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Article
Effects of Temperature and Concentration on Spectroscopic Behaviors of Laser Dye

Authors: Bahaa T. Chiad --- Omar S. Shafeq
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 1 Pages: 35-39
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, the fluorescence spectra of an organic lasing dye were recorded at different temperatures and doping concentrations. Results showed that when the donor concentration fixed and the acceptor concentrations varies for two temperatures (room and low) and for both solvents (ethanol and methanol) used in this work, the peaks of emission of donor and acceptor show a small blue shift. However, this blue shift increases with increasing the acceptor concentrations against donor concentration.


Article
Effects of Temperature and Concentration on Spectroscopic Behaviors of Laser Dye
تأثيرات درجة الحرارة والتركيز على السلوكيات الطيفية لصبغة الليزر

Authors: Bahaa T. Chiad --- Omar S. Shafeq
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2017 Volume: 13 Issue: 1 Pages: 35-39
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, the fluorescence spectra of an organic lasing dye were recorded at different temperatures and doping concentrations. Results showed that when the donor concentration fixed and the acceptor concentrations varies for two temperatures (room and low) and for both solvents (ethanol and methanol) used in this work, the peaks of emission of donor and acceptor show a small blue shift. However, this blue shift increases with increasing the acceptor concentrations against donor concentration.


Article
Effect of Silver Nanoparticles on Fluorescence Spectra of C480 dye

Authors: Sarmed S. AL-Awadi --- Ruwaida T. Shbeeb --- Bahaa T. Chiad
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2018 Volume: 59 Issue: 1C Pages: 502-509
Publisher: Baghdad University جامعة بغداد

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Abstract

This work aim to study the effect of silver nanoparticles on fluorescence intensity of Coumarin 480 dye by using the sandwiches technique where AgNP layer had been separated from C480 layer by different type of materials such as silica, PMMA polymer and PVA polymer layer. Silver nanoparticles had been prepared by the chemical reduction method so the AgNP layer coating had been done by hot rotation liquid method. The optical properties of prepared samples had been tested by using UV-VIS absorption spectrophotometer and Fluorescence spectrophotometer. Morphology, average size and the structure of nanoparticles were estimated using AFM, SEM testes

Keywords


Article
A Study of Heating Effect on the Structural and Optical Absorbance of Olive Oil

Authors: Mays K. Ali --- Mohammed Sh. Essa --- Bahaa T. Chiad
Journal: Iraqi Journal of Science المجلة العراقية للعلوم ISSN: 00672904/23121637 Year: 2018 Volume: 59 Issue: 2A Pages: 670-675
Publisher: Baghdad University جامعة بغداد

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Abstract

In this study, the number of times of heating of olive oil was studied. For the different refineries, the study was conducted using a temperature of 300K and for several times to determine the validity of the olive oil which is used for frying purposes after it was used for more than once times. It was found that there were significant changes in the behavior of the photophysical behavior like absorption and emission; there are changes in the nature and composition of the olive oil molecule, which makes it not useful for human use. The number of heating times was ten. The heating times also showed significant changes in the nature of the oil, such as color, taste, density, and smell.

Keywords

olive oil --- frying --- cooking --- spectroscopic


Article
study the optimum conditions of synthesis AgNP by chemical reduction method
دراسة الظروف القياسية لتحضير جسيمات الفضة النانوية بطريقة الاختزال الكيميائي

Authors: Bahaa T.Chiad --- Natheera.A.Ali --- Zainab.S. Sadik --- Sarmed. S.AL-Awadi
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2013 Volume: 11 Issue: 4 Pages: 40-46
Publisher: Kerbala University جامعة كربلاء

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Abstract

In this paper, silver nanoparticles had been prepared by chemical reduction method. Many tests had been done to it such as UV-Visible spectrophotometer, XRD, AFM&SEM test. finally an attempt had been done to get the optimum condition to control the grain size of silver Nanoparticles by variation the heating period and other parameters which has an effect in silver Nanoparticles synthesis process. in this method we can get a silver nanoparticles in the size range from 52 to 97 nm.

تضمنت الدراسة الحالية تحضير جسيمات الفضة النانوية بطريقة الاختزال الكيميائي. عدة قياسات اجريت للنماذج المحضرة كقياس مطيافية الاشعة تحت الحمراء وفوق البنفسجية لقياس الامتصاصية بالاضافة الى حيود الاشعة السينية ومقياس القوى الذرية فضلا عن استخدام المجهر الالكتروني الماسح.فضلا عن كل هذا يهدف هذا البحث الى اجراء دراسة تفصيلية لدراسة امكانية السيطرة على حجم جسيمات الفضة النانوية من خلال دراسة المتغيرات التي من الممكن ان تؤثر على عملية التحضير كتغيير زمن الاختزال وباقي المتغيرات الاخرى .في هذه الطريقة من الممكن ان نحضر جسيمات فضة نانوية تتراوح احجامها بين 52 الى 97 نانومتر .

Keywords


Article
Structural Characteristics of γ-Al2O3 Nanoparticles Prepared by Laser-Assisted Spray Pyrolysis Technique

Authors: Bahaa T. Chiad --- Zainab S. Sadiq --- Dunia K. Mahdi --- Fatin H. Mohammed
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2015 Volume: 11 Issue: 2 Pages: 29-32
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

This work describes laser-assisted spray pyrolysis (LASP) technique developed to deposit nanoparticles coatings with controllable particles size. In this process, droplets of a precursor formed by atomizer are injected into a deposition chamber using SF6 as a carrier gas. The study were focused once on the effect of variation of the concentration of precursor solution on particle size of Al2O3 samples, and the other effect of variation of SF6 gas flow rate on the particle size of the samples. Decreasing of precursor concentration (0.25-0.1M) caused to decrease of the particle sizes with increase in density of Al2O3 nanoparticles. Decreasing of SF6 gas flow rate (4.5-2.5)L/min caused to decrease of the particle sizes with increase in density of Al2O3 nanoparticles and homogeneity of the samples.


