An experimental and numerical study has been carried out to investigate the heat transfer by natural convection and radiation in a two dimensional annulus enclosure filled with porous media (glass beads) between two horizontal concentric cylinders. The outer cylinders are of (100, 82 and70mm) outside diameters and the inner cylinder of 27 mm outside diameter with (or without) annular fins attached to it. Under steady state condition; the inner cylinder surface is maintained at a high temperature by applying a uniform heat flux and the outer cylinder surface at a low temperature inside a freezer. The experiments were carried out for an annulus filled with
glass beads at a range of modified Rayleigh number (4.9 ≤ Ra≤ 69), radiation
The subject of children's rights in the modern era of the priorities of educators , because the child in the community is the future , which is held by the hope which is the basis for society in the renaissance and progress so quickly communities to prove these rights through its various institutions and issued legislation and held numerous conferences and taking specialists the field of childhood Aatron aspects of this rights and Aasalunha including a benefit for children until tomorrow for the rights of children , psychological and social health and educational . Therefore, the current study focused on the awareness of parents and educators of children's rights as individuals most closely satisfying their needs and rights. The
... Show MoretA novel synthesis procedure is presented for preparing triethanolamine-treated graphene nanoplatelets(TEA-GNPs) with different specific areas (SSAs). Using ultrasonication, the covalently functionalizedTEA-GNPs with different weight concentrations and SSAs were dispersed in distilled water to prepareTEA-GNPs nanofluids. A simple direct coupling of GNPs with TEA molecules is implemented to synthesizestable water-based nanofluids. The effectiveness of the functionalization procedure was validated by thecharacterization and morphology tests, i.e., FTIR, Raman spectroscopy, EDS, and TEM. Thermal conduc-tivity, dispersion stability, and rheological properties were investigated. Using UV–vis spectrometer, ahighest dispersion stability of 0.876
... Show MoreThis study conducted an analytical investigation on the behavior of concrete beams with openings reinforced by glass-fiber-reinforced polymer (GFRP) bars. In this study, five proposed beams reinforced by GFRP bars as flexural and shear reinforcement with openings were numerically examined. The variables were the opening orientation (vertical and horizontal) and the number of openings. These openings were located within the flexural zone of the proposed beams. The result shows that the vertical openings had a significant effect over the horizontal openings on reducing the ultimate load and increasing the mid-span deflection compared with the control beam. Moreover, the results showed t
This paper presents an experimental and theoretical analysis to investigate the two-phase flow boiling heat transfer coefficient and pressure drop of the refrigerant R-134a in the evaporator test section of the refrigeration system under different operating conditions. The test conditions considered are, for heat flux (13.7-36.6) kW/m2, mass flux (52-105) kg/m2.s, vapor quality (0.2-1) and saturation temperature (-15 to -3.7) ˚C. Experiments were carried out using a test rig for a 310W capacity refrigeration system, which is designed and constructed in the current work. Investigating of the experimental results has revealed that, the enhancement in local heat trans
... Show MoreThis work deals with the effect of adding aluminum nanoparticles on the mechanical properties, micro-hardness and porosity of memory-shape alloys (Cu-Al-Ni). These alloys have wide applications in various industrial fields such as (high damping compounds and self-lubricating applications). The samples are manufactured using the powder metallurgy method, which involved pressing in only one direction and sintered in a furnace surrounded by an inert gas. Four percentages (0%, 5%, 10%, and 15%) of aluminum nanoparticles were fabricated, which depended on the weight of aluminum powder (13%) in the sample under study. To find out which phase is responsible for the reliability of the formation of this type of alloy and its porosity, X-ray diffr
... Show MoreThe research aims to identify the level of awareness of student teachers in the behavioral disorders and autism specialization about the diagnosing Autism Spectrum Disorder and Social (Pragmatic) Communication Disorder according to some variables. The study was conducted on a sample of (113) student teachers. The researcher employed the awareness scale of a teacher-screening questionnaire for autism spectrum disorder and social pragmatic communication disorder. The results showed that the average of teachers in the total degree of awareness of autism spectrum disorder and social communication have recorded a moderate degree. As for the awareness of autism spectrum disorder was high. Then, the awareness of social communication disorder wa
... Show MoreBackground: The COVID-19 virus outbreak had a massive effect on many parts of people's lives, as they were advised to quarantine and lockdown to prevent the virus from spreading, which had a big impact on people's mental health, anxiety, and stress. Many internal and external factors lead to stress. This negatively influences the body's homeostasis. As a result, stress may affect the body's capacity to use energy to defend against pathogens. Many recent investigations have found substantial links between human mental stress and the production of hormones, prohormones, and/or immunological chemicals. some of these researches have verified the link between stress and salivary cortisol levels. The aim of this study is to measure salivary corti
... Show MoreIt is important to note that Posaconazole (POCZ) is a newly developed extended-spectrum triazole that belongs to BCS class II and has a solubility of less than 1µg/ml. In patients with a weakened immune system, POCZ has been shown to be effective as an antifungal treatment for invasive infections caused by candida and aspergillus species. The nano-micelles technique can be used to increase POCZ solubility. In order to increase their apparent solubility in water, nano-micelles are made by combining macromolecules that self-assemble into ordered structures capable of entrapping hydrophobic drug molecules in the interior domain. Dispersed colloidal systems, of which nano-micelles are a subset, are a large and diverse group. Composed of a p
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