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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
Tue Mar 01 2016
Journal Name
Al-academy
Semantic Analogy of Quran Text Content Found in Ornamental Figures in Islamic Architecture: وسام كامل عبد الامير
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This study aims at creating an analogy between Quran text Contents as meanings that have representations as visional shapes within ornamental figures in Islamic architecture. The theoretical framework of the study deals with the concept of semantics and its parts, artistic contents of Quran texts, and ornamental figures in Islamic architecture. The study procedures included a population of (69) figures, (5) of them were chosen deliberately for analysis in accordance with a form that had been presented to a number of experts to ensure its validity. The study reached a number of conclusions, the most significant among them are: adopting natural denotation of direct reference in order to link the ornamental figure to the source it was taken

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Publication Date
Fri Jan 24 2020
Journal Name
Petroleum And Coal
Evaluation of Geomechanical Properties for Tight Reservoir Using Uniaxial Compressive Test, Ultrasonic Test, and Well Logs Data
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Tight reservoirs have attracted the interest of the oil industry in recent years according to its significant impact on the global oil product. Several challenges are present when producing from these reservoirs due to its low to extra low permeability and very narrow pore throat radius. Development strategy selection for these reservoirs such as horizontal well placement, hydraulic fracture design, well completion, and smart production program, wellbore stability all need accurate characterizations of geomechanical parameters for these reservoirs. Geomechanical properties, including uniaxial compressive strength (UCS), static Young’s modulus (Es), and Poisson’s ratio (υs), were measured experimentally using both static and dynamic met

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Publication Date
Tue Jan 09 2018
Journal Name
Research Journal Of Pharmacy And Technology
Sequencing of Mitochondrial COI gene in new Iraqi record Paropeas achatinaceum L. P. Feiffer, 1846, Gastropoda: Subulinidea
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Fifty snails of Paropeas achatinaceum specimens were collected and classified from four areas in Baghdad-Iraq from the period between June and July, 2017. The snails were divided into two groups (each group contain 25 snails). Two environment conditions were used in this study. Natural environment considered as control and experimental environment contains Citrus sinensis (L.) roots as snail’s source food. The comparison result between snail weights in the nature and experimental environment was not significant (0.497, 95% confidence interval [CI] 0.01209–0.02309). Also, the comparison between snail weights in the nature environment and the food mean weight was significant (0.014, 95% confidence interval [CI] 0.00591-0.04109), while the

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Publication Date
Fri Nov 30 2018
Journal Name
Oriental Journal Of Chemistry
Viscosity and Density Studies of Drugs in Aqueous Solution and in Aqueous Threonine Solution at 298.15 K
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Viscosities (η) and densities (ρ) of atenolol and propranolol hydrochloride in water and in concentrations (0.05 M) and (0.1 M) aqueous solution of threonine have been used to reform different important thermodynamic parameters like apparent molal volumes fv partial molal volumes at infinite dilution fvo , transfer volume fvo (tr), the slop Sv , Gibbs free energy of activation for viscous flow of solution ΔG*1,2 and the B-coefficient have been calculated using Jones-Dole equation. These thermodynamic parameters have been predicted in terms of solute-solute and solute-solvent interaction.

Publication Date
Wed Mar 01 2023
Journal Name
Journal Of Photochemistry And Photobiology A: Chemistry
Improved photocatalytic degradation of methyl violet dye and pathogenic bacteria using g-C3N4 supported phosphotungstic acid heterojunction
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Publication Date
Fri Sep 15 2023
Journal Name
Journal Of Water Resources And Geosciences
Evaluation of Water and Wheat Productivity under Center Pivot Sprinkler Irrigation in Desert Soils/Holly Karbala Governorate
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Two field experimسents were conducted in one of the fields of the Agriculture Division of Ain Al-Tamr /Holy Karbala Governorate at two sites of different textures during the agricultural season 2020/2021. The first site has sandy loam texture (gypsum soils). The second site has loamy sand texture (calcareous soils). The factors of the study included: The first factor included two types of soil, gypsum and calcareous soil. The second factor is the tillage systems (no-tillage, spring spike harrows, disc harrows, and mold board plow). The experiment was designed in the two study sites according to the RCBD with three replications. The Valley type center pivot irrigation system was evaluated before planting, three speeds, 30, 50 and 100% of th

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Publication Date
Thu Jan 01 2009
Journal Name
Ibn Al- Haitham J. Fo R Pure & Appl. Sci
Multiple Mixing Ratios of Gamma Rays Erγ)nEr(n, From 168 168 Reaction  Using a2 – Ratio Method
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The -mixing of  - transition in Er 168 populated in Er)n,n(Er 168168  reaction is calculated in the present work by using a2- ratio method. This method has used in previou studies [4, 5, 6, 7] in case that the second transition is pure or for that transition which can be considered as pure only, but in one work we applied this method for two cases, in the first one for pure transition and in the 2nd one for non pure transitions. We take into accunt the experimental a2- coefficient for p revious works and -values for one transition only [1]. The results obtained are, in general, in agood agreement within associated errors, with those reported previously [1], the discrepancies that occur are due to inaccuracies existing

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Publication Date
Fri May 01 2020
Journal Name
Plant Archives
Correlation study of retinol binding protein(-4), nesfatin and thyroid hormones in colorectal cancer Iraqi Male patients
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The third most ordinarily cancer type diagnosed in male and is Colorectal cancer (CRC) and it is widely spread in developed countries. Most of CRC arises from development of adenomatous polyps. The current study aimed to determine whether serum retinol binding protein 4 (RBP4) and Nesfatin-1 can be used as a novel biomarker for diagnosis of CRC. Nesfatin-1, RBP4 and Thyroid Hormones (T3, T4 and TSH) levels were measured in fifty sera of male patients suffering from CRC before chemotherapy initiation treatment as G1, G2 after first chemotherapy cycle dose and G3 after second chemotherapy cycle dose compared with twenty five male volunteers as a control G4. The results showed a significant increased in RBP 4 concentration in G3 and a signific

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Publication Date
Fri Apr 16 2021
Journal Name
Turkish Journal Of Computer And Mathematics Education
Effective reading skills and their relationship to deep understanding of chemistry among middle school students in Iraq
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Publication Date
Tue Jun 21 2022
Journal Name
Peerj Computer Science
Performance evaluation of frequency division duplex (FDD) massive multiple input multiple output (MIMO) under different correlation models
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Massive multiple-input multiple-output (massive-MIMO) is considered as the key technology to meet the huge demands of data rates in the future wireless communications networks. However, for massive-MIMO systems to realize their maximum potential gain, sufficiently accurate downlink (DL) channel state information (CSI) with low overhead to meet the short coherence time (CT) is required. Therefore, this article aims to overcome the technical challenge of DL CSI estimation in a frequency-division-duplex (FDD) massive-MIMO with short CT considering five different physical correlation models. To this end, the statistical structure of the massive-MIMO channel, which is captured by the physical correlation is exploited to find sufficiently

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