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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 Sep 30 2022
Journal Name
Iraqi Journal Of Science
Assessment of Heavy Metals Concentration in Water and Fish of Dalmaj Marsh, Iraq
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    Most marshes in Iraq face several challenges as aquatic environments, including pollution by various chemical agents and heavy metals. The current study deal with an analysis of the water quality of Dalmaj marsh as one of the closed aquatic environments in the middle parts of Iraq located between latitudes 32ᵒ 05′ to 32ᵒ 23′N and longitudes 45ᵒ 10′ to 45ᵒ 38′ E. The marsh is suffering from a shortage in water supply, especially during the summer. It will lead to a concentration of heavy metals that are washed and transported to the marsh from the surrounding watersheds through surface runoff. This work aims to analyze water and fish samples to assess heavy metals and their accumulated risk in fish tissues based on

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Publication Date
Sun Jan 03 2016
Journal Name
Journal Of Educational And Psychological Researches
Professional competencies and teaching university professor from the point of view of students
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Targeted Search:

-scale preparation of teaching and professional competencies required for university professor from the perspective of students from different disciplines.

-scale application prepared by the researcher for the students to see how their preference for these competencies to their professors.

-limited Search: Find determined to present the following

-students of both sexes in the University of Baghdad.

2013 -      2012

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Publication Date
Mon Aug 31 2015
Journal Name
Ibn Al-haitham Jour.for Pure & Appl.sci.
Isolation and Partial Purifiction of Arginase from Sera of Women with Uterine Fibroids
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The first aim of the present study was performed to assay the activity of arginase in sera of women with uterine fibroid.. This study consisted of(50) women with uterine fibroid as patient's group and (30) healthy women as control group. The age ranged between (30-55) years for the two groups. The results showed that highly significant increase (P< 0.0001) in the arginase activity in sera of women with uterine fibroid (7.99± 0.23) I.U/L is found when compared with healthy group (0.52±0.02) I.U/L. The second aim was performed to isolate arginase from sera of women with uterine fibroids. The purification is done by addition of ammonium sulfate, dialysis, gel filtration chromatography by using sephadex G-50 and ion exchange chromatography

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Publication Date
Wed Jul 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Simulation and Evaluation of a Variable Effective Focal Length of Refractive Binocular Telescope
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The telescope works to magnify images of distant objects in general, but it needs special optical elements to complete the task to the fullest. The telescope needs optimal balance values of the optical parameters used to produce the best image, such as the effective focal length and the diameter of the pupil aperture, which are combined in a single concept called the focal number. The ground-based binary telescope relies on special lenses and an exceptional prism to achieve a hybrid design that produces clear images of relatively distant terrestrial objects. The pupil diameter of the telescope is relatively large to ensure that the largest possible amount of light is received, and as a result, a good image is obtained.

In this wo

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Publication Date
Sat Jan 01 2022
Journal Name
المجلة العراقية لعلوم التربة
EFFECT OF UREA AND NPK FERTILIZER ON SOME PHYSIOLOGICAL CHARACTERISTICS OF WATERCRESS PLANT
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The experiment was conducted in the botanical garden of the Department of Life Sciences/ College of Education for Pure Sciences Ibn Al-Haitham for the growing season 2021- 2020 in order to study the effect of urea and NPK fertilizer on some physiological characteristics of watercress plants. The seeds were sown on 10/15/2020 in plastic bags weighing 10 kg of soil. The shoots were sprayed with urea at three concentrations (0, 50, 100) mg L-1 in two sprays, and NPK fertilizer was added as a ground addition at three levels (0, 100, 200) kg H-1 in two sprays in conjunction with urea spraying. The results of the study showed a significant effect for the single treatments. The treatment of spraying with urea at a concentration of 50 mg l-1 . was

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of The College Of Basic Education
Some Thermodynmic Properties of binary Mixtures of Alcohol isomers and Sulfolane at 298.15K
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The refractive indices, nD densities 𝜌, and viscosities  of binary mixtures of sulfolane + n -butanol + sec- butanol + iso- butanol + tert – butanol + n-propanol and iso- propanol were measured at 298.15K. Form experimental data, excess molar volum VE , excess molar refractivity ∆nD, excess molar viscosity  E and excess molar Gibbs free energy of activation of viscous flow G *E were calculated. From n-propanol – sulfolane and iso- propanol sulfolane mixtures showed negative ∆nD, n-butanol – sulfolane, sec-butanal – sulfolane, iso-butanol – sulfolane and tert- butanol sulfolane , nD was positive over the whole mole fraction rang , while VE ,  E and G *E show a negative deviation. The

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Publication Date
Mon Sep 25 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Preparation and Characterization of A New Nano-scaled Material Composed of Bentonite-Polyethylenglycophthalate
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   In this study a new composite material have been prepared and characterized through polymerization of ethylene glycol located between the Bentonite layers with phthalic anhydride. The results showed that the polymer binds with the structure of clay through hydrogen bonding also the polymerization process led to shatter of the three-dimension crystal structure of the clay and isolating layers in the form of nano-scale two-dimensional sheets, the polymer growth around the clay isolated layers work to increase the size particles at microscopic scale.                              &

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Publication Date
Thu Jan 30 2020
Journal Name
Journal Of Engineering
Influence of Additives on Permanent Deformation and Resilient Modulus of Recycled Asphalt Concrete
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Tests were performed on asphalt concrete specimens with (101.6 mm in diameter and 101.6 mm in height), and the results were implemented for calculating permanent deformation and resilient modulus under repeated compressive stress with different levels of stresses (0.068, 0.138 and 0.206) MPa at 40 ºC. Two types of additives namely (carbon black-asphalt) and (SBR-asphalt) were tried as rejuvenators with three percentages of (0.5, 1 and 1.5) % by weight of asphalt cement along with two ratios of AC (1 and 2) % have been implemented as rejuvenator and blended with the reclaimed asphalt concrete. Aged materials were obtained from the site. 100% Reclaimed Asphalt Pavement material from the reclaimed mixture is implemented. A

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Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Antiplatelts Activity of Vitamin E in Relation to Dose and Duration of Therapy
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           Vitamin E, having the well known antioxidant activity  through scavenging free radicals Ùˆ it occurs in several  isomeric forms , these isomers have relatively different functions . One of these actions is related to its ability to inhibit platelets aggregation and hence thrombosis. The present study included a total number of apparently healthy  62 males . 11of them served as standard group , treated  with 100 mg aspirin /day for more than one month . Another 31 subjects were randomly grouped into 5 groups that received different daily doses of α – tocopherol : 400 IU , 800 IU and 1200 IU for  2-6 months.The remainder ( 20 ) subjects served

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Publication Date
Fri Mar 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
Oral health knowledge and practices of women attending dental clinics of Baghdad University
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Background: Knowledge is considered to be essential for developing healthy practices and preventing the main oral diseases. In some developing countries, women were at higher risk to develop these diseases. This study was conducted to evaluate women’s dental knowledge and practices through a specific questionnaire and the relationship with patient’s educational level and the number of their children. Subjects and method: Women, aged from 25-35 years old, were selected to participate in the current study. They were attending dental clinics in the teaching hospital of Baghdad University. Each participant was instructed to answer questionnaire sheet which is previously prepared in Arabic language by the authors. The total numb

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