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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
Tue Sep 28 2021
Journal Name
Journal Of The College Of Education For Women
Efficiency of Infrastructure Services in Khor Al-Zubair City (Iraq) Firas Sami Abdulaziz Alqatrani1 and Amira
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The aim of the research is to demonstrate the concept, characteristics, efficiency and adequacy of infrastructure in Khor Al-Zubair, as it represents an important benchmark for judging the development of the city. The researchers thus aim to measure the efficiency, adequacy and personal impression of each service in Khor Al-Zubair city and its residential neighborhoods. To meet this objective, the researchers used the descriptive and analytical approach that involves randomly distributing a questionnaire with specific questions to the neighbors of the city. The study has reached a set of results and recommendations that contribute to addressing the problems to the sector of infrastructure services in the city, such as: the per capita sha

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Publication Date
Sun Dec 31 2000
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Heat Transfer in Bubble Column Contactors with immersed Coiled Heater
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Publication Date
Fri Mar 01 2019
Journal Name
Applied Acoustics
Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths
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Publication Date
Sat Jun 20 2020
Journal Name
Neuroquantology
Study of Charge Flow Coefficient Au Metal with a - NPD Molecule Dye
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The coefficient of charge transfer at heterogeneous devices of Au metal with a well-known dyeis investigations using quantum model.Four different solvent are used to estimation the effective transition energy. The potential barrier at interface of Au and dye has been determined using effective transition energy and difference between the Fermi energy of Au metal and ionization energy of dye. A possible transfer mechanism cross the potential barrier dyeand coupling strength interaction between the electronic levels in systems of Au and is discussed.Differentdata of effective transition energy and potential barrier calculations suggest that solvent is more suitable to binds Au with dye.

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Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Using Multidimensional Contingency Coefficient to Discrimination Arabic Poems for Sample of Poets
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The purpose of this paper to discriminate between the poetic poems of each poet depending on the characteristics and attribute of the Arabic letters. Four categories used for the Arabic letters, letters frequency have been included in a multidimensional contingency table and each dimension has two or more levels, then contingency coefficient calculated.

The paper sample consists of six poets from different historical ages, and each poet has five poems. The method was programmed using the MATLAB program, the efficiency of the proposed method is 53% for the whole sample, and between 90% and 95% for each poet's poems.

 

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Publication Date
Sun Feb 01 2009
Journal Name
Materials Science And Engineering: B
Microstructure, electrical properties and Hall coefficient of europium-doped Li–Ni ferrites
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Publication Date
Sun Sep 01 2019
Journal Name
Journal Of Physics: Conference Series
Recovery of temporal coefficient for heat equation from non-local overdetermination conditions
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Abstract<p>Recovery of time-dependent thermal conductivity has been numerically investigated. The problem of identification in one-dimensional heat equation from Cauchy boundary data and mass/energy specification has been considered. The inverse problem recasted as a nonlinear optimization problem. The regularized least-squares functional is minimised through lsqnonlin routine from MATLAB to retrieve the unknown coefficient. We investigate the stability and accuracy for numerical solution for two examples with various noise level and regularization parameter.</p>
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Publication Date
Wed Mar 01 2023
Journal Name
Iraqi Journal Of Physics
Calculation Mars – Earth distance and Mars orbital elements with Julian date
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In this paper, the Mars orbital elements were calculated. These orbital elements—the major axis, the inclination (i), the longitude of the ascending node (W), the argument of the perigee (w), and the eccentricity (e)—are essential to knowing the size and shape of Mars' orbit. The quick basic program was used to calculate the orbital elements and distance of Mars from the Earth from 25/5/1950 over 10000 days. These were calculated using the empirical formula of Meeus, which depended on the Julian date, which slightly changed for 10000 days; Kepler's equation was solved to find Mars' position and its distance from the Sun. The ecliptic and equatorial coordinates of Mars were calculated. The distance between Mars and the center of the E

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Publication Date
Tue Jan 01 2019
Journal Name
Journal Of The College Of Languages (jcl)
Exploitation of the Democratization of Language in the Mass Media: Тенденция к демократизации языка в сми
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      In the present paper, the features of democratization of vocabulary in the language of mass media are tackled. Particularly, the functions of this phenomenon in the context of language as an ontological reality are analysed. As well, the growing role  of the language of the media, and the language of politics as an integral part pertaining to it, is noted. Further, attention is paid to the excessive saturation of the language of the media along with the literary language, by means of evaluation which may include negative results.

     In this concern, scholars had different views, specifically in relation to the use of colloquial vocabulary along with some vernacular profess

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Publication Date
Wed Feb 20 2019
Journal Name
Political Sciences Journal
A political perusal of Initiations in Declaring Middle East a District vacant of mass Destruction weapons
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A political perusal of Initiations in Declaring Middle East a District vacant of mass Destruction weapons

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