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A three-stage blumlein-circuit to generate transversely excited atmospheric nitrogen laser by using three spark gaps
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In this research constructed N2 laser system by use developed method of electric discharge. In this method used four step of electric discharge by using four capacitors, three spark gaps, high tension power supply varying in range from 12kV to 24 kV and three resistors, this method called three stage blumlein circuit. The breakdown time delay of these parallel spark gaps cement strong ultraviolet preionization in the laser channel, thus the result of these amendments the laser output is many doubled and is more increasing than that obtained using the one and two stage blumlein circuits. This system has been designed and operated to give pulse laser with wavelength at 337.1 nm. This laser system can operate without mirrors and optical resonator. The best result of energy was about (20.2 mJ) at electrode separation (3.5 mm) with flow rate (13 L/min) and applied voltage (24 kV). With this conditions of electric discharges the pulse duration was (6.65 ns) then the peak power was (3.04 MW), the efficiency of convert the electric energy to optical energy was (0. 93%) and The divergence of laser beam at optimal condition was (0.348 mrad). The results of fabricated system indicate the output characteristics can be significantly improved by improving the discharge characteristics.

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Publication Date
Tue Sep 08 2020
Journal Name
Baghdad Science Journal
Radiological Impact Assessment of Farm Soils and Ofada rice (Oryza sativa japonica) from Three Areas in Nigeria
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Oryza sativa japonica (ofada rice) is largely grown in Aramoko, Abakaliki and Ofada are communities and consumed by both the poor and rich in Nigeria. A total of twenty ofada rice farmlands were identified in each study area and rice samples were randomly collected, thoroughly mixed to make a representative sample from each farmland. Soil samples were collected in each farm to a depth of 5-15cm from at least eight different points and thoroughly mixed together to form a representative sample. The samples were thereafter taken to the laboratory for preparation and spectroscopic analysis. A well-calibrated NaI(Tl) gamma-ray detector was used in spectrometric analysis of the samples and descriptive statistics was used to analyze th

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Publication Date
Tue Feb 18 2020
Journal Name
Modelling And Simulation In Engineering
Temperature and Stress Evaluation during Three Different Phases of Friction Stir Welding of AA 7075-T651 Alloy
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The current study performs an explicit nonlinear finite element simulation to predict temperature distribution and consequent stresses during the friction stir welding (FSW) of AA 7075-T651 alloy. The ABAQUS® finite element software was used to model and analyze the process steps that involve plunging, dwelling, and traverse stages. Techniques such as Arbitrary Lagrangian–Eulerian (ALE) formulation, adaptive meshing, and computational feature of mass scaling were utilized to simulate sequence events during the friction stir welding process. The contact between the welding tool and workpiece was modelled through applying Coulomb’s friction model with a nonlinear friction coefficient value. Also, the model considered the effect of nonlin

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Publication Date
Sun Jun 30 2024
Journal Name
Iraqi Journal Of Science
Telescope Mirror Cleaning Using Atmospheric Pressure Multi-Channel Radio Frequency Plasma Jet
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     In this work, the surface of the telescope’s mirror is cleaned using an atmospheric-pressure radio frequency plasma jet (APRFPJ), which is generated by Argon gas between two coaxial metal electrodes. The RF power supply is set to 2 MHz frequencies with three different power levels: 20, 50, and 80 W. Carbon, that has adhered to the surface, can be effectively removed using the plasma cleaning technique, which also modifies any residual bonds. The cleaned surface was clearly distinguished using an optical emission spectroscopy (OES) technique and a water contact angle (WCA) analyzer for the activation property on their surfaces. The sample showed a super hydrophilic surface at an angle of 1° after 2.5 minutes of plasma tre

