The nonlinear refractive index and the nonlinear absorption coefficient of unmodified and functional poly(methyl methacrylate) PMMA films were studied before and after the addition of the filler by the z-scan technique, using a Q-switched Nd:YAG laser at two wavelengths: 532 nm and 1064 nm, and at three input energies (13, 33 and 53) mJ. Both linear and nonlinear refractive indices and absorption coefficients of polymer films were studied by using UV-VIS spectrophotometer. The results show that the creation of functional PMMA from unmodified PMMA will increase the nonlinear optical properties in the functional PMMA/copper matrix more than in the unmodified PMMA/copper matrix. Hence, the functional PMMA appears promising as a useful third-order nonlinear material. The nonlinear refractive index is directly proportional to the input intensity and directly proportional to the increase in the concentration of the filler, while the nonlinear absorption coefficient is inversely proportional to the input energy and inversely proportional to the increase in the concentration of the filler. The nonlinear effect is more enhanced at the 532 nm wavelength than at 1064 nm..
Varied uses of international rivers in the past few decades dramatically, resulting in this multiplicity of uses and all associated with it for the occurrence of freshwater scarcity activities, and thus an increase in conflicts and disputes around on the rights of each of the riparian countries to benefit from the waters of the river at various purposes, particularly the establishment of dams on some of them as is the case (Renaissance Ethiopian) big impact on downstream countries Dam (Egypt and Sudan), due to the Oukuahma at the end of the Nile Valley made them vulnerable to environmental fluctuations, political crises facing the Nile basin countries, and any reduction in the proportion of water is not only the Nile River, but for all r
... Show MoreWhen exercising their authority in the jurisprudence, judges are subject to a set of restrictions that they must adhere to, as they do not want their jurisprudence to be accepted and welcomed by law practitioners in general, and legal scholars in particular, and in contrast to it, the arrows of criticism and defamation will extend to that jurisprudence, and then they will have to reverse them . Perhaps the most important of those restrictions imposed on judges is their observance of justice between the parties to the lawsuit through their lack of bias for one of the parties at the expense of the other, in addition to their observance of public order and public morals, as well as their observance of the legal texts that they work under its u
... Show Moreالملخص - يهدف البحث الحالي الى تعرف اتجاهات مدرسي ومدرسات المدارس الثانوية نحو التربية الجنسية والتعرف على اثر متغير الجنس (ذكور، إناث) في تكوين اتجاهات تدريس التربية الجنسية في التعليم - الثانوي فضلاً عن تعرف التطبيقات التربوية للتربية الجنسية في المدارس الثانوية ، إذ ان التربية الجنسية واحدة من أهم فروع التربية في الإسلام , وهي ذات أهمية في نشر الوعي الديني والصحي والتربوي والاجتماعي والثقافي في المجتمع
... Show MoreThe research aims to:
- Show the effect of corporate governance on the quality performance of certified public accountants through establish the concept and principles of corporate governance and the concepts, importance, standards of quality auditing.
- Forming a proposed framework for quality performance of certified public accountants under the corporate governance, which show the concepts objectives, principles, standards, and constraints of the proposed framework.
The research in one aspect of it based on the study of theoretical background which re which relate to the subject beside the global experiments and opinions of the specialists
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This study came to discuss the subject of industries dependent on petrochemical industries in Iraq (plastic as a model) during the period 2005–2020, and the study concluded that the plastic industries contribute to areas of advancement and progress and opportunities to deal efficiently with the challenges posed by the new variables, the most important of which is the information revolution. communications and trade liberalization, and this is what contributes to the competitiveness of these industries. And because the petrochemical industry in Iraq has an active role in establishing plastic industrial clusters and clusters of micro, small, and medium industries by providing the necessary feedstock for these industries in various fields
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One of the bases of civilization is architecture; the philosophy of applying architecture on the ground is considered the base of it's growth
The study aimed at the following:
Identify the differences in average scores core thinking skills kindergarten children by variable sex (male - female), and by variable age (5.6 - 5.11).
To achieve this researcher adopted a standardized test of core thinking skills for the kindergarten children, which was built and standardization by the researcher Meyada Asaad Mussa 2012 . applied test on a sample of (814) ) boys and girls who were randomly chosen form, from directorates of Baghdad Education Adoption of the proportional distribution.
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يعد موضوع الثورات العربية من الموضوعات التي تحظى بأهمية كبيرة على المستويين الاقليمي والدولي، لذا فقد طورت مؤسسات الابحاث الدولية ومراكز صنع القرار السياسي والاستراتيجي الاطر والمفاهيم الجديدة في مجال السياسة الدولية، نظرا للتطورات التي شهدتها المنطقة العربية والتي استدعت التطرق الى مجموعة من المفاهيم النظرية ذات العلاقة الوثيقة بما هو حاصل في المنطقة العربية من تغييرات مما تطلب الامر البحث والتدقيق ومن
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