A random laser is a non-conventional laser whose feedback mechanism is based on dissorder-induced light. However, random lasers occur in gain media with numerous scatterers and produce coherent laser emission without any predesigned cavity. The generation of coherent emission from multiple scattering is quite general and its basic principles are shown here using sulforhodamine B-TiO suspensions system. These suspensions were pumped with 337.1 nm pulses from N2 laser and the spectral and temporal behavior of light emitted from the pumped surface was recorded. When we pump power above a certain threshold a dramatic narrowing of the emission line width and a shortening of the emitted pulses were observed. We have experimentally found that in a random laser based scattering, the threshold pumping density decreases with pump energy increased.
Stress is an inevitable part of life. Stress occurs when stressful events of self, environmental, or social origin affect the individual's resilience and threaten to collapse his psychological and physical systems. The stress represents difficulties and obstacles that may exceed the individual's ability to bear them and deal with them, which causes him stress and causes negative effects on his psychological and physical health. Therefore, the current research aimed to identify the negative effects of psychological stress on the psychological and physical health of the individual through the literature that dealt with this topic. It was among the results of the research that one of the negative effects of stresses on mental health is the
... Show MoreAgriculture is one of the important job in the human life. Since the first beginning of humanity life, agriculture was the basis property in order to get individual foods. The Holy Quran and Hadith were supplied agriculture and all Muslims were followed this field especially after Islamic state expansion and its possessive many lands which developed directly our Islamic civilization.
Spiritual training is aimed to plant the faith in individuals soul because it is the basis of the religion, but rather a strong deferent that accompanies human life in his thinking and management and awakens
إن تاريخ التعليم في السنوات الأخيرة هو قصة تحكي تطور التعليم من بُعد والتعليم المفتوح وباختصار " الإنفتاح التعليمي " Opening up education؛فعلى مدى عقود قليلة عملت التكنولوجيا الحديثة مثل الكمبيوتر الشخصي ، والوسائط المتعددة التفاعلية ، والإنترنت باستمرار على توسيع فرص
The codification of the social history of the city of Baghdad will be filled with an inherited folklore and folklore that has been descended to it from the previous generations with all its tales of folk tales, metaphors, parables, crafts and industries. Immortal
يُعدّ التناص أحد تقانات البلاغة الحديثة – الأسلوبية- التي تنهض برقي النص ، بوصفه عنصراً فاعلاً في بلورة المعنى وتناغمه مع قصدية المتكلّم ؛ ممّا يسهم في تواشج علائقية البنية الدلالية للنص وتعاضدها النسقي في تكوينه ؛ لفتح نافذة التأويل عند المتلقي بحثاً عن الدلالات المتغلغلة في البنية العميقة ، وهذا ما بدا واضحاً في متن كتاب (غرر البلاغة) للصابي ، فهو يزخر بنصوص تناصية دينية وأدبية ، تمدّ المعنى بطاقات جمالية م
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Международные контакты обусловили интерес к изучению основной формы общения – диалога. Форма диалога в каждом из контактирующих в процессе общения языков должна быть рассмотрена в разных аспектах – не только лингвистическом, но и социолингвистическом и этическом. Это объясняется тем, что в речевой коммуникации необходима как адекватность выражения мысли, так и соблюдение тради
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