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ijp-965
The Confinement Profile Effect on the Optical Properties in Different Inverse-shaped Single InGaN/GaN Quantum Wells
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In this work, the effects of size, and temperature on the linear and nonlinear optical properties in InGaN/GaN inverse parabolic and triangular quantum wells (IPQW and ITQW) for different concentrations at the well center were theoretically investigated. The indium concentrations at the barriers were fixed to be always xmax = 0.2. The energy levels and their associated wave functions are computed within the effective mass approximation. The expressions of optical properties are obtained analytically by using the compact density-matrix approach. The linear, nonlinear, and total absorption coefficients depending on the In concentrations at the well center are investigated as a function of the incident photon energy for different values of temperature and quantum wells size. The results show that the In concentrations, size and temperature have a significant effect on these optical properties. The positions of the resonance peaks of the absorption coefficients were blue-shifted under increasing indium compositions in the quantum wells (InGaN) and temperature while they were red-shifted with the increase in the thickness of the wells. Moreover, the amplitudes of the resonance peaks were enhanced under the increase of the In composition, the temperature, and the thickness of the quantum wells. The optical absorption in ITQW structure is slightly greater than that in IPQW one.

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Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Studying of the optical properties of poly (vinyl alcohol) films using Aluminum sulphate as additive by measuring allowed direct transition energy gap
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The change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.

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Publication Date
Sun Dec 15 2019
Journal Name
Al-academy
The Effect of The Illustration Program on Fashion Design Inspired by Historical Costumes: تهاني ناصر العجاجي -هدى عبد العزيز المقرن
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This research aims to identify the role and impact of illustrations in contemporary fashion design inspired by historical costumes. Historical fashion aesthetics are adapted to design drawings. The experimental method was followed and a sample of 31 students in the department of fashion and textile design, third level were selected. Each student carried out two original historical and contemporary design. The models were executed two times: one with the usage of the program and the other without program help. The tools that were used are the program, the scale, the pre-skill test, and the post-skill test. One of the most relevant results of the research is the possibility of using historical costumes to highlight creativity and innovatio

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Publication Date
Fri Mar 31 2017
Journal Name
Al-khwarizmi Engineering Journal
Mechanical Properties Investigation of Composite Material Under Different Parameters Variations
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         The main objective of this research is to design and select a composite plate to be used in fabricating wing skins of light unman air vehicle (UAV). The mechanical properties, weight and cost are the basis criteria of this selection. The fiber volume fraction, fillers and type of fiber with three levels for each were considered to optimize the composite plate selection. Finite element method was used to investigate the stress distribution on the wing at cruise flight condition in addition to estimate the maximum stress. An experiments plan has been designed to get the data on the basis of Taguchi technique. The most effective parameters at the process to be find out by employing L9

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Publication Date
Mon Jan 01 2024
Journal Name
E3s Web Of Conferences
Environmental assessment of the qualitative characteristics of groundwater wells in Ali Al-Gharbi District (north of Maysan Governorate)
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Providing clean water suitable for drinking, agriculture and living organisms is essential in the ecosystem. Therefore, the qualitative assessment of water resources using qualitative indicators is considered one of the most appropriate ways to manage water and develop a regular program for water quality. In this research, 11 sites were used in the Ali Al-Gharbi district in order to evaluate the quality of water in these sites and compare it with international and Iraqi standards and its suitability for drinking. Agriculture, as the results showed that most of the concentrations of the qualitative specifications of the studied characteristics are not suitable for human use and agriculture in the study area.

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Publication Date
Sun Apr 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Effect of Development International Financial Reporting Standards (IFRS) in Quality of Accounting Information for sample of banks listed on the Iraq Stock Exchange
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The bodies responsible for the organization of accounting in the world seek to keep abreast of repaid development, by provide the information required by users, which they need to make efficient decision that return them to the desired benefits, and avoid the risks they could face if they made their decision based on misleading information, or insufficient, or not accurate, Hence, the IASB has undertaken to review the standards, and make the necessary adjustment and clarifications to remove the ambiguities that some of the paragraphs may have in IFRS issued.

