Preferred Language
Articles
/
alkej-81
Simulation of Oxygen Mass Transfer in an Internal Loop Airlift Reactor with Axial Dispersion Model
...Show More Authors

The effect of superficial gas velocity within the range 0.01-0.164 m/s on gas holdup (overall, riser and down comer), volumetric oxygen mass transfer coefficient, liquid circulation velocity was studied in an internal loop concentric tubes airlift reactor (working volume 45 liters). It was shown that as the usg increases the gas holdup and also the liquid circulation velocity increase. Also it was found that increasing superficial gas velocity lead to increase the interfacial area that increases the overall oxygen mass transfer coefficient. The hydrodynamic experimental results were modeled with the available equations in the literature. The predicted data gave an acceptable accuracy with the empirical data.

The final empirical and predicted data were adopted in a mathematical model for oxygen mass transfer to predict the oxygen profile along the reactor. The predicted results have been validated with the experimental results. The simulated results based on the dispersion model for the riser and down comer and the perfect mixed model for the gas-liquid separator, agreed well with the experimental results over the studied range of operating conditions.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Nov 01 2019
Journal Name
Journal Of Engineering
Prediction of Heat Transfer Coefficient and Pressure Drop in Wire Heat Exchanger Working with R-134a and R-600a
...Show More Authors

An experimental and theoretical works were carried out to model the wire condenser in the domestic refrigerator by calculating the heat transfer coefficient and pressure drop and finding the optimum performance. The two methods were used for calculation, zone method, and an integral method. The work was conducted by using two wire condensers with equal length but different in tube diameters, two refrigerants, R-134a and R-600a, and two different compressors matching the refrigerant type. In the experimental work, the optimum charge was found for the refrigerator according to ASHRAE recommendation. Then, the tests were done at 32˚C ambient temperature in a closed room with dimension (2m*2m*3m). The results showed that th

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Micro encapsulation of Naproxen By Complex Coacervation and Aqueous Colloid Dispersion Part ( 1 )
...Show More Authors

Naproxen is a non steroidal anti inflammatory and antipyretic drug which has local irritation effect  on  the  stomach, and  unpleasant taste,  besides bad   flowability and light sensitivity .The drug was prepared as microcapsules by complex coacervation method using acacia-gelatin coating materials , and aqueous colloid polymer dispersion method ( ACPD ), using ethyl cellulose and sodium alginate coating materials . The results indicated that microcapsules prepared by 2:1  core:wall ratio is the best for both methods, with an average encapsulation efficiency (75%) and avarege yield (90%) .

Moreover the drug release was affected mainly by core : ratio ,pH enviroment and method of microenca

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Determination the dispersion parameters and urbach tail of iron chromate doped PMMA films
...Show More Authors

Films of pure Poly (methyl methacrylate) PMMA and Iron chromate doped PMMA have been prepared using casting method. Transmission and absorptance spectra have been recorded in the wavelength range (300-900) nm, in order to calculate, single oscillator energy, dispersion energy proposed by Wemple - DiDomenico model, average oscillator strength, average oscillator wavelength. The refractive index data at infinite wavelength which was found to obey single oscillator model which was found to increase from 2.27-2.56 as the doping percentage increase. The decreasing in the optical energy gap which was found according to Tauc model were (3.74-3.63) eV , is in good agreement with that obtained by wimple-DiDomenico model. The inverse behavior comp

... Show More
View Publication Preview PDF
Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
EFFCT OF HOOPS AND COLUMN AXIAL LOAD ON SHEAR STRENGTH OF HIGH-STRENGTH FIBER REINFORCED BEAM-COLUMN JOINTS
...Show More Authors

A reinforced concrete frame is referred as "RIGID FRAMES". However, researches indicate that the Beam-Column joint (BCJ) is definitely not rigid. In addition, extensive research shows that failure may occur at the joint instead of in the beam or the column. Joint failure is known to be a catastrophic type which is difficult to repair.
This study was carried out to investigate the effect of hoops and column axial load on the shear strength of high-strength fiber reinforced Beam-Column Joints by using a numerical model based on finite element method using computer program ANSYS (Version 11.0). The variables are: diameter of hoops and magnitude of column axial load.
The theoretical results obtained from ANSYS program are in a good a

