Preferred Language
Articles
/
eReaCpEBVTCNdQwCrJJ7
Physical principles of laser–material interaction regimes for laser machining processes
...Show More Authors

Lasers, with their unique characteristics in terms of excellent beam quality, especially directionality and coherency, make them the solution that is key for many processes that require high precision. Lasers have good susceptibility to integrate with automated systems, which provides high flexibility to reach difficult zones. In addition, as a processing tool, a laser can be considered as a contact-free tool of precise tip that became attractive for high precision machining at the micro and nanoscales for different materials. All of the above advantages may be not enough unless the laser technician/engineer has enough knowledge about the mechanism of interaction between the laser light with the processed material. Several sequential phenomena occur when an intense laser beam is incident on the surface of a material. Heating, melting, vaporization and plasma formation are present in the normal interaction of an intense laser beam with matter. This may be followed by additional events such as acoustic and optical emissions, structure shockwaves, thermal effects, structural defects and residual stresses. The process is affected by a lot of variables that can transfer the interaction towards extremely different behavior in terms of colder and fewer side-effect interactions, which yield precise features for the processed material. The most crucial variables are the time scale of interaction and laser wavelength with respect to the properties of the processed material undertaken as well as the laser fluence. The objective of this chapter is to introduce the fundamentals of physical and mathematical concepts of laser and matter interaction and its dependency on different time scale regimes. Interaction with a short and ultra-short laser pulse has attracted a significant amount of interest in industry due to its huge impact in micro-/nanomachining applications.

Crossref
View Publication
Publication Date
Sun Jan 01 2017
Journal Name
Engineering And Technology Journal
Study of the Diffusion Coefficient and Hardness for a Composite Material when Immersed in Different Solutions Polymer
...Show More Authors

View Publication
Crossref (1)
Crossref
Publication Date
Wed Sep 29 2021
Journal Name
College Of Islamic Sciences
The provisions of the epidemic in jurisprudence and its principles The (Covid-19) epidemic is a model
...Show More Authors

Abstract

Epidemics that afflict humankind are descending renewed, plaguing them in the place and time they spread.

- The epidemic affects individuals and the movement of societies, and its treatment requires dealing with it according to Sharia, taking into account the current data and developments.

- Integrative jurisprudence: it is intended to know the practical legal rulings deduced from the combination of evidence of two or more sciences related to one topic related to it, and among these calamities is the Corona Covid-19 pandemic.

 - It is permissible to use sterile materials that contain a percentage of alcohol in sterilizing hands and fogging places, including mosques.

T

... Show More
View Publication Preview PDF
Publication Date
Wed Jun 29 2022
Journal Name
College Of Islamic Sciences
Principles of war and jihad to protect the environment and civilians in times of war in Islamic Sharia
...Show More Authors

The use of destructive weapons in wars without restrictions and controls, which eat green and dry land, pollute the environment and cause genocide, has become the problem of the times.

International conventions for the protection of the environment during armed conflicts are characterized by generality, ambiguity, and open to interpretation by the participating states in the agreement, and each state interprets these texts to serve its interests, but the Islamic Sharia stipulates the prohibition of the use of these comprehensive destructive weapons in an unambiguous manner, As stated in the Holy Quran:

                

... Show More
View Publication Preview PDF
Publication Date
Tue May 16 2023
Journal Name
Political Sciences Journal
Institutional Reality Construction: Principles of its Construction and Functions of Language in its Production; Diplomacy as a Model
...Show More Authors

This study aims to answer a significant problem of social sciences and philosophy: How do we construct an institutional reality such as diplomacy with an objective recognizable existence? The study assumes that the ability to build institutional reality is based on our biological capacity, as it takes different forms in all the institutions we construct. The study takes the theory of the American philosopher John Searle as an approach to examining the assumption. The study sums up important findings; cultures, although they share the biological capacity on which they produce institutional realities, differ in the form of the value standards on which the institutional realities are based. The study recommends the need of Arab social resea

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Sep 30 2022
Journal Name
College Of Islamic Sciences
Principles of war and jihad to protect the environment and civilians in times of war in Islamic Sharia
...Show More Authors

Research summary

Islam protects the environment and civilians in peace and war, and in international humanitarian law protection of the environment and civilians in international conflicts only. As for wars and internal conflicts, it is not within the jurisdiction of international humanitarian law. In Islamic law, the principles of protecting the environment and civilians are fixed in all wars and conflicts, whether internal or external, local. or international.

