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Article
Dispersion Parameters of Copper Sulphate Doped PMMA
معلمات التفريق للبولي مثيل ميثاكريلات المشوب بكبريتات النحاس

Authors: Zainab Al-Ramadhan زينب الرمضان --- Nadir Fadhil Habubi نادر فاضل حبوبي --- Sami Salman Chiad سامي سلمان جياد
Journal: Baghdad Science Journal مجلة بغداد للعلوم ISSN: 20788665 24117986 Year: 2010 Volume: 7 Issue: عدد خاص بمؤتمر العلمي النسوي 1 Pages: 162-167
Publisher: Baghdad University جامعة بغداد

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Abstract

Films of PMMA and copper sulphate doped PMMA have been prepared by casting method. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm in order to calculate, single oscillator energy, dispersion energy, average oscillator strength, the refractive index at infinite wavelength, M-1 and M -3 moments of the optical spectra, it was found that all these parameters were effected by doping.

حضرت أغشية PMMA و PMMA المشوب بكبريتات النحاس (CuSO4) بطريقة الصب. سجل طيفي النفاذية والامتصاصية لمدى الطول الموجي (300-900) nm. وذلك لغرض حساب طاقة المتذبذب المفردة، طاقة التفريق، معدل قوة المتذبذب، ومعامل الانكسار عند الطول الموجي (مالانهاية) وكذلك العزوم M-1 و. M -3 لقد وجد بان كافة المعلمات قد تاثرت بالتشويب.


Article
Determination the dispersion parameters and urbach tail of iron chromate doped PMMA films
تحديد معلمات التفريق وذيل اورباخ لاغشية بولي مثيل ميثا اكريلات المشوبة بكرومات الحديد

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Abstract

Films of pure Poly (methyl methacrylate) PMMA and Iron chromate doped PMMA have been prepared using casting method. Transmission and absorptance spectra have been recorded in the wavelength range (300-900) nm, in order to calculate, single oscillator energy, dispersion energy proposed by Wemple - DiDomenico model, average oscillator strength, average oscillator wavelength. The refractive index data at infinite wavelength which was found to obey single oscillator model which was found to increase from 2.27-2.56 as the doping percentage increase. The decreasing in the optical energy gap which was found according to Tauc model were (3.74-3.63) eV , is in good agreement with that obtained by wimple-DiDomenico model. The inverse behavior compared with the value of the energy gap were obtained for Urbach energies by increasing from (266-308) meV upon doping.

حضرت اغشية من البولي مثيل ميثا اكيلات النقي والمشوب بكرومات الحديد بطريقة الصب. سجل طيفي النفاذية والامتصاصية في مدى الاطوال الموجية (300-900) nm لغرض حساب طاقة المتذبذب المفردة ، طاقة التفريق المقترحة من قبل انموذج Wemple – DiDomenico ، متوسط القوة للمتذبذب . لقد وجد بان بيانات معامل الانكسار للطول الموجي اللانهائي تخضع لانموذج المتذبذب المفرد والتي وجد بان قيمها تزداد من 2.27 الى 2.56 بازدياد نسبة التشويب . تيبن ان النقصان الحاصل في فجوة الطاقة (3.63-3.74) eV وفقا لانموذج Tauc ، قد اتفقت مع النتائج المستحصلة من انموذج Wemple – DiDomenico. تم الحصول على سلوك معاكس لتغير قييم فجوة الطاقة عند حساب طاقة اورباخ والتي ازدادت نتيجة التشويب (308-266) meV .


Article
Preparation of Chloro Penta Amine Cobalt (III) Chloride and Investigate its Influence on the Structural Properties and Acoustical Parameters of Polyvinyl Alcohol

Authors: Nada K. Abbas ندى كاظم عباس --- Majeed Ali Habeeb مجيد علي حبيب --- Alaa J. Kadham Algidsawi الأء جواد كاظم
Journal: Journal of Kufa - physics مجلة الكوفة للفيزياء ISSN: 20775830 Year: 2015 Volume: 7 Issue: 2 English and Arabic Pages: 81-96
Publisher: University of Kufa جامعة الكوفة

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Abstract

Chloro penta amine Cobalt (III) Cloride [Co(NH3)5Cl]Cl2 was prepared then characterized by FTIR and XRD . The obtained results indicated the formation of Orthorhombic [Co(NH3)5Cl]Cl2 nano particles of ≈ 28.75 nm size .Polymeric films based on polyvinyl alcohol PVA doped with Chloro penta amine Cobalt (III) Cloride [Co(NH3)5Cl]Cl2 at different weight percent ratios were prepared using the solvent cast technique. The structural properties of these polymeric films were examined by XRD, FTIR and SEM studies. The complexation of the additive with the polymer was confirmed by FTIR and SEM studies. The XRD pattern revealed that the amorphousicity of PVA polymer matrix increased with raising the [Co(NH3)5Cl]Cl2 content. Ultrasonic pulse technique of variable frequency (25, 30, 35 and 40) kHz were performed to study the influence of ultrasonic frequency on the mechanical properties of PVA/ [Co(NH3)5Cl]Cl2 composite. Some properties such as ultrasonic velocity, acoustic impedance ,bulk modulus and transmittance and relaxation amplitude were found to be decreasing with frequency while absorption coefficient and compressibility were increasing with frequency .Results showed that ultrasonic wave made degradation to the randomly coiled polymer chains ,when ultrasonic frequency increase there were more degradation that increasing the number of un-tied chains as a result of absorbing composite ultrasonic waves ,for this reason it could be pointed that PVA/[Co(NH3)5Cl]Cl2 composite as a good ultrasonic absorber. It was found that there was significant relationship between ultrasonic velocity and material properties


