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Computation of Critical Submergence Depth to Avoid Surface Vortices at Vertical Pumps Intakes
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The pumping station became widely used in many fields. Free surface vortices at intakes of pumps are not favorable. It may cause noise, excessive vibration, damage to the pumping structure, reduction in efficiency and flow for hydro-turbines, etc. One of the important problems encountered during the pump intake design is the depth of submergence and other design parameters to avoid strong free-surface vortices formation. This study aims to compute the critical submergence depth with some geometrical and hydraulic limitations by using Computational Fluid Dynamic (CFD) package. The mathematical model was validated with a laboratory model that had been conducted. The model of three intake pipes was investigated under five different submergence depth (S), three different spaces between intake pipes (b), and five different suction velocities (v). The results showed the best operation cases when the space between intake pipes (b) equal to 4D, the submergence depth of water is equal or greater than 1.25 from the bell mouth diameter of intake pipe (D), and the suction velocity less than 2 m/s. The worst case was when the space between the suction pipe (b) was (2D), in this case, the vortex appeared at submergence depth (S/D = 2) with suction velocity 3 m/s.

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Publication Date
Sun Jan 01 2023
Journal Name
Journal Of The Mechanical Behavior Of Materials
Simulation and assessment of water supply network for specified districts at Najaf Governorate
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Abstract<p>This study aims to simulate and assess the hydraulic characteristics and residual chlorine in the water supply network of a selected area in Al-Najaf City using WaterGEMS software. Field and laboratory work were conducted to measure the pressure heads and velocities, and water was sampled from different sites in the network and then tested to estimate chlorine residual. Records and field measurements were utilized to validate WaterGEMS software. Good agreement was obtained between the observed and predicted values of pressure with RMSE range between 0.09–0.17 and 0.08–0.09 for chlorine residual. The results of the analysis of water distribution systems (WDS) during maximum demand </p> ... Show More
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Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
Design of Optical Fibers and Calculate their Guided Modes Properties at 1550 nm
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Abstract<p>There is no doubt that optical fiber technology is one of the most important stages of the communications revolution at all and it is of utmost importance in our daily life. In this work, five fibers with core radii 2.5, 4.5 and 6.5–8.5 μm were designed. The properties of all guided modes have been calculated at a wavelength of 1550 nm by using RP Fiber Calculator. A single-mode fiber is obtained when the core radius approaches the wavelength. As the core radius is increased, the fiber becomes a multimode. The percentage power in the core increases with increasing core radius. The modes profiles were illustrated and compared with the modern references.</p>
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Publication Date
Mon Jan 01 2024
Journal Name
2nd International Conference For Engineering Sciences And Information Technology (esit 2022): Esit2022 Conference Proceedings
Spectroscopic study of dielectric barrier discharge argon plasma at different gas flow rates
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Dielectric barrier discharges (DBD) can be described as the presence of contact with the discharge of one or more insulating layers located between two cylindrical or flat electrodes connected to an AC/pulse dc power supply. In this work, the properties of the plasma generated by dielectric barrier discharge (DBD) system without and with a glass insulator were studied. The plasma was generated at a constant voltage of 4 kV and fixed distance between the electrodes of 5 mm, and with a variable flow rate of argon gas (0.5, 1, 1.5, 2 and 2.5) L/min. The emission spectra of the DBD plasmas at different flow rates of argon gas have been recorded. Boltzmann plot method was used to calculate the plasma electron temperature (Te), and Stark broadeni

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Influences of the Cu Substitution at Hg Site in Hg1 - xCuxBa2Ca2Cu3O8+δ Superconductors
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The influences of the Cu substitution at Hg site in the HgOd layer, upon the
microstructure, Tc and oxygen content of Hg-1223 have been investigated. High
temperature superconductor with a nominal composition Hg1-xCuxBa2Ca2Cu3O8 + δ for
Cu ( 0 £ x £ 0.5) have been prepared by the two-steps solid state reaction method
under optimum conditions. XRD showed a tetragonal structure with a high ratio of
Hg-1223 superconductor phase. Tc enhancement has been determined with the Cu
concentration was is found to be Tc = 153 K for x = 0.3, while the oxygen content
observed variously with Cu concentration. Hg1-xCuxBa2Ca2Cu3O8+δ structure, oxygen
content and Tc behavior have been discussed.

