In this paper, the problem of developing turbulent flow in rectangular duct is investigated by obtaining numerical results of the velocity profiles in duct by using large eddy simulation model in two dimensions with different Reynolds numbers, filter equations and mesh sizes. Reynolds numbers range from (11,000) to (110,000) for velocities (1 m/sec) to (50 m/sec) with (56×56), (76×76) and (96×96) mesh sizes with different filter equations. The numerical results of the large eddy simulation model are compared with k-ε model and analytic velocity distribution and validated with experimental data of other researcher. The large eddy simulation model has a good agreement with experimental data for high Reynolds number with the first, second and third mesh sizes and the agreement increase near the wall of the duct. The percentage error for the large eddy simulation model with experimental data of the (56×56) mesh size is less than 18 % and for the (76×76) mesh size is also less than 17% and for the (96×96) mesh size is less than 16 %. The large eddy simulation model show high stability and do not need extra differential equation like the k-ε model and a great saving in time and computer memory was achieved.
Direct agglutination test was used to evaluate the immunogenicity of three different antigens inoculated in hamsters as one , two and three doses which were: Group (1) inoculated with autoclaved killed Leishmania tropica , Group (2) inoculated with BCG vaccine alone while Group (3) inoculated with mixed antigens (autoclaved killed Leishmania "AKL"+ BCG).(4) Control animals inoculated with phosphate buffer saline. The maximum level of antibody titers were evaluated in animal inoculated with one , two or three dose of mixed antigens (320 , 640 and 1280) respectively when it compared with animals inoculated with corresponding doses of AKL antigen (80 , 160 and 320) respectively. While the minimum level of antibody titers were observed in ani
... Show More
Gas Lasers are important tools that are used in variety purposes, for their low and (cw) output power. The aim of this study was to prepare a way to calculate an optimum stimulated emission cross-section in a gas laser containing a mixture of Xenon and Neon by (30%-70%). The process was a theoretical study of each gas in separate in terms of their physical properties as an active medium. The results of these calculations are logic and more convenient than other mixtures used before
(1)
Fundamentals Concept in Metorology an Introductory Survey - ISBNiraq.org
Patient safety is the main issue in health care organization, the Agency for Healthcare Research and Quality defines it as, “freedom from accidental or preventable injuries produced by medical care. Thus, practices or interventions that improve patient safety are those that reduce the occurrence of preventable adverse events”. The purpose of this study was to evaluate Iraqi pharmacist perception about the culture of patient safety. As well as estimate whether safety is a principal issue in their pharmaceutical practice this study was carried out on 435 pharmacists who are working in community pharmacies in various Iraqi provinces. A survey was distributed via the internet during the period from May to June 2020. A community pharmacy
... Show More
(3)
(2)
(2)
This research tackles the play of Synge "Rider to the Sea" to find out whether the theories of Leech (1983) and Brown and Levinson (1987) can be applied or not to this study. The model of Leech (1983) consists of seven principles and for Brown and Levinson (1987),it consists of two principles of politeness where one of them is positive and the other is negative politeness. It is hypothesed that: 1. There is a relation between the two theories. 2. Synge deals with these theories in such a way to depict his characters. 3. It is also hypothesed that every character deals with these principles in such a way to show the events of the play. The study concludes that there is a relation between the two theories in depicting the characters then it s
... Show MoreThe Civil Rights era has been an era of struggle for the African American in the
Unites states. Thus, many writers devoted their writing to reflect the racism and
discrimination that many have suffered from, among them is Ralph Ellison.
Ralph Ellison is a 20th century African-American writer and scholar best known for
his renowned, award-winning novel Invisible Man. He illustrates the powerful
social and political forces that conspire to keep black Americans in their place,
denying them the right to life, liberty, and the pursuit of happiness guaranteed to all
Americans. Invisible Man is a 1952 novel that addresses many of the social and intellectual
issues facing African-Americans in the twentieth century. It exa