Preferred Language
Articles
/
alkej-194
Prediction of Oxygen Mass Transfer Coefficients in Stirred Bioreactor with Rushton Turbine Impeller for Simulated (Non-Microbial) Medias
...Show More Authors

 Abstract

The study of oxygen mass transfer was conducted in a laboratory scale 5 liter stirred bioreactor equipped with one Rushton turbine impeller. The effects of superficial gas velocity, impeller speed, power input and liquid viscosity on the oxygen mass transfer were considered. Air/ water and air/CMC systems were used as a liquid media for this study. The concentration of CMC was ranging from 0.5 to 3 w/v. The experimental results show that volumetric oxygen mass transfer coefficient increases with the increase in the superficial gas velocity and impeller speed and decreases with increasing liquid viscosity. The experimental results of kla were correlated with a mathematical correlation describing the influences of the considered factors (the overall power input and the superficial gas velocity) over the studied rages. The predicted kla values give acceptable results compared with the experimental values. The following correlations were obtained:

Air/water system

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Jun 28 2021
Journal Name
Journal Of The College Of Education For Women
The Developmental Role of Social Work in Reducing Social Extremism:A Field Study in Baghdad University-College of Mass Communication as a Model: محمد حميد علوان
...Show More Authors

This study deals with the role that social work profession plays in all its fields to reduce social extremismat home, or school or within society. The study aims to: examine the historical roots of social work in the Iraqi society, investigate the objectives of the developmental role of social work, review the theories of social extremism, its characteristics, and causes, and to analyze the developmental role of social work to limit social extremism. To meet the objectives of the study, a descriptive analytical approach has been adopted. It involves using the social sampling survey method, i.e., a questionnaire tool in the University of Baghdad community-College of Media. The sample was randomly selected to include (100) students from th

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
CALCULATION BIASES FOR COEFFICIENTS AND SCALE PARAMETER FOR LINEAR (TYPE 1) EXTREME VALUE REGRESSION MODEL FOR LARGEST VALUES
...Show More Authors

Abstract

Characterized by the Ordinary Least Squares (OLS) on Maximum Likelihood for the greatest possible way that the exact moments are known , which means that it can be found, while the other method they are unknown, but approximations to their biases correct to 0(n-1) can be obtained by standard methods. In our research expressions for approximations to the biases of the ML estimators (the regression coefficients and scale parameter) for linear (type 1) Extreme Value Regression Model for Largest Values are presented by using the advanced approach depends on finding the first derivative, second and third.

View Publication Preview PDF
Crossref
Publication Date
Sat Jan 01 2011
Journal Name
Iraqi Journal Of Physics
Calculation of Particle Emission Rates for Nucleon-Induced Reactions with non-Equidistance Spacing Model Dependence
...Show More Authors

Nuclear emission rates for nucleon-induced reactions are theoretically calculated based on the one-component exciton model that uses state density with non-Equidistance Spacing Model (non-ESM). Fair comparison is made from different state density values that assumed various degrees of approximation formulae, beside the zeroth-order formula corresponding to the ESM. Calculations were made for 96Mo nucleus subjected to (N,N) reaction at Emax=50 MeV. The results showed that the non-ESM treatment for the state density will significantly improve the emission rates calculated for various exciton configurations. Three terms might suffice a proper calculation, but the results kept changing even for ten terms. However, five terms is found to give

... Show More
View Publication Preview PDF
Publication Date
Fri Oct 09 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Relationship of maximum bite force with craniofacial morphology, body mass and height in an Iraqi adults with different types of malocclusion
...Show More Authors

Background: Information concerning the maximum bite force in human population is important to clinical orthodontics. Additionally, the influence of bite force on the vertical stability of any treatment result is important. The new position of the dentition should be compatible with the dynamics of the muscular and occlusal forces in all planes. This study was conducted to 1) to measure and compare maximum bite force, body height and weight among normal occlusion and malocclusion groups (cl I,cl II,cl III) in both gender 2) to evaluate the correlation between bite force and craniofacial morphology, body height and weight. Materials and Methods: The sample consists of 100 Iraqi adult subjects aged 18-25 years. It was classified in to four gr

