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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
Mon Mar 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
تصميم نظام مقترح لتخصيص مهام العمل لمحطات العمل وباعتماد الطرق الاجتهادية دراسة حال في الشركة العامة للصناعات الكهربائية
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This research work dealt with the problem of layout the production line of engine of fan roof at the General Company for Electrical Industries (GCEI). It was observed that the assembly line of engine was unstable and subject to severe fluctuations. In addition the execution of tasks at some stations was observed to be very fast while at other stations was slow. This phenomenon resulted into bottlenecks between workstations, idle time, and work in process. The system design was used to assign tasks to work stations according to different heuristics (Ranked Positional weight techniques, longest Task Time, Most following tasks, Shortest tasks time, Least number of following task).

The study revealed that th

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Publication Date
Fri Jun 30 2023
Journal Name
Modern Sport
اثر تمرينات خاصة بأستخدام جهاز المدافع الضوئي المصمم في تنمية بعض القدرات البدنية والاداء المهاري المركب لدى لاعبي كرة اليد
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اتجهت دول العالم الى تسخير جميع الإمكانيات والخبرات والعلوم من اجل الوصول الى مستويات متقدمة في الرياضات المختلفة ويهدف التدريب الرياضي إلى إعداد اللاعبين إعدادا جيدا تكمن مشكلة البحث من خلال خبرة الباحثتان الميدانية ومتابعة تدريبات لاعبي المدرسة التخصصية كرة اليد فقد لوحظ هناك ضعف واضح في الأداء المهاري ولابد من تطوير أوجه الضعف لتحقيق مستوى انجاز افضل . ويهدف البحث اعداد تمرينات خاصة بأستخدام جهاز ا

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Publication Date
Mon Jul 01 2019
Journal Name
مجلة الجامعة العراقية
القياس المحاسبي عن التنمية المستدامة واثره على تقارير الابلاغ المالي نموذج مقترح (دراسة في الشركة العامة للمنتوجات الغازية)
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هدف البحث الى التعرف على القياس المحاسبي عن التنمية المستدامة، وبيان العلاقة بين القياس المحاسبي عن التنمية المستدامة وتقارير الابلاغ المالي، وكذلك بيان أثر القياس المحاسبي عن الاستدامة على تقارير الإبلاغ المالي في الشركة العامة للمنتوجات الغازية، وقد تمحورت مشكلة البحث في بيان أثر عناصر المحاسبة عن التنمية المستدامة، البيئية، والاجتماعية، والاقتصادية، على تقارير الإبلاغ المالي في الشركة العامة للمنتو

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Publication Date
Mon Jan 05 2026
Journal Name
مجلة الجامعة العراقية
معضلة "الإجماع" في ميثاق جامعة الدول العربية وأثرها على إدارة أزمة الخليج الثانية (1990-1991): قراءة قانونية-تاريخية
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الملخص (باللغة العربية) شكّل اجتياح العراق للكويت في 2 آب/أغسطس 1990 اختباراً حاسماً لقدرة جامعة الدول العربية على إدارة الأزمات الإقليمية وصياغة موقف عربي موحّد إزاء انتهاك واضح لسيادة دولة عضو. غير أن أداء الجامعة خلال أزمة الخليج الثانية كشف عن حالة من الشلل المؤسسي والإجرائي، تجلّت في بطء اتخاذ القرار، وتنازع التأويلات حول شرعية الإجراءات، وتوظيف نصوص الميثاق بما أعاق إنتاج قرار عربي حازم وقابل للتنفيذ. تن

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Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
اثر طريقة الملاحظات الصفية باستخدام الحاسوب( كمنشطات عقلية) في التحصيل الدراسي لمادة الفيزياء لدى طالبات الصف الأول المتوسط
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The research aim to know the effect of note–taking by computer method as amentalactivators in achievement of physics subject for the first intermediate class students.

