The rate of gas induction was measured in gas-inducing type mechanically agitated contactors provided with two impellers. A reactor of 0.5 m i.d. was used with a working capacity of 60 liters of liquid. Tap water was used as the liquid phase, and air was used as the gas phase. The bioreactor mixing system consists of two equal diameter stirrers; the top impeller is shrouded-disk/curved-blade turbine with six evacuated bending blades, while the bottom impeller was disk turbine. The impeller speed was varied in the range of 50 to 800 rpm. The ratio of impeller diameter to tank diameter (D/T) and the submergence (S) of upper impeller from the top were varied. The effects of clearance of lower impeller from the tank bottom (C2) and the impeller spacing (C3, distance between the two impellers) were also varied over a wide range. Rate of gas induction (Q) was measured for all these combinations. It was found that the rate of gas induction increases with both decreasing in submergence and increasing in the stirrer diameter. While it decreases with both increasing the impeller spacing and the clearance from the bottom.
This study aims to show the level of organizational fairness at Hawija Technical Institute ,from the point view of the faculty ,and the degree of their performance, and the nature of the relationship between organizational fairness and their performance.
The researchers accomplish and develop a questionnaire on Likert a three - dimensional scale to de applied on a samp
... Show MoreAS Salman, SK Hameed…, Karbala Journal of Physical Education Sciences, 2020
Background This study aimed to develop remineralizing calcium-phosphate (CaP) etchant pastes for enamel conditioning before bracket bonding and evaluate the bonding performance, failure pattern, and enamel surface integrity post bracket debonding in comparison with the conventional phosphoric acid (PA) etchant gel. Material and Methods Micro-sized monocalcium phosphate monohydrate and hydroxyapatite (micro- and nano-sized) powders were mixed with various phosphoric and nitric acid concentrations to develop eight acidic CaP pastes. Ninety extracted human premolars were randomly assigned into eight experimental and one control group (n=10). The developed pastes and control (commercial 37% PA-gel) were applied onto the enamel using the etch-a
... Show MoreIn this research an experimental study has done for testing the thermal performance of selective surfaces used in solar collectors for substrate of iron, galvanized iron and aluminum which are commercially available. The coating process for the samples has done in two ways, the electroplating and the chemical spray pyrolysis. The results of the thermal performance test of these samples are comparing with the thermal performance of a sample without paint and other paint with black paint without shines commercially available. For the electroplated samples, the performance study has done for different immersion time in plating bath, the
distance between electrical poles, the current density, and area ratio of the sample plated area to
Fencing is characterized by rapid and sudden changes that require speed in decision-making and motor responses. In addition, it requires high sensorimotor awareness and strong coordination between leg, arm, and eye movements. In the current study, the researchers used cognitive coordination response speed exercises and physical and skill exercises in order to develop performance in the time counterattack. The aim of the study is to identify the effect of cognitive coordination response speed exercises on the performance of the time counterattack of female foil fencers. An experimental method was used on the female fencing team players at the College of Physical Education and Sports Sciences for Women/University of Baghdad in the spo
... Show MoreIn this research work, a simulator with time-domain visualizers and configurable parameters using a continuous time simulation approach with Matlab R2019a is presented for modeling and investigating the performance of optical fiber and free-space quantum channels as a part of a generic quantum key distribution system simulator. The modeled optical fiber quantum channel is characterized with a maximum allowable distance of 150 km with 0.2 dB/km at =1550nm. While, at =900nm and =830nm the attenuation values are 2 dB/km and 3 dB/km respectively. The modeled free space quantum channel is characterized at 0.1 dB/km at =860 nm with maximum allowable distance of 150 km also. The simulator was investigated in terms of the execution of the BB84 prot
... Show MoreThe current study monitors the mechanisms of formation of the actor's performance expressive system (voice and motion) and the levels of their construction consistent with the aesthetic premise of the theatrical performance through incorporating what is natural, materialistic (physiological) and artistic and philosophical virtual (aesthetic ), through which the creative actor seeks not to repeat the image and substance of a thing according to its natural life image, in favor of new aesthetic reproduction governed by a group of significant relationships formed according to (artistic and philosophical) characteristics and features that distinguish the artistic accomplishment from its reality(its natural and functional reference). According
... Show MoreIn this research work, a simulator with time-domain visualizers and configurable parameters using a continuous time simulation approach with Matlab R2019a is presented for modeling and investigating the performance of optical fiber and free-space quantum channels as a part of a generic quantum key distribution system simulator. The modeled optical fiber quantum channel is characterized with a maximum allowable distance of 150 km with 0.2 dB/km at =1550nm. While, at =900nm and =830nm the attenuation values are 2 dB/km and 3 dB/km respectively. The modeled free space quantum channel is characterized at 0.1 dB/km at =860 nm with maximum allowable distance of 150 km also. The simulator was investigated in terms of the execution of the BB84 p
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