The enhancement of the thermal and thermo-hydraulic performance of a semi-circular solar air collector (SCSAC) is numerically investigated using porous semi-circular obstacles made of metal foam with and without longitudinal porous Y-shaped fins. Two 10 and 40 PPI porous material samples are examined. Three-dimensional models are built to simulate the performance of SCSAC: model (I) with clear air passage; model (II) with only metal foam obstacles, and model (III) with metal foam obstacles as well as porous Y-fins. COMSOL Multiphysics software version 6.2 based on finite element methodology is employed. A conjugate heat transfer with a (k-ε) turbulence model is selected to simulate both heat transfer and fluid flow across the entire computational domain. However, only the local thermal non-equilibrium (LTNE) model of heat transfer is applied in the porous regions. The findings demonstrated that adding metal foam as the novel proposed configuration particularity of model (III) may enhance the thermal efficiency by about 30%, and the outlet air temperature may rise to 7% compared to other models. Also, the performance evaluation factor of this model is greater than one in all cases. Additionally, the thermal enhancement is accomplished by occupying only 5% of the air passage volume, thereby including an associated pressure drop of minimal magnitude.
From different hospitals in Baghdad city, 25 clinical isolates of Proteus spp. were collected from different clinical samples, all isolates were identified as Proteus mirabilis by using bacteriological and biochemical assays in addition to Vitek-2 identification system. 15 (60%) isolates were identifying as Proteus mirabilis. The susceptibility of P. mirabilis isolates towards cefotaxime and ceftazidime was (66.6 %), (20%) consecutively; while extended spectrum β-lactamases producing P. mirabilis percentage was (30.7 %). Because blaVEB-1 was documented as an important indicator for increasing risk of extended spectrum beta ßlactamases producing P. mirabilis isolates that began to spread from many geographic area to Far east which inc
... Show MoreBackground: Bone augmentation techniques are commonly employed in medical fields. This biomaterial system must be readily available, easily applicable by minimally-invasive technique and able to release an osteoinductive growth factor. Such a system will be able to engineer new bone formation locally at the site of injection. Hyaluronic acid has osteogenic potential that can be exploited not only for repairing bone defects but also for providing transplantable bone for the reconstruction of a variety of bone defects. The aims of this study were to evaluate the effects of Hyaluronic acid gel on bone healing by immunohistochemical estimation of transforming growth factor -beta 3 in experimental and control groups. Materials and methods: Thirt
... Show MoreBackground: Simultaneous and staged guided bone regeneration (GBR) is one of the several surgical techniques that have been developed in the past two decades to regenerate bone and thus to allow implant placement in compromised sites (fenestration and dehiscence). It is a surgical procedure that consists of the placement of a cell-occlusive physical barrier between the connective tissue and the alveolar bone defect. The treatment concept advocates that regeneration of osseous defects is predictably attainable via the application of occlusive membranes, which mechanically exclude non-osteogenic cell populations from the surrounding soft tissues, thereby allowing osteogenic cell populations originating from the parent bone to inhabi
... Show MoreStudents' passive listening to their teacher's reading is one of main
reasons behindtheir weakness in the reading skill which in its turn may
hinderachieving the in desired objectives.
When exploiting critical thinking, which will lead to deeper
understanding of the intellectual content, in learning and accurate and
correct students' outcomes.
Active listening allows paying attention to the speaker, asking him,
arguing with him, judging what he says, and making decision on what
he says. For this reason, the researcher felt the need for preforming a
study to identify the effect of critical listening on developing students'
critical thinking at reading in the Kurdish language department.
The researcher has
In light of the increasing interest in Child-rearing in nurseries and kindergartens and the most important experiences gained by the child at this stage that form the basis for the subsequent stages of her/his physical mental and social growth.
The significance of the research concentrates the need to asses the affecting variables on the child growth to create opportunities for her/him to have intact rearing.
The research also aims to classify these variables at each age level and highlight its moral role.
The problem of the research is the lack of clarity of different variables impact of the child growth in different age levels in nurseries and kindergart
... Show MoreAbstract
In this study, the effect of carboxylic methyl cellulose (CMC), and sodium dodcyl benzene sulfonate (SDBS) as an aqueous solution on the drag reduction was investigated. Different concentrations of (CMC) and (SDBS) such as (50, 100, 150, 200, 250, 300, 350, 400, 450, and 500 ppm) were used to analyze the aqueous solution properties, including surface tension, conductivity, and shear viscosity. The optimum four concentrations (i.e., 50, 100, 200, and 300 ppm) of fluid properties were utilized to find their effect on the drag reduction. Two different PVC pipe diameters (i.e., 1" and 3/4") were used in this work. The results showed that blending CMC with SDBS gives
... Show MoreThe need for detection and investigation of the causes of pollution of the marshes and submit a statistical study evaluated accurately and submitted to the competent authorities and to achieve this goal was used to analyze the factorial analysis and then obtained the results from this analysis from a sample selected from marsh water pollutants which they were: (Electrical Conductivity: EC, Power of Hydrogen: PH, Temperature: T, Turbidity: TU, Total Dissolved Solids: TDS, Dissolved Oxygen: DO). The size of sample (44) sites has been withdrawn and examined in the laboratories of the Iraqi Ministry of Environment. By illustrating SPSS program) the results had been obtained. The most important recommendation was to increase the pumping of addit
... Show MoreWeibull distribution is considered as one of the most widely distribution applied in real life, Its similar to normal distribution in the way of applications, it's also considered as one of the distributions that can applied in many fields such as industrial engineering to represent replaced and manufacturing time ,weather forecasting, and other scientific uses in reliability studies and survival function in medical and communication engineering fields.
In this paper, The scale parameter has been estimated for weibull distribution using Bayesian method based on Jeffery prior information as a first method , then enhanced by improving Jeffery prior information and then used as a se
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