Preferred Language
Articles
/
joe-2196
Modeling of Electron and Lattice Temperature Distribution Through Lifetime of Plasma Plume
...Show More Authors

When employing shorter (sub picosecond) laser pulses, in ablation kinetics the features appear which can no longer be described in the context of the conventional thermal model. Meanwhile, the ablation of materials with the aid of ultra-short (sub picosecond) laser pulses is applied for micromechanical processing. Physical mechanisms and theoretical models of laser ablation are discussed. Typical associated phenomena are qualitatively regarded and methods for studying them quantitatively are considered. Calculated results relevant to ablation kinetics for a number of substances are presented and compared with experimental data. Ultra-short laser ablation with two-temperature model was quantitatively investigated. A two-temperature model for the description of transition phenomena in a non-equilibrium electron gas and a lattice under picosecond laser irradiation is proposed. Some characteristics are hard to measure directly at all. That is why the analysis of physical mechanisms involved in the ablation process by ultra-short laser pulses has to be performed on the basis of a theoretical consideration of `indirect' experimental data. For Copper and Nickel metal targets, the two-temperature model calculations explain that the temperature of the electron subsystem increased suddenly and approached a peak value at the end of laser pulse. In addition, the temperature profile of lattice temperature subsystem evolution slowly, and still increasing after the end of laser pulse. A good agreement prevails when a comparison between the present results and published results.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Sep 30 2015
Journal Name
College Of Islamic Sciences
Jurisprudence of Imam women through Susan Book of blood money
...Show More Authors

Jurisprudence of Imam women through Susan Book of blood money

View Publication Preview PDF
Publication Date
Tue Dec 26 2017
Journal Name
Al-khwarizmi Engineering Journal
Experimental Modeling and Optimization of Fatigue Life and Hardness of Carbon Steel CK35 under Dynamic Buckling
...Show More Authors

Abstract

 

The aim of this paper is to model and optimize the fatigue life and hardness of medium carbon steel CK35 subjected to dynamic buckling. Different ranges of shot peening time (STP) and critical points of slenderness ratio which is between the long and intermediate columns, as input factors, were used to obtain their influences on the fatigue life and hardness, as main responses. Experimental measurements of shot peening time and buckling were taken and analyzed using (DESIGN EXPERT 8) experimental design software which was used for modeling and optimization purposes. Mathematical models of responses were obtained and analyzed by ANOVA variance to verify the adequacy of the models. The resul

... Show More
View Publication Preview PDF
Publication Date
Fri Oct 01 2010
Journal Name
Iraqi Journal Of Physics
The axial profile of plasma characteristics of cylindrical magnetron sputtering device
...Show More Authors

In the present work, a d.c. magnetron sputtering system was designed and fabricated. The chamber of this system was includes from two copper coaxial cylinders where the inner one used as a cathode (target) while the outer one used as the anode with Solenoid magnetic coil located on the outer cylinder (anode). The axial profile of magnetic field for various coil current (from 2A to 14 A) are shown. The plasma characteristics in the normal glow discharge region are diagnostics by the 2.2mm diameter Langmuir probe with different length along the cathode and located at different radial positions 1cm and 2cm from the cathode surface. The result of this work shows that, the electron energy distributions at different radial positions along the

... Show More
View Publication Preview PDF
Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Influence of grounded electrode area on breakdown current in RF capcitively coupled plasma
...Show More Authors

The influence of the grounded electrode area on the ignition voltage in capcitively coupled radio frequency discharge at 13.56 MHz in argon gas is studied experimentally. The results indicate a systematic decrease of the breakdown voltage with increasing grounded electrode area for the same pd value. Results show that the secondary ionization coefficient γ increases with the increase of grounded electrode area. Furthermore, results also the discharge current at the breakdown voltage increases almost linearly with the increase of electrode area suggesting an almost constant current density.

View Publication Preview PDF
Publication Date
Sat Feb 15 2025
Journal Name
Iraqi Journal Of Science
Effect of Aluminum Dust Particles on Plasma Parameters at Different Gas Pressure with Different Dust Contents
...Show More Authors

In this work, the effect of aluminum (Al) dust particles on the DC discharge plasma properties in argon was investigated. A magnetron is placed behind the cathode at different pressures and with varying amounts of Al. The plasma temperature (Te) and density (ne) were calculated using the Boltzmann equation and Stark broadening phenomena, which are considered the most important plasma variables through which the other plasma parameters were calculated. The measurements showed that the emission intensity decreases with increasing pressure from 0.06 to 0.4 Torr, and it slightly decreases with the addition of the NPs. The calculations showed that the ne increased and Te decreased with pressure. Both Te and ne were reduced by increasing

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
On Shrunken Estimation of Generalized Exponential Distribution
...Show More Authors

This paper deal with the estimation of the shape parameter (a) of Generalized Exponential (GE) distribution when the scale parameter (l) is known via preliminary test single stage shrinkage estimator (SSSE) when a prior knowledge (a0) a vailable about the shape parameter as initial value due past experiences as well as suitable region (R) for testing this prior knowledge.

The Expression for the Bias, Mean squared error [MSE] and Relative Efficiency [R.Eff(×)] for the proposed estimator are derived. Numerical results about beha

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Planning of Distribution Networks in Baghdad City
...Show More Authors

Planning of electrical distribution networks is considered of highest priority at the present time in Iraq, due to the huge increase in electrical demand and expansions imposed on distribution networks as a result of the great and rapid urban development.

Distribution system planning simulates and studies the behavior of electrical distribution networks under different operating conditions. The study provide understanding of the existing system and to prepare a short term development plan or a long term plan used to guide system expansion and future investments needed for improved network performance.

The objective of this research is the planning of Al_Bayaa 11 kV distribution network in Baghdad city bas

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 01 2023
Journal Name
Palestine Journal Of Mathematics
STATISTICAL PROPERTIES OF GENERALIZED EXPONENTIAL RAYLEIGH DISTRIBUTION
...Show More Authors

This paper demonstrates the construction of a modern generalized Exponential Rayleigh distribution by merging two distributions with a single parameter. The "New generalized Exponential-Rayleigh distribution" specifies joining the Reliability function of exponential pdf with the Reliability function of Rayleigh pdf, and then adding a shape parameter for this distribution. Finally, the mathematical and statistical characteristics of such a distribution are accomplished

View Publication Preview PDF
Scopus (4)
Scopus
Publication Date
Fri Jan 01 2021
Journal Name
International Journal Of Agricultural And Statistical Sciences
MODELING DEATH RATE OF THE COVID-19 PANDEMIC IN IRAQ
...Show More Authors

View Publication Preview PDF
Scopus
Publication Date
Tue Dec 15 2020
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees20
Studying properties of propagated transverse modes through optical fibers
...Show More Authors

View Publication
Scopus (5)
Crossref (3)
Scopus Clarivate Crossref