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joe-2040
Numerical Simulation of 3D- Flow Structure and Heat Transfer for Longitudinal Riblet Upstream of Leading Edge Endwall Junction of Nozzle Guide Vane
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The simulation have been made for  3D flow structure and heat  transfer with and without

longitudinal riblet upstream of leading edge vane endwall junction of first stage nozzle guide vane .The research explores concept of weakening the secondary flows and reducing their harmful effects.Numerical investigation involved examination of the secondary flows ,velocity and heat transfer rates by solving the governing equations (continuity, Navier -stokes and energy equations ) using the known package FLUENT version (12.1).The governing equations were solved for three dimentional, turbulent flowe, incompressible with an appropriate turbulent model (k-ω,SST) .The numerical solution was carried out for 25 models of V-groove riblet with wide ranges of height (h) and space (s). The results indicated that, the riblet endwall junction was a powerful tool for controlling the flow structure, reducing secondary flow formation,and elimination the effect of heat transfer at leading edg and passage . The drag reduction produced by riblet was proportional with their height and space. V-groove riblet with dimension of (h=1.35mm and s=2.26mm) was found to be the most effective in reduction of drag (2.7%) and heat transfer (21%) so it was selected as an optimum dimension of riblet model. The results also showed that the drag reduction produced by riblet was proportional to their size. The riblet model had a great effect in elimination spanwise ,pitchwise velocities ,but strength the streamwise velocity .At leading edge ,the effect of secondary flow was extended up to 23% from span height and 35% upstream leading edge .The riblet model caused an increase in momentom at a region very close to leading edge and to move stagnation point very close to the leading edge.

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The Enneagram Personality Types (The feeling center) and Academic Self Among the distinguished Students
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The current study aims to

1) identify the prevalent Enneagram personality types and the academic self among the sixth-grade students of the distinguished secondary schools; 2) the differences of relationship between the Enneagram personality types and the academic self-concept based on gender; 3) identify the correlation between the Enneagram personality types and the academic self-concept; and 4) identify the contribution of each type of personality types to the academic self-concept. To this end, two instrument were used to collect the data: Riso-Hudson’s scale,1995 was administered to measure enneagram types which had translated to the Arabic language by ( al-yassery,2004), the other instrument was

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Publication Date
Mon Feb 14 2022
Journal Name
Journal Of Educational And Psychological Researches
Cognitive Beliefs and Their Relationship to Self-Organized Learning Strategies at the Preparatory Stage
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The study aims to identify the level of cognitive beliefs, as well as to identify the level of self-organized learning strategies among intermediate school students. The study also aims to identify the differences in the level of self-organized learning strategies among intermediate school students in term of gender, branch (scientific, literary). In order to achieve the research objectives, the researcher designed a scale to measure the cognitive beliefs. As for the scale of self-organized learning strategies, the researcher adopted a scale of (Pintrich et al. 1991), which was translated by (Izzat Abdelhamid, 1999) , For self-organized learning strategies, the sample consisted of (400) students from the research population, whic

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Publication Date
Thu Aug 24 2023
Journal Name
Migration Letters
Imaginative Interconnection and its Relationship to Spatial Thinking Among Preparatory School Students in Mathematics
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Scopus
Publication Date
Wed Sep 30 2015
Journal Name
College Of Islamic Sciences
The other day in the Holy Quran and the four Gospels: A comparative study
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The other day in the Holy Quran and the four Gospels

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Publication Date
Wed Mar 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
Salivary protein carbonyl and selected antioxidants in relation to dental caries among pregnant women
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Background: Pregnancy is a physiological condition that affects the general and oral health.It is also associated with an increase in oxidative stress, which may presispose to oral diseases including dental caries. Aim of the study: This study aimed to measure salivary protein carbonyl, glutathione peroxidase and selenium levels of women who are pregnant and their association with dental caries in comparison to non-pregnant women, and to find out the mostly affected biomarker of oxidative stress during pregnancy. Subjects, materials and methods: A cross-sectional research was performed for a samples of 30 pregnant and 30 non-pregnant women who were chosen from city of Baghdad's Primary Healthcare Centers. Both groups aged 25-30 years. In

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Publication Date
Wed Oct 07 2026
Journal Name
Al–bahith Al–a'alami
Iraqi Satellite Music Channels and Their Role in Spreading Negative Values among University Youth
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This study aims to clarify the role of Iraqi satellite channels in spreading negative values ​​among university youth; and the tendency of this segment to simulate the descending behaviors and pseudo-peculiar concepts of our society, which are displayed through the screens of these channels, based on the relevant media literature such as scientific references and the results of previous studies and research.

The study followed the survey methodology to examine the public based on the questionnaire as a research tool, which was distributed to a sample of male and female students of Baghdad University enrolled in the university for the academic year 2011-2012.

In order to achieve the specific objectives of this research

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Publication Date
Fri Jun 01 2018
Journal Name
Nano Hybrids And Composites
OLED Hybrid Light Emitting Devices with ZnS QDs, TPBi and Alq3 Electron Transport Layers
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Semiconductor quantum dots (QDs) have attracted tremendous attentions for their unique characteristics for solid-state lighting and thin-film display applications. A simple chemical method was used to synthesis quantum dots (QDs) of zinc sulfide (ZnS) with low cost. The XRD) shows cubic phase of the prepared ZnS with an average particles size of (3-29) nm. In UV-Vis. spectra observed a large blue shift over 38 nm. The band gaps energy (Eg) was 3.8 eV and 3.37eV from the absorption and photoluminescence (PL) respectively which larger than the Eg for bulk. QDs-LED hybrid devices were fabricated using ITO/ PEDOT: PSS/ Poly-TPD/ ZnS-QDs/ with different electron transport layers and cathode of LiF/Al layers. The EL spectrum reveals a bro

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Publication Date
Fri Aug 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Comparison between the Local Polynomial Kernel and Penalized Spline to Estimating Varying Coefficient Model
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Analysis the economic and financial phenomena and other requires to build the appropriate model, which represents the causal relations between factors. The operation building of the model depends on Imaging conditions and factors surrounding an in mathematical formula and the Researchers target to build that formula appropriately. Classical linear regression models are an important statistical tool, but used in a limited way, where is assumed that the relationship between the variables illustrations and response variables identifiable. To expand the representation of relationships between variables that represent the phenomenon under discussion we used Varying Coefficient Models

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Publication Date
Sun Sep 02 2012
Journal Name
Baghdad Science Journal
Benzoic acid concentration levels recovery in Ketchup and Sauce products available in local market.
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This research is dealing with five sample of tomato ketchup products available in local market that were respectively as follows: Hello-Baghdad Iraq, Tiffany-Abu Dhabi, Melody-Dubai, Baidar-Saudi Arabia, and Altunsa-Turkey. Also it is dealing with four sample of sauce products available in local market that were respectively as follows: Hello-Baghdad, Iraq, Al-Badawi-Baghdad Iraq, Family-Baghdad, Iraq, and Hala-Amman Jordon. Analysis was performed on each sample three times and mean of the reading was taking. Samples were tested through terse and shorthand from lengthened steps. The spectrophotometric method used rely on theoretical and practical bases in extraction and diagnosis by UV spectrophotometer. This method in short notes, consiste

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Publication Date
Thu Dec 31 2020
Journal Name
International Journal On Governmental Financial Management
The Shift towards the Results-Oriented Budget and Its Impact on Government Performance Information
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