Preferred Language
Articles
/
alkej-24
The Effect of Restriction Shape On Laminar Natural Convection Heat Transfer In A Vertical Circular Tube
...Show More Authors

Natural convection heat transfer is experimentally investigated for laminar air flow in a vertical circular tube by using the boundary condition of constant wall heat flux in the ranges of (RaL) from (1.1*109) to (4.7*109). The experimental set-up was designed for determining the effect of different types of restrictions placed at entry of heated tube in bottom position, on the surface temperature distribution and on the local and average heat transfer coefficients. The apparatus was made with an electrically heated cylinder of a length (900mm) and diameter (30mm). The entry restrictions were included a circular tube of same diameter as the heated cylinder but with lengths of (60cm, 120cm), sharp-edge and bell-mouth. The surface temperature along the cylinder surface for same heat flux would be higher values for circular restriction with length of (120cm) and would be smaller values for bell-mouth restriction. The results show that the local Nusselt number (Nux) and average Nusselt numberare higher for bell-mouth restriction and smaller values for (120cm) restriction. For all entry shape restrictions, the results show that the Nusselt number values increases as the heat flux increases. From the present work an empirical correlations were obtained in a form of (Log) versus (Log) for each case investigated and obtained a general correlation for all cases which reveals the effect of restriction existence on the natural convection heat transfer process in a vertical circular tube.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Synthesis and Characterization of [2-(carboxy methylene-amino)-phenyl imino] acetic acid (L) and its some metal complexes
...Show More Authors

New Schiff base, namely [2-(carboxy methylene-amino)-phenyl imino] acetic acid (L) and its some metal complexes [LCo.2H2O], [LNi.2H2O], [LCu].3H2O, [LCd.2H2O], [LHg.2H2O] and [LPb.2H2O], were reported and characterized by elemental analysis, metal content, spectroscopic methods, magnetic moments and conductivity measurements, it is found that the geometrical structures of these complexes are octahedral [Co(II), Ni(II), Cd(II), Hg(II), Pb(II) and square planar Cu(II).The complexes have been found to posses 1:1 (M:L) stoichiometry

View Publication Preview PDF
Crossref
Publication Date
Tue Jan 06 2009
Journal Name
مجلة ديالى للعلوم الانسانية
Synthesis and Characterization of Novel Bidentate Ligand type NO and Its Complexes with (CoII , NiII ,CuII and ZnII)
...Show More Authors

The [2-aminobenzothiazole]was reacted with [2,4,6 triyhydroxy-acetophenon monohydrate] to give a new ligand [2-N-2,4,6-trihydroxyacetophenonyliden benzothiazole] [H3L]. This ligand was reacted with metal ions ( CoII, NiII,CuII and ZnII) in methanol as solvent with ( 1:2 ) metal : ligand ratio to give a series of new complexes with general formula [ M(H2L)2],(where:M= CoII, NiII ,CuIIand, ZnII).All compounds were characterized by spectroscopic methods ( I.R , U.V – vis,HPLC) atomic absorption, along with chloride content and conductivity measurements. According to the data of these measurements we suggested a tetrahedral

Publication Date
Tue Jan 01 2013
Journal Name
Ibn Al-haitham Jour. For Pure & Appl. Sci.
Synthesis and Spectroscopic of Some new Metal Ions Complexes's with [N-(4-Methoxy Benzoyl Amino)-Thioxo Methyl] Leucine
...Show More Authors

A new ligand [N-(4-methoxy benzoyl amino)-thioxo methyl ] leucine (MBL) was prepared from the reaction of (4-methoxy benzoyl isothiocyanate with leucine acid in molar ratio (l:l), it was characterized by elemental analysis (C.H.N.S), FT-IR, UV-Vis, 1H and 13C-NMR. The complexes of the bivalent ions (Mn, Fe, Co, Ni, Cu, Zn, Cd and Hg ) have been prepared and characterized too. The structural was established by elemental analysis (C.H.N.S), FT-IR, UV-Vis spectra, conductivity measurements atomic absorption and magnetic susceptibility and determination of molar ration (M:L). The complexes showed characteristic behavior of tetrahedral geometry around the metal ions except with (Cu) complex showed square planer.

Publication Date
Tue May 02 2023
Journal Name
Social Science Journal
An Investigation of Microstructure Analysis for World Health Organizatioan Speeches during Covid-19 Pandemic: Adopted Van Dijk Theory
...Show More Authors

Publication Date
Fri Apr 01 2022
Journal Name
Chemical Methodologies
Design, Synthesis of Imidazolone and Oxazepine Derivatives Bearing Imidazo (2, 1-b) Thiazole along with its Antimicrobial Activity
...Show More Authors

A new methodology was applied to the synthesis of new imidazolones and oxyazepine derivatives containing imidazo thiazole fused rings. Starting with 5-(4-bromo phenyl) imidazo (2, 1-b) thiazole, which was synthesized using the standard procedure, the Carbaldehyed group was introduced at position 6 of 5-(4-bromo phenyl) imidazo (2, 1-b) thiazole. Then, this 6-carbaldehyed derivative was condensed with different substituted aromatic amines to afford new Schiff bases. The latter were cyclized into new oxazepine and imidazolone derivatives by using phthalic anhydride and glycine, respectively. These new derivatives were characterized by using FT-IR, 1HHNMR, and 13CNMR spectra, as well as examined (evaluated) for anti-bacterial and anti-fungal a

