Experimental and numerical investigations of the centrifugal pump performance at non-cavitating and cavitating flow conditions were carried out in the present study. Experiments were performed by applying a vacuum to a closed-loop system to investigate the effects of the net positive suction head available (NPSHa), flow rate, water temperature and pump speed on the centrifugal pump performance. Accordingly, many of the important parameters concerning cavitation phenomenon were calculated. Also, the noise which is accompanied by cavitation was measured. Numerical analysis was implemented for two phase flow (the water and its vapor) using a 2-D simulation by ANSYS FLUENT software to investigate the internal flow of centrifugal pump under cavitating conditions. It was observed that with decreasing NPSHa, the values of the pump head, flow rate and efficiency initially remain constant, but with further reduction in NPSHa these parameters will decrease. Also, it was found that at 3% head drop the percentage drop of the flow rate is less than 2% whereas the percentage drop of the efficiency is greater than 3%. Numerically, it was noticed that the cavitation regions appear at the leading edge of suction side of the impeller blades which represents the lowest pressure area inside the computational domain of the centrifugal pump.
Abstract
Nephrotoxicity is defined as rapid deterioration in kidney functions. It arises from direct exposure to drugs or their metabolites. Methotrexate is a famous chemotherapeutic drug with anti-inflammatory and immunosuppressive properties. A high-dose methotrexate-induced renal dysfunction can be life threatening. Cyanocobalamin, one of the forms of vitamin B12, acts as a coenzyme in the conversion of homocysteine to methionine in the cytosol, and the conversion of methylmalonyl-CoA to succinyl-CoA in the mitochondrion. This study is designed to examine the effect of cyanocobalamin in two different doses each co-administered with methotrexate at 20 mg/kg induced nephrotoxicity in rat
... Show MoreBackground: As acetaminophen (APAP) toxicity has become more common in many countries, related cases of poisoning, whether deliberate or unintentional, have been identified as a key contributor to acute liver failure. Aime: To discover if omega-369 fatty acids could protect the liver of male mice from the effects of acetamiophen. Methods: Thirty-five albino male mice were allocated to one of five groups at random. Group 1 served as the "negative control" and received a single intraperitoneal injection (10 ml/kg) of normal saline on the eleventh day of the test following ten days of receiving liquid paraffin orally at a dose of 10 ml/kg. The liquid paraffin was given to group 2 "positive control". Group 3 received Omega 369 (50 mg/kg
... Show MoreThis study aimed to see how allicin (45mg/kg BW) affected diabetic Mellitus in male rats (DM). Forty male rats were utilized, and they were split into four groups at random for 42 days. T2 was treated with 45 mg/kg B.W of allicin dissolved in 1 ml of D.W daily and injected with a single dose of sodium citrate buffer (0.5ml Intra-Peritoneal IP), DM was induced in T1 and T2 by injection of a single dose of streptozotocin 50 mg/kg B.W IP, T1 was assigned as a positive control, T3 received 45 mg/kg B.W. of allicin dissolved in 1 ml D.W. every day, and a single dose of sodium citrate buffer was injected (0.5ml IP). When diabetic rats treated with allicin in T2 were compared to diabetic rats in T1, the findings indicated a significant increase (P
... Show MoreBackground: Gugglusterone has been reported to provide protection against inflammatory and oxidative reactions of different pathological conditions. Objectives: The main object of this research work is to evaluate the renoprotective effects of guggulsterone in the prevention of cisplatin-induced nephrotoxicity in rats via assessment of renal function and histological study. Materials and methods: Rats in this study were split into four groups which comprise a control group, an induction group, a third group receiving low-dose guggulsterone, and a fourth group receiving high-dose guggulsterone. Results: a single dose of cisplatin drug has jeopardisedrenal physiology that has been demonstrated in histopathology sections and elevation
... Show MoreThe liver protective effects of pentoxifylline were studied through pre-treatment of rats with various intraperitoneal (IP) doses (25, 50 and 100mg/kg/day) 14 days before induction of liver toxicity by carbon tetrachloride (CCl4). The parameters of oxidative stress, malondialdehyde (MDA) and reduced glutathione (GSH) were measured in liver homogenate in addition to histopathological examinations. Analysis of data revealed significant amelioration of oxidative stress in groups of animals pre-treated with different doses of pentoxifylline (PTX) compared to group of animals intoxicated by CCl4 as evidenced by lowering MDA contents and elevation of GSH levels in liver tissue homogenate but the levels still signifi
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The Ash'aris and their position on faith, An Ideological Study
Omed AbdulQader rasool
College of Islamic Sciences/Salahaddin University-Erbil
Abstract
The concept of faith is very complex, and there are a lot of talk about it among the major Islamic groups such as the Kharijites, the Mu'tazila, the Jahmiyya and others, because of its great importance, and the worldly and eschatological effects it entails according to the elements of faith such as recognition, ratification and action.
The researcher chose one sect, which is the
... Show MoreSeveral recent approaches focused on the developing of traditional systems to measure the costs to meet the new environmental requirements, including Attributes Based Costing (ABCII). It is method of accounting is based on measuring the costs according to the Attributes that the product is designed on this basis and according to achievement levels of all the Attribute of the product attributes. This research provides the knowledge foundations of this approach and its role in the market-oriented compared to the Activity based costing as shown in steps to be followed to apply for this Approach. The research problem in the attempt to reach the most accurate Approach in the measurement of the cost of products from th
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