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joe-2070
Evaluation of Convective Heat Transfer and Natural Circulation in an Evacuated Tube Solar Collector
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The evacuated tube solar collector ETC is studied intensively and extensively by experimental and
theoretical works, in order to investigate its performance and enhancement of heat transfer, for Baghdad climate
from April 2011 till the end of March 2012. Experimental work is carried out on a well instrumented collector
consists of 16 evacuated tubes of aspect ratio 38.6 and thermally insulated tank of volume 112L. The relation
between convective heat transfer and natural circulation inside the tube is estimated, collector efficiency, effect of
tube tilt angles, incidence angle modifier, The solar heating system is investigated under different loads pattern (i.e
closed and open flow) to evaluate the heat loss coefficient from tank and tubes, test the collector with various
aspect ratios (32.9 and 27.2). The enhancement in collector performance is studied by using two reflectors (Flat
Plate and Curved Plate) and nanofluid (Water-AL2O3).Theoretical work is run by software (Fluent 6.3), to compute
the velocity and temperature profiles within the tube, for different tube diameters, effect of tube junction angle and
stagnant region in the bottom of the evacuated tube. The experimental results shows that the heat loss coefficient
for tube is W/m2.K and for tank is W/m2.K, the maximum collector temperature is 79°C in winter and
99°C in summer, while that belong to nanofluid collector is 99°C in winter. The best tilted angle (optimum) of
evacuated tube is 41° annually. The collector efficiency increased when using nanofluid of (1, 0.6, 0.3)% volume
fraction as(28.4, 6.8, 0.6)% respectively. The efficiency decreases as (33, 62)% when decreasing tube aspect ratio
from 38.6% to 32.9% and 27.2% respectively. An increase of (16.9 and 7.08)% in collector efficiency is obtained
when using curved and flat plate reflectors respectively. From simulation the best junction angle of the tank is
22.5°. The stagnant region is influenced with changing heat flux, tilted angle and aspect ratio.

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Publication Date
Wed Dec 31 2008
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Bio Chemical Study of Antithyroid Peroxidase Auto Antibodies , Magnesium and Cobalt in Hyperthyroidism Patients From Different Regions of Iraq.
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Publication Date
Mon Jan 01 2018
Journal Name
Front Public Health
Association of Cytochrome CYP1A1 Gene Polymorphisms and Tobacco Smoking with the Risk of Breast Cancer in Women from Iraq
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Background: CYP1A1 gene polymorphisms and tobacco smoking are among several risk factors for various types of cancers, but their influence on breast cancer remains controversial. We analyzed the possible association of CYP1A1 gene polymorphisms and tobacco smoking-related breast cancer in women from Iraq. Materials and methods: In this case-control study, gene polymorphism of CYP1A1 gene (CYP1A1m1, T6235C and CYP1A1m2, A4889G) of 199 histologically verified breast cancer patients' and 160 cancer-free control women's specimens were performed by using PCR-based restriction fragment length polymorphism. Results: Three genotype frequencies (TT, TC, and CC) of CYP1A1m1T/C appeared in 16.1, 29.6, and 54.3% of women with breast cancer, respectiv

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Scopus (17)
Scopus
Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Analysis of actuarial experience and acceptance of individual life insurance: A case study in the Iraqi General Insurance Company
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This research seeks through the adoption of two basic variables, where he considered the actuarial experience as an independent variable, while the process of accepting the risk and dimensions related to it is a dependent variable, the research was adopted to present the data achieved by the company during the life insurance business during the adoption of actuarial experience at the beginning of its work where Adoption of the historical method in the analysis of those data to prove the researcher's opinion, through the analysis of data (5 years) for the first period, which extends between (1975-1979), the period during which the company adopted the actuarial experience at the time, also taken data for the same dimensions related to the

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Publication Date
Tue Mar 10 2026
Journal Name
Journal Of Physical Education
Analytical study of Spiking and Its relation With Tactical Performance of Blockers in Iraqi Volleyball Primer League (2020 – 2021)
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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
" The role of applying the international standards of the Supreme Audit Institutions in achieving administrative reform and improving performance "
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Abstract

The aim of the research is to introduce the international standards of the Supreme audit Institutions, as well as the role of these standards in achieving administrative reform and improving the performance of the Supreme audit Institutions and the performance of the economic units under its control.

