خلال الربع الأخير من القرن العشرين ، شهد الاقتصاد العالمي تحولا في مختلف المجالات التجارية والتكنولوجية والمالية التي غيرت هيكلها وأنتجت وضعا جديدا يتمثل بشكل رئيس في زيادة حركة رأس المال الأجنبي والتوسع السريع للإنتاج الدولي والتجارة بالإضافة إلى التطور التكنولوجي الهائل ونقل التكنولوجيا ، مما أدى إلى هوس الدول بالمنافسة على المستوى العالمي والسعي لدخول الأسواق الدولية وتحسين قدرتها التنافسية. وت
... Show MoreThis project aims to fabricate nanostructures (AgNPS) using the electrical exploding wire (EEW) technique using Rhodamine 6G dye as the probe molecule, investigate the effect of AgNPS on the absorption spectra and surface-enhanced Raman scattering (SERS) activities, and advance using porous silicon as an active substrate for surface-enhanced Raman scattering (SERS). X-Ray diffraction (XRD) was used to investigate the structural properties of the nanostructures (AgNPs). Field emission scanning electron microscopy (FE-SEM) was used to investigate surface morphology. A double beam UV-Vis Spectrophotometer was used to analyze the mixed R6G laser dye(of concentration 1x M) absorption spectra with the nanostructures AgNPS (of concentra
... Show MoreIn this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
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