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 18 2025
Journal Name
Soil And Sediment Contamination: An International Journal
Remediation Prediction of Contaminated Soil with Crude Oil Using the Optimized Remediation Method for the Iraqi Environment
...Show More Authors

Large quantities of petroleum-contaminated soil are generated with increased global energy consumption and crude oil production. This theoretical study evaluates the treatment of 1 ton of petroleum-contaminated soil using seven methods: incineration, physical washing, chemical washing, thermal pyrolysis, Fenton-oxidation-pyrolysis, the biological treatment, and asphaltenes. Data were based on experimental results from the Nahran Bin Omar oil lake in Basra Governorate, Iraq, (2019–2021). The methods were compared by waste generation, treatment cost, and duration. Results indicate that using petroleum-contaminated soil as a raw material for asphalt manufacturing is most beneficial since it is sold as a raw material. Incineration is faster a

... Show More
View Publication
Scopus Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Radiation Research And Applied Sciences
Theoretical formula for the cosmic-ray muon attenuation coefficients of Pb, Cu, Zn, and Al
...Show More Authors

View Publication
Crossref (2)
Clarivate Crossref
Publication Date
Fri Dec 31 2021
Journal Name
Iraqi Journal Of Laser
Parametric Optimization for Fatigue Life of 6061-T6 Aluminum Thin Sheets Processed with High-Speed Laser Shock Peening
...Show More Authors

Abstract: Aluminum alloys grade 6061-T6 are characterized by their excellent properties and processing characteristics which make them ideal for varieties of industrial applications under cyclic loading, aluminum alloys show less fatigue life than steel alloys of similar strength. In the current study, a nanosecond fiber laser of maximum pulse energy up to 9.9 mJ was used to apply laser shock peening process (LSP) on aluminum thin sheets to introduce residual stresses in order to enhance fatigue life under cyclic loading Box-Behnken design (BBD) based on the design of experiments (DOE) was employed in this study for experimental design data analysis, model building and optimization The effect of working parameters spot size (ω), scannin

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 04 2015
Journal Name
Journal Of Educational And Psychological Researches
Undesirable behaviors for university students by their instructors view
...Show More Authors

Undesirable behaviors among students  are consider one of the danger problems threating societies and educational and scientific institutions of countries  because its one of the way to express aggression , so the instructors consider one of the most important people could be trust their evaluation and logical view , therefore the present research aimed to :

  1. Recognize undesirable behavior in students of University by the view of their instructors
  2. Measure the level of undesirable behavior in students of university by the view of their instructors
  3. Recognize more common  undesirable behavior in students of University by the view o

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
Cultivation of Microalgae Chlorella vulgaris in Airlift photobioreactor for Biomass Production using commercial NPK Nutrients
...Show More Authors

Airlift reactors are widely used in the chemical and biochemical applications as effective contactors for mass and heat transfer. The main advantages of airlift contactor compared with simple bubble column are ease of construction, low shear rate, high capacity, good mixing and liquid circulation without mechanical agitators and circulating pumps.

In this work, growth characteristics of Chlorella vulgaris microalgae were studied in an internal loop airlift photobioreactor for biomass production. The bioreactor operated under batch and semi-continuous culture mode using commercially available 20:20:20+TE NPK fertilizer as nutrients. The experiments were conducted to evaluate the growth rate and biomass productivity of

... Show More
View Publication Preview PDF
Publication Date
Mon May 01 2017
Journal Name
Applied Mathematics And Computation
Reconstruction of time-dependent coefficients from heat moments
...Show More Authors

View Publication
Scopus (33)
Crossref (17)
Scopus Clarivate Crossref