Preferred Language
Articles
/
ijs-5576
Influence of Cylindrical Electrode Configuration on Plasma Parameters in a Sputtering System

      In the present work, the effect of the cylindrical configurations of the sputtering device electrodes on the plasma parameters (Debye length, electron temperature, electron density, plasma frequency) is studied. Also, the effect of the argon gas pressure on the discharge properties is examined with gas pressures of (0.08, 0.2, 0.4 and 0.6) Torr. The properties of the plasma are diagnosed by optical emission spectrometry. The spectroscopic method is adopted for examining the atomic spectra of argon emission.  The electron temperature is determined by the Boltzmann method. While, the Stark-widening method was employed for calculating the electron number density. The voltage against current curves of the cylindrical sprayer discharges shows the voltage to be nearly constant with slight increase in current. An increase in pressure causes the cathode cascades to compress and the negative glow to become thinner and more luminous. Plasma properties such as electron temperature and Debye length  decrease with increasing pressure, while electron number density and plasma frequency increase.

Scopus Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Sep 30 2023
Journal Name
Iraqi Journal Of Science
Townsend Discharge and Streamer Breakdown within Sphere-Air-Sphere Configuration

     The main aim of the present paper is to study the electric breakdown in a uniform electric discharge system. The system consists of two spheres separated by a dielectric. The dielectric is dry air. Certain boundary conditions are taken into consideration as applied voltage, pressure, and domain. The formation of discharge types as Townsend and streamer under different distance gaps (1, 0.9,0.8, 0.6, 0.4, 0.2, 0.1) mm was sudied. The temperature effect on the breakdown voltages for the discharge process is also included. Seven different temperature steps are chosen in the study.  Comsol Multiphysics software is used for the simulation model as a plasma model. Results show that as the gap distance increases the breakdown voltage

... Show More
Scopus Crossref
View Publication Preview PDF
Publication Date
Fri Mar 15 2019
Journal Name
Al-khwarizmi Engineering Journal
Theoretical Prediction of Optimum Chilled Water Distribution Configuration in Air Conditioning Terminal Unit

 The distribution of chilled water flow rate in terminal unit is a major factor used to evaluate the performance of central air conditioning unit. In this work, a theoretical chilled water distribution in the terminal units has been studied to predict the optimum heat performance of terminal unit. The central Air-conditioning unit model consists of cooling/ heating coil (three units), chilled water source (chiller), three-way and two-way valve with bypass, piping network, and pump. The term of optimization in terminal unit ingredient has two categories, the first is the uniform of the water flow rate representing in statically permanents standard deviation (minimum value) and the second category is the maximum heat transfer rate fro

... Show More
Crossref
View Publication Preview PDF
Publication Date
Wed Oct 28 2020
Journal Name
Iraqi Journal Of Science
Optical and Structural Properties of Titanium Dioxide Papered by DC Magneto-Sputtering as a NO2 Gas Sensor

 In this work, a reactive DC magnetron sputtering technique was used to prepare TiO2 thin films. The variation in argon and oxygen gases mixing ratios (4:1, 2:1, 1:1, 1:2, 1:4) was used to achieve optimal properties for gas sensing. In addition, an analysis of the optical XRD properties of TiO2 thin films is presented. High-quality and uniform nanocrystalline films were obtained at a working gas pressure of 0.25 mbar and  1:4 (Ar/O2) gas mixture. The optical properties showed a transparent thin film with uniform adherence to the substrate. The average transmission of the TiO2 films deposited on the glass substrates was higher than 95% over the range of 400 to 800 nm.

... Show More
Scopus (8)
Crossref (5)
Scopus Crossref
View Publication Preview PDF
Publication Date
Fri Jan 01 2021
Journal Name
Agrosystems, Geosciences & Environment
Cover crop influence on soil water dynamics for a corn–soybean rotation
Abstract<p>Crop production is reduced by insufficient and/or excess soil water, which can significantly decrease plant growth and development. Therefore, conservation management practices such as cover crops (CCs) are used to optimize soil water dynamics, since CCs can conserve soil water. The objective of this study was to determine the effects of CCs on soil water dynamics on a corn (<italic>Zea mays</italic> L.)–soybean [<italic>Glycine max</italic> (L.) Merr.] rotation at three soil depths over 3 yr. The study was conducted at the Chariton County Cover Crop Soil Health Research and Demonstration Farm (CCSH) in Missouri. Initial CC establishment occurred in 2012. Volumetric soil water </p> ... Show More
Scopus (12)
Crossref (9)
Scopus Clarivate Crossref
View Publication
Publication Date
Sun Jul 31 2022
Journal Name
Iraqi Journal Of Science
Scopus (2)
Crossref (1)
Scopus Crossref
View Publication Preview PDF
Publication Date
Wed Aug 01 2018
Journal Name
International Journal Of Novel Research In Electrical And Mechanical Engineering
Use of Panel Method in High Subsonic and Transonic Aerodynamic Analysis of Complex Aircraft Configuration

The application of low order panel method with the Dirichlet boundary condition on complex aircraft configuration have been studied in high subsonic and transonic speeds. Low order panel method has been used to solve the case of the steady, inviscid and compressible flow on a forward swept wing – canard configuration with cylindrical fuselage and a vertical stabilizer with symmetrical cross section. The aerodynamic coefficients for the forward swept wing aircraft were calculated using measured wake shape from an experimental work on same model configuration. The study showed that the application of low order panel method can be used with acceptable results

View Publication
Publication Date
Tue Mar 01 2016
Journal Name
Al-academy
Configuration semantics in Tmthbla freedom and Eid Ghadir: حسام عبد الخالق عثمان

The research is a special case of semantics modern Iraqi art, especially with regard to the art of sculpture, and the exact Nasba sculpture, has included research, four chapters on whale1. The first chapter: which consisted of:A. The research problem.B. The importance of research.C. Find goal.H. Find borders.Kh. Determine the terms.2. Chapter II: The theoretical framework: which consisted ofA. The first topic: sculptured configuration.B. The second topic:1. The first axis: contemporary Iraqi sculpture.2. The second axis: the sculptor Jawad Salim.3. The third axis: Mohammed sculptor debateC. Theoretical framework indicators.D. Previous studies.3. Chapter III: proceedings: which included:A. Find community.B. The research sample.C. Research

... Show More
Crossref
View Publication Preview PDF
Publication Date
Sat Oct 01 2022
Journal Name
The Egyptian Journal Of Hospital Medicine
Scopus Crossref
View Publication
Publication Date
Sat Jun 01 2024
Journal Name
Results In Engineering
Scopus (1)
Crossref (1)
Scopus Clarivate Crossref
View Publication
Publication Date
Wed Dec 30 2009
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Mass Transfer Correlations for a Rotating Cylinder Electrode under lsothermal and Controlled Heat Transfer Condition

Mass transfer correlations for iron rotating cylinder electrode in chloride/sulphate solution, under isothermal and
controlled heat transfer conditions, were derived. Limiting current density values for the oxygen reduction reaction from
potentiostatic experiments at different bulk temperatures and various turbulent flow rates, under isothermal and heat
transfer conditions, were used for such derivation. The corelations were analogous to that obtained by Eisenberg et all
and other workers.

View Publication Preview PDF