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alkej-128
Effect of Journal Misalignment on the Static Characteristics of Porous Journal Bearings Lubricated with Couple Stress Fluid
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In this paper, a theoretical study to the effect of journal misalignment on the static characteristics of oil filled porous journal bearing when lubricated with couple stress fluid has been carried out.

The analytical model used through this work is for a bearing with isotropic permeability. Considering isotropic permeability the Reynolds' equation for the oil film is modified to include a so – called filter term and the effect of fluid coupled stress. The pressure equation for the porous medium is obtained from Darcy's law and continuity equation. The equation which was used to evaluate the oil film thickness was modified to include the effect of possible misalignment in longitudinal and transverse directions. The governing equations with appropriate boundary conditions are numerically solved using a suitable numerical technique. A computer program has been prepared to solve the governing equations. The validity of the program has been tested by comparing the results obtained through this work with that published in  available works. The comparison shows a good agreement between the results obtained through this work and that published by other workers.        

By comparing the behavior of aligned and misaligned bearing it was found that the journal center misalignment has a considerable effect on the performance parameters of the bearing which can not be neglected.

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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
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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

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Crossref
Publication Date
Wed Oct 01 2014
Journal Name
Iosr Journal Of Mathematics
Flow through an Oscillating Rectangular Duct for Generalized Oldroyd-B Fluid with Fractional Derivatives
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The analytic solution for the unsteady flow of generalized Oldroyd- B fluid on oscillating rectangular duct is studied. In the absence of the frequency of oscillations, we obtain the problem for the flow of generalized Oldroyd- B fluid in a duct of rectangular cross- section moving parallel to its length. The problem is solved by applying the double finite Fourier sine and discrete Laplace transforms. The solutions for the generalized Maxwell fluids and the ordinary Maxwell fluid appear as limiting cases of the solutions obtained here. Finally, the effect of material parameters on the velocity profile spotlighted by means of the graphical illustrations

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Publication Date
Wed Mar 02 2022
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of a Training Program to Improve some Aspects of Sensory Integration Disorder and Its Effect on Self-Direction Among a Sample of Children with Intellectual Disabilities
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The present research was conducted to investigate the effectiveness of a training program to improve some aspects of sensory integration disorder and its effect on self-direction among a sample of children with intellectual disabilities. The study sample consists of (10 subjects as an experimental group) were exposed to the training program، and the control group consists of (10 subjects as a control group) were not exposed to the training program. The study included the following tools: A scale of self-direction for intellectual disability (prepared by the researcher). Training program (prepared by the researcher). The Results of the study showed the following: There are no statistically significant differences between the means ranks

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Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
The nonlinear optical properties of Epoxy/Alumina Nanocomposites
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Linear and nonlinear optical properties of epoxy/ Al2O3 nanocomposites system were studied for epoxy neat and (0.5, 1.5, 3, and 5) % Al2O3 nanocomposites.The band gap of epoxy and its nanocomposites was obtained at these weight ratios. Nonlinear optical properties experiments were performed using Q-switched Nd:YAG laser z-scan system.These experiments were carried out for different parameters: wavelengths (1064 nm and 532 nm), laser intensities (0.530, 0.679, and 0.772) GW/cm2 and weight ratio of Al2O3 nanocomposites. The results showed that the band gaps were decreased with increasing the weight ratio of nanoalumina except at 5wt% and the nonlinear refractive index coefficient is directly proportional to the incident intensities while o

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Publication Date
Tue May 28 2019
Journal Name
Al-khwarizmi Engineering Journal
Treatment of Waste Extract Lubricating Oil by Catalytic Cracking Process to Produce Light Fractions
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The catalytic cracking of three feeds of extract lubricating oil, that produced as a by-product from the process of furfural extraction of lubricating oil base stock in AL-Dura refinery at different operating condition, were carried out at a fixed bed laboratory reactor. The initial boiling point for these feeds was 140 ºC for sample (1), 86 ºC for sample (2) and 80 ºC for sample (3). The catalytic cracking processes were carried out at temperature range 325-400 ºC and initially at atmospheric pressure after 30 minutes over 9.88 % HY-zeolite catalyst load. The comparison between the conversion at different operating conditions of catalytic cracking processes indicates that a high yield was obtained at 375°C, according to gasoline pr