And the Iraqi Central Bank obliges banks to convert from local accounting standards to apply IFRS only a step towards keeping pace with developments

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Publication Date
Thu Apr 01 2021
Journal Name
Basra Journal Of Science
Organic Field Effect Transistor Based on P3HT with Two Different Gate Dielectrics
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The electrical performance of bottom-gate/top source-drain contact for p-channel organic field-effect transistors (OFETs) using poly(3-hexylthiophene) (P3HT) as an active semiconductor layer with two different gate dielectric materials, Polyvinylpyrrolidone (PVP) and Hafnium oxide (HfO2), is investigated in this work. The output and transfer characteristics were studied for HfO2, PVP and HfO2/PVP as organic gate insulator layer. Both characteristics show a high drain current at the gate dielectric HfO2/PVP equal to -0.0031A and -0.0015A for output and transfer characteristics respectively, this can be attributed to the increasing of the dielectric capacitance. Transcondactance characteristics also studied for the three organic mater

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Publication Date
Thu Jul 21 2022
Journal Name
Al-academy
تجنيس الأسلوب في الحقل البصري
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لا يوجد نتاج حضاري يخلو من خطاب الأسلوب، كما أنَّ الأسلوب هو أحد المرتكزات المهمة في العملية الفنية وفي الإطار الذي يُحدد علاقة المُنجِز (الفنان) بالعمل الفني، ومن ثَمَّ بالذوق العام. وبرغم أهمية الأسلوب في العمل الفني والأدبي، لم يفرز هذا المصطلح حتى الآن، كما أن مؤسسات الأسلوب وسماته ما زالت غير محددة، ولغياب التعيينات المعرفية لمفهوم (الأسلوب) وبسبب مرونة هذا المصطلح، أصبح من الممكن سحبه باتج
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Publication Date
Tue Aug 30 2016
Journal Name
Mechanical Engineering
The Effect of Different Furrow Depths and Speeds of Machinary Units Using A Locally Assembled Combine Implement on Planting Maize
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Publication Date
Tue Mar 27 2018
Journal Name
Mustansiria Dental Journal
The Effect of Modified Carisolv Gel on Surface Roughness of two Different Types of Ceramic Materials Using Light Polarizing Microscope
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This in vitro study evaluated the influence of chemomechanical caries removal solution on the surface topography of metal-ceramic feldspar porcelain (MAJOR ceramic) and All-ceramic feldspar porcelain (Vita Alpha) using light polarizing microscope. Forty specimens of MAJOR ceramic and forty specimens of Vita Alpha ceramic of (12mm diameter & 3mm height) were prepared .All specimens were polished with silicon polishing burs, cleaned, autoglazed and stored in 37°C before exposure to Carisolv. Thirty specimens of each material randomly exposed to Carisolv gel for 5, 10 and 20 minutes respectively, other ten specimens were not, to act as control group. All specimens were subjected to surface roughness test by profilometer and evalua

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Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Engineering
Dust Effect on the Efficiency of Silicon Mono Crystalline Solar Modules at Different Tilt Angles at Al-Jadryia Climate Conditions
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Solar energy usage in Iraq is facing many issues; one of those is the accumulation “of the dust on the surface of the solar module which” would highly lower its efficiency. The present work study the effect of dust accumulation” on installing fixed solar modules with different inclined angles 15o, 33o, 45o, 60o. Evaluation of the solar modules performance under different circumstance conditions such as rain, wind and humidity are considered in study of dust effect on solar module performance. The results show that the lowest output average efficiencies of solar modules occurs at 15o horizontally inclined angle are 7.4% , 6.7% , 8.0% , 8.1%, and 8.4% for the cor

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