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Yearly Energy, Exergy, and Environmental (3E) Analyses of A Photovoltaic Thermal Module and Solar Thermal Collector in Series
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The annual performance of a hybrid system of a flat plate photovoltaic thermal system and a solar thermal collector (PVT/ST) is numerically analyzed from the energy, exergy, and environmental (CO2 reduction) viewpoints. This system can produce electricity and thermal power simultaneously, with higher thermal power and exergy compared to conventional photovoltaic thermal systems. For this purpose, a 3D transient numerical model is developed for investigating the system's performance in four main steps: (1) investigating the effects of the mass flow rate of the working fluid (20 to 50 kg/h) on the temperature behavior and thermodynamic performance of the system, (2) studying the impacts of using glass covers on the different parts of the system, (3) evaluating the annual energy and exergy analyses of the system under Mashhad weather conditions, and (4) examining the CO2 reduction by using the proposed system. The results show that for the (glazed) PVT and (glazed) ST systems, increasing the mass flow rate of the working fluid from 20 to 50 kg/h results in 22% and 1.5% improvements in both thermal and electrical power, respectively. However, the thermal exergy of the system decreases by 40.1%. Furthermore, the (glazed) PVT/(glazed) ST systems generate approximately 86% and 264% more thermal power and energy than the PVT/ST systems, respectively. Using a (glazed) PVT/(glazed) ST system with a working fluid’s mass flow rate of 50 kg/h results in maximum thermal and electrical efficiencies of 40.7% and 16.22%, respectively. According to the annual analysis, the highest average thermal and electrical power, equal to approximately 338.3 and 24 W, respectively, is produced in August. The amount of CO2 reduction increases by increasing the mass flow rate and using a glass cover. The PVT/(glazed)ST system has the potential to reduce CO2 emissions by 426.3 kg per year. 

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Publication Date
Fri Oct 16 2026
Journal Name
Journal Of Engineering
Testing and Commissioning of a Low-Speed Wind Tunnel (LSWT) Test Section
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The calibration of a low-speed wind tunnel (LSWT) test section had been made in the present work. The tunnel was designed and constructed at the Aerodynamics Lab. in the Mechanical Engineering Department/University of Baghdad. The test section design speed is 70 m/s. Frictional loses and uniformity of the flow inside the test section had been tested and calibrated based on the British standards for flow inside ducts and conduits. Pitot-static tube, boundary layer Pitot tube were the main instruments which were used in the present work to measure the flow characteristics with emphasize on the velocity uniformity and boundary layer growth along the walls of the test section. It is found that the maximum calibrated velocity for empty test sect

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Publication Date
Thu Jun 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
A PARTICULAR SOLUTION OF THE TWO AND THREE DIMENSIONAL TRANSIENT DIFFUSION EQUATIONS
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A particular solution of the two and three dimensional unsteady state thermal or mass diffusion equation is obtained by introducing a combination of variables of the form,
η = (x+y) / √ct , and η = (x+y+z) / √ct, for two and three dimensional equations
respectively. And the corresponding solutions are,
θ (t,x,y) = θ0 erfc (x+y)/√8ct and θ( t,x,y,z) =θ0 erfc (x+y+z/√12ct)

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Publication Date
Sun Jul 01 2001
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
A new species of Wohlfahrtia Brauer and Bergenstam (Dipetera: Sarcophagidae) from Iraq
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Wohlfahrtia longicorpuris sp. nov., from Iraq described, illustrated and distinguished from related species. The adults were reared from larvae collected from ulcer of a human face. Wohlfahrtia Brauer and Bergenstam is one of most important genus,which contains 19 species (Pape, 1998), some of these produce myiasis in mammals (Verves,1985).Taxonomic revision of this genus has been carried out by the following authors: Rohdendrof (1956), Zumpt (1965) and Pape (1996).

 

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Publication Date
Wed Sep 01 2021
Journal Name
Applications And Applied Mathematics: An International Journal (aam)
Stability and Bifurcation of a Cholera Epidemic Model with Saturated Recovery Rate
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In this paper, a Cholera epidemic model is proposed and studied analytically as well as numerically. It is assumed that the disease is transmitted by contact with Vibrio cholerae and infected person according to dose-response function. However, the saturated treatment function is used to describe the recovery process. Moreover, the vaccine against the disease is assumed to be utterly ineffective. The existence, uniqueness and boundedness of the solution of the proposed model are discussed. All possible equilibrium points and the basic reproduction number are determined. The local stability and persistence conditions are established. Lyapunov method and the second additive compound matrix are used to study the global stability of the system.

