Preferred Language
Articles
/
GBedRo4BVTCNdQwCiEB8
Experimental study of natural convection heat transfer on an enclosure partially filled porous medium heated from below by constant heat flux
...Show More Authors

This study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperature from testing rig are used to extract the temperature distribution, local Nusselt number and average Nusselt number. Moreover, a comparison between the numerical result of the same problem published recently and present experimental results has been executed and discussed. It is evinced that; the heat transfer and fluid flow are affected by thickness of porous layer and be maximum at porous layer thickness (0.25L) with larger heater length(20cm) and heat flux (q= 600 Watt/m2) which is approximately (180%) for the average Nu when compared with (Hp=0.75L). Also, the effect of the increasing in heater length (δ) on the averaged heat transfer enhancement is more pronounced for large heater size and 25% of average enhancement is achieved for (δ=20cm) compared to (δ=7cm). However, the greater temperature distribution is found at Hp=2.5cm and 5cm at bottom and first quarter of the cavity (heater surface height Y=0 cm and Y=5 cm) respectively and minimum temperature at top (insulation wall Y=20 cm). Nearly, same shape for heat transfer for different case with clearly difference at small heater (δ=7cm).

Scopus Crossref
View Publication
Publication Date
Sat Oct 01 2011
Journal Name
Iraqi Journal Of Physics
The Role of Annealing Temperature on the Optical Properties of Thermally Deposited CdTe Films
...Show More Authors

A polycrystalline CdTe film has been prepared by thermal evaporation technique on glass substrate at substrate temperature 423 K with 1.0 m thicknesses. The film was heated at various annealing temperature under vacuum (Ta =473, 523 and K). Some of physical properties of prepared films such as structural and optical properties were investigated. The patterns of X-ray diffraction analysis showed that the structure of CdTe powder and all films were polycrystalline and consist of a mixture of cubic and hexagonal phases and preferred orientation at (111) direction.
The optical measurements showed that un annealed and annealed CdTe films had direct energy gap (Eg). The Eg increased with increasing Ta. The refractive index and the real p

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Journal Of The Mechanical Behavior Of Materials
The effect of using polyolefin fiber on some properties of slurry-infiltrated fibrous concrete
...Show More Authors
Abstract<p>Slurry-infiltrated fibrous concrete (SIFCON) is a special type of concrete that has great strength, as well as high ductility. However, the unit weight is high, which exceeds the unit weight of fiber-reinforced concrete, because of the high fiber content. This research aims to verify the compressive and flexural strength, as well as the density of SIFCON when using two different fibers (steel and polyolefin). Sometimes mono type of fiber steel or polyolefin, sometimes by hybridizing two types of fiber steel + polyplefin. Volume fraction (6% for all species) was used. Hook-end steel fiber and polyolefin fiber are used. With hybridization, a total volume fraction of 6% was used, which </p> ... Show More
View Publication
Crossref (2)
Crossref
Publication Date
Sat Jul 23 2022
Journal Name
Environmental Monitoring And Assessment
Impact of using magnetic water on the micro structure of leached saline-sodic soil
...Show More Authors

View Publication
Scopus (4)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Jun 27 2020
Journal Name
Iraqi Journal Of Science
On Analytical Solution of Time-Fractional Type Model of the Fisher’s Equation
...Show More Authors

In this paper, the time-fractional Fisher’s equation (TFFE) is considered to exam the analytical solution using the Laplace q-Homotopy analysis method (Lq-HAM)”. The Lq-HAM is a combined form of q-homotopy analysis method (q-HAM) and Laplace transform. The aim of utilizing the Laplace transform is to outdo the shortage that is mainly caused by unfulfilled conditions in the other analytical methods. The results show that the analytical solution converges very rapidly to the exact solution.

