Preferred Language
Articles
/
alkej-71
Studying the Effect of Addition Particles of Alumina (Al2O3) and Zirconia (ZrO2), on Some Mechanical Properties for Matrix Composites (Al-Si-Mg) Alloy
...Show More Authors

This study is concerned with the effect of adding two kinds of ceramic materials on the mechanical properties of (Al-7%Si- 0.3%Mg) alloy, which are zirconia with particle size (20μm > P.S ≥ 0.1μm) and alumina with particle size (20μm > P.S ≥ 0.1μm) and adding them to the alloy with weight ratios (0.2, 0.4, 0.6, 0.8 and 1%). Stirring casting method has been used to make composite material by using vortex technique which is used to pull the particles to inside the melted metals and distributed them homogenously.

After that solution treatment was done to the samples at (520ºC) and artificial ageing at (170ºC) in different times, it has been noticed that the values of hardness is increased with the aging time of the original alloy and reached its highest value after (8hr).

Mechanical tests were done to the original alloy and the composite material at the maximum hardness value and represented by tensile, hardness, and wear tests. It was found that the hardness value is increased with increment of the amount of added particles; also the increment in the hardness of the alloy which is reinforced with alumina is more than that reinforced with zirconia.

Regarding the tensile test, results show that the strength and yield resistance of the composite material are more than that in the original alloy and these values are increased with increasing the amount of the added particles and they reached maximum values at (0.6%). Then they are decreased but these values remain at higher values than those in the original alloy. However, the ductility is decreased as compared with the original alloy and this decrement was more obvious with the increasing amount of the added particles. The increment of strength and yield resistance of the alloy reinforced by alumina was higher than that reinforced with zirconia, while the ductility of the alloy reinforced by zirconia was higher than that happened by the addition of alumina. Also zirconia and alumina addition to the original alloy decreased the wear rate, and the decrement would be more with the increased amount of adding particles. In addition the wear resistance of the alloy reinforced with alumina was larger than that reinforced with zirconia. X-rays testing proved that secondary phase (AlFeSi) appeared in both original alloy and the composite material. While heat treatment led to the appearance of phases (Mg2Al) and (Mg2Si) in original alloy. This was led to obvious improvement in the mechanical properties in addition to appearance ceramic particles in the microstructure of the composite material.

This structure somewhat homogenous has fine grains as compared with large grains in the microstructure of the original alloy. .        

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Sep 01 2023
Journal Name
Journal Of Building Engineering
Discharge performance assessment of a vertical double-pipe latent heat storage unit equipped with circular Y-shaped fins
...Show More Authors

This paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the sol

... Show More
View Publication
Scopus (63)
Crossref (19)
Scopus Crossref
Publication Date
Fri Apr 07 2017
Journal Name
Oncology Letters
AURKA mRNA expression is an independent predictor of poor prognosis in patients with non-small cell lung cancer
...Show More Authors

View Publication
Scopus (40)
Crossref (33)
Scopus Clarivate Crossref
Publication Date
Wed Jan 02 2019
Journal Name
Journal Of The College Of Languages (jcl)
Methods of Teaching Conversation in Russian Students Speaking Arabic: Методы преподавания говорения на русском языке в арабской аудитории
...Show More Authors

      This paper tackles methods of teaching conversation in Russian to students speaking Arabic. It analyses the differences between the two languages, as well as the difficulties and major errors faced by Arabic speakers studying Russian. Particularly, it looks at the difficulty of transforming spoken language. Finally, the paper suggests ways for teaching spoken language and treating the reasons behind making errors.

Аннотация

          Данная статья рассматривает методы преподавания говорения на русском языке для носителей арабского яз

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Certain Assessment of Using MWCNT Nps in Drilling Fluid to Mitigate Stick-Slip Problem during Drilling Operation System
...Show More Authors

   Stick- slip is the continuous stopping& release of the Bit/BHA due to the irregular down-hole rotation prompted by the existing relationship between the friction torque and the torque applied from the surface to free the bit.

   Friction coefficient between BHA and wellbore is the main player of stick slip amount, which can be mitigated by support a good lubricators as additives in drilling mud.

   Mathematical (or empirical) solves should be done through adjusting all parameters which supposed to reduce stick- slip as low as possible using different models, one of the main parameters is drilling mud. As per Nanoparticles drilling fluid is a new technology that offers high performance

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Wed Aug 30 2023
Journal Name
Al-kindy College Medical Journal
Assessment of Thyroid Functions in Multiple Sclerosis Patients Treated with Disease Modifying Therapies: Thyroid Functions in Multiple Sclerosis
...Show More Authors

Background:

Multiple sclerosis is a chronic disease believed to be the result of autoimmune disorders of the central nervous system, characterised by inflammation, demyelination, and axonal transection, affecting primarily young adults. Disease modifying therapies have become widely used, and the rapid development of these drugs highlighted the need to update our knowledge on their short- and long-term safety profile.

