This work characterizes the fractographic features of the neat epoxy and ZrO2 epoxy nanocomposites. All samples were subjected to a tensile test to determine the tensile strength and tensile modulus. SEM images were used to study the morphology of the fractured surface. The fractographic of the fracture surfaces were studied by microstructure analysis program (j-images) to specify the effect of ZrO2 nanoparticles on tensile performance and failure mechanism for ZrO2 epoxy nanocomposites. The tensile test results show that the addition of ZrO2 nanoparticles (2, 4, 6, 8, and 10 vol.%) to the epoxy matrix leads to increase the tensile strength about 40% for optimal content of ZrO2 nanoparticles at 4 vol.%, tensile modules of ZrO2 epoxy nanocomposites increased about 200% for optimal content of ZrO2 nanoparticles at 4 vol.%. SEM images show that the patterns of fractured surfaces of ZrO2 epoxy nanocomposites are different from the pattern of the neat epoxy. The fracture roughness of ZrO2 epoxy nanocomposites increased with the increases of the percentages of ZrO2 nanoparticles, where the increment of fracture roughness about 30% for optimal content of ZrO2 nanoparticles at 4 vol.% can be indicator for the improvement of mechanical properties (tensile strength and modules).
The development of a reversed phase high performance liquid chromatography fluorescence method for the determination of the mycotoxins fumonisin B1 and fumonisin B2 by using silica-based monolithic column is described. The samples were first extracted using acetonitrile:water (50:50, v/v) and purified by using a C18 solid phase extraction-based clean-up column. Then, pre-column derivatization for the analyte using ortho-phthaldialdehyde in the presence of 2-mercaptoethanol was carried out. The developed method involved optimization of mobile phase composition using methanol and phosphate buffer, injection volume, temperature and flow rate. The liquid chromatographic separation was performed using a reversed phase Chromolith® RP-18e column
... Show Moreيهدف هذا البحث الى تحديد اثر الاختلاف في ادراكات العاملين للعدالة التنظيمية في المنظمات قيد البحث. وقد تم اعتماد الادراك كمتغير تفسيري، اما العدالة التنظيمية فمثلت المتغير الاستجابي بانواعها الثلاث (العدالة التوزيعية، العدالة الاجرائية، والعدالة التفاعلية)، ولتحقيق اهداف البحث فقد تم اختيار دائرة صحة بغداد/ الكرخ مجتمع للدراسة. وجرى تصميم استبانة ووفق مقياس خماسيي الدراجات وجرى تحليل البيانات باستخ
... Show MoreTransportation problems are considered as a type of operation research problems. In fact, they deal with scheduling transportation of goods from their source to delivery sites in the minimum cost.
Such problems can be solved by the available traditional methods, which include; North-West corner, Least cost and Vogel’s method. As well as if this transportation problem is considered as a linear program it can also be solved by using Simplex method
The goal of the present study is to compare different research methods to provide the optimal and minimum cost.
This study was applied to resolve a transportation problem related to land Transportation Company, w
... Show Moreليست الادارة المحلية أو نظام الحكم المحلي ابتكاراُ حديثاً للانسان، بل أنه لازم البشرية منذ أقدم العصور وحتى الآن، إذ الملاجظ أن القرى الصغيرة نشأت قبل أن تنشئ الدولة أو قيل أن يتبلور مفهوم الدولة في الوقت الحاضر وكانت القرى والمدن تجتمع بين حين وأخر- اجتماع أفرادها- لادارة شؤونهم وحل مشاكلهم، وكان هذا خير دليل لتطبيق مفهوم الديمقراطية المباشرة بين أفراد المجتمع الواحد، ولذلك فإن الحك
... Show Moreاِنطلقت فِكرة إعداد هذه الدِّراسة بعد الاِطِّلاع على محاضر مجلس الأُمَّة التركي الكبير، ومعرِفة التشريعات التي تناولت مفاصل الحياة الاِجتماعيَّة في تُـركيا، وبيَّنت هذه التشريعات التي نظَّمت مُستوى العلاقة بين المواطن والدولة، وأسهمت في وضع حلول مُـشكِلاتٍ اِجتماعيَّة عديدة منها؛ ما له صِلة بإجراءات الدولة في رفع المظلوميَّة عن المواطنين الأتراك والمقيمون فيها، مع تشخص بعض الظواهر الاِجتماعيَّة السِّـ
... Show MoreThis work is devoted to a comparative study of the phenomenon of enantiosemy in Russian and Arabic.Everyone knows the term antonyms - words of the same part of speech, opposite in meaning, such as: Day and night, white and black, truth and lies. But in Russian, Arabic and other languages there is an interesting phenomenon, which consists in the fact that one word has two opposite meanings. Such a phenomenon in linguistics is called enantiosemy (from the Greek words enantios - "opposite" and sema - "sign")
Eight different Dichloro(bis{2-[1-(4-R-phenyl)-1H-1,2,3-triazol-4-yl-κN3]pyridine-κN})iron(II) compounds, 2–9, have been synthesised and characterised, where group R=CH3 (L2), OCH3 (L3), COOH (L4), F (L5), Cl (L6), CN (L7), H (L8) and CF3 (L9). The single crystal X-ray structure was determined for the L3 which was complemented with Density Functional Theory calculations for all complexes. The structure exhibits a distorted octahedral geometry, with the two triazole ligands coordinated to the iron centre positioned in the equatorial plane and the two chloro atoms in the axial positions. The values of the FeII/III redox couple, observed at ca. −0.3 V versus Fc/ Fc+ for complexes 2–9, varied over a very small potential range of 0.05 V.
... Show MoreResumen:
El horóscopo que es una predicción deducida de la posición de los astros del sistema solar y de los signos de Zodiaco, intenta no sólo predecir el futuro, sino también influir en el comportamiento del lector, orientándolo para que actúe adecuadamente y la invitación a actuar ante ese futuro que se aconseja mediante imperativos, perífrasis y otros recursos lingüísticos. Los horóscopos se caracterizan por su gran popularidad que existen en periódico o revista en columnas enteras dedicadas al tema, en donde se detallan la influencia que tendrá el día o el mes de cada uno de los signos correspondientes al zodíaco, siempre teniendo en cuenta la posici
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