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Estimation of Volumetric Mass Transfer Coefficient in Bioreactor
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This study is concentrated to investigate the effects of aeration and stirring speed on the volumetric mass transfer coefficient (KLa). A dynamic technique was used in estimating KLa values in order to achieve the aim of this study.

This study was done in 10L bioreactor by using two medias:-

  1. Dionized water
  2. Xanthan solution (1 g /L)

Moreover, the research covered a comparison between the obtained values of KLa.

The Xanthan solution was used because of its higher viscosity in comparison with water. It behaves similarly to the cultivation medium when organisms are cultivated in a bioreactor. Growth of organisms in the reactor leads to a change in the viscosity of the medium which affects the mass transfer.

Two variables, the effect of air flow rate (3-20 L/min) and the effect of stirring speed (250-700rpm) on KLa value were studied. Other parameters such as temperature, liquid volume, and stirrer shape and stirrer position were held constant; the results demonstrated an increase in KLa – value and mass transfer with increasing stirrer speed. Thus at higher speed, better dispersion of the bubbles was obtained. Therefore, that increased the surface / volume ratio which increased the mass transfer area i.e. KLa value.

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Publication Date
Wed Jan 01 2020
Journal Name
Annals Of Tropical Medicine And Public Health
EFFECT OF EUCALYPTUS AND MYRTUS EXTRACTS IDENTIFICATION BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY ON SOME SPECIES OF CANDIDA AS A MODEL OF MEDICAL PLANTS
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Publication Date
Wed Jun 10 2020
Journal Name
Annals Of Tropical Medicine & Public Health
EFFECT OF EUCALYPTUS AND MYRTUS EXTRACTS IDENTIFICATION BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY ON SOME SPECIES OF CANDIDA AS A MODEL OF MEDICAL PLANTS
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The study showed that all extracts (aqueous, ethanolic and acetonic) of the leaves of Eucalyptus and Myrtus plants had a inhibitory effect on the growth of all types of yeasts studied, acetone extract recorded the highest inhibition of yeastat 100ppm concentration,The inhibition was 35mm, 34mm, 24mm and 20mm for Candida parapsilosis, Candida glabrata, Candida tropicalis and Candida albicans respectively, The experiments above showed the least significant differences at 0.05 level.The results ofE. Cammldulensis ethanolic tincture analysis has shown the presence of 44 biologically active substances. The main Eucalyptus leaves component was: 2-Bicyclo (2-2.1) heptanol (12.37%), Ledol (8.23%),1,2,4- Benzenetriol (8.45%) and that contain spathul

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Publication Date
Tue Dec 31 2024
Journal Name
Sports Culture
The effect of boot camp-style preventive exercises in enhancing the efficiency of the ankle joint and reducing its injury to young triple jump players
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The research aims to prepare preventive exercises in the boot camp style to enhance the efficiency of the ankle joint and reduce its injuries for young triple jump players, and to determine the effect of preventive exercises on improving the efficiency of the ankle joint. The researchers assumed statistically significant differences between the pre-and posttests in the research variables. The experimental approach was adopted to suit it, and the research sample was chosen from young triple jump players. The preventive approach prepared by the researchers was applied to the sample, and it included preventive exercises in the boot camp style with and without tools. The researchers concluded that preventive exercises in a boot camp style have

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Publication Date
Sun Dec 01 2019
Journal Name
2019 First International Conference Of Computer And Applied Sciences (cas)
A Comparison for Some of the estimation methods of the Parallel Stress-Strength model In the case of Inverse Rayleigh Distribution
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Publication Date
Sun Aug 30 2020
Journal Name
Periodicals Of Engineering And Natural Sciences (pen)
Kernel estimation of returns of retirement funds of employers based on monetary earnings (subscriptions and compensation) via regression discontinuity in Iraq
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Regression Discontinuity (RD) means a study that exposes a definite group to the effect of a treatment. The uniqueness of this design lies in classifying the study population into two groups based on a specific threshold limit or regression point, and this point is determined in advance according to the terms of the study and its requirements. Thus , thinking was focused on finding a solution to the issue of workers retirement and trying to propose a scenario to attract the idea of granting an end-of-service reward to fill the gap ( discontinuity point) if it had not been granted. The regression discontinuity method has been used to study and to estimate the effect of the end -service reward on the cutoff of insured workers as well as t

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Publication Date
Mon Mar 27 2023
Journal Name
8th Engineering And 2nd International Conference For College Of Engineering – University Of Baghdad: Coec8-2021 Proceedings
Experimental study of natural convection heat transfer on an enclosure partially filled porous medium heated from below by constant heat flux
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This study reports on natural convection heat transfer in a square enclosure of length (L=20 cm) with a saturated porous medium (solid glass beads) having same fluid (air) at lower horizontal layer and free air fill in the rest of the cavity's space. The experimental work has been performed under the effects of heating from bottom by constant heat flux q=150,300,450,600 W/m2 for four porous layers thickness Hp (2.5,5,7.5,1) cm and three heaters length δ(20,14,7) cm. The top enclosure wall was good insulated and the two side walls were symmetrically cooled at constant temperature. Four layers of porous media with small porosity, Rayleigh number range (60.354 - 241.41) and (Da) 3.025x10-8 has been investigated. The obtained data of temperatu

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Multiwavelet and Estimation by Interpolation Analysis Based Hybrid Color Image Compression
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Nowadays, still images are used everywhere in the digital world. The shortages of storage capacity and transmission bandwidth make efficient compression solutions essential. A revolutionary mathematics tool, wavelet transform, has already shown its power in image processing. The major topic of this paper, is improve the compresses of still images by Multiwavelet based on estimation the high Multiwavelet coefficients in high frequencies sub band  by interpolation instead of sending all Multiwavelet coefficients. When comparing the proposed approach with other compression methods Good result obtained

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Publication Date
Mon Feb 20 2017
Journal Name
Proceedings Of The 5th International Conference On Communications And Broadband Networking
Bit precision and Cyclic prefix effect on OFDM Power Consumption Estimation
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Publication Date
Wed Jan 01 2014
Journal Name
Proceedings Of The Aintec 2014 On Asian Internet Engineering Conference - Aintec '14
LTE Peak Data Rate Estimation Using Modified alpha-Shannon Capacity Formula
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Publication Date
Fri Jul 01 2011
Journal Name
3rd European Workshop On Visual Information Processing
Mean Predictive Block Matching (MPBM) for fast block-matching motion estimation
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