Objective:

The study aim is to evaluate the impact of disease-modifying treatments on thyroid functions and thyroid autoantibodies with subsequent effects on the outcome of the disease.

Materials and Methods:

A retro prospective study

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (4)
Scopus Crossref
Publication Date
Mon Apr 10 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Adherence to American Society of Health-System Pharmacists Surgical Antibiotic Prophylaxis Guideline in Medical City Teaching Hospitals/Baghdad
...Show More Authors

Surgical site infections are the second most common type of adverse events occurring in hospitalized patients. Surgical antibiotic prophylaxis refers to the use of preoperative and postoperative antibiotics to decrease the incidence of postoperative wound infections. The objective of this study was to evaluate the antibiotic administration pattern for surgical antibiotic prophylaxis and the adherence to American Society of Health-System Pharmacists surgical antibiotic prophylaxis guideline in Medical City Teaching Hospitals/Baghdad. The medical records of one hundred patients who underwent elective surgical procedures were reviewed. Adherence to the recommendations of American society of health‑system pharmacists guideline was ass

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
Maternal knowledge related to anemia during pregnancy among a sample of mothers attending Primary Health Care centers. Baghdad.
...Show More Authors

Background: Anaemia is a major public health concern and is one of the most prevalent health issue in women within reproductive age group.

Objective: to assess maternal knowledge related to anaemia during pregnancy.

Type of the study: A cross –sectional study.

Method: The study including 200 mothers who attended selected primary health care centres, Baghdad during November and December 2015, they completed a previously prepared questionnaire coveringsocio-demographic characteristics and knowledge regarding anaemia in 4 main domains. The responses were analysed by using frequency, percentage and percent score for each statement a

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sun Mar 25 2018
Journal Name
Journal Of Education College Wasit University
A Cognitive Linguistic Study of Silence/Pause-Based Incongruities in Selected Instances from Mind Your Language's Sitcom Series
...Show More Authors

The present research aims at: First, to examine the reasons behind using silence/pause-based unintentional incongruities in selected instances from the British Sitcom Mind Your Language; second, to explore specifically the types of silence/pause-based unintentional incongruities and the different facial gestures that accompany each of these types. To meet these two objectives, the analysis will be theoretically and conceptually-based, respectively. Conclusions, as far as the first objective is concerned, have shown that silence can be used to reflect: the sense of being inattentive; lack of understanding; being unfamiliar with what one hears; the time needed for thinking and associating, and the act of hiding one's nervousness, etc.

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Jun 01 2020
Journal Name
Journal Of The College Of Languages (jcl)
Literature and Novel: Classical novel in comparison to New Novel By Alain Robbe - Grillet: L'Art et le Roman: Le Roman Traditionnel Face au Nouveau Roman Alain Robe- Grillet
...Show More Authors

Modern French novel has gained a distinctive status in the history of French literature during the first half of the twentieth century. This is due to many factors including the new literary descriptive objective style adopted by novelists like Alain Robbe – Grillet that  has long been regarded as the outstanding writer of the nouveau roman, as well as its major spokesman, a representative writer and a leading theoretician of the new novel that has broken the classical rules of the one hero and evolved, through questioning the relationship of man and the world and  reevaluating the limits of contemporary fiction , into  creating a new form of narrative.

Résumé:

En vue de résu

... Show More
View Publication Preview PDF
Publication Date
Tue Mar 01 2022
Journal Name
Iraqi Journal Of Applied Physics
Fabrication of Solid Random Gain Media in Visible Region From Rhodamine Dye Solutions Containing Highly-Pure Titanium Dioxide Nanoparticles
...Show More Authors

In this work, solid random gain media were fabricated from laser dye solutions containing nanoparticles as scattering centers. Two different rhodamine dyes (123 and 6G) were used to host the highly-pure titanium dioxide nanoparticles to form the random gain media. The spectroscopic characteristics (mainly fluorescence) of these media were determined and studied. These random gain media showed laser emission in the visible region of electromagnetic spectrum. Fluorescence characteristics can be controlled to few nanometers by adjusting the characteristics of the host and nanoparticles as well as the preparation conditions of the samples. Emission of narrow linewidth (3nm) and high intensity in the visible region (533-537nm) was obtained.

View Publication Preview PDF