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jih-3353
Theoretical Study of the Lasing Output for a Quasi-Three-Level Operation in Nd 3+:YAG Thin- Disk Laser

In this research, the effect of each of the concentrations ( Nd+3) was studied (N) the thickness of the thin disk (d) the number of times that the pumping beam passes through the effective medium of this laser (Mp) the reflectivity of the laser output mirror (R 2) The losses of the effective medium (L) and the pumping power used in achieving the reverse qualification (PP) on each of the pumping threshold capacities (Pp.th) and the output power of the laser (Pout) and the efficiency (ŋ) in Nd3+ thin-disk lasers (TDLs) pumping quasi-three-level With continuous operation (cw), at room temperature, and in the Gaussian mode (TEM00),

We found under these operating conditions for this laser design that each of the (Pout) and (ŋ) increases by increasing each of (N), (d), (MP), and (R2), while the ( pp.th) decreases with this increase. We also found that as the losses (L) increases (pout) and (ŋ) decrease, and (pp.th) increase, as for increasing the pumping capacity, it leads to an increase in (Pout) only. Both (Pout) and (ŋ) are not affected by such an increase. In light of these results, the typical values for these coefficients were determined, and then you get the highest value for pout and (ŋ) the lowest value for (pp.th) for this laser design under the operating conditions that were adopted in this research.

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Publication Date
Wed Jul 28 2021
Journal Name
Journal Of Legal Sciences
The Quasi-Contract in the English Law. A Comparative Study with the Unjustly Paid in the Iraqi Civil Law

Quasi-contract is considered as one of the well-established legal systems of the English Common law of customary origins, which is unwritten and based upon judicial precedents of the English courts. It is worth-bearing in mind that the legal basis of quasi-contract passed into two different stages: in the first stage the English judicature, supported by some juristic opinions regarded it as an implied Contract made by courts to prevent one party from being unjustly enriched at the expense of the other. Whereas in the second stage the English judicature considered it as an independent source of obligation، based upon the law of restitution. and having nothing to do with the law of contract. The Iraqi civil law No. (40) of 1951 regulated

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Publication Date
Thu Jun 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
CFD Simulation of Air Flow Patterns in a Spray Dryer Fitted With a Rotary Disk

The air flow pattern in a co-current pilot plant spray dryer fitted with a rotary disk atomizer was determined experimentally and modelled numerically using Computational Fluid Dynamics (CFD) (ANSYS Fluent ) software. The CFD simulation used a three dimensions system, Reynolds-Average Navier-Stokes equations (RANS), closed via the RNG k −ε turbulence model. Measurements were carried out at a rotation of the atomizer (3000 rpm) and when there is no rotation using a drying air at 25 oC and  air velocity at the inlet of  5 m/s without swirl. The air flow pattern was predicted experimentally using cotton tufts and digital anemometer. The CFD simulation predicted a downward central flowing air core surrounded by a slow

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Publication Date
Wed Mar 01 2023
Journal Name
Iraqi Journal Of Physics
Theoretical Computation of Electron Density in Laser-Induced Carbon Plasma using Anisimov Model

In this work, electron number density calculated using Matlab program code with the writing algorithm of the program. Electron density was calculated using Anisimov model in a vacuum environment. The effect of spatial coordinates on the electron density was investigated in this study. It was found that the Z axis distance direction affects the electron number density (ne). There are many processes such as excitation; ionization and recombination within the plasma that possible affect the density of electrons. The results show that as Z axis distance increases electron number density decreases because of the recombination of electrons and ions at large distances from the target and the loss of thermal energy of the electrons in

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Publication Date
Fri Jul 18 2014
Journal Name
International Journal Of Computer Applications
3-Level Techniques Comparison based Image Recognition

Image recognition is one of the most important applications of information processing, in this paper; a comparison between 3-level techniques based image recognition has been achieved, using discrete wavelet (DWT) and stationary wavelet transforms (SWT), stationary-stationary-stationary (sss), stationary-stationary-wavelet (ssw), stationary-wavelet-stationary (sws), stationary-wavelet-wavelet (sww), wavelet-stationary- stationary (wss), wavelet-stationary-wavelet (wsw), wavelet-wavelet-stationary (wws) and wavelet-wavelet-wavelet (www). A comparison between these techniques has been implemented. according to the peak signal to noise ratio (PSNR), root mean square error (RMSE), compression ratio (CR) and the coding noise e (n) of each third