Article
Synthesis and Study of Nanostructure Fe2o3 Film by Laser Assisted Spray Pyrolysis

Authors: Bahaa T. Chiad --- Zainab S. Sadik --- Dunia K. Mahdi --- Fatin H. Mohammed
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2015 Volume: 18 Issue: 3 Pages: 62-66
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Films of hematite (α-Fe2O3) were deposited by using laser assisted spray pyrolysis technique (LASP). The films were deposited on heated substrates with temperature 400̊C, once with using laser and other without laser, Structural analysis, using X-ray diffraction, verified the phase of the films and revealed that the films had a polycrystalline structure composed of nano-crystallites. Atomic force microscopy indicated that the films which deposited by laser assisted had smooth surface with smallest lateral grain size compared with the films deposited without laser, where the average grain size for the film deposited without laser about 146nm,while the average grain size for the film deposited with laser about 77nm.

رسبت اغشية من الهيماتايت (-Fe2O3α) باستعمال تقنية الانحلال الحراري بمساعدة الليزر. الافلام المترسبة على ركيزة بدرجة حرارة 400ͦ م, مرة باستعمال الليزر والاخرى بعدم استعمال الليزر. التحليل الهيكلي باستعمال حيود الاشعة السينية كشف ان طور الافلام لها بناء هيكلي متعدد التبلور مكون من بناء نانوي, مجهر القوة الذرية (AFM) يشير الى ان الاغشية المترسبة بمساعدة الليزر لها سطح املس مع حجم حبيبي اصغر مقارنة بالافلام المترسبة بدون الليزر, حيث ان معدل الحجم الحبيبي للغشاء المترسب بدون الليزر حوالي 146 نانومتر, بينما معدل الحجم البلوري للغشاء المترسب بمساعدة الليزر كان 77 نانو متر.


Article
Key Mechanisms of Low-Pressure Glow Discharge in Magnetized Plasmas
الاليات الاساسية للتفريغ التوهجي ذي الضغط الواطيء في البلازما الممغنطة

Authors: Oday A. Hammadi --- Mohammed K. Khalaf --- Firas J. Kadhim --- Bahaa T. Chiad
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 3 Pages: 3-10
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this article, the key mechanisms of glow discharge in low-pressure gas mixtures were presented and discussed. The particle motions – mainly collisions – in discharge plasma those considered in most applications of plasma were presented. The regions of glow discharge were identified and their main characteristics were highlighted. These mechanisms were supported by experimental results obtained from a homemade dc plasma sputtering system. The experimental parameters, such as inter-electrode distance, using magnetrons and adding nitrogen to the gas mixture, and their effects on the Paschen’s curve of glow discharge were introduced.


Article
Langmuir Probe Diagnostics of Low-Pressure Glow Discharge Plasma Using Argon-Nitrogen Mixtures
التشخيص باستخدام مجس لانجمور لبلازما التفريغ ذي الضغط الواطئ باستخدام خلائط غازي الاركون والنتروجين

Authors: Bahaa T. Chiad --- Oday A. Hammadi --- Firas J. Kadhim --- Mohammed K. Khalaf
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 3 Pages: 17-26
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, experimental results on Langmuir probe diagnostics of low-pressure glow discharge plasma using argon-nitrogen mixtures are presented. The effect of variation in working pressure on the current-voltage characteristics of Langmuir probe diagnostics in unmagnetized glow-discharge plasma was introduced. The current-voltage characteristics of Langmuir probe diagnostics in glow-discharge plasma were studied at working pressure of 0.7mbar and three different cases (no magnetron, using one magnetron at the cathode, and using dual magnetrons). Similarly, the current-voltage characteristics of Langmuir probe in glow-discharge plasma at three different positions of the Langmuir probe inside plasma volume were presented. The variation of electron temperature and density in plasma with working gas pressure at the center point between the electrodes when dual magnetrons were used was determined. As well, the effect of mixing nitrogen with argon on the Langmuir probe characteristics at total working pressure of 0.7mbar and inter-electrode distance of 4cm was studied.


Article
Preparation of Highly Pure Nanostructures by Reactive DC Magnetron Sputtering Technique
تحضير تراكيب نانوية عالية النقاوة باستخدام تقنية الترذيذ التفاعلي المستمر

Authors: Firas J. Kadhim --- Oday A. Hammadi --- Mohammed K. Khalaf --- Bahaa T. Chiad
Journal: Iraqi Journal of Applied Physics المجلة العراقية للفيزياء التطبيقية ISSN: 18132065 23091673 Year: 2016 Volume: 12 Issue: 3 Pages: 27-34
Publisher: iraqi society for alternative and renewable energy sources and techniques الجمعية العراقية لمصادر وتقنيات الطاقة البديلة والمستجدة

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Abstract

In this work, metal oxide and nitride nanostructures were prepared by reactive dc magnetron sputtering technique. These nanostructures were synthesized from metal oxide such as NiO and nitride such as Si3N4 for functional materials applications. The prepared nanostructures were diagnosed by x-ray diffraction (XRD) patterns and Fourier-transform infrared (FTIR) spectroscopy. The results showed that the prepared nanostructures are highly pure, which is ascribed to the featured characteristics of magnetron sputtering technique for such purposes.

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