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joe-1979
MIXED CONVECTIVE AND RADIATIVE HEAT TRANSFER IN A HORIZONTAL CONCENTRIC AND ECCENTRIC CYLINDRICAL ANNULI
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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.

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Publication Date
Sun Sep 01 2019
Journal Name
Baghdad Science Journal
Symmetric and Positive Definite Broyden Update for Unconstrained Optimization
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Broyden update is one of the one-rank updates which solves the unconstrained optimization problem but this update does not guarantee the positive definite and the symmetric property of Hessian matrix.

In this paper the guarantee of positive definite and symmetric property for the Hessian matrix will be established by updating the vector  which represents the difference between the next gradient and the current gradient of the objective function assumed to be twice continuous and differentiable .Numerical results are reported to compare the proposed method with the Broyden method under standard problems.

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Publication Date
Mon Jul 01 2019
Journal Name
J. Pharm. Sci. & Res.
Methods of Synthesis Phthalimide Derivatives and Biological Activity-Review
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Phthalimide formation of Phthalic anhydride with various amines using microwave or without a method with the difference of the catalyst used in a prepared Phthalimide, either structure general are C6H4CONRCO and used as starting materials in synthesis several compounds derivative phthalimides are an important compounds because spectrum wide biological activities including Antimicrobial activity, anticonvulsant activity, Anti-inflammatory activity,Analgesic activity, Anti- influenza activity and Thromboxane inhibitory activity

Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
the periodic coincidence points of continuius maps and lindemann's
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this paper give a proof of known conditions for the existence of peridic conincidence points of continuius maps using lindemann theotem on transcendental numbers

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Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Determining Optimum Oil Separator Size and Optimum Operating Pressure
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The optimum separators operating pressure is determined by using flash calculations and equilibrium ratios. In this study, the optimum separator size for Jambur field is calculated by using equations introduced by Arnold and Stewart and API12J Specification [1]. Because Jambur field has a high production rate two conditions are taken in the study to determine separator size, first based on production rate 80,000 bbl/day and second based on split the production between two banks A and B (40,000 bbl/day for each bank). The calculation resulted in optimum separator pressure for the first stage of 700 psi, and the second stage of 300 psi, and the third stage of 120 psi. The results show that as the number of stages increased above three-stag

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Publication Date
Mon Mar 27 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Phytochemical Investigation and Antioxidant Activity of Iraqi Tribulus terrestris
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The aim of the present study was to characterize the Iraqi Tribulus terrestris for the presence of biologically active phyto-chemicals using methanolic extracts of the plant (aerial parts) by Gas Chromatography –Mass spectrometry (GC/MS), while the mass spectra of the compounds found in the extract was matched with the National Institute of Standards and Technology (NIST) library , in addition to study the antioxidant activity of plant extract , results confirmed the presence of therapeutically potent compounds in the Iraqi Tribulus terrestris extract predominantly alkaloids, flavonoids, saponins, tannins and terpenoids. Antioxidant potential of Iraqi Tribulus terrestris

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Publication Date
Sun Jun 05 2016
Journal Name
Baghdad Science Journal
Gelatin Grafted Methyl Nadic Anhydride and Substitution With Salbutamol
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Gelatin a promising biomaterial which is useful and interesting natural polymer which offer possibilities of chemical modification through grafted copolymerization with an saturated acid anhydride such as methyl nadic anhydride formatted gelatin –g- methyl nadic anhydride copolymer (A1), then modified to its corresponding polymer (A2) by substituted salbutamol as useful derivative as biomaterial .the prepared drug biopolymer was characterization by FTIR spectroscopy and thermal analysis was studied controlled drug release was measured in different buffer solution at 37C0 .

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Publication Date
Mon Jul 01 2019
Journal Name
Journal Of Physics: Conference Series
Production and antibacterial activity of biosurfactant from Saccharomyces cerevisiae
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Abstract<p>A total of four types of instant dry yeast <italic>Saccharomyces cerevisiae</italic> which are Gloripan, Swan, Super Man (China) and Saf (Turkey), were obtained from the local market in Baghdad, Iraq. All the types were identified according to their morphological characteristics and screened for their ability to produce biosurfactant by oil spread method. Biosurfactant was extracted and partially purified by precipitation with ammonium sulfate at saturation ratio75%. Antibacterial activity of crude and partially purified biosurfactant was tested against twenty isolates of <italic>Pseudomonas aeruginosa</italic> and the results showed that crude biosurfactant has no</p> ... Show More
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Publication Date
Wed Sep 10 2014
Journal Name
Monthly Notices Of The Royal Astronomical Society
Warm dark haloes accretion histories and their gravitational signatures
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We study clusters in warm dark matter (WDM) models of a thermally produced dark matter particle 0.5 keV in mass. We show that, despite clusters in WDM cosmologies having similar density profiles as their cold dark matter (CDM) counterparts, the internal properties, such as the amount of substructure, show marked differences. This result is surprising as clusters are at mass scales that are a thousand times greater than that at which structure formation is suppressed. WDM clusters gain significantly more mass via smooth accretion and contain fewer substructures than their CDM brethren. The higher smooth mass accretion results in subhaloes which are physically more extended and less dense. These fine-scale differences can be probed by strong

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Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The Development of the Suez Canal and Projects Competitors
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The area around the Suez Canal has been chosen particularly  Sinai  to implement the new Suez Canal project parallel to the original 72-km-long channel due to the importance of the commercial site of the Arab Republic of Egypt, competing with shipping lanes, to accommodate the increasing maritime traffic  passing through the Suez canal, and to provide special services for trade world and reduce the economic cost of marine trip. The establishment of six tunnels for automobile and railway transport to Sinai The cost of the establishment of this new channel  and the establishment of the tunnels about (2.8) billion, of which 4 billion cost of the new channel. Project implementation period is one year. The new proj

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Publication Date
Sun Jul 01 2018
Journal Name
International Journal Of Geotechnical Earthquake Engineering
Impact Induced Responses of Saturated and Dry Dense Sand
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The present article includes an experimental study of the behavior of dry and saturated dense sandy soil under the action of a single impulsive load. Dry and saturated dense sand models were tested under impact loads. Different falling masses from different heights were conducted using the falling weight deflectometer (FWD) to provide the single pulse energy. The responses of dense soils were evaluated at surface of soil under impact load. These responses include; displacements, velocities, and accelerations that are developed due to the impact acting at top and the displacement at different depths within the soil using the falling weight deflectometer (FWD) and accelerometers (ARH-500A waterproof, and low capacity acceleration tran

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Scopus (7)
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