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Apr 08 2018
Journal Name
Al-khwarizmi Engineering Journal
Microstructural Characterization and Mechanical Properties of Similar and Dissimilar Al Alloys Joined using Friction Stir Welding
...Show More Authors

The influence of pre- shot peening and welding parameters on mechanical and metallurgical properties of dissimilar and similar aluminum alloys AA2024-T3 and AA6061-T6 joints using friction stir welding have been studied. In this work, numbers of plates were equipped from sheet alloys in dimensions (150*50*6) mm then some of them were exposed to shot peening process before friction stir welding using steel ball having diameter 1.25 mm for period of 15 minutes. FSW joints were manufactured from plates at three welding speeds (28, 40, 56 mm/min) and welding speed 40mm/min was chosen at a rotating speed of 1400 rpm for welding the dissimilar pre- shot plates. Tow joints were made at rotational speed of 1000 rpm and welding speed of 40m/min f

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
The impact of the "Senge" Model of Organizational Learning in the adoption of Total Quality Management principles) Exploratory study in an organization)
...Show More Authors

      This study is concerned with organizational learning and its impact on total quality management in the education sector. Organizational learning is a process that provides the educational sector with the ability to adapt and respond rapidly to developments and changes in a better way according to its main dimensions (Mental Models, Personal Mastery, Team Learning, Shared Vision, System Thinking) by adopting the philosophy of Total Quality Management (TQM) in accordance with its basic dimensions (leadership, customer satisfaction, participation of workers, continuous improvement, training and education). The main purpose of this study is to know (the impact of the Senge model of organizational learni

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Oct 17 2018
Journal Name
Journal Of Economics And Administrative Sciences
The impact of the "Senge" Model of Organizational Learning in the adoption of Total Quality Management principles) Exploratory study in an organization)
...Show More Authors

      This study is concerned with organizational learning and its impact on total quality management in the education sector. Organizational learning is a process that provides the educational sector with the ability to adapt and respond rapidly to developments and changes in a better way according to its main dimensions (Mental Models, Personal Mastery, Team Learning, Shared Vision, System Thinking) by adopting the philosophy of Total Quality Management (TQM) in accordance with its basic dimensions (leadership, customer satisfaction, participation of workers, continuous improvement, training and education). The main purpose of this study is to know (the impact of the Senge model of organizational learni

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Nov 17 2020
Journal Name
Annals Of Tropical Medicine And Public Health
Correlation Study of Aromatase, Some Sex Hormones, and Body Mass Index Among Iraqi Patients with Polycystic Ovary Syndrome
...Show More Authors

View Publication
Scopus (1)
Scopus Crossref
Publication Date
Wed Aug 21 2019
Journal Name
Al-khwarizmi Engineering Journal
Design and Optimization of a Surface-Mounted Permanent-Magnet Linear Synchronous Motor with Maxwell ANSYS
...Show More Authors

Linear motor offers several features in many applications that require linear motion. Nevertheless, the presence of cogging force can deteriorate the thrust of a permanent magnet linear motor. Using several methodologies, a design of synchronous single sided linear iron-core motor was proposed. According to exact formulas with surface-mounted magnets and concentrated winding specification, which are relying on geometrical parameters. Two-dimensional performance analysis of the designed model and its multi-objective optimization were accomplished as a method to reduce the motor cogging force using MAXWELL ANSYS. The optimum model design results showed that the maximum force ripple was approximatrly reduced by 81.24%compared to the origina

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Tue Mar 30 2021
Journal Name
Baghdad Science Journal
Fixed Point Theorems in General Metric Space with an Application
...Show More Authors

   This paper aims to prove an existence theorem for Voltera-type equation in a generalized G- metric space, called the -metric space, where the fixed-point theorem in - metric space is discussed and its application.  First, a new contraction of Hardy-Rogess type is presented and also then fixed point theorem is established for these contractions in the setup of -metric spaces. As application, an existence result for Voltera integral equation is obtained.  

View Publication Preview PDF
Scopus (13)
Scopus Clarivate Crossref