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Publication Date
Wed Jun 30 2004
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
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Publication Date
Mon May 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Preparing the Thin Films from Laser Dye Dopped with Polymer and Measuring Thickness

 Thin films were prepared from melting coumrin C 2 dye in solvent DMF with PMMA with the same  solvent and concentrations(1*10-2    5*10-3, 1*10-3  )M ,Films were either left on Flat surface for24hours or dried in avacuum oven for five hours at a temperature of 80c.The relative intensity of both the absorption and fluorescece spectrum are found to be increased with the increase of thickness of these films and concentration  .Also the thickness of these films was measured by Mickelsons interfearing method.Also quantum efficiency of these films were measured too

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Publication Date
Thu Jun 01 2023
Journal Name
Journal Of Engineering
A Control Program for Hydropower Operation Based on Minimizing the Principal Stress Values on the Dam Body: Mosul Dam Case Study

This study examines the vibrations produced by hydropower operations to improve embankment dam safety. This study consists of two parts: In the first part, ANSYS-CFX was used to generate a three-dimensional (3-D) finite volume (FV) model to simulate a vertical Francis turbine unit in the Mosul hydropower plant. The pressure pattern result of the turbine model was transformed into the dam body to show how the turbine unit's operation affects the dam's stability. The upstream reservoir conditions, various flow rates, and fully open inlet gates were considered. In the second part of this study, a 3-D FE Mosul dam model was simulated using an ANSYS program. The operational turbine model's water pressure pattern is conveyed t

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Publication Date
Thu Oct 14 2021
Journal Name
Iraqi Journal Of Physics
Investigation of nonlinear optical properties for laser dyes-doped polymer thin film

Solutions of dyes Rhodamine 6G (Rh6G) and Coumarin480(C480) were prepared at five concentrations (1x10-3, 5x10-4, 1x10-4, 5x10-5 and1x10-5) mol/l, the mixing was stirred to obtain on a homogenous solution, the(poly methyl-methacrylate) (PMMA) was solved by chloroform solvent with certain ratio, afterward (PMMA+Rh6G) and (PMMA+C480) thin films were prepared by casting method on glass block which has substrate with dimensions (7.5 x2.5)cm2, the prepared samples were left in dark place at room temperature for 24 hours to obtain uniform and homogenous thin films. UV-VIS absorption spectra, transmission spectra and fluorescence spectra were done to measure linear refractive index and linear absorption coefficient. The nonlinear optical proper

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Publication Date
Tue Sep 18 2018
Journal Name
Water
A Systematic Operation Program of a Hydropower Plant Based on Minimizing the Principal Stress: Haditha Dam Case Study

Dam operation and management have become more complex recently because of the need for considering hydraulic structure sustainability and environmental protect on. An Earthfill dam that includes a powerhouse system is considered as a significant multipurpose hydraulic structure. Understanding the effects of running hydropower plant turbines on the dam body is one of the major safety concerns for earthfill dams. In this research, dynamic analysis of earthfill dam, integrated with a hydropower plant system containing six vertical Kaplan turbines (i.e., Haditha dam), is investigated. In the first stage of the study, ANSYS-CFX was used to represent one vertical Kaplan turbine unit by designing a three-dimensional (3-D) finite element (F

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Publication Date
Wed Mar 18 2020
Journal Name
Baghdad Science Journal
Effect of CO2 Laser Irradiation on the Topographic and Optical Properties of CdO Thin Films

     In this study, cadmium oxide (CdO) was deposited on glass bases by thermal chemical spraying technique at three concentrations (0.05, 0.1, 0.15) M and then was irradiated by CO2 laser with 10.6 μm wave length and 1W power. The results of the atomic force microscope AFM test showed that the surfaces of these CdO thin films were homogenous and that the laser irradiated effect resulted in decreasing the roughness of the surface as well as the heights of the granular peaks, indicating a greater uniformity and homogeneity of the surfaces. The optical properties were studied to determine laser effect. The results of optical tests of these thin films showed that the photoluminescence spectra and absorption s

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