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Mechanical Integrity of Printed Circuit Heat Exchanger
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The printed circuit heat exchanger is a plate type heat exchanger with a high performance and compact size. Heat exchangers such as this need a unique form of bonding and other techniques to be used in their construction. In this study, the process of joining plates, diffusion bonding, was performed and studied. A special furnace was manufactured for bonding purposes. The bonding process of copper metal was carried out under specific conditions of a high temperature up to 700 oC, high pressure of 3.45 MPa, and in an inert environment (Argon gas) to make tensile samples. The tensile samples are cylindrical shapes containing groves representing the flow channels in the printed circuit heat exchanger and checking their tensile strength in addition to the standard shape of the tensile specimen to check the yield and ultimate strength of the copper. A higher tensile strength was obtained for diffusion bonded specimens than the yield strength of copper, up to 1.35 times the copper yield strength. The tensile strength decreases with the increase in the number of groves and the decrease in the distance between one grove and another. This is because the stress is concentrated in the sharp corners. A prototype heat exchanger of two plates and a header to be tested for its compressive strength was also manufactured. The results showed that the bond bears an air pressure of up to 8 bar without fail. It was also found to withstand a hydraulic pressure of up to 60 bar until it reached failure.

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Publication Date
Wed Apr 11 2007
Journal Name
Journal Of Al-nahrain University
KINETICS AND MECHANISM STUDIES OF OXIDATION OF Α-AMINO ACIDS BY N-BROMOSUCCINIMIDE
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Kinetics and mechanism studies of oxidation of some α-amino acids (Proline, Arginine, Alanine) (AA) by N-Bromosuccinimide (NBS) by using conductivity method was carried out. The kinetic study showed that the reaction was first order with respect to NBS and AA. The effect of addition of HClO4 to the reaction was negative on the rate of reaction. The reaction was carried out at different temperatures in which  * * *   , S , G were calculated. The rate of reaction of AA was as follows: Proline > Arginine > Alanine

Publication Date
Sun Dec 01 2024
Journal Name
Journal Of Kufa For Chemical Sciences
Review Article: The Biochemical Role Of Environmental Pollution In The Etiology Of Endometriosis
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Endometriosis is an estrogen dependent inflammatory disorder plays a pivotal role in the reproductive system of the females which regarded as one of the most important gynecological disorders due to it is a key cause of infertility for women and also it has a remarkable impact on the women's life quality. Indeed, environmental pollution have an extremely importance in the etiology of endometriosis. Hence, the present article submits an abbreviated literature review to the biochemical role of environmental pollutants in the etiology and development of endometriosis. Anyway, this review article represented the major environmental pollutants: the organic pollutants of air, heavy metals, gaseous pollutants and the particulate matter. Th

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Publication Date
Sun Jul 01 2012
Journal Name
Baghdad University College Of Education Ibn Al-haitham
Numerical Solution of Linear System of Fredholm Integral Equations Using Haar Wavelet Method
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The aim of this paper is to present the numerical method for solving linear system of Fredholm integral equations, based on the Haar wavelet approach. Many test problems, for which the exact solution is known, are considered. Compare the results of suggested method with the results of another method (Trapezoidal method). Algorithm and program is written by Matlab vergion 7.

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Publication Date
Sun Mar 31 2013
Journal Name
Inventi Impact: Artificial Intelligence
SIMULATION OF IDENTIFICATION AND CONTROL OF SCARA ROBOT USING MODIFIED RECURRENT NEURAL NETWORKS
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This paper presents a modified training method for Recurrent Neural Networks. This method depends on the Non linear Auto Regressive (NARX) model with Modified Wavelet Function as activation function (MSLOG) in the hidden layer. The modified model is known as Modified Recurrent Neural (MRN). It is used for identification Forward dynamics of four Degrees of Freedom (4-DOF) Selective Compliance Assembly Robot Arm (SCARA) manipulator robot. This model is also used in the design of Direct Inverse Control (DIC). This method is compared with Recurrent Neural Networks that used Sigmoid activation function (RS) in the hidden layer and Recurrent Neural Networks with Wavelet activation function (RW). Simulation results shows that the MRN model is bett