... Show More
View Publication Preview PDF
Scopus (12)
Scopus Clarivate
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Synthesis of New Heterocyclic Derivatives from 4-(3, 5-Dimethyl-1-phenyl-1H-pyrazol-4-ylazo)- benzoic acid
...Show More Authors

In this work pyrazolin derivatives were prepared from the diazonium chloride salt of 4-aminobenzoic acid. Azo compounds were prepared from the reaction of an ethanolic solution of sodium acetate and calculated amount of active methylene compound namely, acetyl acetone to obtain the corresponding hydrazono derivative (1). Cyclocondensation reaction of compounds (1) with hydrazine hydrate and phenyl hydrazine in boiling ethanol affording the corresponding pyrazoline-5-one derivatives of 4-aminobenzoic acid (2,3). Then compound (3) was reacted with thionyl chloride to give the corresponding acid chloride derivative(4), followed by conversion into the corresponding acid hydrazide derivative (5) carboxylic acid thiosemicarbazide (11), esters

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jun 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Micro-Bubble Flotation for Removing Cadmium Ions from Aqueous Solution: Artificial Neural Network Modeling and Kinetic of Flotation
...Show More Authors

In this work, microbubble dispersed air flotation technique was applied for cadmium ions removal from wastewater aqueous solution. Experiments parameters such as pH (3, 4, 5, and 6), initial Cd(II) ions concentration (40, 80, and 120 mg/l)  contact time( 2, 5, 10 , 15, and 20min), and surfactant (10, 20and 40mg/l) were studied in order to optimize the best conditions .The experimental results indicate that microbubbles were quite effective in removing cadmium ions and the anionic surfactant SDS was found to be more efficient than cationic CTAB in flotation process. 92.3% maximum removal efficiency achieved through 15min at pH 5, SDS surfactant concentration 20mg/l, flow rate250 cm3/min and at 40mg/l Cd(II) ions initial co

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Fri Jul 01 2016
Journal Name
Colloids And Surfaces A: Physicochemical And Engineering Aspects
Stability and thermophysical properties of water-based nanofluids containing triethanolamine-treated graphene nanoplatelets with different specific surface areas
...Show More Authors

tA novel synthesis procedure is presented for preparing triethanolamine-treated graphene nanoplatelets(TEA-GNPs) with different specific areas (SSAs). Using ultrasonication, the covalently functionalizedTEA-GNPs with different weight concentrations and SSAs were dispersed in distilled water to prepareTEA-GNPs nanofluids. A simple direct coupling of GNPs with TEA molecules is implemented to synthesizestable water-based nanofluids. The effectiveness of the functionalization procedure was validated by thecharacterization and morphology tests, i.e., FTIR, Raman spectroscopy, EDS, and TEM. Thermal conduc-tivity, dispersion stability, and rheological properties were investigated. Using UV–vis spectrometer, ahighest dispersion stability of 0.876

... Show More
Crossref (93)
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Revista De Chimie
Synthesis, Characterization and Antibacterial Activity from Mixed Ligand Complexes of 8-Hydroxyquinoline and Tributylphosphine for Some Metal Ions
...Show More Authors

Co+2, Ni+2, Cu+2 as well Zn+2 compounds mixed ligand from 8-hydroxyquinoline(8-HQ) also tributylphosphine (PBu3) have been attended at aquatic ethyl alcohol for (1:2:2) (M:8-HQ:PBu3). Produced complexes have been identified by utilizing atomic absorption flame, FT-IR as well UV-Vis spectrum manners also magnetic susceptibility as well as conductivity methods. At addendum antibacterial efficiency from the ligands as well complexes oboist three species about bacteria have been as well examined. Ligands and their complexes show good bacterial efficiencies. Of the gained datum the octahedral geometry was proposed into whole prepared complexes

Publication Date
Wed Feb 10 2021
Journal Name
Materials Today: Proceedings
Characterizations and testing some mechanical properties of prepared PMMA-Lithium disilicate glass ceramic composite for denture base application
...Show More Authors

Denture bases are fabricated routinely using Poly(methyl methacrylate) (PMMA) acrylic resin. Yet, it is commonly known for its major drawbacks such as insufficient strength and ductility. The purpose of this study was to improve the performance of PMMA acrylic resin as a denture base material by reinforcement with surface treated lithium disilicate glass ceramic powder. The ceramic powder was prepared by grinding and sieving IPS e.max CAD MT blocks. Then, the powder was surface treated with an organosilane coupling agent (TMSPM) and added to PMMA in amount of 1%, 3%, 5% and 7% by weight. Characterizations of the powder was done by particle size analysis, XRD and FTIR. Transverse strength, Impact strength, Shore D hardness and surface roughn

... Show More
View Publication
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref