No abstract

‫البحث‬ ‫ملخص‬ ‫ال‬ ‫هذا‬ ‫في‬ ‫عمى‬ ‫يعتمد‬ ‫عددية‬ ‫امثمية‬ ‫نموذج‬ ‫صياغة‬ ‫تم‬ ‫بحث‬ ‫يبية‬ ‫التجر‬ ‫القيم‬ ‫ل‬ ‫من‬ ‫كل‬ ‫الضغط‬ ‫يبي‬ ‫التجر‬ (0-120) kbar ‫و‬ ‫تداد‬ ‫االر‬ ‫من‬ ‫الخالي‬ ‫الجزء‬ r fexp =f p /f 0 ‫لتوضيح‬ ‫وذلك‬ ‫تأثير‬ ‫الثاني‬ ‫و‬ ‫األول‬ ‫كرونيشن‬ ‫ومعامل‬ ‫ديباي‬ ‫ة‬ ‫ار‬ ‫حر‬ ‫درجة‬ ‫من‬ ‫كل‬ ‫عمى‬ ‫الضغط‬ (, q) ‫اذ‬ ‫أمكن‬ ‫استنتاج‬ ‫ا‬ ‫المثمى‬ ‫لقيمة‬ ‫م‬ q ‫القيمة‬ ‫وباستخدام‬ ‫لمنحاس‬ ‫المثمى‬ ‫الغرفة‬ ‫ة‬ ‫ار‬ ‫حر‬ ‫درجة‬ ‫عند‬ ‫دبياي‬ ‫يب‬ ‫تقر‬ ‫مع‬ ‫الضغط‬ ‫تاثير‬ ‫وتحت‬ ‫تداد‬ ‫االر‬ ‫من‬ ‫الخالي‬ ‫الجزء‬ ‫حساب‬ ‫تم‬ r ftheor =f p /f o ‫ألشعة‬ ‫المنبعثة‬ ‫كاما‬ ‫من‬ Fe 57 ‫في‬ Cu ( Fe 57 : Cu ) ‫العممية‬ ‫القيم‬ ‫مع‬ ‫متطابقة‬ ‫النتائج‬ ‫وكانت‬ ‫المأخوذة‬ ‫مصادر‬ ‫من‬ ‫أخ‬ ‫رى‬ . ABSTRACTIn the present work a numerical optimization model is constructed which is based on the experimental pressure (p exp ) and experimental recoilless fraction ratio (r fexp =f p /f 0 ) data in order to explain the pressure effect on Gruneisen parameters(, q) and Debye temperature.The model was able to compute the optimum q value for copper, the observed optimum value for q was used with Debye approximation at room temperature under pressure to calculate the recoilless fraction ratio r ftheor =f p /f o for (Fe 57 -Cu), It has been found that the calculated results of (ffraction) are in good agreement with the experimental data of recoilless fraction ratio.

The elastic properties such as (compressibility range from (1 to 0.6 values), isothermal bulk modulus and pressure derivative of isothermal bulk modulus) have been computed using (vinet, Birch-Murghun, Shanker, poireior)EOSs, the results were compared with the experimental data. The effect of high temperature and pressure on the four thermodynamic properties for copper have been studied. The vibration energy of atoms (E D) in a solid copper (Cu) and heat capacity at a constant volume (C V) have been evaluated using Debye model and the effect of pressure on Debye temperature. Finally , melting curve representing the variation of melting (Tm) with pressure have been Calculated for copper by using Mie Gruneison-Debye equation (based on the above equation of states), Lindemann and Kumer equations, also the melting gradient was computed. It is found that melting temperature increases with pressure in a non-linear manner such that the melting gradient decreases gradually with increase in pressure. The results were found in good fitting with experimental data.

Equations of state are used for the evaluation of pressure effects on solid (Alkali halides) at room temperature and high temperature up to melting point, Thermodynamic properties such as V o , of alkali halide (NaCl-B1) at high pressure and room temperature have been evaluated and the results are compared with experimental data and gave good results up to 5 GPa but beyond it the results of these equations of state diverge from experimental data while Bardeen equation of state gave good agreement with experimental data , the effect of high pressure and high temperature on vibration energy of atoms ()and on heat capacity at constant volume () of (NaCl-B1) are calculated by using Debye Model and gave good agreement with the theory, also thermal volume and pressure (ℎ),(ℎ) and thermal expansion coefficient () are calculated by using thermal equation of state by Kumar. Finally, melting curve of (NaCl-B1) was calculated by using Kumar thermal equation of state with Lindeman equation the results were compared with experimental data. Also inter ionic distance at melting () for (NaCl-B1) was calculated by two ways, first by using lattce potential energy and second by using Anderson equation, and compared with data of other researcher and a good fitting was observed.