Preferred Language
Articles
/
ijs-12350
Effect of Laser Surface Treatment on Physical Properties of Composite Material (Al-B4C)
...Show More Authors

This work study the effect of laser surface heat treatment on physical properties (green density, density after sintering, theoretical density and porosity)of a composite material of an Al powder as a matrix with different percentage of B4C powder as additive material. This work was done by two stages: First stage: Production the maincomposite material which is contain Al powder with grain size 24μm as a matrix and B4C powder with grain size 50μm as additive with different weight percentage (5%,10%,15%,20%,25%,30%), and the powders Maxined for suitable time 15min, after that the mixture compacted with 2ton and sintered at 550C0. Second stage: Laser surface treatment was done for the productive composite material after sintering by using pulse Nd: YAG laser with 1J energy, wave length 1064nm and pulse duration 100ns.Laser surface heat treatment was carried out with one pulse and two pulses respectively. Macrohardness of the composite material was measured after the sintering process and after the laser surface heat treatment with one pulse and two pulses, also photo-micrographies were taken for the specimens by using ordinary microscopic after each of sintering process and laser surface heat treatment. The results show that improvement of physical properties mentioned above and macrohardness after laser surface treatment with two pulses more than one pulse.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Jul 01 2018
Journal Name
Journal Of Educational And Psychological Researches
The relationship between critical thinking, epistemological beliefs, and learning strategies with the students’ academic performance
...Show More Authors

The present study was conducted to investigate the relationship between critical thinking, epistemological beliefs, and learning strategies with the academic performance of high school first-grade male and female students in Yazd. For this purpose, from among all first-grade students, as many as 250 students (130 females and 120 males) were selected by using multistage cluster sampling. The data needed were then collected through using California Critical Thinking Skills Test, Schommer's Epistemological Beliefs Questionnaire, Biggs’ Revised Two Factor Study Process Questionnaire. The findings indicated that there is a positive significant relationship between critical thinking and academic performance and achievement. Moreover, four fa

... Show More
View Publication Preview PDF
Publication Date
Sat Dec 01 2012
Journal Name
Iraqi Journal Of Physics
Elastic electron scattering from some 2s-1d shell nuclei
...Show More Authors

The charge density distributions (CDD) and the elastic electron
scattering form factors F(q) of the ground state for some even mass
nuclei in the 2s 1d shell ( Ne Mg Si 20 24 28 , , and S 32 ) nuclei have
been calculated based on the use of occupation numbers of the states
and the single particle wave functions of the harmonic oscillator
potential with size parameters chosen to reproduce the observed root
mean square charge radii for all considered nuclei. It is found that
introducing additional parameters, namely 1 , and , 2  which
reflect the difference of the occupation numbers of the states from
the prediction of the simple shell model leads to a remarkable
agreement between the calculated an

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 30 2014
Journal Name
Al-kindy College Medical Journal
Anal Fissure: Is it becoming a medical disorder? Review Article
...Show More Authors

An anal fissure which does not heal with conservative measures as sits baths and laxatives is a chronic anal fissure. Physiologically, it is the high resting tone of the internal anal sphincter that chiefly interferes with the healing process of these fissures. Until now, the gold standard treatment modality is surgery, either digital anal dilatation or lateral sphincterotomy. However, concerns have been raised about the incidence of faecal incontinence after surgery. Therefore, pharmacological means to treat chronic anal fissures have been explored. A Medline and pub med database search from 1986-2012 was conducted to perform a literature search for articles relating to the non-surgical treatment of chronic anal fissure. Pharmacological

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 30 2014
Journal Name
Al-kindy College Medical Journal
Anal Fissure: Is it becoming a medical disorder?
...Show More Authors

An anal fissure which does not heal with conservative measures as sits baths and laxatives is a chronic anal fissure. Physiologically, it is the high resting tone of the internal anal sphincter that chiefly interferes with the healing process of these fissures. Until now, the gold standard treatment modality is surgery, either digital anal dilatation or lateral sphincterotomy. However, concerns have been raised about the incidence of faecal incontinence after surgery. Therefore, pharmacological means to treat chronic anal fissures have been explored.A Medline and pub med database search from 1986-2012 was conducted to perform a literature search for articles relating to the non-surgical treatment of chronic anal fissure.Pharmacological s

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 30 2014
Journal Name
Al-kindy College Medical Journal
Anal Fissure: Is it becoming a medical disorder?
...Show More Authors

An anal fissure which does not heal with conservative measures as sits baths and laxatives is a chronic anal fissure. Physiologically, it is the high resting tone of the internal anal sphincter that chiefly interferes with the healing process of these fissures. Until now, the gold standard treatment modality is surgery, either digital anal dilatation or lateral sphincterotomy. However, concerns have been raised about the incidence of faecal incontinence after surgery. Therefore, pharmacological means to treat chronic anal fissures have been explored.A Medline and pub med database search from 1986-2012 was conducted to perform a literature search for articles relating to the non-surgical treatment of chronic anal fissure.Pharmacological s

... Show More
View Publication Preview PDF
Publication Date
Sun Oct 02 2022
Journal Name
Al-manhaj
Mathematical Statistics - Second Edition
...Show More Authors

This Book is the second edition that intended to be textbook studied for undergraduate/ postgraduate course in mathematical statistics. In order to achieve the goals of the book, it is divided into the following chapters. Chapter One introduces events and probability review. Chapter Two devotes to random variables in their two types: discrete and continuous with definitions of probability mass function, probability density function and cumulative distribution function as well. Chapter Three discusses mathematical expectation with its special types such as: moments, moment generating function and other related topics. Chapter Four deals with some special discrete distributions: (Discrete Uniform, Bernoulli, Binomial, Poisson, Geometric, Neg

... Show More
Preview PDF
Publication Date
Mon Nov 01 2010
Journal Name
Al-nahrain Journal Of Science
Chemical Elements Diffusion in the Solar Interior
...Show More Authors

Publication Date
Sun Jul 02 2023
Journal Name
Iraqi Journal Of Science
Elastic Electron Scattering form Factors for Odd-A 2s-1d Shell Nuclei
...Show More Authors

The charge density distributions (CDD) and the elastic electron scattering form
factors F(q) of the ground state for some odd mass nuclei in the 2s 1d shell, such
as K Mg Al Si 19 25 27 29 , , , and P 31
have been calculated based on the use of
occupation numbers of the states and the single particle wave functions of the
harmonic oscillator potential with size parameters chosen to reproduce the observed
root mean square charge radii for all considered nuclei. It is found that introducing
additional parameters, namely; 1  , and , 2  which reflect the difference of the
occupation numbers of the states from the prediction of the simple shell model leads
to very good agreement between the calculated an

... Show More
View Publication Preview PDF
Publication Date
Sun Oct 22 2023
Journal Name
Iraqi Journal Of Science
Elastic Electron Scattering form Factors for Odd-A 2s-1d Shell Nuclei
...Show More Authors

The charge density distributions (CDD) and the elastic electron scattering form
factors F(q) of the ground state for some odd mass nuclei in the 2s 1d shell, such
as K Mg Al Si 19 25 27 29 , , , and P 31
have been calculated based on the use of
occupation numbers of the states and the single particle wave functions of the
harmonic oscillator potential with size parameters chosen to reproduce the observed
root mean square charge radii for all considered nuclei. It is found that introducing
additional parameters, namely; 1  , and , 2  which reflect the difference of the
occupation numbers of the states from the prediction of the simple shell model leads
to very good agreement between the calculated an

... Show More
View Publication Preview PDF