In this work the strain energy of tetrahedrane and its nitrogen substituted molecules were calculated by isodesmic reaction method according to DFT quantum chemical fashion, the used basis set was 6-31G/B3-LYP, in addition all structures were optimized by RM1 semi-empirical method. From the obtained data we estimate an empirical equation connect between strain energy of the molecule with charge functions represented by dipole moment of the molecule plus accumulated charge density involved within the tetrahedron frame plus the number of nitrogen atoms. The results indicate the charge spreading factors by polarization and processes are the most important factors in decreasing the strain energy.
This paper develops the work of Mary Florence et.al. on centralizer of semiprime semirings and presents reverse centralizer of semirings with several propositions and lemmas. Also introduces the notion of dependent element and free actions on semirings with some results of free action of centralizer and reverse centralizer on semiprime semirings and some another mappings.
مستخلص البحث كان الهدف من البحث هو معرفة نسب نجاح وفشل بعض المهارات الهجومية المركبة من ثلاث مهارات بكرة السلة للشباب.، إذ لوحظ بأنه لا تكتمل عملية التقدم من خلال إتقان المهارات الأساسية الهجومية المفردة فقط وإنما في القدرة على الدقة والثبات في أداء الربط فيما بينها (التركيب)، وعكس ما تقدم يعد واحد من الأسباب التي تسبب ضعفاً في المستوى ومما يزيد من الأخطاء في الأداء تبعاً لذلك. وفي ضوء ما تقدم تم تصوير ست مباري
... Show MoreThe research aims to show the relationship between the use of automated accounting systems technology and its impact on enhancing the efficiency and effectiveness of the internal control system in a sample of Bahraini universities in light of the rapid changes in the electronic business environment. Automated accounting and its impact on enhancing the efficiency and effectiveness of the internal control system, and it is concluded through the analytical study of the research sample that there is a percenta
... Show Moreاشتمل هذا البحث على مقدمة البحث واهميته والاثر المهم للوسائل التدريبية اذ تجلت أهمية البحث في الوسائل المساعدة ودورها في تطوير أداء السلسلة الحركية على عارضة التوازن للطالبات مما يساعد في اختزال الوقت وتقليل الجهد المبذول وبناء قاعدة جيدة للمرحلة المقبلة وكذلك إيجاد انسب التمرينات وفق للوسيلة المساعدة المستخدمة وذلك لغرض تطوير المهارات الأساسية على عارضة التوازن في جمناستك الفني وحددت الباحثة مشكلة
... Show MoreThe game of basketball (orange ball) is considered one of the fast and exciting games in the world. It is played by both sexes and different ages. It has Olympic and international championships and has various performance skills, including defensive ones. This game requires physical abilities that players must have for duties during matches, including special endurance that is compatible with... The peculiarity of the game is the changing rhythm and positions on the field. The importance of the research lies in the importance of special exercises to develop special endurance and its role in influencing the defensive skill performance of the players throughout the duration of the match.The problem of the research appeared in the decline in i
... Show MoreThe exchange rate is of great importance at the global and local levels alike, as this importance increases with the increasing rates of development of economic relations between countries of the world due to openness and integration into the global economy, expressed by the expansion of the volume of trade and financial relations between countries. The Central Bank of Iraq has set the need to stabilize this price as a goal to reduce inflation rates and reduce them to the internationally accepted rates by using the foreign currency sale window to achieve a balance between the forces of supply and demand for foreign currency and to preserve the value of the Iraqi dinar. The research concluded that the central bank was It has a maj
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