Hollow core photonic bandgap fibers provide a new geometry for the realization and enhancement of many nonlinear optical effects. Such fibers offer novel guidance and dispersion properties that provide an advantage over conventional fibers for various applications. Dispersion, which expresses the variation with wavelength of the guided-mode group velocity, is one of the most important properties of optical fibers. Photonic crystal fibers (PCFs) offer much larger flexibility than conventional fibers with respect to tailoring of the dispersion curve. This is partly due to the large refractive-index contrast available in the silica/air microstructures, and partly due to the possibility of making complex refractive-index structure over the fibe

هدفت الدراسة إلى استخدام مقاييس الدافعية العقلية وعلاقتها باكتساب بعض مفاهيم السلامة المرورية لتلاميذ الصف الخامس الابتدائي , واستخدمت الباحثتان المنهج الوصفي بأسلوبي المسح والعلاقات الارتباطية لملاءمته لطبيعة البحث , إذ تكونت عينة الدراسة من (75) تلميذ وتلميذه من تلاميذ مدرسة فدك الابتدائية الأهلية , إذ قامت الباحثتان بأستخدام مقياس الدافعية العقلية والمكون من (25) فقرة  وأختبار تنمية بعض مفاهيم السلام

An essential element in English as a foreign language (EFL) learning is vocabulary. There is a big emphasis on learning the new words' meaning from the books or inside classrooms. Also, it is a major part of language teaching as well as being fundamental to the learner but there is a big challenge in vocabulary instruction due to the weak confidence by teachers in selecting the suitable practice in teaching vocabulary or they sometimes unable to specify a suitable time for it during the teaching process. The major aim of this study is to investigate the value of posters in vocabulary learning on the 2nd grade students at Halemat Alsaadia High School in Baghdad – Iraq. It hypothesized that there are no statistically significant differences

A cost-effective and efficient detector was created to conduct thorough turbidimetric measurements by reaction of Co (II) ion with calcium ferro cyanide to form bright green particulate, using the method of continuous flow injection analysis, the use of NAG-5SX1-1D-SSP Analyzer in determining cobalt (II) ion in a test for the validity of the new design. The NAG-5SX1-1D-SSP Analyzer is composed of five irradiation sources of white snow leds having the diameter of 10 mm with one solar cell of 55 mm length, 13.5 mm width. Using a selector switch to select the optimum voltage to be used which was 2.7 VDC. Under conditions of optimization, cobalt (II) ion was determined at 0.005–20 mmol. L–1(n = 23) while linearity dynamic range 0.005–7 mm

توطئة

ظهر اهتمام متزايد في إدارة سلسلة التجهيز (Supply Chain Management) خلال الأعوام العشرين الماضية، بوصفها مصدراً ثرياً للتنافسية (Competitiveness) وخلق القيمة (Value Creation). ولقد جاء هذا التطور بفعل موجتين من التطور: الأولى، تمثلت بزيادة التوجه نحو التوريد الخارجي الستراتيجي (Strategic Outsourcing) كرؤية للشركات بأن تصبح سريعة جداً بالتركيز على

 Urban agriculture is one of the important urban uses of land in cities since the inception of cities and civilizations, but the great expansion of cities in the world during the twentieth century and the beginning of the twentieth century and the increase in the number of urban residents compared to the rural population has led to a decline in this use in favor of other uses.

 This decline in agricultural and green land areas in cities has negatively affected the environment, natural life and biological diversity in cities in addition to the great impact on the climate and the increase in temperatures and the negative impact on the economic side, since urban agriculture is an important pillar of the economy, especially

أن الغرض من هذه الدراسة هو التحليل الهيكلي لبنية مقياس الصحة النفسية لطلبة الجامعة الذي طورته الجنابي (1991) باستخدام التحليل العاملي. إن 66 طالبا و95 طالبة من كلية التربية في الجامعة المستنصرية قد استجابوا لفقرات المقياس. وقد أظهر التحليل العاملي وجود خمسة عوامل فسرت 30% من التباين, وان هذه العوامل هي الإستقرار العائلي، والأمن الاقتصادي، والمسؤولية الإجتماعية، وتقدير الذات، والأمن النفسي.

The γ- mixing ratios of γ- transitions from levels of 56Fe populated in reaction are calculated using least square fitting program for the first time in the case of pure and mixed transitions the results obtained have been compound with γ Values determined by other methods .The comparison shows that the agreement is good this confirmed the valilety of this method in calculating of values for such γ- transitions key word: γ- transition ,Multipole mixing ratios ,Least square fitting method.

African-American writers during the 19th century wrote in the shadow of the prominent romance, sentimental, and domestic fiction. Harriet Wilson’s Our Nig (1859) reflects an “alternative social character”, for the female protagonist suffers racism in the free North, because she is a mulatto child. Through depicting the life of free blacks, who supposedly lives a better life than Southern slaves, Wilson exposes how she has actually lived and sensed life in antebellum America. According to Raymond Williams (2011), there are two kinds of literary writings. The first represents the general tendency of the age, and he calls it “dominant social character”; representing the majority content of both the public writing and speaking. But, a