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The speed, reflection and intensity of waves propagating in flexible tubes with aneurysm and stenosis: Experimental investigation
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A localized stenosis or aneurysm is a discontinuity that presents the pulse wave produced by the contracting heart with a reflection site. However, neither wave speed ( c) in these discontinuities nor the size of reflection in relation to the size of the discontinuity has been adequately studied before. Therefore, the aim of this work is to study the propagation of waves traversing flexible tubes in the presence of aneurysm and stenosis in vitro. We manufactured different sized four stenosis and four aneurysm silicone sections, connected one at a time to a flexible ‘mother’ tube, at the inlet of which a single semi-sinusoidal wave was generated. Pressure and velocity were measured simultaneously 25 cm downstream the inlet of the respective mother tube. The wave speed was measured using the PU-loop method in the mother tube and within each discontinuity using the foot-to-foot technique. The stenosis and aneurysm dimensions and c were used to determine the reflection coefficient ( R) at each discontinuity. Wave intensity analysis was used to determine the size of the reflected wave. The reflection coefficient increased with the increase and decrease in the size of the aneurysm and stenosis, respectively. c increased and decreased within stenosis and aneurysms, respectively, compared to that of the mother tube. Stenosis and aneurysm induced backward compression and expansion waves, respectively; the size of which was related to the size of the reflection coefficient at each discontinuity, increases with smaller stenosis and larger aneurysms. Wave speed is inversely proportional to the size of the discontinuity, exponentially increases with smaller stenosis and aneurysms and always higher in the stenosis. The size of the compression and expansion reflected wave depends on the size of R, increases with larger aneurysms and smaller stenosis.

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Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Engineering
Hydrodesulfurization of Iraqi Atmospheric Gasoil by Ti-Ni-Mo/γ-Al2O3 Prepared Catalyst
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This study investigates the improvement of Iraqi atmospheric gas oil characteristics which contains 1.402 wt. % sulfur content and 16.88 wt. % aromatic content supplied from Al-Dura Refinery by using hydrodesulfurization (HDS) process using Ti-Ni-Mo/γ-Al2O3 prepared catalyst in order to achieve low sulfur and aromatic saturation gas oil. Hydrodearomatization (HDA) occurs simultaneously with hydrodesulfurization (HDS) process. The effect of titanium on the conventional catalyst Ni-Mo/γ-Al2O3 was investigated by physical adsorption and catalytic activity test.Ti-Ni-Mo/γ-Al2O3 catalyst was prepared under vacuum impregnation condition to ensure efficient pr

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Calculations For Sputtering Yield of Nickel Surface Hitted By Xenon Plasma Ions
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Extended calculations for sputtering yield through bombed Nickel – target by Xenon ions plasma are accomplished. The calculations include changing the input parameters: the energy of xenon ions plasma, the hit target angle of nickel target, thickness of the nickel target layer, and the slight change in the surface binding energy of Nickel. The program TRIM is used to accomplish these calculations. The results show that the sputtering yields directly dependent on these parameters. The change in angles of incidence plasma ions and energy leads to a significant change in the sputtering yields. On the other hand, the sputtering yields ore highly affected by changing target width and surface binding energy at fixed ion parameters.

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Publication Date
Thu Jun 30 2011
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
CRACKING ACTIVITY OF PREPARED Y-ZEOLITE CATALYST USING CUMENE ON FLUIDIZED BED REACTOR
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The catalytic activity of faujasite type NaY catalysts prepared from local clay (kaolin) with different Si/Al ratio was studied using cumene cracking as a model for catalytic cracking process in the temperature range of 450-525° C, weight hourly space velocity (WHSV) of 5-20 h1, particle size ≤75μm and atmospheric pressure. The catalytic activity was investigated using experimental laboratory plant scale of fluidized bed reactor.
It was found that the cumene conversion increases with increasing temperature and decreasing WHSV. At 525° C and WHSV 5 h-1, the conversion was 42.36 and 35.43 mol% for catalyst with 3.54 Si/Al ratio and Catalyst with 5.75 Si/Al ratio, respectively, while at 450° C and at the same WHSV, the conversion w

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Publication Date
Fri Nov 15 2024
Journal Name
Iraqi Journal Of Science
Stellar Thermonuclear Reaction Rates of Proton Radiative Capture by Closed Light Shell Isotopes
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Light isotopes, especially closed shell nuclei, have significance in thermonuclear reactions of the Carbon-Nitrogen-Oxygen (CNO) cycle in stars. In this research, 12C(p, γ) 13N and 14N(p, γ) 15O reactions have been calculated by means of Matlab codes to find the reaction rate across a temperature range of 0.006 to 10 GK using non-resonant parts, as well as the astrophysical S- factor S(E) at low energies. It was concluded that the high binding energy of 12C and 14N nuclei make the reaction less probable thus enabling other competitive processes to develop, which enhances the probability of other competitive proton reactions in the CNO cycle.

