Preferred Language
Articles
/
alkej-271
Modeling of Mass Transfer Coefficient in Rotating Biological Contactor with Perforated Discs (RPBC)
...Show More Authors

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.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Jun 29 2018
Journal Name
Journal Of Engineering
Experimental Investigation of Short Square Normal and Hybrid Fiber Reactive Powder Concrete Columns Subjected to Chloride Solution Attack
...Show More Authors

In this research, the structural behavior of reinforced concrete columns made of normal and hybrid reactive powder concrete (hybrid by steel and polypropylene fibers) subjected to chloride salts with concentration was 8341.6 mg/l. The study consists of two parts, the first one is experimental study and the second one is theoretical analysis.  Three main variables were adopted in the experimental program; concrete type, curing type and loading arrangement. Twenty (120x120x1200) mm columns were cast and tested depending on these variables. The samples were reinforced using two different bars; Ø8 for ties and Ø12 with minimum longitudinal reinforcement (0.01Ag). The specimens were divided into two main groups based o

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
The Structural and Optical Properties of Hydrogenated and Nitrogenated a-Si0.1Ge0.9 and a-Si0.1Ge0.9:3% B Thin Films
...Show More Authors

It is shown that pure and 3% boron doped a-Si0.1Ge0.9:H and a-Si0.1Ge0.9:N thin films
could be prepared by flash evaporation processes. The hydrogenation and nitrogenation
are very successful in situ after depositing the films. The FT-IR analysis gave all the
known absorbing bonds of hydrogen and nitrogen with Si and Ge.
Our data showed a considerable effect of annealing temperature on the structural and
optical properties of the prepared films. The optical energy gap (Eopt.) of a-Si0.1Ge0.9
samples showed to have significant increase with annealing temperature (Ta) also the
refractive index and the real part of dielectric constant increases with Ta, however the
extinction coefficient and imaginary part of dielect

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Aip Conference Proceedings
Study of (Zn0.7 Mn0.3-x Ag0.3 Fe2O4) ferrite nanoparticles synthesized by auto combustion method for NO2 gas sensing
...Show More Authors

View Publication
Scopus (3)
Crossref (1)
Scopus Crossref
Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
Synthesis and Structural Determination of 6-O-prop-2-ynyl-1,2:3,4-di-O-Isopropylidene-α-D-Galactose
...Show More Authors

In this work, an important sugar alkynyl ether has been synthesized in two subsequent steps starting from commercially available D-galactose (3). This kind of compounds is highly significant in the synthesis of biologically active molecules such as 1,2,3-triazole and isoxazoles. In the first step, galactose (3) was reacted with acetone in the presence of anhydrous copper (II) sulfate to produce 1,2:3,4-di-O-isopropylidene-α-D-galactose (4) in good yield. The latter was reacted with excess of 3-bromoprop-1-yne in DMF in the presence of NaOH pellets to afford the target molecule 5 in a very good yield. The temperature of this step is crucial in determining the reaction yi

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Thu Feb 29 2024
Journal Name
Iraqi Journal Of Science
Finding the Exact Solution of Kepler’s Equation for an Elliptical Satellite Orbit Using the First Kind Bessel Function
...Show More Authors

     In this study, the first kind Bessel function was used to solve Kepler equation for an elliptical orbiting satellite. It is a classical method that gives a direct solution for calculation of the eccentric anomaly. It was solved for one period from (M=0-360)° with an eccentricity of (e=0-1) and the number of terms from (N=1-10). Also, the error in the representation of the first kind Bessel function was calculated. The results indicated that for eccentricity of (0.1-0.4) and (N = 1-10), the values of eccentric anomaly gave a good result as compared with the exact solution. Besides, the obtained eccentric anomaly values were unaffected by increasing the number of terms (N = 6-10) for eccentricities (0.8 and 0.9). The Bessel

... Show More
View Publication
Scopus (5)
Crossref (2)
Scopus Crossref
Publication Date
Sat Nov 15 2025
Journal Name
Cell Biochemistry And Biophysics
Green Synthesis of Platinum Nanoparticles Using Aqueous Broccoli Extract for Antimicrobial, Antioxidant, Wound Healing, Antidiabetic, and Anticancer Applications
...Show More Authors

Platinum nanoparticles (PtNPs) exhibit promising biomedical properties, but concerns about biocompatibility and synthesis-related toxicity remain. This study aimed to develop eco-friendly PtNPs using aqueous broccoli extract as a natural reducing and stabilizing agent, and to assess their multifunctional biomedical potential. PtNPs were synthesized through sonochemical reduction of K₂PtCl₆ in broccoli extract, followed by purification and comprehensive physicochemical characterization. UV–Vis confirmed nanoparticle formation at 253 nm, while XRD and FTIR analyses verified the crystalline FCC structure and phytochemical capping. TEM revealed mainly spherical PtNPs with an average core size of 14.83 ± 7.67 nm. Conversely, DLS showe

... Show More
View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Jul 01 2023
Journal Name
Iop Conference Series: Earth And Environmental Science
The Effect of Dry Farming and Water Stress under Subsurface Drip Irrigation System on Water and Rice Productivity
...Show More Authors
Abstract<p>A field experiment was carried out during the 2020 season at the College of Agricultural Engineering/ University of Baghdad, Al-Jadriya to evaluate the effect of dry farming when applying water stress under the subsurface drip irrigation system on water productivity and rice yield. The experiment was conducted with three levels of irrigation water stress when 10, 20 and 40% of the available water was depleted and in three dimensions between drip lines 10, 15 and 20 cm. The experiment was designed according to a randomized complete block design, according to the split plot design, with three replications. Determine the depth of irrigation water depending on the moisture depletion of th</p> ... Show More
View Publication
Scopus Crossref
Publication Date
Sat Oct 19 2024
Journal Name
Baghdad Science Journal
Synthesis, Characterization and Studying Thermal Analysis for Complexes of Some Metal Ions and Determining Their Activity as Antioxidants
...Show More Authors

وفقأ للدراسات السابقة تم تحضير ليكاند آزو جديد (ن-(3-اسيتايل-2-هيدروكسي-5-مثيل-فنيل)ن-(4-كاربوكسي-سايكلوهكسيل مثيل)-ملح الدايازونيوم) وبعد التحقق من الصيغة المقترحة وفق نتائج التحاليل وبعد استخدام الليكاند لتحضير سلسلة ن المعقدات باستخدام نسب مولية متساوية (1:1) من الليكاند وتفاعلها مع كل من املاح المنغنيز والكوبلت والنيكل والنحاس والخارصين وبعد التحقق وفق تقنيات التحاليل الطيفية والتشخيصية(الاشعة فوق البنف

... Show More
View Publication
Scopus (3)
Scopus Clarivate Crossref
Publication Date
Sat Mar 21 2020
Journal Name
Electronic Journal Of General Medicine
The Possible Immunological Pathways for the Variable Immunopathogenesis of COVID—19 Infections among Healthy Adults, Elderly and Children
...Show More Authors

View Publication
Scopus (113)
Crossref (121)
Scopus Clarivate Crossref
Publication Date
Sat Aug 19 2023
Journal Name
Silicon
Structural and Hardness Characteristics of Silicon Nitride Thin Films Deposited on Metallic Substrates by DC Reactive Sputtering Technique
...Show More Authors

View Publication
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref