An experimental and numerical study was carried out to investigate the heat transfer by natural convection in a three dimensional annulus enclosure filled with porous media (silica sand) between two inclined concentric cylinders with (and without) annular fins attached to the inner cylinder under steady state condition. The experiments were carried out for a range of modified Rayleigh number (0.2 ≤Ra*≤ 11) and extended to Ra*=500 for numerical study and for annulus inclination angle of (δ = 0˚, 30˚, 60˚ and 90˚). The numerical study was to give the governing equation under assumptions that used Darcy law and Boussinesq’s approximation and then it was solved numerically using finite difference approximation. It was found that the average Nusselt number depends on (Ra*, Hf, δ and Rr ). The results showed that the increasing of the fin length increases the heat transfer rate for any fin pitch unless the area of the inner cylinder exceeds that of the outer one; then the heat will be stored in the porous media. A comparison was made between the results of the present work and those of other researches for the case without fins and excellent agreement was obtained.
Context: The ability of implant dentistry to be a successful alternative for edentulous patients has increased in the last decade. Clinical features such as osseointegration and stability, in addition to the endurance of the integration urged the researchers towards a better understanding of the design parameters that control long term success of the implants. It is therefore necessary to quantify the effect of changing implant design parameters on interface stress distribution within the maxilla bone. Methods and Materials: A 3D-finite element study was conducted to investigate the effect of changing implant shape parameters (implant body design and implant thread depth) on stress distribution while insertion of the implant in two diff
... Show MoreWater supply networks are marred by serious risks of imperceptible pipeline leakage, posing sustainability and performance threats. This article highlights the use of vibratory signal features to get around the drawbacks of traditional methods in a highly detailed framework for leak detection based on CatBoost. demonstrated excellent diagnostic performance and carried out a thorough test performance evaluation on five leakage configurations . The expected system achieved an accuracy of 98.1% (variance (well within x/3% of expected):, beating traditional competitors such as Random Forest (97.3%) and Support Vector Machine (93.8%). For example, the area under the receiver-operating characteristic curve was 0.995, in
... Show MoreAn easy, eclectic, precise high-Performance Liquid Chromatographic (HPLC) procedure was evolved and validated to estimate of Piroxicam and Codeine phosphate. Chromatographic demarcation was accomplished on a C18 column [Use BDS Hypersil C18, 5μ, 150 x 4.6 mm] using a mobile phase of methanol: phosphate buffer (60:40, v/v, pH=2.3), the flow rate was 1.1 mL/min, UV detection was at 214 nm. System Suitability tests (SSTs) are typically performed to assess the suitability and effectiveness of the entire chromatography system. The retention time for Piroxicam was found to be 3.95 minutes and 1.46 minutes for Codeine phosphate. The evolved method has been validated through precision, limit of quantitation, specificity,
... Show MoreThe cranberry (Vaccinium macrocarpon) is a North American native fruit and contains a very wide variety of phytochemicals, which has several beneficial effects on humans. Aim: The study was designed to assess the protective effect of cranberry fruit extract on selected genotoxic parameters induced by cisplatin in mice’s bone marrow. Methods: 56 male albino mice were randomLy divided into two equal numbers (28 mice) for each part of the study [Part one: for the evaluation of chromosomal aberrations and the mitotic index; and Part two: for the evaluation of micronucleus index]; and for each part, mice were randomly divided into 4 groups: Group I [negative Control/orally-administered normal saline]; Group II [Orally-administered cranberry fr
... Show MoreThe study aimed to prepare psychological measures of intellectual emptiness and mental distraction on university students. The two researchers used the descriptive approach in the two methods of surveying and correlational relations to suit the nature of the research, where the study sample consisted of (101) students of physical education and sports sciences. The phrase- Intellectual emptiness(35) and (34) is a phrase for mental distraction and presented it to experts in psychology, testing and measurement, and the statistical bag for social sciences (spss) was used, and the results of the research showed that intellectual emptiness has a moral relationship with straying among some students of the College of Physical Education
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