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.
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The present study aimed to investigate the possible protective effect of cafestol against doxorubicin-induced chromosomal and DNA damage in rat bone marrow cells. Wistar
Albino rats of both sexes were administered cafestol (5mg/kg body weight once
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Background: Prolonged use of low-dose estrogen ''20 micrograms or less" Combined oral contraceptive pill (that have estrogen and progesterone steroid hormone) had an effect on bone turnover .Bone mineral density is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. The aim of the study: The aim of this study was to investigate the effect of low dose oral contraceptive pill on the cortical thickness (in millimeter) and bone mineral density at the mandibular cortex of mental and gonial regions in Hounsfield unit(HU) using spiral computed tomography. Material and method: This prospective study was conducted on computed tomographic image of 100 women aged between (20-40) years .The collected sample includes
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Objectives: The study aims to identify the effects of an educational program on patients’ knowledge about vascular access care and to find out the relationship between patients knowledge scores and their selected demographic variable. &
... Show MoreThe earthly music has a clear influence on the religious music in the musical culture to read and recite the Holy Quran in the city of Baghdad. This research deals with this subject in an attempt to reveal the influence of the Iraqi maqam in the recitation of Hafiz Khalil Ismail. The methodological framework of the research included the problem of research and its importance as it is useful to the Iraqi schools concerned with the recitation of the Holy Quran in Iraq. The theoretical framework included three sections that serve the literature of its subject: the first is (Iraqi maqam), the second is (the recitation of the Holy Quran) and the third is (the biography of Hafez Khalil Ismail).
The most important procedures
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The purpose of this paper is applying the robustness in Linear programming(LP) to get rid of uncertainty problem in constraint parameters, and find the robust optimal solution, to maximize the profits of the general productive company of vegetable oils for the year 2019, through the modify on a mathematical model of linear programming when some parameters of the model have uncertain values, and being processed it using robust counterpart of linear programming to get robust results from the random changes that happen in uncertain values of the problem, assuming these values belong to the uncertainty set and selecting the values that cause the worst results and to depend buil
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This study aimed to identify the attitudes of school teachers and principals at basic government schools in Ajloun governorate towards the inclusion of disabled students at basic schools, and investigate how they will accept the merger. To achieve the purpose of this study, a questionnaire containing 35 items was administered to school teachers and principals to measure their attitudes toward the inclusion of disabled students in regular schools. The sample of this study consisted of 43 male teachers and (74) female teachers and principals. The frequency, normal distribution, arithmetic means and t-test were used to analyze the data of present study. The findings showed that there
... Show MoreThe value of time out as a time not count of official time form the game like four periods and extra time also it considered a great interest if used well thru the game , the importance of this problem is not using well the time out and when the coach ask for time out and how to invest this time legally to make good results also there is no observing system as the researcher see gives the reality image that the coach is successful lead the game when he takes time out . The goals of research that knowing on numbers of time out for excellent teams in Iraq (first &second) stages and putting special inventory reverse reality of asking time out (positive &negative) on playing basketball , the hypothesis of research that tell the time out effect
... Show MoreThe objective of this in vivo study is to investigate the effects of 337.1 nm pulsed N2 laser on cellular immune response represented by lymphocyte transformation capacity and phagocytosis activity in laboratory animals. The samples include 60 adult male BALB/c mice, were divided into control group and experimental groups. The experimental groups were divided into two main groups according to the time period after N2 laser irradiation. Each group was divided into 9 subgroups which exposed to N2 laser radiation at different values of pulse repetition rates and exposure times. The results of immunological tests demonstrated that the exposure to 180 J/cm2 of N2 laser radiation induce adverse effect to cellular immune response. The results o
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