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.
مشكلة البحث
لقد حدا بالمهتمين في الميدان التربوي، والادارة التربوية بصورة خاصة، ان يجدوا علاقات ايجابية بين متغيرات الميدان التربوي عامة والاداري بصورة خاصة وقد تمخض هذا عن وجود علاقة ايجابية بين اداء المديرين ورؤساء الاقسام ودرجة التقويم، ومن هنا يتضح انه كلما كان التقويم عالياً في درجته، يتضح ان هناك اداءً فاعلاً ولكن ليس بالشكل الحقيقي لمعنى التقويم ما لم يكن هناك
... Show More٠ اش١جخ ٗزفقث ٌٟبِ ٟجعبؾٌّا تٔبغٌا ٟف بقزخِ ٟئبنل ( ًئاضل بساحم ) توهم ىلع ءىضلا طٍلسحو بلارم ءادأ ىلع اهرٍثأحو تٍوهملا اهحاءارجإو تمذخخسملا اهحاٍومح ثٍح نم تٍئاضملا تبساحملا دبثبغؾٌا . اسبِٙٚ د ءبمٌلأ ٟمبٌّا ـؾف ٍٝػ ض١وشزٌا يلاخ ِٓ خ١ٔٛٔبمٌا سِٛلأبث خفشؼٌّا ءٛم ٟف دب٠شؾزٌا ًجمزغٌّا ٍٝػ حشظٔ ٌا خجعبؾٌّا ْا شؽبجٌا ظزٕزعاٚ ذٍجٌٍ ٞدبقزللاا َذمزٌا خٍغػ غفد ٟف ُٙغر خ١ئبنم ، خجعبؾٌّا ٟف خِذخزغٌّا خض٠ذؾٌا ت١ٌ
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The impact of management control systems (MCS) on organizations performance empirical research has been the subject of numerous studies during the past decade in developed and emerging economies. In the contemporary competitive, complex and changing global business environment, firms are being challenged to adopt business models that enable them to address the strategic uncertainties and risks they face in their business environments. The main issue of this study is that management accounting researchers argue that one of the ways firms can continually rejuvenate themselves to survive and succeed in these complex and uncertain environments is to understand the role of management control systems in Formulating a b
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Developments are carried out to enhance the performance of vertical axis wind turbines (VAWT). This paper studies the performance of the ducted wind turbine with convergent duct (DAWT). Basically, the duct technique is utilized to provide the desired wind velocity facing the turbine. Methodology was developed to estimate the decisive performance parameter and to present the effect of the convergent duct with different inlet angles. The ducted wind turbine was analyzed and simulated using MATLAB software and numerically using ANSYS-Fluent 17.2. Result of both approaches were presented and showed good closeness for the two cases of covering angles 12 and 20 respectively. Results also showed that the convergent duct with an inlet angl
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A novel demountable shear connector is proposed to link a concrete slab to steel sections in a way that resulting steel-concrete composite floor is demountable, i.e. it can be easily dismantled at the end of its service life. The proposed connectors consist of two parts: the first part is a hollow steel tube with internal threads at its lower end. The second part is a compatible partially threaded bolted stud. After linking the stud to the steel section, the hollow steel tube can be fastened over the threaded stud, which create a complete demountable shear connector. The connector is suitable for use in both composite bridges and buildings, and using cast in-situ slabs, precast solid slabs, or hollow-core precast slabs. A series of push-off
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Translating culture-specific proverbs (CSPs) is a challenging task since they often occur in a peculiar context. Further, CSPs are intended to imply meanings that extend far beyond the literal meaning of such a kind of proverbs. As far as English and Arabic are concerned, translators often encounter problems in translating CSPs due to cultural differences between the source language(SL) and the target language (TL) as well as what seems to be the lack of equivalence for some CSPs.
In view of this, the present study aims at investigating the translation of CSPs in three English-Arabic dictionaries of proverbs, namely Dictionary of Common English Proverbs Translated and Explained (2004), One thousand and One English Pr
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The ability to inhibit corrosion of low carbon steel in a salt solution (3.5%NaCl) has been checked with three real expired drugs (Cloxacillin, Amoxicillin, Ceflaxin) with variable concentrations (0, 250, 500, 750) mg/L were examined in the weight loss. The inhibition efficiency of the Cloxacillin 750 mg/L showed the highest value (82.8125 %) and the best inhibitor of the rest of the antibiotics. The different concentrations of Cloxacillin drug (0, 250, 500, 750) mg/L and temperature (25, 35, 45, 55) oC were studied as variables with potentiodynamic polarization, Scanning Electron Microscopy (SEM) for surface morphology and electrochemical impedance spectroscopy (EIS) depending on current values and the resistance of charge to
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