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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 Dec 30 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Heat Transfer Efficiency of Different Composite Insulators
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This research aims to investigate the thermal performance of different thermal composite insulators, wrapped around a closed-loop copper pipe (CLP). To achieve this aim a system was designed and manufactured. It is consisted of closed water tank insulated by Rock Wool, and supplied with two electric heaters, two thermostat, a flow meter, a water pump, digital temperature scales, and four series of (CLP).
Six insulators were prepared namely; composites of Impregnated Fiberglass with Elastoclad and foaming Rubber (FER), Impregnated Fiberglass with Elastoclad resin and Polymeric Membrane (FEM), Impregnated Fiberglass with Polyurethane thermoset resin and Foaming Rubber (FUR), Impregnated Fiberglass with Polyurethane thermoset resin and P

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Publication Date
Fri Dec 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Effect of the Quality of Accounting Information on the Efficiency of Investment Decisions
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Abstract

The entities responsible for regulating the financial market are seeking to provide high quality accounting information, to provide appropriate protection to investors, and thus encourage them and attract them to increase their investments. the research reached several conclusion, the most prominent of which comes  :-

1-The production of high quality accounting information reduces investment costs and costs of processing accounting information.

2- The production of high quality accounting information helps investors identify the best investment opportunities.

3- The results of the statistical analysis showed that there is significant

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Publication Date
Sun May 01 2016
Journal Name
Journal Of Engineering
Experimental Investigation of Convection Heat Transfer Enhancement in Horizontal Channel Provided with Metal Foam Blocks
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Convection heat transfer in a horizontal channel provided with metal foam blocks of two numbers of pores per unit of length (10 and 40 PPI) and partially heated at a constant heat flux is experimentally investigated with air as the working fluid. A series of experiments have been carried out under steady state condition. The experimental investigations cover the Reynolds number range from 638 to 2168, heat fluxes varied from 453 to 4462 W/m2, and Darcy number 1.77x10-5, 3.95x10-6. The measured data were collected and analyzed. Results show that the wall temperatures at each heated section are affected by the imposed heat flux variation, Darcy number, and Reynolds number variation. The var

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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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Publication Date
Thu Feb 07 2019
Journal Name
Journal Of The College Of Education For Women
EFFICIENCY SPIHT IN COMPRESSION AND QUALITY OF IMAGE
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Image compression is an important tool to reduce the bandwidth and storage
requirements of practical image systems. To reduce the increasing demand of storage
space and transmission time compression techniques are the need of the day. Discrete
time wavelet transforms based image codec using Set Partitioning In Hierarchical
Trees (SPIHT) is implemented in this paper. Mean Square Error (MSE), Peak Signal
to Noise Ratio (PSNR) and Maximum Difference (MD) are used to measure the
picture quality of reconstructed image. MSE and PSNR are the most common picture
quality measures. Different kinds of test images are assessed in this work with
different compression ratios. The results show the high efficiency of SPIHT algori

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Publication Date
Sun Jan 01 2023
Journal Name
Acta Facultatis Medicae Naissensis
A correlation between body mass index and refractive errors
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Background. Body mass index (BMI) is a person's weight in kilograms (or pounds) divided by the square of height in meters (or feet). Obesity affects a wide spectrum of age groups, from the young to the elderly, and there are several eye diseases related to obesity like diabetic retinopathy, floppy eyelid syndrome, retinal vein occlusion, stroke-related vision loss, age-related macular degeneration, and possibly, refractive errors. Refractive errors (RE) are optical imperfections related to the focusing ability of the eye and are the main cause of visual impairment which may result in missed education and employment opportunities, lower productivity and impaired quality of life. Aim. The study aimed to find an association between bod

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Publication Date
Sat Jan 01 2022
Journal Name
International Journal Of Medical Toxicology & Legal Medicine
The relationship between body mass index and asthma control
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Asthma and obesity are both a major public health problems affecting large numbers of individuals across the globe. Link between obesity and asthma is now considered as a recognized fact, and many epidemiological studies, found that overweight and obese people had a higher chance of developing asthma, with more severe symptoms. Assessment of the relationship between body mass index and asthma control. A cross-sectional study, that included 100 patients diagnosed with asthma, attending the respiratory disease consultatory unit at Baghdad teaching hospital. Body mass index was calculated by (BMI= weight in Kg/Height in m2), and Asthma control was assessed using asthma control test questionnaire forma. Statistical analysis done using, Test of

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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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