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Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Extraction of Penicillin V from Simulated Fermentation Broth by Liquid-Liquid Membrane Technique
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Liquid-liquid membrane extraction technique, pertraction, using three types of solvents (methyl isobutyl ketone, n-butyl acetate, and n-amyl acetate) was used for recovery of penicillin V from simulated fermentation broth under various operating conditions of pH value (4-6) for feed and (6-8) for receiver phase, time (0-40 min), and agitation speed (300-500 rpm) in a batch laboratory unit system. The optimum conditions for extraction were at pH of 4 for feed, and 8 for receiver phase, rotation speed of 500 rpm, time of 40 min, and solvent of MIBK as membrane, where more than 98% of penicillin was extracted. 

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Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
External Morphological Study of Diplacodes Triviales Rambure(Odonata :Libellulidae)New Record to Iraq
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External Morphologicalstudy of species DiplacodestrivialesRambure of family :
Libellulidae from suborder Anisoptera of the order Odonata which were collected from
Maisan Governorate 2010.
such study was included : Detailed description of most body parts (Head,
Thorax,Abdomen and their appendages), identification and recognition of species, study male
and female genitalia. The species Diplacodes Triviales Rambure was new record to Iraqi
fauna of Odonata.

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Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Fractional Free Volume Dependence of Neutron-Irradiated Polystyrene (PS) Measured by Positron Method
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The fractional free volume (Fh) in polystyrene (PS) as a function of neutron -irradiation dose has been measured, using positron annihilation lifetime (PAL) method. The results show that Fh values decreased with increasing n-irradiation dose up to a total dose of 501.03× 10-2 Gy.
A percentage reduction of 2.14 in Fh values is noticed after the initial n-dose corresponding to a percentage reduction in the free volume equal to 42.14/Gy.
The total n-dose induces a percentage reduction of 7.26, corresponding to a percentage reduction of 1.45/Gy. These results indicate that cross -linking is the predominant process induced by n-irradiation.
The results suggest that n-irradiation induces structure changes in PS, causing cross-linking

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Publication Date
Wed May 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Corrosion control of Buried Low Carbon Steel Structure by Using Alteration Medias method
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Abstract

The aim of the present work is to control of metal buried corrosion by alteration the media method. This method depended on the characteristics of each media. The corrosion rates in different media (soil, sand, porcelanite stone and gravel) for specimens of low carbon steel were measured by two methods weight loss method and polarization method, weight loss measured by buried specimens in these medias separately for 90 days. The polarization method includes preparing of specimen and salt solutions have electrical resistivity equivalent electrical resistivity of these media. The corrosion rate of two method results in (soil > sand> porcelainte stone> gravel). The lower corrosion rate happene

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Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
Design of New Hybrid Neural Controller for Nonlinear CSTR System based on Identification
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This paper proposes improving the structure of the neural controller based on the identification model for nonlinear systems. The goal of this work is to employ the structure of the Modified Elman Neural Network (MENN) model into the NARMA-L2 structure instead of Multi-Layer Perceptron (MLP) model in order to construct a new hybrid neural structure that can be used as an identifier model and a nonlinear controller for the SISO linear or nonlinear systems. Two learning algorithms are used to adjust the parameters weight of the hybrid neural structure with its serial-parallel configuration; the first one is supervised learning algorithm based Back Propagation Algorithm (BPA) and the second one is an intelligent algorithm n

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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Engineering Science And Technology (jestec)
Optimum Operation Management Effect of Main Sewage Pumping Stations on Trunk Sewer Deterioration
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Sewage pumping stations are considered an important part of any sewerage system. Pumps failure in these stations means that the pumps are unable to work at the design requirement (flow capacity and head) and that may cause sewer overflow and flooding leading to sewer deterioration. In this paper, two main sewage pumping stations in Baghdad city were selected as case studies, Al- Habibia and Al-Ghazali located on Zublin trunk sewer 3000 mm and Baghdad trunk sewer 1200-2100 respectively. This study focused mainly on the operation of main sewage pumping stations and their effect, both directly and indirectly, on changing hydraulic properties, which leads to an increase in the deterioration of sewage pipes. The hydraulic analysis was co

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