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.
Although many technological improvements are occurring in power production worldwide, power plants in third world countries are still using old technologies that are causing thermal pollution to the water bodies. Power facilities that dump hot water into water bodies are damaging aquatic life. In the study, the impact of the Al Dora thermal power plant on a nearby stretch of Tigris River in Baghdad city was assessed by measuring the temperature of the disposed of hot water in various cross-sections of the selected stretch of Tigris River, including measuring the thermal mixing length. The measurements were conducted in winter, spring, and summer. For field measurements, it was found that the impact of recovery distances
... Show MoreThis work aimed to use conventional PCR to identify Salmonella spp. that were isolated from diarrheal children and healthy and diarrheic dogs based on four virulence genes, hilA, stn, spvR, and marT. Sixteen Salmonella isolates including: 9 isolated from children's diarrhea from three species (S. Typhimurium, S. Enteritidis, S. Typhi) and seven isolated from dogs including (S. Typhimurium, S. Enteritidis, S. Muenchen), were identified primarily by several methods. The PCR products of the 16S rRNA gene were sequenced and examined using BLAST analysis to find differences and similarities between these Iraqi isolates and already-known global strains in order to construct the phylogenetic tree of S.
... Show MoreObjective: the aim of this study is to determine the level of students' knowledge about the environmental health.
Methodology: The cross-sectional study was conducted at the College of Health and Medical Technology in Baghdad
city during the period from 1st march till 1st of July 2012. Data was collected by self-recording of a previously designed
questionnaire to obtain socio-demographic information such as (age, gender, department, year of grade).
Results: The highest rate of students were in the 2nd year followed by the 3rd year, highest rate of students had low
level of knowledge followed by intermediate level of knowledge, while lowest rate of students on had high level of
knowledge .Females had higher level of know
A total of 60 samples of drinking water filtrated by Reverser 0smosis Filtration System from April to October 2012, from different houses in Baghdad – Al Resafa, so as to identify the eggs and cysts of protozoa. Two methods applied direct smear and staining technique with zeal nelson stain, which appeared Tape warm eggs, Ascaris lumbrecoides eggs and oocyst of Cryptospordium sp. This study revealed that total contamination rate with intestinal parasites in tap water were 96.6% this high rate, refers to filtrate tap water by reverse osmosis system was useful to prevent or reduce the contamination of drinking water, in order to reduce risks to public health; So recommended to apply this method at water purification stations. Dis
... Show Moreenjoyed the process of the development of higher education institutions attention of most countries of the world and to reconsider its objectives and programs and administrative and organizational structures, and it was the most important development of the application of Quality Assurance and Accreditation Standards (QAAS) tools, as the aim of these tools to the application of advanced with a far-reaching impact on all of the disciplines in the organization methods education that contribute, and plays a performance audit an important role in verifying the extent to which carried out these institutions activities or programs effectively and efficiently, economic, There are a number of objectives for the search of the most important attem
... Show MoreThis study is concerned with making comparison in using different geostatistical methods for porosity distribution of upper shale member - Zubair formation in Luhais oil field which was chosen to study.
Kriging, Gaussian random function simulation and sequential Gaussian simulation geostatistical methods were adopted in this study. After preparing all needed data which are contour map, well heads of 12 wells, well tops and porosity from CPI log. Petrel software 2009 was used for porosity distribution of mentioned formation in methods that are showed above. Comparisons were made among these three methods in order to choose the best one, the comparing cri
The aim of this study is to highlight this species of gastropoda Cochlicellabarbara( Linnaeus, 1758), which is recorded for the first time in Iraq, which is an exotic animal in this country. It is a terrestrial Molluscan, the study for three months (February, March and April) 2017. In garden houses in Baghdad Al-Karkh, we studied the development stages from the egg to the adult, they lay a hundred of eggs in about (15-20) eggs in each gelatinous sac, the shell with 7 whorls and about 10 mm in length.
From 211 urine samples, Gram negative bacteria were isolated from only 61 urine samples with isolation percentage 28.9%. Escherichia coli were isolated percentage 70.49% while Klebsiella pneumoniae and Psendomonas aeruginosa were 8.19% and 6.55%, respectively.Proteus spp. Were isolated from 9 (14.75%), P. mirablis and P. vulgaris were isolates percentage 11.47% and 3.27%, respectively. Uroepithelial Cell Adhesin (UCA) fimbriae expression by P.mirabilis isolates was detected by the high capacity to adhesion to human uroepithetial cells, the isolate p.mirabilis U7 was adhesion to human uroepithelial cells mean no.30.2 bacteria/cell when grown on luria broth at 37C for 24h, but then grown it’s on luria agar at 37C for 24h the adhesion
... Show MoreQuantitative real-time Polymerase Chain Reaction (RT-qPCR) has become a valuable molecular technique in biomedical research. The selection of suitable endogenous reference genes is necessary for normalization of target gene expression in RT-qPCR experiments. The aim of this study was to determine the suitability of each 18S rRNA and ACTB as internal control genes for normalization of RT-qPCR data in some human cell lines transfected with small interfering RNA (siRNA). Four cancer cell lines including MCF-7, T47D, MDA-MB-231 and Hela cells along with HEK293 representing an embryonic cell line were depleted of E2F6 using siRNA specific for E2F6 compared to negative control cells, which were transfected with siRNA not specific for any gene. Us
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