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Heat Transfer and Hydrodynamic in Internal Jacket Airlift Bioreactor with Microbubble Technology
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   Integration of laminar bubbling flow with heat transfer equations in a novel internal jacket airlift bioreactor using microbubbles technology was examined in the present study. The investigation was accomplished via Multiphysics modelling to calculate the gas holdup, velocity of liquid recirculation, mixing time and volume dead zone for hydrodynamic aspect. The temperature and internal energy were determined for heat transfer aspect.

   The results showed that the concentration of microbubbles in the unsparged area is greater than the chance of large bubbles with no dead zones being observed in the proposed design.  In addition the pressure, due to the recirculation velocity of liquid around the draft tube, increased the retention time of microbubbles in the same area.  

   Thus it was expected that their effect on mass and heat transfer phenomena would be positive for biological applications. For example the gas fraction volume of microbubble in the downcomer region is 0.0063, while with fine bubble diameter of 1 mm, this region was free from any bubble. Furthermore, the velocity of liquid in the center of ring diffuser would be 0.175 m/s, if the sparging system operated with bubble diameter of 100 micrometer, whilst would be 0.035 m/s with fine bubble diameter of 1 mm.

   The study also proved the importance of bubble diameter on the heat transfer in gas and liquid phases in the proposed design. Microbubbles gave greater responsiveness to stability and homogeneity in all parts of the bioreactor. Finally, this study concluded the efficiency of the proposed design with the microbubbles technology thermally and hydrodynamically.

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Publication Date
Tue Jan 02 2018
Journal Name
Journal Of Educational And Psychological Researches
The effect of recent technology on university students’ skills
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The study aims to identify the students’ attitudes toward recent techniques’ use in teaching; using power point software and data show to facilitate teaching approaches as well as following the approach of lecture in giving subjects, do these techniques facilitate, increase, and tackle the difficulties of subjects, do these attitudes positive or negative?, and to what extent these techniques raise up students’ motivation.   

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Publication Date
Tue Nov 05 2019
Journal Name
Cardiff University
Technology development for nanoscale InSb quantum split-gate structures
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Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
Influence of Internal Sulfate Attack on Some Properties of High Strength Concrete
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One of the most important problems that faces the concrete industry in Iraq is the deterioration due to internal sulfate attack , since it  reduces the compressive strength and increases the expansion of concrete. Consequently, the concrete structure may be damage .The effects of total and total effective sulfate contents on high strength concrete (HSC) have been studied in the present study.

The research studied the effect of sulfate content in cement , sand and gravel , as well as comparing  the total sulfate content with the total effective SO3 content. Materials used were divided into two groups of SO3 in cement ,three groups of SO3 in sand ,and two groups of SO

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Publication Date
Thu Jun 01 2023
Journal Name
South Asian Journal Of Social Sciences & Humanities
The Impact of University Internal Environment, Development Talents on Sustainable Competitive Advantage.
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There is a need to make serious efforts For Iraqi universities to be in the ranks of advanced universities in the world. This requires attracting teaching talents and providing an incubating environment for them. Therefore, the objective of the research was to explore the influence of (the environment, the development of talents) on sustainable competitive advantages. The research followed the descriptive approach and used the quantitative analysis method. Almaqaal university is the field of study. The study sample size (of 76 people), from almaaqal university teachers, and the sample comprised the available staff specialized in the field of Teaching and research. The questionnaire was utilised as a data collection tool and (spss) program w

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Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
" The Effect of the Auditor's Experience on the Quality of Internal Audit "
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The importance of internal audit in the growing demand for services in the public and private economic units, and in the rapid growth of its systems professional, has also been recognition of the importance of internal audit quality and the quality of information provided in a long time, as well as the importance of achieving the greatest possible quality in his work to reduce accounting risks of financial reports misleading or fraudulent, which is one of the important features of the audit.

The internal audit quality are linked with the ability of auditors to detect errors in the financial statements, and their willingness to express an opinion technical neutral and non-aligned based on the results of th

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Publication Date
Mon Nov 01 2021
Journal Name
Iop Conference Series: Earth And Environmental Science
Use of Thermostone Waste Aggregates for Internal Curing of Reactive Powder Concrete
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Abstract<p>The concrete need curing for cement hydration that is a chemical reaction in each step require water supply throughout the time period. The traditional concrete cured by external method that prevents the concrete surface dry so that keeping the concrete mixture wet and warm. The internal curing was adopted in normal and high strength concrete such as reactive powder concrete. In present paper, experimental approach is to study the mechanical properties of reactive powder concrete cured internally with thermostone material. The materials that adopted to evaluate and find out the influences of the internal curing on the mechanical properties of reactive powder concrete is focused with d</p> ... Show More
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Publication Date
Sat Aug 01 2015
Journal Name
Journal Of Engineering
Influence of Internal Sulfate Attack on Some Properties of High Strength Concrete
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One of the most important problems that faces the concrete industry in Iraq is the deterioration due to internal sulfate attack , since it reduces the compressive strength and increases the expansion of concrete. Consequently, the concrete structure may be damage .The effects of total and total effective sulfate contents on high strength concrete (HSC) have been studied in the present study. The research studied the effect of sulfate content in cement , sand and gravel , as well as comparing the total sulfate content with the total effective SO3 content. Materials used were divided into two groups of SO3 in cement ,three groups of SO3 in sand ,and two groups of SO3 in gravel. The results show that considering the total effective sulfate con

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Publication Date
Sun Apr 30 2017
Journal Name
Journal Of Engineering
Influence of Internal Sulfate Attack on Some Properties of Self Compacted Concrete
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      Self-compacted concrete (SCC) is a highly flowable concrete, with no segregation which can be spread into place by filling the structures framework and permeate the reinforcement without any compaction or mechanical consolidation ACI 237R-14. One of the most important problems faced by concrete industry in Iraq and Gulf Arab land is deterioration due to internal sulfate attack (ISA) that causes damage of concrete and consequently reduces its compressive strength, increases expansion and may lead to its cracking and destruction. The experimental program was focused to study two ordinary Portland cements with different chemical composition with (5, 10 and 15) % percentage of high reactivity metakaoline (HRM)

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Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Theoretical and experimental studies for different compounds to calculate: electronic transfer, energy gap and NLO properties
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This work involves theoretical and experimental studies for seven compounds to calculate the electrons spectrum and NLO properties. The theoretical study is done by employing the Time Depending Density Functional Theory TD-DFT and B3LYP/high basis set 6-311++G (2d,2p), using Gaussian program 09. Experimental study by UV/VIS spectrophotometer device to prove the theoretical study. Theoretical and experimental results were applicable in spectrum and energy gap values, in addition to convergence theoretically the energy gap results from ΔEHOMO-LUMO and UV/VIS. spectrum. Consider the theoretical method very appropriate to compounds that absorb in vacuum UV.

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Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
The objective Effect of Internal and External Environment and its Psychological & Practical Reflection on the Political Decision-Making Process
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The objective Effect of Internal and External Environment and its Psychological & Practical Reflection on the Political Decision-Making Process

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