This paper presents the effect of relativistic and ponderomotive nonlinearity on cross-focusing of two intense laser beams in a collisionless and unmagnetized plasma. It should be noted here that while considering the self-focusing due to relativistic electron mass variation, the electron ponderomotive density depression in the channel may also be important. Therefore/these two nonlinearties may simultaneously affect the self-focusing process. These nonlinearities depend not only on the intensity of one laser but also on the second laser. Therefore, one laser beam affects the dynamics of the second beam and hence the process of cross-focusing takes place. The electric field amplitude of the excited electron plasma wave (EPW) has been calculated. Comparison of the theory with the recent experimental observations has also been presented.
That is feared we frequent urgent calls from Islamic scholars and leaders of the Muslim faithful to their religion and nation to a culturally، economically، politically and militarily Muslim communities، in response to the call of the divine stones in the sit-rope of God and taking the greatest causes of strength and stamina، pride and empowerment
وفي الحقيقة وأنا أكتب عن الفكر العمراني عند اليعقوبي وقفت وقفات طويلة أردت منها أن أحدد المجال الذي أبدع فيه اليعقوبي لكي أوسم موضوع بحثي، كأن أقول عنه الجغرافي أو مهندس أو رحالة أو أديب، لكني وجدته جغرافياً طبيعياً وبشرياً ومهندس بناءً عارفاً بمواد البناء وهندسة البناء وهندسة المساحة والطرق والجسور والهندسة المعمارية، لذا وجدته موسوعة لكل ما كان في عصره من العلوم، فضلاً عن كونه مؤرخاً، له مؤلفة المشهور ((
... Show Moreهدف البحث الحالي التعرف على مستوى مهارات التفكير المنظومي عند طالبات المرحلة المتوسطة في المدارس الثانوية والمتوسطة الحكومية النهارية التابعة الى مديرية تربية الكرخ االولى للعام الدراسي )2024 -2025)م، ولتحقيق هدف البحث قامت الباحثتان بإعداد مقياس مهارات التفكير المنظومي الذي يتكون من )37 )عبارة موزعة على اربع مهارات وهي) ادراك العالقات، تحليل المنظومات، تركيب المنظومات، تقويم المنظومات(، وتم تطبيقه على عينة الب
... Show MoreThe current research aims to know the relationship between bullying and parental treatment. (200) pupils were selected randomly from the fifth and sixth grades of primary schools.
Two instruments were used. The first was to measure bullying and it included 19 items. To measure parental treatment, the researchers adopted (Aletaby 2001) scale.
Statistical analysis showed that correlation between bullying , wiggle and Firm treatment style was positive Statistically significant .Bulling was correlated negatively with (neglect, careless, and Authoritarian treatment style.
abstract:
Objectives: The study aims to reveal the approach of Imam Al-Salmi in the weighting between the apparently conflicting texts, and to show the extent of his agreement and disagreement with the rest of the fundamentalists, and does he have vocabulary that can be used to elicit legal rulings in modern contemporary issues?
Method: The method of induction and analysis is one of the main tools to reach the research results. The study resorted to following the sayings of Imam Al-Salmi in various sources and fatwas and standing on them, then analyzing and applying them to the various branches of jurisprudence in the various jurisprudential chapters.
... Show MoreImam Ali Bin Al-Hussain Bin Ali (Zain Al-Abedien) (pbuh) is famous in worship, afraid from God , in spite of his origin that is related to prophet Mohammad , he felt tired of worship until he had arrived to be sick ,he sometimes felt patient and looked yellow when he would be in front of God . It is important to shed light on his worship as describing him the forth Imam of the twelfth ones .What he had said and what he had done was as a guide to whom who want to be won in this life , finally, the research concluded that faith , worship deals with interior feeling lead to worship not by increasing them or by thinking , but it is as interiorly faith.
The research aimed: 1. Definition of family climate for the university students. 2. Definition of statistical significance of differences in family climate variable depending on the sex (males - females) and specialization (Scientific - humanity). 3. Definition of academic adjustment for university students. 4. Definition of correlation between climate and academic adjustment. The research sample formed of (300) male and female students by (150) male of scientific and humanitarian specialization and (150) female of scientific and humanitarian specialization randomly selected from the research community. To achieve the objectives of the research the researcher prepared a tool to measure family climate. And adopted the measure (Azzam 2010)
... Show MoreThe shift that caused the fading art schools and the brightness of the other, which dictate the work of art based surface and defect lasting regeneration led the researcher to stop at the color of his study, as an element of fixed and mobile at the same time, hard as a lieutenant of the painting plastic and brick construction that supports a painting, The variable that follows the doctrine of the artist and the philosophy of the community, because of the extrapolation of his biography, especially in modern art and beyond is clear that compose a variety of ways and so as to ensure continuity vital to the process of drawing, color in all modes is responsible for editing shapes on the surface imaging is, without a line, shape and dimensions
... Show Moreإن قراءة شبه متأنية لبعض مواقف الاِمام السجاد( عليه السلام ) من الظالمين وأعوانهم ، وكذلك مواقفه من بعض الحركات الشيعية التي تفجّرت في زمانه ، وكيف انتقل من مرحلة التقية المؤلمة إلى مرحلة المواجهة الساخنة ، لا سيّما بعد أن استنفذ دوره التبليغي الصامت ، وارتأى أنّه لابدّ أن ينتقل من المرحلة السلبية السرية الصامتة إلى مرحلة اعلان المعارضة ، خاصة وإنّه أدرك أن خصومه عن دوره في تأليب الاُمّة ضدهم وتحشيد غضبها وإ
... Show MoreIbn al-Haytham is the pioneer of optics, which is a science that had described optics circumstances. Optics or landscape science as it was known by the Arab and Muslim scientists at the time when is a science known as the conditions of sighters in their quantity and quality as the proximity and distance from the beholder , the different forms , conditions and what mediate between the beholder and the microscopes , to explain useful knowledge of what obscures the sight of the conditions of sighters and is used to measure the space Distant criminality and mirrors.
Ibn al-Haitham wrote his famous book The Book of Mirrors and studied mistakes adopted the m
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