The ejector refrigeration system is a desirable choice to reduce energy consumption. A Computational Fluid Dynamics CFD simulation using the ANSYS package was performed to investigate the flow inside the ejector and determine the performance of a small-scale steam ejector. The experimental results showed that at the nozzle throat diameter of 2.6 mm and the evaporator temperature of 10oC, increasing boiler temperature from 110oC to 140oC decreases the entrainment ratio by 66.25%. At the boiler temperature of 120oC, increasing the evaporator temperature from 7.5 to 15 oC increases the entrainment ratio by 65.57%. While at the boiler temperature of 120oC and
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The six Arab Gulf states (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, UAE) play a vital role, especially with its geographical location and natural resources (oil and gas) as well as other cultural and civilizational elements, in achieving global economic balance and more specifically global energy security, naturally because of these countries have a comparative advantage in the field of fossil energy (oil and gas), thus this sector becomes more attractive for local and international investments alike. Being the energy sector a leader sector in the economic development process, and the basic factor to achieve savings and financial surpluses in thes
... Show MoreBanks face different types of banking risks that limit the performance of its functions and achieve its objectives, including the financial risk that is based on current research into two types including a credit and liquidity risks. And established credit risk due to the possibility of delaying the borrowers to fulfill their obligations to the bank when due or non-payments on according to the terms agreed upon, while liquidity risk arises as a result of the inability of the bank to fund the financial needs, any inability to provide cash to pay its obligations short on credit without achieving tangible loss or the inability to employ the funds properly and show the liquidity risk in the event of inadequate cash inflows to the bank for an
... Show MoreGenistein (GEN) is The major isoflavone found in soybeans, has a number of cardiovascular health benefits, Postmenopausal syndrome and osteoporosis. A direct flow injection analysis method for estimation of (GEN) in pure and supplements formulation . This system is based on diazotization coupling reactions between procaine penciline (PR) and genistein in basic medium, they formed yellow dyes have maximum absorption at 416 nm. Calibration curve were constructed over different GEN concentrations, linearity for GEN was 10-100 µg.mL-1 and detection limits of 1.51 ?g/mL. In the FIA technique, all analytical factors were analyzed and optimized. The established method was successfully used to determine GEN in the formulations of its supplement
... Show MoreA new approach and the developed FIA technique with many advantages (economic, fast, simple, accurate, and high throughput) are used to determine the decongestant drugs (Phenylephrine.HCl, Oxymetazoline.HCl) in biological samples, pharmaceutical formulations, and pure samples via continuous flow injection technique by oxidative coupling reaction, where the method depends on the interaction of the decongestant drug with organic reagents to produce colored compounds, where Phenylephrine reacts with 4-AAP at λmax503 nm to produce a red compound, and the Beer’s law range of 10-600 μg.mL-1 . As for Oxymetazoline, it reacts with DNPH at λmax 631nm to produce a green compound with a linear dynamic range of
... Show MoreSimple and sensitive batch and flow injection methods (normal and reverse flow injection analysis (nFIA and rFIA)) for spectrophotometric determination of vancomycin hydrochloride (VHC) in pharmaceutical preparations were proposed and optimized. Both methods are based on the oxidative - coupling reaction between vancomycin hydrochloride and 2,4-Dinitrophenylhydrazine (DNPH) in the presence of sodium periodate in alkaline medium to form a yellow water-soluble product that is stable and has a maximum absorption at 461 nm. Beer’s law was obeyed over the range of 1- 40, 0.5-120 and 0.5-150 μg.mL-1; the limits of detection were 0.537, 0.0823 and 0.233 μg.mL-1 for batch, normal and reverse flow injection methods respectively. The sampling
... Show MoreThe results of research to reach the conditions that prevents the emergence of primary or secondary voids and achieve worker benefit from molded by almost 100%, which was the situation that cast poured in a mold heated and insulated from all sides to achieve freezing directional full starting from the region remote from the casting and ending then. Has also been compared to the microscopic structure of the resulting castings of various molding conditions, as these conditions have achieved the best sound microscopic structures.
This paper presents the results of experimental investigation carried out on concrete model piles to study the behaviour of defective piles. This was achieved by employing non-destructive tests using ultrasonic waves. It was found that the reduction in pile stiffness factor is found to be about (26%) when the defect ratio increased from (5%) to (15%). The modulus of elasticity reduction factor as well as the dynamic modulus of elasticity reduction factor increase with the defect ratio