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Knowledge Upgrading on Business Continuity:A Field Research in Private Colleges and Universities in Baghdad
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The research aims to study the effect of knowledge upgrade on business continuity in private colleges and universities in Baghdad. The research problem is summarized in the main question (were the academic leaders able to employ knowledge upgrading to enhance business continuity). The most important of this sector were the universities and the private college in the city of Baghdad as a field for this research, the researchers conducted a field visit to (10) universities or private colleges, the research sample consisted of (177) individuals from the deans of colleges and their assistants, as well as heads of scientific and administrative departments. The data was analyzed and the hypotheses were tested using the appropriate statistical

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Crossref
Publication Date
Sat Feb 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Effect of Job Burnout on Employee Performance: Field Research in the General Company for Vegetable Oil Industry
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Abstract

      This research aims to know the effect of job burnout in the worker’s performance. The researcher presented a theoretical basis for job burnout and the worker's performance. In order to achieve the objectives of the research, a hypothesis was drawn up that determines the nature of the relationship between the independent variable of job burnout and its dimensions (reduced personal accomplishment, depersonalization, Emotional Exhaustion) and variable dependent performance of workers dimensions (productivity, job satisfaction, organizational commitment, creativity), And to represent the volume of this community according to (de Morgan, D. Morgan) glo

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Crossref
Publication Date
Fri Dec 01 2023
Journal Name
Baghdad Science Journal
Effect of COVID-19 on the Role of Renin Enzyme and ACE2 and Hormones in PCOS Females
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Polycystic ovary syndrome (PCOS) is the most endocrine problem in women of regenerative age. PCOS women typically belong to an age and sex group which is at higher risk for severe coronavirus disease (COVID-19). COVID-19 targets cells through angiotensin-converting enzyme 2 (ACE2) receptor presents on cells in veins, lungs, heart, digestion tracts, and kidneys. Renin-Angiotensin System (RAS) over activity has likewise been described in metabolic disorders; type 2 diabetes mellitus (T2DM), and conditions shared by women with polycystic ovary condition. The point of this study is to know the job of renin and ACE2 in PCOS and coronavirus and its relationship with hormones and other metabolic parameters related. The study groups consist of 1

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Scopus (2)
Scopus Crossref
Publication Date
Thu Jun 01 2017
Journal Name
International Journal Of Science And Research
Precise Solutions of a Viscoelastic Fluid Flow in an Annular Pipe under an Impulsive Pressure with the Fractional Generalized Burgers' Model
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This paper deals with an analytical study of the flow of an incompressible generalized Burgers’ fluid (GBF) in an annular pipe. We discussed in this problem the flow induced by an impulsive pressure gradient and compare the results with flow due to a constant pressure gradient. Analytic solutions for velocity is earned by using discrete Laplace transform (DLT) of the sequential fractional derivatives (FD) and finite Hankel transform (FHT). The influences of different parameters are analyzed on a velocity distribution characteristics and a comparison between two cases is also presented, and discussed in details. Eventually, the figures are plotted to exhibit these effects.

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Publication Date
Tue Jan 01 2019
Journal Name
Plant Archives
Effect of the addition of guanidinoacetic acid to the dilute tris in some of the biochemical characteristics of the semen of the rams
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The study was planned to evaluate the effect of adding Guanidinoacetic acid in some characteristics of the sperm of the rams. This study was conducted in the animal field of the Animal Production Department / Faculty of Agricultural Engineering Sciences / University of Baghdad, for the period from 5/8/2018 to 28/2/2019. In this experiment, 3 rams were used at the age of 2-2.5 years and weighed 50-54 kg. The semen was collected early in the morning and once a week and the semen was pooled to remove the individual differences. The treatments were divided: GAA-free control group, treatment T1 (0.05 mg / 100 ml GAA), T2 treatment (0.1 mg / 100 ml GAA) and T3 treatment (0.2 mg / 100 ml GAA). The results of the study showed a significant decrease

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Scopus (1)
Scopus