Preferred Language
Articles
/
bsj-7584
Performance Evaluation of a Triple Concentric Tube Heat Exchanger Using Deionized Water and Oil-40
...Show More Authors

This study examines experimentally the performance of a horizontal triple concentric tube heat exchanger TCTHE made of copper metal using water as cooling fluid and oil-40 as hot fluid. Hot fluid enters the inner annular tube of the TCTHE in a direction at a temperature of 50, 60 and 70 oC and a flow rate of 20 l/hr. On the other hand, the cooling fluid enters the inner tube and the outer annular tube in the reverse direction (counter current flow) at a temperature of 25 oC and flow rates of 10, 15, 20, 25, 30 and 35 l/hr. The TCTHE is composed of three copper tubes with outer diameters of 34.925 mm, 22.25 mm, and 9.525 mm, and thicknesses of 1.27 mm, 1.143 mm, and 0.762 mm, respectively. TCTHE tube's length was 670 mm. Nusselt number, overall heat transfer coefficient, convective heat transfer coefficient (CHTC), friction factor and pressure drop were measured from the obtained experimental results and plotted in graphs against Reynold number and volumetric flow rate of water. These parameters appeared good results in the cooling process. Nusselt numbers increased linearly with DIW flow rate for both C1 and C2 reaching maximum values of 38.25 and 14.64 respectively. CHTC increased linearly with the DIW flow rate for both C1 and C2 reaching maximum values of 2934.3 and 871.7 respectively. Overall heat transfer coefficient of DIW reached maximum values of 296.36 and 251.4 at 35 l/hr for C1 and C2, respectively. Friction factor DIW in C1 and C2 decreased with the volumetric flow rate increases, reaching minimum values of 0.04 and 0.25 respectively. Pressure drop of DIW increased linearly with flow rate reaching maximum values of 81.4 and 4.31 for C1 and C2 respectively. This in turn leads to reduced TCTHE length and size leading to a decrease in the construction cost of the heat exchanger.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The Green Regulatory Tapes and Their Reflections on the Job Development - A Study for the Sample of Employees in the Nineveh Directorate for Bridges & Roads
...Show More Authors

The performance of job effectively requires narrowing the meaningful routine activities and attempting employing the job procedures in favor of public welfare through adding the green impact as well as removing them from the red tapes which reflect the firmness of procedures, to enable the job parties to make their job independently, and pushing them to gain priority in the competition layer. This is not attaining easily amidst the regulatory problems expressed by the complication of procedures, the thing which make identifying the problem of the study through the following question:

Should we make the complex of procedures and their firmness a way to adopt the idea of the green regulatory tapes supportin

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 10 2015
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
New Schiff Base Derived From Folic Acid and 3- Aminoacetophenone and its Metal Complexes with Some Transition Metals and Evaluation of Their Biological Activity
...Show More Authors

The ligand [Potassium (E)-(4-(((2-((1-(3-aminophenyl) ethylidene) amino)-4-oxo-1,4- dihydropteridin-6-yl) methyl) amino)benzoyl)-L-glutamate] was prepared from the condensation reaction of folic acid with (3-aminoacetophenone) through Schiff reaction to give a new Schiff base ligand [H2L]. The ligand [H2L] was characterized by elemental analysis CHN, atomic absorption (A.A), (FT-I.R.), (U.V.-Vis), TLC, E.S. mass (for spectroscopes), molar conductance, and melting point. The new Schiff base ligand [H2L], reacts with Mn(II), Co(II), Ni(II), Cu(II), Cr(III) and Cd(II) metal ions and (2-aminophenol), (metal : derivative ligand : 2-aminophenol) to give a series of new mixed complexes in the general formula:- K3[M2(HL)(HA)2], (where M=Mn(II) and

... Show More
Publication Date
Wed Nov 22 2017
Journal Name
Farm Machinery And Processes Management In Sustainable Agriculture, Ix International Scientific Symposium
INFLUENCE OF PHYSICAL PROPERTIES OF WATER-ADJUVANT MIXTURE ON THE DROPLET STAINS DEPOSITING ON AN ARTIFICIAL TARGET
...Show More Authors

View Publication
Clarivate Crossref
Publication Date
Wed Dec 01 2010
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FIRST RECORD OF FIVE NEMATODE SPECIES IN SOME WATER BIRDS FROM AL-HAMMAR MARSH, SOUTH OF IRAQ
...Show More Authors