Article
Mechanical Properties of 7075 Aluminum Alloy Matrix/Al2O3 Particles Reinforced Composites

Authors: H. J.M. Al-Alkawi --- A.A. Al- Rasiaq --- M.A.A. Al- Jaafari
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2017 Volume: 35 Issue: 3 Part (A) Engineering Pages: 239-245
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

7075 Aluminum alloy metal matrix composites (


Article
Effect Of Thermal Annealing On The Optical Properties Of Thin Films Of Polymer Blend (PMMA:PVC:PS)

Author: Ali N. Sabbar 1*, Karar M.Talib2, and Hassan T. Badh1
Journal: Almuthanna Journal of Pure Science (MJPS) مجلة المثنى للعلوم الصرفة ISSN: 22263284 Year: 2018 Volume: 5 Issue: 1
Publisher: Al-Muthanna University جامعة المثنى

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Abstract

In this paper, we report upon preparation and optical properties of the polymer blend(50%PMMA:25%PVC:25%PS) thin films. The thin films have been prepared with specific ratios using the castingtechnique at normal weather conditions. The films were subjected to heat treatment in varying temperatures for threehours. The results showed that increase thermal annealing temperature leads to decrease values of the direct and indirectenergy gap, but increase the extinction coefficient and optical conductivity. The refractive index, real and imaginarydielectric constants showed a heterogeneous behaviour. Thermal annealing by 80 oC and up leads to deformation thethin films.


Article
Effect of Polystyrene Film Thickness on Some Optical Parameters
تأثير سمك اغشية البولي ستايرين على بعض المعلمات البصرية

Authors: Nadir Fadhil Habubi --- Sami Salman Chiad --- Obaida Amer Abdul Hussein
Journal: Diyala Journal For Pure Science مجلة ديالى للعلوم الصرفة ISSN: 83732222 25189255 Year: 2010 Volume: 6 Issue: 1 Pages: 314-320
Publisher: Diyala University جامعة ديالى

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Abstract

Films of polystyrene of different thicknesses have been prepared by casting method. Transmission and absorption spectra have been recorded in order to study the effect of increasing thickness on some optical parameters such as transmittance absorptance, refractive index, extinction coefficient, and absorption coefficient, real and imaginary parts of dielectric constant. This study reveals that all these parameters affect by increasing the thickness.

حضرت أغشية البولي ستايرين بأسماك مختلفة باستعمال طريقة الصب. سجل طيفي النفاذية والامتصاصية وذلك لغرض دراسة بعض المعلمات البصرية مثل: النفاذية، الامتصاصية، معامل الانكسار، معامل الخمود، ثابت العزل بجزيئيه الحقيقي والخيالي. توصلت هذه الدراسة الى أن لسمك الغشاء تأثير على كافة المعلمات البصرية


Article
Mechanical Properties of Al 6061/Al2O3 Nanocomposite by Stir Casting

Authors: Hussain J.Alalkawi --- Huda A. Al-Salihi
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2018 Volume: 36 Issue: 3 Part (A) Engineering Pages: 328-332
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Present work deals with the examination of the mechanical properties of Al 6061 composites, which were successfully fabricated by stir casting technique and then reinforced by using different percentages of Al2O3 nanoparticles up to 10 wt%. The required samples were carefully prepared. Evaluation of the mechanical properties such as hardness, yield tensile stress and ultimate tensile stress were effectively obtained at various percentages of Al2O3 nanoparticles .It was found that the mechanical properties of 6061 /Al2O3 nanoparticles are critically influenced by the concentrations of the reinforced Al2O3 nanoparticle, since there was a substantial enhancement in the mechanical properties, as the fractions of Al2O3 nanoparticles increased. This improvement in the mechanical properties was attributed to the uniform distribution of reinforcement nanoparticles as well as the grain refinement of aluminum matrix with minimal porosity.


Article
Effect of Thickness on The Optical Parameters of PVA:Ag
تأثير السمك على المعاملات البصرية لبولي فانيل الكحول المشوب بالفضة (PVA:Ag

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Abstract

Poly(vinyl alcohol) doped Ag films with different thicknesses were prepared by castingmethod. The thickness of the prepared films were 10, 20, 30,and 40 μm. Transmission andabsorption spectra have been recorded in order to study the effect of increasing thickness onsome optical constants such as transmittance, reflectance, absorption coefficient, refractiveindex, extinction coefficient, and real and imaginary parts of dielectric constant. This studyreveals that all these parameters affect by increasing the thickness.

