An experimental and numerical study has been 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, annulus inclination angle of (δ = 0˚, 30˚, 60˚ and 90˚). The numerical study was to write the governing equation under an assumptions used Darcy law and Boussinesq’s approximation and then solved numerically using finite difference approximation. It was found that the average Nusselt number depends on (Ra*, Hf, δ and Rr) and the maximum value of the local Nusselt number for vertical cylinder is about two times as large as that of the horizontal case. The results showed that, increasing of fin length increases the heat transfer rate for any fins 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 correlation for Nu in terms of Ra, Rr and δ, has been developed for inner cylinder. A comparison was made between the results of the present work and with other researches for the case without fins and excellent agreement was obtained and reveals deviation less than 5 % for average Nusselt number.
The study was conducted at research station A, department of field crops, college of agricultural engineering sciences, university of Baghdad during summer 2021 to evaluate the effect of boron and some growth regulators on some growth criteria and yield of soybean crop (cv. shimaa). The experiment was carried out according to split plots by using randomized complete block design with three replications. The main plots included three concentrations of boron (75, 150 and 225) mg.L-1, the sub-plots included three levels of growth regulators, spraying kinetin (100 mg. L-1), spraying ethrel (200 mg.L-1) and spraying kinetin (100 mg.L-1) + spraying ethrel (200 mg.L-1) as
... Show MoreThe main topic of this study is central around the independence of Jordanian central bank and the extent of the effectiveness at the bank in leading the monetary policy without interferences or pressures from side of the government. the degree of independence of Jordanian central bank was based on the following based hypothesis following ,there is relationship between the independence of the central bank and the legislative and economical indices. the most important recommendations are degree of independence of the Jordan central bank 43.5% is a good one, but it possible to reach a higher degree than this one by to making some modification on the Jordanian central bank law and by the central bank should be more rigid
... Show MoreObjectives of this project were to study the effect of 60% crude alcoholic extract of the seeds of cyperus esculentuson induced endometritis in the mice . The plant of cyperus esculentuswas extracted by preparing Alcoholic extract 60% . One hundred microliters of saline containing Escherichia coli (104cfu) was used to induce endometritis, by a single intracervicallyinjection, and endometritis developed after 2 days from injection. The mice were divided into five groups, The first group were treated with alcoholic extract of cyperus esculentusextract 150mg/kg body weight, the second group was treated with a daily 3mg per kg body weight of gentamicin given intra peritoneal,The third group was treated by 75mg/kg of cyperus esculentusextract an
... Show MoreUsing an electrochemical polymerization technique at room temperature, poly nicotine amide (PNA) was produced from the monomer nicotine amide (NA) in aqueous solution. The structure of polymer layer generated on the stainless steel surface (316 L) (working electrode) is investigated by Fourier Transmission Infrared Region (FT-IR). The anti-corrosion activity of polymer coating on the stainless steel (SS 316 L) is investigated by electrochemical polarization in 0.20M solution of HCl at 293-323K. The graphene -modified polymer film-coated SS had greater protection efficiency (PE percent) when compared to Nano ZnO -modified polymer film-coated SS. For the corrosion process of SS 316 L, kinetic and thermo-dynamic parameters of activatio
... Show MoreKE Sharquie, AA Noaimi, AM Oweid, JSSDDS, 2009 - Cited by 2
Endometriosis is a common women health disorder that occurs when Endometrial-like tissue grows outside the uterus. This may lead to irregular bleeding , pelvic pain, infertility and other complications. Metformin, because of its activity to improve insulin sensitivity, it is used for the treatment of diabetes; it also has a modulatory effect on ovarian steroid production and has anti-inflammatory properties, all may suggest its possible effect in treatment of endometriosis. This study was planned to determine the effect of metformin on serum levels of&nbs
... Show MoreSome research reports that cognitive grammar (CG) theory has good contributions to teaching English as a foreign language. In this research, the researchers seek to apply this theory and its principles when teaching the simple present tense to Iraqi students who face difficulties in differentiating between the multiple usages of this tense. To achieve this objective, the researchers have conducted an experimental study on a group of 60 Iraqi students in the University of Baghdad, College of Education for Women. Langacker’s (2003) theory has been adopted in the analysis of the cognitive relations to understand the common and different connections of these usages of the simple present. The study has concluded that the cognitive grammar t
... Show MoreThe research has deal with the relationship between organizational justice and empowerment and their impact on the achievement of organizational commitment in the office of Labour and Vocational Training. To study the research problem which is represented a sense that employees with low levels of organizational justice and empowerment and the reflection on the organizational commitment of the employees, so that Has been collecting data and information relating to research by designing a questionnaire, were distributed to a sample of (50) people in the office mentioned, and the results of the study to confirm the research hypotheses. and the key results of the research was the presence of correlation relationships and the effect o
... Show MoreMany studies have evaluated the effect of platelet rich plasma (PRP) in the treatment of non-union fractures but few studies have investigated their effect on the union of femoral neck fractures or their functional outcome in young adults. The aim of this study was to evaluate the union time and functional outcome in young adult patients with femoral neck fracture managed by three cannulated screws injected with PRP and those managed by fixation only. This prospective study included 24 patients diagnosed with femoral neck fractures within 24 hours of presentation. Twelve cases in group A were managed by closed reduction and three cannulated screws fixation injected with PRP; twelve patients in group B were managed only by closed reduction a
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