View Publication Preview PDF
Scopus (4)
Crossref (1)
Scopus Crossref
Publication Date
Wed Dec 12 2018
Journal Name
Iop Conference Series Materials Science And Engineering
Effect of Rejuvenating Agent on the Mixtures Containing High Percent of Reclaimed Asphalt Pavement
...Show More Authors

Due to economic reasons or need for environmental conservatism or also preserve the natural resources; there has been an increasing shift towards the use of reclaimed asphalt pavement (RAP) materials in the pavement construction industry. Therefore, use the Reclaimed Asphalt Pavement (RAP) has been enormously increased in pavement construction and has been become common practice in many countries. Nevertheless, this is a relatively new concept in Iraq, and has to be remarked that is not used RAP in the production of HMA and this valuable material is mostly degraded. For this purpose, the reclaimed materials were collected from deteriorated pavement segments. The components of asphalt mixtures consist of: two asphalt penetration grades (40-5

... Show More
Scopus (2)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Fri Nov 15 2024
Journal Name
Iraqi Journal Of Science
The Impact of Partial Solar Eclipse on the Observation of Neutral Hydrogen Emission Line
...Show More Authors

The research involves examining the influence of partial solar eclipse on the strength of neutral hydrogen from the Sun. Baghdad University Radio Telescope (BURT) was used to monitor the partial solar eclipse on the 25th of October, 2022. Radio observations from the Sun were recorded from 11:30 AM to 03:36 PM. This means that the HI emission from the Sun was recorded before, during and after the event. It was noticed, that at the moment of maximum eclipse, ~ 46% of the Sun’s disk was covered by the Moon. For the purpose of this research, the solar radio wave intensity was monitored and the solar flux density was determined at different times, i.e. before, during and after the partial solar eclipse. The obtained results showed that

... Show More
View Publication
Scopus Crossref
Publication Date
Thu Mar 25 2021
Journal Name
Engineering And Technology Journal
The Effect of the Number of Key-Frames on the Facial Emotion Recognition Accuracy
...Show More Authors

Key-frame selection plays an important role in facial expression recognition systems. It helps in selecting the most representative frames that capture the different poses of the face. The effect of the number of selected keyframes has been studied in this paper to find its impact on the final accuracy of the emotion recognition system. Dynamic and static information is employed to select the most effective key-frames of the facial video with a short response time. Firstly, the absolute difference between the successive frames is used to reduce the number of frames and select the candidate ones which then contribute to the clustering process. The static-based information of the reduced sets of frames is then given to the fuzzy C-Means algor

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sat May 01 2021
Journal Name
Journal Of Physics: Conference Series
The influence of temperature and size on the absorption coefficient of CdSe quantum dots
...Show More Authors
Abstract<p>Because of Cadmium selenide quantum dots (CdSe quantum dots) has a tuning energy gap in the visible light range, therefore; it is provided a simple theoretical model for the absorption coefficient of CdSe quantum dots, where the absorption coefficient determines the extent to which the light of a material can penetrate a specific wavelength before it is absorbed. CdSe quantum dots have an energy gap can be controlled through two effects: the temperature and the dot size of them. It is found that; there is an absorption threshold for each directed wavelength, where CdSe quantum dots begin to absorb the visible spectrum at a size of 1.4 nm at room temperature for a directed wavelength 3</p> ... Show More
View Publication
Crossref (2)
Crossref
Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Assessment of Genotoxicity of Citrobacter freundii Bacteriocin on Bone Marrow Cells in Albino Mice
...Show More Authors

Genotoxic effects of crude bacteriocin extracted from Citrobacter freundii were detected on albino mice bone marrow cells in vivo, using micronucleus (MN) and comet assay. The mice were administered intraperitoneally with 37.5, 75, 150 and 300 mg/kg of the extract for 24 hours. C. freundii was isolated from patients suffering from urinary tract infections (UTI). The bacteriocin producing isolates were determined using cup assayand the most efficient bacteriocin producers were selected. Bacteriocin was extracted from the efficient isolates via the induction with Mitomycin-C (2 mg/ml). Bacteriocin activity (320 U/ml) was determined by well diffusion method, while the protein concentration (2900µg/ml) was estim

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Wed Apr 19 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Al2O3 Additives on Some Mechanical Properties of Un Saturated Polyester Resin
...Show More Authors

   This study included preparation for the unsaturated polyester samples before and after reinforced by the Alumina oxide powder of different volume fraction amounting (2%,4%,6%).    And this research included the study of some of mechanical properties such as (Hardness,compressive,wear).     The results showed that the increase of the hardness and compressive strength after the reinforced and the increase with the volume fraction increase.   As the wear test shows that the wear rate increases with applied load increase(5,10,15) from  (10.6-18.6) gm/cm befor reninforced and from(5.4-15.2)gm/cm,(4.7-12.9)gm/cm,(48.1)gm/cm,after reinforced from the different volume fraction, and t

... Show More
View Publication Preview PDF