Conjugate heat transfer has significant implications on heat transfer characteristics, particularly in thick wall applications and small diameter pipes. In this study, a three-dimensional numerical investigation was carried out using commercial CFD software “ANSYS FLUENT” to study the influence of conjugate heat transfer of laminar flow in mini channels at constant heat flux wall conditions. Two parameters were studied and analyzed: the wall thickness and thermal conductivity and their effect on heat transfer characteristics such as temperature profile and Nusselt number. Thermal conductivity of (0.25, 10, 202, and 387) W/m2C and wall thickness of (1, 5, and 50) mm were used for a channel of (1*2) mm cross
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The public procurement crisis in Iraq plays a fundamental role in the delay in the implementation of construction projects at different stages of project bidding (pre, during, and after). The procurement system of any country plays an important role in economic growth and revival. The paper aims to use the fuzzy logic inference model to predict the impact of the public procurement crisis (relative importance index and Likert scale) was carried out at the beginning to determine the most important parameters that affect construction projects, the fuzzy analytical hierarchy process (FAHP) to set up, and finally, the fuzzy decision maker's (FDM) verification of the parameter for comparison with reality. Sixty-five
... Show MoreEssential oils were extracted from Syzqiumoramac clove, Nigella sativa and eucalyptus oil for purpose of studying effect of these oils on adult cockroaches as repellents and extent of their attraction to them by treating biscuits with three concentrations (0.5, 0.25,1%). The results showed that clove oil was significantly more repellent than black seed oil at a concentration (1%), as average for five days was (0.32) compared to black seed oil (1.36). Insects attracted towards lunch averaged 7.58, 14 and this indicates fading of repellent effect due to penetration of the aroma of volatile clove oil. Results also showed that clove oil has a more lethal effect by direct spraying on nymphs and adults than black seed oil, as mortality in
... Show MoreThe present study was identified the type of bacterial contamination of Iraqi banknotes currency (Iraqi dinars) in circulation. 68 Iraqi banknotes currency of different denominations samples were randomly gathered from different locations and different occupational groups in Baghdad city. The results showed 61 (89.70%) of the samples were determined to be contaminated with bacteria, whereas 7 (10.29%) were confirmed to be sterile. A total of 11 different species of bacteria resulting in 72 isolates were found from those 61 contaminated Iraqi banknotes currency. Based on culture, morphological and biochemical tests, 11 isolates were identified as Bacillus sp., Staphylococcus aureus, Staphylococcus epidermidis, Corynebacterium diphtheria, Leu
... Show MoreWe introduced the nomenclature of orthogonal G -m-derivations and orthogonal generalized G -m-derivations in semi-prime G -near-rings and provide a few essentials and enough provision for generalized G -n-derivations in semi-prime G -near-rings by orthogonal.
This study aimed to investigate the impact of implementing Glycetin by injection on the productive features of local Iraqi chickens. 100 female hens and 20 roosters from a local Iraqi chicken population, at age 26 weeks. The sample was divided into three groups, in addition to a control group. Each experimental group had 25 female hens, with the same procedure being performed for each individual hen, and 20 roosters, which were reared separately for the purpose of artificial insemination. The avian specimens were housed in separate enclosures, and the experimental conditions were allocated as follows: the initial condition (Control Group) did not receive any injections, whereas condit
Industrial wastewater containing nickel, lead, and copper can be produced by many industries. The reverse osmosis (RO) membrane technologies are very efficient for the treatment of industrial wastewater containing nickel, lead, and copper ions to reduce water consumption and preserving the environment. Synthetic industrial wastewater samples containing Ni(II), Pb(II), and Cu(II) ions at various concentrations (50 to 200 ppm), pressures (1 to 4 bar), temperatures (10 to 40 oC), pH (2 to 5.5), and flow rates (10 to 40 L/hr), were prepared and subjected to treatment by RO system in the laboratory. The results showed that high removal efficiency of the heavy metals could be achieved by RO process (98.5%, 97.5% and 96% for Ni(II),
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