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.
في مدينة الري القريبة من طهران الحالية ولد ابو بكر محمد بن يحيى بن زكريا الرازي سنة 251هـ/865 م وسميً بالرازي نسبة الى مدينة الري 0 أحب الرازي الغناء والضرب على العود في بداية حياته ثم هجر ذلك كله واتجه الى الطب والكيمياء 0 درس الطب في شبابه في بغداد وقد اخطأ بعض المؤرخين في ظنهم ان
يبخث البحث في عملية انهاء وتصفية الوجود المالي للشركة ودور المصفي في انهاءه واعطاء كل ذي حق حقه
The Chain's experience of reform and development monopolized with deep and exclusive concerns of the world.
Starting from the academic departments of universities and researches and study centers to the world's organizations and institutes passing through the government and the official systems in many countries that get affected , positively or negatively, now or later by china's economic development .
Searching in the china's experience of reform and development is important because it takes place in a developing country in which the leadership is succeeded in choosing the right methodology an model of changing and operating economics, making use of all the past national a
... Show Moreاهتم العديد من الباحثين والمحققين في دراسة أبي البركات الأنباري ، كونه أديبا ولغويا ومفسرا ، ونشروا معظم ما وصل إلينا من مؤلفاته ،لكن كما يبدو أن الانباري، مؤرخا ، لم ينل حظه من الاهتمام والدراسة على الرغم من أن كتابه (نزهة الألباب في طبقات الأدباء) قد نشر وحققه صفوة المحققين ([i])وذلك انهم أغفلوا التعريف بمنهجه ودراسته لاسيما وأن التأليف في كتب الطبقات من أهم مناهج الكتابة التاريخية
... Show MoreThe manuscript (Tuhfat al-Ashab wa Nuzhat al-Albab) by the author Ahmed bin Ibrahim al-Hanafi al-Srouji (d. 0ٓٔ AH / ٖٓٔٔ
AD), one of the important manuscripts because it is an encyclopedia characterized by the diversity of its topics
The Andalusi woman’s poetry forms a point upon which there has been much vagueness and prejudice may be because of the distorted versions that have recorded the women’s heritage. The
فإن مسألة التعارض بين الرواية، والفتوى، من المسائل المشهورة عند الأصوليين والفقهاء، وهي من مباحث السنة عند الأصوليين، والتي تبنى عليها مسائل متعددة، وهي من أسباب اختلاف الفقهاء، فإذا ما روى أحد الرواة حديثاً معيناً، ثم عمل بخلاف ما روى، فللعلماء في ذلك خلاف، مبني على أن العبرة بروايته
The effect of the aqueous extract of fenugreek seeds (Trigonella Foenum Graecum L.), Rhodium complex (?) with formula [RhL2CLH2O].1 1/2 ETOH and palladium (?) [pdl2].2ETOH,where L=2-hydroxy phenyl piperonalidine was studied on two cancer cell lines. The first cell line was intestine cancer of female albino mice (L20B), the second one was Rhabdomysarcomas (RD)cell line in human. The activity of the new complexes and the aqueous extract was compared to the well-known anticancer drug (cis-platin) by utilizing the in vitro system. The cell lines were treated with four concentrations of cis-platin 31.25,62.5,125 and 250 ?g/ml for 72 hour exposure time. The same concentrations were used with extract and the new complexes. This study showed that t
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