In order to achieve the objectives of the research, a questionnaire was designed from two main axes that included a number of questions addressed to a number of officials and employees of the Supreme Audit Institutions and its affiliated bodies on the role of applying the international standards of the Supreme Audit Institutions in achieving administrative re

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Publication Date
Tue Jul 11 2023
Journal Name
Sport Tk-revista Euroamericana De Ciencias Del Deporte
Analysis of the amount of lost fluids, some blood components and mineral salts in volleyball under hot weather conditions
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The research objective was to study the amount of lost fluids, some blood components and mineral salts in volleyball players under hot weather conditions. The sample of the present study was composed of 12 volleyball players of Al-Sinaa Club (Baghdad, Iraq) in the 2022/2023 season. The variables analyzed in this study were: Heart rate before and after exercise, internal and external body temperature before and after exertion, potassium ion, sodium ion, calcium ion, and the amount of fluid lost (the player's weight) before and after the exercise. The tests were conducted at a temperature between 42-47 degrees Celsius. The maximum anaerobic exercise was performed with volleyball. The results showed that to play volleybal

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Publication Date
Sun Jan 01 2023
Journal Name
The Egyptian Journal Of Hospital Medicine
Assessment of Plasma Jet Therapy of Tooth Root Canal Infected with Escherichia Coli and Enterococcus Faecalis Biofilm In Vitro
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Background: Common and persistent isolate ina the teeth following failed therapy of the root canal is the gram-positive facultative bacterium Enterococcus faecalis and Escherichia coli, which develop biofilm through a complicated process that results in the formation of a biofilm. Enterococcus faecalis and Escherichia coli are significant factors that cause chronic periradicular lesions after root canal therapy. Aim: This study aimed to treat the root canal tooth infected with Escherichia coli and Enterococcus faecalis Methods: In this study biofilm formation was done for Escherichia coli in growth phase cultured in a brain heart broth Enterococcus faecalis and Escherichia coli cultured in Luria-Bertani (LB) infusion medium for 18 hrs. Then

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Crossref
Publication Date
Wed Jun 26 2024
Journal Name
Opera Medica Et Physiologica
The Impact of Global DNA Methylation and Hypoxia-Inducible Factor 1 Alpha Levels in the Progression of Breast Cancer
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Scopus (1)
Scopus
Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
The Aqueous Crude Extract of Carrot Seeds ( Daucus carota L.) and it Role in Fertility of Male Albino Mice
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This study was designed to test the effect of the treatment with aqueous extract of carrot seeds( Daucus carota) on fertility of male albino mice by effected on Body weight , testis weight ,secondary sex organs (prostate , seminal vesicle) and sperms properties .This experiment used (24) albino male mice aged(8-10)weeks. these animals were randomly divided into three groups contain two doses (200,400mgkg) were used from both extracts ,they were daily and orally given for (35)days ,and control group was given physiological saline. After the end of the experiment the animals were sacrificed after taken their body weights. The results were show: 1. A significant (p<0.05) increase in body weight and reproductive organs. 2

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Crossref
Publication Date
Sun May 02 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Enhancing Auditor Reporting In Light Of International Assurance Standards And Their Reflection On Activating The Credibility Of Sustainability Reports
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The Assurance Services Are Represented By Expressing A Clear And Independent Opinion On All Financial And Non-Financial Information, As It Is Broader Than The Services Related To Auditing Financial Statements And Expressing Opinion (Certification) And Extends Them To A Wider Range, And It Is Possible To Distinguish Between Auditing And Certification Services And Confirming That Audit Services Relate To Expressing Opinion On Financial Statements And Certification Services Related To By Expressing An Opinion On A Wide Range Of Financial Information And More Broadly Than The Financial Statements And Assurance Services That Include Expressing An Opinion On Integrated Financial And Non-Financial Information And From This Standpoint Came The I

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