powers. Those developments were followed by changes in relations of international level.

The most prominent among those developments was the international public relations which became equal to official international relations. Moreover, the international public relations became a complementary element dur to the growth of public opinion and its affection on political regime. Such growth of public opinion pushed the politicians to address it; and try to gain its support.

The US was the first realized the importance of international public relations. Th

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Publication Date
Mon Sep 30 2024
Journal Name
South Eastern European Journal Of Public Health
Antimicrobial Efficacy of a Novel Herbal Endodontic Irrigant Against Enterococcus Faecalis in Root Canals of Permanent Teeth: An in Vitro Study
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Background: A successful endodontic treatment is aimed at the sterilization of the entire pulp space. The use of extracts from Rhamnus prinoides as a novel irrigating material for root canal has not been studied . Hence, the antimicrobial efficacy of the alcoholic extract of Rhamnus prinoides as an irrigation material against E. faecalis was evaluated in comparison with the 2.5% sodium hypochlorite (NaOCL) solution used for root canals of permanent teeth. Methods: A total of 30 single-rooted human permanent teeth were thoroughly cleaned, shaped, and disinfected. Then, each tooth was subjected to a two-week infection with Enterococcus faecalis at 37 °C . Afterward, the samples were divided into three groups (10 teeth per group): 0.9

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Publication Date
Thu Nov 30 2023
Journal Name
Iraqi Journal Of Science
Novel Nano Zn+2-Compound from LA Ligand as an Acid-Base Indicator: Synthesis, Characterization, pH Sensor, and Fluorescent Study
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The main goal of our research is to synthesize novel nano Zn2+ complex with the 8-(2-(dansyl chloride)azo) adenine (LA) ligand as a pH sensor because of its advantageous properties, obtained from a single molecule. The Zn2⁺- LA complex was based on the production of an intensely dark purple-colored substance with λmax at 552 nm. Molar ratio of Zn2⁺- LA complex is a 1:2 in aqueous buffer. The optimum concentration (0.3) mM, pH (2-5.5), and time (0-3) hr at pH=5.5, that in the studies followed Lambert-law Beer'

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Publication Date
Tue Sep 27 2022
Journal Name
Al–bahith Al–a'alami
POLITICAL DEBATES AND THEIR ARTISTIC CONSTRUCTION IN IRAQI SATELLITE CHANNELS ( AN ANALYTICAL STUDY ) : (A research drawn from a Master Thesis)
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The problem of research on the study of political debate programs in the Iraqi satellite channels, in the "People decide" program by Afaq channel and " electoral competition " by Fallujah channel), and its importance for the community and researchers in the scientific field, as new programs to enter the Iraqi media after we have been the world media a lot in this area at the academic and practical levels (The field), and seeks to find out what the technical construction of the programs of political debates in Iraqi satellite channels and methods of construction and methods of employment used by the technical elements in the presentation of the programs and The study adopted the surve

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Publication Date
Mon Feb 18 2019
Journal Name
British Journal Of Neurosurgery
An enemy hides in the ceiling; pediatric traumatic brain injury caused by metallic ceiling fan: Case series and literature review
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Purpose: We report a series of 29 pediatric patients who sustained head injuries due to metallic ceiling fans. They all were admitted to the Emergency Department of Neurosurgery Teaching Hospital in Baghdad, Iraq, during January 2015 to January 2017. Results: Pediatric ceiling fan head injuries are characterized by four traits which distinguish them from other types of head injuries; 1- Most of them were because of climbing on or jumping from furniture between the ages of two and five. 2- Most of them sustained compound depressed skull fracture which associated with intracranial lesions and pneumocephalus. 3- The most common indication for surgical intervention was because of dirty wound which mixed with hairs. 4- These variables were stati

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Publication Date
Thu Nov 04 2021
Journal Name
Optik - International Journal For Light And Electron Optics
Plasma parameters of Au nano-particles ablated on porous silicon produced via Nd-YAG laser at 355 nm for sensing NH3 gas
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The current study aimed the syntheses and characterizations of Gold nanoparticles (Au NPs) using a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the

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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of Sport Sciences
The effect of using the McCarthy model according to cognitive style (rigid- flexibility) in learning some skills in artistic gymnastics for women
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The aim of the research is to identify the cognitive method (rigidity flexibility) of third-stage students in the collage of Physical Education and Sports Sciences at The University of Baghdad, as well as to recognize the impact of using the McCarthy model in learning some of skills in gymnastics, as well as to identify the best groups in learning skills, the experimental curriculum was used to design equal groups with pre test and post test and the research community was identified by third-stage students in academic year (2020-2021), the subject was randomly selected two divisions after which the measure of cognitive method was distributed to the sample, so the subject (32) students were distributed in four groups, and which the pre te

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Publication Date
Tue Jun 08 2021
Journal Name
مجلة العلوم و التكنولوجية للنشاطات البدنية و الرياضية
The effectiveness of using (7E’s) learning cycle in learning a movement chain on the uneven bars in the artistic gymnastics for women
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Abstract The Object of the study aims to identify the effectiveness of using the 7E’s learning cycle to learn movement chains on uneven bars, for this purpose, we used the method SPSS. On a sample composed (20) students on collage of physical education at the university of Baghdad Chosen as two groups experimental and control group (10) student for each group, and for data collection, we used SPSS After collecting the results and having treated them statistically, we conclude the use 7E’s learning cycle has achieved remarkable positive progress, but it has diverged between to methods, On this basis, the study recommended the necessity of applying 7E’s learning cycle strategy in learning the movement chain on uneven bar

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Publication Date
Mon Jan 30 2023
Journal Name
Iraqi Journal Of Science
Potential of Using Limestone Rocks Accumulated in Al-Samawa Stone Quarry, South Iraq, for The Stationary Phase in A Column Chromatography Separation
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     This investigation aims to determine whether it is feasible to use the limestone rocks found in the Al-Samawa stone quarry in southern Iraq as the stationary phase in column chromatography separation. Together with the chromatographic application, the physical and chemical characteristics of the rocks are examined. SiO2, SO4, PO4, NO3, and Cl are the negative ions, while Ca, Mg, Na, K, and Li are the positive ions. The limestone samples are characterized via chromatographic analysis. The results suggest that limestone samples could be used as an adsorbent material for chromatographic separation techniques. Additionally, samples from the Nasiriyah refinery's crude oil can be used to sep

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