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alkej-631
Free Convective Heat Transfer with Different Sections Lengths Placed at the Exit of a Vertical Circular Tube subjected to a Constant Heat Flux
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A free convective heat transfer from the inside surface of a uniformly heated vertical circular tube has been experimentally investigated under a constant wall heat flux boundary condition for laminar air flow in the ranges of RaL from 6.9108 to 5109. The effect of the different sections (restrictions) lengths placed at the exit of the heated tube on the surface temperature distribution, the local and average heat transfer coefficients were examined. The experimental apparatus consists of aluminum circular tube with 900 mm length and 30 mm inside diameter (L/D=30). The exit sections (restrictions) were included circular tubes having the same inside diameter as the heated tube but with different lengths of 600 mm (L/D=20), 900 mm (L/D=30), 1200 mm (L/D=40), 1500 mm (L/D=50), and 1800 mm (L/D=60). It was found that the surface temperature along the tube axial distance would be higher for restriction with length of 1800 mm (L/D=60) and it would be smaller for the restriction with length of 1200 mm (L/D=40). The results show that the local Nux and average Nusselt number were higher values for the restriction with length of 1200 mm (L/D=40) and smaller values for the restriction with length of 1800 mm (L/D=60). The results were correlated with empirical equations and presented as Logagainst Log for each case investigated and a general empirical equation was proposed for all cases.

 

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Publication Date
Fri Aug 20 2021
Journal Name
Iraqi Journal Of Laser
Design of Tunable Optical Band Pass Filter based on in-Line PM-Mach Zehnder Interferometer
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In this paper, tunable optical band-pass filters based on Polarization Maintaining Fiber –Mach Zehnder Interferometer presented. Tunability of the band-pass filter implemented by applying different mechanical forces N on the micro-cavities splicing regions (MCSRs). The micro-cavity formed by using three variable-lengths of single-mode polarization-maintaining fiber with (8, 16, 24) cm lengths, splice between two segments of (SMF-28) with (26, 13) cm lengths, using the fusion splicing technique.  Ellipsoidal shape micro-cavities experimentally achieved parallel to the propagation axis having dimensions between (12-24) μm of width and   (4-12) μm of length. A micro-cavity with width and length as high as 24 μm and 12 μ

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Publication Date
Sat Oct 01 2022
Journal Name
Baghdad Science Journal
Absorption and Fluorescence Properties of 3,6-bis(5-bromothiophen-2-yl)-2,5-bis(2-ethylhexyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione. A Covalent Fluorescence in Solution and in the Solid State
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In the cuurent article, the photophysical properties of 3,6-bis(5-bromothiophen-2-yl)-2,5-bis(2-ethylhexyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione were investigated. The visible absorption bands at 527, 558 and 362 nm in propylene carbonate and the compound was found to be fluorescent in solution and in the plastic film with emission wavelengths between 550- 750 nm. The Stokes Shift of P.C., acetonitrile, diethyl ether, Tetrahydrofuran THF, cyclohexane, dibutyl ether, and dichloromethane DCM  are 734, 836, 668, 601, 601, 719, and 804 cm-1 in respectively. The Stokes Shift Δ was less in THF and cyclohexane, than the solvents, which indicates that the energy loss is less between the excitation and fluorescence states. The

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Publication Date
Fri Oct 01 2010
Journal Name
Analytica Chimica Acta
A reversed phase high performance liquid chromatography method for the determination of fumonisins B1 and B2 in food and feed using monolithic column and positive confirmation by liquid chromatography/tandem mass spectrometry
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The development of a reversed phase high performance liquid chromatography fluorescence method for the determination of the mycotoxins fumonisin B1 and fumonisin B2 by using silica-based monolithic column is described. The samples were first extracted using acetonitrile:water (50:50, v/v) and purified by using a C18 solid phase extraction-based clean-up column. Then, pre-column derivatization for the analyte using ortho-phthaldialdehyde in the presence of 2-mercaptoethanol was carried out. The developed method involved optimization of mobile phase composition using methanol and phosphate buffer, injection volume, temperature and flow rate. The liquid chromatographic separation was performed using a reversed phase Chromolith® RP-18e column

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Publication Date
Wed Apr 30 2025
Journal Name
Journal Of Al-farabi For Humanity Sciences (jfhs)
Colonialism and Anticolonialism in English Fiction: A Study of Defoe’s Robinson Crusoe and H. G. Wells’ The Country of the Blind الاستعمار ومناهضته في الادب القصصي الإنجليزي: دراسة في رواية دانيل ديفو (روبنسون كروسو) وقصة هربرت جورج ويلز (بلد العميان)
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Colonialism as a movement was very popular in Europe more than two centuries before. It aimed at controlling and exploiting several countries in Africa and Asia in addition to imposing their power and control on uninhabited islands. It received adherence and criticism as well. There also appeared activists and nations who stood against it and its practices. English novels discussed this notion greatly by pointing out the bad practices of the colonizers and how the colonized received them. This paper explores two narrative fictions that tackle the different aspects of the term. While Defoe, in Robinson Crusoe (1719), shows a colonial European figure who expresses his superiority, Wells, in “The Country of the Blind” (1904), deconstructs