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Publication Date
Fri May 15 2026
Journal Name
Research Journal Of Pharmacy And Technology
Ex vivo study of anti-leishmanial activity of artemisinin against Leishmania tropica amastigote
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Leishmania parasites are the causative agent of leishmaniasis. Many studies are inspecting chemical drugs, including the use of miltefosine and amphotericin B, but curative values may be limited for these drugs with side effects due to the chemical origin, therefore, investigating less toxic therapies is essential. The aim of this study was to investigate the effectiveness of artemisinin on Iraqi strain of Leishmania tropica, by experimental macrophage ex vivo infection of amastigotes into mouse macrophage cell-line RAW264.7. Different concentrations (100, 200, 300, 400, 500)μM of artemisinin (ART) were screened to examine the susceptibility of L. tropica amastigotes to invade macrophage cell line along three times of follow up (24, 48 and

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Publication Date
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The Appropriateness Of The Iraqi Environment For Establishment Of Hedge Funds In Iraq
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المستخلص

يهدف البحث إلى وضع إطار معرفي ومفاهيمي شامل لموضوع البحث, واغناء القارئ والمستفيد بالمعلومات الوافية عنه وتقليص الفجوات المعرفية للمهتمين به وقياس مدى ما هو متوفر وغير متوفر من المتطلبات الأساسية والضرورية لإنشاء صناديق التحوط في البيئة العراقية, وتمثلت صناديق التحوط بالمتغير الرئيس للبحث اما المتغيرات الفرعية فشملت (المتطلبات المالية, المتطلبات البشرية, البيئة التشريعية, الب

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Publication Date
Fri May 15 2026
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Temperature and Frequency on the Dielectric Properties of PVC/MnCl2 Composite
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Publication Date
Wed Jul 24 2024
Journal Name
Annals Of Parasitology
In vitro efficacy of different concentrations of lupeol on old world Leishmania donovani
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Leishmaniosis is a tropical neglected parasitic disease that is endemic in many countries, including Middle East, with no existing effective vaccines. The bite of female sand-fly transmits the causative agent, Leishmania spp., to humans. High toxicity, resistance and treatment failure of the available chemotherapy against visceral leishmaniosis demands the investigation of new anti-leishmanial compounds. Lupeol is a form of triterpene isolated from several medicinal plants and possesses an antimicrobial property. In this study, cytotoxic effect of lupeol was screened against the mammalian amastigotes form and insect promastigote form of Leishmania donovani, following three cycles of incubation at different concentrations by MTT assay. Resul

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Publication Date
Tue Aug 03 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The relationship of the investment environment with the indicators of the national economy
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The investment environment is the incubator for all types of domestic and foreign investments, so if their determinants are encouraging, they increase the levels of investment flows and vice versa, as there is a relationship between the nature of the investment environment and the level of investment flows, and the determinants of the investment environment are numerous and the most important of which are security and political stability, and economic and financial factors that include relative stability In the exchange rate and inflation rates, the availability of banks and their development, transparency and integrity in administrative dealings and the lack of prevalence of administrative and financial corruption, and the clari

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Publication Date
Fri May 15 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of different polishing systems on the surface roughness of full-contour zirconia
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Background: Adjustment of any premature occlusal contact of any zirconia restoration requires its polishing or glazing in order to restore the smoothness of the restoration. The objective of this in vitro study was to evaluate the effects of different polishing systems and glazing on the surface roughness of full-contour zirconia. Material and methods: Forty disks (diameter: 8 mm, thickness: 6.4 mm) were prepared from pre-sintered full-contoured zirconia block; they were colored and sintered in a high-temperature furnace at 1500ËšC for 8 hours. The specimens were then leveled and finished using grinding and polishing machine and adjusted using diamond disk. The specimens were then randomly divided into four groups (n=10), group I involves

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