This paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the solidification time is inversely proportional to the fin's length. The heat release rate for the case with the longest fins (stem length of 10 mm) is 39 W, almost 2.8 times higher than that with the fins' stem length of 5 mm. The case with the tributary's angle of 22.5o solidified in 55 min, faster than the other studied angles. Increasing the number of fins significantly affects the solidification time and discharging rate. By increasing the number of fins from 3 to 9, the heat transfer rate improves by 194%. The advantages of circular Y-shaped fins are well known in heat transfer applications and therefore are characterized toward higher performance in this study for the first time during the solidification process.
The 17 α-ethinylestradiol (EE2) adsorption from aqueous solution was examined using a novel adsorbent made from rice husk powder coated with CuO nanoparticles (CRH). Advanced analyses of FTIR, XRD, SEM, and EDSwere used to identify the classification parameters of a CRH-like surface morphology, configuration, and functional groups. The rice husk was coated with CuO nanoparticles, allowing it to create large surface area materials with significantly improved textural qualities with regard to functional use and adsorption performance, according to a detailed characterization of the synthesized materials. The adsorption process was applied successfully with elimination effectiveness of 100% which can be kept up to 61.3%. The parameters of ads
... Show MoreSystemic lupus Erythematosus is an autoimmune disease of unknown aetiology affecting multiple organ system. Reactive nitrogen and oxygen species are claimed to play a role in this disease. However, the potential of Nitrosative/Oxidative Stress to elicit an autoimmune, response remain till now largely unexplored in humans. This study was done to investigate the status and contribution of nitrosative/oxidative stress in Iraqi patients for systemic lupus erythematosus. Blood samples from 19 patients with systemic lupus erythematosus and 19 age-and sex- matched apparently healthy controls were evaluated for serum levels of nitrosative/oxidative stress markers including nitric oxide, peroxynitrite and malondialdehyde. Nitric oxide levels were
... Show More4 Blood Res 2018;53:314-319. Received on August 11, 2018 Revised on August 30, 2018 Accepted on August 30, 2018 Background Iron overload is a risk factor affecting all patients with thalassemia intermedia (TI). We aimed to determine whether there is a relationship of serum ferritin (SF) and alanine ami- notransferase (ALT) with liver iron concentration (LIC) determined by R2 magnetic reso- nance imaging (R2-MRI), to estimate the most relevant degree of iron overload and best time to chelate in patients with TI. Methods In this cross-sectional study, 119 patients with TI (mean age years) were randomly se- lected and compared with 120 patients who had a diagnosis of thalassemia major (TM). Correlations of LIC, as determined by R2-MRI, with SF
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Abstract
The use of modern scientific methods and techniques, is considered important topics to solve many of the problems which face some sector, including industrial, service and health. The researcher always intends to use modern methods characterized by accuracy, clarity and speed to reach the optimal solution and be easy at the same time in terms of understanding and application.
the research presented this comparison between the two methods of solution for linear fractional programming models which are linear transformation for Charnas & Cooper , and denominator function restriction method through applied on the oil heaters and gas cookers plant , where the show after reac
... Show MoreNew series of metal ions complexes have been prepared from the new ligand [4-Amino-N-(5-methyl-isaxazol-3-yl)-benzenesulfonamide] derived from Sulfamethoxazole and 3-aminophenol. Accordingly, mono-nuclear Mn(II), Fe(III), Co (II), and Rh(III) complexes were prepared by the reaction of previous ligand with MnCl2.4H2O, CoCl2.6H2O, FeCl3.6H2O and RhCl3H2O, respectively. The compounds have been characterized by Fourier-transform infrared (FTIR), ultraviolet–visible (UV–vis), mass, 1H-, and 13C-nuclear magnetic resonance (NMR) spectra and thermo gravimetric analysis (TGA& DSC) curve, Bohr magnetic (B.M.), elemental microanal
... Show MoreThis search includes the preparation of Schiff base ligand (SB) from condensation primary amine with vanillin. The new ligand was diagnosed by spectroscopic methods as Mass, NMR, CHN and FTIR. Ligand complexes were mixed from new (SB) and Anthranillic acid (A) with five metal (II) chlorides. The preparation and diagnosis were conducted by FTIR, CHN, UV-visible, molar conductivity, atomic absorption and magnetic moment. The octahedral geometrical shape of the complexes was proposed. The ligands and their new complexes were screened with two different types of bacteria.
The wastewater arising from pulp and paper mills is highly polluted and has to be treated before discharged into rivers. Coagulation-flocculation process using natural polymers has grown rapidly in wastewater treatment. In this work, the performance of alum and Polyaluminum Chloride (PACl) when used alone and when coupled with Fenugreek mucilage on the treatment of pulp and paper mill wastewater were studied. The experiments were carried out in jar tests with alum, PACl and Fenugreek mucilage dosages range of 50-2000 mg/L, rapid mixing at 200 rpm for 2 min, followed by slow mixing at 40 rpm for 15 min and settling time of 30 min. The effectiveness of Fenugreek mucilage was measured by the reduction of turbidity and Chemical Oxygen Demand
... Show MoreRegular sampling for six months from January to July 2012 were taken in small, shallow, perennial, standing ponds near the Greater Zab River, Gwer district, Erbil. A variety of physicochemical parameters were determined. Air and water temperature were falling between 15.2 - 34.7 ? C and 15.5 and 26.5 ?C. The waters are neutral (pH 7.38-8.27), hard, alkaline, salty, high in TDS and EC (892-966?S/cm, and rich in nutrients (NO3: 2.1-4.1mg/l, PO4: 0.33-0.62 mg / l , SO4: 24.7-80.2 mg / l ). The attention fixed on a filamentous blue- green algae Glaucospira Lagerheim, 1982) which is new to Iraqi flora. It is a filament (trichome), solitary, pale or yellowish blue – green, without sheath, Screw like coiled, motile, some of them are activ
... Show Moreتعد الرماية واحدة من الألعاب التي يقاس مستوى الانجاز فيها بالأرقام إذ ارتفعت الأرقام المسجلة بالنسبة لسلاح المسدس الهوائي حتى وصلت عند بعض الأبطال العالميين إلى الانجاز النهائي ، وقد لجأ المدربون إلى مختلف الطرق التدريبية, وان ضعف الثبات والتركيز هما اللذان يقودان إلى هبوط مستوى الانجاز في الرماية ، ولتحقيق التركيز والثبات المطلوبين أثناء الرمي يجب التدريب على مطاولة حمل السلاح التي تعد من أصعب تدريبات الر
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