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Publication Date
Wed May 24 2023
Journal Name
College Of Islamic Sciences
Manifestation, implicitness, and the interaction of Quranic discourse systems - a stylistic study
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Stylistics represents a modern approach in understanding the literary text through the linguistic patterns that form it. The distinctive phenomena that the text includes constitute special features in it. As well as exploring its aesthetic aspects through description and analysis at the same time. The close link between stylistics and linguistics made stylistics occupy a prominent place in modern literary criticism.
In this regard, we do not want to dwell on the different directions of stylistics. Rather, we will prolong the discussion in the study of the style as a (deviation. Aversion) from the original. Because this trend plays on the chord of the paradox between the surface structure and the deep structure, especially when the sur

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Publication Date
Fri Dec 22 2006
Journal Name
Journal Of Planner And Development
Population growth and urban development (for a number of contemporary Arab cities)
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The aim of the research is to identify the extent of the direct and indirect relationship of the population growth of the cities as a result of the urbanization process witnessed by the Arab region for the urban development of the city structures and their formative structures, changing the planning criteria of some cities and the extent of their changes in spatial and temporal dimensions and their relation to the standards of the western cities. In changing the concept of the modern Arab city, such as the emergence of new functional uses affecting the change in the pattern of formal formations of its urban fabric associated with its ancient morphology and distinctive human nature. The research seeks to identify the extent to which plann

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Publication Date
Tue Jan 01 2019
Journal Name
Iraqi Journal Of Agricultural Sciences
Cloning and expression of a lipase gene from Pseudomonas aeruginosa into E.coli
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Fifteen local isolates of Pseudomonas were obtained from several sources such as soil, water and some high-fat foods (Meat, olives, coconuts, etc.). The ability of isolates to produce lipase was measured by the size of clear zone on Tween 20 solid medium and by measuring the enzymatic activity and specific activity. Isolate M3 (as named in this study) was found to be the most efficient for the production of the lipase with enzymatic activity reached 56.6 U/ml and specific activity of 305.94 U/mg. This isolate was identified through genetic analysis of the 16S rRNA gene. and it was shown that the isolate M3 belongs to Pseudomonas aeruginosa with 99% similarity. The DNA of isolate M3 was extracted and lipase gene was amplified through PCR tec

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Publication Date
Sun Jan 01 2023
Journal Name
Communications In Mathematical Biology And Neuroscience
The dynamics of a delayed ecological model with predator refuge and cannibalism
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This study has contributed to understanding a delayed prey-predator system involving cannibalism. The system is assumed to use the Holling type II functional response to describe the consuming process and incorporates the predator’s refuge against the cannibalism process. The characteristics of the solution are discussed. All potential equilibrium points have been identified. All equilibrium points’ local stability analyses for all time delay values are investigated. The system exhibits a Hopf bifurcation at the coexistence equilibrium, which is further demonstrated. The center manifold and normal form theorems for functional differential equations are then used to establish the direction of Hopf bifurcation and the stability of the per

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Publication Date
Sun Feb 20 2022
Journal Name
Papers In Physics
Electronic and optical properties of nickel-doped ceria: A computational modelling study
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Cerium oxide CeO2, or ceria, has gained increasing interest owing to its excellent catalytic applications. Under the framework of density functional theory (DFT), this contribution demonstrates the effect that introducing the element nickel (Ni) into the ceria lattice has on its electronic, structural, and optical characteristics. Electronic density of states (DOSs) analysis shows that Ni integration leads to a shrinkage of Ce 4f states and improvement of Ni 3d states in the bottom of the conduction band. Furthermore, the calculated optical absorption spectra of an Ni-doped CeO2 system shifts towards longer visible light and infrared regions. Results indicate that Ni-doping a CeO2 system would result in a decrease of the band gap. Finally,

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Publication Date
Sun Sep 29 2024
Journal Name
Pakistan Journal Of Criminology
Artificial Intelligence and Violation of International Human Rights Law: A Dialectical Relationship
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The study explored applications of artificial intelligence and its dialectical relationship with international human rights law of individuals, which requires assessing the effects of this technology on human rights and freedoms. The problem of privacy of humanity, as AI technologies can control human rights and freedoms, while monitoring potential violations in this context. The study use of documentary research and qualitative lens to analyze the data. In conclusion, unawareness of the use of AI may impose significant hurdles on future generations and may infringe on human rights across all sectors of society. The government should mandate obligations for artificial intelligence businesses concerning education, health, human right

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