Islam laid down moral principles in war, including:

- Preserving the environment and avoiding corruption in the land by burning trees and killing animals unnecessarily.

- Not to be exposed to non-combatants, including women, boys, the elderly, the disa

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 20 2019
Journal Name
Baghdad Science Journal
Teen-Computer Interaction: Building a Conceptual Model with Thoughts- Emotion-Behaviour
...Show More Authors

Teen-Computer Interaction (TeenCI) stands in an infant phase and emerging in positive path. Compared to Human-Computer Interaction (generally dedicated to adult) and Child-Computer Interaction, TeenCI gets less interest in terms of research efforts and publications. This has revealed extensive prospects for researchers to explore and contribute in the region of computer design and evaluation for teen, in specific. As a subclass of HCI and a complementary for CCI, TeenCI that tolerates teen group, should be taken significant concern in the sense of its context, nature, development, characteristics and architecture. This paper tends to discover teen’s emotion contribution as the first attempt towards building a conceptual model for TeenC

... Show More
View Publication Preview PDF
Clarivate Crossref
Publication Date
Sun Mar 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Preparation of Polyvinyl Alcohol from Local Raw Material
...Show More Authors

Polyvinyl alcohol, (PVA) was prepared using polyvinyl acetate emulsion (manufactured by Al-Jihad factory,
That-Al-Sawary Company) as a local raw material. In this investigation, polyvinyl acetate emulsion was converted to
solid form by coagulation the polymer from its emulsion using sodium sulphate salt as coagulant aid, then alcoholyzed
the solid polyvinyl acetate in methanol using sodium hydroxide as catalyst, polyvinyl alcohol produced by this method is
a dry, white to yellow powder.
Three affecting variables on the degree of hydrolysis of PVA were studied, these variable are Catalyst to
polymer weight ratio in the range of 0.01 – 0.06, reaction time in the range of 20 – 90 min, and reaction temperature in
the

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 03 2020
Journal Name
Civileng
Evaluation of Concrete Material Properties at Early Age
...Show More Authors

This article investigates the development of the following material properties of concrete with time: compressive strength, tensile strength, modulus of elasticity, and fracture energy. These properties were determined at seven different hydration ages (18 h, 30 h, 48 h, 72 h, 7 days, 14 days, 28 days) for four pure cement concrete mixes totaling 336 specimens tested throughout the study. Experimental data obtained were used to assess the relationship of the above properties with the concrete compressive strength and how these relationships are affected with age. Further, this study investigates prediction models available in literature and recommendations are made for models that are found suitable for application to early age conc

... Show More
View Publication
Crossref (19)
Crossref
Publication Date
Wed Jan 10 2018
Journal Name
Al–bahith Al–a'alami
Quality standards and innovation in television production production processes in various fields
...Show More Authors

And the necessity for the progress of modern societies Because the scientific and objective characteristics that characterize modern societies and distinguish them from traditional societies, Is represented by the extent of its innovative achievements in the theoretical, applied and material scientific and spiritual fields. It should be noted that quality and innovation in modern societies is based on two main pillars, Standard measures for measuring and evaluating innovations to achieve their high quality, And the dissemination of the culture of innovation to spread awareness of the importance and conditions of success, and this is done by the advanced industrial countries, However, despite the great disparity between developed industri

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Sep 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
USING ALUMINUM REFUSE AS A COAGULANT IN THE COAGULATION AND FLIOCCULATION PROCESSES
...Show More Authors

The present work aims to study the efficiency of using aluminum refuse, which is available locally (after dissolving it in sodium hydroxide), with different coagulants like alum [Al2 (SO4)3.18H2O], Ferric chloride FeCl3 and polyaluminum chloride (PACl) to improve the quality of water. The results showed that using this coagulant in the flocculation process gave high results in the removal of turbidity as well as improving the quality of water by precipitating a great deal of ions causing hardness. From the experimental results of the Jar test, the optimum alum dosages are (25, 50 and 70 ppm), ferric chloride dosages are (15, 40 and 60 ppm) and polyaluminum chloride dosages were (10, 35 and 55 ppm) for initial water turbidity (100, 500 an

... Show More
View Publication Preview PDF