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Numerical Simulation of Temperatures Distribution and Residual Stresses of High Melting Temperature Polymer

This work predicts the effect of thermal load distribution in polymer melt inside a mold and a die during injection and extrusion processes respectively on the structure properties of final product. Transient thermal and structure models of solidification process for polycarbonate polymer melt in a steel mold and die are studied in this research. Thermal solution obtained according to solidify the melt from 300 to 30Cand Biot number of 16 and 112 respectively for the mold and from 300 to 30 Cand Biot number of 16 for die. Thermal conductivity, and shear and Young Modulus of polycarbonate are temperature depending. Bonded contact between the polycarbonate and the steel surfaces is suggested to transfer the thermal load. The temperatures distribution produces in thermal model importing as load and boundary conditions to solve the structure model. 3D mold and die are built to simulate the thermal and structure behavior using ANSYS 12.1 program. The results show that the temperatures and residual stresses decreases with the distance from the center to surfaces for the mold ,while for the die the temperatures and stresses decreases with the distance from the inlet to the outlet. The temperatures and stresses decreases with the time increasing for both mold and die. Also the thermal strain compatible with the temperatures distribution in the mold and the die. The total deformation concentrated at the left and right edge of polycarbonate in the mold, while starting in the center of the polymer at the outlet and then transfer to the entry of the die with the time increasing.

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Hybrid(Luminescent and Fresnel ) Concentrators to Improve Solar Panel Conversion Efficiency

The spectral response of the Si solar cell does not coincidence with the sun irradiance spectrum, so the efficiency of the Si solar cell is not high. To improve the Si solar cell one try to make use of most region of the sun spectrum by using dyes which absorb un useful wavelengths and radiate at useful region of spectrum (by stock shift). Fluorescence's dye is used as luminescent concentrator to increase the efficiency of the solar cell. The results show that the performance efficiency and out power for crystalline silicon solar cells are improved.

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Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
Parabola Dish and Cassegrain Concentrators to Improve Solar Cell Conversion Efficiency

New designs of solar using ray tracing program, have been presented for improved the performance and the out put power of the silicon solar cell, as well as reducing the cost of system working by solar energy. Two dimensional solar concentrator (Fresnel lenses) and three dimensional concentrators (parabola dish and cassegrain) were used as concentrator for photovoltaic applications (CPV). The results show that the performance efficiency and out power for crystalline silicon solar cells are improved.

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Publication Date
Fri Jan 01 2016
Journal Name
World Journal Of Experimental Biosciences
Detection of anti-Helicobacter pylori antibodies in sera of women with recurrent spontaneous abortion

To determine the relationship between Helicobacter pylori infection and reproduction disorder (recurrent spontaneous abortion), twenty women patients who undergo spontaneous abortion during first trimester of pregnancy (20-38) years and have been investigated from 2015/12/1 -2016/3/1 and compared to fifteen healthy individuals. All subjects were carried out to measure anti-H. pylori IgA and anti- H. pylori IgG antibodies by enzyme linked immunosorbent assay (ELISA). There was significant elevation (p≤ 0.05) in concentration of anti- H. pylori IgG Abs (6.30± 0.99) compared to control group (4.48± 0.61) and IgA Abs (5.42 ± 0.90 U /ml) as compared to control group (3.92 ± 0.41 U/ml). The percentage of H. pylori IgG and IgA was 20% and 25

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Publication Date
Tue Nov 09 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Tasks Implemented by Internal Auditors when Developing and Executing Business Continuity and Recovery Plan to Face the COVID-19 crisis

The current research aimed to identify the tasks performed by the internal auditors when developing a business continuity plan to face the COVID-19 crisis. It also aims to identify the recovery and resuming plan to the business environment. The research followed the descriptive survey to find out the views of 34 internal auditors at various functional levels in the Kingdom of Saudi Arabia. Spreadsheets (Excel) were used to analyze the data collected by a questionnaire which composed of 43 statements, covering the tasks that the internal auditors can perform to face the COVID-19 crisis. Results revealed that the tasks performed by the internal auditors when developing a business continuity plan to face the COVID-19 crisis is to en

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Publication Date
Sun Sep 02 2012
Journal Name
Baghdad Science Journal
Study Of Factors Affecting The Thermal Conductivity Of Iraqi Bentonite

Thermal conductivity of compacted bentonite is one of the most important properties where this type of clay is proposed for use as a buffer material. In this study, Lee's disc method was used to measure the thermal conductivity of compacted bentonite specimens. The experimental results have been analyzed to observe the three major factors affecting the thermal conductivity of bentonite buffer material. While the clay density reaches to a target value, the measurement is taken to evaluate the thermal conductivity. By repeating this procedure, a relationship between clay dry density and thermal conductivity has been established in specimens after adjusting the water contents of the bentonite by placing its specimens in a drying oven for diffe

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Publication Date
Sun Jan 01 2017
Journal Name
Iraq Journal Of Agricultural Research
Publication Date
Mon Dec 30 2019
Journal Name
College Of Islamic Sciences
The mother of the believers, the mother of Salamah and her narrators of jurisprudence In attaining the goal of the rulings evidence Ibn Hajar al-Asqalani (d. 852 AH)      (prayer book)

The Muslim woman actively participated in narrating, preserving, controlling and maintaining the hadith, along with her brother, the man who later became an inexhaustible representative of the effort to preserve, control, and narrate the Sunnah. Undoubtedly, the mothers of the believers, may God be pleased with them, had a great advantage in communicating Islam and spreading the Sunnah of the Prophet Especially among women, all of them heard from him, may God’s prayers and peace be upon him, and lived with him in the details of his life on the disparity between them in memorizing and narrating and publishing them. It narrated (378) recently, and it is considered the second narrator after the mother of the believers Aisha, may God be pl

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Publication Date
Mon Dec 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Banking Governance According to the principles of the Basel Committee and its impact on the achievement of the strategic objectives of banks Study in a sample of private commercial banks Iraqi

     This study aims to impact statement played by banking governance according to the decisions of the Basel Committee in achieving the strategic objectives of the banks, But order to achieve the this goal has been the adoption of two hypotheses in addition to the two main hypotheses as sub answered preliminary The study seeks to verify their health and two (no correlation relationship and impact between Banking  governance and achieve strategic objectives), has been tested hypotheses. Study has reached

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Publication Date
Sun Dec 06 2009
Journal Name
Baghdad Science Journal
Study of Stability of Personal Dosimeter

The study is carried out by using personal dosimeters (film badge). The films are irradiated to absorbed dose of range (0.01-10000 rad). The calibration curves are drawn by using the ordinary method taking into account the filtration effects in three regions (D (Pb/Sn),D(Du),D(300). The calibration films are stored in ambient condition. It is found that the optical density increases, which is attributed to the photodegradation of the films may induce localized states in the energy gap causing increasing in optical absorption, but optical density decreases, which attributed to the photodegradation of the films may cause some cracks at the film surface during the first month, whereas at the rest months we see clear stability in optical d

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study the effect of acid immersion on the hardness of (Epoxy – Granite) composite

This work has been done with using of epoxy resin mixed with Granite powder were weighted by percent volume (5,10,15, and 20)%and then mixed with epoxy polymer to compose polymer composite. Hand lay-up technique is used in fabrication of the composite samples. Hardness test was carried out for the proper samples in both normal condition and after immersion in HCL (1 M and 2 M) solutions for periods ranging up to 10 weeks. After comparing the results between the polymer and their composite, the hardness increased with increasing Granite weight percent, it was found that Hardness were greater for the composites before immersion compared with their values after immersion.

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