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Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Effect of electronic governance in Auditing Quality Research applied at the Economic Organization
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The research paper aims to highlight the impact of electronic governance in improving the quality of auditing through accounting disclosure and how to make use out of it in resolving many of the problems by economic units in general and in particular the financial problems in particular. It focuses on the most important financial information of the loss of confidence and credibility in the financial information of the economic units, This study  has  been carried out through the use and application of many of the principles and rules contained in the electronic governance, The most important Which is the accounting disclosure, and hence the dimensions of accounting for electronic governance through the achievement of ac

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Publication Date
Thu Dec 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
E'XCESS VOLUMES OF HEAVY OIL- STOCKS MIXTURES+ (KEROSENE OR XYLENE) AT 3O3 K
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Binary mixtures of three heavy oil-stocks had been subjected to density measurments. The data had been aquired on the volumetric behaviour of these systems. The heavy oil-stocks used were of good varity, namely 40 stock , 60 stock, and 150 stock, 40 stock is the lightest one with the API gravity 33.7 while 60 stock is middle type and 150 stock is heavy one, with API gravity 27.7 and 23.8 respectively. Stocks with Kerosene or Xylene for non-ideal mixtures for which excess volume can be positive or  negative. Mixture of heavy-oil stocks with paraffinic spike (Kerosene) show negative excess volume. While, aromatic rings results a lower positive excess volume, as shown in Xylene when blending with 40 stock and 60 stock but a negati

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Publication Date
Mon Mar 01 2021
Journal Name
Iraqi Journal Of Physics
Studying of Plasma- Polymerized Pyrrole at Variable Gas Flow Rates Via Plasma Jet
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     In this manuscript has investigated the synthesis of plasma-polymerized pyrrole (C4H5N) nano-particles prepared by the proposed atmospheric pressure nonequilibrium plasma jet through the parametric studies, particularly gas flow rate (0.5, 1 and 1.5 L/min). The plasma jet which used operates with alternating voltage 7.5kv and frequency 28kHz. The plasma-flow characteristics were investigated based on optical emission spectroscopy (OES). UV-Vis spectroscopy was used to characterize the  oxidization  state for polypyrrole. The major absorption appears around 464.1, 449.7 and 435.3  nm at the three flow rate of argon gas. The chemical composition and structural properties of the

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Publication Date
Wed Oct 18 2023
Journal Name
Iraqi National Journal Of Nursing Specialties
Assessing Risk Factors of Pneumonia among Adults at Ibn-Sina in Mosul City
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Objectives: the aim of the study to assess the most common risk factors of pneumonia at adult and find the
socio-demographic characteristics of sample.
Methodology: the study performed at Ibn-Sina teaching hospital (intensive care unit) and out patient in the same
hospital period of (15 ) November (2006) till (1ا٤) February (2007).The sample of the study includes (65)
patients with pneumonia for different underlying causes who were attending Ibn-Sina teaching hospital age
range (59-68) years is the highest level and is the most common risk factor for pneumonia.
Results: the results of the study most patients' hospital acquired-pneumonia from contamination during
administration to hospital but community acquired-pne

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Publication Date
Thu Jul 01 2004
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
DETECTION OF SUBSURFACE CAVITIES BY THE ELECTROMAGNETIC METHOD (Case Study at Haditha Area)
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Two EM techniques, terrain conductivity and VLF-Radiohm resistivity (using two
different instruments of Geonics EM 34-3 and EMI6R respectively) have been applied to
evaluate their ability in delineation and measuring the depth of shallow subsurface cavities
near Haditha city.
Thirty one survey traverses were achieved to distinguish the subsurface cavities in the
investigated area. Both EM techniques are found to be successfiul tools in study area.

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Publication Date
Wed Dec 25 2019
Journal Name
Journal Of Engineering
Effect of Tail Regulators on Euphrates River Flood Capacity at Al Nassiriyah City
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Euphrates River extends about 125 km within the study area located in Annassiriyah City, Dhi Qar Governorate, Iraq. The impact of the seven hydraulic structures on the discharge capacity of the Euphrates River needs to be considered. The main objectives of this research are to increase the discharge capacity of Euphrates River within Annassiriyah City during flood seasons and study the impact of these hydraulic structures on the river capacity by using HEC-RAS 5.0.3 software. Five scenarios were simulated to study the different current condition of Euphrates River within Annassiriyah City. Other additional four scenarios were implemented through river training to increase the river capacity to 1300 m³/s; it is the flood

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