Preferred Language
Articles
/
joe-2262
Laminar Free Convection In Horizontal Annulus Filled With Glass Beads And With Annular Fins On The Inner Cylinder
...Show More Authors

An experimental and numerical study has been carried out to investigate the heat transfer by natural convection and radiation in a two dimensional annulus enclosure filled with porous media (glass beads) between two horizontal concentric cylinders. The outer cylinders are of (100, 82 and70mm) outside diameters and the inner cylinder of 27 mm outside diameter with (or without) annular fins attached to it. Under steady state condition; the inner cylinder surface is maintained at a high temperature by applying a uniform heat flux and the outer cylinder surface at a low temperature inside a freezer. The experiments were carried out for an annulus filled with
glass beads at a range of modified Rayleigh number (4.9 ≤ Ra≤ 69), radiation parameter (0<Rd<10), with fin length of (Hf=3, 7 and 11mm), with radius ratios of (Rr=(r1/r2) =0.1405,0.2045, 0.293 and 0.3649 ), number of fins (n=0, 12, 23 and 45). Finite difference method with Boussinesq's approximation is used to solve the continuity, energy and momentum equations.
The numerical solution is capable of calculating the streamline, the temperature field, the velocity field, the local and average Nusselt number. A computer program in Mat lab has been built to carry out the numerical solution. The numerical study was done for a range of modified Rayleigh number (4.9 ≤ Ra ≤ 300). Results show that the average Nusselt number is nearly constant for Ra less than 100 and increased with an increase in modified Rayleigh number.
Nusselt number hardly affected by glass beads size and insignificant affected by Rd for Ra less than 100. Decreasing Rr cause clearly increase in average Nusselt number and increasing fin length or fin number decrease heat transfer.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Mar 13 2019
Journal Name
Al-khwarizmi Engineering Journal
Investigation Microwave Furnace Effects on Mechanical Properties and Fatigue Life of AA 7075-T73 with Dry and Acid Treatments
...Show More Authors

Microwave heating is caused by the ability of the materials to absorb microwave energy and convert it to heat. The aim of this study is to know the difference that will occur when heat treating the high strength aluminum alloys AA7075-T73 in a microwave furnace within different mediums (dry and acidic solution) at different times (30 and 60) minutes, on mechanical properties and fatigue life. The experimental results of microwave furnace heat energy showed that there were variations in the mechanical properties (ultimate stress, yielding stress, fatigue strength, fatigue life and hardness) with the variation in mediums and duration times when compared with samples without treatment. The ultimate stress, yielding stress and fatigue streng

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Distribution of the Infection with Trichomonas vaginalis and Associated Microorganisms in Women Attending Two Hospitals in Al-Sader City, Baghdad
...Show More Authors

  A total  of 320  samples  of vaginal  swabs  was  obtained  from  women complaining of vaginal infection and attending two hospitals in Al-Sader city, Baghdad, namely Ibn AlBaladi Hospital for Pediatrics and Gynecology and Fatimat Al-Zahraa Hospital for Obstetrics in Al-Habibia district during the period from Desember 1997 till July 1998. Results of direct smear and culture showed  that Trichomonas vaginalis infection occurred in 19.1%, in addition to some microorganisms. The most common infection was by Candida spp. (24.7%), followed  by  Gardnerella  vaginalis (13.8%)  and  Staph. aureus  (10.9%). Infection with Escherichia coli, Klebsiella spp. and Prote

... Show More
View Publication Preview PDF
Publication Date
Thu Mar 05 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
Special exercises with ropes, rubber bullets and their impact in some biomechanical variables in the 100m hurdles ran for juniors
...Show More Authors

Publication Date
Fri May 01 2020
Journal Name
International Journal Of Psychosocial Rehabilitation
Special exercises with ropes, rubber bullets and their impact in some biomechanical variables in the 100m hurdles ran for juniors
...Show More Authors