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Publication Date
Sat Jan 01 2022
Journal Name
Optik
Plasma parameters of Au nano-particles ablated on porous silicon produced via Nd-YAG laser at 355 nm for sensing NH3 gas
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a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the rod that appears for Au NPs, in addition to that, TEM has been an indication of the fact that syn

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Publication Date
Sun Nov 23 2025
Journal Name
Yarsi Medical And Dental Science - Yasmine Journal
Oral Biopsy: Evaluating Awareness and Knowledge Among Dental Students at University of Baghdad: Oral Biopsy: Evaluating Awareness and Knowledge Among Dental Students
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Introduction Oral biopsy is a fundamental diagnostic procedure in dentistry, essential for the early detection of oral cancer and other pathologies. While theoretical knowledge is a core component of dental education, the translation of this knowledge into clinical confidence and practical ability is critical for patient care. Objective: : evaluate the awareness, knowledge, and self-perceived ability to perform oral biopsies Material and Methods: A cross-sectional study was conducted among dental students. Participants (n=110) comprising 14 multiple-choice questions assessing key variables: knowledge of biopsy principles, techniques, lesion identification, specimen preservation, and ability to perform the procedure Results: While theoretica

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Publication Date
Thu Nov 04 2021
Journal Name
Optik - International Journal For Light And Electron Optics
Plasma parameters of Au nano-particles ablated on porous silicon produced via Nd-YAG laser at 355 nm for sensing NH3 gas
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The current study aimed the syntheses and characterizations of Gold nanoparticles (Au NPs) using a laser ablation Q-switched Nd: YAG laser with a wave-length of 355 nm at a variety of laser pulse energies (E) and deposited on porous silicon (PS). Optical emission spectrometer was used to diagnosed medium air to study gold plasma characteristics and prepared Au nanoparticles. The laser pulse energy influence has been studied on the plasma characteristics in air. The data showed the emergence of the ionic (Au II) spectral emission lines in the gold plasma emission spectrum. XRD has been utilized to examine structural characteristics. Moreover, AFM results 37.2 nm as the mean value of the diameter that is coordinated in a shape similar to the

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Publication Date
Sun Sep 27 2020
Journal Name
Iraqi National Journal Of Nursing Specialties
Effectiveness of an Education Program on Nursing Staffs' Knowledge about Infection Control Measures at Intensive Care Unit in Al-Diwaniya Teaching Hospital
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Objectives: To determine the effectiveness of the educational program on nursing staff knowledge about infection control measures at the Intensive Care Unit in Al-Diwaniya Teaching Hospital.

Methodology: A pre-experimental design (one group design: pre-test and post-test) was used. This study was conducted in Al-Diwaniya Teaching Hospital for the period from ( 20th February to 5th March, 2020) on a non-probability (purposive) sample consisting of (25 nurses) working in ICU. A questionnaire was built as a data collection tool and consisted of two parts:

First part: The demographic characteristics of the nursing staff (age, gender, level of education, years of experien

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Publication Date
Fri Dec 01 2023
Journal Name
Physical Chemistry Research
Thermophysical Study of Ethylene Glycol + H<inf>2</inf>O and Ethylene Glycol + (DMF/H<inf>2</inf>O) at 298.15 K
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n this research, some thermophysical properties of ethylene glycol with water (H2O) and two solvent mixtures dimethylformamide/ water (DMF + H2O) were studied. The densities (ρ) and viscosities (η) of ethylene glycol in water and a mixed solvent dimethylformamide (DMF + H2O) were determined at 298.15 K, t and a range of concentrations from 0.1 to1.0 molar. The ρ and η values were subsequently used to calculate the thermodynamics of mixing including the apparent molar volume (ϕv), partial molar volume (ϕvo) at infinite dilution. The solute-solute interaction is presented by Sv results from the equation ∅_v=ϕ_v^o+S_v √m. The values of viscosity (B) coefficients and Falkenhagen coefficient(A) of the Jone-Dole equation and Gibbs free

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Scopus
Publication Date
Tue Feb 05 2019
Journal Name
Journal Of The College Of Education For Women
Health awareness and health culture among a sample of mothers aged (20 – 43 year) lived in urban and rural zones in Baghdad
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The study aimed to identify the level of health awareness and health education among mothers zones, urban and rural areas as well as to identify the differences between them and to achieve this study was conducted on a sample of (121) or been Akhittarhn randomly, aged (20 - 43 years) and applied them to a questionnaire to measure the health awareness, which formed from a group of paragraphs, and after the collection of data was treated using the statistical software (SAS), where research showed many of the results are:
1/ Reached the age group ranging between (20-30 years), the highest rate for the present, where was (40.51%), while in the countryside matched by age group (31-40 years old) in terms of (54.76%)./ It turns out that the

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