Preferred Language
Articles
/
alkej-181
Thermo-Rheological Investigation and Modeling of the Shear Viscosity of Polypropylene above the Melting Temperature
...Show More Authors

The increasing use of polymeric materials in the daily life, leads to challenges in the processing industry to deliver high performance materials with affordable terms. However, new processing techniques lead to high costs. In order to reduce processing costs it is necessary to understand the non-Newtonian behavior of the polymers in their molten state to be able to simulate the processes before the construction of the plants starts. Here the shear thinning behavior of the viscosity of polymeric melts is essential. Thus, this paper deals with the experimental investigation of the thermo-rheological behavior of the viscosity of one of the most used polymers (Polypropylene) over a wide range of temperatures and shear rates.  Furthermore, a modeling approach of the viscosity via a generalized non-Newtonian law combined with an Arrhenius model is done.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Apr 01 2023
Journal Name
Journal Of Engineering
Investigation of Groundwater and The Impact of Over-Pumping in Al-Haydariyah Region, Iraq
...Show More Authors

In this study; a three-dimensional model was created to simulate groundwater in Al-Haydariyah area of the governorate of Al-Najaf. A solid model was created to utilize the cross sections of 25 boreholes in the research region, and it was made out of two layers: sand and clay. The steady-state calibration was employed in six observation wells to calibrate the model and establish the hydraulic conductivity, which was 17.49 m/d for sand and 1.042 m/d for clay, with a recharge rate of 0.00007 m/day. The wells in the research region were reallocated with a distance of 1500 m between each well, resulting in 140 wells evenly distributed throughout the study area and with a discharge of 5 l/s, and the scenarios were run for 1000

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Aug 10 2022
Journal Name
Mathematics
Modeling and Analysis of the Influence of Fear on the Harvested Modified Leslie–Gower Model Involving Nonlinear Prey Refuge
...Show More Authors

Understanding the effects of fear, quadratic fixed effort harvesting, and predator-dependent refuge are essential topics in ecology. Accordingly, a modified Leslie–Gower prey–predator model incorporating these biological factors is mathematically modeled using the Beddington–DeAngelis type of functional response to describe the predation processes. The model’s qualitative features are investigated, including local equilibria stability, permanence, and global stability. Bifurcation analysis is carried out on the temporal model to identify local bifurcations such as transcritical, saddle-node, and Hopf bifurcation. A comprehensive numerical inquiry is carried out using MATLAB to verify the obtained theoretical findings and und

... Show More
View Publication
Scopus (20)
Crossref (8)
Scopus Clarivate Crossref
Publication Date
Mon Jun 30 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Viscosity Reduction of Sharqi Baghdad Heavy Crude Oil Using Different Polar Hydrocarbons, Oxygenated Solvents
...Show More Authors

This work studied the facilitation of the transportation of Sharqi Baghdad heavy crude oil characterized with high viscosity 51.6 cSt at 40 °C, low API 18.8, and high asphaltenes content 7.1 wt.%, by reducing its viscosity from break down asphaltene agglomerates using different types of hydrocarbon and oxygenated polar solvents such as toluene, methanol, mix xylenes, and reformate. The best results are obtained by using methanol because it owns a high efficiency to reduce viscosity of crude oil to 21.1 cSt at 40 °C. Toluene, xylenes and reformate decreased viscosity to 25.3, 27.5 and 28,4 cSt at 40 °C, respectively. Asphaltenes content decreased to 4.2 wt. % by using toluene at 110 °C. And best improvement in API of the heavy crude o

... Show More
View Publication Preview PDF
Publication Date
Sun May 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Study on the Effect of Ambient Temperature on Absorption Coefficient
...Show More Authors

 Anew mathematical formula was proposed to describe the behavior of the extinction coefficient as a function of ambient temperature and wavelengths for some of infrared materials. This formula was derived depending on some experimental data of transmittance spectrum versus wavelengths for many ambient temperatures. The extensive study of the spectrum characteristics and depending on Bose-Einstein distribution led to derive an equation connecting the extinction coefficient or the absorption coefficient with the ambient temperature and wavelengths of the incident rays. The basic assumption in deriving process is the decreasing in transmittance value with the increasing temperature which is only due to the changing in extinction coeffi

... Show More
View Publication Preview PDF
Publication Date
Wed Aug 02 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Alternative Electrical Properties of (Al -CdSe0.8Te0.2Al) Capacitor at Room Temperature
...Show More Authors

This research aims to prepare an (Al-CdSe0.8Te0.2-Al) capacitor and study the alternating electrical properties of it at room temperature, and study the possibility of using these films in electronical applications.  The A.C. conductivity of as-deposited films have been measured in the frequency range (f =100Hz-400KHz), and it has shown that A.C. conductivity ( σa.c ) increases with the  frequency increasing.  The study of the variation of each of the capacitance and real part of the dielectric constant (Єr ) with frequency has shown that their values decrease with  frequency increasing.             The study of the variation of each of the imaginary p

... Show More
View Publication Preview PDF
Publication Date
Wed Sep 22 2021
Journal Name
The Structural Design Of Tall And Special Buildings
Utilizing I‐shaped shear links as dampers to improve the behavior of concentrically braced frames
...Show More Authors

View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Temperature in Vertical Migration Behavior of Three Species Zooplankton
...Show More Authors

  The present study included  the impact of the follow-up variation in the temperature of aqueous medium in the vertical migration behavior of different groups of Zooplankton, consisted species Cyclops vernalis, Daphnia magna, Diaptomus dilopatus, that have been grown in controlled in terms of light and pH laboratory conditions, so choosing temperature of respectively 16,20,24,28, and 32 ËšC. The result showed a clear change in the migration behavior of testing planktonic species, it was a negative relationship between temperatures arises and individual of D. magna in the water column.While being appositive relationship with individual of C. vernalis and the same with D. dilopatus. Also, the result revealed a different impact

... Show More
View Publication Preview PDF
Publication Date
Mon Apr 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Influence of the Annealing Temperature on optical Properties of (CuInSe2) Thin Films
...Show More Authors

  The Influence of annealing temperature on the optical properties of (CuInSe2) thin films was studied. Thermal evaporation in vacuum technique has been used for films deposited on glass substrates, these films were annealed in vacuum at (100C°, 200C°) for (2 hours). The optical properties were studied in the range (300-900) nm. The obtained results revealed a reduction in energy band gap with annealing temperature . optical parameters such as reflectance, refractive index, extinction coefficient, real and imaginary parts of the dielectric constant, skin depth and optical conductivity are investigated before and after annealing. It was found that all these parameters were affected by annealing temperature.
 

View Publication Preview PDF
Publication Date
Thu Sep 13 2012
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Density and Viscosity of Amino Acid Serine in aqueous dimethyl sulfoxide solution at deferent temperatures
...Show More Authors

Publication Date
Thu Mar 18 2021
Journal Name
Egyptian Journal Of Chemistry
Investigation of the Influence of Membrane Type on the Performance of Microbial Fuel Cell
...Show More Authors

View Publication
Scopus (3)
Crossref (1)
Scopus Clarivate Crossref