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Study Effect of Central Rectangular Perforation on the Natural Convection Heat Transfer in an Inclined Heated Flat Plate
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Anumerical solutions is presented to investigate the effect of inclination angle (θ) , perforation ratio (m) and wall temperature of the plate (Tw) on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole). The flat plate with dimensions of (128 mm) length × (64 mm) width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5). The values of angle of inclination were (0o, 15o 30o 45o 60o) from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100oC). To investigate the temperature, boundary layer thickness and heat flux distributions; the numerical computation is carried out using a very efficient integral method to solve the governing equation. The results show increase in the temperature gradient with increase in the angle of inclination and the high gradient and high heat transfer coefficients located in the external edges of the plate, for both cases: with and without holed plate. There are two separation regions of heat transfer in the external edge and the internal edges. The boundary layer thickness is small in the external edge and high in the center of the plate and it decreases as the inclination angle of plate increases. Theoretical results are compared with previous result and it is found that the Nusslet numbers in the present study are higher by (22 %) than that in the previous studies. And the results show good agreement in range of Raleigh number from 105 to 106.

 

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Publication Date
Mon Jul 01 2019
Journal Name
Plant Archives
Effect of melatonin administration with different light colors on the production of local chickens
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This study aims to observe the effect of melatonin implantation and exposure to different light colors and their interaction on productive in local Iraqi chicken. This study was conducted at the poultry farm of the Department of Animal Production/College of Agriculture/University of Baghdad/Abu Ghraib, on 252 birds (180 females and 72 males). The birds were divided into three sections (white, red and green) each section contains two lines, one of which has been planted melatonin under the skin of the neck of birds and the other has not been planted hormone. The results of the study showed significant improvement in productive traits such as egg proportion rate, egg weight, cumulative eggs number, egg mass and feed conversion rate. That the

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Scopus
Publication Date
Thu Apr 05 2012
Journal Name
مجلة القادسية للعلوم
Effect of some environmental factors on the tolerance of Bacillus subtilis to heavy metals
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Abstract Twelve isolates of bacteria were obtained from samples of different soils and water amended with 100µg/ml of five heavy metals chlorides (i.e: Aluminum Al+2, Iron Fe+2, Lead Pb+2, Mercury Hg+2 and Zinc Zn+2). Four isolates were identified as Bacillus subtilis and B. subtilis (B2) isolate was selected for this study according to their resistance to all five heavy metals chlorides. The ability of B. subtilis (B2) isolate for growing in different concentration of heavy metals chlorides ranging from 200-1200 µg/ml was tested. The highest conc. that B. subtilis (B2) isolate tolerate was 1000 µg/ml for Al+2, Fe+2, Pb+2, and Zn+2and 300 µg/ml for Hg+2 for 24hour. The effect of heavy metals chlorides on bacterial growth for 72 hrs was

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Publication Date
Sat Jan 01 2022
Journal Name
Proceedings Of 2nd International Multi-disciplinary Conference Theme: Integrated Sciences And Technologies, Imdc-ist 2021, 7-9 September 2021, Sakarya, Turkey
Investigation of the Effect of Diabetes on Lower Limb Muscles with Surface Electromyography (EMG)
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Publication Date
Sat Aug 01 2020
Journal Name
Key Engineering Materials
Irradiation Duration Effect of Gamma Ray on the Compressive Strength of Reactive Powder Concrete
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Reactive Powder Concrete (RPC) could be considered as the furthermost significant modern high compressive strength concrete. In this study, an experimental investigation on the impact of micro steel fiber volume fraction ratio and gamma ray irradiation duration influence upon the compressive strength of RPC is presented. Three volume fraction ratios (0.0, 1.0 and 1.5) % was implemented. For each percentage of the adopted fiber ratios, six different irradiation duration was considered; these are (1, 2, 3, 4, 5 and 6) days. Gamma source (Cs-137) of energy (0.662) MeV and activity (6) mci was used. In a case of zero volume fraction ratio, the experimental results showed that gamma ray had a significant influence on the reducing of the

