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
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
Removal of Malachite Green from Aqueous Solution using Ficus Benjamina Activated Carbon-Nonmetal Oxide synthesized by pyro Carbonic Acid Microwave
...Show More Authors

Activated carbon derived from Ficus Binjamina agro-waste synthesized by pyro carbonic acid microwave method and treated with silicon oxide (SiO2) was used to enhance the adsorption capability of the malachite green (MG) dye. Three factors of concentration of dye, time of mixing, and the amount of activated carbon with four levels were used to investigate their effect on the MG removal efficiency. The results show that 0.4 g/L dosage, 80 mg/L dye concentration, and 40 min adsorption duration were found as an optimum conditions for 99.13% removal efficiency. The results also reveal that Freundlich isotherm and the pseudo-second-order kinetic models were the best models to describe the equilibrium adsorption data.

 

View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Apr 03 2023
Journal Name
Journal Of Educational And Psychological Researches
Critical Thinking Skills of A’Sharqiah University Students According to California Critical Thinking Skills Test and Its Relationship to Some Variables
...Show More Authors

Abstract

The research aims to measure the level of critical thinking skills among students of A’Sharqiah University in the Sultanate of Oman, as well as identify the level of their availability based on the variables: gender, academic level, school year, cumulative average, and general diploma / high school ratio. The researchers used the descriptive approach. To achieve the objectives of the study, they used The California Test for Critical Thinking Skills Picture (A) after evaluation (Farraj, 2006). It was applied to a sample of (487) students from A’sharqiah University. The results of the study found that the critical thinking skills of A’sharqiah University students are below the educationally acceptabl

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 01 2024
Journal Name
Minar International Journal Of Applied Sciences And Technology
PREPARATION, CHARACTERIZATION AND EVALUATE THEIR BIOLOGICAL ACTIVITY OF NEW HETEROCYCLIC COMPOUNDS DERIVED FROM 4-((1-(4-HYDROXYPHENYL) ETHYLIDENE) AMINO) BENZENESULFONAMIDE
...Show More Authors

The research included the preparation of cyclic compounds from thiazoles, imidazoles and oxazepines from the reaction of cyclization starting material that acts Schiff bases, which is a raw material in the formation of cyclic compounds from Schiff's(B1) by reaction of 4- aminobenzenesulfonylamide with 4-hydroxyacetophenone which can used to synthesized two lines. The first introducing the preparation of pyrazoles [B4, B5] from ester [B2], which derived to acid hydrazide[B3] with hydrazine hydrate and final pyrazoles obtained by the reaction with diethylmalonate and acetylacetone. The second including prepared the new 1,3-oxazepine1,5-dione derivatives[B6,B7,B8] from adding different anhydrides to the base[B1] as a seven membered ring ; te

... Show More
View Publication
Crossref
Publication Date
Thu Oct 25 2018
Journal Name
Al-nahrain Journal Of Science
Synthesis of some New 3-Substituted Heterocyclic Compounds Containing Bridgehead Nitrogen from 2-Amino Pyridine with Study Their Biological Activity
...Show More Authors

View Publication
Crossref
Publication Date
Sun Nov 10 2019
Journal Name
Journal Of Engineering And Applied Sciences
Fabrication and Properties of Ag<sub>2</sub>O/Si Heterojunction Solar Cell Pure and Doped (Sb, Sn and Se)
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Fri Jan 01 2010
Journal Name
Diala, Journal
Synthesis and characterization of ( L- proline ) amino acid with (Mn+2 , Fe+2 , Co+2 , Zn+2 and Cd+2 )
...Show More Authors

Preview PDF
Publication Date
Tue Jun 01 2021
Journal Name
Minar International Journal Of Applied Sciences And Technology
STRUCTURAL AND ELECTRICAL PROPERTIES OF (CDO)1-X (V2O5)X PREPARED BY PULSE LASER DEPOSITION TECHNIQUE FOR SOLAR CELL APPLICATIONS
...Show More Authors

In this work ,pure and doped(CdO)thin films with different concentration of V2O5x (0.0, 0.05, 0.1 ) wt.% have been prepared on glass substrate at room temperature using Pulse Laser Deposition technique(PLD).The focused Nd:YAG laser beam at 800 mJ with a frequency second radiation at 1064 nm (pulse width 9 ns) repetition frequency (6 Hz), for 500 laser pulses incident on the target surface At first ,The pellets of (CdO)1-x(V2O5)x at different V2O5 contents were sintered to a temperature of 773K for one hours.Then films of (CdO)1-x(V2O5)x have been prepared.The structure of the thin films was examined by using (XRD) analysis..Hall effect has been measured in orded to know the type of conductivity, Finally the solar cell and the effici

... Show More
View Publication
Crossref
Publication Date
Thu May 17 2012
Journal Name
Baghdad Science Journal
Synthesis and Spectral Studies of ZnII,CdII and HgII Complexes with 5-(2-Benzoic acid azo)-8-hydroxy quinoline Ligand
...Show More Authors

Coupling reaction of 2-amino benzoic acid with 8-hydroxy quinoline gave bidentate azo ligand. The prepared ligand has been identified by Microelemental Analysis,1HNMR,FT-IR and UV-Vis spectroscopic techniques. Treatment of the prepared ligand with the following metal ions (ZnII,CdII and HgII) in aqueous ethanol with a 1:2 M:L ratio and at optimum pH, yielded a series of neutral complexes of the general formula [M(L)2]. The prepared complexes have been characterized by using flame atomic absorption, (C.H.N) Analysis, FT-IR and UV-Vis spectroscopic methods as well as conductivity measurements. The nature of the complexes formed were studied following the mole ratio and continuous variation methods, Beer's law obeyed over a concentration range

... Show More
Preview PDF
Publication Date
Fri Jan 01 2021
Journal Name
Journal Of Mechanical Engineering Research And Developments
Fatigue life of welded joint improvement with various welding principles and shot peening process for AISI 1020 low carbon steel
...Show More Authors

Preview PDF
Scopus (1)
Scopus
Publication Date
Mon Aug 28 2023
Journal Name
Journal Of Planner And Development
Estimation of urban land price within holly cities by using integrated GIS-regression models: case study Al-Kufa city- Iraq
...Show More Authors

        Urban land price is the primary indicator of land development in urban areas. Land prices in holly cities have rapidly increased due to tourism and religious activities. Public agencies are usually facing challenges in managing land prices in religious areas. Therefore, they require developed models or tools to understand land prices within religious cities. Predicting land prices can efficiently retain future management and develop urban lands within religious cities. This study proposed a new methodology to predict urban land prices within holy cities. The methodology is based on two models, Linear Regression (LR) and Support Vector Regression (SVR), and nine variables (land price, land area,

... Show More
View Publication Preview PDF