In the present work, the fabrication techniques of type of Nd +3-glass laser active
media : namely, Neodymium- Tellurite glass, where the glass system(TeO2(1-x) - BaOZnO-
Nd2O3x) for values of (X=1,1.5,2,2.5,3,3.5 wt%) was used.
Measurements have been taken for the signal of fluorescence spectrum of Nd+3- glass
samples. The fluorescence spectrum, for one of the samples, has been taken, after the
sequences of polishing for the out surface.
The results give signal of fluorescence spectrum for the samples. Intensity of the peak of
the signal increases with Nd +3 concentration. The fluorescence at (l=1.06 mm) for one
of the samples has been detected and the fluorescence line width was (100 cm-1). The
cross section of stimulated emission for this type of laser active media (sp(lp=1.06
mm)=3.59*10-20 cm2), and the results compared with the published data.
The searchers opinions are variant in determining the extent of impacting political risk in the host country on foreign direct investment decision. (Aharoni,1966) found, in his questionary study for group of foreign companies operating in India, that a political stability is one of the two most important factors, besides the market size, in the attraction of foreign investment, and its availability means that whether this specific country is good for foreign investment. On the other side, (Green and Benntt, 1972) are present a variant opinion to Aharonis opinion. They are reach to result state that a political instability do not impact on the general distribution of foreign i
... Show MoreThe Arab economy suffers from many structural imbalances problems which are getting complicated by the appearance of the world economic variables.
This change held risky challenges for the Arab economies in the light of unsuitable regional and international conditions. Since that it has been very essential for the Arab experts, especially those related to economy and politics, to face those new challenges or, at least, adapt with them believing that they can have both positive and negative impacts on the Arab economy.
This study has acquired its importance in the light of the critical levels the Arab economy reached out of the world economic variables, resulting in long-term
... Show Moreملخـــص البحــــث
كان للإمام النسفي دور كبير في دراسة منهج المعتزلة ، والرد عليهم وذلك في مؤلفاته المتنوعة ، وفي طليعتها تفسيره المشهور : مدارك التنزيل وحقائق التأويل ، ومن يطلع على هذا الكتاب يجده بلا شك كتاباً مهماً ، زاخراً بأنواعه العلوم والفنون ، ومنها ردوده على المعتزلة في كثير من المسائل الكلامية التي خالفوا فيها أهل السنة والجماعة . وجاءت خطة البحث في مبحثين رئيسين بعد المقدمة :<
... Show MoreBackground: The irradiation of teeth with a laser results in an interaction between the light and the biological constituents of the dental hard substance, which is converted directly into heat.This thermal effect is the cause of the structural and chemical enamel changes.The combined treatment of topical fluoride agent with laser may increase fluoride uptake, and reduce progression of caries-like lesions. The aim of this study was to measure the uptake of the acidulated phosphate fluoride and sodium fluoride to the buccal and lingual caries-like lesion enamel surfaces before and after irradiated by Nd-YAG laser in comparison with matching control group. Materials and methods: The sample consisted of 30 human healthy upper premolar teeth wh
... Show Moreالمقدمة وأهمية البحث : يشهد العالم تقدما في كافة مجالات الحياة المختلفة وتزداد الحياة صعوبة يوما بعد يوم ، ويزداد البحث في كافة المجالات التي تعمل على خدمة الإنسان ولقد طال هذا التقدم النشاط الرياضي ،فقد يكون لتطور التدريب الرياضي وتنوع أساليبه الدور الكبير في تحقيق اللياقة البدنية التي تعد إحدى أهم الأهداف التي يرمي إليها الدرس في كلية التربية الرياضية . واللياقة البدنية تستمد أهميتها من كونها إحدى مكونات ا
... Show MoreThe effect of laser radiation on human aorta, coronary, and pulmonary arteries, and pulmonary veins has been investigated. Xenon-Chloride (eximer), Nitrogen, and Nd-YAG pulsed lasers of wavelengths 308, 337, and 1060 nm respectively were used. Their effects on fresh postmortem tissues, normal and diseased, was studied. The diameter and depth of ablation of the exposed tissues, in air, were measured as a function of many factors related to the type of laser and nature of the tissue. The effect of properties of the applied lasers, such as average power density and deposited energy density, on the exposed tissue surface were studied. The increase of these two parameters cause an increase in the depth and diameter of ablation. However the di
... Show Moreيهدف هذا البحث الى بيان مفهوم محاسبة التحوط والمعاملات بالعملة الاجنبية والمشاكل الناجمة عن التعامل بها وتسليط الضوء على القواعد المحاسبية المحلية والدولية المتعلقة بمحاسبة التحوط للحد من مخاطر التقلبات في اسعار صرف العملة التي تتعرض لها الوحدات من خلال جعل الابلاغ المالي للوحدات المحلية بالتوافق مع المعايير الدولية للإبلاغ المالي ولإنجاز هذا الهدف تم اختيار عينة من الوحدات الاقتصادية الع
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