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Crossref
Publication Date
Sat Jan 01 2011
Journal Name
Iraqi Journal Of Physics
The Effect of CdCl2 and annealing treatments on structural properties of CdS/CdTe heterojunction
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CdS and CdTe thin films were thermally deposited onto glass substrate. The CdCl2 layer was deposited onto CdS surface. These followed by annealing for different duration times to modify the surface and interface of the junction. The diffraction patterns showed that the intensity of the peaks increased with the CdCl2/annealed treatment, and the grain sizes are increased after CdCl2/annealed treatment

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Publication Date
Mon May 22 2023
Journal Name
Proceedings Of The 1st International Conference On Frontier Of Digital Technology Towards A Sustainable Society
Effect of thermal annealing on the structural and optical properties of Sb2Se3 thin films
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In this paper the effect of thermal annealing on the structural and optical properties of Antimony Selenide (Sb2Se3) is investigated. Sb2Se3 powder is evaporated on clean amorphous glass substrates at room temperature under high vacuum pressure (4.5×10-6 mbar) to form thin films. The structural investigation was done with the aid of X-ray diffraction (XRD) and atomic force microscopy (AFM). The amorphous to polycrystalline transformation of these thin films was shown by X-ray diffraction analysis after thermal annealing. These films' morphology is explained. (UV-Vis ) spectra in ranges from 300 to 1100 nm was used to examine the optical properties of the films .The absorption coefficient and optical energy gap of the investigated films are

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Scopus Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Key Engineering Materials
Irradiation Duration Effect of Gamma Ray on the Compressive Strength of Reactive Powder Concrete
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Reactive Powder Concrete (RPC) could be considered as the furthermost significant modern high compressive strength concrete. In this study, an experimental investigation on the impact of micro steel fiber volume fraction ratio and gamma ray irradiation duration influence upon the compressive strength of RPC is presented. Three volume fraction ratios (0.0, 1.0 and 1.5) % was implemented. For each percentage of the adopted fiber ratios, six different irradiation duration was considered; these are (1, 2, 3, 4, 5 and 6) days. Gamma source (Cs-137) of energy (0.662) MeV and activity (6) mci was used. In a case of zero volume fraction ratio, the experimental results showed that gamma ray had a significant influence on the reducing of the

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Crossref (2)
Scopus Crossref
Publication Date
Thu Jun 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Different Light Cure Systems on Microhardness of Bulk Fill Composite Materials
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Background: The aim of this study was to evaluate the effect of three types of light curing devices QTH, LED and Flashmax on the surface microhardness of three types of bulkfill composite resins; Filtek Bulkfill posterior composite ( 3M), Tetric Evo Ceram ( Ivoclar Vivadent) and Sonicfill composite ( Kerr) Materials and methods: Total number of 90 samples was prepared, 30 samples for each type of bulkfill composite, were divided into three main groups, group A: Filtek posterior bulkfil (3M), group B: Tetric Evo Ceram (Ivoclar Vivadent) and group C: contain Sonicfill composite (kerr). Which then divided into three subgroups (n= 10) (1) Samples cured by QTH system (2) Samples cured by LED system and (3) samples cured by Flashmax system the

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Crossref
Publication Date
Tue Mar 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
The effect of gender diversity of board directors and accounting conservatism on firm value
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The study aims to investigate the relationship between the gender diversity of board director, the accounting conservatism and firm value in Iraqi firms. The sample was represented by 30 Iraqi firms listed on the Iraqi market over the period 2017. The research was based on the main hypothesis that gender diversity has a positive relationship with conservatism and firm value, that conservatism as an intermediate variable will enhance the positive relationship between gender diversity and firm value. The study reached results that support the research hypotheses. The appointment of females to the board helps improve the provision of conservative accounting information and avoids overstate when reporting earnings. Based on these res

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Crossref (2)
Crossref
Publication Date
Wed Oct 28 2020
Journal Name
International Journal Of Agricultural And Statistical Sciences 16
Effect of nano-fertilizers and amino acids on the growth and yield of broccoli
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