The rubber ropes exercises affected muscle groups, which in turn affects the corners of the conditions of the body before and over the barrier where affected the time passed. To change the angle of the approaching and payment impact on passing each times the barrier 1-5. That passed over the barrier 1and gate 5 impacts on the nature of the achievement, where time has become less. Find the values of cruise missiles and other phases and stages of pitch angle other categories which it enshrines stood as compelling rejection men's 110m hurdles. Find the value of the instant messaging distances between different barriers and stages. Studies by adding rubber sling barriers race categories, measurement of kinematic variables. Emphasis on the devel

... Show More
View Publication
Publication Date
Sun Oct 01 2023
Journal Name
Journal Of Medicine And Life
Evaluating the effect of ursodeoxycholic acid (UDCA) in comparison with dexamethasone and diclofenac in a rat model of rheumatoid arthritis
...Show More Authors

View Publication
Scopus (1)
Scopus Crossref
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The organizational performance of the kindergarten teachers and its relation with the educational environment of kindergartener
...Show More Authors

The research aims at identifying the organizational performance of the kindergarten teachers and defines the educational environment of kindergarten children. To achieve the objectives of the research, the researcher adopted the organizational performance scale for (Saadi, 2016), which was applied to kindergarten teachers. The scale consists of (43) paragraphs, and has good reliability and validity, as the coefficient of reliability (84.0) in a retest method, and (87.0) using the formula Alpha Kronbach. Additionally, the researcher adopted the educational environment scale for (Radam, 2015); the scale consists of (66) paragraphs, and it enjoys a good reliability and validity, as the coefficient of reliability (89.0) method of reliability

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 07 2013
Journal Name
Journal Of Educational And Psychological Researches
Vocational stresses and their relation with the level of ambition among the lecturers of the university
...Show More Authors

Vocational stresses and their relation with the level of ambition among the lecturers of the university In general , vocational stresses affect the attention and the process of focusing making individual busy with solving of his daily problems instead of his job. The vocational stresses , anxiety and tension are factors effecting the physical and psychological ability of the individual. This study aims to measure the vocational stresses among the lecturers of the university , to measure the level of ambition among them, to identify the statistical differences significant among them according to sex variable, to identify the differences significant in level of ambition among them according to sex variable and to identify the correlation r

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Studying of the complexes product of the nerve agent Soman with the Butyrylcholinesterase and Acetylcholinesterase Enzymes
...Show More Authors

Cholinesterases are among the most efficient enzymes known. They are divided into two groups: acetylcholinesterase (AChE) involved in the hydrolysis of the neurotransimitter acetylcholine, and butyrylcholinesterase (BChE) of unknown function. Several crystal structures of the former have shown that the active site is located at the bottom of a deep and narrow gorge. Human BChE has attracted attention because it can hydrolyze toxic esters and nerve agents. Here we analyze the complexes of cholinesterase with soman by describing the 3D geometry of the complex, the active site, the changes happened through the inhibition and provide a description for the mechanism of inhibition. Soman undergoes degradation in the active site of the AChE and B

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Dental Hypotheses
Effect of Dentin Surface Pretreatment With Chitosan Nanoparticles on Immediate and Prolonged Shear Bond Strength of Resin Composite: An in Vitro Study
...Show More Authors

View Publication
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Tue Jan 09 2018
Journal Name
Iraqi Journal Of Cancer And Medical Genetics
Photodynamic Action of low power He-Ne laser on photosensitized human Hep-2 and AMN3 cell lines with Hematoporphyrin derivative in vitro
...Show More Authors

Photodynamic Action (PDA) by using appropriate wavelength of irradiation conjugated with porphyrin derivatives is a powerful mechanism of tumor destruction. Hematoporphyrin derivative has been shown to selectively localize in neoplastic cells and then cause destruction of them by generation of singlet oxygen when activated by low power He-Ne laser. Light which used in this study has been emitting from this laser has a wavelength equal to 632.8 nm (red light). Doses of laser had been varied from 3.6 J/cm2 to 14.4 J/cm2 . The beam of laser adjusted with a modified tissue culture plate. Cell lines had exposed to Hematoporphyrin D (HpD) for 24 hours before Laser exposure, their concentrations were varied from 5 µg/ml to 80 µg/ml. Resu

... Show More
View Publication
Crossref