Preferred Language
Articles
/
alkej-409
Enhancement of Heat Exchanger Performance by Using Dimpled Tube
...Show More Authors

The enhancement of heat exchanger performance was investigated using dimpled tubes tested at different Reynolds numbers, in the present work four types of dimpled tubes with a specified configuration manufactured, tested and then compared performance with the smooth tube and other passive techniques performance. Two dimpled arrangements along the tube were investigated, these are inline and staggered at constant pitch ratio X/d=4, the test results showed that Nusselts number (heat transfer) of the staggered array is higher than the inline array by 13%.  The effect of different depths of the dimple (14.5 mm and 18.5 mm) has been also investigated; a tube with large dimple diameter enhanced the Nusselts number by about 25% for the range of Reynolds number between 4000- 20000. The overall enhancement ratio was used to differentiate the passive technique and comparison of different configurations for the technique itself, the result depicted that the 10 mm dimple diameter with a pitch ratio of X/d= 4 gives better performance than the static mixer and twisted tape techniques. The overall enhancement ratio of the 10 mm dimple diameter is varied from (1.21 to 1.65) that means good performance for a range of Reynolds numbers (4000-20000). This indicates that 21- 65 % of heat transfer area can be saved at the same pumping power compared with the smooth tube heat exchanger. 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Mar 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Studies on the Benification of Fine Solids by Forth Flotation
...Show More Authors

In this paper, the experiments were carried out in laboratory flotation cell treating solid fines. The effect of variables such as collector oil dosage, pine oil dosage and solid content of the feed slurry have been investigated on the flotation characteristics of low rank coal. Attempts have also been made to develop some empirical Eq. to predict the yield and ash content of concentrate with the operating variables, solids concentration, collector oil dosage, and pine oil dosage, to estimate the recovery at any operating conditions. The calculated results obtained from regression equation by correlating the variables with the yield and ash content of concentrate have been compared to study whether calculated values match closely with th

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 09 2019
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Formulation and Evaluation of Silymarin Microcrystals by In- Situ Micronization Technique
...Show More Authors

Silymarin (SM) is a plant extract obtained from Silybum marianum( milk thistle) . It is class II type drug according to  Biopharmaceutics Classification System with low bioavailability due to its low solubility.

Micro/nanonization during crystallization, surface modification and crystal structure modification may improve the dissolution rate of poorly water-soluble drugs.

The aim of this study was to increase the water solubility and dissolution rate of SM by in-situ micronization using solvent change either by stirring or ultrasonic method. Stabilizers like Gelatin, PVP-K30, HPMC15, Pulullan were used to stabilize the prepared ultrafine crystals. Effect of type and concentration of hydrophilic polymer, solv

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (3)
Scopus Crossref
Publication Date
Thu Sep 03 2009
Journal Name
Engineering And Technology Journal
Study on the properties of composite materials produced by centrifugal casting
...Show More Authors

سمير خلف فياض * و محسن طالب د.نوال عزت عبد اللطيف*, مجلة الهندسة والتكنولوجيا, 2010

View Publication Preview PDF
Publication Date
Tue Jan 17 2023
Journal Name
Karbala International Journal Of Modern Science
Biofunctionalization of polyetheretherketone implant material by bone-forming peptide-2 immobilization
...Show More Authors

Polyetheretherketone (PEEK) has favorable biomechanical properties to be used as an implant material. Unfortunately, it is hydrophobic and does not promote cellular adhesion, which could result in poor integration with bone tissue. Bio-functionalization of PEEK surface with osteogenic peptides derived from bone extracellular matrix proteins is an exciting approach to encourage bone formation around the implant. In the current study, bone-forming peptide-2 was immobilized on PEEK surface using two different methods, using dopamine and a diglycidyl ether as conjugate compounds, respectively. Peptide quantification test revealed that the two strategies resulted in the most amount of peptides were attached with 0.5 mM concentration and no furth

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (5)
Scopus Crossref
Publication Date
Thu Jul 01 2021
Journal Name
Journal Of Applied Sciences And Nanotechnology
Homogeneity of Lithium Metasilicate-Copper Oxide Glass-Ceramics by Weibull Modulus
...Show More Authors