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Publication Date
Mon Apr 03 2023
Journal Name
The Journal Of Physical Chemistry A
Excited-State Aromaticity Reversals in Naphthalene and Anthracene
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Aromaticity reversals between the electronic ground (S0) and low-lying singlet (S1, S2) and triplet (T1, T2, T3) states of naphthalene and anthracene are investigated by calculating the respective off-nucleus isotropic magnetic shielding distributions using complete-active-space self-consistent field (CASSCF) wavefunctions involving gauge-including atomic orbitals (GIAOs). The shielding distributions around the aromatic S0, antiaromatic S1 (1Lb), and aromatic S2 (1La) states in naphthalene are found to resemble the outcomes of fusing together the respective S0, S1, and S2 shielding distributions of two benzene rings. In anthracene, 1La is lower in energy than 1Lb, and as a result, the S1 state becomes aromatic, and the S2 state becomes anti

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Publication Date
Thu Jan 01 2015
Journal Name
The 2d International Conference Of Buildings, Construction And Environmental Engineering (bcee2-2015)
Terrestrial Laser Scanning to Preserve Cultural Heritage in Iraq Using Monitoring Techniques
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Publication Date
Mon Sep 19 2022
Journal Name
Gynecology And Obstetrics Case Report
A Case Report of Intrauterine Fetal Death with Three Loops of Umbilical Cord around Neck, Keratin Hair Treatment during Pregnancy Could be the Cause
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Publication Date
Tue May 01 2012
Journal Name
Iraqi Journal Of Physics
Controlling the wavelength of a high power diode laser using thermoelectric cooler
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The present work includes a design and characteristics study of a controlling the wavelength of high power diode laser by thermoelectric cooler [TEC] . The work includes the operation of the [TEC] to control the temperature of the diode laser between ( 0- +30) °C by changing the resistance of thermistor. We can control a limited temperature of a diode laser by changing the phase cooling between hot and cold faces of the diode, this process can be attempted by comparator type [LM –311] .The theoretical results give a model for controlling the temperature with, the suitable wavelength.

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Publication Date
Wed Dec 27 2017
Journal Name
Al-khwarizmi Engineering Journal
A New Structure for Cascaded Single-Stage Distributed Amplifier Using Proposed Active Inductor Loads
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A modification to cascaded single-stage distributed amplifier (CSSDA) design by using active inductor is proposed. This modification is shown to render the amplifier suitable for high gain operation in small on-chip area. Microwave office program simulation of the Novel design approach shows that it has performance compatible with the conventional distributed amplifiers but with smaller area. The CSSDA is suitable for optical and satellite communication systems.

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Publication Date
Wed Jun 11 2003
Journal Name
Iraqi Journal Of Laser
Microdrop Size Measurement in a Mixing Unit Using Laser Technique
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One of the troublesome duties in chemical industrial units is determining the instantaneous drop size distribution, which is created between two immiscible liquids within such units. In this work a complete system for measuring instantaneous droplet size is constructed. It consists of laser detection system (1mW He-Ne laser), drop generation system (turbine mixer unit), and microphotography system. Two immiscible liquids, water and kerosene were mixed together with different low volume fractions (0.0025, 0.02) of kerosene (as a dispersed phase) in water (as a continuous phase). The experiments were carried out at different rotational speed (1180- 2090 r.p.m) of the turbine mixer. The Sauter mean diameter of the drops was determined by la

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Publication Date
Sun Feb 03 2019
Journal Name
Iraqi Journal Of Physics
Electrical properties of pure NiO and NiO:Au thin films prepared by using pulsed laser deposition
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The electrical properties of pure NiO and NiO:Au Films which are
deposited on glass substrate with various dopant concentrations
(1wt.%, 2wt%, 3wt.% and 4wt.%) at room temperature 450 Co
annealing temperature will be presented. The results of the hall effect
showed that all the films were p-type. The Hall mobility decreases
while both carrier concentration and conductivity increases with the
increasing of annealing temperatures and doping percentage, Thus,
indicating the behavior of semiconductor, and also the D.C
conductivity from which the activation energy decrease with the
doping concentration increase and transport mechanism of the charge
carriers can be estimated.

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