A numerical investigation has been performed to study the effect of eccentricity on unsteady state, laminar aiding mixed convection in a horizontal concentric and eccentric cylindrical annulus. The outer cylinder was kept at a constant temperature
while the inner cylinder was heated with constant heat flux. The study involved numerical solution of transient momentum (Navier-Stokes) and energy equation using finite difference method (FDM), where the body fitted coordinate system (BFC) was
used to generate the grid mesh for computational plane. The governing equations were transformed to the vorticity-stream function formula as for momentum equations and to the temperature and stream function for energy equation.
A computer program (Fortran 90) was built to calculate the bulk Nusselt number (Nub) after reaching steady state condition for fluid Prandtl number fixed at 0.7 (air) with radius ratio ( =2.6), Rayleigh number (Ra=200), Reynolds number (Re=50) for both concentric and eccentric cylindrical annulus with different eccentricity ratios (ε=0, 0.25, 0.50, 0.75) and angular positions (φo=0o
, 45o , 90o , 135o , 180o ).
The results show a reasonable representation to the relation between Nusselt number and (ε, φo). Generally, Nub decreased with the increase in (ε and φo). Also, results show that the best thermal performance for the inner cylinder was at the angular
position (φo=0o ) for eccentricity ratio (ε=0.25), while the maximum reduction in the rate of heat transfer for the inner cylinder was at the angular position (φo=180o) for eccentricity ratio (ε=0.75).
Comparison of the result with the previous work shows a good agreement.
Three complexes of copper(II) and iron(II) with mixed ligands acetylacetonebis(thio-semicarbazone)- ABTSH2 and benzaldazine- BA have been prepared and characterized using different physico-chemical techniques including the determination of metal contents, mole-cular weight, measurement of molar conductivity, magnetic moment, molar refraction, infrared and electronic spectra. Accordingly, octahedral complexes having general formulaes [Cu2(ABTSH2)2(BA)2Cl2]Cl2 and [M2(ABTSH2)2(BA)2(SO4)2] {M= Cu(II) or (Fe(II)} have been proposed. The resulted complexes screened for antifungal activity in vitro against the citrus pathogen Aspergillus niger and Fusarium sp. which caused root rot of sugar and the beans pathogen Alternaria sp. All the complex
... Show MoreSuperconducting compound Bi2Sr2-xYxCa2Cu3O10+δ were Synthesized by method of solid state reaction, at 1033 K for 160 hours temperature of the sintering at normal atmospheric pressure where substitutions Yttrium oxide with Strontium. When Y2O3 concentration (0.0, 0.1, 0.2, 0.3, 0.4 and 0.5). All specimens of Bi2Sr2Ca2Cu3O10+δ superconducting compounds were examined. The resistivity of electrical was checked by the four point probe technique, It was found th
six specimens of the Hg0.5Pb0.5Ba2Ca2Cu3-y
This Paper assesses the knowledge management system (KMS) requirements at Al-Ameed University concerning ISO 30401:2022. Specifically, the research aims to ascertain the degree to which international standards have been complied with and gaps that have been identified. A case study was conducted using field observations, interviews, and checklists to assess the institution's compliance with the KMS framework. The level of implementation and documentation of knowledge management processes was assessed using a seven-point scale. The findings reveal that Al-Ameed University has severe gaps in knowledge creation, sharing, and support for knowledge management in terms of strategic leadership. While certain elements like availability of r
... Show MoreThe aim of the present work, was measuring of uranium concentrations in 25 soil samples from five locations of Al-Kut city. The samples taken from different depths ranged from soil surface to 60cm step 15 cm, for this measurement of uranium concentrations .The most widely used technique SSNTDs was chosen to be the measurement technique. Results showed that the higher concentrations were in Hai Al- Kafaat which recorded 1.49 ± 0.054 ppm . The uranium content in soil samples were less than permissible limit of UNSCEAR(11.7ppm).
The Iraqi market for securities in light of financial globalization faces real challenges at the local and international levels, which were reflected in their shadows on the overall economic reality, which imposed the necessity of making fundamental changes in terms of form and content, and from here stems the research problem in the ability of the Iraqi stock market to adapt to the transformations Financial imposed by financial globalization in light of the weakness of the economic structure and its position in the global economy. The research starts from the hypothesis that the Iraqi market for securities in light of financial globalization has an important and significant role in the economic field, through its role in stimula
... Show MoreIn this work, a method for the simultaneous spectrophotometric determination of zinc which was precipitated into deionized water that is in a commercial distribution systems PVC pipe, is proposed using UV-VIS Spectrophotometer. The method based on the reaction between the analytes Zn2+ and 2-carboxy-2-hyroxy-5-sulfoformazylbenze (Zincon) at an absorption maximum of 620nm at pH 9-10. This ligand is selective reagent. Since the complex is colored (blue), its stoichiometry can be established using visible spectrometry to measure the absorbance of solutions of known composition. The stoichiometry of the complex was determined by Job’s method and molar ratio method and found to be 1:2 (M: L). A series of synthetic solution containing different
... Show MoreThis study aims at re-transmit the spirit of the national democratic project of Iraq post of the chaos left by the Daesh terrorist group stage(The Islamic State of Iraq and Syria, ISIS) , Which controlled large parts of Iraq, and had an adverse effect on the political scene in Iraq, inspired everyone that there are deficiencies in the political, economic, religious and ethnic structure of the Iraqi people in non-response to democratic thought.The researcher relied on the hypothesis that " the requirements of building a democratic project are based on the need to provide the requirements ranging from two interrelated aspects, like the institutional aspect and the aspect that related to the general and necessary requirements for the e
... Show MoreBunium is one of the interested genus that grow in different region of Iraq, it is within the family Umbelliferae (Apiaceae), and the species within this family have a considerable fruit characteristics. The species that were chosen in this study are: B. brachyactis (Post) H. Wolff, B. caroides (Boiss.) Hausskn. Ex Bornm., B. chaerophylloides (Regel& Schmalh.) Drude, B. rectangulum Boiss. & Hausskn., B. verruculosum C.C.Towns. and B. avromanum (Boiss.& Hausskn) Drude., the study found that the fruits of these species have 5 protrusions different in size but all have the same number of vittae, but some are semiler in size and some are not, the number of vascular element are varied between these species, anatomical charact
... Show MoreBackground: Moral distress, as one of the most important issues in the nursing profession, can negatively affect the healthcare system. Purpose: To examine the effect of moral distress on professional quality work life. Method: A descriptive cross-sectional study a non-probability sampling method used and total sample collected was (126) of ICU nurses. Results: Moral distress, BO, STS, and, CS among ICUs nurses were moderate. Conclusion: Nurses in ICUs suffered from moderate MD which that effected their BO and STS, and the result can be negative effects on quality of care. Although MD did not affect nurses' CS, it is still an important issue that nurses may face in ICUs