Thin films of cobber doped ZnO have been prepared on glass substrate using the Sol-Gel spin coating technique. The effect of doping percentage of Cu to ZnO thin films on the optical properties and optical constants are concluded from absorption and transmission measurements which are obtained by using double beam UV-Visible 1800 spectrophotometer in the wavelength (300-800)nm. It was found that the transmittance increases with increasing the doping percentage (0.01, 0.02,0.03 and 0.04)mol%, while the Absorbance is decreased. The optical energy band gaps have been evaluated and their values seem to be decreased by increasing the doping concentration level in the range (0.01, 0.02, 0.03)mol% followed by a rise with increasing the doping level to 0.04mol%. arabic 17 English 84
Fawzeia Khamis(9-2020)

يستخدم الجادولنيوم كعامل لتحسين تباين صور الرنين المغناطيسي في أغلب حالات التصوير التي يتعذر فيها تحديد نوع الاصابة او طبيعة الورم، ويتميز الجادولنيوم بخصائص مغناطيسية تمكنهُ من التأثير على زمن الاسترخاء للبروتونات الموجودة في النسيج. مما يسبب في زيادة شدة الاشارة أو تقليلها حسب نوع الصورة. ويهدف هذا البحث لدراسة العلاقة بين زيادة شدة الإشارة في أنسجة الدماغ بعد استخدام الجادولنيوم وبعض البارامترات المحسوبة إحصائيا عن طريق معالجة صور الرنين باستخدام طريقة مصفوفة التكرارات للمستويات الرماديةGrey Level Co-occurrence Matrix. وحيث أن زيادة شدة الاشارة تكون نتيجة تقصير زمن الاسترخاء في الصورة المرجحة T1. تم دراسة إحدى أهم العوامل المؤثرة في الإشارات المكونة لصورة الرنين المغناطيسي وهو زمن الاسترخاء، وتم توضيح تأثير زمن الاسترخاء الطولي T1 والعرضي T2على تباين انسجة الدماغ في صور الرنين، ثم قمنا بمعالجة صور مرجحة لزمن الاسترخاء الطولي (T1- Weighted) أُخدت في المقطع المحوري (axial)، هذه الصور لحالات مصابة بأورام في الدماغ تم فيها استعمال الجادولنيوم. اهتمت هذه الدراسة بتحديد العلاقة بين زيادة شدة الاشارة في الانسجة المصابة وبعض البارامترات المحسوبة احصائياً عن طريق المعالجة. كما تم دراسة مدى استجابة الانسجة الطبيعية للجادولنيوم وتم مقارنتها بالأنسجة المصابة. واثبتت النتائج ان زيادة شدة الإشارة بعد استعمال حُقن الجادولنيوم في المناطق التي تحتوي على أنسجة مصابة يزيد في قيم البكسل المكونة لصورة الرنين. وبينت النتائج أن زيادة شدة الإشارة تتناسب مع تلك البارامترات المحسوبة كُلا حسب طبيعة النسيج. Abstract Gadolinium used as a factor to improve the contrast magnetic resonance images, in most cases of imaging that can't determine the type of lesion or tumor. Gadolinium is characterized by magnetic properties of being able to influence the relaxation time of protons in tissue. This would cause an increase or decrease in the intensity of the signal depending on the type of image. This research aims to study the relationship between the increases in signal intensity in the brain tissue by using Gadolinium. Statistically method would be implied after resonance images are processed, using a matrix method of iterations for gray level, it is know as Grey Level Co-occurrence Matrix. In T1-weighted image, an increase in signal intensity is duo to shorting of relaxation time. Relaxation time which is considered as one of the most important aspect effecting the signal component from MRI images was studied in depth. Also, the effect of relaxation time longitudinal T1 and transverse T2 on the variation of brain tissue were clarified. Then, T1-weighted axial images were processed. Images used in this work were taken from patients with brain tumor, and contrast agent (Gadolinium) was used to enhance them. This study focused on identifying the relationship between the increase in signal intensity in the lesion tissues and statistically calculated parameters. The respond of normal and effected tissues the Gadolinium were compared. The study shows that an in increases in pixel intensity, after contrast is introduced, in areas with infected tissue. Also, the results indicate that signal intensity commensurate with those calculated parameters.
تهاني عياد صالح العباني (2014)

Thermoluminescence (TL) of pure and Eu3+ and Dy3+ doped synthesis quartz was synthesized and their ion beam and thermoluminescence properties were investigated. The as prepared, doped and co-doped quartz and the effects of imparting 2 Gy beta dose and 2MeV 4He+ ion beam irradiation is investigated. The basic model proposed and can explain our observations is that, the dominant signals from the as prepared material arise from the incorporation of the transitions within the RE dopants enhanced by the intensity from the intrinsic or host defect sites within the synthesis quartz network. The complex shape TL glow curves indicate that irradiation causes major distortions to the lattice with the incorporation of extrinsic impurities and RE doping processes, induce perturbations and alter the energy levels pattern of the free ions and assigned transitions probabilities in a manner that that depends on the dopants, their concentrations and the host material. The larger Eu ions stabilize the emission more than that of the Dy ions. The TL peak temperatures are commonly correlated via charge transfer processes and scale with the ions size, in such a manner that the close proximity (or shallow traps) allows lower temperature electron release, whereas the more distant variants (deep traps) are less distorted, but are still able to couple to the higher energy orbitals of the Eu ions. arabic 26 English 120
Fawzeia Khamis(10-2020)