Parasitological investigation of piscivorous birds in Al-Hammar marsh south of Iraq during December-February 2004 and December 2005 were revealed that water birds infected with five nematode species, which belong to three different superfamilies, Desmidocercella numidica (Seurat, 1920) (Superfamily: Aproctoidea) from three piscivorous birds including Grey heron Ardea cinerea, Bittern Botaurusstellaris, and small white heron Ardeola ralloides; Avioserpens sp. 1 and Avioserpens sp. 2 (Superfamily: Dracunculoidea) from small bittern Ixobrychus minutus and black glossy ibis Plegadisfalcinellus respectively; Baruscapillaria sp. and Baruscapillarinae gen. sp. (Sup

... Show More
View Publication Preview PDF
Publication Date
Sat Sep 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of knowledge workers characteristics on knowledge acquision “Survey Study of the views of a sample of engineers and technicians in the Directorate of Electricity In the city of Sulaymaniyah
...Show More Authors

Purpose: The research aims to diagnose the current availability of knowledge workers characteristics and the role of these characteristics in knowledge acquision in the city of Sulaimaniya Directorate of Electricity, and to identify the differences between personal and occupational characteristics of a sample of research and its impact on the availability of such properties.

Design/methodology/approach :to achieve the objectives of the research questionnaire was developed especially for it and then distributed to a sample of engineers and technicians working in the Directorate of Electricity city of Sulaimaniya, where the sample of the research (52) respondents.

Findings:  the most important conclusions reached

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
Dimensions of binding and non-binding social responsibility and its relationship to organizational performance / Field Study in telecommunications companies in the Republic of yemen
...Show More Authors

The study aims at measuring the dimensions of binding and non-binding social responsibility and its relation to the organizational performance in telecommunication companies in the Republic of Yemen using analytical descriptive approach and questionnaire as a main tool for data collection and comprehensive inventory method.

It has been found  that there is a positive effect and significant moral relation between social responsibility with its binding and non-binding dimensions  and the organizational performance of telecommunication companies in the Republic of Yemen at a level of significance below (0.05). It has also been found that the correlation between the non-binding social responsibilit

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Sep 01 2018
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Functional rotation and its impact on tax performance: Applied research in the General Authority for Taxation
...Show More Authors

The research aimed at finding out the effect of functional rotation on the tax performance of the employees of the General Authority for Taxes through the five-meter questionnaire prepared according to the required data. The data obtained from the research sample were analyzed. The results showed a significant effect of recycling In the tax performance, and this is evident from the proportion of his contribution to the interpretation of the total variation, which is a good indicator of the impact of functional rotation in the performance of the body sample research.

View Publication Preview PDF
Crossref
Publication Date
Mon Mar 28 2022
Journal Name
Journal Of Physical Education
The Effect of Using a Teaching Aid on Learning Backswing to Handstand on Rings in Youth Artistic Gymnastics
...Show More Authors

               The research aimed at designing a teaching aid for learning backswing into handstand as well as identifying its effect on learning skill performance. The researchers hypothesized statistical differences between pre and post-tests in favor of the research group. They used the experimental method on six (13 – 16) year–old Baghdad club gymnasts. The researchers used the one group design in which all players perform pretests followed by special tests on the teaching aid than are tested posttests. The researchers conclude that the teaching aid positively affected learning the skill as well as the teaching aid was very good and endured the performance of all gymnasts. The researcher recommended making simi

... Show More
Crossref
Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
A Comparison of Parameters Estimation Methods for the Negative Binomial Regression Model under Multicollinearity Problem by Using Simulation
...Show More Authors

This study discussed a biased estimator of the Negative Binomial Regression model known as (Liu Estimator), This estimate was used to reduce variance and overcome the problem Multicollinearity between explanatory variables, Some estimates were used such as Ridge Regression and Maximum Likelihood Estimators, This research aims at the theoretical comparisons between the new estimator (Liu Estimator) and the estimators

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Chemical Industry And Chemical Engineering Quarterly
Optimization of dye adsorption process for Albizia lebbeck pods as a biomass using central composite rotatable design model
...Show More Authors

Albizia lebbeck biomass was used as an adsorbent material in the present study to remove methyl red dye from an aqueous solution. A central composite rotatable design model was used to predict the dye removal efficiency. The optimization was accomplished under a temperature and mixing control system (37?C) with different particle size of 300 and 600 ?m. Highest adsorption efficiencies were obtained at lower dye concentrations and lower weight of adsorbent. The adsorption time, more than 48 h, was found to have a negative effect on the removal efficiency due to secondary metabolites compounds. However, the adsorption time was found to have a positive effect at high dye concentrations and high adsorbent weight. The colour removal effi

... Show More
View Publication
Scopus (14)
Crossref (12)
Scopus Clarivate Crossref