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alkej-271
Modeling of Mass Transfer Coefficient in Rotating Biological Contactor with Perforated Discs (RPBC)
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Abstract

 In order to make an improvement associated with rotating biological contactor (RBC), a new design of biofilm reactor called as Rotating perforated disc biological contactor (RPBC) was developed in which the rotating discs are perforated. The transfer of oxygen from air to wastewater was investigated. Mass-transfer coefficient (KLa)  in the liquid phase was determined by measuring  the rate transfer of oxygen.  A   laboratory scale of (RPBC) consisted of a semicircular trough was used with a working capacity of 40 liters capacity of liquid. Synthetic wastewater was used as a liquid phase, while air was used as a gas phase.

The effects of many parameters on the liquid phase mass transfer coefficient (KLa) were investigated. These parameters are; the disc rotational speed (N), the pore diameter (d) and clearance between the discs(C). It was found that the value of KLa was increased as the rotation speed (N) increased, and as  the diameter of the pores in  the disc  (d) increased. While the values of (KLa) was decreased continuously with increasing the clearance(C). Suitable correlation was developed for estimating mass transfer coefficient (KLa) in this type of bioreactor.

 Keywords: Rotating biological contactor, Mass transfer coefficient, Wastewater treatment.

 

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Publication Date
Wed Jan 30 2019
Journal Name
Journal Of The College Of Education For Women
Creative thinking and its relationship to solving the problems of professional skills For kindergarten teachers
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Current search aims to identify the creative thinking of the kindergarten teachers and
solving professional problems among kindergarten teachers skills, and whether the level of
creative thinking in solving professional problems, according on marital status years of
service academic achievement of teachers as well as to identify the correlation between the
two variables the current sample consisted of (300) teachers to achieve the objectives of the
stndy , the researcher used two measures, one to measure creative thinking and the other to
measure the solution to the problems of professional kindergarten teachers skills. It has been
shown. validity and reliability of the two measures. The present stndy aims to identif

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Publication Date
Sun Feb 22 2026
Journal Name
International Journal Of Data And Network Science
Multi-objective of wind-driven optimization as feature selection and clustering to enhance text clustering
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Text Clustering consists of grouping objects of similar categories. The initial centroids influence operation of the system with the potential to become trapped in local optima. The second issue pertains to the impact of a huge number of features on the determination of optimal initial centroids. The problem of dimensionality may be reduced by feature selection. Therefore, Wind Driven Optimization (WDO) was employed as Feature Selection to reduce the unimportant words from the text. In addition, the current study has integrated a novel clustering optimization technique called the WDO (Wasp Swarm Optimization) to effectively determine the most suitable initial centroids. The result showed the new meta-heuristic which is WDO was employed as t

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Publication Date
Sat Jan 01 2022
Journal Name
Indonesian Journal Of Electrical Engineering And Computer Science
Increasing validation accuracy of a face mask detection by new deep learning model-based classification
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During COVID-19, wearing a mask was globally mandated in various workplaces, departments, and offices. New deep learning convolutional neural network (CNN) based classifications were proposed to increase the validation accuracy of face mask detection. This work introduces a face mask model that is able to recognize whether a person is wearing mask or not. The proposed model has two stages to detect and recognize the face mask; at the first stage, the Haar cascade detector is used to detect the face, while at the second stage, the proposed CNN model is used as a classification model that is built from scratch. The experiment was applied on masked faces (MAFA) dataset with images of 160x160 pixels size and RGB color. The model achieve

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Publication Date
Sat Apr 01 2023
Journal Name
Chemical Methodologies
A Novel Design for Gas Sensor of Zinc Oxide Nanostructure Prepared by Hydrothermal Annealing Technique
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Publication Date
Wed Dec 02 2020
Journal Name
Iraqi Journal Of Applied Physics
Characterization of Multilayer Highly-Pure Metal Oxide Structures Prepared by DC Reactive Magnetron Sputtering Technique
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In this work, multilayer nanostructures were prepared from two metal oxide thin films by dc reactive magnetron sputtering technique. These metal oxide were nickel oxide (NiO) and titanium dioxide (TiO2). The prepared nanostructures showed high structural purity as confirmed by the spectroscopic and structural characterization tests, mainly FTIR, XRD and EDX. This feature may be attributed to the fine control of operation parameters of dc reactive magnetron sputtering system as well as the preparation conditions using the same system. The nanostructures prepared in this work can be successfully used for the fabrication of nanodevices for photonics and optoelectronics requiring highly-pure nanomaterials.

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Publication Date
Wed Nov 16 2022
Journal Name
F1000research
Pattern changes of cutaneous dermatoses among Iraqi women preceding and during the COVID-19 pandemic
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Background: We compared the pattern of cutaneous dermatoses among Iraqi females of all ages between 4 months preceding the coronavirus disease 2019 (COVID-19) pandemic, and the same months 1 year later within the COVID-19 pandemic.

Methods: This was a cross-sectional study, that targeted all female patients attending an outpatient clinic for dermatology and venereology in Al-Kindy teaching hospital, Baghdad between October 2019 to the end of January 2020, and the same 4-month duration 1 year later (October 2020 to the end of January 2021) after the COVID-19 peak period had passed and there was no or partial curfew to exclude seasonal impact.

Results

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Publication Date
Sat Feb 09 2019
Journal Name
Journal Of The College Of Education For Women
١١٦ Academic Specialization and its relationship to job performance of The officials ofBaghdad University Presidency
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The aims of this research is to investigate : The nature of academic specialization of the officials of Baghdad University Presidency , Level of job performance of the officials of Baghdad University Presidency through job performance appraisal form per year , Differences in the levels of job performance of the officials of Baghdad university presidency , according to the variables (sex , academic specialization , the current work , the duration between the date of graduation and the date of appointment , service duration) , The relationship of academic specialization of the officials of Baghdad university presidencywith their job performance . The researcher has followed the analytical descriptive mode to achieve the aims of this resear

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Publication Date
Mon Apr 24 2023
Journal Name
Materials Research Innovations
Surface modification of poly(methyl methacrylate)-sulphadiazine complexes as self photostabilizer against Ultraviolet (UV) Irradiation
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Publication Date
Sat Apr 01 2023
Journal Name
Baghdad Science Journal
Characterization of a novel pathway for xanthene degradation by the engineered strain Sphingobium yanoikuyae B1DR
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Polyaromatic hydrocarbons (PAHs) are a group of aromatic compounds that contain at least two rings. These compounds are found naturally in petroleum products and are considered the most prevalent pollutants in the environment. The lack of microorganism capable of degrading some PAHs led to their accumulation in the environment which usually causes major health problems as many of these compounds are known carcinogens. Xanthene is one of the small PAHs which has three rings. Many xanthene derivatives are useful dyes that are used for dyeing wood and cosmetic articles. However, several studies have illustrated that these compounds have toxic and carcinogenic effects. The first step of the bacterial degradation of xanthene is conducted by d

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Publication Date
Tue Jul 01 2014
Journal Name
Political Sciences Journal
Political pluralism between rejection and acceptance Astrobiological study of the most prominent contemporary Islamic trends
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التعددية السياسية بين الرفلض والقبول دراسة نظرية لأبرز الاتجاهات الاسلامية المعاصرة

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