View Publication
Crossref (1)
Crossref
Publication Date
Mon Mar 03 2014
Journal Name
Journal Of Al-nahrain University
Adsorption of Ciprofloxacin Hydrochloride from Aqueous Solution by Iraqi Porcelinaite Adsorbent
...Show More Authors

Pharmaceuticals are widely distributed in different applications and also released into the environment. Adsorption of Ciprofloxacin HCl (CIPH) on Porcelinaite was studied at ambient conditions. The adsorption isotherms can be well described using the Freundlich and Temkin equations. The pH of the solution influences significantly the adsorption capacity of Porcelinaite, the adsorption of CIPH increased from the initial pH 1.3 and then decreased over the pH rang of 3.8-9. The adsorption is sensitive to the change in ionic Strength, which indicate that electrostatic attraction is a significant mechanism for sorption process. The enthalpy change (ΔH) for the adsorption of CIPH onto Porcelinaite signifies an endothermic adsorption. The ΔG va

... Show More
Preview PDF
Publication Date
Tue Nov 01 2022
Journal Name
Journal Of Engineering
Study The Impact of Geopolymer Mortar Reinforced by Micro Steel Fibers
...Show More Authors

In this research, geopolymer mortar had to be designed with 50% to 50% slag and fly ash with and without 1% micro steel fiber at curing temperature of 240℃. The molarity of alkaline solution adjusted with 12 molar sodium hydroxid to sodium silicate was 2 to 1, reaspectivly. The heat of curing increased the geopolymerization proceses of geoplymer mortar, which led to increasing strength, giving the best result and early curing age. The heat was applied for two days by four hours each day. It was discovered in the impact test that the value first crack of each mix was somewhat similar, but the failure increased 72%  for the mixture that did not contain fiber. For the energy observation results it was shown that the mixt

... Show More
View Publication Preview PDF
Crossref (3)
Crossref
Publication Date
Sun Nov 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Emissions Investigating of Carbon Dioxide Generated by the Iraqi Cement Industry
...Show More Authors
Abstract<p>The most used material in the world after water is concrete, which depends mainly on its manufacture of cement leading to the emission of carbon dioxide (CO<sub>2</sub>), flying dust, and other greenhouse gasses (GHGs) resulting in pollution of the atmosphere. The emission of CO<sub>2</sub> from cement production is approximately 5% of the global anthropogenic CO<sub>2</sub>. This research focuses on investigating the amount of CO<sub>2</sub> emission from the Iraqi General Cement Company plants includes the cement factories of Kirkuk, Al-Qa’em, Fallujah, and Kubaisa, using the GHGs Protocol Measures Program (specifically cement based-method).</p> ... Show More
View Publication
Scopus (24)
Crossref (17)
Scopus Crossref
Publication Date
Sat Feb 01 2020
Journal Name
Civil Engineering Journal
Assessment of Moisture Susceptibility for Asphalt Mixtures Modified by Carbon Fibers
...Show More Authors

Moisture induced damage in asphaltic pavement might be considered as a serious defect that contributed to growth other distresses such as permanent deformation and fatigue cracking. This paper work aimed through an experimental effort to assess the behaviour of asphaltic mixtures that fabricated by incorporating several dosages of carbon fiber in regard to the resistance potential of harmful effect of moisture in pavement. Laboratory tests were performed on specimens containing fiber with different lengths and contents. These tests are: Marshall Test, the indirect tensile test and the index of retained strength. The optimum asphalt contents were determined based on the Marshall method. The preparation of asphaltic mixtures involved

... Show More
Scopus (26)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Sat Dec 30 2017
Journal Name
Al-khwarizmi Engineering Journal
Welding of Low Alloy Steel DIN 15Mo3 by MIG/MAG Spot
...Show More Authors

This research deals with the effects of welding variables using MIG/MAG spot by using Argon (Ar) gas and CO2 to show their effect on the mechanical characteristics and microstructure of low alloy steel type DIN15Mo3 and determine the optimum condition for the process of welding ; current & time. The results show the possibility of using CO2 and also Ar in low alloy steel welding with a little decrease in the shear force of not more than 13% for 4mm thickness and time 2sec. The shear force increased when using Ar instead of CO2 to be , The shear force reach 36KN when using Ar at 2mm thickness  time of 8 sec and current of 220 Amp. , when used CO2 instead of Ar d

... Show More
View Publication Preview PDF