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.
Background: the primary objective for many researches carried out in dental implantology was to reduce the period needed for functional implant loading, simvastatin (cholesterol lowering medication) had many pleiotropic effects, one of which was increasing bone density around titanium implants (1) and subsequently establishing faster osseointegrated dental implants (2,3). This study aims to reduce the period of time needed to establish secondary stability of dental implant measured in ISQ (Implant Stability Quotient) by investigating the effect of orally administered simvastatin on bone. Materials and methods: simvastatin tablets (40mg/day for three months) were administered orally for 11 healthy women aged (40-51) years old who received 1
... Show MoreBackground: Mental health is integrated into PHC as a strategy of WHO to fill the gap in mental health treatment. Part of this strategy needs a level of task shifting so that mental health care is provided by different level of PHC workers and not only specialists such as psychiatrists and psychologists.
Objectives: To assess the knowledge and attitudes of family doctors regarding the provision of psychological health in PHCC and if there is an association between the certificates of these family doctors and their Knowledge and attitudes to psychological health.
Subjects and Methods: A cross-sectional descriptive study with analytic elements was conducted in 8 famil
... Show MorePoly aniline-formaldehyde/chitosan composite (PAFC) was prepared by the in situ polymerization method. It was characterized by FTIR spectroscopy in addition to SEM, EDS and TGA techniques. The adsorption kinetics of malachite green dye (MG) on (PAFC) were studied for various initial concentrations (20, 30 and 40) mg/L at three temperatures (308, 313 and 318) K. The influence factors of adsorption; adsorbent dose, contact time, initial concentration and temperature were investigated. The kinetic studies confirmed that adsorption of MG obeyed the pseudo-second-order model and the adsorption can be controlled through external mass transfer followed by intraparticle diffusion mass transfer. A study of th
A total of 247 Mallard ( Anas platyrhynchos platyrhynchos L.) from Baghdad and Kut were examined for the Cestodes Diorchis stefanskii Sobolevicanthes gracilis; Hymenolepis mastigopraditae and the Nematode Amidostomum acutum in the first time in Iraq . Among these , 151 birds were found infected by these helminthes It has been found small nodules on the external surface of the intestine , Ulceration of mucosa inflammatory infiltrate , Oedemats changes and hyperplasia in the section of infected intestine were noticed.
The method binery logistic regression and linear discrimint function of the most important statistical methods used in the classification and prediction when the data of the kind of binery (0,1) you can not use the normal regression therefore resort to binary logistic regression and linear discriminant function in the case of two group in the case of a Multicollinearity problem between the data (the data containing high correlation) It became not possible to use binary logistic regression and linear discriminant function, to solve this problem, we resort to Partial least square regression.
In this, search the comparison between binary lo
... Show MoreAbstract. In this work, Bi2O3 was deposited as a thin film of different thickness (400, 500, and 600 ±20 nm) by using thermal oxidation at 573 K with ambient oxygen of evaporated bismuth (Bi) thin films in a vacuum on glass substrate and on Si wafer to produce n-Bi2O3/p-Si heterojunction. The effect of thickness on the structural, electrical, surface and optical properties of Bi2O3 thin films was studied. XRD analysis reveals that all the as deposited Bi2O3 films show polycrystalline tetragonal structure, with preferential orientation in the (201) direction, without any change in structure due to increase of film thickness. AFM and SEM images are used to investigate the influences of film thickness on surface properties. The optical measur
... Show MoreThis study involved the evaluation of Alcoholic extract of Nerium Oleander L. plant that have a promising anticancer cell. This extract was compared to the well known anticancer drug Cis – Platinum by utilizing an in vivo system in female Albino mice. The first direction was cytogenetically using the mitotic Index of bone marrow cells as a parameter for the cytotoxic effect of this extract. The second direction was enzymatical using a widely distributed enzyme GOT in the different organs of mice: Liver , kidney , spleen and lung . Animals were treated with three doses of Cis-platin , 50 , 200 and 350 Mg/mouse for three days . The same doses were used for the other extract . This study showed that the extract have a promising anticance
... Show MoreIn regression testing, Test case prioritization (TCP) is a technique to arrange all the available test cases. TCP techniques can improve fault detection performance which is measured by the average percentage of fault detection (APFD). History-based TCP is one of the TCP techniques that consider the history of past data to prioritize test cases. The issue of equal priority allocation to test cases is a common problem for most TCP techniques. However, this problem has not been explored in history-based TCP techniques. To solve this problem in regression testing, most of the researchers resort to random sorting of test cases. This study aims to investigate equal priority in history-based TCP techniques. The first objective is to implement
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This research dealt with highlighting the images of marriage through the modern means of communication and the legal ruling for it. Dowry even be knotted on them; because they are then one of the parties to the contract and contracted in one contract, and this is prohibited by law and law and common sense.
It turns out that it is permissible to advertise marriage through the Internet in accordance with the rules and standards that preserve values and morals and safeguard dignity and chastity. The acts in Islamic law are vested with intentions. If intentions are true, then the act is true, and Internet marriage is what falls under this order.<
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