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العنوان
Preparation of some polymeric materials embedded in nano-structured oxides using sol gel technique for industrial applications \
المؤلف
Ahmed, Eman Helmy.
هيئة الاعداد
باحث / إيمان حلمي احمد
مشرف / أحمد إسماعيل هاشم
مشرف / مجدي محمد حسن ايوب
مشرف / إيناس كمال بطيشة
تاريخ النشر
2019.
عدد الصفحات
270 p. :
اللغة
الإنجليزية
الدرجة
الدكتوراه
التخصص
الكيمياء
تاريخ الإجازة
1/1/2019
مكان الإجازة
جامعة عين شمس - كلية العلوم - الكيمياء
الفهرس
Only 14 pages are availabe for public view

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Abstract

New classes of phosphosilicate nano-composites doped with )1-3.5( mol % of Erbium ions and several polymeric materials as (hyperbranched, dendritic and chitosan polymers) which were successfully prepared and developed for planar optical waveguide sensor applications. The optical planar waveguide sensor is used for transmitting the light from one point to another and processing the light propagation. This property has been used in energy applications such as data communication (transferring information) in submarines co-axial cables under sea and sonar technology such as medical speculum. Using rare earth erbium ions material permits the high population inversion that is substantially involved in the planar waveguide sensors. It can emit light at 1.54 µm due to the 4f shell transition from the first excited state 4I 13/2 to the ground state 4I 15/2 of the Er3+ ions. A 1.54 µm signal travelling through the erbium doped waveguide will then induce stimulated emission from the first excited state to the ground state, resulting in signal amplification. The most frequent challenges in the present device are the higher refractive index, transparency and the higher thickness bigger than 1µm of the prepared thin film device to meet the demands for higher bandwidth planar optical waveguide communication systems. The surface properties of amorphous phosphosilicate, which is considered to be an oxide adsorbent, depend on the presence of silanol groups. The OH groups act as centers of molecular adsorption during their specific interaction with adsorbents capable of forming a hydrogen bond with the OH groups such as hyperbranched polyamido amine and dendritic polymer grafted onto chitosan surface. Both previously mentioned polymeric materials were embedded into phosphosilicate activated with Er3+ ions via chemical interaction and chemical bond formation for the first time worldwide. In this way the removal of large number of OH groups was successfully achieved in phosphosilicate nanocomposites via long term thermal modification. While, for the polymeric hybrid optical device via chemical interaction formation.
In this way, it could be concluded that all the needed parameters to meet planar optical waveguide applications such as higher transparency, refractive indices, thickness and 1.54 µm signal emission at near infrared region were successfully achieved. It was worthy to mention that the average thickness for phosphosilicate compounds was averaged from 1.1 to 1.7 µm. However, it was averaged from 3.7 to 4.3 µm for the polymeric/ Phosphosilicate planar waveguide sensor.
While, the refractive indices for phosphosilicate compounds were ranged from 1.69 up to 1.75 compared to SiPhHYPEr3+, SiPhDEr3+,and SiPh5Cs2Er3+ which were 1.829, 1.9014, 1.774, respectively.
These facts supported that these polymeric nanocomposites devices are suitable candidates for planar optical waveguide energy sensors applications.