حضرت اسماك مختلفة من أغشية بولي فانيل الكحول المشوب بالفضة وهذه الاسماك كانت بحدود10, 20, 30,and 40 µm وان طيف النفاذية قد سجل لدراسة تاثير زيادة السمك على بعض الخواص البصرية المتمثلة بمعامل الامتصاص والنفاذية والانعكاسية ومعامل الانكسار ومعامل الخمود وثابت العزل بجزئيه الحقيقي والخيالي وان هذه المعاملات تتأثر بزيادة السمك.


Article
Optical properties of polyvinyl alcohol (PVA) films doped with CoCH3COOH salt
الخصائص البصریة لأغشیة بولي فنایل الكحول المشوبة بملح خلات الكوبلت

Authors: Sabah A. Salman صباح أنور سلمان --- Zainab A. Al-Ramadhan زینب عبد السلام الرمضان --- Zainab F. Nazal زینب فالح نزال
Journal: Diyala Journal For Pure Science مجلة ديالى للعلوم الصرفة ISSN: 83732222 25189255 Year: 2014 Volume: 10 Issue: 3 - part 1 Pages: 39-49
Publisher: Diyala University جامعة ديالى

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Abstract

The optical characteristics of polyvinyl alcohol (PVA) films doped with different concentrations (0, 1, 3, 5, 7 and 10 wt%) of CoCH3COOH salt powder were studied. The optical transmittance (T%) in the wavelength range (190-1100) nm of films deposited by usingsolvent casting method was measured. The results show indirect allowed transitions, and the optical band gap of the films decreases with increasing CoCH3COOH content. Optical parameters such as absorption coefficient, refractive index, extinction coefficient and the real and imaginary parts of the dielectric constant of the films were calculated as a function of doping .

تم في هذا البحث دراسة الخصائص البصرية لأغشية بولي فنايل الكحول (PVA) المشوبة بتراكيز مختلفة(0, 1, 3, 5, 7 and 10 wt%) من مسحوق ملح خلات الكوبلتCoCH3COOH . قيست النفاذية البصرية (T%) بمدى الأطوال الموجية nm(1100-190) للأغشية المرسبة بطريقة الصب. أظهرت النتائج انتقالات غير مباشرة مسموحة وان فجوة الطاقة البصرية للأغشية قد قلت بزيادة تركيز خلات الكوبالت. المعلمات البصرية مثل معامل الامتصاص، معامل الانكسار، معامل الخمود، ثابت العزل بجزئيه الحقيقي والخيالي قد حسبت كدالة للاشابة.


Article
Effect of Kaolin Clay Concentration and Irradiation on the Electronic Transitions of Polyvinyl Alcohol Films
تأثير تركيز الكؤلين والتشعيع على الأنتقالات الألكترونية لأغشية بولي فنايل الكحول

Author: Hadi Ahmed Hussin هادي أحمد حسين
Journal: Diyala Journal For Pure Science مجلة ديالى للعلوم الصرفة ISSN: 83732222 25189255 Year: 2014 Volume: 10 Issue: 4 Pages: 14-24
Publisher: Diyala University جامعة ديالى

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Abstract

Pure and (1 and 3 wt%) kaolin doped PVA films were synthesized by solution casting method, and exposed to 60Co--rays, activity 2µCi for two weeks, The optical characterizations of the films were carried out using UV-Vis transmittance spectrophtometer in the wavelength range 300–900 nm. The results show that in the visible region the transmittance of the films increases as the kaolin concentration increase clearly as comared with the same film before irradiation. The dominant transmittance band of UV region increases after irradiation while the reverse is the case with the reflectance. Also results indicates that PVA films have an indirect band gap that decreased from 3.7 to 3.55 eV as the doping concentration increases to 3wt%. Also the energy band gap of the irradiated films appeared to be decreased from 3.9 eV down to 3.4 eV.

حضرت أغشية البولي فينايل الكحول غير المشوبة والمشوبة (1%, 3%) كاولين بطريقة الصب , وعرضت لأشعة كاما الناتجة من الكوبلت – 60 بنشاطة 2µCi لمدة اسبوعين, تم دراسة الخصائص البصرية باستخدام مطياف الأشعة فوق البنفسجية المرئية لمدى الاطوال الموجية 300 – 900 نانومتر. أثبتت النتائج ان النفاذية في المنطقة المرئية تقل بزيادة تركيز الكاولين عند مقارنتها مع الأغشيىة غير المشوبة. تزداد حزمة النفاذية المهيمنة في منطقة فوق البنفسجية بعد التشعيع بينما يحدث العكس في حالة الانعكاسية. كذلك فان النتائج تشير الى ان أغشية (PVA) ذات انتقال غير مباشر ويقل من 3.7 الى 3.55 eV بازدياد نسبة 3% . ان فجوة الطاقة المباشرة للأغشية المشععة تشير الى تناقص الفجوة من 3.9 الى3.4 eV .

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