To investigate from aim of the research the research sample was chosen from the first intermediate class students in Al–mutamyzat secondary school for girls. Which belongs to the general administration for the second karkh education which randomly chosen from (9) schools for distinct female students in Baghdad. Then randomly chosen two sections form three about (80) female students at (66.667%) from total sample it’s about (120) female student in the three sections. The randomly chosen too, section (a) to represent experimental group it’s about (41) female

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Exact Stiffness Matrix for Nonprismatic Beams with Parabolic Varying Depth
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In this paper, an exact stiffness matrix and fixed-end load vector for nonprismatic beams having parabolic varying depth are derived. The principle of strain energy is used in the derivation of the stiffness matrix.
The effect of both shear deformation and the coupling between axial force and the bending moment are considered in the derivation of stiffness matrix. The fixed-end load vector for elements under uniformly distributed or concentrated loads is also derived. The correctness of the derived matrices is verified by numerical examples. It is found that the coupling effect between axial force and bending moment is significant for elements having axial end restraint. It was found that the decrease in bending moment was
in the

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Publication Date
Mon Feb 18 2019
Journal Name
Iraqi Journal Of Physics
Transition rates and microscopic effective charges for 16C exotic nucleus
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Publication Date
Tue Dec 11 2018
Journal Name
Iraqi Journal Of Physics
Spectroscopic and structural studies of cadmium oxide thin films prepared by D.C magnetron sputtering
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Cadmium oxide thin films were prepared by D.C magnetron plasma sputtering using different voltages (700, 800, 900, 1000, 1100 and 1200) Volt. The Cadmium oxide structural properties using XRD analysis for just a voltage of 1200 volt at room temperature after annealing in different temperatures (523 and 623) K were studied .The results show that the films prepared at room temperature have some peaks belong to cadmium element along the directions (002), (100), (102) and (103) while the other peaks along the directions of (111), (200) and (222) belong to cadmium oxide. Annealed samples display only cadmium oxide peaks. Also, the spectroscopic properties of plasma diagnostic for CdO thin films were determined and the results show that the el

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Publication Date
Thu Apr 01 2021
Journal Name
Basra Journal Of Science
Preparation and Characterization of Polyvinylpyrrolidone/Multi-walled Carbon Nanotubes Nanocomposite hybrid with Graphene
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In this work, polyvinylpyrrolidone (PVP), Multi-walled carbon nanotubes (MWCNTs) nanocomposite was prepared and hybrid with Graphene (Gr) by casting method. The morphological and optical properties were investigated. Fourier Transformer-Infrared (FT-IR) indicates the presence of primary distinctive peaks belonging to vibration groups that describe the prepared samples. Scanning Electron Microscopy (SEM) images showed a uniform dispersion of graphene within the PVP-MWCNT nanocomposite. The results of the optical study show decrease in the energy gap with increasing MWCNT and graphene concentration. The absorption coefficient spectra indicate the presence of two absorption peaks at 282 and 287 nm attributed to the π-π* electronic tr

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Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Al-nahrain University
DETERMINATION OF SERUM TRACE ELEMENTSMAGNESIUM, COPPER, ZINC, AND SELENIUM IN ASTHMATIC PATIENTS BY ATOMIC ABSORPTION SPECTROPHOTOMETRY
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The aim of this study is to evaluate the levels of trace elements Magnesium (Mg), Zinc (Zn), Copper (Cu), and Selenium (Se) in blood sera of asthmatic patients by Atomic Absorption Spectrophotometry (AAS). The concentrations of Mg, Cu, and Zn have been determined by Flame Atomic Absorption spectrophotometry (FAAS), and Se with flameless Graphite Furnace Atomic Absorption Spectrophotometry (GFAAS). The study involves (55) asthmatic patients as study group and (28) subjects as control from both genders. Serum levels of Mg, Cu, and Se were significantly higher (p<0.001 for all) in patients when compared with healthy subjects, while Zn level was relatively significant (p<0.05). Our observations confirm the efficacy and applicability of (AAS) in

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