Abstract In this work, study was performed using Amorphous polymer – based composites consisting of polystyrene (PS) and carbon black (CB) . Five samples have been prepared with different weight percentage which are (0%CB+100%PS) , (5%CB+95%PS) , (15%CB+85%PS) , (25%CB+75%PS) and (35%CB+65%PS) . The electrical properties have been studied for these samples as follows : Electrical conductivity , relative dielectric constant and the dielectric loss tangent were measured at alternating electric field in temperature range between (30C°) and (60C°) and at four different constant frequencies (100HZ, 1KHZ, 10KHZ and 100KHZ ) . It is noted that the highest value of alternating electrical conductivity at (30C°) is for the sample of composition (25%CB+75%PS) which was (1.25x10 S/m ) and the highest value at temperature (60C°) was for same sample with value of (3.2x10 S/m ) , it should be noted that in general the electrical conductivity increases as the temperature increases where this result shows the behaviour of semiconductors. The relative dielectric constant in the pure sample (0%CB+100%PS) and the other samples with low percentage of carbon black increases as the temperature increases however it decreases as frequency increases. And the samples with higher percentage of carbon black which are (25%CB+75%PS) and (35%CB+65%PS) it was noted that the relative dielectric constant decreases as temperature increases. The lowest value was (1.26) at temperature (30C°) and frequency (10KHZ) for the sample with composition of (15%CB+85%PS), while the highest value at same temperature is (410.2) at (100HZ) for the sample with composition of (25%CB+75%PS), for the relative dielectric constant the highest result it was for the sample (5%CB+95%PS) at (607) at (100HZ) and (45C°). The dielectric loss tangent increases as the carbon black increases in all samples and it was found that the temperature influence will be at high percentage of the carbon black where the temperature of (55C°) the dielectric loss tangent increased to the highest value (1.2X10 ) for the sample of composition (35%CB+65%PS). at the high level of the carbon black it was found that the dielectric loss tangent decreases as the frequency increases.
عادل محمد التميمي (2013)

: Neodymium isotopes (Z=60) lie in the traditional rotational to transitional-spherical region that occurs at the range of deformed nuclei. The identity of 146−158 Neodymium nuclei have been determined in framework of Interacting Boson Model-2, a simulation program with NPBOS has been used to obtain the theoretical energy levels for Neodymium isotopes. The parameters of the best fit to the measured data are determined. The energy positive parity bands of those isotopes were calculated using (IBM-2) and then it compared with the experimental values. The mentioned isotopes ratios (E(4_1^+))/(E(2_1^+)) have calculated and also E-GOS curves (( E_γ)/I) have drawn as a function of the spin I, to classify symmetry of the nuclei. The electromagnetic transition probabilities B(E2) of these nuclei was calculated as well, where a good agreement for low lying energy states were obtained between experimental results and theoretical calculations. The results have been shown that the interested nuclei 152-158Nd have rotational characters SU (3), and O (6) symmetry is substantiated for 146-148Nd, as well as the critical point X (5) has been determined for 150Nd isotope.
D. Nasef, Najat S. Eshaftri, Ayad E. Ezwam, Suad M. Bogrin, Asma A. Elbendag, Sadiq M. El-kadi(12-2021)

إستخدمت البيانات المتوفرة من محطات الأرصاد و الطاقة الشمسية بالجماهيرية لدراسة و تحليل الإشعاع الشمسي على السطح الأفقي في خمس مواقع هي طرابلس و شحات و هون و الكفرة و غات أختيرت من بين 15 محطة تغطي مناطق الجماهيرية و استنبطت معادلات تجريبية سنوية و نصف سنوية لكل منطقة يمكن إستخدام هذه المعادلا لتقدير الإشعاع الشمسي الكلي الساقط على سطح أفقي في هذه المناطق القريبة منها، كما تم درج الثوابت الخاصة بالمعادلات بجدول و نوقشت الإختلافات بين المناطق القريبة منها، كما تم درج الثوابت الخاصة بالمعادلات بجدول و نوقشت الإختلافات بين المناطق حسب الظروف الجوية، و بناء على البيانات المسجلة و المحسومة تم رسم خطوط كونتورية على خريطة الجماهيرية لبيان توزيع الإشعاع الشمسي. كما تم حساب المعدل الشهري لإشعاع الشمسي الساقط على سطح مائل وموجه نحو الجنوب، للمواقع الخمس المذكورة أعلاه و ذلك إستنادا على بيانات الإشعاع الشمسي الساقط على سطح أفقي. أستخدم نموذج لايو و جوردان(Liu & Jordan) لإيجاد المعدل الشهري لإشعاع الشمسي الكلي شهريا و سنويا و الزوايا المثلى المقابلة لأقصى طاقة يمكن تجميعها فصليا و سنويا. كذلك تم إستنباط علاقة تجريبية تمكن من تقدير الزوايا المثلى مباشرة بمعرفة خط عرض أي موقع داخل الجماهيرية. نختتم البحث بعرض الإستنتاجات و تقديم إقتراحات لمواصلة البحث في هذا المجال. Abstract The available data from meteorological and solar energy stations were used to study and analyse the solar energy radiation on horizontal surface in five locations in Jamahiriya namely: Tripoli, Shahat, Hun, Kifra, and Ghat, which were selected from 15 stations covering the whole area of Jamahiriya> Annual and semi-annual empirical relations were developed for each location; these locations or locations near by> The differences between the constants of these empirical relations are discussed. Using the recorded and calculated data, the contour lines of solar radiation are drawn on the Jamahiriya’s map. The monthly average solar radiation on south facing tilted surface has also been calculated for the above-mentioned locations, using the data available for a horizontal surface. Liu & Jordan model was used to determine the monthly and annual solar radiation. The optimum angles corresponding to maximum collected energy (annual and seasonal) were also determined. An empirical relation was also developed which can be used for estimating the optimum angle directly by knowing the latitude of any location in Jamahiriya. Conclusions and suggestions that may help for continuity of research in this area are given at the end of the thesis.
أميمة محمد محمد الفوراوي (2000)