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Modeling of Plasma Affected Thermal Profile in Solids During Laser Materials Processing
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A new scheme of plasma-mediated thermal coupling has been implemented which yields the temporal distributions of the thermal flux which reaches the metal surface, from which the spatial and temporal temperature profiles can be calculated. The model has shown that the temperature of evaporating surface is determined by the balance between the absorbed power and the rate of energy loss due to evaporation. When the laser power intensity range is 107 to108 W/cm2 the temperature of vapor could increase beyond the critical temperature of plasma ignition, i.e. plasma will be ignited above the metal surface. The plasma density has been analyzed at different values of vapor temperature and pressure using Boltzmann’s code for calculation of electron distribution function. This analysis has been used to determine the temporal distribution of the net heat flux, which reaches the solid surface. The net heat flux has been proved to vanish at high plasma density. Accordingly the temporal and spatial distributions of temperature profiles within the solid metal have been modeled depending upon the net heat flux which reaches the target surface.

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Publication Date
Tue Jun 14 2005
Journal Name
Iraqi Journal Of Laser
Design and Operation of Mini-TEA CO2 Laser and Investigation of Preionization Effect
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A Mini-TEA CO2 laser system was designed and operated to obtain a pulse at 10.6 μm. Output energy of 30 mJ, with preionization pins, and pulse duration of 100ns were obtained. While an output energy of 6mJ and pulse duration of 100 ns in absence of pre-ionization were obtained. The system was operated with Ernest profile main-discharge electrodes. Dependencies of supply voltage and output laser energy on the pressure inside laser cavity were investigated as well as dependencies of supply voltage and output energy on the main capacitor(8CO2 : 8N2 : 82He :2CO). Efficiency of was calculated to be 4.4%.

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Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Writing of a Bragg Grating on a D-shaped Optical Fiber Using the KrF Excimer Laser
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Fiber Bragg Grating has many advantages where it can be used as a temperature sensor, pressure sensor or even as a refractive index sensor. Designing each of this fiber Bragg grating sensors should include some requirements. Fiber Bragg grating refractive index sensor is a very important application. In order to increase the sensing ability of fiber Bragg gratings, many methods were followed. In our proposed work, the fiber Bragg grating was written in a D-shaped optical fiber by using a phase mask method with KrFexcimer. The resultant fiber Bragg grating has a high reflectivity 99.99% with a Bragg wavelength of 1551.2 nm as a best result obtained from a phase mask with a grating period of 1057 nm. In this work it was found that the rota

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Publication Date
Tue Jun 30 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Raised excessive consumption on environment and price levels during the period 2005- 2013.: Raised excessive consumption on environment and price levels during the period 2005- 2013.
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When the financial resources of individuals and groups available, this will lead to increase the consumption ranges and sometimes reached to excessive especially to the categories that have little awareness about economic importance and its reflections. it seems that consumerism has increased in many countries including Iraq because of many factors, and the most important one is the availability of financial resources as a result of the increase in oil exports as well as the spread of consumption media department at various levels especially.

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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
Thermal Modeling of Solar Still Coupled with Heat Pipes and Experimental Validation
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Water is the basis of the existence of all kinds of life, so obtaining it with good quality represents a challenge to human existence and development especially in the desert and remote cities because these areas contain small populations and water purification requires great materials and huge amounts of fossil fuels resulting pollution of the environment. Cheap and environmentally friendly desalination methods have been done by using solar distillations. Passive solar stills have low yields, so in this research, the problem is overcome by connecting four heat pipes which are installed on the parabolic concentrator reflector with passive solar still to increase the temperature of hot water to more than 90°C, as a resul

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Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Numerical Investigation of Transient Heat Conduction through a Thermal Insulation of Temperature Dependant Thermal Properties
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The two-dimensional transient heat conduction through a thermal insulation of temperature dependent thermal properties is investigated numerically using the FVM. It is assumed that this insulating material is initially at a uniform temperature. Then, it is suddenly subjected at its inner surface with a step change in temperature and subjected at its outer surface with a natural convection boundary condition associated with a periodic change in ambient temperature and heat flux of solar radiation. Two thermal insulation materials were selected. The fully implicit time scheme is selected to represent the time discretization. The arithmetic mean thermal conductivity is chosen to be the value of the approximated thermal conductivity at the i

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Publication Date
Wed Jun 01 2022
Journal Name
Iranian Journal Of Chemistry And Chemical Engineering
The Thermal Pre-processing Technique of the Bio-waste for Contaminated Water Treatment: Histological and Experimental Study
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The current study suggested a thermal treatment as a necessary proactive step in improving the adsorption capacity of bio-waste for contaminants removal in wastewater. This approach was based on the experimental and histological investigation of biowaste pods shell. This investigation showed that these shells compose of parenchyma cells that store secondary metabolites compounds produced from cells were exhibited in present study. The results also reported that these compounds are extracted directly from the cells as soon as they are exposed to an aqueous solution, hampering their use as an adsorbent material. The increase in the weight of bio-waste adsorbent at unit liquid volume increases the production of secondary metabolites compounds

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Publication Date
Thu Nov 29 2018
Journal Name
Journal Of Electronic Materials
Numerical Modeling of 193-nm Excimer Laser Ablation on CR-39 Polymer
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Publication Date
Wed Jun 07 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effectiveness of a Program in Developing Awareness of the Criteria for Judging Electronic Educational Materials Among Students of Teaching Diploma at Dhofar University
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The study aims to develop the awareness of the criteria for judging electronic educational materials among students of educational qualification at Dhofar University over spreading the Corona pandemic through a program based on mini-educational units. The study was applied to (18) students studying Teaching diploma at Dhofar University for the academic year 2020-2021, and their number. They were chosen intentionally. The study resulted in reaching a list of criteria for judging electronic educational materials, roughly (18) criteria in the selection themes and (15) criteria in the use theme. The level of awareness of the sample members with the criteria for selecting and using electronic educational materials and the effectiveness of the

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Publication Date
Thu Jan 10 2019
Journal Name
Journal Of The College Of Education For Women
Solid waste raised in the city of Baghdad Environment
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Most cities in the world are suffering from the problem of solid waste and the resting adverse impact on the environment and public health, in particular the spread of diseases, insects and rodents, As well as the proliferation of nuisance odors result of provided by the responsible parties, As wall as weak environmental awareness among those who dwell in dealing in environmentally sound disposal of solid waste, this study was  bembgesan  first intake of solid waste and the kinds of concept and components by land use, As wall as the effects of solid waste on the environment spatial, factors affecting the quality and quantity of solid waste, the second topic was included as a study field presented the historical city of Baghdad

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Publication Date
Sat Oct 01 2022
Journal Name
International Journal Of Nanoscience
Preparation and Physical Properties of Mg-Zn Nano-crystal by Laser-induced Plasma
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To learn how the manner of preparation influences film development, this study examined film expansion under a variety of deposition settings. To learn about the membrane’s properties and to ascertain the optimal pretreatment conditions, which are represented by ambient temperature and pressure, Laser pressure of 2.5[Formula: see text]m bar, the laser energy density of 500[Formula: see text]mJ, distortion ratio ([Formula: see text]) as a function of laser pulse count, all achieved with the double-frequency Nd: YAG laser operating in quality-factor mode at 1064[Formula: see text]nm. MgxZn[Formula: see text] films of thickness [Formula: see text][Formula: see text]nm were deposited on glass substrates at pulse

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