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Article
Refractive Index Dispersion and Analysis of the Optical Parameters of (PMMA/PVA) Thin Film

Author: Tagreed K. Hamad
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2013 Volume: 16 Issue: 3 Pages: 164-170
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

The optical characteristics of (PMMA/PVA) thin films are investigated by spectrometric measurements. Sample with different percentage are prepared with constant thickness (110 m) using casting technique. The real (n) and imaginary (k) parts of refractive index and dielectric constant of the thin films are determined. Some important parameters of optical absorption, such as the oscillator energy (E0), dispersion energy (Ed), the average value of oscillator strength (S0), wavelength (0) of single oscillator and the ratio carrier concentration to the effective mass (N/m*) have been evaluated. The values obtained for the high frequency dielectric constant through two procedures are in the range of (6.31-7.35) for all ranges of the different concentrations.

تم في هذا البحث دراسة الخصائص البصرية لاغشية بولي مثيل ميثكرلايت (PMMA) وبولي فيانيل الكحول (PVA) بنسب مختلفة(100/0و80/20و40/60و20/80و0/100) بعد تحضيرها بسمك ثابت باستخدام طريقة الصب. حدد معاملي الانكسار والخمود وثابت العزل بجزئيه الحقيقي والخيالي للاغشية. تم حساب بعض الثوابت البصرية المهمة مثل طاقة التذبذب وطاقة التشتت ومعدل قيمة قوة المتذبذب والطول الموجي للمتذبذب المنفرد و نسبة بين تركيزالحاملات الحرة والكتلة الفعالة.سجلت قيم ثابت العزل للتردات العالية من خلال طريقتين وتتراوح قيمتها بين (6.31-7,35) للتراكيزالمختلفة للاغشية المحضرة.


Article
Thickness Effect on the Optical Constants of Poly Methyl Methacrylate (PMMA) Doped by Potassium Iodide

Authors: Wasan A. Musa --- Tagreed K. Hamad --- Mohammed T. Abdul Nabi
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2013 Volume: 16 Issue: 3 Pages: 119-123
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Films of Poly Methyl Methacrylate (PMMA) doped by (1%) Potassium Iodide (KI) have been prepared using casting method at room temperature. Optical properties were investigated for different thicknesses by using spectrophotometeric measurement of absorption reflection transmission in the wave length range (200-800) nm. Both the refractive index (n) and absorption coefficient () were determined for the films. The optical dispersion parameters have been analyzed by single oscillator model. The value of Eo and Ed were found and the other parameters have been determined by Wemple-DiDomenico method

حضرت اغشية بولي مثيل ميثكرلايت ((PMMA المشوبة بملح يوديد البوتاسيوم (KI) بنسبة (1%) بطريقة الصب وفي درجة حرارة الغرفة.درست الخواص البصرية للاغشية المحضرة باسماك مختلفة من خلال قياس الامتصاصية والنفاذية للاطوال الموجية (200-800) nm وحدد معامل الامتصاص () ومعامل الانكسار n)). تم تحليل عوامل التشتت الضوئي باستخدام نموذج التذبذب الاحادي وحددت طاقة التذبذب E0 وطاقة التشتت Edالمطورة وعوامل اخرى بطريقة ويمبل وداي دوميننكو.

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Article
Calibration Free Laser Induced Breakdown Spectroscopy (CF-LIBS) as a tool for Quantitative Elemental Analysis of Iraqi Cement

Authors: Alaa J. Ghazai --- Hussein T. Salloom --- Alaa H. Ali --- Tagreed K. Hamad
Journal: Al-Nahrain Journal of Science مجلة النهرين للعلوم ISSN: (print)26635453,(online)26635461 Year: 2018 Volume: 00 Issue: 1 Pages: 60-68
Publisher: Al-Nahrain University جامعة النهرين

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Abstract

Laser-induced breakdown spectroscopy (LIBS) is a promising atomic emission based elemental analysis technique that has many potential applications for various samples. This paper presents the implementation of calibration free laser induced breakdown spectroscopy (CF-LIBS) approach to identify and determine the concentration of elements in Iraqi cement samples collected from local market. Q-switched Nd: YAG laser with energy laser pulse of 100 mJ and pulse duration of 9 ns is focused on cement pellet surface to generate a plasma spark in air. The plasma emission spectrum was recorded by the spectrometer connected to the fiber optic and resolved spectra were used for identification and quantification of detected elements. The produced plasma temperature was obtained from the Boltzmann plot method while their electron density was determined by Saha-Boltzmann equation. The major elements such as Ca, Si, Al, Fe, Mg and minor Mn, Ti, K and Na elements have been identified and their concentrations calculated based on analysis of the spectrum that contain all information needed to derive the elemental composition of the cement matrix.


Article
The optical properties of Poly methyl methacrylate (PMMA) polymers doped by Potassium Iodide with different thickness
الخصائص البصرية لبوليمرات البولي مثيل مثااكريلات (PMMA)المشوبة بيوديد البوتاسيوم بأختلاف السمك

Authors: Wasan A. Musa وسن علي الطائي --- Mohammed T. Abdul nabi محمد طارق عبد النبي --- Tagreed K. Hamad تغريد خالد الراوي
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2011 Volume: 8 Issue: 2عدد خاص بمؤتمر الفيزياء Pages: 538-542
Publisher: Baghdad University جامعة بغداد

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Abstract

Films of pure Poly (methyl methacrylate) (PMMA) doped by potassium iodide (KI) salt with percentages (1%) at different thickness prepared by casting method at room temperature. In order to study the effect of increasing thickness on optical properties, transmission and absorption spectra have been record for five different thicknesses(80,140,210,250,320)µm. The study has been extended to include the changes in the band gap energies, refractive index, extinction coefficient and absorption coefficient with thickness.

تم تحضير أغشية من البولي مثيل مثااكريلات النقية (PMMA) والمشوبة بملح يوديد البوتاسيوم (KI) بنسبة (%1) بطريقة الصب وفي درجة حرارة الغرفة . لغرض دراسة تأثير السمك على الخواص البصرية سجل طيفي الامتصاصية والنفاذية لخمسة اسماك مختلفة (80,140,210,250,320)µm . امتدت الدراسة لتتضمن تغيرات كل من فجوة الطاقة ،معامل الانكسار،معامل الخمود ومعامل الامتصاص مع زيادة السمك.

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