Two-dimensional unsteady mixed convection in a porous cavity with heated bottom wall is numerically studied in the present paper. The forced flow conditions are imposed by providing a hydrostatic pressure head at the inlet port that is located at the bottom of one of the vertical side walls and an open vent at the top of the other vertical side wall. The Darcy model is adopted to model the fluid flow in the porous medium and the combination effects of hydrostatic pressure head and the heat flux quantity parameters are carefully investigated. These governing parameters are varied over wide ranges and their effect on the heat transfer characteristics is studied in detail. It is found that the time required to reach a desired temperature at the bottom wall decreases with heat flux and pressure head increase. The higher heat flux quantities leaves wider regions near the top wall at lower temperatures which is important in most engineering applications like drying.
(1)
The solidification process in a multi-tube latent heat energy system is affected by the natural convection and the arrangement of heat exchanger tubes, which changes the buoyancy effect as well. In the current work, the effect of the arrangement of the tubes in a multi-tube heat exchanger was examined during the solidification process with the focus on the natural convection effects inside the phase change material (PCM). The behavior of the system was numerically analyzed using liquid fraction and energy released, as well as temperature, velocity and streamline profiles for different studied cases. The arrangement of the tubes, considering seven pipes in the symmetrical condition, are assumed at different positions in the system, i
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(17)
(16)
The erythrocyte aggregation is an important physiological phenomenon in the circulation of blood. It is a basic characteristic of normal blood that plays a major role in the cardiovascular system, especially in the microcirculation. This study explained the kinetics of single cells rouleaux formation one- dimensional aggregate and three- dimensional aggregate, during simultaneous, and the effect of hematocrit on the process of aggregation and sedimentation. The present study was done on forty one healthy subjects. Laser light is passed through a well mixed sample of blood and the forward scattered light intensities recorded continuously. The samples were prepared with different hematocrit, (10%, 15%, 20%, and 25%). Increasing
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Mixed metal ligand complexes is reported with Curcumin (CUM) as a primary ligand and 1:10-phenanthroline (phen ) as secondary ligand. The structures of these complexes are confirmed by using FT-IR and UV- electronic spectroscopies, magnetic moments, melting points , molar conductivity measurements .and the metal % analysis revealed that the complexes analyze indicates a six coordinated as[M(CUM)( Phen)2]Cl, M=Mn (II), Co(II), Ni(II),Cu(II) ,Zn(II) , Cd(II) , Hg(II) and [M’ (CUM)( Phen)2]Cl2 M’= Cr(III) &. Fe(III). In-vitro antimicrobial studies on ( Curcumin and 1:10-phenanthroline ligands and mixed metal ligand complexes against {(Bacillus subtilis (G+) , Esherichia Coli (G-) and as well as antifungal activities against Candida albican
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(9)
In this work, lanthanium (III) complexes were synthesized using by Schiff base ligand (L) derived from benzaldehyde and o-aminoaniline with five amino acids (AA) from glycine (Gly), L-alanine (Ala), L-valine (Val), L-asparagine (Asp) and DL- phenylalanine (Phe). The Schiff base ligand has been characterized by elemental analysis, (MASS, FTIR, 1HNMR, 13CNMR, UV-VIS) electronic spectra. The structures of the new complexes have been described of analysis of elements, molar conductivity, (UV-Vis electronic, FTIR, mass) spectra also magnetic moment. The molar conductivity values of the complexes indicat this every of complexes are electrolytes and other analytical studies reveal octahedral geometry for La (III) ion. The Schiff base ligand, five
... Show MoreSome metal ions (Mn
+2
, Fe
+2
,Co
+2
,Ni
+2
,Cu
+2
, Cd
+2
and Hg
+2
) complexes of N-acetyl
Tryptophan( AcetrpH) and (2, 2′-bipyridine) (2, 2′-Bipy)have been synthesized and then
characterized on the basis of their FT-IR, UV-Vis spectroscopy, magneticsuscptibity
conductivity measurements and atomic absorption;from the results obtained and the propsed
molecular structure for these complexes as octahedral geometry,the following general formula
has been given for the prepared complexes.
[M
+n
(Acetrp)2(2, 2′-Bipy)].
Where M= Mn
+2
, Fe
+2
,Co
+2
,Ni
+2
,Cu
+2
, Cd
+2
,Hg
+2
(Acetrp)
-=Ligand ion(N-acetyl
A novel Schiff base ligand [N1-benzylidenebenezene-1,2-diamine(L) = C20H16N2] was prepared through intensification of benzaldehyde (C6H5CHO) and O- amino aniline O-C6H4(NH2)2 in ethanol with 8-Hydroxyquinoline (8HQ) . Formed compounds were acquired of 1:1:2 molar proportion reactions for metal ions and ligands (L) and 2(8HQ) during reaction for MCl2 .nH2O salt products complexes conformable into the forms [M(L)(8HQ)2] ,where M = Mn(II),Co(II) and Ni(II). Whole the compounds were identified during the basis of their; FT-IR and U.V spectrum, melting point, molar conduct, identify of the percentage from the metal at the complexes via flame (AAS), C, H and N content of the Schiff base (L) and metal complexes were analysis and magnetic susceptib
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