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Performance Analysis of Four Conceptual Designs for the Air Based Photovoltaic / Thermal Collectors
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The  thermal  and  electrical  performance  of  different  designs  of  air  based  hybrid photovoltaic/thermal collectors is investigated experimentally and theoretically. The circulating air is used to cool PV panels and to collect the absorbed energy to improve their performance. Four different collectors have been designed, manufactured and instrumented namely; double PV panels without cooling (model I), single duct double pass collector (model II), double duct single pass (model III), and single duct single pass (model IV) . Each collector consists of: channel duct, glass cover, axial fan to circulate air and two PV panel in parallel connection. The temperature of the upper and lower surfaces of PV panels, air temperature, air flow rate, air pressure drop, wind speed, solar radiation and ambient temperature were measured. The power produced by solar cells is measured also. A theoretical model has been developed for the collector model IV based on energy balance principle. The prediction of the thermal and hydraulic performance was obtained for the fourth model of PV/T collector by developing a Matlab computer program to solve the numerical model. The experimental results show that the combined efficiency of model III is higher than that of models II and IV. The pressure drop of model III is less than that of models I and IV, by (43.67% and 49%). The average percentage error between the theoretical and experimental results was 9.67%.

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Publication Date
Tue Jun 20 2023
Journal Name
Baghdad Science Journal
Delay differential equation of the 2nd order and it's an oscillation yardstick
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This study focuses on studying an oscillation of a second-order delay differential equation. Start work, the equation is introduced here with adequate provisions. All the previous is braced by theorems and examplesthat interpret the applicability and the firmness of the acquired provisions

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Publication Date
Tue Apr 09 2013
Journal Name
Chemistry And Materials Research
Hydrogen Bonds Effects on the Electrical Properties of Pectin/Pva Graphene Nanocomposites
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Electrical properties were studied for Pectin/PVA graphene composites films and the effect of aqueous interaction on their properties. The conductivity and the dielectric constant of this composite are important because Polysaccharide like pectin is increasingly being used in biomedical applications and as nanoparticles coating materials. The Dielectric and conductivity of composite films were compared in dry and wet condition the differences in the results were attributed to the water molecules and the hydrogen bond which connect the three composite compounds (Pectin, PVA and Graphene) together. These connections were allowed the hydrogen and hydroxyl group’s migrations in the composite super molecules. On the other hand, graphene was pr

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Publication Date
Tue Dec 16 2008
Journal Name
Journal Of Planner And Development
The Role of Islam in Developing Some Basic Concepts in Town Planning
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The arise of Islam as a multidimensional changing phenomenon with its own revolutionary and comprehensive character was inherent with a lot of alterations in social aspects , and this is explicit particularly in the scope of urban life and town planning . Essentially, Islamic style of life has its own urban identity. The urbanization process in Islam has been developed across two integrated sides, the first one concerned on ideational and theoretical aspects , while the other associated with practice .Many urban centers emerged during the Islamic era since the erection of Basrah , the first Islamic town in the middle of the 7th. centaury. Some contemporary urban concepts , both environmental and social could be noticed in Islamic

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Publication Date
Wed Mar 23 2022
Journal Name
Journal Of Educational And Psychological Researches
Self-control and its relation to the work pressure of educational counselors
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1- The degree of self-control of the educational counselors.

2- The level of work pressures that educational counselors are exposed to from their point of view.

3- The significance of the differences in the degree of self-control and work pressures according to the gender variable (male / female).

4- The relationship between self-control and work stress for the sample as a whole.

The current research was limited to educational counselors of both sexes in Anbar Governorate, Ramadi District, affiliated to the Anbar Education Directorate. The researcher adopted the steps of the relational descriptive approach to achieve the research objectives. The current research community consists of (100) m

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Publication Date
Mon Dec 11 2006
Journal Name
Iraqi Journal Of Laser
The Inhibition of Streptococcus mutans by He- Ne Laser via TBO Photosensitizer
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This work aims to investigate the inhibition of vitality of Streptococcus mutans, which is the causative agent of caries. A 632.8 nm He-Ne laser with the output power of 4.5mW was used in combination with toluidine blue O (TBO) at the concentration of 50μg/ml as a photosensitizer. Streptococcus mutans was isolated from 35 patients if carious teeth. Three isolates were chosen and exposed to different energy densities of He – Ne laser light 3.8, 11.7, 34.5 and 104.1 J/cm². After irradiation, substantial reduction was observed in the number of colony forming units (CFU)/ ml. The reduction in the number of CFU was increasing as the dose increased.

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Publication Date
Tue Dec 30 2014
Journal Name
College Of Islamic Sciences
Approaches to the formation of a contemporary explanatory mindset: Critical inductive study
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The issue of the development of Qur'anic studies for the tasks, and the first thought of minds and multiple understandings, and the most precious ideas, and the alternatives were floated, and varied visions, especially as we live in an era exploding knowledge, and complicate secretions, and scramble his ideas, and to devise intellectual approaches To achieve the witnesses of civilization in the words of the Almighty (to be martyrs on the people) Surat Al - Baqarah / 143 attendance and participation in the achievement and a positive interaction with the participants of humanity and civilization in the light of the meaning (to know) rooms / 13.
Therefore, we must emerge from the one-dimensional view of the Koran to the complex mindset t

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Publication Date
Sun Dec 02 2018
Journal Name
Indian Journal Of Public Health Research & Development
A revised checklist of the blister beetles genera (Coleoptera, Meloidae) from Iraq
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Publication Date
Fri Jul 27 2018
Journal Name
Journal Of Biodiversity And Environmental Science
The acute toxicity of herbicide roundup ultra in mosquito fish Gambusia affinis
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Publication Date
Thu Jul 01 2021
Journal Name
Review Of International Geographical Education (rigeo)
Walkability as one of the Planning Treatments to Face Epidemics in Cities
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Walkability as one of the Planning Treatments to Face Epidemics in Cities

Publication Date
Fri Dec 15 2023
Journal Name
Al-academy
The Aesthetics of Lumia Art in Contemporary Textile Arts, An Analytical Study
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The research (The Aesthetics of Lumia Art in Contemporary Textile Arts: An Analytical Study) included four chapters, the first to explain the research problem summarized by the question: Does the art of Lumia achieve aesthetic values in contemporary textile arts?, and aims to: Identify the aesthetics of Lumia art and its applied uses in contemporary textile arts, within the time period (2013-2022). The third chapter included: research procedures and sample analysis (4) models according to the descriptive analytical approach, and the fourth chapter dealt with: results, conclusions and recommendations as well as sources.

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